Автор: Johnsen M.A.  

Теги: physics   chemistry   reference book   aerosols   aerosol industry  

ISBN: 0960-3250-3-4

Год: 1982

Текст
                    THE AEROSOL
HANDBOOK
2
nd EDITION
MONTFORT A. JOHNSEN
DANVILLE, ILLINOIS
WAYNE DORLAND COMPANY
Publisher: Eleonore K. Dorland
Editor: Gabrielle J. Dorland
MENDHAM, NEW JERSEY


IV The Aerosol Handbook Copyright 1982 by Wayne Dorland Company. All rights reserved. Printed in the United States of America. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. 82: Library of Congress Catalog Card Number 72712 ISBN 0960 3250 3-4 Typesetting: Benway, Maxwell & Smith, Inc., Chatham, N.J. Printing: Compton Press, Inc., Morristown, N.J.
V This second edition of THE AEROSOL HANDBOOK is dedicated to WAYNEE. DORLAND. . . Always a strong supporter of the aerosol industry, he gave it more status and identity when he began the publication of AEROSOL AGE in May, 1956 — a magazine devoted to aerosols: their technology, production and marketing. Wayne is also recognized as an organizer and charter member of the Aerosol Golf Invitational, as well as for many other contributions to the industry. It was his inspiration in 1970, followed by many hours of work, that led to his publication of the First Edition of THE AEROSOL HANDBOOK in 1972. In 1980 he again inspired the author, Montfort A. Johnsen, that a committment of time and effort be made to produce a Second Edition of the book. The work was started and Wayne devoted much of the last year of his life to compiling and organizing data for the book. His health failed and he died May 11, 1981. His work was continued and has now been completed by his wife, daughter and close friend. Wayne's last fond wish for the industry he loved has now been brought to reality. EKD. GJ.D. \ M.A.J.
VI The Aerosol Handbook Sponsors Aeropres Corporation Continental Can Company, U.S.A. Crown Cork & Seal Company, Inc. Diversified Chemicals & Prapeliants Company E.I. du Pont de Nemours & Co. (Inc.) Industrial Hydrocarbons, Inc. Peterson/Puritan, Inc. Precision Valve Corporation Summit Packaging Systems Inc.
X The Aerosol Handbook List of Tables TABLE PAGE 1. U.S.A. Production of Consumer Retail Packages 6 2. U.S.A. Production of Toiletries Retail Packages 6 3. Aerosol Shaving Cream — Summary of Customer Complaints 12 4. Unit Market Shares of the Aerosol Hair Spray 16 5. Unit Hair Spray Market in England; 1972-1980 16 6. Unit Hair Spray Market injapan; 1972-1980 16 7. TotalUnit Hair Spray Market in the U.S. A 17 8. U.S.A. Hair Spray Market Profile; 1980 17 9. Unit Shares of Major Hair Spray Brands in the U.S.A. ..18 10. Hair Spray Formulations Using Dimethyl Ether 19 11. Unit Market Shares of Antiperspirants and Deodorants ..21 12. LevelofAntiperspirant Salt in Various Product Forms ..22 13. Antiperspirant/Deodorant Market in England 22 14. Antiperspirant/Deodorant Aerosol Market in Japan ....23 15. Dollar Volume Brand Share of Major Antiperspirant/ Deodorant Aerosol Products; 1977-1978 24 16. Unit Volume of Aerosol Perfumes and Colognes in the U.S.A. andjapan; 1970-1979 25 MARKETING TABLE PAGE 17. Market Performance of Sun Care Products 26 18. Unit Sales of Aerosol Insecticides; 1970-1980 27 19. Aerosol Product Sales; 1979-1980 27 20. Unit Sales of Aerosol Paints; 1974-1980 30 21. Unit Sales of Air Fresheners; 1970-1980 30 22. Unit Sales of Food Aerosols Including Whipped Cream Products; 1972-1980 (U.S.A.) 33 23. Worldwide Consumption of Aerosols; 1979 35 24. Production and Uses of Chlorofluorocarbons P-ll and P-12; 1958-1980 35 25. Propellent Selection for Aerosols Filled in 1979 (%) 36 26. Aerosol Productions During 1979 36 27. Market Share of Selected Aerosol Products 37 28. Aerosol Production of Larger Volume Countries 38 29. World Production of Aerosols; 1970-1980 39 30. Ten Year Variations in U.S.A. Aerosol Categories 40 31. Advantages of the Aerosol Dispensing System 45 32. Disadvantages of the Aerosol Dispensing System 46 1. Market Share of Aerosol Containers 48 2. Major Aerosol Can Suppliers in the U.S. A 48 3. Factors Influencing the Structural Strength of Aerosol Cans 51 4. Thickness of Tinplate Used in Aerosol Cans 51 5. Variation of Tinplate Thickness 51 6. Variation of Baseweight Thickness at Different Locations 52 7. D.O.T. Requirements for Metal Aerosol Containers .... 52 METAL CONTAINERS 8. Buckle Resistance of Typical 211-Diameter Can Bottoms 53 9. Temper Specifications for Steel Plate 54 10. Dome Labeling Recommendations for Three-Piece Aerosol Containers 57 11. Standard Sizes for Three-Piece Aerosols 59 12. Preferred Can Sizes and Volume Fills in Europe Federation of European Aerosol Associations; 1979 62 13. Body Plate Preferences for Various Can Diameters 63
List of Tables XI TABLE PAGE 14. Accuracy of Electrochemical Prediction of Test Pack Results 67 15. Solder Codes for Aerosol Containers 70 16. Modifications of the Process for Welding Cans 71 17. U.S.A. Tinplate and CCI-Steel Aerosol Can Sizes 73 18. Aluminum Aerosol Can Suppliers to the U.S. A 75 19. Aluminum Aerosol Container Profiles -1982 76 20. Aluminum Aerosol Cans Available in the U.S. A 78-79 21. Alusuisse Straight-Shouldered Aluminum Cans 80-81 22. Total Height of Monobloc Aluminum Aerosol Cans 81 1. Relative Propellent Energy, as a Guide to Bottle Selection 119 2. Ignition Consequences Upon Instant Release of C-17 (N-Butane) From a Ruptured Plain Glass Aerosol 121 3. Various Aerosol Colognes, Based on Use of Dimethylether 122 TABLE PAGE 23. EEC Directive (Annex III) Giving the Range of Volumes for Products Sold in Aerosol Form 82 24. Approximate Compositions of Aluminum Alloys Used in Aerosol Can Manufacturing 86 25. Label Dimensions and Print Areas for Aluminum Cans Made by Metal Box Limited 90 26. Specifications for Paper Labels Used for Steel and TinplateCans 94 27. Pressure of Various Aerosols at Elevated Temperatures . . 97 28. Critical Pressure Ranges for Tinplate and Aluminum Aerosol Containers 98 GLASS AEROSOLS 4. Wheaton "SAF" Process Uncoated Aerosols and Plastic Coated Aerosols 123 5. Drop Testing Results for Various Uncoated Glass Aerosols 126 6. Parameters Involved in Drop Testing Glass Aerosols ... 128 PLASTIC AEROSOLS 1. Permeation Rates Through 4-oz. Zytel 101 Bottles of 0.050"Average Wall Thickness 146 2. Permeation Factors at Different Temperatures 146 1. Properties and Recommendations for D&A Cup Latexes 155 2. Weight Loss Data for a Non-Flammable Aerosol Insecticide Product 159 3. Typical Gasket Swell Levels After Immersion in Common Aerosol Solvents 160 4. Comparisons of Weight Loss Between High Methylene Chloride and High 1,1,1-Trichloroethane Aerosol Insecticides 161 3. Computer Cost Analysis for 2-oz. Celcon Bottle 147 4. Plastic Identification Table 148 VALVES 5. Nomenclature and Structure of Elastomers Used for Valve Gaskets 162 6. Dip Tube Swelling When in Contact with Solvents 168 7. Compilation of Seaquist Valve Company Valve Series and Basic Assemblies 172 8. CSMA "A-D Dimension" Chart for Suggested Dip Tube Lengths 182 COVER CAPS 1. Aerosol Plastic Cover Cap Identification Chart .... 187-189 2. Variation of Cap Wall Thickness with Diameter 190 3. Dimensional Comparison of 21 Typical Aerosol Cover Caps 190
XII The Aerosol Handbook TABLE PAGE 1. Flammable Aerosol Classifications and Precautionary Labeling in Japan 204 2. Flammable Contents of Aerosols Produced in the U.S.A. andtheU.K 206 3. Typical Flammability Test Results 208 4. Required Aerosol Labeling as a Result of Flame Projection Test 210 5. Aerosol Flammability Test Results 213-15 6. Flammability of Selected Hair Sprays by the Flame Projection Test 217 7. Flame Projection Test Results for an Insecticide 218 8. Flash Points of Common Aerosol Ingredients 223 FLAMMABILITY TABLE PAGE 9. Aerosol Flammability Worksheet 227 10. Triboelectric Table of Common Substances 228 11. Electrostatic Charge, Voltage and Sparking Energy for 202 x 406 Cans of Several Aerosol Products 230 12. Variation of Electromotive Force (Voltage) When an Aerosol Is Sprayed and/or Punctured 230 13. Relationship of Capacitance, Electrostatic Charge, Voltage and Sparking Energy in the Threshold Ignition Area 231 14. Minimum Ignition Energy of Various Substances 232 15. Summary of FM Test Results of 1979/80 on Aerosol Prototypes 244 1. Major Categories of Acute Poisoning; 1971 & 1979 255 2. Consumer Attitudes: Problems with Aerosol Hair Sprays 256 3. Acute Inhalation Toxicity of Aerosol Propellents and Solvents 258 4. Incidence of Cardiac Arrhythmia due to Propellent Inhalation 259 5. Threshold Limit Values (TLV) for Various Aerosol Propellents and Solvents 262 6. Material Safety Data Sheet 263, 264 TOXICOLOGY 7. Material Safety Data Sheet for Pressurized Products 265, 266 8. Fee Schedule for Acute Toxicology Studies 267 9. Particle Size Distribution of Hair Sprays 271 10. Falling Rate, as a Function of Droplet Size 272 11. Modified Ames Test Results Using Aerosol Grade Hydrocarbon Propellents 275 12. Results of the Ames Screening Test for Mutagenicity, with Added Carcinogenicity Assays 276 13. Mutation Activity of Various Compounds on Fruit Flies 271 1. Propellent Loss 282 2. Variation of Crimp Depth with Crimp Diameter 288 3. Variation of Crimp Depth with Gasket Material Thickness 288 4. Variation of Crimp Depth with Collet Radius 288 5. Variation of Crimp Depth with Thickness of Valve Cup 288 6. Variation of Crimp Depth with Can Curl Thickness .... 288 7. Variation of Crimp Depth with Bead Contact Height. . . 289 8. Variation of Crimp Depth with Diameter of the Can Opening 289 CRIMPING 9. Variation of Crimp Depth as a Function of Dimensions of Six Factors 290 10. Contact Height Specifications for Various Cans and Valve Cups 293 11. Properties of Flowed-In Gasketing Compounds 295 12. Influence of Crimp Cap Height on Valve Cup Gasket Leakage Rate 296 13. Weight Loss Through Precision Valves, for a Hair Sprayina202 x509Can 301 14. Crimping Dimensions for "Sepro-Cans" and Effects Thereof 304
List of Tables XIII TABLE PAGE 1. Stratospheric Removal of Ozone (Estimated) 312 2. Increase in Carbon Dioxide Volume Mixing Ratio (1800-2020) 314 3. Production and Uses of P-ll and P-12 318 4. Relative Ozone Depletion of CFCs and Certain Chlorofluorocarbons 319 5. U.S.A. Exemptions from the Bans on Chlorofluorocarbon Propellents 320 6. The Commercial Properties of Major Chlorofluorocarbons and Alternate Compounds 321 7. Physical Properties of Fluorinated Hydrocarbon Propellents (Common Types) 324 8. Amounts of Phosgene (mg) Formed by the Pyrolysis of One Gram of Propellents 326 9. Pressure of Pure Fluorocarbon Propellents at Various Temperatures 326 10. Pressure of P-12/P-11 Blends at Various Temperatures . 326 11. Pressure of P-12/P-114 Blends at Various Temperatures 327 12. Glass Cologne and Perfume Aerosol Formulations 328 13. Physical Properties of the Fluorinated Hydrocarbon Propellents (Uncommon Types) 329 14. Borderline Solubility Compositions of P-152a, Ethanol and Water 330 15. Aerosol Propellent Use Profile in Switzerland (1977-1978) 336 16. Pressure Specifications for Aerosol Grade Hydrocarbon Propellents 339 17. Plant Feed and '' Field Grade'' Hydrocarbon Analyses . 340 18. Hydrocarbon Propellent Specifications 342 19. Typical Composition of Aerosol Grade Propellents 343 20. Laboratory Test Results Accompanying Isobutane Shipments 343 PROPELLENTS TABLE PAGE 21. Physical Properties of Purified Hydrocarbon Propellents 344 22. Heat of Combustion for Various Aerosol Ingredients . . . 345 23. Solvent Properties of Propellents and Other Substances 347 24. Conversions Between Mol, Volume and Weight Per Cent for Blends of Propane and Isobutane 349 25. Composition and Physical Properties of N-Butane/ Propane 351 26. Decrease in Pressure as Aerosol Hair Spray is Discharged 351 27. Typical Compositions for Hydrocarbon Propellent Blends Having a Gauge Pressure of 46 psig 352 28. Typical Compositions of the Aeropin Propellents 352 29. Effect of Propellent Selection on the Properties of a Typical Antiperspirant 353 30. Composition and Pressures of Various PIP Propellents .353 31. Particle Size Distribution of an Anhydrous Insecticide Spray 354 32. Specifications for Dimethyl Ether(DME) 355 33. Physical Properties of Dimethyl Ether (DME) 356 34. Solubility and Pressure Development for DME and 25%P-152a/75% DME Mixtures 357 35. Pressure and Density of DME Solutions in Water 358 36. Solubility of C02 and N20 in Selected Solvents 359 37. Flame Projection Results with Dimethyl Ether (DME) Formulas 359 38. Properties of Sym-tetrafluorodimethyl Ether and Perfluorodimethyl Ether 361 39. Physical Properties of Certain Compressed Gas Propellents 362 40. Solubility of CO2 and N2O in Certain Aerosol Liquids and Propellents 364 41. Effect of Methylene Chloride as a Cloud Point Suppressant in Hydrocarbon Type Hair Sprays 370 1. Crimping Efficiency as a Function of Air Withdrawal. . . 423 2. Increase of Metal Ion Concentrations in a Starch Formulation Packed in 202 x 406 Lined Cans Up to One Year 428 AEROSOL LABORATORY 3. Flying Insect Killer, Weight Loss After Actuation - Buna-N Gasket 430 4. Flying Insect Killer, Weight Loss After Actuation - Neoprene Gasket 430 5. Weight Loss Storage Tests 431
The Aerosol Handbook TABLE PAGE 1. Percent Defectives vs. Probability of Acceptance 445 2. Percent Defectives vs. Probability of Acceptance 446 3. Acceptable Quality Levels - Aerosols 446 4. Incoming Inspection Program - Cans 447 5. MIL-STD (Table 11-A) Single Sampling Plan for Normal Inspection 448 6. Incoming Inspection Program - Bottles 451 7. Incoming Inspection Program - Valves 454 8. Incoming Inspection Program - Labels 456 QUALITY ASSURANCE TABLE PAGE 9. Incoming Inspection Program - Caps 457 10. Incoming Inspection Program - Cases 457 11. Physical Methods of Analysis 464-465 12. Chemical Methods of Analysis 465-466 13. X-r Data Tabulation 471 14. Standard Deviation by the Frequency Distribution Method 473 15. Finished Aerosol Analyses 476 1. EPA Product Toxicity Categories for Labeling Purposes 513 2. Type Size of Warning and Precautionary Statements forthe Labeling of EPA Products 513 3. Typical EPA Precautionary Statements by Toxicity Category 4. Application for New Pesticide Product Registration .. . 514 5. Confidential Statement of Formula 516 GOVERNMENT REGULATIONS 6. Label Technical Data 517 7. Certification Statement 518 8. FIFRA S 3(C) (B) Summary Sheet 519 9. Generic Data Exemption Statement 520 10. Labeling Requirements of the FIFRA, as Amended .. . 522 11. Neiss Results on Aerosol Injuries; 1974-1978 with Estimated U.S.A. Totals 534
XV List of Illustrations FIGURE PAGE 1. Aerosol Container Sales in 1980 vs. 1979 12 2. Aerosol Shaving Cream Market Volume 13 3. Aerosol Hair Spray Market Volume 16 4. Aerosol Antiperspirant/Deodorant Market 20 5. Aerosol Perfume Cologne Market Volume 25 6. Aerosol Insecticide Market Volume 28 7. Various Aerosol Fry-Pan Release Products 33 8. A Grouping of Aerosol Food Items 34 MARKETING FIGURE PAGE 9. Difference Between Demand in the Absence of CFC Regulation and Demand with Regulation 35 10. Aluminum Tubes for Personal Protection Products 37 11. Japanese Anti-Static Products for Garments 37 12. World and U.S.A. Aerosol Production 39 13. U.S.A. Aerosol Production 1972-1981 40 14. Packaging of Gillette Products in England 41 15. Translucent 6-Pack Trays Made in England 43 1. Modern and Original "Spra-tainer" 48 2. Cross-Section of #100 ETP, Showing Layers of Tin and Intermetallic Compound 50 3. Dimensions of a Cross-Section of 85# Base Plate with #100/25 Differential Tinplate 50 4. ASTM (Sub. XX) Plate Thickness Survey 52 5. Typical Bottom Double Seam Profile 55 6. Cross-Section of "Snap-lock 202-Dome Top 56 7. Cross-Section of "Snap-lock" 211-DomeTop 56 8. Various Can Bead Profiles 57 9. Configuration of Open and Closed Can Curls 57 10. Proposal for Top End Dimensions for Necked-In Tinplate Aerosol Cans 59 11. The Dual-Radius Can Bottom Profile 59 12. Dual and Single Radius Can Bottoms 59 13. Various Necked-In Varieties of U.S.A. Cans 60 14. Three-Piece Tinplate Welded Side Seam Cams 60 15. AerosolCanof "Flit" and "Aerosect" 62 16. Worksheet Recording Can Evaluation 67 17. Examples of Seamless Can Bodies 71 METAL CONTAINERS 18. Soudronic Wireweld Manufacturing Process 72 19. The Continental 'Conoweld I' Process 72 20. A Personal Product Line, Packaged in Three-Piece Tinplate Aerosol Cans 74 21. Aerosol Products Are Packaged in Standard Cans Varying in Height and Diameter 74 22. Aerosol Can of DOT Specification 2Q. 74 23. One-Piece Drawn Aluminum Aerosol Cans 75 24. Monobloc Aluminum Container 76 25. Monobloc Shaped Aluminum Aerosol Cans 76 26. Shaped Aluminum Aerosol Cans 77 27. Award Winning Aluminum Container 77 28. Aluminum Tube Used For Foam Product 82 29. A Pair of Aluminum Aerosol Cans Produced in France . . 82 30. Aluminum Can Custom Shaped by Alusuisse 83 31. Typical European Designs for Aluminum Aerosol Cans 83 32. Typical Control of a 13 mm Aluminum Tube 83 33. Finish Designs for 20 mm Aluminum Tubes 84 34. Finish Designs: 25.4 mm Tubes, Cans 84
XVI The Aerosol Handbook FIGURE PAGE 35. Typical European 1 " (25.4 mm) Bead for Aluminum Can Showing Machined Section 85 36. Typical Cliff Impact Division 1 " (25.4 mm) Bead for Aluminum Can, Showing Groove 85 37. Progressive Collapse of Aluminum 1 " (25.4 mm) Bead as Pressure Load Increases 85 38. Relationship of Curl Deformation to Pressure Load for 1 "(25.4 mm) Aluminum Cans 86 39. Slugs Used in Making Drawn Cans 87 40. Selection of 15 Monobloc Aluminum Decorated Aerosol Cans 88 41. Unique Aluminum Tube-in-Can Development 89 42. Printing Aera and Other Dimension for Typical Peerasol Cans 89 43. Corrosion Pattern of Water/Ethanol Solutions in Aluminum Aerosol Cans 90 44. Some Tall Commercial Aerosol Cans 93 45. Plain and Lithographed Aerosol Cans 95 46. Exploded Aerosol Can Due to Fire/Heat 97 FIGURE PAGE 47. Cut Away of Three-Piece Soldered Can 97 48. Original Version of RVR Aerosol Can 100 49. Base Section of Aluminum Monobloc Container 101 50. Polyethylene Piston Used in Mira-Flo Aerosol Can .... 102 51. ATypical Early "Sepro-Can" 103 52. Kartridg Pak's "Sepro-Can" Unit for Under-The-Cap Gassing 104 53. Bag-in-Can System Offered in Europe 106 54. Polyethylene Bag for Alupress-Pack 106 55. The Alu-Compack Composite Aerosol System 107 56. Bag-in-Can Development from Switzerland 107 57. Alucompack System for Toothpaste Product 107 58. Cross Section of Alucompack Dispenser 108 59. Coating, Filling and Use of "Flip" Barrier Pack Cans . . 108 60. Piston Used in the "Pepo" Ecological Aerosol Container, Belgium 109 61. The "Preval" Spraymaker 110 GLASS AEROSOLS 1. Glass Colognes 112 2. Dimensions; Finish of 20 mm Glass Aerosols 114 3. Coated Glass Cylinder Rounds by Wheaton Aerosols Company 115 4. Glass Bottles by Risdon Corp 124 1. Plastic and Glass Aerosol Containers 138 2. Cologne in Celcon Bottles 139 5. Original Stock Design Aerosol Bottles by Carr- Lowrey Glass Co 125 6. Bottles Described in Table V, in Relation to Breakage Resistance 127 7. Manual Glass Aerosol Production Line 131 8. Clear Glass Bottle Prior to Fall Labeling 135 PLASTIC AEROSOLS 3. Sketch of OPET 140 4. 1982 Prototype of OPET Bottle 141 1. Flat and Conical Valve Mounting Cups 151 2. Cross Section ofa Flat Cup and Conical Cup Valve ....152 3. Cross Sectional View, Showing Aerosol Valve with Stem Gasket and Cup Gasket Eudiometers 158 4. Model CL Valve 166 VALVES 5. Seaquist NS-31 Aerosol Valve Assembly 170 6. Seaquist PF-71 Toggle Valve Assembly 170 7. S-63 Tilt Valve by Summit Packaging Systems 170 8. Diagrams Showing Valve Action in Open and Closed Positions 171
List of Illustrations XVII FIGURE PAGE 9. Exploded View of CA-78 Female Aerosol Valve 173 10. Seaquist SF-91 Female Valve Assembly 174 11. Standard and Metering Ferrule Type Aerosol Valves by the Emson Research, Inc 176 12. Schematic Drawing of CLF Valve 177 FIGURE PAGE 13. Variable Aerosol Actuator Operation 177 14. Aquasol Dispenser Stem and Sprayhead 178 15. Two-Piece Specialty Actuators 179 16. CliXon Dispensing Cycle. Also a Spray vs. Time Profile 179 COVER CAPS 1. Slotted Cover Cap with Extension Tube 184 2. Drawing of Old Style One-Inch Cap 185 3. Drawing of Double Shell Cap 185 4. Drawing of Rim Snap Cap 185 5. Drawing of Snap Lock Cap 185 6. "Lift-Up" Cap 186 7. European Cap 191 8. Aerosol Cover Cap Fitment Gauge 191 9. Fitment on a Necked-In Can 192 10. Detail on 207.5 Diameter Snap Lock Cap 192 11. 114-Diameter Can Necked-In to a 112 Can 193 12. Selection of Anodysed Aluminum Caps 194 13. Mark Series Caps by Metal Box Ltd 194 1. Flame Consequences of Spraying 207 2. UN Certification Marking 208 3. Australian Flame Projection Test Unit 209 4. Canadian Flame Projection Tester 209 5. U.S.A. Flame Projection Testing Device 211 6. Flame Projection Diagram 216 14. Full Diameter Cover Cap 195 15. KinderGuardTM 196 16. Overcaps by Knight Engineering & Molding Co 196 17. Modified Summit S-63 Valve and Heavy Duty Actuator/Overcap Used for Tire Inflation 197 18. Precision Valve Actuator Caps 197 19. Hemishperical Cover Cap Design 197 20. Customized Cover Caps and Actuator Cap on Aluminum Cans — European Market 198 21. Ordinary Tinplate Can and Cap, Compared with Brushed Aluminum Can and Cap 198 22. Blendax Aerosol Toothpaste in Composite Aluminum Tube, Custom Cap, Spout and Base in Shadow-Box, Sold in West Germany 198 FLAMMABILITY 7. Closed Drum Test Apparatus 220 8. Modified Tagliabue Open Cup Flash Point Tester 221 9. Flammability of Surface Residues Tester 224 10. Apparatus for Measuring Static Charge 229 11. Warehouse Fire Involving Aerosols 242 12. Graph Charting Flammable Storage Hazard 247 1. Biotransformation of Methylene Chloride 260 2. Biotransformation of N-Hexane 260 3. Chart of Exposure to Methylene Chloride 261 4. Time-Related Divisions of Toxicological Testing 267 5. Cross-Section View of the Human Respiratory System . 268 TOXICOLOGY 6. Deposition of Airborne Particles in the Respiratory Tract, Shown as a Function of Aerodynamic Dynameter 269 7. Retention of Aluminum Chlorohydrate in the Lungs . . . 269 8. Particle Size Distribution of Anhydrous Insecticide ....273
XVIII The Aerosol Handbook FIGURE PAGE 1. Split Ring and Nut, for Temporarily Sealing Aerosol Valves 283 2. Closed and Open Curl Configurations 284 3. Open and Closed Curl Configuration 10X Magnification 284 4. Open and Closed Curl Configurations 20X Magnification 284 5. Dimensions Surrounding Crimped Can Curl 286 6. Device to Determine the Throat Radius of the Can Dome 289 7. Can Dome and Upper Body Section of 211 Can 290 8. Valve, Dome and Upper Portion of Aerosol Can 290 9. Device to Determine the "Point of Hard Contact" 290 10. Sketch Illustrating Point of Hard Contact 291 11. Gauge to Measure Contact Height 292 12. Gauge for 1 Inch Valve Cup Flowed-In Gasket 294 CRIMPING FIGURE PAGE 13. Device for Determining the Gasket Thickness 295 14. Kile Crimp Diameter Gauge with Slotted Turret 297 15. Eight Segment Crimping Collet 297 16. Device for Measuring Valve Cup Inside Diameter 298 17. Shoulder Profile of Aluminum Can 299 18. Glass Aerosol Valve Correctly Crimped 300 19. Incorrectly Crimped, Too Loose - Latent Leaker 300 20. Incorrectly Crimped, Too Tight and High 300 21. Kile Gauge for Measuring Crimp Diameter 302 22. Kile Aerosol Crimp Depth Gauge 302 23. Kile Aerosol Can Throat Contour Gauge 303 24. Graph On Throat Profile 303 25. Inner Throat Profile for 202-Diameter Can Before and After Crimping 303 PROPELLENTS 1. Concentration Profile of Atmospheric Ozone 311 2. Percent Distribution of Stratospheric Ozone 313 3. Total Ozone Over the Northern Hemisphere 316 4. Pressure of CFC-11/12 Mixtures with Ethanol 325 5. Density of CFC-11/12 Mixtures with Ethanol 325 6. Pressure ofP-12/Ethanol and P-114 Ethanol Mixtures . .328 7. Vapor Pressure vs. Temperature for Fluorocarbons P-113,P-114andP-115 329 8. Pressure and Phase Diagram for Blends of Ethanol, Water and P-152a 331 9. Pressure for Blends of P-152a/Isobutane and P-152a/ P-133a 332 10. DensityofP-142band 152aat Various Temperatures ..333 11. Pressure of P-142b and P-152a at Various Temperatures 333 12. Pressure of Common Halons and Blends 334 13. Density of Common Halons and Blends 334 14. Anti-Perspirant Transfer Efficiency 335 15. Refiners and Resellers of Aerosol Hydrocarbon Propellents 337 16. Field Grade and Aerosol Grade Prices of the Common Aerosol Hydrocarbon Propellents 338 17. Butane Purification Facility 341 18. G/L Chromatographic Analysis of Aerosol Grade Isobutane 343 19. Pressure of Hydrocarbon Propellents at Various Temperatures 346 20. Density of Hydrocarbon Propellents at Various Temperatures 346 21. Solubility of the Ethanol, Water & Isobutane System at 70°F 346 22. Pressure of Propane/Isobutane Propellents at Various Temperatures 350 23. Density of Propane/Isobutane Propellents at Various Temperatures 350 24. Pressure of CO2 and N20 Propellents at Various Temperatures 362 25. Density of CO2 Propellent at Various Temperatures ...362 26. Pre-Saturation Equipment for the Addition of CO2 or N20 to Aerosols 368 27. Effect of Methylene Chloride on the Cloud Point of Aerosol Hair Sprays 369
List of Illustrations XIX FIGURE PAGE 1. Floor Plan for a Typical European-Style Filling Plant with Two Lines and Provision for a Third 376 2. Propellent Blending System 378 3. Plastic Container Carrier Pucks 380 4. A Manual Type Production Filling Operation 381 5. Single and Double Row, Double-Indexing Lines 382 6. Rotary Line with Filler/Crimper/Gasser Machine 382 7. Double-Indexing Aerosol Loading Line 382 8. High-Speed In-Line "Core Assembly" Machine - the Heart of an Aerosol Line 383 9. StarPakM20by Aerofill, Ltd 383 10. Rotary Filling Machine with Water Bath 383 11. Layout for Lehn & Fink Hi Speed Line for Packaging Lysol 384 12. Product Acceptability vs. Weight of Propellent A-46 for a 2 Av. Oz. Shave Cream 385 13. Lay-Out of an Aerosol Production Line Designed to Run One Product, at About 100 CPM 386 14. High Flexibility Production Line 387 15. A Simple Rotary Line, Rated at 120 CPM 387 16. Economical Tray-and Disc Can In-Feeder Unit 388 17. Nalbach Semi-Automatic Can Depalletizer 389 18. Nalbach Model 16-RS Food Aerosol Machine 392 MACHINERY FIGURE PAGE 19. Terco Inc. Indexing Rotary Filling Machine 393 20. Terco Inc. Rotary Aerosol Filling Machine (40 CPM) 393 21. Nalbach Tube and Glass Aerosol Filler and Crimper . . . 394 22. Kartridg-Pak Automatic Valve Sorter and Inserter ....395 23. Comparison of Theoretical and Typical Can Evacuations 396 24. Terco Inc. Hand-Operated Filling Machine with Production Heads 397 25. Elaborate Chlorofluorocarbon and Hydrocarbon Propellent Tank Farm 398 26. Floor Plan of Gas House 398 27. Nalbach Model HPC Aerosol Propellent Charger 399 28. Can Evacuation, Filling and Crimping Sequential Operations of a Kartridg Pak U-t-C Gasser with Nine- Head Frame 400 29. A Typical Kartridg Pak U-t-C and Saturator Layout . . . 401 30. Propellent Supply System to Kartridg Pak U-t-C Gasser 402 31. The Nalbach Sepro-Charger Accessory to Their Various Rotaries 403 32. Nalbach Double-Row Hot Tank and Can Blower 405 33. Nalbach Model 1-L1 Hot Tank, Showing Water Heater and Pump 406 34. Nalbach Rotary Cap Placer Machine with Cap Sorter . . 407 AEROSOL LABORATORY 1. Statistics of New Product Development 411 2. Comparison of 0.10#ETPand0.25#ETP Steel Plate. . .412 3. Peterson/Puritan Laboratory, Main Floor 419 4. Peterson/Puritan Laboratory, Second Floor 420 5. Peterson/Puritan Food Pilot Line 420 6. Flame Propagation Tester. FEA X-601 421 7. Flame Extension Measurement Apparatus 421 8. Valve Delivery Rate Tester 422 1. Hold Release Report 441 2. Rejection Report 442 9. Graph of Air in Liquid and Vapor Phases 424 10. and 10 A. Pressure Burettes 434 11. Aerosol One-Inch (25.4 mm) Valve De-Crimper 435 12. Precisionaire Valve Tester 436 13. Aerosol Spray Testing Apparatus 436 14. Spring Force Tester 436 15. Can Curl Meter 437 QUALITY ASSURANCE 3. Supplier's Downtime Report 443 4. Operating Characteristic Curve 445
XX The Aerosol Handbook FIGURE PAGE 5. Operating Characteristic Curve 446 6. Micrometer for "G" Dimension 450 7. Gauge for Baseweight of Metal 450 8. Gauge for Height of Valve Cup 450 9. Custom Made Valve Stem Height Tester with Dial Micrometer Readout 451 10. Measuring Crimp Diameter 451 11. Gauges for Crimp Measurements 451 12. Quicktest Crimp Micrometer 452 13. Gauge for Double Seam Height 453 14. "Go/No-Go" Stem HeightGauges 453 15. CSMA Gauge for "A-D" Dimension 453 16. Oditest Gauge for Can Bead 453 17. Incoming Inspection Report 458 18. Reject Inventory Adjustment 459 19. Typical Label for Batch Samples 460 20. Raw Materials Analysis Form 461 21. Compounding Instruction Sheet 462 22. Batch Record Sheet 463 FIGURE PAGE 23. Certificate of Analysis 463 24. Production Data 467 25. Filling, Gassing Reports 468 26. Quality Control Chart 468 27. Checkweigher Report 469 28. Salvage Report 469 29. Inspector's Daily Report 470 30. Supervisor's Shift Report 470 31. Roving Inspector's Check Sheet 470 32. Statistical Treatment of Data 471 33. X-r Chart for Weight Control 471 34. Chart of Assignable Causes 472 35. Frequency Distribution Chart 474 36. Standard Deviation Chart 474 37. End of the Line Report 475 38. Flowed-In Gasket Analysis 477 39. Batch and Finished Product Analysis Report 479 40. Label for Retainer Samples 484 TEST METHODS Apparatus for Tower Method 487 Apparatus for Trough Method 488 Tag Open Cup Tester 489 Glass Test Cup 489 Leveling Device for Adjusting Liquid Level in Test Cup 490 Layout for Sample Labels 524 Disinfectant Sample Label 527 A-D Valve Dimension 492 A-D Measuring Gauge 492 Furniture Polish Evaluation Form 496 Identification of Can Dimensions 501 GOVERNMENT REGULATIONS Insecticide Sample Label 528 Danger Symbols 544
Contents List of Tables x List of Illustrations xv Introduction 1 1. Aerosol Marketing Considerations 5 Scheduling a Product Introduction 7 Consumer Profiles 11 Consumer Attitudes 11 Marketing Strategies 13 Shaving Creams 13 Hair Sprays 16 Antiperspirant Sprays 20 Perfumes and Colognes 24 Skin Care Aerosols 26 Insecticides 27 Cigarette Lighters 29 Insect Repellents 29 Furniture Polishes 29 Paints, Coatings and Finishes 29 Laundry Aids 30 Air Fresheners 30 Home Insulation Aerosols 31 Food Products 32 Aerosol Production 35 The Marketplace 41 Packaging Considerations 42 Marketer's Packaging Check List 42 [This page has been leformatted by Knovel to provide easiei navigation. yjj
viii Contents Cost Considerations in Aerosol Production 44 The Aerosol Advantage 46 2. Metal Aerosol Containers 47 Steel and Tinplate Containers 48 Temper 54 End Unit Construction 55 Body Fabrication Techniques 63 Can Linings 63 Side Seam Construction 69 U.S.A. Two- and Three-Piece Tinplate or Steel Cans 74 Aluminum Containers 75 Production of Aluminum Aerosols Cans 86 Linings 87 Decoration 87 Label Dimensions and Print Areas 89 Corrosion Aspects of Aluminum Cans 89 Production of Aluminum Aerosols 91 Commercial Aspects of Aluminum Cans 92 Stainless Steel and Other Aerosol Containers 92 The Paper Labeling of Aerosol Containers 93 Lithographic Decoration 94 Container Shaping 96 Aerosol Can Safety Devices 97 Compartmented Aerosols Cans 101 The Sepro-Can 102 The Presspack System 105 The Alupresspack System 106 The Microcompack and Alucompack Systems 106 The FLIP System 108 The Enviro-Spray System 109 Other Barrier Packs 109 [This page has been leformatted by Knovel to provide easiei navigation.
Contents ix 3. Glass Aerosols 111 Manufacture of Glass Aerosol Bottles 112 Decoration of Glass Containers 116 Pressure Considerations 116 Glass Aerosol Bottle Designs 122 Uncoated Glass Aerosol Designs 122 Plastic Coated Glass Aerosol Designs 123 Glass Aerosol Testing Procedures 124 Total Visual Inspection 125 Internal Pressure Testing 125 Drop Testing 127 Comprehensive Load Testing 129 Thermal Shock Testing 129 Impact Testing 129 Characteristics Interfering with Coatings 130 Glass Distribution Testing 130 Capacity Testing 130 Filling Glass Aerosols 131 Compounding the Concentrate 131 Filling, Air Removal and Crimping 132 Gassing 134 Hot Tanking 134 Labeling 135 Marketing Summary 136 4. Plastic Containers 137 TheOPET Plastic Container 139 Other Modern Plastics 142 Properties of Plastic Aerosols 142 Fabrication 142 Decoration 142 Size and Weight 143 [This page has been leformatted by Knovel to provide easiei navigation.
x Contents Design 143 Staining 144 Impact Resistance 144 Safety 145 Organoleptic Compatibility 145 Permeation 145 Chemical Compatibility 147 Marketing Aspects 148 Future 148 5. Aerosol Valves 149 The Vertical Action Aerosol Valve 150 Actuator 150 Mounting Cup and Cup Gasket 151 Gasket Leakage Considerations 157 Stem Gasket 163 Valve Stem 164 Valve Body 165 Spring 166 Dip Tube 167 Vertical Valve Assemblies 169 The Toggle Action Aerosol Valve 170 The Female Aerosol Valve 172 Ferrule Type Aerosol Valves 174 Special Components or Accessories 176 One-Shot Valves 176 The VariSeal Aerosol Actuator 177 The Aquasol and Aquamist Systems 177 Special Applicators 178 Suggested Valves for Various Products 181 Future 181 [This page has been leformatted by Knovel to provide easiei navigation.
Contents xi 6. Cover Caps 183 Cover Cap Dimensions 187 Custom Caps 193 Actuator Caps 194 Child Resistant Caps 195 Specialty Caps 196 Decoration Techniques 197 7. Flammability 199 Aerosol Flammability Regulations in Japan 203 Aerosol Flammability Regulations in Europe 204 Aerosol Flammability Recommendations by the UN 208 Aerosol Flammability Regulations in Australia 209 Aerosol Flammability Regulations in Canada 210 Aerosol Flammability Regulations in Argentina 211 U.S.A. Flame Projection Test 211 U.S.A. Closed Drum Test 220 Modified Tagliabue Open Cup Flash Point Test 221 Surface Flammability Tests 223 Foam Flammability Tests 225 Composite Flammability Tests 226 Electrostatic Flammability Hazards 227 Precautions Against Triboelectric Ignitions 231 Reformulation 231 Production Precautions 232 Aerosol Flammability in Plants and Warehouses 234 Safe Handling of Aerosol Concentrates 234 Safe Handling and Gassing of Hydrocarbons 236 Unloading, Storage and Handling System 236 TheGassingRoom 237 Warehouse Storage of Aerosols 239 The Factory Mutual Initiative 240 Product Reformulation 246 [This page has been leformatted by Knovel to provide easiei navigation.
xii Contents Warehouse Storage of Aerosols - International 248 Safe Disposal of Aerosol Containers 249 8. Toxicology 253 Acute Toxicity 254 Cardiac Arrhythmia 258 Biotransformation 259 Acceptable Limits of Exposure 261 Material Safety Data Sheets 262 Sub-Acute Toxicity 267 Sub-Acute Inhalation 268 Aerosol Vasodilators or Antiasthmatics 270 Biological Consequences of Inhalation 270 Sub-Acute Dermal Toxicity 274 Chronic Toxicology 274 Sub-Acute Oral Toxicity 274 Teratogenic Studies 274 Mutagenic Studies 275 Carcinogenic Studies 277 Retrospective Epidemiological Toxicology Surveys 279 9. Crimping 281 General Considerations 282 Crimping Specifications for Metal Cans 286 Gasket Material Thickness 288 Collet Foot Thickness 288 Thickness of Tinplate Valve Cup 288 Can Curl Thickness 289 Diameter of the Can Opening 289 Calculation of Crimp Depth 291 Contact Height of Can Bead 291 Flowed-in Gaskets 293 Causes of Container Leakage at the Crimp 298 [This page has been leformatted by Knovel to provide easiei navigation.
Contents xiii Measuring Finished Crimp 301 10. Propellents 305 The Chlorofluorocarbons Propellents 307 Rowland and Molina Theory 308 Preliminary Atmospheric Chemistry 310 Empirical Ozone Measurements 315 Regulatory Activities 317 Costs of Conversion to Alternate Propellents 320 Properties of the CFC and FC Propellents 323 The Alternate CFC and FC Propellents 330 The Bromochlorofluorocarbons and Bromofluorocarbons 334 The Hydrocarbons Propellents 335 Purification of Field Grade Propane, n-Butane and Isobutane 339 Inspection of Purified Propane, n-Butane and Isobutane 342 Properties of the Aerosol Grade Hydrocarbons 344 Blends of Hydrocarbon Propellents 349 Ether Type Aerosol Propellents 354 Purity and Physical Properties of DME 355 Solubility Aspects of DME 357 Flammability of DME Formulations 359 Methylethyl Ether and Diethyl Ether 360 Bis(Difluoromethyl) Ether and Bis(Trifluoromethyl) Ether 361 Compressed Gases 361 Toxicological Considerations of C02 and N20 366 Production Aspects of C02, N20 and N2Gases 366 Methylene Chloride 368 Specialty Gases that Function as Propellents 371 11. Production Equipment 373 The Aerosol Production Line 379 Individual Production Equipment Items 388 Can Depalletizers and Other in-Feed Equipment 388 [This page has been reformatted by Knovel to provide easier navigation.
xiv Contents Can Cleaners 389 Can Coders 389 Can Counters 390 Powder Filler 390 Liquid Concentrate Fillers 391 Checkweighers 394 Valve Inserters 394 Valve Crimper 395 Propellent Gassers 397 Hot Tank 405 Tipping Machines 406 Capping Operations 407 Aerosol Can Packaging 407 Future Aerosol Filling and Packaging Equipment 407 12. The Aerosol Laboratory 411 Formulation 414 Lay-Out of an Aerosol Laboratory 419 Equipment Requirements 420 Laboratory Techniques 422 Product Use Tests 431 Product Economics 433 Specialized Equipment for Aerosol Testing 434 Reed Valve Torque Tester 434 Pressure Burettes 434 Hydrostatic Bursting Unit for Aerosol Cans 435 Can Puncturing Device 435 Va Ive Th ickness Ga uge 435 Aerosol Decrimper 435 Valve Delivery Rate Tester 436 Aerosol Spray Test Apparatus 436 Spring Force Tester for Aerosol Valves 436 Device for Measuring Crimping Force 436 Meter for Checking Mechanical Stability of Aerosol Can Curl 437 [This page has been leformatted by Knovel to provide easiei navigation.
Contents xv 13. Quality Assurance 439 Organizational Relationships 440 Scope of Quality Control Operations 441 Establishment of a Quality Assurance Program 443 Scientific (Statistical) Sampling 444 Incoming Inspection of Cans 447 Incoming Inspection of Plain and Plastic-Jacketed Glass Bottles 451 Incoming Inspection of One-Inch Cup Valves 453 Incoming Paper or Paper-Backed Foil Labels 455 Incoming Inspection of Overcaps 456 Incoming Inspection of Corrugated Shipping Containers 456 Incoming Inspection - Final Comments 458 Inspection of Chemicals 459 Quality Assurance During Compounding 462 Manufacturing Procedures 463 Process Control Procedures 469 Inspection of Finished Aerosols 475 Special Projects 478 Current Good Manufacturing Practices 478 Summary 479 Regulations in South America 484 14. Test Methods 485 Revised Flammability Test Methods for Aerosol Products 485 Tentative Method for Determining the Relative Flammability of Aerosol Foam Products 486 Flash Point Determination 488 Tentative Method for Measuring "A-D" Dimension of Aerosol Can Valves 492 Procedure for Evaluation of Combing Characteristics of Hair Spray Formulations 493 Determination of the High Humidity Curl Retention of Aerosol Hair Sprays 494 Determination of the Pressure (or Vacuum) in an Aerosol Container 495 Tentative Method for Furniture Polish Evaluation 497 Military Standard Sampling Procedures MIL-STD-105D 498 [This page has been reformatted by Knovel to provide easier navigation.
xvi Contents Tin Plate Fabricated Aerosol Cans 501 Method for Determining Delivery Rate of Aerosol Products 501 15. Government Regulations 503 The Food, Drug and Cosmetic Act 505 Fair Packaging and Labeling Act of 1966 510 The Environmental Protection Agency 511 The Federal Insecticide, Fungicide and Rodenticide Act of 1947 511 Federal Environmental Pest Control Act of 1971 529 The Toxic Substances Control Act 530 The Resource Conservation and Recovery Act Consumer Product Safety Act 531 Clean Air Act 531 Consumer Product Safety Act of 1972 532 The Federal Hazardous Substances Act of 1960 532 The Poison Prevention Packaging Act of 1970 533 The CPSC National Electronic Injury Surveillance System 533 CPSC Aerosol Ingredient Labeling Program 534 Other CPSC Activities 535 The Occupational Safety and Health Act of 1970 535 Department of Transportation (DOT) 537 The U.S. Department of Agriculture (USDA) 539 State Regulations 539 Regulations Concerning Weights and Measures 540 European Regulations 541 Net Contents 541 Transportation 542 Regulations Outside the U.S.A. and Europe 543 16. Buyer-Seller Relationships 545 Product Safety Warranty 545 Container Warranty Agreement 550 Confidentiality Agreement 551 [This page has been reformatted by Knovel to provide easier navigation.
Contents xvii 17. Aerosol Contract Fillers 553 18. Aerosol Marketers 569 AAPRI Cosmetics INC ... Jean Patou INC 569 Jericho Laboratories ... Zynolyte Products CO 592 Trademarks 617 Appendix 633 Industry Trade Terms and Abbreviations 633 Company Listings 638 Index 642 This page has been reformatted by Knovel to provide easier navigation.
AEROSOL MARKETING CONSIDERATIONS 5 1 Marketing has been defined as the management process responsible for identifying, anticipating and satisfying customer requirements profitably. To do well at marketing, a company must evaluate constantly its resources and match them to the environment in which it operates. Marketing is by no means restricted to those firms whose products are presented to the consumer on the store shelf, by mail order or by the door-to-door salesperson; it is a ubiquitous force, being applied by every successful company as its marketing experts assess the realities and potentials of their customer mix. The marketing operation may begin with the flash of inspiration that heralds the development of a new or improved product. It acts to regulate and systemize that development through the myriad of steps required to bring the product to the point where the consumer purchases it. Marketing is a very big business. During the last decade, the number of new consumer products increased from 26,000 to 37,000 per year, at research and development costs of over $17.5 billion. As imposing as this dollar figure may seem, it is still only a small part of the capital that U.S.A. companies must lay out during the evolution of new products and packages. The advertising and promotional budget for a full-scale national program normally starts at $10 to $14 million. New products form an increasingly demanding aspect of corporate decision-making. The high impact and complexities of technical and marketing developments have brought about a virtual condition of sink or swim in the marketplace, and there is less financial room for errors than ever before. The whole world loves a gambler—when he is successful. For a company not to introduce new products, better products, new services or new economies is to be unloved, particularly on Wall Street, and unwanted by talented creative people as the corporate entity withers. New marketing thrusts, then, are essential, even though the cost of failure can be disastrous. (In 1981 the failure of a feminine protec-
6 The Aerosol Handbook Table I U.S.A. Production of Consumer Retail Packages Plastic Bottles Glass Bottles Collapsible Tubes Metal Plastic Metal Cans General Line Sanitary Beer & Beverage Aerosol Paper, Foil & Composites Units Produced 1971 6.0 41.0 1.44 0.06 10.0 31.0 37.0 2.8 177.0 (Billions)* 1980 9.7 47.1 1.2 0.13 4.9 30.0 54.4 2.4 286.0 "Estimates from various sources. Packaging cost $47 billion at the manufacturing level in 1980. tion product cost $90 million.) In the whole complex maze of product introduction and maintenance no one is more important than the marketing director. In the larger companies, new product marketing activities are aided by inputs from research, engineering, manufacturing development, packaging and cost accounting. Outside agencies are increasing contributions in such areas as advertising, package design, clinical testing and brandname selection. Smaller roles are played by quality assurance, sales and legal departments. In the smaller company, the marketing executive is often forced to go outside for nearly everything. Historically such firms have often turned to contract fillers, taking advantage of their years of experience in formulation and packaging areas. For a large, nationally oriented product introduction program, the time for completion will take from one to four years, up significantly from the time frames of a decade ago in the 1970s when things were simpler and less regulated. The longer programs may come about through the need for exhaustive clinical testing, the satisfaction of EPA or FDA requirements, unanticipated complications, or even new developments that may make it necessary to restructure the schedule. In one interesting case, an aerosol pancake batter product was developed during a three year period. During this time, however, the priorities of the marketing department changed. It was realized that a $900,000 batter processing system would have to be installed, and a study of breakfast eating habits showed a steady decline in the consumption of pancakes. The project was killed. There is nothing small about the consumer packaging market. Packaging costs are now about $49 billion for 1981 at the supplier level, up from $22 billion in 1971. The 1981 figure translates to a retail level close to $85 billion. About 4,600 manufacturers make the containers and employ roughly a million workers in the process. The final package is put together in some 300,000 filling and packaging plants, with a gross output of around 370 billion units per year. A breakdown of the various container types is given in Table I. Sir Francis Bacon once said, "Figures can be likened to streetlamps: they can serve both to illuminate the written word and provide support for the weary writer." (Market statistics included.) Our purpose in reporting these numbers is to show the truly massive dimensions of the U.S. packaged commodity market, with aerosols showing up as somewhat less than 1 %. An interesting contrast can be shown by examining the toiletries packaging market, which is only about 2 % of the total, but where aerosol containers make up the largest category. A comparison of the various container types is given in Table II. The future advances will be derived from the technical developments now underway. Programs designed Table II U.S.A. Production of Toiletries Retail Packages* Plastic Blow-Molded Bottles Glass Bottles Collapsible Tubes Metal Plastic Aerosol Cans Boxes Folding Set-Up Closures Total Annual Rate Of Increase (Per Cent) Units 5 0 2 5 4 4.5 (2) — — Dollars 17 11 12 17 14 14.5 8 15 7.5 Dollar Shipments to Mfgrs. (Millions) 1980 212 54 27 23 302 151 5 119 893 1985 465 91 48 50 581 294 4 240 1773 "Estimates from Frost & Sullivan, Inc.
Aerosol Marketing Considerations 7 to reduce energy consumption, improve recyclability, produce higher quality and lower cost decoration, improve tube laminations, provide easier opening and dispensing closures, improve gas barrier resins for plastic bottles and so forth will all help determine the upward pace of the market. Many improvements for aerosol cans and valves are in progress and are described in later chapters. Scheduling A Product Introduction These days the introduction of a new product involves thousands of individual steps taken by hundreds of people. A central master plan must be evolved to schedule and control this myriad of steps and operations, so that they can be completed in a minimum of time and at the least expense. The PERT (Project Evaluation and Review Technique) is used by many firms to achieve these objectives. Although PERT was designed originally as a computer system and used by the Navy to develop the Polaris missile, the method can be described in such simplified terms that it can be understood and administered without the need for either a computer or extra personnel. In the simplified PERT system, a series of circles, squares or rectangles is used to designate a specific operation which is a part of the overall program. The job description is written inside. The diagram normally flows from left to right, using a backbone of key operations to build upon. A series of such key points would be, for example: a. Marketing motivation (The beginning of it all.) b. Marketing plan c. Creation of the package d. Development of final formula and specifications. e. Test market approval f. National program approval g. Full production h. Consumer purchase The accentuated key operation points are connected up by means of a large number of secondary operations. For instance, test market approval starts a sequential chain of events involving: a. Elaborate test market planning. b. Placement of advertising in various local media. c. Personal contact with test stores. d. Ordering chemicals and packaging. e. Production and shipment to test stores. f. Package performance evaluation. g. Evaluation of test market results. h. Possible revision of product according to marketing analysis. i. Final production costs established. The objective of this program: that a national marketing program can be established. In some diagrams, the above chain will not necessarily be sequential. If a delay is anticipated with the production operation, supplies can be purchased for the run even before test market plans are finalized. In some cases this may lead to back-up production, or an excess of merchandise, but the time saved will often be worth the risk. Arrows are used to link up sequential operations, and proposed time to complete each step is posted above the arrows. It is convenient to indicate time in weeks and decimal fractions of weeks, but some PERT networks are timed in days. A few PERT diagrams are drawn with strict attention to time as the X-axis, or abscissa; thus keeping time coordination between operations on an easily viewed basis. The various circles or squares are often circled in red as they are completed. Auxiliary PERT diagrams, which can be looked upon as insets on the primary one, are made usually where more detailed development is needed for a particular situation, such as the purchase of all the chemicals and packaging components for the test market product. An outstanding example of a marketing type PERT diagram is given in Modern Packaging Encyclopedia, 1971 issue; page 47. Network planning is rapidly becoming popular with marketing directors and package development executives, since it tells them exactly where the project stands. The chart indicates the time schedule, shows what may have gone wrong (if anything), and provides the necessary interrelationships — who has to do what before something else can be done. The primary benefits are avoidance of unnecessary delays and expenses. Another benefit is that minor contributory points will not be overlooked. Two pitfalls, both minor, have come to light: if the timing on the chart is too generous, no one will finish ahead of schedule, and if the network is all nicely drawn and organized, few people will risk antagonism by proposing meaningful improvements. Both can be minimized by an alert marketing executive.
8 The Aerosol Handbook Any good product introduction program will benefit from the creation of a Packaging Committee as the central organizational feature. The committee should be composed of experts on construction, graphics, scheduling and so forth, and should have the power to make approvals in the absence of top managers. Committee activities also help cut snags in communications and lessen the need for lengthy report writing. The key people, working with the project day by day, attend these meetings. They will surely note things of interest. The interplay between these packaging experts often results in significant improvement of the final product. Marketing people must keep in mind the thought that every new product must start and finish with the consumer. Here, regardless of all else, it must be able to stand on its merits. The finest marketing program, the best package, the most effective formula, will all go down in ruin if the soverign consumer remains unimpressed. New product ideas must be encouraged constantly from all sources, particularly suppliers. Speed is vital in product introduction. Be first if at all possible. Nielsen has made a 15 year study of the sales record of "pioneer brand" versus that of followers. The first follower gained only 51 % of the sales volume of the first brand after three years, while the second follower managed only 25%. It is also essential to work within clearly defined corporate objectives and business realities. The new product must have the hearty sanction of top management. There are too many cases where middle executives have worked many months on a new product, only to have it killed during a Board of Directors meeting. Many new products are carried to the market on three waves of activity, each more costly than the last. In the first stage, sometimes called the initial assessment, the idea is submitted to a generalized scanning process, aimed mainly at deciding whether the project should be subjected to further and more intensive study. A PERT diagram or a simple listing of requirements will suffice at this stage. Some typical check points are: a. Is the product consistent with consumer needs or desires? b. What precisely is the new product concept and how does it perform? c. What type of customer would likely purchase? d. What is the marketing platform in relation to: i. Population of probable consumers. ii. Market statistics. iii. Market experience of other firms with similar products. iv. Competitive position. v. Price policy. vi. Cost of advertising. vii. Rate of product obsolescence. e. Do distributional channels pose any problems to the company? f. Can the sales force effectively sell the product? g. Is the formula available? i. Is the formula free of patents, royalties or other encumbrances? ii. Is the formula well tested for compatibility and safety? iii. Is the formula exclusive in any way? h. Do production requirements pose any problems? i. Are there any legal or registrational difficulties? j. Is the development program capital intensive? k. Does the development and marketing of the product conform to broad corporate objectives? If the proposed new product passes muster at this level, then it is generally qualified for second stage assessment — a much more searching scrutiny over a broader field. At this stage, the inquiry must become strongly consumer oriented. Sequential check points can be listed as: a. Organize the facts by preparing a brief covering: i. Rationale for introduction. ii. Proposed brandname(s). iii. Description of quality requirements, iv. Estimated cost structure. v. Anticipated problems, if any. b. Examine advertising concepts, aided by small- scale panel testing. c. Survey all existing information concerning the desired market area, consumer buying habits and important product attributes. Conduct market surveys to fill in any missing data. d. From the above, determine the approximate consumer rating of the proposed product versus competition.
Aerosol Marketing Considerations 9 e. Define as accurately as possible the estimated market size and value. f. Estimate competitive brand shares. g. Estimate competitive expenditures (both present and future) compared with those of the new product. h. Determine marketing position. i. Is the brand aimed at becoming a leader? ii. Is the pricing to be highly competitive? iii. Is the product designed to fill an unfilled marketing need? iv. At what level should the sales estimate and advertising budget be set? v. What is the laboratory's assessment of the advantages of the product over competition. Can they be dramatized? vi. What is the consumer's assessment, based on small panel tests? vii. What is the pull of the proposed brand- name? viii. What have been the results of any similar introductions either in the U.S.A. or abroad? ix. What is the strength of competition? What are the weaknesses? x. Are distributional networks available? xi. Are trade margins favorable? i. Check availability of packaging components and chemicals. j. Outline a complete quality assurance program. k. Check production methods; possible problems. 1. Ascertain preliminary direct costs, delivered to warehouses. The final stage involves the decision to launch, with all the attendant complexities. A PERT network becomes essential from this point on. Nearly always, a test market will precede initiation of a full national program. A test market is justifiable if: a. More than a "slight risk" is attached to the introduction. b. The test will assist in finalizing certain details of label, advertising, container size, pricing, distribution and so forth. c. By selecting certain test areas, a true indication of the national market can be obtained. d. There are many uncertainties about the product, advertising, distribution, etc. that should be finalized. Presuming that a test market strategy is integrated into the program, typical check points are about as follows: a. Prepare the PERT diagram, or launch timetable. b. Finalize the product formulation. i. Are the color, odor, viscosity and other physical attributes acceptable to consumer panels? ii. Has the product demonstrated compatibility with the least expensive practical container? (At least nine months.) iii. Have all clinical safety tests been completed? iv. Can all label claims be justified to the FTC if necessary? v. Does the product do a highly acceptable job for the intended use? vi. Are all registrations, new drug applications and similar tasks well along or completed? c. Finalize the packaging components. i. Has the package been tested with the formulation? ii. Does the package conform to applicable regulations; such as use of FDA approved materials for foods and drugs, use of child- resistant closures, etc.? iii. Have suitable packaging suppliers been selected? d. Describe the initial brand marketing strategy which will serve as a guide to all future agency actions. e. Write the copy strategy. f. Prepare the label, using "b(iv.)" generalities as a guide. i. Is copy acceptable to the laboratory? ii. Is copy acceptable to legal department? iii. Produce final package art work. g. Prepare the creative material. Test it in panel groups. h. Finalize all market, sales and advertising estimates.
10 The Aerosol Handbook i. Send revised advertising figures to agency for final media budgets. j. Supply accounting, planning, buying, and production with final figures and develop a final overall cost. k. Prepare the final profit statement and make budgetary revisions as needed. 1. Plan for the test market. m. Prepare final media strategy and submit to agency. n. Order all components and chemicals for test market. o. Produce and ship product to designated warehouses. p. Establish final production costs based on experience generated in "o". q. Analyze test market results. r. Revise art, designs, package specifications, formula, etc. as dictated by test market results. s. Establish full national program, t. Plan production on national scale. i. Obtain bids from contract fillers in different locations. ii. Make sure components and chemicals can be produced at needed rates. iii. Consider alternate packaging sources and supplies. iv. Design and produce introductory special displays, etc. u. Consider danger of competition. i. May get into full distribution before you do. ii. May establish deals, price incentives and so forth to eat up available shelf space. iii. May revise copy, advertising methods, even formula to "improved" type. v. Set ad promotional budget. w. Hold national sales meetings and notify trade. i. Distribute salesmen's samples and other selling materials. ii. Inform salesmen about product and strategy. x. Produce and ship product to distribution points. y. Ship to outlets. z. Check consumer purchases in selected stores. It is very important to evaluate continuously the product itself at various stages of development, including systematic consumer testing. Consumer evaluation is necessary to determine what they want from a product, and the value they place on specific attributes. Laboratory evaluations must be meshed into this program, in order to determine how these objectives can best be accomplished. Consumer and laboratory tests can be considered equally important in any development program, since one will rarely provide meaningful answers without the other. Although there is certainly a greater degree of control built into laboratory testing, the procedures are set up usually to test only one attribute at a time. Research people should not be expected to estimate the relative importance of these attributes to the marketing success of the product. In contrast, consumer testing provides a rough estimate of all the factors considered at one time. It is concerned with overall satisfaction or rejection based on subjective factors. Unfortunately, people are often conditioned to expect certain characteristics in a product. One of the pitfalls of consumer testing is that they will fault a product if it does not provide the expected characteristics, even though the attribute may have little or no beneficial effect. (A furniture polish without a lemon odor will probably not sell very well these days, although the citrus fragrance contributes nothing to the polishing effect whatever.) Sometimes the laboratory methods can suffer from over-expertise, since the technical people are well aware of the product and container parameters. In consumer use testing it must be remembered that people do not read "use directions" and do not always use products as intended by the manufacturer. As an example, when a new aerosol valve was introduced, about 1958, a large production of bug killer spray was produced and thoroughly checked by many experts before being released to the market. A week or two later complaints started coming in by the hundreds. The cause? Customers were sometimes tilting the valve during actuation, instead of pressing the button straight down as did the experts. Under this new and unplanned for stress, the gasket allowed secondary sprays of product to spurt out from the base of the stem. Most of the production was recalled, at great expense, and the valve housing fitted with a special press-fitted cap which prevented sideways movements of the stem and button. The design was incorporated into the valve cup a short while later and remains there to this date.
Aerosol Marketing Considerations 11 Other well known limitations of consumer testing are: over-response (people are all too willing to criticize), too short a trial period, as reaction may vary with extended use, lack of specificity, since people tend to generalize, and the possibility that dislike of one product characteristic will be carried over by the consumer to the product's other characteristics. Consumer Profiles A sound marketing program should recognize always the changing market demands for products and services. Demographic surveys show that, while the largest U.S.A. markets are still in the East and Midwest, the greatest percentage gains during the 1980s will be in the sunbelt areas. This will affect package sales of many products, and influence design in favor of stronger colors and more vibrant graphics — a change already noted for outdoor products and those aimed at the large "60-plus" and retiree market. With the huge youth market of the late 1960s and 1970s now blossoming into a booming young adult market of the 1980s some of the current emphasis on teenage needs will subside. During the 1980s there will be a 42 % growth in the number of people aged 35 to 44; both this market and the rapidly increasing market for financially secure older people should cause profound changes in the orientation of many products. In 1960, women accounted for 32.3% of the U.S.A. labor force. This rose to 36.8% in 1970 and to almost 42 % in 1980. This is a significant statistic for marketers since working women have very different buying needs and patterns than the homemaker, particularly in the amount of available discretionary money. They can indulge themselves in items of higher quality if they elect to do so. In 1980, over 55% of all U.S.A. households contained two or fewer people, compared with 46% in 1960; this trend is expected to continue. Also in 1980, single persons made up 30% of the total population, compared with half that level in 1960. With the obvious increase in households, the sale of household products has been advancing at a very fast pace. During the 1980s, an increasing amount of attention will be given to minority needs. In 1980, there were an estimated 25 million Blacks (11 %) in the U.S.A. with a buying power of $96 billion. About 1.0% of this is spent on health and beauty aids. The average Black is 21, in contrast to the White median of 29, and they will account for one-fifth of the population gain during the 1980s. The formal complaints received by marketers represented about one in every fifty significant problems during 1978-79, and was perhaps as high as one in twenty-five in 1980-1981. Other complaint routes involved reports by retail stores regarding returned merchandise and contacts by attorneys seeking restitution for furniture damage and other losses suffered by their clients. Another increasingly important racial group is the Hispanics, with a market of 21 million consumers in 1980. They have a purchasing clout of some $32 billion. Government estimates indicate that by 1985 they will have the largest population of any minority. The median age for the Hispanic consumer is 21.5 years old. With an average household income of $15,000 per year in 1980, they tend to be conservative and family oriented. All these statistics have an important place in any quantitative market analysis. Distribution of income affects the market for many products, and particularly aerosol products. With the "income pyramid" turning upside down during the last 25 years or so, it is essential to recognize family expenditure patterns and predict them into the future. Consumer Attitudes The aerosol package has been extolled as convenient, profitable, clean and soft, easily controlled by the consumer, dependable, easy to use, efficient, having good identity and so forth. These attributes are probably more useful as a palliative to the anxious marketer than as anything highly visible to the consumer. To the buyer, aerosols have been around "forever," always in essentially the same packaging style, and they have little or no novelty. Their advantages are taken for granted; but their presumed or actual disadvantages are treated with less tolerance than ever before. Starting in the 1978-79 period, consumers began to indicate their displeasure with aerosols by means of a significant escalation of written complaints to the marketer. A typical summary of complaints for a shaving cream is shown in Table III. The aerosol package has been increasingly regarded by consumers as a relatively high priced commodity. This is especially the case where the high costs of essentially anhydrous formulations have forced marketers into smaller packages or higher price levels. In 1981, virtually all anhydrous solvent/propellent compositions cost fillers at least $0.30 per pound on a bulk purchase
12 The Aerosol Handbook Table III Aerosol Shaving Cream Summary of Customer Complaints (Third Quarter of 1978 Notation Poor foam consistency Will not release product Pressure problem Will not stop flowing "Dries on Face" Defective valve Particles in Lather Developed rash Can became rusty Bad Odor Clogs Razor Total 1980) Complaint Level 1978 17 18 1 33 0 1 0 0 1 0 0 71 1979 24 24 0 48 1 1 0 1 0 0 1 100 1980 23 28 1 65 1 2 1 0 1 1 2 127 Notes: Approximate sales volume in each period: 3,000,000 units. Complaints for the "brushless" counterpart: 1 in 1978, 4 in 1979 and 12 in 1980 based on sales figures adjusted to aerosol level. The "will not stop flowing" was generally assigned to occasional faulty mis- centering of the lever section of the spout, now corrected by a design change. This problem is readily corrected by the consumer. basis. During the year the list price of the largest tinplate can reached the $0.50 per can level for some variables, as purchased by fillers from canmakers in good volume. The competitive pressures between fillers and in the marketplace during the 1980-81 "stagfla- tionary" period were such that many large-category products were offered in discount stores at very slightly above the marketer's cost; for example, a 1981 sale of three cans of 17-oz. bathroom cleaner, 19-oz. window cleaner or 15-oz. starch was $2.00 total. During the recessionary year of 1980, aerosol sales dropped from a 7% growth rate in 1979 to a -11% growth rate. Similarly, the sale of plastic bottles for chemical specialties went from an 11 % growth rate in 1979 to -7.5%. The spread of each category is about the same, indicating that both suffered the same decline and that aerosol and liquid specialty products were treated the same by the consumer in 1980. The aerosol package is no longer viewed as a virtual necessity by consumers, except perhaps in a few unique areas. During the low point of the recession in May and June of 1980, aerosol productions were down 26% from a year earlier. Some of this was due to forced inventory reduction by some major marketers, and to slow sales and tight money; but it would seem that the consumer can get along rather easily with at least 20% fewer aerosols if he finds more attractive outlets for his disposable income. During the past ten years the sales of aerosol containers to fillers never dipped below about 152 million units in any one month, and some analysts have used this to suggest a minimum or basal trend line to separate normal from deprivation sales levels. Manufacturer's sales of metal and glass aerosols during 1980 are compared with 1979 sales in Figure 1 to illustrate the effect of the recession. Consumer attitudes toward products have changed significantly during the past several years. Buyers have become more pragmatic, seeking products which are economical, efficient and serve real needs. There is a strong interest in personal safety, health and security, as witness the growth in the civilian sales of aerosol stun products of the "Mace" type, which rose from almost zero in the 1970s to a $40 million retail market in 1981. With the very high cost of skilled labor, many consumers have become talented home and car repairmen. As a result, the polyurethane foam insulation aerosol became a $10 million retail item in 1980, and caulking compounds in aerosol form developed the same sales volume in 1982. Automotive aerosols grew by 9.8% in 1979, and increased by almost as much in 1980. Many of these products provide the consumer with energy savings, thus making them doubly attractive. There are certain consumer traits that have encouraged marketers to put their efforts into revitalizing existing products, rather than developing new ones. Figure 1. Aerosol Container Sales in 1980 vs 1979
Aerosol Marketing Considerations 13 Time constraints now often limit shopping time, causing people to buy familiar brands. There is an increasing tendency toward avoidance of risk, perhaps in part due to lurid television and newspaper stories that have made "chemicals", "aerosols" and even "new" bad words; this steers people away from new or untried brands. The public is less attentive, less keyed to new things. Finally, there is continued interest in the genuine original, the authentic tried-and-true, which they may never leave unless some dramatic or emotional issue arises, such as a disappointment or a compelling sale of a competitive product. In general, marketers are far happier to count on continued support of existing products. It is a less expensive, surer way to conduct business. Relatively minor improvements: a new valve, or a revised propellent composition, can be incorporated for as little as $50,000 in research, consumer tests and other routines. The success rate is better than 98%, compared with a recent Benton & Bowles' figure of only 67% for new products unveiled during the 1975-1980 period. Even if the revision fails, the marketer has the obvious option of returning to the original. Many marketers simply feel it is too expensive to launch new products. They keep their customers loyal by extending existing lines or making stronger efforts to lift established brands into new product categories. Special incentives are fast becoming a vital ingredient when a marketer considers a new product possibility. There must be a patent, a uniquely effective formulation, a magic ingredient or some other factor — and even then, many marketers will not stray very far away from fields in which they have strength and expertise. Marketing Strategies Every marketer approaches product introductions or improvements from a different standpoint. There are a few who are interested only in high volume routine products: 5 to 10 million units per year or more. Obviously these are restricted to well recognized and popular items. Others aim for the specialties market, where relatively small sales can still generate interesting profits because of the higher prices that can be charged per unit. Many firms are quite satisfied to capture a very small share of one or more major markets. For instance, it is estimated that there are now about 4800 brands and formulas of aerosol hair sprays. In 1977, and again in 1980, only 19 firms shipped over $100,000 at wholesale prices, but well over 4000 hair sprays had sales volume of a mere several thousand units per year. Many were sold to more than 200,000 beauty salons in the U.S.A. A review of a number of specific aerosol market areas should be of interest in providing information on volume sales, market profile and opportunities that may be available. Shaving Cream This important aerosol category accounted for 93.8% of the $205,000,000 retail market for shaving preparations in 1980. Product use is 94% male oriented and this segment represented 17% of the $970,000,000 retail men's toiletries market for that year. According to Packaged Facts, Inc., the dollar growth of the aerosol shaving cream market went from $181,000,000 in 1979 to $192,000,000 in 1980; from this they predict about a 5% continuing growth to 1986. This is a difficult growth figure to handle, since shaving creams advanced in price from $1.24 (retail supermarket) to $1.38 during 1980, for a gain of 11.4%. Thus a 5 % dollar growth would reflect a sales decline of about 6.4% per year. As a matter of record, unit sale of shaving cream has been increasing at an average rate of 3.8% per year for the 1976-1980 period, and this hardly seems likely to reverse. Explanations could lie in the selection of can size or intensity of price-cutting, but these are hardy sufficient to cover the proposed difference. The market profile in terms of unit volume is given for shaving cream aerosols as follows: s s w S P J O > H Z P 200 180 160 140 120 100 HO 60 40 20 60 62 64 66 68 70 72 74 76 78 YEAR Figure 2. Aerosol Shaving Cream Market Volume
14 The Aerosol Handbook In 1971, a Gillette R&D report stated that 71 % of all U.S. shavers were "wet" shavers and 73% of this group were users of aerosol shaving creams. The average user consumed 26 ounces of aerosol shaving cream per year at an average cost of $0.11 per ounce, thus accounting for a market of $111,000,000 per year. During 1981, a decade later, one can suggest that about 94% of "wet" shavers use aerosol shaving cream; another 5% of sales volume should accrue to increasing use of shaving cream by women. Thus the market should have increased by about 36%. Instead, unit volume was down by 5.0%. This might suggest that circumstances are ripe for a significant regrowth in this product category, and indeed there are many encouraging signs of marketer interest and good sales reports. Rather surprisingly, shaving cream sales are somewhat seasonal: the highest sales develop during August, September and October, when they trend about 10% above average. The lowest sales volume occurs in January, at 12% below average. There are three major formulation types: a. Standard ambient temperature foam. i. Standard formula for men. (Menthol, regular and lemon-lime.) ii. Gentle formula for women. (No sodium or potassium salts present.) iii. Special formula for blacks. (Urea and sodium sulfite usually present.) b. Hot foam. i. Thermogenic or self-heating. (Co- dispensing package with peroxide.) ii. Appliance for external heating. (Electrical or hot-water type.) c. Gelated, post-foaming. i. S.C. Johnson & Son, Inc. "Edge" type. (Patented.) ii. Other varieties, as Carter-Wallace, Inc. type. At least 97 % of the volume is marketed in three-piece tinplate (or C/CO plate) cans. Some high-margin specialty items are sold in two-piece "Spra-tainers" and "Peerasol" aluminum cans in the nominal 6-oz. size. A growing market area has developed recently in the 1 to 1 V% -oz. travel-size package, using an aluminum container. The usual formulation contains about 8% sodium and potassium stearates (80%)/cocoates(20%), 10% triethanolamine stearate(80%)/cocoate(20%) or some mixture of the two. Foam stabilizers such as sodium lauryl sulfate, diglycol stearate, polysorbate 80 and certain amphoterics are then added, along with propylene glycol or glycerin humectants, fragrances and sometimes some special items. In the early 1970s it seemed fashionable to market formulas with as many as 22 ingredients, but later on as many as half were discarded as probably worthless or because they were possible skin sensitizers, or because of the need to report all of them on the label in accordance with a new FDA requirement. The usual propellent selection is a blend of isobutane/ propane or mixed-butanes/propane having a pressure of between 40 to 52 psig at 70°F (276 to 359 kPa-gage at 21.1°C), and being used at about 3.2 to 3.6% of the total formulation. Nitrous oxide, at about 0.9%, has been looked at because it provides dense foams of exceptional surface luster or pearliness. There are some disadvantages of a technical nature, however, such as a growing' 'soupiness'' as the can is emptied, and a more difficult gas injection procedure. Shaving creams typically contain 76 to 79% water and are considered non-flammable under both warehouse storage and consumer use conditions. The freshly dispensed foam can be lit momentarily with a match, but this academic fact has no real significance. The few serious consumer complaints against shaving creams have generally related to the use of steaming hot tap water, poured onto the can for an extended period, with the individual hoping to get a hot shave. In some of these thermal insults the pressure build-up has been so intense as to cause eversion and rupture of the dispenser. While most women use standard men's shaving creams, a number of products are available formulated especially for feminine use. They do not contain the harsh sodium stearate soaps, but tend toward combinations of potassium and triethanolamine soaps, and ideally to the pure triethanolamine (diethanolamine- free) stearate/cocoates, if the expense can be tolerated. This is unimportant for shaving the legs, but mildness is of primary concern when shaving the underarm areas. The hot lathers of the early 1970s are now largely a thing of the past, due to packaging deficiencies and expense. The thermogenic types used combinations of hydrogen peroxide and either sulfite, thiosulfate, thioureas or pyrimidines to react and produce heat.
Aerosol Marketing Considerations 15 The temperature rise could be adjusted by the amounts of thermal ingredients used, and the rate of heating by the use of sodium molybdate or other catalysts. The peroxide was contained in a plastic or laminated bag attached to the valve body, so that upon actuation both it and the product were co-dispensed, mixing and warming up in the process. Problems involved the maintenance of a reasonably close ratio of the two liquid phases during the life of the package. For several products the peroxide concentration exceeded 10% and it was thus capable of permanently opacifying the eye lens, if it were to be "spritzed out" as the last bit in the can and somehow contacted the eye. Nearly all the co- dispensing valves were sensitive to throttling actions by the cautious consumer, losing their ability to maintain the correct ratio of phases when this happened. Other difficulties involved production of slightly malodorous reaction by-products, plus the production expense of having to fill separately polyethylene tubes in a special filler, join them to the valve, and then hand-insert the special valve into the aerosol can. During the 1967-1973 period a significant number of thermal products were marketed. "The Hot One", "Rise-Hot" and "Hot Lather" captured an estimated 6.5% of the total shaving cream business, with retail sales of about $6.7 million. Other products included hot windshield de-icers, hot beauty oils, hot facial cleaner foam and an experimental hot pre-surgical scrub. These products have nearly vanished today, and the business climate does not seem propitious for their return. Shaving cream cans may be fitted with an appliance for achieving a hot foam. The earliest one (circa. 1963) consisted of a vaned metal chamber, preheated by passing hot water over the exterior, after which the shaving cream was forced through the device so that it emerged in a moderately warm condition. Since then, a large number of hot water heaters have come and gone, with an indifferent response in the marketplace. One shortcoming is that most of them are limited to use with just one aerosol valve design. A more effective but vastly more expensive appliance is the electrical type. The can is often fitted inside this heater, and used routinely until it is empty. The unit is plugged in and activated, with an amber light coming on when the heating step is complete. The formulas for these units are best made with thickeners, such as gels and cetyl alcohol, so that they will not be too loose when heated to 180°F (82°C) or higher. Also, the ingredients must be thermally stable at such temperatures, without changing color, texture or fragrance. Although heating to such high temperatures may seem excessive, actually it is not; the foam structure has such a low thermal transfer rate that it can be placed on the skin at literally 212°F (100°C) without discomfort — provided it remains a stable foam, without weeping. The "Hot Lather Machine'' is the most popular of the electrical types, although sales are slowly declining. The device will accept only the 6-oz "Schick Hot Lather" "Spra- tainer" can, fitted with a long-stemmed aerosol valve. About 1966, S.C. Johnson & Son, Inc. brought out their "Edge" shaving cream, and with it a new dimension to the aerosol shaving lather business. Packaged as a light green gel in a "Sepro" can, the product contained a dispersed P-114/pentane propellent (now isopentane) which became gaseous when the gel was rubbed across warm skin, causing the appearance of a foam structure. The novelty and heavy advertising brought the product up to an 8.4% market share in 1970, after which something of a sales slump took place. An improved formula with superior lubricity was then developed and promoted in the media as "To cut yourself you almost have to try!'' The lubricity resulted from the use of certain diethanolamides and other special ingredients. By 1977, the product had slowly captured a 13.5% market share, and by 1981 this reached about 16%. At this time it was emulated by products in "Sepro" cans marketed by Carter-Wallace, Inc., makers of "Rise" shaving cream, the overall brand leader for many years. It is hard to predict the future of these unusual shaving creams, but it seems likely they will carve out even larger market shares in the forthcoming years. Other innovations in the shaving cream market have included a formula with "all natural" ingredients, one designed to actively inhibit the corrosion of razor blades and one based entirely upon non-ionic detergents. During 1981, Jasco Products, Inc. introduced "Brush-On", an actuator fitment ending in a large brush of imported boar's bristles. The first shaving creams to use designer perfumes were test marketed in 1980, with "Burley" and "Aramis" fragrances, breaking away from the traditional, nondescript, menthol and lemon-lime types. Still further marketing ploys include the use of shaving cream as one of a number of men's toiletries in lines with highly similar labels, such as the "Yardley of London Spice'' grouping. All in all, the aerosol shaving cream market looks healthy and certainly capable of significant additional growth.
16 The Aerosol Handbook ' 900 800 — 700 s s ~~ 600 u 2 o > 400 H Z P 300 200 60 62 64 68 70 72 74 76 78 80 TEAR Figure 3. Aerosol Hair Spray Market Volume Hair Sprays Hair spray is one of the most fascinating of all the aerosol markets. At one time it was the acknowledged leading category, with sales of 548 million units in 1969, some 22.2% of the total U.S.A. volume in that year. But with the onslaught of the CFC environmental problem, changes in hair styles, the growth of pump-spray alternatives and so forth, sales dwindled to a mere 255 million units in 1980, only about 12.0% of the volume of sales of all aerosols. The unit sales profile of aerosol hair sprays is shown in Figure 3. The phenominal decline in the market share of the aerosol form can be shown by a review of published Towne-Oller data during the CFC/ozone reactionary period, when millions of consumers forsook the product in favor of the pump-spray, as shown in Table IV. This and confirming data by the A.C. Nielsen Co. show that the aerosol market stabilized at about Table IV Unit Market Shares of the Aerosol Hair Spray Year 1974 1975 1976 1977 1978 1979 1980 Quarter Aerosol Market Share (Per Cent) 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 97 97 96 94 91 89 86 83 81 79 80 75 73 72 70 69 67 65 66 65 64 63 63 63 63 61 62 62 Table V Unit Hair Spray Market in England; 1972 - 1980 Year Unit Sale (Millions) Population (Millions) Units Per Capita 1972 1973 1974 1975 1976 1977 1978 1979 1980 117 133 146 132 139 123 127 104* 98 55.80 55.93 56.05 55.96 55.94 55.90 55.87 55.93 55.98 2.10 2.38 2.61 2.36 2.48 2.20 2.27 1.86' 1.75 'The apparent decrease is explained in that, from 1978 to 1979 total aerosol production decreased 7.4% (to 522,000,000 units) and manufacturers increased can sizes from 120gto200g. Aerosols held 91.4% of market in 1979. Table VI Unit Hair Spray Market in Japan; 1972 - 1980 Year 1972 1973 1974 1975 1976 1977 1978 1979 1980 Unit Sale of Hair Spray (Millions) 57 63 55 57 62 53 51 52 53 Unit Sale of All Aerosols (Millions) 207 243 230 220 252 269 301 341 311 Per Cent Hair Spray 27.5 25.9 23.9 25.9 24.6 19.7 16.9 15.2 17.0 Units Per Capita 0.54 0.59 0.50 0.52 0.55 0.47 0.44 0.45 0.46
Aerosol Marketing Considerations 17 Table VII Total Unit Hair Spray Market in The U.S.A. (Expressed as number of aerosol hair spray can equivalents; 1973 1980.) Year 1973 1974 1975 1976 1977 1978 1979 1980 Aerosols 97 96 87 79 71 66 63 62 Market Share (Per Cent) Pump Sprays 3 4 13 19 28 33 36 37 Other (as dips) 0 0 0 0 1 1 1 1 Actual Units Aerosols 453 376 308 285 223 224 238 252 (MM) Pumps (etc.) 14 16 44 76 89 115 140 154 Equivalent Units Aerosol Aerosols Equiv. * 453 376 308 285 223 224 238 252 + + + + + + + + 25 29 79 137 160 207 252 277 ;(MM) Total = 478 = 405 = 387 = 422 = 383 = 431 = 490 = 529 'Expressed as the actual number of pump-sprays, dips and other non-aerosols, multiplied by a factor of 1.8. 63 ± 1 % during 1979 and 1980, after losing some 34% to the pump-spray packaging form. During this period the pump-sprays were advertised at greater than ten times the expenditure for the aerosol form, and virtually every marketer promoted the aerosol merely as an "also ran", if at all. An interesting comparison can be made in the case of the aerosol hair spray market in England, where the chlorofluorocarbon/ozone theory never achieved much publicity until about 1979 (Table V). A second comparison can be made with the aerosol hair spray market in Japan, a case in which the total aerosol consumption rose rapidly during the 1972-1980 period (Table VI). Data in the U.S.A. and England show that women use aerosol hair sprays at 7.5 ±2.5 g per application and men use them at 4.0+0.9 g. In the case of domestic pump-sprays, the use rate by women is 3.2 +0.7 g per application. The ranges represent the difference between light and heavy users. The comparison between female users of both product types is not surprising, since the pump-sprays contain an average of about 1.9 times as much film-forming resin as the aerosol hair spray, the usual ranges are about 3.4 to 7.0% vs. 1.2 to 2.8%, respectively. These data can be adjusted to consider relative dispenser size and used to develop a tabulation of total hair spray usage, based upon "aerosol hair spray can equivalents", as shown in Table VII. The total column in Table VII shows the number of aerosol hair sprays that would be used in the absence of other packaging forms. The production dip in the 1974-1978 period is probably due mainly to an overall consumer reaction against all forms of hair spray, due to the ozone controversy. The increases following 1978 may be attributed to the increased numbers of women entering the work force, different hair styles and a dulling of consumer recollections regarding the controversy. Nearly one-third of all young girls (about 4,000,000 in the age 12 to 18 category) used hair spray in 1979, twice as frequently as in 1976. During 1979 and 1980 there was an increasing trend toward the extra-soft, soft, and gentle hold hair sprays, as well as an increase in the hard-to-hold and extra firm types, all at the expense of the regular category. The soft holding sprays were positioned toward the fast- growing teen-age market, while the growing market of older people increasingly preferred the firm holding formulas to prevent fly-away hair. The overall market profile in 1980 is shown in Table VIII. Use of hair sprays exhibits very little seasonality; sales in the months of March and April are about 5 % above average, with the other ten months not varying Table VIII U.S.A. Hair Spray Market Profile - 1980 Product Type Pump Spray Regular Hard-to-Hold Super Hard-to-Hold Aerosol Spray Extra Soft Soft Regular Hard-to-Hold Super Hard-to-Hold All Others (as dips) Share of Category (Per Cent) 25.5 4.6 7.0 0.8 3.1 23.1 15.3 19.7 0.9 Resin* (Per Cent) 3.8 7.0 8.2 1.2 1.6 2.0 2.3 2.6 (Diverse.) "Will vary somewhat according to type of resin used.
18 The Aerosol Handbook more than about ±3% from the average. "Final Net" is the leading non-aerosol hair spray, and in fact leads the entire category in dollars. The leading aerosol product is "AquaNet" followed closely by "VO-5", "Miss Breck" and the five Toni Division-Gillette products, such as "Adorn" and "White Rain". "Rave", introduced in 1979 to cater to the teen-age soft-hold market, has made surprising gains and was followed in 1980 by "Adorn Soft Hold" and others. The current problem with soft-hold sprays is that while they promise hold, over 33 to 63% of the users (depending on the product) find that the level is unsatisfactory. In 1980, a typical 10-oz. hair spray could be purchased at discount center sales for as low as $0.79, and this price advanced 8.5% during the following year. For comparison, the cost of a typical 10-oz. non-aerosol hair spray on the same basis was $1.09 in 1980 and $1.18 in 1981. The Marketing Focus newsletter reported the total hair spray market as $352,000,000 for 1980. Despite the fluorocarbon/ozone controversy, the recession, and other factors, the dollar volume of hair sprays has advanced each year for at least the last ten years. Formulation of aerosol hair sprays is an interesting subject. During the early 1970s, nearly all U.S.A. products contained about 45 to 50% of a propellent blend averaging about 55% P-ll, 35% P-12 and 10% A-31 (isobutane). The rest was anhydrous ethanol plus resins, neutralizer and perfume, except that sometimes up to about 10% methylene chloride was added to reduce cost, enhance resin solubility, and lower relative flammability. After the fluorocarbon/ozone controversy, products were pressurized with hydrocarbon propellents, typically A-31, A-40, and A-46, all used in the 20 to 25% range. (Carbon dioxide was tried, at 5% or so, but the product was always delivered with too much force due to the 100 psig initial pressure at 70° F and the inability of the limited amount of propellent to adequately break up the spray. These formulas were abandoned after about two years; e.g., 1979.) Because the apolar hydrocarbons limited the solubility of most resins in the ethanol/propellent system, many marketers added modest levels of methylene chloride to prevent the resins from separating at storage temperatures below about 55°F. The usual levels were 8 to 21 % of the total formula. The addition of water was found to accomplish the same purpose, and more cheaply, although not more than about 10% could be added without incurring phase separation. Other problems involved can corrosion and changes in the drying ratio. In general, can corrosion could be controlled by using an amine based resin neutralizer in conjunction with extremely pure water and a double lined can, preferably one with an' 'Organosol'' dome lining. The drying ratio problem, a measure of the distortion of the set- Table IX Unit Shares of Major Hair Spray Brands in the U.S.A. Marketer Brand Name Unit Share of Category (%) 1971 1981 1981 All Outlets All Outlets Food Stores Clairol Division Shulton Division Chesebrough-Ponds Alberto-Culver Gillette (Toni Div.) Rayette- Faberge Whitehall Lab's. Others Final-Net* Miss Breck, etc. Rave VO-5, etc. White Rain" Mink Difference*** Adorn Aqua-Net** Caryl Richards Sudden Beauty 2 10 0 5 7 0 7 19 6 6 38 15 10 9 7 7.8 2 6.5 5 1 1 36 12 12 19 •"Introduced Sept. 1981 * Pump-action spray. (Introduced as aerosol spray in 1982.) * * Lower cost entries.
Aerosol Marketing Considerations 19 fixed coiffure upon application the spray, assumed minor importance at the 5% water level, and was still quite modest at 8 to 10%. Around 1976, La Maur, Inc. introduced a hydrocarbon version of their "Style" and other professional use hair sprays. A211 x 713 can was used, labeled 20 fl. oz. (16 av.oz. or 1 lb.). In order to fit both label declarations, and also into the can, the company used methylene chloride at about 18% of the total formula to gain the needed increase in product density. Other marketers of institutional hair sprays, such as Faberge, Inc. and Bonat, Inc., were quick to follow, setting a labeling trend for these hair sprays that remained strong in 1981. In the quest for reduced flammability, several marketers are now experimenting with hair sprays based on the use of dimethylether (DME). This propellent was produced only in Japan and Europe, but it is now also made by E.I. Du Pont de Nemours & Co., Inc. (for non-captive uses) in 1982, and by Conn Chem Div. Canada in 1983. A major impediment is the current U.S.A. price of about $0.57/lb. (1982), which is only slightly less than the imported cost of bulk "tank- tainers'' of DME from Germany. This is about three times the price of most hydrocarbon blends and well above the European price of about $0.25/lb. Data are given in Table X showing proposed formulations in both the U.S.A. and Europe, where DME functions as the primary propellent. The use of so much water in the proposed U.S.A. formula does not contribute as much toward the relaxation of waved hair as might be imagined. Droop is minimized by the azeotropic removal of much of the water by the dissolved DME. There still remains a problem with product cost, but this is partly compensated by the much reduced flammability level of the product. The selection of film-forming resin is critical for hair sprays and sets. Some require plasticizers and others do not. The original aerosol hair spray was '' Liquinet'', in 1948, which used shellac. In 1950 PVP (polyvinylpyrrolidone) was found to be a better choice, but it had low curl resistance to high humidity droop. During the early 1950s, copolymers such as P(VP/VA) 70:30 were introduced by GAF Corp., in which the vinyl acetate part acted to reduce sensitivity to humidity and improved holding power. Further improvements came in the 1960s, when National Starch & Chemical Corp. developed "Resyn 28-1310," a vinyl acetate/crotonic resin, to be followed by GAF Corp.'s "Gantrez ES-225", monoethyl ester of polyvinylmaleate/maleic anhydride copolymer, and "Gantrez ES-425", the slightly less polar monobutyl ester. Still later National Starch & Chemical Corp. brought out the first public offering of a terpolymer, with their "Resyn 28-2930" (vinyl acetate/crotonic acid/vinyl neodecanoate polymer) and "Amphomer" (an octyl acrylamide/arcyl- ates/butylaminothylmethacrylate polymer). The state of the art rested at this point until 1980, when Stepan Chemical Co. introduced its "Stepanhold R-l" terpolymer resin, and 1981, when the Amerchol Corp. began offering "Amphoset" terpolymer, equivalent to the leading hair spray resin of Japan. The resins must give adequate hold, even in high humidity conditions, but they must also provide high lustre, easy comb-out, minimum stiffening or boardi- ness, no flaking, no yellowing or darkening, and be removed readily by shampooing in warm water. Add- Table X Hair Spray Formulations Using Dimethyl Ether Ingredients Fixative Resin* Neutralizer Perfume, etc. Ethanol (anhydrous) Isopropanol** Methylene Chloride De-ionized Water P-ll (CCUF) P-113(CC12F.CC1F2) Dimethylether U.S.A. 3.0 0.1 0.1 31.8 — — 30.0 — — 35.0 England 3.0 — 0.1 15.0 — 15.0 — 36.8 — 30.0 France 3.0 — 0.1 5.0 — — — 66.9 — 25.0 France 3.0 — 0.1 5.0 — — — 51.9 40.0 Germany 3.0 0.1 0.1 3.0 7.0 35.0 — 26.9 — 25.0 Germany 3.0 — 0.1 3.0 7.0 35.0 — 16.8 35.0 Italy 3.0 — 0.1 5.0 — 35.0 — 31.9 — 25.0 'Indicated on a 100% solids basis, although some are marketed as the 50% solution in ethanol and in similar forms. **Used because of government taxes on ethanol.
20 The Aerosol Handbook ing plasticizers will partly neutralize and soften most resins, rendering them more water dispersible and more polar in their solubility relationships. Excess use of plasticizers will cause tackiness (reduction of coherent bonding) and flakiness (reduction of adherent bonding). The hair will also pick up dirt faster. Certain plasticizers may migrate to the surface of the film and cause changes in "tackifier" properties. This can be an important factor when the plasticizer ratio is high, as in certain "soft-feel/good-hold" formulas using "Gan- trez" resins, where the plasticizer is increased from the usual 12% (of the resin level) to 18 to 20%. One major formula avoids higher plasticizer problems by using a Resyn neutralized with AMP at 7.5%; another uses "Stepanhold R-l", which does not require an external plasticizer. There are a number of aerosol hair products. The hair set is a strong-hold formula, designed for application after shampooing and conditioning. Various hair sheens are available which seem to be particularly popular with Blacks, based upon myristyl lactate lauryl laurate and similar hair substantive ingredients that adhere to the hair and give it shine and substance. Hair sprays with built-in conditioning action have been developed recently, using the GAF Corp.'s "Gafquat 755N" polymer. In fact, the combination of "Gafquat 755N" and copolymer "8-45" is useful for soft-hold, conditioning type hair sprays. 1,000 900 800 60 62 64 66 68 70 72 74 76 78 YEAR Figure 4. Aerosol Antiperspirant/Deodorant Market Antiperspirant Sprays Of all the major aerosol categories, the antiperspirant spray was the one affected most severely by the impact of the fluorocarbon/ozone controversy on marketer activities and consumer buying practices. (The colognes/perfumes and frypan lubricant sprays were stricken even more, but were not major product lines.) There are two distinctly different types of underarm sprays: the antiperspirant, which controls both wetness and odor, and the personal deodorant, which minimizes odor by germicidal action. The antiperspirant always contains aluminum chlorhydroxide powder, suspended temporarily by shaking in a solution of predominantly hydrocarbon propellent. It must reduce underarm sweat levels by at least 20%, averaged across a one day period, in order to be legally called an antiperspirant. If the product is declared to be an extra- strength antiperspirant, then it must produce at least a 30% reduction. The aluminum chlorhydrate complex first acts to reduce perspiration by dissolving in the ever-present film of underarm moisture, forming an astringent, mildly acidic salt solution that closes the axillary sweat pores to varying degress. Meanwhile, the acidic solution (pH = 4.0 ± 0.5 as a rule) causes bacteriostasis, so that the resident skin bacteria which catabolically produce the characteristic underarm odors are unable to function. In the past, a few marketers added germicides to antiperspirants, but this approach has been found superfluous and is no longer done. As a general rule, the aerosol underarm products run about 80% antiperspirants and 20% personal deodorants in unit volume. The deodorant came first, being developed about 1957, and it represented a new application for a simple ethanol/fluorocarbon type formulation. When the more complex antiperspirant came along two years later ("Princess Val", developed by Don Virzi at Chase Products Co.) it caught hold rather quickly, pushed past the deodorant and ran ahead to achieve a unit volume estimated at some 480,000,000 units in 1974. This same situation is now being experienced in the young and fast-growing stick market, where personal deodorants held 60% in 1980 but less than 50% in 1981, as antiperspirants took the lead. Underarm aerosol products are often lumped together as deodorants, or as antiperspirants in marketing reports and other non-technical literature. The SAMI (Selling Areas Marketing, Inc.), Nielsen (A.C. Nielsen Co.), CSA1A and other market surveys all consider these two products as one category, and no
Aerosol Marketing Considerations 21 further breakdowns are given. On the other hand, some published Towne-Oller reports do quantify the component product sales figures. The unit sales profile of the aerosol antiperspirant and personal deodorant products is shown in Figure 4. The dramatic decline in the market share of the aerosol antiperspirant/deodorant spray can be illustrated by Table XI. These and other data show that the aerosol form has lost a 52% market share during the seven year period of 1974-1981. The burgeoning sales of the antiperspirant stick, scheduled to increase strongly during 1981, with three large marketers set to launch these products, shows that the slide of the aerosol forms is still continuing. Aerosols will be surpassed by roll-ons during 1981, and both of these will be overtaken by the stick form by 1983-1985. Marketers have several concerns with antiperspirant aerosols. In order to get the benefit of about a quarter ounce of aluminum chlorhydrate the consumer must purchase a relatively expensive can, as well as a large amount of hydrocarbon propellent. The propellent averages about 70% of the formula. The can may contain a half ounce of alluminum salt, but only about 55% is actually transferred to the underarm area; the rest is lost to the air during spraying and the potential long- term toxicological effects of breathing this dust is the subject of intensive study by both the FDA and several marketers. In the old fluorocarbon antiperspirants the transference efficiency averaged about 86%. Although Table XI Unit Market Shares of Antiperspirants and Deodorants - All Types Year 1974 1 2 3 4 1975 1 2 3 4 1976 1 2 3 4 1977 1 2 3 4 1978 1 2 3 4 1979 1 2 3 4 1980 1 2 3 4 A.P. 60 55 54 54 51 48 45 41 40 38 36 32 33 34 33 33 33 31 31 29 29 28 27 25 24 24 Aerosol Products P.Deod. 15 16 16 16 16 18 18 18 18 16 14 12 13 13 13 12 13 12 12 12 12 11 11 11 11 10 Powder A.P. 13 12 12 11 9 8 7 6 6 6 6 5 5 5 5 5 4 4 4 4 4 4 4 4 4 4 Total Aerosol 90 89 88 83 82 81 76 74 70 65 62 60 56 49 51 52 51 50 50 47 47 45 45 43 42 40 39 38 A.P. Roll-On 4 5 6 10 12 11 16 16 18 19 20 22 26 30 27 27 28 29 29 32 32 34 34 34 35 35 AP&PD Sticks 1 1 2 2 2 3 3 4 5 7 7 8 9 10 10 10 10 12 12 13 13 14 14 16 18 20* Non-Aerosol Products A.P. Creams 4 4 4 4 4 4 4 4 4 4 3 4 4 4 3 4 4 4 4 4 4 4 4 4 3 3 A.P. Pumps 0 0 0 0 0 0 0 1 2 4 5 5 4 7 8 7 7 5 5 4 4 3 3 3 3 2 Pads& Sq. Bottles 0 0 0 0 0 0 0 0 0 0 0 0 *Gillette claims the total stick solid segment increased from a 19.1% unit share in 1980 to a 23.5% unit share in 1981. Of the total segment, antiperspirant stick solids went from a 6.9% unit share in 1980 to a 10.5% unit share in 1981.
22 The Aerosol Handbook the technology for doing almost this well with hydrocarbon formulas is available, it has yet to be applied commercially. The alternative packaging forms generally contain more active ingredients than the aerosol, as shown in Table XII. Table XII Level of Antiperspirant Salt in Various Product Forms Percentage of Aluminum Chlorhydrate Product Type Average Range Aerosol Standard Formulas Water-Based Formulas Light Powder Formulas Roll-On Stick Cream or Lotion Pump Pad Squeeze Bottle 11 17 5 20 21 15 16 25 9 5 to 14 15 to 21 4 to 7 18 to 23 18 to 25 12 to 16 12 to 20 25 6 to 12 Except for the pad (which has a negligible market share) they deliver practically all of their astringent salt to the underarm area during normal use. In some instances they use antiperspirants that are more biologically active than those permitted for use in aerosols, e.g. aluminum zirconium tetrachlorohydrex-glycine. Despite the concerns about economics, toxicology and relative efficacy, the aerosol antiperspirant remains an exceptionally easy, quick, clean and decisive way to treat the underarm area. There is no stickiness; no sensation of "something" having been laid down on the skin. The aerosol is also versatile to the extent that more can readily be sprayed on, perhaps to compensate for a hot day, exercise or other activities. One aerosol can may be used hygienically by the whole family. To compensate for this, the roll-ons and sticks have now been positioned as personal (not family) products. An interesting comparison can be made between the antiperspirant market in the U.S.A. and in England, where the chlorofluorocarbon/ozone issue did not receive much publicity until about 1979, and where nearly all antiperspirants are still formulated with chlorofluorocarbon propellents. In mid-1980, the aerosol sector of the total English market accounted for 64%, compared with 40% in the U.S.A. The roll-on is the major alternate. In England, stick antiperspirants suffered from severe dry-out and weight-loss problems, which were solved in 1979. But this factor acted to depress the category strongly until then. The antiperspirant aerosol market was about $92,000,000 in England during 1980, and in that year the brand leader, Elida Gibbs (Sure), with about a 19% share, spent about $1,900,000 in heavily TV-weighted advertising. Such advertising commitments are totally missing from the U.S.A. market. The antiperspirant aerosol market in England is shown in Table XIII: In mainland Europe, the popularity of the underarm aerosol products has been maintained all through the 1970s, but with a distinct shift toward the deodorant- cologne side of the market. Rather interestingly, this perfume-enhanced deodorant was not available in the U. S. A., until 1982, but it comprises by far the strongest sales in West Germany and to a lesser extent in Switzerland. The popularity of this item may explain why the 1979 per capita use of underarm aerosols was 2.09 in West Germany, but only 1.25 in the U.S.A. The second largest per capita use of underarm aerosols in Europe was in Switzerland, at 1.80. A final comparison can be made with the aerosol antiperspirant/deodorant market in Japan, where total aerosol consumption increased rapidly during the 1970-1979 period. This is given in Table XIV. Unit sales increased every year of the decade. They advanced from a factor equal to 4.0% of hair spray sales in 1970 to 33.5% in 1979, and still increasing in 1981. Data developed in the U.S.A. and England show that hydrocarbon-based antiperspirants and deodorants are used at about 1.9 g per application, whereas the Table XIII Unit Antiperspirant/Deodorant Aerosol Market in England; 1972 - 1980 Year 1972 1973 1974 1975 1976 1977 1978 1979 1980 Unit Sale* (Millions) 48 62 70 51 59 61 45** 53** 61*** Population (Millions) 55.80 55.93 56.05 55.96 55.94 55.90 55.87 55.93 55.98 Units Per Capita 0.86 1.10 1.25 0.91 1.05 1.09 0.81 0.94 1.08 'Figures do not include feminine hygiene sprays and food deodorants, two categories often lumped into European surveys of antiperspirants and deodorants. **The decrease is due mainly to competition from roll-ons on economic grounds. **'Unexplained sales surge in all forms of antiperspirants and deodorants.
Aerosol Marketing Considerations 23 Table XIV Unit Antiperspirant/Deodorant Aerosol Market in Japan; 1970 - 1980 Year 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 A.P. Deod (MM) 2.1 2.6 4.4 4.4 8.7 9.0 11.5 12.6 17.9 19.1 22.0 All Aerosols (MM) 174 191 207 243 230 220 252 269 301 342 311 A.P./Deod. 1.21 1.36 2.13 1.81 3.78 4.10 4.56 4.68 5.95 5.58 7.07 Per Capil 0.020 0.025 0.042 0.041 0.079 0.082 0.102 0.111 0.156 0.164 0.190 fluorocarbon counterparts are used at 3.6 g. Some of these products contain mixtures, such as those with about 25% isobutane as the true propellent, and 60% P-ll as the solvent/carrier component. (These are also popular in Australia and in Canada, where they are sometimes referred to as "the Gillette formula".) Figures on amount per application vary, but about 3.0 g is probably a good average. In sharp contrast, the average application rate for roll-ons runs about 0.63 g while sticks are about 0.58 g. These low usage levels explain the rather small package size of these alternate formulations. Using the 1979 retail prices, a cost effectiveness study shows that aerosols average about 1.8 times the application cost of the other two types, although formula types, product sizes and other factors have led to the development of a surprisingly large cost of application range for all three packaging forms. This economic disadvantage does not bode well for the aerosol, despite its many advantages as a delivery system. Formulation of antiperspirants is a complex subject. Almost without exception they contain about 12% aluminum chlorhydrate complex (shortened to aluminum chlorhydrex for labeling purposes), having the formula [Al2Clx(OH)6.x]n, where x = about 1.0 to 1.6 and n is a very large number. As the amount of CI (chloride) increases, efficacy rises, but problems of dermal and nasal irritation may also increase, especially in the case of sensitive people, typically the older, overweight woman who shaves the underarm area. About 0.06 g of aluminum salt (for women) is required per underarm to produce sweat reductions comfortably above the 20% minimum FDA requirement. For men, this escalates to about 0.08 g, simply due to scale up. A two-second spray time under each arm is stipulated in the FDA test protocol; using this it follows that the spray can must deliver 0.03 g/s (for women) or 0.04 g/s (for men) to the underarm surface. Considering the more rigorous case which applies to men, and assuming the transfer efficiency of the hydrocarbon-based aerosol spray is only 60%, then 0.067 g/s at 70°F (21.1°C) of aluminum salt must be sprayed to achieve the desired result. Valve delivery rates will vary depending upon selection, and the delivery rate will also fall off somewhat near the end of the can, since a vapor-tap valve is required for a relatively slow spray rate, while still using large enough valve orifices so that they will not become plugged by the powdered product. A spray rate of about 0.55 g/s at 70°F (21.1°C) is considered a practical minimum. From this the percentage of aluminum salt can be calculated from the expression: In practice, a 12.2% aerosol antiperspirant will give about a 28% average level of sweat reduction for a panel of equal numbers of men and women. For men, as a sub-group, the estimate would be 24.5%, and for women about 32.2%. Around the half-full area, the level of antiperspirancy will rise a few points, due to the progressive depletion of propellent and increase in transference index, counterbalanced only slightly by a decrease in delivery rate. And at the point of near emptiness, antiperspirancy will dwindle a few points, due principally to the decrease in delivery rate. Lest these figures appear to give an overly precise picture of the relationship of sweat reduction to aluminum salt level, it is appropriate to say that this is far from the case. Variations of 20% or more are not uncommon. In fact, experimental formulations have sometimes been found to include antiperspirant blocking ingredients that cause surprising reductions below anticipated efficacy. The particle size of the aluminum chlorhydrate is extremely important from both a toxicological and valve operation standpoint. As a general rule, particles Spray rate of aluminum salt (g/s at 70 °F) (21.1 °C) n nc- -^-J! __ - vs t\ > = 0.067 x ioo% = 12.2% Aluminum Salt Spray rate of aerosol can (g/s at 70 °r) (21.1 ^J) n ,-,-
24 The Aerosol Handbook with a mean diameter of about 0.5 to 6.0 microns stand a good chance of being retained in the deep, sub-cilial alveolae of the lung if inhaled. Those above about 6 microns will impact in the cilial region and be removed from the lungs by automatic body functions. Because of this, the makers of aluminum clorhydrate have made the product available in a "macrospherical" form, where about 99.7% of the material is present in the form of roundels having a mean diameter of at least 6 microns. The upper particle size range of a typical product: "Macrospherical 95F" is about 55 microns (0.002 "), and this has been shown to still be compatible with valve systems of the powder-tolerant type — although not by a particularly large margin. A more detailed discussion of the toxicological aspects is given in the chapter on toxicology. Personal deodorants are relatively simple formulations. Typically they consist of about 30% hydrocarbon propellent, such as A-70, about 68% anhydrous ethanol, and small amounts of benzthionium chloride or other germicidal agents. One firm uses three related parabens. Perfume is included at up to about 1 %, and a bit of glycol, isopropyl myristate/palmitate or other oily vehicle is put in to help cause the germicide to adhere to the skin while providing a lubricious film. Nearly all antiperspirants and deodorants are sold in 202-diameter cans, up to the 509 height. The outlet breakdown was 51.2% in food stores, 31.0% in drug stores, and 17.8% mass merchandising stores during 1980. The heaviest advertiser was Procter & Gamble Co., with about a 16% share; they were probably also the market leader for that year. The brand share of major products within the three aerosol spray sub-categories is shown for the years 1977 and 1978 in Table XV. During these years the leading marketer was Procter & Gamble Co., with a 32-35% market share, and the leading single product was "Right Guard", available in roughly 65 items. The greatest loser in the period was "Arm & Hammer", with a -92% change. Perfumes and Colognes This dual category is interesting in that it was the hardest hit of all aerosol areas by the CFC/ozone problem, decreasing from 169 million to a mere 11 million units in the U.S.A. in four years. In contrast, sales in other countries were virtually unaffected. The unit sales profile of perfumes and colognes is shown in Figure 5. The U.S.A. is the largest consumer of fragrance products in the world, yet the rate of use of aerosol perfumes and colognes is less than that of England, West Germany, Saudi Arabia and several other countries. Also in the U.S.A. the men's fragrance market is well developed and grew 1.9 times the rate of the women's component during 1980 and 1981. Despite this, aerosol fragrances for men are virtually unknown. A comparison between the U.S.A., English and Japanese aerosol markets is given in Table XVI. Table XV Dollar Volume Brand Share of Major Antiperspirant/Deodorant Aerosol Products; 1977 - 1978 Brand Name Sure Secret Right Guard Soft 'n Dri Arrid Dial'* Ultraban Dry Ban Brut Old Spice Mennen Arm & Hammer Others Total: Deod. 0 5.16 12.80 0 0.04 Negl. 0 0 1.80 0.86 0.78 2.61 1.05 25.10 1978 (Per Cent) A.P. 20.12 6.62 7.32 5.76 12.00 5.70 4.62 Negl. 2.16 0.2 Negl. 0 0.99 65.21 A.P.P.* 0 0 2.50 0.97 5.29 Negl. 0.04 0 0.45 0 0 0 0.41 9.66 Total 20.1 11.8 22.6 6.7 17.3 5.7 4.7 Negl. 4.4 0.9 0.8 2.6 1.5 100.0 Deod. 0 5.90 14.63 0 0.02 Negl. 0 0 2.25 1.12 0.90 0.20 0.47 25.39 1978 (Per Cent) A.P. 21.34 7.86 5.95 6.41 12.48 5.37 3.24 Negl. 2.36 Negl. Negl. 0 0.76 65.39 A.P.P. 0 0 2.40 1.17 4.74 Negl. 0.02 0 0.33 0 0 0 0.15 8.81 Total 21.3 13.8 23.0 7.6 17.2 5.4 3.3 Negl. 4.9 1.1 0.9 0.2 1.3 100.0 *Antiperspirant powder sprays. These products typically contain 2.0% talcum powder. **Includes Dial Very Dry.
Aerosol Marketing Considerations 25 Table XVI Unit Volume of Aerosol Perfumes and Colognes in the U.S.A. and Japan, 1970 - 1979 Millions of Units Year 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 U.S.A. 90 96 158 169 134 80 63 11 24 29 30*** England 46.3 51.0* 57.3 64.6 59.8 64.5** 51.0 Japan 2.6 2.5 2.1 3.3 1.6 1.2 0.7 1.7 1.3 1.2 0.5 *48% of the total $84 million market. **40% of the total $88 million market. ***With 43% in aluminum tubes, up from 29.3 i 1978. In the U.S.A., as aerosols rapidly lost market share starting about Oct. 1973, marketers began to realize the implications of the CFC/ozone controversy. Eventually they might have to use flammable hydrocarbon propellents, where odor was somewhat variable and where certain low-level impurities (as isobutylene, 1,3-budatiene and acetylene) could damage sensitive fragrance components. Other problems soon surfaced. The usual fluorocarbon type perfumes and colognes were formulated completely by the filler, including propellent, and allowed to remain in a loosely closed tank at about 20°F (-7°C) until the incompatible resins and substantives finally precipitated and could be filtered out. The resulting clear product was cold-filled into tubes or bottles, which were then sealed by clinching the valve in place. Because of the problem of flammability, this method could not be used when a switch to hydrocarbon propellents was forced by the government ban on use of fluorocarbons. Fillers would have to add a filtered concentrate to the container, attach the valve and pressure fill the propellent. Under such conditions, the apolar hydrocarbons were found to cause precipitation of portions of the essential oil in the aerosol unit itself. This was unsightly in a clear bottle, and could also cause staining when unshaken bottles were sprayed. A final problem was the possibility of bottle breakage. During 1977, there were at least four product liability cases in which persons were struck with shards of flying glass. The most costly of these was settled for about $200,000. With the addition of hydrocarbon propellent, a breakage situation could result in a significant flammability hazard as well. Actually, a typical 1-oz. glass aerosol with 13% hydrocarbon will instantly release about 3.1 g of vapor upon breakage. This will produce about 17 gallons of (LEL-basis) flammable gas/air mixture, capable of forming about 25 gallons of flame if ignited by a bathroom hot water heater flame or other source. The possibility of product liability suits was thus seen as significantly increased by the use of hydrocarbon propellents. Faced with all these uncertainties, marketers ceased their promotion of glass aerosol and aluminum tube aerosol fragrance products after about 1974, and directed their research people to concentrate on developing pump-spray alternates. New non-throttling pumps were perfected that eliminated the effects of varying finger speed and gave finer sprays. The outstanding success of firms such as Jovan, Inc. (100% pumps), versus the static performance of firms such as Revlon, Inc. (mixture of pumps and aerosols), gave further impetus to the move toward pump-sprays in the late 1970s. To help salvage the aerosol fragrance market, some marketers developed concentrates that were more compatible with the hydrocarbon propellents, sometimes adding up to 18% water to help separate components that were likewise insoluble in the butanes. The propellent firms developed hydrocarbons that were extremely low in unsaturates content, either by hydro- genation or by employing a special molecular sieving 200 ISO S w loo S p ►J o > 50 7v 4 J T_ 1 \ -E ■ " t- ' ^ / i f t - - "4-X 14 - - - -t zh ^^ - -it- — ' \f \ / \ ys, t I - ^ rf ._. t _ ^ -++ t ,S ~L id-ib^ K_r 60 62 64 66 68 70 72 74 76 78 80 YEAR Figure 5. Aerosol Perfume & Cologne Market Volume
26 The Aerosol Handbook process. These premium priced "Cosmetic Grade" gases were found to be satisfactory by most perfumers. And finally, the Wheaton Industries Co. advocated the use of a special, triple-coated "Lamisol" bottle (adhesive/Rigisol-PVC/Plastisol-PVC) that could be produced on their "E-machine" at rates of 105,000 to 120,000 units per day. They proposed such bottles for aerosols over J4-oz. (15 ml) in capacity, except for low pressure formulas in bottles up to 1-oz. (30 ml) in volume; especially if the amount of gas was low or from 10 to 20% water was present in the formula. The Lamisol bottles were suggested to fill up to at least 4-oz. (180 ml) bottle capacity and pressures to 40 psig at 70°F (21.1°C). With these innovations in place and tested for bodi hydrocarbon and P-152a (CH3 • CHF2) propelled formulations, by about 1979 the aerosol fragrance industry was again ready for expansion. A total of twelve contract filler lines were available, nine in the east, two in the midwest and one in the Los Angeles area. Most of these lines could produce at 60 to 80 bottles per minute. Marketers include Chesebrough-Ponds, Inc., Revlon, Inc., Avon Products, Inc., Coty, Inc., Faberge, Inc., Estee Lauder, Inc. and others, but all are moving into the area with considerable caution. During 1978, one of these firms indicated that their target volume was 35 million units per year widiin five years. Volumes of this magnitude (if coated) could not be produced on the Wheaton aerosol bottle line, and a second line would cost about $1.4 million in 1978 dollars. It would be 157 feet long and take slightly over a year to build. A substantial portion of the present line is used in die production of pharmaceutical aerosol bottles, such as about 6 million bronchodilators for Riker Laboratories, Inc., in 1978. The aerosol cologne formulations have been extended into a number of other products that are not normally thought of in the same context as straight fragance items. One is the perfumed, after-badi talcum powder spray, where Avon Products, Inc. is the undisputed leader. They offer perhaps twenty fragrances in a mini-market, totalling around 18 million units per year in 1981. A 4-oz. fill in a 202 x406 can size is typical. Another is a sachet spray, with about 2 or 3% perfume oil, edianol and hydrocarbon propellent, packed in a 202 x 406 can. It is designed for spraying clothes, either when folding them after washing and drying, or for spraying lingerie and other articles while in die drawer. Many body mists are nothing more than cologne products, although some also contain some rather complicated formulas high in moisturizing ingredients such as squalane and glycerine/volatile-silicone combinations. These products are packed in aluminum tubes (typically 3-oz.) or 202 x 314 to 202 x406 cans. Finally, die after shave, skin bracing formulation contains at least 0.4% perfume in a 50:50 (wt.) water- ethanol mixture, to which a bit of glycol, menthol and higher pressure hydrocarbon propellent are added. The suggested can size is the 202 x 509. The aerosol approach has not been a popular one, since it involves spraying onto the fingertips, then patting down die face, underarm or legs. The application can be made in die same way and almost as easily using die regular glass or plastic bottle forms. Skin Care Aerosols Widi the growing sunbelt population, the increased interest in skin care and sun care products by healdi and beauty editors in die consumer press, and die burgeoning number of older people, sales of skin protective products have suddenly shot up to Brob- dingnagian levels. Typical data on sun care products alone are indicated in Table XVII. The "Coppertone" products are estimated to have more than 31% of the total market and about 50% of the aerosol sector. An indication of the lustiness of this business is the introduction of the "Mmm! What a Tan!" line of lotions and oils in 1980 with a $2 million advertising budget. Product formulas vary widely, but the major sunscreen is homomendiyl salicylate, with about 1.4 million pounds used in 1979 in over half of all units sold. PABA esters, on the other hand, enjoy die largest share of dollar sales. Greasy ingredients, such as coconut oil, cocoa butter (dieobroma oil, USP natural) Table XVII. Market Performance of Sun Care Products Year 1974 1975 1976 1977 1978 1979 1980 1981 $ Volume Total Market 93MM 99MM 118MM 143MM 154MM 161MM 166MM 171MM* $ Increase Total Market 4% 7% 19% 21% 6% 4% 3% 3% % of Population Using Sun Care Products 18 20 23 26 29 32 33 34 $ Volume Aerosol Segment — — 9.5MM 11.0MM 13MM 16MM — — 'Sunscreens grew from 30% to 37%. Plough, Inc. brands, led by the Coppertone line, remained stable at 40% share. Next Page
26 Previous Page The Aerosol Handbook process. These premium priced "Cosmetic Grade" gases were found to be satisfactory by most perfumers. And finally, the Wheaton Industries Co. advocated the use of a special, triple-coated "Lamisol" bottle (adhesive/Rigisol-PVC/Plastisol-PVC) that could be produced on their "E-machine" at rates of 105,000 to 120,000 units per day. They proposed such bottles for aerosols over J4-oz. (15 ml) in capacity, except for low pressure formulas in bottles up to 1-oz. (30 ml) in volume; especially if the amount of gas was low or from 10 to 20% water was present in the formula. The Lamisol bottles were suggested to fill up to at least 4-oz. (180 ml) bottle capacity and pressures to 40 psig at 70°F (21.1°C). With these innovations in place and tested for both hydrocarbon and P-152a (CH3 • CHF2) propelled formulations, by about 1979 the aerosol fragrance industry was again ready for expansion. A total of twelve contract filler lines were available, nine in the east, two in the midwest and one in the Los Angeles area. Most of these lines could produce at 60 to 80 bottles per minute. Marketers include Chesebrough-Ponds, Inc., Revlon, Inc., Avon Products, Inc., Coty, Inc., Faberge, Inc., Estee Lauder, Inc. and others, but all are moving into the area with considerable caution. During 1978, one of these firms indicated that their target volume was 35 million units per year within five years. Volumes of this magnitude (if coated) could not be produced on the Wheaton aerosol bottle line, and a second line would cost about $1.4 million in 1978 dollars. It would be 157 feet long and take slightly over a year to build. A substantial portion of the present line is used in the production of pharmaceutical aerosol bottles, such as about 6 million bronchodilators for Riker Laboratories, Inc., in 1978. The aerosol cologne formulations have been extended into a number of other products that are not normally thought of in the same context as straight fragance items. One is the perfumed, after-bath talcum powder spray, where Avon Products, Inc. is the undisputed leader. They offer perhaps twenty fragrances in a mini-market, totalling around 18 million units per year in 1981. A 4-oz. fill in a 202 x406 can size is typical. Another is a sachet spray, with about 2 or 3% perfume oil, ethanol and hydrocarbon propellent, packed in a 202 x406 can. It is designed for spraying clothes, either when folding them after washing and drying, or for spraying lingerie and other articles while in the drawer. Many body mists are nothing more than cologne products, although some also contain some rather complicated formulas high in moisturizing ingredients such as squalane and glycerine/volatile-silicone combinations. These products are packed in aluminum tubes (typically 3-oz.) or 202 x 314 to 202 x406 cans. Finally, the after shave, skin bracing formulation contains at least 0.4% perfume in a 50:50 (wt.) water- ethanol mixture, to which a bit of glycol, menthol and higher pressure hydrocarbon propellent are added. The suggested can size is the 202 x 509. The aerosol approach has not been a popular one, since it involves spraying onto the fingertips, then patting down the face, underarm or legs. The application can be made in the same way and almost as easily using the regular glass or plastic bottle forms. Skin Care Aerosols With the growing sunbelt population, the increased interest in skin care and sun care products by health and beauty editors in the consumer press, and the burgeoning number of older people, sales of skin protective products have suddenly shot up to Brob- dingnagian levels. Typical data on sun care products alone are indicated in Table XVII. The "Coppertone" products are estimated to have more than 31% of the total market and about 50% of the aerosol sector. An indication of the lustiness of this business is the introduction of the "Mmm! What a Tan!" line of lotions and oils in 1980 with a $2 million advertising budget. Product formulas vary widely, but the major sunscreen is homomenthyl salicylate, with about 1.4 million pounds used in 1979 in over half of all units sold. PABA esters, on the other hand, enjoy the largest share of dollar sales. Greasy ingredients, such as coconut oil, cocoa butter (theobroma oil, USP natural) Table XVII. Market Performance of Sun Care Products Year 1974 1975 1976 1977 1978 1979 1980 1981 $ Volume Total Market 93MM 99MM 118MM 143MM 154MM 161MM 166MM 171MM* $ Increase Total Market 4% 7% 19% 21% 6% 4% 3% 3% % of Population Using Sun Care Products 18 20 23 26 29 32 33 34 $ Volume Aerosol Segment — — 9.5MM 11.0MM 13MM 16MM — — 'Sunscreens grew from 30% to 37%. Plough, Inc. brands, led by the Coppertone line, remained stable at 40% share.
Aerosol Marketing Considerations 27 and parafin wax were replaced in the early 80s with non-greasy items like "UCON Fluid LB-625", C12-C15 alcohol benzoates and polyethylene emulsions, such as '' A-C 627", all of which act to resist water and hold the sunscreen in place for a longer length of time. The aerosol products are usually anhydrous and contain from 35 to 40% of hydrocarbon "A-40" to "A-46" propellent blend. In early 1980, sun screening agents were added to skin care creams, lotions and aerosols. If screening claims are made, the FDA classifies the product as an O-T-C drug, according to proposed rules. But in addition a warning may be used, such as, "Over-exposure to the sun may lead to premature aging of the skin and skin cancer. The liberal and regular use of this product may reduce the chance of premature aging of the skin and skin cancer." Such language is considered very helpful to product promotion. As little as 1 to 2% sun screening agent will give a minimum SPF (Skin Protection Factor) of 2, and this is considered sufficient for products not marketed primarily as sun protection types. For instance, Lanvin-Charles of the Ritz, Inc. recently introduced sun screens to its "Revenescence Moist Environment Body Treatment" and "Optimum Balance" skin care products, and several firms are marketing an aerosolized lotion that incorporates an insect repellent, poison plant urushiol absorbent, sun screen and mild germicide, pressurized with nitrous oxide. The skin care market (considered separately from the sun care segment) increased to about $220 million in 1980. In 1981, aerosols had almost no stake in this business. The current 1980 leader is "Vaseline Intensive Care" (23%), followed by "Wondra" (10%), "Jergen's Lotion" (9%), "Keri Lotion" (8%) and "Rose Milk" (4%, down from a high of 14%). Products by Gillette, "Silkience", and Clairol, Inc., "Condition", are expected to be introduced in 1981, adding to the overall market volume. With proper positioning, many experts feel the aerosol form has a place in the skin care area: perhaps as an elegant aluminum or necked-in 202-diameter can, with a suitable spout and nitrous oxide formula capable of producing a very heavy foam. Insecticides Insecticides represent the original aerosol market, starting in about 1943 with the World War II "Bombs", and graduating to the non-returnable can in 1947. They have had an interesting, if unspectacular Table XVIII. Unit Sales of Aerosol Insecticides; 1970 - 1980 Year 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 U.S.A.* 105 109 127 135 125 102 114 120 132 138*** 150 (Millions England 20 24 26 27 36 42 47 68** 85** 61 62 of Cans) Japan 46.6 51.0 53.4 60.4 68.5 49.0 50.7 59.8 68.9 90.8 68.1 Western Europe — — 179 184 212 203 243 262** 234** — — 'Includes insect repellents but excludes pet sprays, such as flea and tick insectidides. Both categories were about 12 million in 1979. **Many of these were exported, especially by England and Holland. ***The CSMA figure of 199 million units is strongly disputed by industry. growth. Representative production figures during the 1970's are shown in Table XVIII. Several European countries reported sharply decreased consumption of insecticides during the 1970s. For example, France dropped from 30 to 14 million, and Italy dwindled from 53 to 31 million during the 1974-1978 period. The Netherlands showed a level production between 1972-1978, but after 1976 about half of this was exported to Nigeria, the Middle East and other locations. There are four major subdivisions of the insecticide category. They are shown in Table XIX, compared in volume sales with the two main liquid categories. Table XIX. Aerosol Product Sales During 1979 - 1980 Type and Class Per Cent of Combined Liquid & Aerosol Sales Aerosol Residual Spray Aerosol House & Garden Aerosol Flying Insect Killer Aerosol Fogger (Indoor and Outdoor types) Liquid Residual Sprayer Liquid Flying Insect Killer All Others - Aerosol & Liquid (As Hornet & Wasp Sprays, Mothproofer Sprays, etc.) 1979 35 10 16 13 23 2 1980 36 9 14 13 25 2 Solid types, such as mosquito strips, powders, roach traps and pastes are not included.
28 The Aerosol Handbook Insecticides are highly seasonal. Sales during the first three months of the year are at levels in the range of 7 to 20% of sales during early May, depending on class. The residual aerosol is the largest single class, with 1979 sales of 48 million units and 1980 sales of over 54 million units. The residual insect spray is composed of about 1 or 2% of active materials, dissolved either in low-odor petroleum distillate, or blends of that solvent with n-butyl Cellosolve and other liquids in order to dissolve certain solid toxicants, such as the carbamate types. The propellent is almost always C02, although two intermediate size marketers use hydrocarbon blends. The active ingredients are toxic substances at this time, but technology has been developed on the use of "bio- rational pesticide" materials, such as biochemical pest control agents isolated or derived from natural sources (pheromones, insect growth regulators, enzymes, etc.), microbial agents and other ingredients whose pesticide efficacy is not based on inherent toxicity. The EPA, which acts to pre-register and control all insecticides, has looked favorably upon these new agents and may reduce significantly the development data requirement in order to get them onto the market in greater 62 64 66 68 70 72 74 76 78 80 YEAR Figure 6. Aerosol Insecticide Market Volume Includes insect sprays for animals; excludes insect repellents. For 1979, the 199 million unit CSMA figure is discounted in favor of figures from other marketing reports. numbers. Only one or two types appeared commercially in 1981. The largest insecticide class for flying insects is the oil-out emulsion formula, where the active ingredients amount to only a few percent, the balance of the formulation being about 65 % deionized water (with detergent, inhibitors) and possibly a perfume), and 30 to 32% hydrocarbon propellent in the A-40 to A-46 range. Pyrethrins have been used classically for such products, but their use is dwindling, due to the present price of about $200/lb. (100% basis) and the long term uncertainty of supply. The use of various forms of allethrin, resmethrin, sumethrin and neo-pynamin is increasing; the last of these was priced at about $57/lb. in 1981. Some insecticides have been developed in France and Japan that are rated at 10 to 50 times as bio-toxic as pyrethins, but they have not been used in the U.S.A. to any extent, as of 1981. The major insecticide marketers include S.C. Johnson & Son, Boyle-Midway Division, Chevron Chemical Co. and the d-Con Co., Inc. Each has a substantial line of individual products. Special insecticides have been developed for use in food kitchens, dairy barns, for aircraft disinfection and for flea and tick control on pets. One unique formula uses dry, finely divided silica as a toxicant. This inside fogger, with 17% of the market, is designed to lock open and spray to emptiness, ridding an entire house of insects. The aerosol pet spray market has remained fairly static at about 19 million units per year. Nevertheless, with Americans owning some 48 million dogs, 27 million cats, 25 million birds, 250 million fish and 125 million assorted other fauna, (44.6 million American households included a pet in 1980), the potential for increased sales is certainly a real one. About two-thirds of the aerosol market is held by insecticides, mainly dog flea and tick sprays. Insecticidal cat sprays and pet shampoos with insecticidal properties are less important. Other products include miticidal products for birds and birdcages, grooming aids, litter-box deodorants and training sprays. Indoor and outdoor dog repellents are generally placed in a separate category. They include formulas based upon methyl nonyl ketone, to prevent the phytotoxic and/or staining effects of urination. More recently an off-shoot of the $44,000,000 "Mace" market has developed to afford protection against wild or rabid small animals. The combined category unit sales volumes are shown in Figure 6.
Aerosol Marketing Considerations 29 Cigarette Lighters Disposable cigarette lighter packs are not considered an aerosol category in the U.S.A., but are in a number of other countries. Of the 275 million produced in 1980, about 150 million were made by the Bic Pen Corp., 75 million by Gillette Co., and about 50 million by Colibri Corp. of America and other marketers. Worldwide disposable cigarette lighter sales increased from 45 million units in 1971 to about 800 million in 1980. The lighters sold for as little as $0.29 each in the U.S.A. during 1981. Insect Repellents In 1979 the overall market for insect repellents was about $22 million, down from the $35 million level in 1971, but growing to a probable $27 million pace in 1980. About 80% of the business is held by S.C. Johnson & Son, Inc. with their various "Off brand products, and aerosols accounted for about 70% of the total. Other important marketers include Cutter Laboratories Inc. and the d-Con Co. Inc. division of Sterling Drugs Inc. As of 1981, the growth of non- aerosol types exceeded the aerosol segment. For example, Cutter Laboratories Inc.'s Consumer Division has reported that their "Cutter Stick" repellent showed a sales growth of 129% in 1978. "DEET" (N,N-diethyl-m-toluamide) is the principle active ingredient and is commonly used at 20% in the aerosol products. The spray aerosols used ethanol as the diluent and small amounts of either hydrocarbons or CO2 as the propellent. Aerosolized lotions are also available here and there, often using N2O to produce a very dense, easily spreadable foam. "DEET'' gives very effective protection against most mosquitos (which the other important repellent: "6/12", 2-ethyl-l,3-hexandiol does not), but neither are effective against several important biting insects, such as the Bodega Black Gnat (Leptoconops kerteszt). "R-ll" and "R-326", offered by the MGK Co. are also used to a slight extent. Furniture Polishes This category first became important in about 1963 and grew to about 100 million units in 1970 and 109 million in 1972, when the older oil-in-water emulsion polishes slowly gave way to the new water-in-oil types, as exemplified by brand leaders "Pledge", offered by S.C. Johnson & Son, Inc. and "Behold", marketed by The Drackett Products Co. The market in 1980 is estimated at about 130 million units. This is the household product category and does not include the automotive polishes which amount to about 5 million units. Other significant marketers are Colgate Palmolive Co., with their product "Woodcrafter", Alberto-Culver Co. offering'' Kleen Guard'' and Scott, marketing'' Liquid Gold". Except for "Liquid Gold" and several very small volume paneling and cabinet sprays, the usual furniture polish contains about 5% silicones, waxes, perfume and emulsifier, 20% odorless petroleum distillate of the naptha, ligroin, petroleum ether, benzine or heptane type (typical TCC flashpoint = 40°F or 5°C), 63% water and 12% hydrocarbon propellent blend. About 85% of all U.S.A. furniture polishes contain silicones, representing about a $15 million market in 1980. The addition of silicone products provides easy care and a higher gloss but evaporation may eventually dull the finish. When the silicone gets into the varnish or lacquer, refinishing becomes more complex. A long term problem with the water-based polishes is that they have the ability to lift and crack thinly applied finishes. The furniture polish market is more advanced in the U.S.A. and Canada than elsewhere. For instance, in 1979 only 6.9 million units were sold in Japan. It is also interesting to note that retail prices have not increased in the United States during the last ten years or so. For example, a 14-oz. (400 g) can of "Kleen Guard" sold for as little as $0.84 during 1981. Paints, Coatings and Finishes This market is one of the largest in the industry. At its high point in 1977 it accounted for 15.4% of all aerosol products, but this will decrease to about 13.5% in 1981 for a variety of reasons. The modest decline is mainly due to a relative lack of advertising, with marketers saying there is no longer enough profit to justify investing in media activities. In a related move, a disproportionate amount of SKUs (shelf space rating) are pushed toward high end-cost specialty paints, since so little money can be made at the low end. The low end is thus offered less, and consumers are balking at the apparent price increases. Some low end quality problems are becoming more noticeable, such as lack of ''one-coat hiding power'' ''washability'', "durability'' and so forth. Some consumer groups are now pressing hard for a rating system, to avoid disappointments after getting the can home and using it.
30 The Aerosol Handbook Table XX. Unit Sales of Aerosol Paints; 1974 - 1980 (Millions of Units) Year 1974 1975 1976 1977 1978 1979 1980 U.S.A. 257 278 306 331 309 301 286 England 13.0 15.0 16.5 21.5 28.0 28.5 24.0 Japan 16.9 18.4 23.4 27.9 35.7 38.2 36.3 Western I 45 45 50 64 88 — — Recent sales figures show that aerosol paints are growing rather well in Europe, but only slightly in Japan, while U.S.A. sales have been slighdy negative since 1977, see Table XX. The increases abroad are said to be due largely to the continuous introduction of new and improved items, along with more trade show and media promotional activity. The market is very highly segmented. Scores of marketers fill their own products and often fill for others as well. The number of paint shades is legion, and therefore the size of any one production run is apt to be quite small, with cans generally paper labeled. Possibly the largest single run of any paint product took place in 1980 when New York Bronze Powder Co. ran slighdy over 500,000 lithographed cans of a specialty spray enamel, called the "Nearest Thing to Chrome''. Many paint fillers sell directly to retail accounts. Some have between 500 and 1000 accounts, which means that business procedures often get quite complex. The five-year outlook for the U.S.A. aerosol paint business seems to indicate a slow decline to a plateau in the 250 million units per year area, since the industry is not generating any more new users except in the younger (replacement) bracket. The inexpensive $0.99 paints are devastating the good $1.49 types, turning the profit picture downward with resulting cuts in quality control, formulation options (acetone is now replacing methylene chloride, and solids content is being reduced), the use of fewer directional and more cheaper sprayheads and so forth. In 1980 a DME type water- based paint formula was developed by Conn Chem Div. in Toronto, followed by other water-based paints patented by Seymore of Sycamore, Inc., Sycamore, IL. Perhaps these innovations will act to free up some advertising funds to help ward off the general slow dwindling of the overall market. In England, 1979 paint sales were up 2%, to 28.5 million. Laundry Aids About 30% of all households used starches and siz- ings during 1980 and 1981, generating a business of about $45 million. The leading starch is "Niagara Spray" starch with "Easy On" starch running an important second place. In the related sizing field, the acknowledged leader is "Magic Sizing" with a 70% share. All non-aerosol alternates amount to less than 10% of the starch and sizing category. Laundry prespotters in all forms make up a $130 million business, being used by 46% of all households. But here the heaviest sales are in the liquid product area. They do not have the size limitation and higher per ounce cost of the anhydrous aerosol counterparts, and may impart less residual "kerosene type" odor to fabrics because they are water-based. The leading aerosols are "Spray 'n Wash" and "Shout", but both are slowly declining in sales volume. Air Fresheners (Including Disinfectant/Deodorants) This rather large market is divided into two distinct product types: the air freshener and the alcohol-based disinfectant/deodorant sprays. Nearly all air fresheners consist of 0.4 to 1.0% perfume, about 68% water, small amounts of emulsifier and inhibitors, and about 30 to 32% of hydrocarbon propellent blend in the A-40 to A-46 range. A few have actual deodorant materials, such as 3,5,5-trimethylhexanal. Still fewer are ethanol or isopropanol based, with these solvents replacing the water in order to give a more elegant, drier spray. The other variety is characterized as a surface disinfectant and space deodorizing product. It contains typically Table XXI. Unit Sales of Air Fresheners (Including Disinfectant/ Deodorant Aerosols) in 1970 - 1980 Year 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 U.S.A. 162 164 176 188 202 153 125 136 132 122 120 England 13.0 — — — 25.0 23.0 28.5 25.0 35.0 30.0 37.0 Japan 2.1 2.4 4.3 9.5 7.7 11.2 11.1 8.2 8.9 8.5 7.8
Aerosol Marketing Considerations 31 either about 0.1% of o-phenylphenol (or similar) or mixtures of quaternary ammonium chlorides, with about 15% water, a large amount of ethanol, traces of corrosion inhibitors, perfume and other substances, and either 20% hydrocarbons or 5% carbon dioxide. The unit volumes sold in the U.S.A., England and Japan are shown in Table XXI. During 1981, mass merchandiser retail prices for aerosol air fresheners were as low as $0.88 per 7-oz. water-based type and $1.14 per 7-oz. disinfectant/deodorant type. Marketer advertising strongly favored the various alternates, such as the odor absorbent canister products, indicating that the aerosol forms may suffer further sales reductions. Home Insulation Aerosols A new aerosol market has been generated in the early 80's as a result of the increasingly high cost of home heating and air conditioning. It is based upon two product types: polyurethane foam and caulking compounds. The rigid polyurethane foam had its beginnings in the U.S.A. about 1960, when Allied Chemical Corp. showed sample cans of a two-component system to the industry as a sales promotional tool. A can of toluene isocyanate and one of a polyol/catalyst/propellent were combined by pressing the (special) valves together so that the high pressure mixture flowed into the non- pressurized unit. The final can was shaken, whereupon it became very warm, fluid and ready to use. This cumbersome process, also somewhat dangerous due to the toxicity of the isocyanate, was not a marketing success, and the industry awaited the development of a single component system. Several years later, single packs were developed in West Germany, and still later the ICI formulas started to appear in Europe. They were unreliable, often becoming very thick or solid in the can after five to ten months storage. The foam also formed a hard, adherent core in the valve nozzle between uses. In 1977, the first of these products appeared in the U.S.A., under the tradename of "Great Stuff', marketed by Insta-Foam Products, Inc. firm under a license from Rubicon Chemicals, Inc. For a long while it had the drawbacks of the early European formulas, but it appears that these are now resolved. Other U.S. follower products include "Poly Cell", made by the Poly Cell Division, W.R. Grace & Co.; "Foam-O-Fill" (filled in Ohio, using German technology); "Easy Insulator", by Scott-Page, Inc., and "Touch-n-Foam", by the Convenience Products Division of Clayton Corp. During 1981, this market was estimated as about 5 million cans per year in the U.S.A. with a value of about $15 million wholesale. Retail prices varied between $4.99 and $6.99 per standard 14 av. oz. (400 g) can, except for the "Touch-n-Foam" product, where the marketing approach is one of lower prices; e.g. about $2.79 per unit. The growth rate is about 30% per year, based primarily upon "Great Stuff' figures. Since probably less than 1 % of potential buyers are even aware of the product, the sales potential is very large. "Great Stuff' now holds about 65% of the U.S.A. market. Some growth retardation came about as a result of product instability in the can, now corrected, at least in one or two formulations. One marketer sought to convince buyers that the problem was corrected by encasing the can in a polyethelene bag containing "Drierite'' granules. In the case of "Easy Insulator", the marketer claims a minimum shelf life of 14 months, according to tests still in progress. Mass merchandising techniques were still largely untapped in 1981, although Insta- Foam Products, Inc. made a beginning by using point of purchase type materials, such as display cases tied into a fall presentation by a home center, placing the display next to fiberglass insulation and similar energy- saving commodities. There are two distinct use patterns. The builder/contractor now purchases about 20% of the U.S.A. volume (80% in Europe) for foam insulation, especially around window bucks and door jambs. This is an especially large market for the "Poly Cell" product. The rest of the purchases are made by the home handyman, who uses the foam to fill large crevices between the masonry foundation and the wood sills of the house, around electrical oudets where an air draft is indicated, around ducts or pipes where they go through sheetrock or other walls and so forth. In many cases a number of cans are required. Fortunately the government allows a substantial tax credit on such energy-saving purchases. The can is in the 211 x 612 range, and generally in a "DOT Specification 2Q" strength to withstand the pressure increase that accompanies the exothermic reaction of the isocyanate and polyol ingredients, when they are added (separately) to the can, and then mixed quickly together with a shaking operation. A temperature rise of 55 °F (30 °C) is sometimes seen, although the usual increase is about 45 °F (25 °C). A Clayton Corp. valve is used, normally with a nylon stem,
32 The Aerosol Handbook although the "Poly Cell" product uses a special Swedish valve. Polyethylene adapters and Vi " (7mm) diameter straws are often used to inject the product into deep cracks and crevices. After use, the product forms a solid plug in the last inch or so (about 25 mm) of the straw, and this much is then snipped off before the next use. The standard 14 av. oz. (400 g) fill is sufficient to produce as much as 175 feet (53 m) of Yi inch (12 mm) diameter bead, or the equivalent of around 15 standard 11 av. oz. (312 g) tubes of caulking compound. The primary ingredient is an isocyanate, either toluene isocyanate (as in "Great Stuff') or the less volatile and thus lower toxicity methylene diisocyanate (MDI), which is used in "Easy Insulator". The isocyanate is mixed in the can with about 0.8 part of a special polyol. A bit of reaction catalyst is also needed. This can be added as a separate ingredient, such as an aliphatic amine, or internally, as a part of the structure of the polyol. The isocyanates are available from Mobay Chemical Corp., Upjohn Co., Rubicon Chemicals, Inc., and Union Carbide Corp. The polyols can be obtained from Dow Chemical co., Mobay Chemical Corp., Union Carbide Corp., Wyandotte Corp. or other suppliers. All have relatively low equivalent weights and a moisture content of 0.15% maximum, or 0.08% typical. If water is present above about 0.20%, the aerosol product will undergo a degree of thickening that will render it unusable in many cases. The Environmental Protection Administration allows the use of chlorofluorocarbon propellents in these products, and indeed they are often found to be the propellents of choice. "Great Stuff' uses a blend of P-ll and N2, while Foam-O-Fill contains P-ll and P-12. "Touch-n-Foam" uses 20% hydrocarbon A-70 blend. About 30% of a 90:10 mixture of P-12 and dimethyl- ether (DME) has been found ideal for certain formulas. The product is extruded from the aerosol as a very rough-surfaced foam. Upon standing, it rapidly undergoes a secondary expansion, with an evening out of the surface, forming a fairly hard, glossy crust. It is strongly adherent to most surfaces. Flexible polyurethane foams can be made by reducing the cross-linking density of the polyol, so that a preponderance of linear polymer is formed. The caulking market is now about $250 million in the U.S.A. and acrylic emulsion products like "Easy Caulker'' have brought the aerosol into this new arena. At least 2 million units of the product should have been sold in 1981, for a retail sales volume of $10 million. "Easy Caulker" is delivered as an exceptionally dense foam and is most useful in filling gaps or crevices of V2 " (14mm) or smaller, leaving the larger ones to the poly- urethanes. The 11 av. oz. fill is the equivalent of 4 caulking cartridges, and sufficient to lay down as much as 140 feet (43 m) of V* inch (7 mm) bead, smooth on top and conforming to the surface. Growth of this market is estimated as 30 to 100% per year, since market reception has been phenomenal. Food Products Food aerosols have long been an enigma to marketers. They have become important only in the U.S.A.; other countries have only a few million units per year at best and many have none. Regulations in the U.S.A. have limited propellent choices to n-butane, isobutane, propane, CO2, N2O, N2 and Freon Food Propellent C-318 (perfluorocyclobutane), although some of these are not permitted to be used in other countries — most notably N2O. Rather interestingly, N2O is generally denied because of its anesthetic qualities (laughing gas), yet this effect can only be obtained upon breathing large amounts of the virtually pure propellent gas, something that is impossible to do with an aerosol can. Outside the U.S.A., the use of P-ll and P-12 is sometimes permitted in the formulation of cookware sprays. In Canada, P-ll is still allowed, on the basis that it is a solvent, not a propellent. The largest food category is the whipped cream product, dating back to the late 1940s as one of the earliest of all aerosols. The concentrate is a synthetic dairy cream, compounded and pasteurized immediately before filling. It is cold filled into cans of about 18 fl. oz. (typically 564 ml) capacity, filling them about 60% by volume with product. The units are sealed with a suitable valve and either CO2 or N2O propellent is introduced by a gasser-shaker process until the pressure reaches the equivalent of about 110 psig at 70°F (21.1 °C). In a few cases, a particular blend of CO2 and N2O is used, where the tartness of the first is counterbalanced by the sweet taste of the second. The Avoset Co. has long been a leading captive and contract filler in the filling of sterile whipped cream aerosols. The finished concentrates are flash sterilized by heating to about 280°F for such a brief period that there is essentially no cooking or browning of the ingredients. From this point on they are handled in a closed sterile transfer system, going into a special Hope filler,
Aerosol Marketing Considerations 33 and then into aerosol cans that have been sterilized by very brief heating to about 450°F. Chemically sterilized aerosol valves are applied and crimped in place, after which the units are gassed with CO2 (generally) that has been passed through a 0.2 micron filter to strain out any trapped microorganisms. The finished units do not exhibit any spoilage, but at room temperatures there is a slow degradation, probably the result of enzyme related chemical changes. Because of this, the units are stored at about 34° to 38°F (1° to 3°C), remaining stable for well over a year. The whipped cream products are filled by specialty firms that have the necessary heat exchange units, refrigeration rooms and other production requirements. The major contract fillers do not participate in this business. Since the non-sterile types undergo a slow degradation, even when stored below 40°F, arrangements are usually made to provide for the swift delivery of finished stocks to retail outlets (using refrigerated trucks), where they are then sold in store coolers. The U.S.A. consumption of aerosol food products is described in Table XXII. The second largest category of food aerosols is the cookware spray, sometimes called the frypan lubricant. This product was pioneered by Gibraltar Industries, Inc. under the name "Pam", originally a dispersion of 3% selected lecithin derivative in 97% P-ll/P-12 chlorofluorocarbons. A small amount of isobutane was later introduced as a cost-cutting measure. The formula was so elegant and effective that it remained unchanged until the FDA mandate to curtail use of chlorofluorocarbons barred it from further sale in 1978. In the interim Gibraltar Industries Inc. had been purchased by the Boyle-Midway Division and was operated as the Pam Products Unit of that firm. Contingency refor- Table XXII. Unit Sales of Food Aerosols Including Whipped Cream Products; 1972 - 1980 (U.S.A.) (Millions of Units) Year 1972 1973 1974 1975 1976 1977 1978 1979 1980 All Food Aerosols 90 112 122 150 151 125 143 141 130 Whipped 1 46 57 48 70 73 64 67 71 60 .1 Figure 7. Various Aerosol Fry-Pan Release Products Lecithin is used to prevent the sticking of food residues to cookware. GOLDEN TOUCH, LEAN FRY and PAM are products of Boyle- Midway Division. MAZOLA NO-STICK is a product of the Best Foods Division of CPC International, Inc. All are low calorie, except for GOLDEN TOUCH and COOKING EASE, which contain considerable amounts of vegetable oil and may be used for basting, "buttering" popcorn, potatoes and so forth. mulation work started about 1975, carrying through ethanol compositions and so forth until the present line of products was developed. Similar activities were carried out for the second-place brand, "Mazola No-Stick", a product of the Best Foods Division, CPC International Inc. Now in 1981 at least 25 frypan lubricant sprays are available (some strictly institutional), and nearly all of the water-based type. Their combined unit volume was estimated at about 40 million (in 1979 and 1980). The water-based versions use the lecithin and sometimes an auxiliary non-ionic food-approved surfactant to achieve a reasonable stable emulsion, which is then pressurized with about 20% hydrocarbon propellent. Traces of color, flavor, citric acid and other items are often added. The water is present only to make the overall product essentially non-flammable. In contrast to the clear films laid down by the anhydrous predecessor products, water-based sprays produce an opaque, yellow-white foam layer which has undoubtedly made millions of customers wonder if they received the correct product. The thin foam coating dries out quickly when the frypan is heated, leaving a translucent or transparent film behind. If the coating is sprayed directly into the pre-heated frypan (ignoring label directions to avoid such action) the result is vigorous boiling, steaming and popping of water globules that can sting the hands if one gets too close. An interesting offshoot of the frypan lubricant is the vegetable oil spray. It is possible to disperse up to about
34 The Aerosol Handbook ft- fM*4W* I* RILtf Figure 8. A Grouping of Aerosol Food Items The Butter Flavoring Spray and Imitation Grape-Ade Spray Mix (plus other items) were sold by the Jewel Home Shopping Service Division. The can of TOPPEROO Ice Cream and Desert Topping (Marshmallow and three others) were test marketed by the Best Foods Division of CPC International, Inc. The aluminum piston- operated can of SNACK MATE American Pasteurized Process Cheese Spread (plus other cheeses) is marketed by Nabisco, Inc. 2.5 to 3% lecithin derivative in corn oil (or the less expensive soy bean oil) then add butter flavor and a carotene colorant. This gives a "butter oil" which also has pan release properties. To aerosolize, about 4.4% N2O or 4.2% CO2 is added by a gasser-shaker operation. The resultant product is dispensed as a fairly coarse spray, suitable for "buttering" popcorn, spraying upon vegetables, lubricating frypans and giving a pleasant butter flavor to eggs or other items to be fried, even for the very rapid "buttering" of sliced bread or toast in institutional kitchens. Specific popcorn sprays do not require the lecithin ingredient. They can be applied to popped popcorn, but even better, they can be used to spray unpopped kernels (salted) in a hot air or other popper, so that when the kernels pop they will become coated with butter flavored oil which can then act additionally to hold the desired salt onto the surface. The sales volume of this innovative product was only about a million units per year in 1981, but it seems destined for growth. Two food products are somewhat unique in that they are packaged in "Mira-flo" (piston-type) 202 x405 aluminum cans. Their combined volume, as reported by The Can-Maker's Institute, was 30 million units in 1979. The larger, estimated at about 25 million units, is a sizable line of 4-oz. cheese spreads, marketed by Nabisco, Inc. The other product is a cake decoration icing, sold by Pillsbury Co. It can be used to lay down various inscriptions or designs on iced cakes, and several colors are available. A large number of food aerosols have come and gone, and of course many potential products never quite made it to the store shelf in the first place. Some interesting ones can be mentioned. One is a soft drink concentrate, capable of producing from 17 to 50 non- carbonated beverages per can. Problems involved can corrosion (eventually), since several were acidic citrus types, pressurized with CO2, which itself forms carbonic acid in water, plus consumer problems with putting in the proper amount into the ice water base. A chocolate syrup additive for milk drinks often resulted in a doubling of the amount of milk consumed, so that secondary economic considerations argued against repurchase. A puffed mayonnaise product was offered on the basis that it had fewer calories per teaspoonful, but consumers perceived it as a new item, with no connection with ordinary mayonnaise, and were confused as to what to do with it, other than decorate jello-type preparations. Ice cream toppings are feasible, in such flavors as marshmallow, cherry and chocolate, but only can be prepared using a typical 9 av. oz. (255 g) can. After a lengthy research program, an aerosol pancake batter was developed about 1972, but the cost per pancake was considered excessive: one four-inch (100 mm) diameter pancake per ounce (28 g) cost $0.14 (1982 dollars). There were heavy costs in the batter processing system required, and the ever present faint possibility of a marketing and product liability fiasco in the event something should go wrong and allow microorganisms to proliferate in the aerosol can; this despite thousands of microbiological tests that gave the product a clean bill of health, if made correctly. The "Sepro" can, marketed by the Continental Can Co. since the early 1960's, has received some attention in terms of food aerosol developments. Products such as peanut butter, butter, margerine, jellies, honey, toothpaste have all been looked at, and the last two are commercially available, almough in very low volume. The high package cost has been a significant deterrent. Also, there is a certain imagery that food aerosols have insecticide cousins and should not be placed on the table, along with condiments and other food items. Given all these constraints it is reasonable to suggest that there will probably not be any particular flare of activity in the food aerosol segment during the next few years.
Aerosol Marketing Considerations 35 Aerosol Production A majority of marketing analysts believe that the aerosol industry has reached the point of saturation in the U.S.A., Canada, many Western European countries, and so forth, and will not continue to grow beyond the increments related to population growth unless significant new products are developed. Perhaps the highest aerosol sales density ever recorded took place between about mid-1973 and mid-1974 in the U.S.A., when a volume of significantly over 3 billion units per year drove per capita consumption to 14.1 units per year. In contrast to this, the per capita use during 1979 in various major markets is shown in Table XXIII. The 28% decrease in per capital usage between the peak year and 1979 in the U.S.A. is due largely to the exceedingly bad publicity and government regulations that followed in the wake of the CFC/ozone controversy that surfaced in 1974. (The added effect of the 1980 recession widened this to a 35% decrease, since per capita usage was only 9.15 units.) ~ 2. w J o > o s 8 £ 0 0 -■ ._ — — '■" PERIOD Overheated economy cession —|— Onset of CFC controversy — — — -- —\- \ * -t- — t- h.t 4_. -4 4--i .... -- ■ h — 1970 TO -4 - cession 1990 ..-;44-|+i- i i i i sion K IS iHk '* j 4^ ! "T TTi^ y± dP^"'"H"^ h - { - - • : -1-1 -1- - -i j +-4--<- • - ' T-t -+ 1 - \-\-\ I l -* l '< \ ' ' ; i : W//////////////////, nnhHritv and regulations i — —i -■h- h-H - -n- r i T 1 —- ...-4-4 .-. ; -, , -, , - i ■ .— | -4 -J \ +- - <- + { 4- ; i ' i I I I 1970 72 74 76 78 80 82 YEAR Figure 9. Difference between Demand in the Absence of CFC Regulation and Demand with Regulation Table XXIII. Worldwide Consumptior Market U.S.A. England The Netherlands Australia France West Germany Switzerland Canada Austria New Zealand Italy Greece Norway Finland Argentina Republic of South Africa Japan Mexico Sweden Brazil of Aerosols in 1979 Million Units Sold 2,398 498 175 135 429 462 47 134 39 13 252 28 10 18 94 72 311 71 11 101 Other Latin Amer.Countries 145 Other African Countries 136 Units Per Capita 10.20 8.90 9.97 8.98 7.73 7.34 6.94 5.74 4.92 4.18 3.65 3.21 2.96 2.94 2.89 2.88 2.62 2.19 1.45 0.96 0.07 Year 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973** Table XXIV. Production and Uses of Chlorofluorocarbons World Production (Billion Pounds) 0.23 0.28 0.33 0.36 0.44 0.52 0.61 0.68 0.79 0.87 0.99 1.13 1.23 1.34 1.52 1.73 1974*** 1.86 1975 1976 1977 1978 1979 1980 1.58 1.70 1.62 1.53 1.48 *Estimated. During 1958 to 1980 Western Nation Production (Billion Pounds) 0.22 0.27 0.32 0.35 0.43 0.50 0.58 0.64 0.74 0.81 0.93 1.07 1.16 1.27 1.44 1.65 1.791 1.65 1.64 1.54 1.45 1.40 U.S.A. Production (Billion Pounds) 0.90 0.80 0.86 0.90 0.93* * * Base year for many calculations. P-11 and P-12; U.S.A. Sales (Billions of $) 0.40 0.37 0.41 0.44 0.50* U.S.A. CFC Aerosol (Billion Units) 0.11 0.32 1.36 1.30 1.47 1.67 1.41 1.13 0.92 0.55 0.21 0.03 0.02 ***Peakyear.
36 The Aerosol Handbook Table XXV. Propellent Selection for Aerosols Filled in 1979 (%) Country U.S.A. England France West Germany Italy Denmark Belgium The Netherlands Canada Mexico Fluorocarbon 1 68 70 67 60 55 50 20 11 47 Hydrocarbon 90 30 25 23 30 40 28 62 82 51 D.M.E. 0 0 0 0 0 0 18 15 0 0 C02/N20/N2* 9 2 5 10 10 5 4 3 7 2 "In the approximate ratio of 85:14:1. The graph suggests a loss of about 4.33 billion units up to 1990, after which it is assumed the controversy should have no further impact on aerosol usage, even it it has not been resolved scientifically by that time. Using the CSMA figure of 2.165 billion units for 1980, this loss of business adds up to two full years of production. Actually the analysis shown in Figure 9 is extremely conservative; other econometric studies point to losses of two to five times this amount. The U.S.A. position against chlorofluorocarbon gases has been the subject of endless debate. Aerosols were the first target of the EPA and FDA. The effect of their regulations, plus the international activities of the EPA in trying to achieve wider bans on chlorofluorocar- bons, is shown in the following Table XXIV, from which it is apparent that sales diminished after 1974 on a worldwide basis. Despite the increasingly obvious defects and shortcomings of the Rowland-Molina theory, where these researchers tried to explain three-dimensional atmospheric phenomena using a one-dimensional computer study, the EPA strove vigorously to export the U.S.A. position on banning CFC aerosols to a variety of other nations. They received mixed reactions, more generally on the negative side. About 1979 Canada agreed to a partial ban on fluorocarbon propellents, where they were used as true propellents for hair sprays, personal Table XXVI. Aerosol Productions During 1979 Product Insecticides (Non-pet) Air Freshener (& D/D) Waxes & Polishes Oven Cleaners Laundry Aids, as starch Other Household Products Hair Sprays Cologne/Perfumes Antiperspirants & Pers Deod. Shaving Creams Other Personal Products Medicinals Foods Paints and Coatings Automotives Industrials (Other than Paints) Animal Products Other Miscellaneous Products Total Household Products* Total Personal Products Total Miscellaneous Products* Total Aerosols (Excluding the butane cigarette lighters) Butane Cigarette Lighters U.S.A. 131 122 140 38 117 235 238 32 268 137 97 26 141 271 166 134 16 88 784 772 842 2,398 275 Canada 10.5 8.0 10.5 2.6 3.5 11.0 13.0 7.5 20.5 8.0 3.5 6.6 3.5 17.0 5.5 1.5 1.0 0.3 46.1 52.5 35.4 134.0 N.A. England 60.5 30.0 43.5 5.0 13.0 10.0 103.5 64.5 52.5 18.5 8.0 34.0 2.0 28.5 31.5 13.0 2.0 2.0 162.0 247.0 113.0 522.0 26.3 Japan 89.1 8.4 6.9 3.3 20.5 26.9 57.2 1.2 19.1 5.6 7.4 9.1 1.2 38.2 14.3 27.1 1.6 3.1 156.7 90.5 94.6 341.8 23.0 Switzerland 0.6 1.5 0.4 0.9 0.9 6.4 11.9 5.2 7.2 1.6 4.6 1.1 0.1 3.1 1.8 0.9 0.2 1.6 10.7 30.5 8.8 50.0 N.A. "These categories are patterned from the English (BAMA) figures, not the U.S.A. (CSMA).
Aerosol Marketing Considerations 37 deodorants, antiperspirants and colognes. In 1980 Sweden effected a ban, followed by one in Norway, and Western Europe generally agreed to try to limit utilization of CFCs to 70 % of their former levels, over a three- year period, the cumulative effect of bans, planned reductions, recessions, marketer indecision, adverse consumer reaction, consumerist positions and other factors has been that the 1980 sales of P-l 1 and P-12 are now about 36% below the level which would have been predicted in the absence of the Rowland-Molina theory, the bad press and all the socio-economic problems which followed. The loss is estimated as about 880 million pounds (400 Kilotonnes or 400 Gg). During the 1973-1977 five year period, U.S.A. consumption of CFC dropped about 67%, and U.S.A. aerosol production fell from about 50% of world aerosol production to about 33%. The 1979 situation for aerosols filled in various countries is shown in Table XXV: In 1977 worldwide manufacture of aerosols accounted for 48% of all P-l 1 and P-12 production. By 1978 this had dwindled to 43%, with refrigeration and air conditioning uses remaining in second place with 31 % .Japan appears to be the fastest growing CFC producer, manufacturing 141 million pounds (64 Kilo- tonnes, or 64 Gg) during 1980. Approximate figures for aerosol production in several countries during 1979 are given in Table XXVI. Figure 10. vr — Aluminum -j j Tubes for 5 - j Personal 3 ) Protection a <*■ ' Products. The containers are % " (22mm) diameter tubes. Both have 20 mm ferrule-type valves and special actuating heads. Figure 11. Japanese Anti-Static Products for Garments The Japanese dispenser is smaller and the product is more distinctly perfumed than U.S.A. counterparts. A special actuator covers the valve cup. The use of data on aerosol productions can be very misleading. For example, the production of insecticides in England rose from 42 million in 1975 to 85 million in 1978. What might seem to be a dynamic market was actually one where domestic consumption was at the saturation point of about 19 million units, with all the rest being exported. Another statistical tool that is badly overrated is aerosol market share, as shown in Table XXVII. Table XXVII. Market Share of Selected Aerosol Products U.S.A. 1980 Product Insecticides Insect Repellents Spray Disinfectant/Deodorants Bathroom Cleaners Starch Sprays Sizing Sprays Oven Cleaner Sprays Upholstery Cleaner Sprays Window Cleaner Sprays Shave Creams Hair Sprays Antiperspirant/Deodorants Colognes/Perfumes Sun Care (Sun Screen) Aerosols Refrigerated Toppings Caulking Compound Market S 74* 70 71 11** 68** 18** 86 98.4 9 94 62 39 5 7.7 11 1 *Of the aerosol plus pump-spray market. **Of the all-purpose cleaners category. ***Of the dry, liquid and aerosol starch, plus sizings market.
38 The Aerosol Handbook Aerosols with small market shares in their category might appear destined for growth, but this is not usually the case. Conversely, aerosols with a lion's share of their overall category can experience growth, simply by expansion of the category itself, as in upholstery cleaners, during 1980 and 1981 to date. Marketers customarily evaluate the sales performance (both volume and pricing) of products during immediately preceding years before deciding to make Table XXVIII. Aerosol Production of Larger Volume Countries Country U.S.A. England West Germany France Japan Italy U.S.S.R. Netherlands Canada Spain Australia Brazil Poland Argentina Venezuela Belgium/Lux. Switzerland Mexico Czechoslavakia Country Austria Yugoslavia East Germany South Africa Greece Formosa (Taiwan) Hungary Rumania Nigeria Portugal Finland Iran Israel New Zealand Norway China Sweden India Indonesia Egypt Denmark 1975 2355 440 457 480 245 176 139 65 137 109 115 85 61 105 32 45 48 45 33 Production (Millior 1978 2231 563 450 412 301 207 198 139 135 130 128 111 97 71 72 51 44 50 47 1979 2398 522 467 419 342 230 235 159 131 156 125 125 105 92 80 61 50 56 50 Production (Million 1978 37 30 28 61 30 21 23 25 22 24 14 14 15 13 15 12 12 9 8 13 9 1979 36 33 33 58 29* 25 25 25 26 30 18 20 16 13 12 12 12 10 10 15 10* l Units) 1980 1981 2163 2198 498 490 462 429 311 252 292 175 130 134* 151 135 101 112 94 84 72 47 71 93 55 i Units) 1980 39 28* 27 18 13 9 14 11 12 13* •Estimated Note: Imports and exports change consumption figures significantly from production figures. introductions. In many cases products in the U.S.A. were first launched in Europe, such as the feminine hygiene spray, and the reverse is also true. On the other hand some aerosol products doing quite well in Europe do not seem to have interested U.S.A. marketers. Examples are foam shampoos and anti-dandruff sprays. Frypan lubricants are very successful in the U.S.A. and Australia, but are rarely seen anywhere else. A listing of countries producing more than ten million aerosols per year is given in Table XXVIII. In most of these countries the rate of aerosol productions has been essentially static over the past several years, indicating saturation. In several, the chloro- fluorocarbon/ozone controversy has caused sharp reductions in volume, such as 26% in Canada, 30% in the U.S.A. and 38% in Scandinavia, measured from the onset of the problem to the non-recession base year of 1979. The greatest increases in volume are now taking place in the developing countries. Mexico increased its aerosol production by 30% from 1978 to 1979. This trend continues into 1980 and 1981, and should be sustained by an economy made more robust by increasing petroleum exports. In Africa, virtually every nation except the Republic of South Africa (which is saturated) is growing fast in aerosol consumption. Omitting South Africa, the continent showed a production increase from 46.4 million in 1978 to 80.5 million in 1979, an advance of 73%. During 1980 this increase continued, although figures are not available at this writing, and large numbers of aerosols were imported from the Netherlands, England and other countries against the time when additional local filling facilities could be constructed. In 1980, Nigeria imported more aerosols than were filled locally, and several smaller African economies did the same. Other important growth areas include the whole of Central and South America, where production rose 22.8% in 1979, and Asia, where aerosols increased by 14.9% in 1979. (Nothing is known of Siberian aerosol production; it may be included in the U.S.S.R. contribution of 210 million units to the European total.) When the growth, static and declining areas are considered, recent worldwide production is suggested as 5.89 billion for 1978, 6.40 billion for 1979 and about 6.52 billion for the recession year of 1980. Production figures for key countries are given for the period 1970 through 1979 in Table XXIX. Those for 1961 through 1970 are provided in the first edition of The Aerosol Handbook and are not repeated here.
Aerosol Marketing Considerations 39 During the period 1970 to 1980 U.S.A. aerosol production dwindled from 55 to 35 % of world figures. This has been laid to the chlorofluorocarbon/ozone issue, with resultant marketer confusion, bad press, lack of aerosol advertising and consumerist activities, as well as the ban on CFCs starting in 1978, but there were other factors as well. Even before the ozone controversy, by 1973, the zenith of U.S.A. production years, the industry produced only 50% of the world total. This was due to saturation. Later on such things as inflation/recession (stagflation) and relatively high prices for aerosols began taking their toll. Marketers turned increasingly to less costly alternates. A comparison of U.S.A. and world aerosol production figures is shown in Figure 12. S 6 •a § ■s o g a 3 * 8 o H P 2 a 1 ——. -__-_ i ^ <^ • --=- --: — --"— SU'l'SS' 1-- S^ "^ ' 1 H U~^ | " " " " si:s.\ss. - _.._ -——3=^^-1 1- ^^^u.s.aT1 rssriz ZSZZZ. -— WORLt as=^ S «•*■=■- 1 Figure 12. World and U.S.A. Aerosol Production Table XXIX World Production of Aerosols - J 970 - 1980 Country West Germany England (U.K.) France Italy Switzerland The Netherlands Sweden Spain Belgium Austria Finland Denmark Norway Ireland (Eire) Portugal Greece Turkey Iceland/Malta/Cypress U.S.S.R. & Satellites Total Europe U.S.A. Canada Japan Australia New Zealand Brazil Argentina Other Latin Amer. Mexico Africa World Total 1970 401 304 254 136 51 90 23 34 39 20 20 13 13 6 4 7 2 1 137 1555 2623 140 194 72 13 33 43 15 19 40 4775 1971 401 349 304 158 57 119 27 48 45 28 21 13 16 12 6 14 2 1 134 1766 2554 152 217 83 17 35 53 17 23 50 5013 1972 412 361 359 173 60 120 20 68 45 29 27 14 18 13 7 17 (3) 0) (175) (1899) 2823 163 237 88 18 39 61 17 32 55 5465 (Millions of Units) 1973 389 438 394 194 58 136 24 99 49 31 29 14 17 22 8 20 (3) (1) (225) (2159) 2902 168 264 105 22 58 64 18 36 73 5910 1974 418 478 450 203 59 155 24 112 46 31 29 14 15 15 9 23 (*) (1) (270) (2353) 2722 182 252 126 26 67 101 20 44 91 6009 1975 425 441 383 173 47 147 19 109 46 33 22 14 13 5 12 22 (5) (2) (320) (2237) 2354 148 220 115 15 85 105 50 65 80 5477 1976 457 495 454 253 50 145 i8 120 51 35 21 13 14 5 20 26 (5) (2) (385) (2566) 2295 149 272 124 13 108 92 71 54 84 5804 1977 454 532 466 192 53 143 13 146 54 38 15 11 13 5 30 28 6 2 429 2633 2150 144 269 121 14 100 70 93 48 132 5773 1978 450 563 412 207 44 139 12 130 52 37 14 9 15 5 32 30 7 2 408 2557 2231 135 301 128 13 111 71 104 50 147 6027 1979 467 522 419 227 50 159 12 156 61 38 18 10 12 6 30 29 7 3 489 2709 2398 135 342 120 13 130 92 132 65 191 6551 1980 462 498 429 252 47 175 11 151 72 39 18 13 9 3 27 28 7 3 528 2771 2165 130 311 135 13 101 94 145 71 208 6144 Note: Figures in parentheses represent best available estimates.
40 The Aerosol Handbook Table XXX Ten Year Variations in U.S.A. Aerosol Categories Category Insect Sprays Coatings and Finishes Household Products Personal Products Animal Products Industrial Products Food Products Automotive Products Miscellaneous Per Cent of the Total Market 1970 4.0 8.8 23.8 52.6 0.4 1.7 3.4 2.2 3.0 1975 4.3 11.8 24.1 45.6 0.6 3.2 6.4 3.3 0.6 1979 5.8 12.8 28.0 33.1 0.8 5.7 6.0 7.1 0.6 1980 6.9 14.3 26.8 29.4 0.7 7.9 6.5 6.0 1.4 During 1980, worldwide use of aerosols was about 1.4 units per capita. If we assume conservatively a population growth of 2 % per year and an increase in usage rate to 1.6 by 1990, world consumption then becomes 8.8 billions, up 42% from the 1980 figure. By referring to Figure 6, where the U.S.A. production is projected to 3.25 billion by 1990, it follows that the domestic contribution will remain about the same, at some 37% of the total. The U.S.A. market has often been considered a trendsetter for markets in other countries. This is only a qualitative thing at best, since production of various products in other lands will inevitably be a composite of climate, regulations, timeliness, public perceptions, backgrounds and other factors. But in general, many countries begin with heavy emphasis on insecticides, then air fresheners and shaving creams, then other personal products plus paints, and finally a strong growth in the automotive and industrial products. It is interesting to look at the U.S.A. aerosol market to see how the aerosol categories have changed during the 1970s, as shown in Table XXX. Strong expansion in the automotive and industrial product categories might suggest these areas for new product introductions. Insecticides are also believed to be a late bloomer. According to Packaged Facts, Inc. 1980 retail sales will be about $324 million and should rise to $660 million retail by 1985. This is due to an alarming rise in insect population, strong advertising, heavy trade promotion and new product introductions. If this is true, insecticides could account for more than 10% of the total U.S.A. aerosol market; something they have not done for over twenty years. The Can Maker's Institute provides their members with monthly survey figures on the number of cans Figure 13. U.S.A. Aerosol Production 1972-1981 a < n ^ i* «£> r. ■■» <a *r .-r. n > X p. m m ? t-< >■ 1 c, m m V, *?. n 2£ P-j n w s »"> 'H <t. ST. <^ sa ir- 'Z. < •w < X a. IS) Ul an rf n rf w 0. M 01 S5 <:£ .-, X s Bt W w < <$
Aerosol Marketing Considerations 41 made and shipped by participating companies. Unfortunately, some of the firms that make aluminum containers exclusively have not contributed their figures, as a result the CMI surveys are consistently about 7.2% lower than actual. When this non-reported quantity is figured in, and the total adjusted to include die small percentage of the industry volume marketed in glass and plastic aerosols, a rather accurate assessment of total U.S.A. aerosol volume emerges. The monthly survey data becomes available about 75 days after the reported month. Allowing a month for shipment to die filler, warehousing of empties by the filler, actual filling, further warehousing and shipment to the marketer or distribution center, it is reasonable to suggest a 45 day time lag in relation to either production of the aerosol or its availability to the marketplace for sale. For a number of years the aerosol business has displayed an interesting cyclical pattern. The peak can- making period is in March, followed by one in October. Very slow months include July and December, probably due to vacation spending and Christimas gift spending as alternates to the purchase of aerosols. The effects of recessions can be clearly seen when these monthly data are graphed. Then in mid-1974 the devastating effects of the chlorofluorocarbon/ozone controversy can be observed, widi production tumbling about 35% to a bottoming point in "black February" of 1976. These data are shown in Figure 13. The Marketplace Most aerosols are sold in supermarkets and mass merchandiser oudets. The rest are sold in drugstores, grocery stores, hardware stores and a variety of otiier retail establishments. The larger stores constandy monitor sales per linear foot of shelf space as well as profitability. It takes an average 27% markup just to operate a supermarket, and tiiese stores will tolerate lower markups only for nationally advertised brands where the customer expects to find them available. The loss leaders are national brand laundry detergents, where me markup is only 10%. Because of the low profit, supermarkets have pushed private label counterparts from less than 1% in 1970 to about an 11% market share in 1981. Supermarkets characterize their products about as follows: a. National brands. b. Private label (PL) products. i. Store name products — such as "Stop & Shop". ii. Franchise brands — such as A&P's "Sail", promoted and advertised by me chains much like a national brand. iii. Buying Co-Ops which joindy buy PL products — such as "Topco", now offered by over twenty chains. iv. Generics c. Regional or local brands. In contrast to most nationally branded products, PL products can generate significant profits for the store. They usually sell for 20 to 30% below the nationals, with generics an additional 10% below that. Store name brands are more or less on a par with the quality of the national brands. They can thus generate consumer loyalty which can grow to overall store loyalty. Private label fillers include Chase Products Co., Georgia-Pacific, Inc., and several others. It is a capital and space intensive business due to inventory requirements. Also, these manufacturers are expected to show supermarkets how to improve meir PL sales. The products need a highly visible position, an adequate price spread and regular advertising support and promotions, such as couponing. The package must have a strong selling message. The generic products were initiated in France, where they now hold over 30% of the big laundry detergent market and several otiiers. They were introduced into die U.S.A. by Jewel Home Shopping Service, Inc., Figure 14. Packaging of Gillette Products in England. Cans are placed in trays then shrink-wrapped in polyethylene. Much of the European aerosol production is shipped in this form. The material for two 211 x 413 can six-packs weighs 20 grams, while an empty 12-pack corrugate (175# burst) case weighs 220 grams, — eleven times as much.
42 The Aerosol Handbook and now hold a 22% share of certain categories. They are increasing fast. Aside from a large 24 Av. oz. aerosol shaving cream product we have not seen any aerosol generics during 1981; however, the aerosol market is not immune from this type of merchandising. Packaging Considerations Good formulations rarely sell themselves. They require expert packaging with careful attention to marketing (and legal) requirements. Fewer than 10% of new products, packages, sizes and so forth are accepted by supermarkets these days. When a buyer or retailer looks at an aerosol, he sees merely another consumer packaged goods item to be evaluated. He wants to hear selling facts. Specifically he wants to see: a. Proof of potential sales volume. b. Profitability. c. Evidence of consumer demand. d. A new and uncomplicated item, free of problems. Proof of potential sales and valid evidence of consumer demand are generally provided to him in terms of test market results. Market studies often show that aerosols have superior sales and profit power, but not always. In terms of such aspects as: a. Total dollar sales. b. Dollar margin. c. Total unit sales. d. Dollar sales per item stocked. e. Average profit per item stocked. f. Unit sales per item stocked. g. Dollar sales per linear foot of shelf space. h. Dollar margin per linear foot of shelf space. Aerosols often outsell non-aerosols, and for this reason have a much improved chance of securing the retailer's valuable shelf space and inventory investment dollar. In matters of package design the average or smaller marketer will work in conjunction with a large advertising agency or specialty house. In a few cases the contract filler will make a major contribution to container and label development. Package design and display are considered the major purchasing inducement for over 25% of customers, and it follows that elaborate plans are developed to show off the package in its best possible form. A check list is often compiled and used to rationalize and organize efforts toward this goal. Marketer's Packaging Check List Product Review a. Is the product new or demonstrably better than others? b. Has an analysis been made of its relative qualities competitively? c. Are the advantages identified over competition? d. Does the packaging choice consider— i. Which package will reach desired markets most effectively? ii. Improved properties that permit shelf life; better distribution? iii. Are additional forms possible to enhance sales? Market Review a. Has the ultimate consumer been determined? (Age — income — sex — race — life habits — interests) b. Has the distribution plan been determined? What channels? (Independents — chains — self-service — mail order — house-to-house) Display Program a. Have retailer buying habits been checked for — i. Unit of purchase? ii. Storage prior to sale? iii. Display on shelf, counter, window, etc.? Mass display? iv. Will package be viewed at, above or below eye level? v. Which panel of display box, shadow box, etc. will be visible? vi. Will there be a point-of-sale display? Size Considerations a. Is size of package adapted to distribution methods, consumer habits and needs? b. Would a change in size affect consumer convenience of quality of purchase? Competition a. Has product been compared to competition, if any? b. Has packaging been compared, as to materials, size, shape, colors and designs?
Aerosol Marketing Considerations 43 c. Is packaging to be distinctive, or should it resemble that of brand leaders? Graphics Review a. Is identity clearly established by — i. Necessary features, properly positioned and emphasized? ii. Printing brand name in unmistakable position, clarity and style? Hi. Is product name featured for instant identification by consumer? iv. Is name of manufacturer presented with adequate prominence? v. Possible link-up with family name, if any? b. Does die packaging indicate— i. Any outstanding qualities of the product? ii. The manufacturer's integrity, sense of responsibility or warranty? iii. Tie-in with advertising programs or slogans? iv. Possibility of useful television promotion? c. Is information presented on— i. Instructions for use? ii. Instructions for secondary uses? iii. Precautionary statements? iv. Formula of product; for economic poisons, drugs, foods, some cosmetics, paints, etc.? v. Illustration panels? vi. Suggested retail pricing? vii. Code marking? viii. All items covered under Federal and local Acts and Regulations? d. Is overall impression good at point of sale? i. Are colors and designs in good taste and appropriate for product? ii. Does package look good from a distance, from close up, on the shelf, in the home, next to competition? iii. Does it carry a self-selling story? iv. Is it adequately visible and appetizing? v. Is recall value high? Distribution Review a. Is package size and shape convenient for wholesaler and retailer? b. Is packaging convenient for storage, stacking, display, sales handling, price marking, checkout and delivery to home? c. Is package designed to expedite self-selection, self- service, quick turnover? d. Does package help solve pilferage problems, soilage, breakage, seasonal and holiday loads and dealer problems with regard to tie-ins and promotions? e. Are contents damaged by freezing or overheating? Use Factors a. Is the size unit the best possible? b. Is pre-sale inspection desired or possible? c. Can package be easily opened and reclosed; cap, actuator dome, child-resistant closure? d. Is label resistant to water damage? e. Can consumer measure out desired amount with reasonable assurance? f. Will package perform under all reasonably forseeable use conditions? g. Is size convenient for consumer storage units? To illustrate the importance of advertising, package design and displays, it has been shown that these attributes were instrumental in influencing 67% of all brand switchers to buy a product that they would normally not have purchased. Figure 15. Translucent 6-Pack Trays Made in England Six-pack 211-diameter and 202-diameter translucent, thin plastic trays used to hold aerosol cans made in Europe and shrink-wrapped with polyethylene film. This cost-saving packaging mode has not yet been approved by the U.S. Department of Transportation. «l «---
44 The Aerosol Handbook It must be remembered that the most effective packages are functional, they get attention at a distance and close by, they excel in recognition power and they must have lasting power beyond the duration of the advertising campaign. Package designers strive to achieve these goals by increasing the apparent size of the unit, giving it high visibility (many shoppers forget their glasses), distinctive design, message organization, color dominance and mass impact, where one plus one should equal more than two. Even such seemingly trivial things as package gloss must be considered. High gloss finishes are preferred by 25 to 1. Gloss conveys such impressions as "the cared- for look" (like a fine car), a safer product (smoothness connotes safety; less suspicion of contamination), the wet look (perceived as recently cleaned and still wet), good complexion (attractive), strength (strong and durable), easy visibility. A glossy surface is also sometimes interpreted as flashy, cheap and utilitarian, so the more expensive products indulge in gloss only on a limited scale; usually for lettering, metallic designs and so forth. Where softness is desired, such as in certain boudoir products, gloss is totally avoided. Colors are immensely important to product success. The most dominant color is puce (color of dried blood), but this has unpleasant overtones, so yellow is more often selected. Generally, yellow is used in moderation because of its brilliance. It is used for "cents-off' bursts and other special applications. Yellow is also applied to specific products, such as sun badiing products. Yellow suggests the sun, blue symbolizes the sea, and bronzes indicate a healthy suntan. Subliminal psychological motivations are a major selling force in this and other markets. Yellows, green-yellows and orange colors are being used often, as aerosol marketers strive for high visibility. These colors are associated with the trend toward lemons, limes, citrus fragrances and so forth, which appear to connote the ultimate in cleanliness. Products designed for the teen-age market often include red, purple on yellow, royal blue on orange, and so forth, because of the younger set's proven affinity for hot colors. White has a clinical appeal, but gold and white combines efficacy with elegance and this combination is used for several high priced, perfumed, after-bath talcum powder sprays. Men's colors include glossy blacks, browns and tans, often embellished with touches of vivid orange and red for style. It should be remembered, however, that women still do much of the buying for men, and are the dominant buyers of men's toiletries. In countries other than the U.S.A., the response to colors may be quite different. For instance, in Japan red is perceived as a brave and manly color, while white signifies craftiness and cunning. Once the finished label design is arrived at, it must be scrutinized carefully by a number of experts, such as the Technical Director (for verification of claims, formulas and use directions), the VP-Sales, Group Product Director and Product Manager (for appeal, position, visibility and so forth) the Packaging Development Director (for technical reproduction, etc.) and the Legal Department (for compliance widi myriad Federal Regulations). After this, the design is submitted to the can company, the glassmaker or the paper label manufacturer for conversion into final form. Preliminary copy, such as canmaker's "black-and-white" proofs, is nearly always sent to the marketer for final review before the production process commences. Cost Considerations in Aerosol Production At the production level the cost of a finished aerosol is made up of three components: a. Concentrate and propellent b. Packaging elements c. Services. Each of these must be developed separately. For the first two categories the net supplier costs are used for the quantity levels required. Reasonable overages are added to compensate for anticipated factory losses. Freight costs must also be figured in where applicable. In the services category are included the cost of direct labor, manufacturing burden, SG&A (Selling, General & Administrative Expenses) and profit. In unusual situations, additional costs may be incurred, such as the need to purchase special equipment, or to inventory finished stock against established minimums. On the other hand, discounts are often provided for cash-with- order or immediate payment of invoices for produced or shipped merchandise. An example can be provided in the case of a 1 lb. hair spray formulation, filled in lots of 100,000 cans per order. a. Cost of concentrate and propellent. Fill weight target is 464.9 g per can (1.025 lb./can)
Aerosol Marketing Considerations 45 Alcohol (anhydrous) AMP Amphomer 28-4910 Isopropyl myristate Methlyene chloride Perfume oil Propellent A-70 $195.19/M. cans (with 3 % loss factor) 5.29/M. cans (with 5% loss factor) 79.89/M. cans (with 5 % loss factor) 1.51/M. cans (with 5 % loss factor) 46.01/M. cans (with 6% loss factor) 11.69/M.cans (with 5% loss factor) 85.35/M. cans (with 12% loss factor) S424.93/M. cans. b. Cost of packaging elements. Can (211x713) lithographed $319.65/M. cans (with 1.5% loss factor) Valve with actuator 44.83M. cans (with 1.5% loss factor) Cap - one-inch - white 8.74M. cans (with 1.0% loss factor) Case-12pack 14.17/M. cans (with 1.0% loss factor) Glue & miscellaneous 1.03/M. cans c. Services. Direct labor Manufacturing burden SG&A Desired profit S388.42/M. cans. $16.00/M.cans 32.00/M. cans 4.00/M. cans variable S52.00/M. cans, plus desired profit The Factory Cost is thus: $861.35/M. cans, and The Sales Price is thus: $865.35/M. cans, plus desired profit. This cost development system is fairly standard for the U.S.A. In Europe and certain other areas the method of calculation is quite different, and more complicated. In the above example, if the marketer purchases the 100,000 hair spray units for $930.00/M. including freight to his distribution centers, he will then charge his distributors from about $1000.00/M. (lots of 1000 Table XXXI. Advantages of the Aerosol Dispensing System 1. Product cannot evaporate. 2. Product cannot become contaminated with bacteria, dust and so forth. 3. Product cannot spill if package is overturned. 4. Highly colored, alkaline or chemically active products can be delivered without contacting the body. 5. Product is ready for instant use at any time. No heating or thawing, no screw-caps to undo, no mixing, blending or measuring. 6. Product can be applied to surfaces cleanly and evenly. 7. No extra items are needed, such as a paintbrush, bucket, rags, cleaner and so forth in the case of paint products. 8. Products have very long shelf lives — 3 to 30 years. 9. Dispensers are portable, easily stored. 10. Metering spray valves give automatic portioning or dosages if desired. 11. Very small amounts can be dispensed — down to about 50 mg. 12. Extremely fine mists can be produced, for instance, to make insecticides much more active. 13. Product characteristics will not change under extended storage. 14. Sprays can be used to penetrate cracks and crevices — to lubricate, undercoat, kill insects hiding between walls, and so forth. 15. Provides a unique and desired dispensing method, as in hair sprays or foams. 16. Can safely contain and dispense noxious chemicals, such as "Mace". 17. Can dispense powders, liquids, gases, gels, foams, dispersions, pastes and other product forms with equal facility. 18. Sealed system prevents oxidation of delicate chemicals, such as some perfumes. 19. No skills or tools are required to operate. 20. Dispenser will not break or shatter if dropped. 21. Can perform unusual feats — such as killing wasps and hornets in their nests at distances of fifteen feet (5 m) or more. 22. Automatically stops dispensing when valve is released. 23. Are eminently safe when used as directed and have a good safety record. 24. Are often less expensive than competitive products.
46 The Aerosol Handbook Table XXXII. Disadvantages of the Aerosol Dispensing System 1. Users may inhale aerosol mists, sometimes irritating, as in the case of antiperspirants. 2. Package may overpressurize and rupture if heated to about 155° to 220°F (60°C to 105°C), depending upon formula and dispenser. 3. Some aerosols are flammable — could cause hazards if used contrary to label directions. 4. Some persons object to insecticidal odors, as dispensed by some aerosol insecticides. 5. Directionality of the spray may be a problem for some actuators. 6. Clogging or sustained streaming may occur for paints, coatings, starch sprays and so forth, especially if label directions are not followed. 7. In rare instances (less than one can per thousand) aerosols may depressurize as a result of slow propellent leakage and become inoperative. 8. Relatively high expense as a packaging system. 9. The term "aerosol" is limiting, reminding users of bad press on the chloroflurocarbon/ozone controversy and consumerist issues. 10. Disposal of aerosols is perceived as a possible problem. 11. Higher than average energy consumption is needed to produce the can — especially aluminum cans — and hydrocarbon propellents represent an energy source that could be used for heating or other applications. 12. With minor exceptions all containers are cylindrical in shape. 13. Aerosols may dispense gaseous and/or liquid hydrocarbon products into the air (estimated at 15,000 pounds, or 7,000 kg, per day in the Greater Los Angeles Metropolitan area, for example) and thus come under strong criticism from the "Clean Air" advocates in areas sensitive to smog problems. 14. Can be used to produce psychodelic highs and to generate graffiti, as is the case with a number of other products as well. cases) to $1300.00/M. (lots of 11 cases or less). The distributor will then establish a salon or wholesale store cost of about $1.80/can, and after that the markup to retail will normally* be at least 30%, or $2.34/can. The Aerosol Advantage Despite the relatively high cost in some instances, the aerosol dispensing form has a large number of advantages, and no marketing survey would be complete without considering them. A listing is given as Table XXXI. It is not represented as complete, and the advantages do not apply to every aerosol. Nevertheless, it remains as a useful guideline. On balance, it is only fair to comment that there are several disadvantages to the aerosol dispensing system, and a number of these are described in Table XXXII. It is interesting to note that the industry has long considered explosions and flammability to be the major hazards of the aerosol system. However, the consumer discounts these and worries mostly about inhalation and possible toxicological sequellae. His rationale? He can control and eliminate flammability and bursting with reasonable care, but he cannot escape inhaling, eventually, those aerosols sprayed in the house. In this chapter we have provided many of the essential considerations of the marketing process; an immensely complex route from product concept to the emergence of the finished aerosol in over 100,000 retail outlets throughout the country. Corporate profits, in some cases even corporate existence, often hang on marketing decisions made with never enough data, but with gaps filled in by experts using educated guesswork born of experience.
47 THE TECHNOLOGY OF METAL AEROSOL CONTAINERS 2 The first true aerosols were developed by the inventor Eric Rotheim of Oslo, Norway in about 1922. He used heavy-walled brass shells, brazed together at the center, as the container. He added the aerosol concentrate to the "bomb" through a small hole in the top, screwed a primitive aerosol valve into the hole and added propellent to the formula by forcing it backwards, through the valve and into the can. Isobutane, vinyl chloride and carbon dioxide were used as propellents. The chlorofluorocarbon gases had not yet been discovered by the I.E. duPont de Nemours & Co. Inc. About 1972, one of Rotheim's original cans was spray- tested in Oslo by Dr. Hroar Hafel of the Norwegian Aerosol Association. It worked perfectly, after over fifty years. Although Rotheim patented his developments, practically nothing was done with the aerosol concept until 1943 when two USDA researchers, Lyle Goodhue and William Sullivan, were asked to develop an insecticide "bomb" to assist U.S.A. troops in coping with severe mosquito problems in various South Pacific islands. They eventually produced very effective insecticide formulas consisting of about 10% oil-based pyrethrums concentrate, plus 90% P-12 (dichlorodifluoromethane) as the propellent. They tested this mixture in containers made of 0.0444 "(1.1 mm) sheet steel by Westinghouse, of a size sufficient to hold one pound of product. Between the years 1943 and 1947 over 30 million of these dispensers were produced and during this time they found acceptance in the civilian marketplace. The high cost of these returnable steel cans prompted both the Continental Can Co. and the Crown Can Division to see if they could produce a lightweight disposable container, patterned after their existing beer cans but of heavier construction. Teams led by Harry E. Peterson and Earl Graham, completed these projects in 1946. In the following year both the Continental Can Co. and
48 The Aerosol Handbook Table II Major Aerosol Can Suppliers in The U.S.A. Xtir Figure 1. Modern and Original "Spra-tainer" Modern version of the original "Spra-tainer" (showing necked in shell and stronger dome profile), compared with the original 6 oz. and 12 oz. "Spra-tainers" introduced in the late 1940s by Crown Cork & Seal Company. The center can is lithographed for NAIR Hair Remover Foam (6 oz. fill). Bridgeport Brass Co. developed the capability for mass- producing aerosol valves of a dramatically improved type. Inspired by the commercial potential of the aerosol system, Harry Peterson left the Continental Can Co. to help form the Continental Filling Corp. in Danville, IL, which was probably the first strictly contract filler of this new breed of products. The industry as we know it today, was launched in Danville, IL in Feb. 1948. For several years the only available cans were the 12 fi. oz. "Spra-tainer", a two-piece unit by Crown Can Division, and a very slightly larger three-piece unit by Continental Can Co. with concave ends. Both required a hand-soldered valve assembly until late 1949, when Crown Can Division developed the now familiar one- inch valve cup which can be hermetically sealed onto a specially designed, beaded can opening by a process known as crimping, also (incorrectly) clinching, and (later on, in England) swaging. In 1951 the smaller 6 fi. oz. containers wre developed in both two-piece and three-piece styles. Continental Can Co. then introduced a 14 fi. oz. can in 1954 and after this came a whole parade of tinplate and aluminum can sizes. Now there are perhaps as many as forty sizes and shapes to choose from. Table I. Market Share of Aerosol Containers Construction Tinplated Steel — All Kinds Tin-Free Steel - as C/CO Plate Aluminum — All Kinds Glass — Plain and Coated Plastic Stainless Steel Market Share* 73.2 16.2 8.5 1.9 0.1 0.1 Corporate Name Industry Name or Acronym American Can Company Continental Can U.S.A. (Continental Can Group, Inc.) Crown Can Division (Crown Cork & Seal Company) Heekin Can Division (Diamond International Corp.) National Can Corporation Sherwin-Williams Company Southern Can Company Canco or ACC Continental or CCC Crown or CC&S Heekin National or NCC Sherwin-Williams Southern or SCC •During 1980 and 1981. Steel and Tinplate Containers In the U.S.A. the tinplated aerosol can is the preferred packaging medium for most aerosols. It comes in a large variety of sizes and currently enjoys a rather stable 73% share of the market. The market share of various container types is shown in Table I. These shares are very different for countries other than the U.S.A. For instance, about 90% of Canadian aerosols are tinplate cans manufactured by Crown Cork & Seal Co., in Toronto. In Australia the market breaks down to about 95 million tinplate cans (88% by Containers, Ltd., and 12% by National Can, Ltd.), 6 million aluminum cans and 500,000 glass units. In India almost 100% of the market is aluminum—the only kind produced domestically. In England tinplate cans enjoy about 80% of the total market, supplied by Metal Box Ltd. (70%) Crown Cork & Seal Co. (25%) and Huntley, Boorne & Stevens Ltd. (5%). In mainland Europe the division between tinplate and aluminum is about 60:40 but varies according to country. Mexico is about 85% tinplate, 10% aluminum and 5% glass. There are seven major steel and tinplate aerosol can suppliers in the U.S.A., shown in Table II. Very small market shares are held by the Bridgeport Metal Goods Manufacturing Co. (returnable medium size steel), Tube Manifold Corp. (very large steel aerosols) and Shield Chemical Co. (202 x 509 size tin- plate). Together these ten can manufacturers share a market estimated at 2.13 billion cans, or $320 million in 1979, or about 1.93 billion cans, or $325 million in 1980. Crown Can Division is considered to have the largest market share. During the period of 1967 to 1981, the National Can Corp. owned and operated the Apache Can Division,
The Technology of Metal Aerosol Containers 49 first making both tinplate and aluminum drawn-and- ironed aerosol cans in several sizes, but later restricting themselves to a few tinplate sizes. Competitive pressure from a 202-diameter double necked-in welded can drove the Apache Can Division out of business. These sophisticated containers are now lost to the industry. In one instance a special 211x713 can with 165# 207.5-diameter dome was shown to be capable of withstanding 460 psig (3.17 MPa) before bursting, which is 50 to 100% higher than the industry averages for tinplate aerosol cans. The primary aim of all can suppliers is to make high performance cans at minimum cost. In this case, they start with a low carbon steel plate that has been rolled to a specific thickness ranging from 0.006" to 0.016 " (0.15 to 0.41 mm), except for the still heavier plate used for the drawn "Spra-tainers". Usually, the chemistry of the steel can be described as Type MR, (Minimum Residuals), meaning low in carbon, sulfur and phosphorus. Other steel compositions are sometimes used, such as Type D, which always contains aluminum, and Type L, which is uniquely low in both metalloids and copper, but these types have restricted applications and are not nearly as popular as Type MR, the industry standard. Type D aluminum-killed plate is used by some can companies for deep-drawn can domes, since it is more ductile and fabricates better than other types of steel. As the finished steel emerges from the open hearth furnace or the Basic Oxygen Furnace (B.O.F.) it is most commonly poured into ingots about 24 " x 24" x 72" (610 x 610 x 1,830 mm) which are then hot rolled into slabs and finally into plate. A newer and more sophisticated method is now gaining popularity: the continuous casting process, where the molten steel leaves the open hearth or B.O.F. mold as a liquid slab about 12" (305 mm) thick by 36 "(915 mm) wide. As it drops, it is cooled and solidifies as a long, curving slab which is cut to desired lengths. The slab is then rolled to a prescribed plate thickness. Plate made by the continuous cast process has a more uniform grain structure and is more homogeneous in its properties. The method used in the preparation of steel plate contributes to the final properties of the aerosol can, and the canmakers make their material selections accordingly. Two basic kinds of plate are produced: single reduced and double reduced. To make the first, the steel slab is rolled to the desired final thickness, then annealed, cleaned and either tin or chrome-chrome oxide electroplated. To make the increasingly popular double reduced plate, the steel is rolled to a thickness of 10 to 100% greater than the final desired dimension. The plate is annealed and then given a final cold reduction: rolling it to the desired thickness. After this step it is cleaned and electroplated in the same fashion as single reduced plate. Double reduced, or 2CR plate (twice cold rolled) as it is called, is often used for can bodies. The work hardening that is produced by the second rolling makes for a relatively britde plate with very distinct directional properties. Can companies take advantage of each type of plate for specific can making operations. Single reduced plate is a requirement for aerosol can ends. Double reduced plate is required for Continental Can Co.'s Conoweld (electro- forge welded) side seam cans, because the process works best with this variety. Annealing is performed using either a box (or batch) process or a continuous one. In the box mediod, coils of plate are stacked in a large oven and thermally treated in a controlled atmosphere for about three to five days. In continuous annealing, the coil of plate is unrolled into a very long vertical oven in which heating and cooling is performed in various zones at pass-through rates of about 2500 to 4000 feet per minute (760 to 1200 m/min.). Continuous annealing provides closer and more exacting control of time and temperature, resulting in a plate of more uniform properties. The annealing step can be used to produce plate with a variety of tempers, depending on operating conditions. After cleaning, the annealed plate is electroplated, with tin. Until the mid-1970s at least some plate was tinned by the hot-dip process, but this was abandoned due to cost factors and the relative non-uniformity of the tin thickness from one location to another. Pure tin is the most common material plated onto the base steel. The product is then called electrolytic tin- plate, or ETP. A second process is to electroplate a very thin coating of chromium and chrome oxide on the base steel. This plate is known as electrolytic chrome coated steel, or ECCS. It is more commonly referred to as C/CO plate or TFS (tin free steel). In the tin plating mill the plate is unrolled from the coil, cleaned of oxidation products and then given an inorganic phosphate chemical treatment designed to improve the bonding of the plating material to the base steel surface. The strip is then submerged in a long electroplating bath, where tin metal is transferred from pure tin anodes to the steel in a strictly controlled operation. Conditions are used which tend to maximize the production of a highly resistant intermediate layer of
50 The Aerosol Handbook (mainly) FeSn2 alloy between the steel base and surface tin coating, such as free flame melting of the tinplated surface deposition after the plate is removed from the bath, washed and dried. Flaming also produces a smoother and brighter tin surface, with greater resistance to corrosion because of the reduced surface area. As a final step, the tinplate is passed through a warm sodium dichromate solution in a process known as "cathodic dichromate treatment". An electric current acts to deposit an exceedingly thin film of chromium and chrome oxide (about 4 to 5 micrograms per square inch, e.g. 0.7 fig/cm2) onto the plate. This produces a change in surface properties which promotes adhesion of can enamels and also inhibits the oxidative yellowing of the tin, if left bare. A stylized cross-section of #100 ETP is shown as Figure 2, indicating the alloy layers. Typical #25 ETP (also called quarter-pound or .25# plate) has a quarter of a pound (114 g) of tin coated onto both sides of the standard base box area of steel plate. A base box is a historical term that is still a U.S.A. standard reference area. It consists of the area of 112 sheets measuring 14" x 20" (356x508 mm), or in other words, 31,360 square inches, 217.78 square feet or 20.25 m2. The equivalent thickness of the tin coating is thus about 0.000022" (560 nm) total, or about 0.00001" (280 nm) on each side. Figure 2. Cross-Section of #100 ETP, Showing Layers of Tin and Intermetallic Compound Figure 3. Dimensions of a Cross-Section of 85# Base Plate with #100/25 Differential Tinplate Tinplate thicknesses are expressed as theoretical thickness, not considering FeSn2 alloy formation. The diagram is not to scale. Most aerosol cans are made from #25 EPT, but where product compatibility problems require heavier tin coatings they can be made available on reasonable notice. A #50 ETP can be used, as well as the #50/25 and #100/25 differentially coated plates. On these last two there is a different weight or thickness of tin on each side. The heavier tinplate is normally turned toward the product, to provide increased mechanical and electrochemical protection. Figure 2 depicts a cross-section of a typical 85# base weight plate with a dual or differential #100/25 tinplated surface. During 1982 two new, extra-thin tinplates were introduced, #10 ETP and #10/20 ETP, for cost-saving purposes. The #10 ETP surface is actually so thin that the dark grey steel and alloy layer can be seen through it. On the differential #10/20 ETP plate the suppliers often recommend turning the thin side toward the product, to keep the end-sections from looking dull grey. Depending on can size and plate selection the savings can be as much as about $2.00/M. The usual #25 ETP, now used on well over 90% of all tinplated aerosol cans, is produced by modern techniques which control tin thickness, the alloy layer, grain structure and other factors to a remarkable degree. Because of this it will offer virtually the same degree of electrochemical protection to the steel as will any of the much more expensive tinplates, except where tin may be required as a sacrificial metal in the corrosion process. The final product of the steel mill is coils of tinplate or ECCS having a thickness of from 0.006" to 0.016" (0.15 to 0.41 mm) and a range of widths from 24" to 40 " (610 to 1020 mm). The coils run some five to six feet (1.5 to 1.8 m) in diameter and weigh between 30,000 and 40,000 lbs. (13.6 and 18.1 Mg). A 12 " (305 mm) core is provided for handling and unreeling purposes. The steel company may ship coils to the can company, or occasionally first cut the coiled stock into sheets, which are then stacked and wrapped for shipment. The performance aspects of aerosol cans relate to structural strength, corrosion resistance, lithographic quality and several other parameters. Considering structural strength, at least five factors" apply, and the canmakers must engineer and design their production equipment accordingly. See Table III. There are also several other less important factors. For instance, the application of the valve cup (considered as a secondary end by the canmaker) may deform the dome sufficiently to reduce pressure resistance. Dents and nicks on can ends may also reduce
The Technology of Metal Aerosol Containers 51 Table III Factors Influencing The Structural Strength of Aerosol Cans Factor Degree of Canmaker Control Unit profile. (Specific shape or configuration) Plate thickness. Temper. Steel chemistry. Processing temperature (Hot-tank) Complete. The canmaker has total control over the thickness specification selected, but no control over the variability of this plate as received from the mill. The canmaker has total control over the temper specification selected, but no control over variability from the steel mill. Canmaker has total control over selection from those alloys available, but no control over variability from the steel mill. None. The can filler has total control over hot tank temperature and residence time, within equipment limitations. Temperature has a minor effect on strength of domes. Cans may lose 7 to 10 psi. (48 to 68 kPa) of buckle resistance when the temperature is raised from 70° to 130°F (21° to 54°C). strength, depending on exactly where they occur. As a rough approximation, those close to the center panel may reduce resistance from 270 psig. to 235 psig. (0.020" dent) or even to 140 psig. (0.100" dent). A dent on the can body does not change the pressure capability of the can, but it may reduce vacuum resistance at the time of vacuum crimping, possibly leading to can collapse. This is an important factor in the case of the new extra-thin double-reduced bodies. A major consideration affecting structural strength is the actual thickness of the plate used to fabricate the container. The nominal thickness is indicated by the Table IV Thickness of Tinplate Used In Aerosol Cans Weight per Base Box Pounds 65* 70* 71 75 80 81 85* 90* 95* 100* 107 112 118 123 128 135 Thickness (Minimum) Inches 0.0065 0.0069 0.0070 0.0074 0.0079 0.0080 0.0085 0.0089 0.0094 0.0099 0.0106 0.0111 0.0117 0.0122 0.0127 0.0134 Thickness (Average) Inches 0.0072 0.0077 0.0078 0.0083 0.0088 0.0089 0.0094 0.0099 0.0105 0.0110 0.0118 0.0123 0.0130 0.0135 0.0141 0.0149 Thickness (Maximum) Inches 0.0079 0.0085 0.0086 0.0091 0.0097 0.0098 0.0103 0.0109 0.0115 0.0121 0.0129 0.0136 0.0143 0.0149 0.0155 0.0163 "basis weight" or base weight, the weight in pounds of a standard plate area called the base box. As mentioned earlier, this is the area of 112 sheets measuring 14"x20" (356x508 mm), or 31,360 square inches, 217.78 square feet or 20.25 m2. In the U.S.A., at least 16 base weights are used in making aerosol cans. Their dimensions are shown in Table IV. Plate as light as 55 lb. (made only in double reduced form) and as heavy as 165 lb. (for domes) has been used in the preparation of sample runs of aerosol cans, but not yet on any commercial applications. Cans with very light weight bodies cannot be effectively vacuum crimped. As the steel strip passes through the rolling mill stands the individual rollers bend in the center ever so slightly. The displacement is measured in 0.0001" units (2.8/tm units), but this causes the strip to be slightly thicker in the center area than along the edges. During rolling, electronic measurements are taken continuously and entered into servo-feedback equipment for automatic correction of out-of-specification episodes. But even so, the standard tolerance for U.S.A. plate is Table V Variation of Tinplate Thickness (14 Baseweights) Locus of Measurement Tinplate Thickness (9200 Readings) Below -10% Above + 10% Minimum Maximum Centerline of tinplate coil 1 (0.01%) 14 (0.15%) One inch in from edge 10 (0.11%) 5 (0.05%) *PIate available as either single reduced or double reduced. The data were adjusted for apparent wild readings.
52 The Aerosol Handbook 1 M ■ -ONE INCH FROM EDGE LOCATION — 1/4 INCH FROM = EDGE LOCATIO / s* \ / / , s\ i t i \ • \ \\ i v I) i \! / J 1 CENTER LOCATIC \ i V * \ \ 1' \ 1 V 1 >VJ | I PLATE VARIATION FROM TARGET THICKNESS (") Figure 4. ASTM (Sub. XX) Plate Thickness Survey Single reduced, 100# to 135# base weight. ±10% of the thickness, figured at the three sigma (99.69%) confidence level. In England the standard tolerance is ±8%, also at three sigma. Figure 4 illustrates the variability of thickness at three points on the strip: the center, one inch (25 mm) from the edge, and 0.25 inch (6 mm) from the edge. See Table V. As a rule, the thinner the plate the narrower the spread of thicknesses; E.g., the difference between minimum and maximum thickness. From a practical standpoint, the percentage spread is more uniform, generally ranging 2 to 5% from the nominal base weight and not greatly affected by plate thickness. This is shown in Table VI. Table VI Variation of Baseweight Thickness at Different Locations (14,000 Readings.) Baseweight Thickness (Pound) Nominal % -Variance Baseweight Y* " From Edge 1" From Edge At Center % " To Center S.R. 60 1b. 65 70 75 80 85 90 95 100 107 112 118 128 135 D.R. 55 1b. 60 85 90 95 100 58.6 64.0 67.8 71.8 76.6 81.9 87.0 91.2 96.8 101.9 107.6 113.0 123.6 128.1 54.0 59.3 82.5 89.7 93.1 98.6 59.9 65.5 69.7 73.8 78.9 83.9 89.2 93.9 99.1 104.7 110.5 115.2 127.5 130.6 55.1 60.4 83.6 91.9 95.0 100.3 60.9 66.5 71.4 75.5 80.4 85.4 91.0 95.5 101.0 107.0 112.7 117.0 129.4 131.9 55.1 61.4 85.2 93.5 97.1 102.5 3.8 3.8 5.1 4.9 4.8 4.1 4.4 4.5 4.2 4.6 4.6 3.4 4.5 2.8 2.0 3.5 3.2 4.2 4.2 3.9 S.R. stands for Single Reduced plate and D.R. stands for Double Reduced or "2CR" plate. The minimum thickness for a given base weight has considerable significance. Minimum thickness plate generally has the lowest strength for a given base weight. Can ends and bodies must be designed to perform satisfactorily at the minimum thickness or strength level. Aerosol cans are produced to three levels of pressure resistance in the U.S.A., in order to conform to the Table VII D. 0. T. Requirements For Metal Aerosol Containers DOT Specification Non-Spec" (2N) 2P 2Q Minimum Metal Thickness (Inches) (None) 0.007 0.008 (Mm) (None) 178 203 Minimum Pressure Resistance Without Burst (psig) 210 240 270 Maximum Product Pressure (psig at 130°F.) 140* 160 180 "Equivalent to 965 kPa at 54.5°C in the SI system.
The Technology of Metal Aerosol Containers 53 Department of Transportation (DOT) requirements. They are identified as "non-specification" (technically DOT Specification 2N), DOT Specification 2P and DOT Specification 2Q_ containers. The "non-specification" can must simply meet the minimum burst requirement of 210 psig (1.45 MPa) and aerosol products put into it must not have pressures greater than 140 psig at 130°F (965 kPa at 54.5 °C). DOT Specifications 2P and 2Q_ impose minimum metal thicknesses as well as minimum bursting strength and maximum product pressure limitations. These are summarized in Table VII. It should be noted that 70# base weight usually used for' 'non-specification'' cans fails to meet the minimum plate thickness requirement of DOT Specification 2P perhaps 0.1 % of the time. Because of this, when DOT Specification 2P cans are made, the can manufacturer must either use a base weight heavier than 70# (some use 71# for the body plate) or else cull out the lower end of 70# plate to insure that plate thinner than 0.007 "(178 /an) is never used. A similar situation is in effect for DOT Specifications 2Q_ cans, where 80# base weight stock does not quite fulfill the requirement of an 0.008" (203 fim) minimum thickness. Aerosol containers exported to certain foreign countries must often meet certain size and design standards for those countries. For instance, in Japan containers must have a minimum 0.008" (203 /an) metal thickness and also meet certain pressure requirements without permanent distortion. Exporters should check carefully regulations to insure against possible rejection of filled stock at the customs inspection area. Regardless of the final equilibrium pressure-temperature profile of the aerosol formulation, certain filling operations may cause a momentary to temporary rise in the internal pressure to levels where all but the strongest can bottoms may evert or buckle. The injection of warm propane and the "impact gassing" of carbon dioxide or nitrogen are examples of operations causing a momentary pressure peak. The gassing and shaking of either chlorofluorocarbon or hydrocarbon propelled polyurethane foam products causes a dimerization that will raise the temperature by about 55°F (30°C) maximum — depending on formula — and thus provide a concurrent pressure surge, lasting until the reaction ceases and the dispenser cools. Cans used in such operations must have the equivalent of 2P or 2Q_ constructions, although they need not be tested statistically to destruction by the canmaker, as is the case for cans having official 2P and 2Q_ specifications, where one can per 25,000 must be tested. The end base weight of both unofficial and official 2P and 2Q_ containers often will be heavier than that of standard cans. As one exception, if a special temper or special highly resistant profile is used, then some reduction of base weight may be possible. The data in Table VIII illustrate the buckle resistance of a specially contoured can bottom. The concept of minimum baseweight is also important during hot-tanking, a production step mandated by the DOT for most aerosol products. The finished units are passed through a stainless steel trough up to 35 feet long, containing water heated to about 135° to 165°F (57° to 74°C), with the object of causing the temperature of the contents to rise until the pressure becomes at least equal to the equilibrium pressure in the can when the contents are at 130°F (54.5°C), without permanent distortion. Ancillary benefits of hot-tanking include leak detection (as gas bubbles), cleaning off most product residues and dirt, and even providing a warmed metal surface to facilitate more efficient paper label application. The DOT testing regulation is satisfied if the pressure of the contents reaches the equilibrium 130°F Table VIII Buckle Resistance of Typical 211-Diameter Can Bottoms Criteria 128# T5 Baseweight and Temper 118#T5 118#T4(Dual*) Baseweight Range Tested Buckle (Minimum) (psig) Buckle (Average) (psig) Buckle (Maximum) (psig) 115 to 141# 190 245 285 106 to 130# 160 200 250 106 to 130# 250 310 360 *A special, dual-radius*profile bottom, developed by several can companies during the 1975 to 1978 period.
54 The Aerosol Handbook (54.5°C) pressure, even if only for a moment, without can distortion. This will occasionally happen prior to hot-tanking, as in "impact gassing", gasser-shaking or the injection of warm, higher pressure propellents, such as propane A-108, the propane/P-152a azeotrope, or Aeropin 85 and other propane-rich hydrocarbon blends. Or it may happen as the result of an exothermic physical or chemical reaction in the can, as with the polyurethane foam formula mentioned earlier. Hot- tanking is not a legal requirement in such cases. In fact, when high-pressure propellents are added to concentrates that cannot assimilate them readily, due to viscosity, an oil-in-water (o/w) emulsion system or other factors, then it is appropriate to cool-tank or warm-tank the product, since the heating of a can already under high pressure might cause permanent distortion or even rupture. An alternate method is to either hand shake or mechanically shake these cans, so that the propellent dissolves or disperses into the product, causing a suppression of the pressure so that hot- tanking may be feasible. The use of more pressure- resistant ends can act to provide more latitude and an inherently safer production operation in those instances where higher pressure propellents are used. Finally, baseweight thickness is important as a determinant of what will happen when a can is dropped. The most critical drop is when a can lands vertically upon a hard surface. The momenta! effect of the instantaneous transition of the liquid from vj to vf = 0 (plus other effects) serves to add a force equivalent to a considerable downward pressure factor against the can bottom, often inverting it. For example, cans under 100 psig (690 kPa) pressure and greater than 202-diameter will often invert when dropped perpendicularly onto a hard floor from a height of three feet (914 mm) or more, unless the bottom plate is extra strong. A drop from this distance with the can at a 45° angle is far less discriminating. Under DOT Exemption No. 7951, certain whipped cream aerosols are now being gassed at 40°F (4.5°C) and a charging pressure of 150 psig (1.034 MPa) of CO2 and/or N20 propellent. The cans are DOT Specification 2P and the dome has a venting device. If these cans are dropped off the conveyer after charging and land squarely, there is always base eversion and also about a 1 % chance of a dangerous can rupture situation. The cans are both 211- and 300-diameter with a 123# TU base. The can manufacturer is now investigating at a 128# TU base (normally used with 211-diameter DOT Specification 2Q_cans) as a partial remedy — at least for the bursting problem. Significantly, this bursting phenomenon will not occur under consumer use conditions, since the pressure slowly subsides to about 95 psig. (655 kPa) when the can is stored at 40°F (4.5°C) for a day or two. At this lower pressure a severe drop may cause bottom eversion of the larger filled cans, but not ruptures. Temper The temper (or stiffness) of steel plate is another extremely important consideration. In fact, it is impossible to do more than roughly describe tinplate or C/CO plate without designating this intrinsic property. Table IX Temper Specifications For Steel Plate Temper Designation Rockwell 30-T Hardness 46-52 50-60 54-60 57 - 60* 58-64 62-68 67-73 Rolling Treatment Single (hot) reduced Single (hot) reduced Single (hot) reduced Single (hot) reduced Single (hot) reduced Single (hot) reduced Single (hot) reduced Annealing Treatment Box Box Box Continuous Box Box Box Tl T2 T3 TU T4 T5 T6 DR7, DR8&DR9** >75* Double (cold) reduced** (None) •Metal grain and other differences make TU plate readings inconsistant with those of Tl through T6 steels. Also, the tester cannot be meaningfully used for DR plate; it perforates the material instead of indenting it. *DR9 (and DR9 Special) are still experimental for aerosol applications. Strength is measured as minimum yield; typically 90,000 psi (621 MPa) with a 0.2% offset in the longitudinal direction. *2CR plate. Reduced to one-half the original hot rolled thickness by cold rolling.
The Technology of Metal Aerosol Containers 55 At least ten levels of temper have been described for steel plate alone, as shown in Table IX. The softest plate used in canmaking is Type D steel, available in DTI and DT2 tempers. Such steels are described as aluminum-killed, from the technique of adding granular aluminum metal to the molten ingot to provide quick chilling and the development of small crystal size and correspondingly high ductility. U.S. Steel makes an equivalent product; their "Riband Steel," quenched with a special silicon material. When these drawing steels are made by continuous casting, the initial slab is quick chilled by physical means enroute to the hot rolling state. These steels are particularly well suited for deep draw and draw-plus-redraw operations, such as the fabrication of can domes, without the fracturing problems which might occur with harder plate. They allow the production of high contour domes (as in the 207.5-diameter cans) with deep countersinks and smooth buckle resistant surfaces. The deep draw "Spra-tainer" shells are made from DTI plate with an initial thickness of about 0.0172" (0.437 mm). During drawing, the thickness is reduced to about half and the plate is work-hardened to a temper equivalent of about T5. Because there is essentially no work-hardening of soldered or welded can bodies, higher temper steels are preferred for their construction. Temper hardness is only limited by the increasing possibility of double seam flange splits and by tear-dropping or fluting: the problem of producing an essentially smooth cylindrical profile for side seaming operations. By using DR8 plate instead of TU plate, body wall thickness can be reduced by about one base weight. On the same theme, 75# MRT3, 75# MRT4 and 65# DR8 are all about equal from a paneling resistance standpoint. Actually, the pressure resistance of the body does not involve the ability of the broad area of the can body to withstand internal pressure excesses; the body plate is extremely strong in this respect. Body-ripping is seen occasionally in burst cans, but rarely in those where the body has not previously been softened by contact with fire. Body pressure resistance relates specifically to the stiffness of the body hook, and particularly the ability of this area to help prevent physical separation of everted domes or bottoms during a pressure overload. Because of work-hardening the effective temper in the bent (180° return) hook area can be considered as probably T6 or higher. A final but very important attribute of stiff body plate is that it is less prone to denting as a result of normal can handling operations. This provides a higher quality aerosol can to the customer. Figure 4 shows a cross-section of a typical bottom double seam, with a few of the more critical dimensions. End Unit Construction A wide variety of base weights and tempers are used for the end units of aerosol cans. End base weights are selected according to can diameter, desired pressure resistance, profile or geometry reinforcement effects, metal chemistry and other factors. Despite the fact that they are about 40 to 80% heavier than the body plates, the end units are always the first to deform under excessive internal pressure. One can maker produces top ends that are always weaker than the can bottoms. Pressure curves (against time) taken with transducers show that the pressure in the can will drop momentarily about 5 to 7 psi (35 to 48 kPa) upon dome eversion, then go back up again. This is merely due to the increase in can volume when the end inverts. All the can companies have the ability to make bottoms a great deal stronger than the domes, but there is no reason, design, performance or economic, for doing so. Can domes are made from plate in the 112 to 135# range, with tempers from DT2 to T5. The 202-dia- meter cans use 112# plate as a rule, while the 300-dia- meter can is fitted with nothing less than 135# domes. Probably the strongest of the 300-diameter cans is the one with a 135# T4 dome for DOT Specification 2P 0.0«7" - typical Figure 5. Typical Bottom Double Seam Profile Double seam compound is not illustrated
56 The Aerosol Handbook uses. It usually has a special profile, including a deeper countersink (chime) depth, giving it a 170 psig (1.17 MPa) minimum buckle. (Actually in the 185 to 195 psig range for production units measured at room temperatures.) Plate used for can domes is usually in the T3 or T4 area, but during the die forming of the end, work- hardening occurs and it is difficult if not impossible to relate temper measurement on the formed ends back to the initial temper of the raw plate. The can curl or bead area probably has the highest temper of all, simply because it has been work-hardened the most. In fact, the use of plate that has too high a temper rating to start with will probably result in a cracking phenomenon known as split curls or split beads. This is the area where the aerosol valve cup is sealed onto the can's one- inch (25.4 mm) opening, so that a crack here most likely will cause either an immediate or latent leaker. Can domes are formed by cutting circles of metal out of the plate and forming these discs on what is called a "hat press". This machine produces an intermediate end profile which is similar to the shape of a monk's hat with a wide brim, hence the name. The machine, or slide press, is operated at about 300 units per minute. The "hats" are fed into either a five or seven slide sequential press, operating at about 125 pieces per minute, where reforming dies produce what is essentially the final shape, including the one-inch (25.4 mm) hole surrounded by the curl or bead. Finally, a curling wheel, with a groove on the outside and a correspond- -1.221 ±.010 1334.001 Enlarged View of "Snaplock 006±. 002 Figure 6. Cross-Section of "Snap-Lock" 202-Dome Top Courtesy of the Continental Can Company, Inc. Figure 7. Cross-Section of "Snap-Lock" 211-Dome Top Courtesy of the Continental Can Company, Inc. ing groove on an outer segment, provides the rim or curl geometry, consisting of a peripheral channel around the end which is filled with a double seam compound, such as Continental Can Co.'s No. 318, made by the Dewey & Almy Division of W.R. Grace & Co. This compound, when cured, provides the seal between the end and body sections of the double seam when fabricated into the final can. The ' 'flat'' section just outward from the can curl is a weakening factor in dome design from an axial load standpoint. Yet it is needed to provide a surface to support the one-inch (25.4 mm) overcap or a double shell overcap. During warehouse storage of completed aerosol products, without a flat area for the overcap to rest upon, fatigue factors affecting the plastic might cause the cap to spread and then split, perhaps allowing actuation of the valve. Can companies design their domes and select their plate specifications in order to provide sufficient axial strengths to withstand virtually all warehouse storage conditions. Many design features are built into can domes in the interest of strength and aesthetics. One canmaker will not permit domes to elongate more than 0.025" (640 /on) at 140°F (60 °C) product pressures that may occur during hot-tanking; even then a 50% return is required of the design when the dispenser is cooled down to 70 °F (21 °C). The curl portion is available in either open or closed profiles, and some canmakers have more or less
The Technology of Metal Aerosol Containers 57 OPEN CURL CLOSED CURL CLOSED BEAD BARKLEY BEAD Figure 8. Various Can Bead Profiles Figure 9. Configuration of Open and Closed Can Curls standardized on a modified profile that reportedly contains the advantages of both extremes. Where Under- the-Cap (U-t-C) gassing is employed, open curl and modified open curl configurations provide clearance for liquid propellent, trapped within the curl, to escape instantly. In the case of tightly closed curls the liquid propellent sometimes took many minutes to seep away, causing these cans to resemble crimp leakers in the hot- tank. They were called "phantom leakers". Three representative can curls are shown in Figure 8. The modified open curl (not shown) is roughly halfway between the open and closed curl designs. The Barclay curl is a change in configuration initiated about 1975 by Continental Can Co. on their 202-diameter cans and subsequently extended to the other sizes. It has a straighter inside profile than standard curls, offering a better angle to crimp the valve against, thus giving a better, more positive crimp. Like every other curl it can be distorted greatly by marginal crimping. In fact, after crimping there is only about a 1 % chance of telling whether the bead was a Barkley type or one of the others. The use of open curl designs seems to be decreasing, since the other types provide a stronger design and are less apt to roll up more tightly under heavy crimping pressures, especially those exerted by the U-t-C gasser. Severely distorted can curls often lead to either immediate or latent (after several weeks or months) leakage problems. Curl designs as a parameter of crimp integrity are discussed more fully in the chapter on Crimping. In some cases it is desirable to determine the base weight of plate used for an aerosol can. This is especially important if the strength is questioned, either as the result of hot-tank eversions or ruptures, or because of a consumer liability action. The body base weight can be determined by flattening out this section and determining the thickness with a conical anvil micrometer. Weighing is also accurate; it is done by taking the exact weight of a3" x 3 "(76.2 x 76.2 mm) sheet. For 100# plate the theoretical weight would be 0.0287 lb. (13.01 g). In the case of end sections, the micrometer readings will be slightly lower than those of the original plate, due to the drawing action, especially on the dome. Domes can best be checked by weight, against standards of known base weight and equivalent profile. In the case of Continental Can Co. regular can bottoms the 118# 123 # and 128# base weights averaged 14.74, 15.36 and 15.97 g, resp. in a test involving 96 cans. Despite this apparent accuracy, end section weights from one or even a small group of cans may not be sufficient to tell with certainty what the original base Table X Dome Labeling Recommendations For Three-Piece Aerosol Containers* Can Diameter Type Size Statement 202 11 point SHAKE WELL BEFORE USING (Red** and black type) 207.5 14 point SHAKE WELL BEFORE USING (Red** and black type) 211 14 point SHAKE WELL BEFORE USING (Red** and black type) 211 14 point SHAKE WELL - KEEP REFRIGERATED (Red** and black type) 211 14 point SHAKE WELL - POINT ARROW AT DOT (Red** and black type) 300 14 point SHAKE WELL BEFORE USING (Red** and black type) *Developed by the Aerosol Committee, Can Manufacturers Instiute, 1625 Massachusetts Avenue, N.W., Washington, D.C. 20036, •Pantone Matching Number — PMS 179C.
o o n ■o c CO X "o CO o < H jo 1 Area (Vhere Used A. & Europ< A. & Europ< A. & Europ< U.S.A. Surope** U.S.A. Surope** cfl cfl cfl w j CO 3 S-s .2 S.S a ill ™ U Q g-o "s IS .8 ill 00 10 *-H(0©CMCMr~r~CMCMCM(0(OCMCM©~*r~r~r~~Hr~© cm r- r^ cm cm i-~ co © cm in n n ^ in to CMO>l-~CM00CMr^-HCM enoooiooiNCN'^io COI-~*CMCMI-~OCMCMI-~©(OCMCMCM (O -* rvaio^NioiooiOinNCftONO a> 00 t-~a>-Hina>©©oocMCM(OcocMCMoqcM'*'*'*^>oocM ^inr^n + iotdtDNNi^co'cftoicjid^r^cjpieoio CM ■* CO l-~ -* a> *-* co r~ cm co_ CM r-. CO CO 1 *h en n in id a> ■* — 1-^ CO CM io*NOtoM5i*"[onaiMiftai CM CO CO (O I— < ft, g.< < g. 3 3 _• „• 3 V V V V ix< •< ex <x< < ex a 0..00..00 »-i C/3 C/3 l-< l-iC/3C/3 l-< l-< 1) 1) 1) 1) 1) o, o, o, o, o, o o o o p t-l t-l t-l t-l & 3 3 3 3 3 W W W W W << e" Europ Europi §•08 08 s. Euro << s. U.S. U.S. Euro §• §• u 3 . 3 2 08 ai 08 ai W <j D <j D £>£>£> cfl cfl (X &,<! < < <X< (X OO * • * O ' O u t-. C/3 (/J (/J u C/3 »-■ 3 3 * 3 • 3 cfl a G C -0 C mm CMCMCMCMCMCMCMCMCMCMCMCMCMCMCMCMCMCMCM ^^ mmmmmmmmmmmmmmmmmmm ©© ©©©©©©©©©©©©©©©©©©© c c c c c r~ r~ r~ r-- r~ m m m m m © © © © © ©©©©©©©©© ©©©©©©©©© a -a mmmmmmmmmmmmmm© (0(0(0(0(0(0(0(0(0(0(0(0(0(0© ©©©©©©©©©©©©©©© ©m©©©mm©©©mm©©©©mmm©m© ■*r^^H©'*'^r^cTi-^-^CM'*r^r^ai©cncn(oai©m ©mm©© r^ en © cm m cm co ■* m (o ©©in©©©m©© noioiftONN+in eoen'*'*mmmm(o mmm©©m©©©m©m©©© r~a>©r~CM(0(0©mmcMa>©r^© coco-*-*ininin(0(0(or~r~coco© in © o> 00 13 0 C -0 C o> © ma>—<cmcm(0-ho>—<mi-~©ma> N"^ONCCOD0500^WeOeO**(0(ONCftOlO xxxxxxxxxxxxxxxxxxxxxx c c a a a r^ © ■* r~ r~ *-* ^ (o © m -h -h -h CM CM x x x x x r~ r~ r~ r~ r~ m m m m m CM«(O©O(O©00CM M + + (OM»5>5in xxxxxxxxx ©©©©©©©©© (0(0(0(0(0(0(0(0(0 a -a cococMCMi-~-H-H-Hincoinoo©(0© HrHN^ifti^NcooiCft^cn^ioo «„«««««„««CMCMCMCMcO xxxxxxxxxxxxxxx mmmmmmmmmmmmmmm (0(0(0(0(0(0(0(0(0(0(0(0(0(0(0 x x (O (O m ■n a in a a -a m co -* a> -H -H © co ■* m xxx CO CO CO ©co-*r~'*cMin(Ococo(00>'*inco©oo*-H'* 0«-H©-H©©©-H©©©«©©©©-H© CMCMCMcoco-*'*'*'*inininin(0(or~r~r^co xxxxxxxxxxxxxxxxxxx CMCMCMCMCMCMCMCMCMCMCMCMCMCMI^CMCMCMCM ©©©©©©©©©©©©©©CO©©©© CMCMCMCMCMCMCMCMCMCMCMCMCMCMCOCMCMCMCM a m 409 X 205 "3 508 X 205 a m 607 X 205 a m 802 X 205 1020 ni X 205 m coo>CMin*-*incoeoeo -H©«©©©©-H O ■*mm(or^r^r^r^cri xxxxxxxxx mmmmmmmmm r-' r-^ r-^ r*.' r^ r*.* r-^ r-^ r-^ a "^ "^ ~° eo ■* i^dno+NMwrHBiffltosiO" 0-H-H-«©-H-H©-H-H©©©©-H ***ift(O(O(OMsr^0DCJiCJi«^ xxxxxxxxxxxxxxx CMCMCMCMCMCMCMCMCMCMCMCMCMCMCM © © © © o © CO CO
The Technology of Metal Aerosol Containers 59 NOMINAL DIA- METER OF CAN DIMENSIONS SHOWN IN DRAWING BCD 45 52 57 65 Common Tolerance (mm) 43.6 (1.717") 50.7 (1.996") 55.5 (2.185") 63.2 (2.488") ±0.3 5.6 (0.220") 8.0 (0.315") 9.5 (0.374") 13.5 (0.531") ±0.6 2.9 (0.114") 3.2 (0.126") 3.3 (0.130") 3.3 (0.130") ±0.15 5.3 (0.209") 5.6 (0.220") 6.0 (0.236") 6.3 (0.248") +0.5 -0.0 45.2 (1.780") 52.7 (2.075") 57.8 (2.268") 65.9 (2.596") ±0.3 Figure 10. Proposal for Top End Dimensions for Necked- In Tin-Plate Aerosol Cans *For cans with a common test pressure of 12 bars (174 psi-g. or 120 MPa). For higher pressure cans (15.18 bars) plate thickness will increase and the dimensions will change accordingly. weight had been. This is because of the considerable variations of weight and thickness within each base weight, leading to overlap areas with adjacent standard base weights. Because of this, can companies have asked that the weights of can sections not be used in incoming inspection routines. In a similar vein, the original temper cannot be determined by the examination of can bases that have everted, since the original value would have been increased by the metal-working process of inverting. For domes, the temper can be read, but only by taking measurements on the breast area, where no profile changes would have taken place during eversion. There have been numerous attempts to standardize the dimensions of aerosol cans, even internationally. In the case of dome sections, during 1981 SEFEL made a proposal to the Federation of European Aerosol Associations (FEA) that certain dimensions for the popular necked-in tops be made standard, to harmonize with previous standards for the regular domes. Their recommendations are shown in Figure 10. Can bottoms are made from 100 to 135# plate, with tempers in the TU to T5 range. As a rule they are about one base weight lighter than domes, and about two temper levels higher since they are worked to a lesser degree in forming. Bottoms are rather simple to make, requiring only one forming operation, and more types of steel can be used than is the case for domes. One can- maker has already started to use double reduced tin- plate for bottoms, although rim cracking remains a potential problem. As mentioned earlier, the American Can Company, Continental Can Company and Heekin Can Division have developed and partially adopted the so-called dual-radius profile, as depicted in Figure 11. BREAK-POINT •LARGER CHUCK,WALL RADIUS Figure 11. The Dual-Radius Can Bottom Profile Data for Table XI on page 58: •Dimensions suggested by the Metric Working Group of the Can Maker's Institute, based on I.S.O. (International Organization for Standardization) diameters to the nearest whole mm, and can heights over the double seams (CSMA Dimension D) converted to the nearest whole **IGA (West Germany) and COLIPA. (Comite de Liason des Syndicats Europeens de lTndustrie de la Perfumerie et des Cosmetiques) ni = necked in (at the top only) and dni = double necked in (at both double seam areas). The current protocol for dimensions has been used in columns one and two, although this is being modernized in both Europe (I.S.O.) and the U.S.A. (C.M.I, and A.C.M.I.). Figure 12. Dual and Single Radius Can Bottoms The Continental Can Company dual-radius concave can base, shown at left, compared with a single radius can bottom. Several firms offer the dual-radius type, which is a stronger design.
60 The Aerosol Handbook Figure 13. Various Necked-ln Varieties of U.S.A. Cans The center can is a 211/300 x 709 by the Southern Can Company, necked-in at the top double seam area only. The other units are made by the Continental Can Company and are necked-in at both top and bottom. The can at the left is a 200-201/202 x 514 size Conoweld type. The others are 207.5/211 x 612 Conoweld units. During the forming of can bottoms the temper of the metal increases as the result of work hardening, but much less than for domes. For this reason higher temper plate can be used. In the U.S.A., by industry convention, can sizes are given as the diameter across the double seam times the can height (the base to the top of the top double seam, thus excluding the dome, such as 211 x 713). The first digit in each number is the number of inches and the last two are the number of sixteenth inches in addition. For example, a211 x713can has a maximum diameter of 2 11/16" (68.26 mm) and a total wall height (CSMA Dimension D) of 7 13/16" (198.44 mm). Figure 14. Three-Piece Tinplate Welded Side Seam Cans The 202 x 509 can at the left shows the modern necked-in feature at top and bottom. It may be compared with the regular 202 x 509 can at the right. The center unit is a 211 x 604 size, showing the Soudronic "Wima-weld" line of the side seam. Strictly speaking, this convention of "Sales Code Diameter" and "Sales Code Height" applies only to three-piece cans made in the U.S.A. It has been extended informally to two-piece "Spra-tainers" made by Crown Cork & Seal Co. and in the past to the now- obsolete "Pressure Master" and "Apache" cans. In the case of aluminum cans, only those made by American Can Company are identified by the supplier, using this system. For these two piece cans, since there is only one double seam, the "Sales Code Height" is taken as the total vertical wall height. All other suppliers of aluminum cans identify their containers by means of diameter times the overall height, measured in inches and using either a fractional or decimal system. The Canadian system of aerosol can nomenclature is identical to that used in the U.S.A., while Mexico follows the European metric system. In England, the U.S.A. Sales Code system was abandoned about 1975 in favor of a Commercial Description combining the nominal brimful capacity (a volume measurement to the nearest 5 ml over 100 ml) widi the overseam can diameter. Thus, a 211 x 702 can becomes a 600.065 container. This system is becoming a European standard, for both tinplate and aluminum containers. Table XI provides nomenclature and availability data for three-piece aerosol cans in both die U.S.A. and Europe. With the advent of the Soudronic welding process in 1966, it became possible to neck in the can body to allow the application of smaller diameter end units. Each individual necking in operation acts to reduce the body diameter by about 1/16" (1.6 mm) for die smaller cans or up to 1/8" (3.2 mm) for the larger ones. Thus a 202-diameter can could be reduced to a 201-diameter, a 211 to a 209 and a 300 to 214. In practice, this single reduction was not favored, especially for top ends designed to be fitted with a full-diameter plastic cap or spraydome. For one thing, a series of new diameter domes and overcaps would have to be prepared and inventoried; for another, applied overcaps would exceed the body wall diameter of the can, and tiiis would detract from the aesthetic appeal of die perfect cylindrical profile of finished units. Because of this, the upper area of die top single necked in bodies was reworked and necked in further, giving the larger diameter cans a "double waterfall" contour. The 202-diameter can is thus reduced to a 200-diameter, the 211 to a 207.5, and the 300 to a 211. The last two reduced diameters fit standard can domes.
The Technology of Metal Aerosol Containers 61 Starting about 1976, when necking-in seemed about to assume importance in both the U.S.A. and Europe, various aerosol standards groups wrestled with the development of a suitable system of nomenclature. Until 1979, the European (informal) convention was to identify these cans in accordance with the following two examples: a. Single necked in can: Top/Body/Bottom x Nominal Height; e.g. 52/57/57 x 207 b. Double necked in can: Top/Body/Botton x Nominal Height; e.g. 52/57/54 x 207. This plan was rejected by the F.E. A. Tinplate Standardization Subcommittee in 1979, in favor of a plan exemplarized as: a. Single necked in can: Body/Bottom/Top x Nominal Height; e.g. 57/57/52 x 207 b. Double necked in can: Body/Bottom/Top x Nominal Height; E.g. 57/54/52 x 207, which was in harmony with I.S.O./SEFEL (International Standards Organization/Society for European Container Standards). Later in 1979 all this information was reviewed by the CSMA Aerosol Division Commercial Standards Committee (Sub-group D), after which still another system was recommended: a. Single necked in can: Top/Bottom/Body x Nominal Height; e.g. 52/57/57 x 207 b. Double necked in can: Top/Bottom/Body x Nominal Height; e.g. 52/54/57 x 207. This proposal was submitted to the Can Maker's Institute (CMI), which they then shared with the American Can Manufactures Institute (ACMI). In mid-1979 both these organizations had indicated a preference for listing the body as the last of the diameter notations, and the proposal was in accord with that presentment. Those working in the area of converting U.S.A. and Canadian Sales Code Diameters and Sales Code Heights to their metric equivalents under the voluntary metric standards programs now in effect should note carefully that the Sales Code Diameter dimension is established as being 0.010" (254 fim) greater than the actual diameter across the double seams. Thus, a 202 diameter can has a maximum diameter of typically 2.115" (53.72 mm). In contrast, the European convention is to use the ideal design inside can body plug diameter rounded to the nearest whole millimeter. The 202 diameter can thus converts to one with a nominal metric diameter of 52 mm. In calculating nominal heights in the metric system, the starting point is CSMA Dimension D (CSMA Aerosol Guide). For every aerosol can this dimension is 0.020" (508 fim) less than the Sales Code Height distance. Thus for a 202 x 700 can, the Sales Code would indicate a nominal height of 7.000" (17.78 mm), whereas CSMA Dimension D gives the height as 6.980 ± 0.032"(177.3 ± 0.79 mm). The nominal metric can height is taken over the top and bottom double seams, the same as CSMA Dimension D, but with the result rounded off to the nearest whole millimeter. In the example, the nominal metric height would be 177 mm. Can capacity measurements can also pose problems, because there are at least three methods in use. The brimful capacity, as used in England and increasingly in Europe, involves filling the can right to the top with water and whisking any convexity away with a straight edge. By using water at 39°F (4°C) the density becomes unitary, and the can volume in ml will be the same as the weight difference between the empty and filled can in g, less any experimental errors, such as air bubbles in the chimes. The second measurement is that of net capacity: the internal volume of the can with the valve in place. This is again determined by filling the can with water, then pressing the valve in place to squeeze out any excess, and wiping carefully the dome dry before reweighing. A built in slight error of about 0.5 ml involves the draw-up factor, where the floor of the valve cup is slightly raised during crimping. Also, valves tend to have different cup and diptube displacements. This is probably the most realistic can capacity determination in relation to overfill considerations. The final method is now being studied by the CMI, and simply involves filling aerosol cans to the base of the curl with water at 68°F (20°C). It is an extension of studies begun on metric size F-style cans during 1979. The determination of can volume is important so that one can be assured of not adding an excessively large fill of product to an aerosol dispenser, thereby
62 The Aerosol Handbook HI '■■•K.I '«Si<T fEROSECT •i- . •*—•„'' Figure 15. Aerosol Cans of "Flit" and "Aerosect" A Continental Can Company "double concave" aerosol can of FLIT Insect Spray (EssoOil Company, now Exxon) made in 1951 and still functional in 1981. Also illustrated is an AEROSECT "bomb", an insecticide filled for Pennsylvania Engineering Company in 1946. inviting end bulging and possible rupture if the unit is heated. The DOT regulations merely state that the can shall not become liquid filled when the contents are heated to 130°F (54.5°C). In a more sophisticated document, the CSMA Aerosol Guide recommends filling to a volume of not greater than 95.5% of can capacity, measured at 130°F (54.5°C), provided that either the dome or bottom end can evert at significantly below burst pressures. Otherwise, fills of no more than 92.5% of can capacity at 130°F (54.5°C) are recommended. In Europe the maximum volume fill is described as 95% at 122°F (50°C). Japanese regulations are now being revised, so no figures can be given. In the U.S.A. there are no regulations governing minimum volume fills for aerosls. Although the National Bureau of Standards (NBS) brought up this issue under the heading of "non-functional slack fill" about 1968, nothing was ever done. In Europe the concept has been taken much more seriously by the EEC and led, in 1979, to an F.E.A. proposal for ten preferred can capacities and minimum volume fills, as shown in Table XII. Table XII Preferred Can Sizes and Volume Fills in Europe Federation of European Aerosol Associations; 1979 Minimum Fill Volume (20°C) Minimum Can Capacity (ml) Minimum Percentage Fill European I.S.O. Can Dimensions 100 ml 125 ml 150 ml 200 ml 250 ml 300 ml 400 ml 500 ml 600 ml 750 ml 140 175 210 270 335 405 520 650 800 1000 71.4 71.4 71.4 74.1 74.6 74.1 76.9 76.9 75.0 75.0 52x72 52x88 52 x 105 and 52 x 109 ni. 52 x 132, 52 x 136 ni and 57xll7ni. 52 xl61, 52 xl65 ni and 57 x 140 ni. 52 x 195, 52 x 199 ni, 57 x 164 ni, 60 x 146 and 65x122. 57 x207 ni, 60 x 186 and 65x157. 57 x 257 ni, 60 x 232 and 65 x 195. 65 x 240. 65x300. Notes: a. Only tinplate cans are considered in this tabulation, ni = necked in. b. The 52 x 72 and 52 x 88 cans are recommended by IGA (West Germany) and Coilpa c. All necked in cans except 57 x207 are recommended by CFA (France). d. For U.S.A. Nominal Dimension equivalents, see Table XII. e. Additional cans were considered earlier and may be brought up again as this work progresses. They include the 45 x96, 45 x 118 and 45 x 140 units, where the equivalent in the U.S.A. would be the non-existant 113-diameter. One proposal would restrict preferred can sizes to those made in at least three countries and in at least a volume of 5 million units per year. f. The volume per cent minimum fills are given for aerosols using liquified gases. For CO2 and N2O products the minimums are relaxed to about 55 v.% because of operational problems that might otherwise occur.
The Technology of Metal Aerosol Containers 63 Body Fabrication Techniques Can body plate is received as coiled or sheeted stock by the can manufacturer. For various diameter cans it is ordered about as shown in Table XIII, each can maker having certain preferences. The body plate, in typically 34" x 34 "(964 x 864 mm) squares, is subjected to some or all of the following manufacturing steps: a. First coating of liner enamel applied and baked on. Optional b. Second coating of liner enamel applied and baked on. Optional c. Base coat for lithography system applied and baked on. Optional d. Lithographed design applied and baked on. Optional e. Varnish top coat for lithography system applied and baked. Optional f. Sheets passed through slitter to produce body blanks. g. Blanks passed through body-maker side seaming. i. Soldered side seam, or ii. Soudronic welded side seam a) Regular weld, or b. Wima weld, or c. Super-Wima weld, or Conoweld I electroforged side seam, or Conoweld II wireweld side seam. Can cylinders passed through side seam striper. i. Internal liquid or powder sintered stripe, and/or Optional ii. External powder sintered stripe. Optional in. IV. i. Cylinders passed through flanger. j. Finished bodies passed through double seamer. i. Bottoms are seamed on. ii. Then tops are seamed on. k. Finished cans are tested in a drum pressure tester for leaks.* 1. Cans are arranged in palletized loads for shipping. *A low pressure device capable of detecting only gross leakers. Can Linings The vast number of formulations marketed successfully in steel and tinplated aerosol cans attests to the versatility of this packaging system. A truly anhydrous product, one with less than about 80 ppm of water present, has never been found to cause corrosion problems with these cans. But, where water is present, the possibility of interactions between dispenser and formulation must be evaluated carefully. In many instances, it is desirable to apply phenolic, epoxy or vinyl coatings to the inner surface of the container, including the valve cup, in order to minimize the effect of such incompata- bilities. The use of some corrosion inhibitors such as sodium nitrate, and sodium benzoate, also ammonium m-nitrobenzoate, morpholine, 2-methyl butynol, Expoxol 9-5 and sodium n-lauroylsarcosinate has also been found to be beneficial. Conversely, there are substances that function as corrosion promoters and they should be avoided. Examples are copper ion, chloride ion (also bromide and iodide), thiocyanate ion, sodium lauryl sulfate and carbonic acid. Rust, which is a form of hydrous iron (III) oxide, is a promoter, which explains why many corrosion reactions that form this Table XIII Body Plate Preferences For Various Can Diameters Sales Code Diameter 202 207.5 211 300 Non- Specification 65#DR8 to 75#T3 75#T3 or TU to 80#TU or T4 70#DR8 to 85#T4 85#TU to 90#TU Body Base Weights DOT Spec. 2P 70#DR8 to 80#T3 70#DR8 to 80# TU or T4 70#DR8 to 80#DR8 or 85#TU or T4 90#TU to 95#TU of ETP and CCO Plate DOT Spec. 2Q 80#DR8 to 80#T3 80#DR8 to 85#TU or T4 80#DR8 to 90#TU orT4 (Not made.) The 70# plate for DOT Spec. 2P and 80# plate for DOT Spec. 2Q. is selected from coils where over 99.7% of the area (three sigma) measures over 0.0070 " (178 itm) and 0.0080" (203 fan), respectively.
64 The Aerosol Handbook substance are self-accelerating. One of the reasons for using de-ionized water in many formulations is to prevent or control corrosion rates to acceptable levels. There are numerous aerosol products on the market which use de-ionized water and which would perforate the can rather quickly if ordinary hard water were to have been used erroneously in their formulation. In general, softened water, with its relatively high chloride ion content, is quite hard on aerosol cans. The simplest can lining is the epoxy-phenolic single coating, cured onto the tinplate or C/CO plate by baking, prior to fabricating the body. A further refinement is the application of an enamel stripe over the exposed side seam area. Different stripe compositions are used for pre-solder, post-solder and post-welding applications. Pre-welded stripes are impossible because of the very high temperatures involved. The golden epoxy- phenolic post-weld stripes are the most popular. They are applied as a liquid and cured in place by either electrical induction heating or flame heating the can body. Chemical resistance is very good, but there is often some shattering or flaking at the ends, when the metal is bent in the flanter and then hooked in the double seamer. This is due to the brittleness imparted by the phenolic component. To help resolve this problem American Can Company and others have developed urea-formaldehyde/epoxies. While they do not have the resistance of the phenolic hybrids, they give much improved protection at the ends of the welded seam. They are normally colorless when baked on, and the can companies are now in the process of adding colorants so that incoming component inspectors at filling plants will not think the side seam stripe is absent, merely because it is almost invisible. In the case of soldered cans, side seam striping was not as important as in welded types. The heavy coating of tin or lead/tin gave both physical and electrochemical protection to the underlying steel. In disinfectant/deodorants and several other products, the anodic or sacrificial action of lead was very beneficial to product compatability. But between 1979 and 1982, at least in the U.S.A. and much of Europe and Japan, a massive conversion to welded aerosol cans has taken place. The solder-type body-maker machines have sometimes been shipped to less technologically advanced countries. By the end of 1982, most U.S.A. can makers will no longer offer soldered can options, and those that retain solder-type lines will still do the bulk of their business in welded units, using the solder-type equipment only for special products that are incompatible with welded side seam containers, since they apparently need the anodic protection of lead. Certain disinfectant/deodorants, window cleaners and rug shampoos are in this category. The change to welded cans has acted to make side seam striping an extremely common step in the body-making process. The welding process is fraught with a number of idiosyncrasies which make the seam more susceptible to corrosion processes. Without a side seam stripe the cut edge of the body plate will expose the steel directly to the formulation. Since the Soudronic welding process is still an atmospheric one, much of the surface will contain traces of FesCX, FeO, FesC (cementite), possibly ferrite and remnants of the original FeSn2 alloy. These structures act to darken and roughen the steel surface; they protect it from corrosion in some cases and hasten product attack in others. Organic coatings do not adhere as well on this oxide oriented surface as they do on tin- plate, or particularly C/CO plate, thus they are less effective as barriers. The copper (oval) wire electrode used in the wireweld process to scavenge particles of molten tin, may leave traces of copper behind as a bronze alloy, and this can function as a corrosion promoter in some systems. Finally, even with the newer versions of the Soudronic process, there are still vestiges of the sharp edges and unbonded wings of the steel body plate. Sharp surfaces are often catalytic and will promote certain types of corrosion. Crevices under the wings readily spawn corrosion, perhaps due to the potential between oxygen-rich and oxygen-poor cells, but more commonly because of build-ups in detrimental ion species or the localized depletion of the inhibitor. With all these potential problems, it is easy to see why nearly all welded cans are also side seam striped. Although it is important only from an aesthetic standpoint, many welded cans are externally side seam striped. This is especially critical with the Conoweld I can, which uses C/CO plate, since this plate is much less resistant to corrosion than ordinary plain tinplate. The Conoweld I can is always single coated externally as a minumum, plus being given a side seam stripe. The stripe is applied after a very brief cooling of the weld area, using either a liquid or powdered organic material. The residual heat dries the liquid partially and acts to sinter on the polypropylene or other type of powder coating, after which further heating promotes a smoother surface and chemical curing of the stripe pre- polymers. For the Conoweld I can, the presence of inside and outside coatings aids in the lubricity of the plate in can making equipment.
The Technology of Metal Aerosol Containers 65 To this point, only single coatings have been described. Certain cans are double coated and at least one is even triple coated: some "Spra-tainer" base sections. A second coat coating is applied to further reduce statistical levels of metal exposure to the product, either by covering scratches, eyeholes, bruises or voids, or by minimizing the possibility of penetration that would lead to underfilm corrosion. The top coat is almost always composed of a different polymer mix than the initial coating. This means that in order to get through both coatings, the product must be able to affect adversely polymers with significantly different solubility parameters and other properties. Perhaps the ultimate in protection is a double-coated can plus stripe, where the top coat is a spray applied special vinyl or "Organosol" material. The usual double coat systems are flat applied to both body and end sections. The sprayed coatings are put on after the can segments have been formed completely, except for assembly. The cylindrical bodies are placed in a rotary holder within a special, Teflon-lined drum, then sprayed from a spray head moving lengthwise through them as they are spun about. The finished bodies are then baked at about 400 °F. These spray-clad coatings are about three times as heavy as ordinary vinyl topcoats. This is about as much as can be achieved reasonably without draping and other problems. They are only offered by some companies and sometimes only in specific sizes, or specific parts, such as end units only. Since the reduction of metal exposure to certain minimums is the major object of double coat can linings, the can companies use various pieces of electrical equipment to determine coating efficacy. The thickness of the coating can be measured in various areas by means of portable gauges, such as models F102 and F1002 (for steel substrates) and N52 (for stainless steel and aluminum cans), made by Surfatest, Inc., 5700 Thurston Avenue, No. 224, Virginia Beach, VA 23455. The overall imperviousness of the coating system is measured with portage gauges, such as the Model No. 10780 or 10781 Waco Enamel Rater and similar devices. In a typical test, the finished aerosol can is filled essentially to the brim with a sodium chloride (conductive) solution in water. An electrode is inserted in the brine and another is clipped onto an area of the can that has been scraped previously down to the bare metal. Conductivity is read by connecting these leads to the machine. If the conductivity is above a certain low level the coating system is considered defective. There is a body of opinion that coatings can literally be "too good". It is thought that they may expose an exceedingly tiny area of the can to the product, either initially or latently, so that the whole corrosive force of the composition gets concentrated into this minute locale, causing some severe effects, such as perforation. This may be true in a few instances, but is thought to be exceptional at best. Can linings are applied to tinplate, passivated (oxide- film) tinplate, C/CO plate, aluminum, naked steel and various solder compositions, during the manufacture of aerosol cans. They are usually baked on at up to 480°F (250 °C), either by the use of heated air, or better by induction heating. Induction curing works from the inside, causing thermosetting and solvent evaporation before gas entrapment can occur. It is very fast and provides a much improved junction between the coating and the underlying metal. Enamel lining specifications are determined best through a general consideration of the product, followed by test packing. For example, American Can Company's E-5 single coat epoxy is a highly successful lining, but it contains a colorant that is not certified for use with foods under the Code of Federal Regulations (21 CFR 175.300). For whipped creams, water-based frypan lubricant sprays and other food aerosols, their colorless E-9 version of E-5 can be used, but E-39 is preferred. It is essentially identical to E-5 but has a food-grade colorant. For double coat protection American Can Company may suggest their K-5 system, consisting of an E-5 or E-39 base coat plus a vinyl top coat. If the product contains a vinyl top coat solvent, such as methylene chloride, then either X-28 (E-5 or E-39 plus a phenolic top coat) or X-55 (a double coat of E-5 or E-39) may be used. Still further protection is afforded to end sections through the use of X-42, which is a system comprising either E-5 or E-39 as the base coat plus a gray' 'Organosol" top coat. This is not used generally on bodies. American Can Company offers several stripes. Their S-19 is an air-dried type, relatively low in resistance to ethanol and certain other solvents, still used on soldered cans but no longer specified on Soudronic types, where it has been replaced by another food approved stripe: S-41, whch is an epon-phenolic. Although the S-41 provides extraordinary protection so long as it is intact, it is relatively brittle due to the phenolic content, and this has caused loss of adhesion near the ends, when the body plate is bent to form the double seam hook. A newer stripe, S-79, consisting of a urea-formaldehyde-
66 The Aerosol Handbook epoxy hybrid, gives slightly less protection compared to intact S-41, but is more ductile and will not flake or crack near the seam ends during seaming. S-41 and S-79 are heat cured and gold in color. Continental Can Co. has a similar selection of linings. Their 83-GLD is used most commonly for single linings, usually in combination with a 392-GLD side seam stripe. Double coated systems commonly use 86-GLD/99-CLS, phenolic modified epoxy under vinyl, for the body (always with a stripe) and either 155-GLD/142-CLS or 155-GLD/159-GRY for the end sections. 155-GLD is the same as 83-GLD, but without the anti-eyeing additive, 142-CLS is a modified vinyl and 159-GRY is a grey-colored "Organosol" that can be applied flat and is not harmed significantly during the end-forming operations. In the case of Crown Cork & Seal Co. cans the terminology of Style 62, 64 and 65 is used to describe plain, single epon lined and double epon/vinyl lined three-piece cans, resp. For their "Spra-tainer" line, Style 7.3.2 signifies a single-coat epon-sprayed body and Style 7.4.4 designates the corresponding single- coat epon roller-coated bottom. Further descriptions of available can linings could be provided for all the can companies. For any product development program, it is best to consult directly with the can company technical service representative to get their up-to-date appraisal of what can lining systems should be specifically studied. They will then supply samples and possibly participate in the testing program. With the difficult economic picture that has characterized 1982 certain can companies have seriously considered assessing a charge for "casual" can samples. To illustrate the parlance of the can companies in describing finished aerosol units we can give the following example: CCC211 x 604 Conoweld I Top: 128# - #25 ETP-83GLD i/s-white o/s-318 compound Body: 70# - TFS 83GLD i/s-white o/s Bottom: 128#- #25 ETP-83GLD i/s-87CLS o/s-318 compound I/S stripe: 392GLD O/S stripe: 398GLD This can has a complete single epoxy enamel lining. The 318 compound refers to the flowed-in sealant used to make the double seams pressure tight. The entire outside surface is also coated; clear-colorless on the bottom and white otherwise. The body is suitable for either silk-screening (rare) or paper labeling. Linings can add as much as about 10% to the net cost of the aerosol can, so they should be used only when needed. The U.S.A. industry has a reputation for over-specifying; for using can linings where they are not really necessary. In many instances new products are the worst offenders, with can linings and other attributes over-specified to compensate for test pack limitations; and as an insurance policy for the risk of capital in a new introduction. They often fall back to more reasonable specifications as production line test packs mature, field experience is evaluated and more favorable can warranty positions are established with the can suppliers. Several can companies have elaborate electrochemical set-ups with which to evaluate container/product compatability, thus enabling them to give short term predictions on long term effects. In one technique, the "Driven Can Test" is used to accelerate strongly possible corrosion reactions. It is normally a 24 to 72 hour test, where a potential of about 1.5 V is applied. The can is then cut open and examined. In another, the galvanic current is determined as an indication of the intensity of the corrosion potential. The electrode potentials across various can metals are also determined to see what materials will be anodic; E.g. tend to corrode or dissolve. In a typical example, an experimental rug shampoo (pH = 8.62) was tested in a double lined and striped 2/98 soldered can, giving three results: Galvanic current: 1.64 jta/cm2 Electrode potentials; open circuit values: Coupled: 571 /tV Steel: 377 /tV Heavy oxide, crevice corrosion. Tin: 640 /tV 2/98 Solder: 672 /tV Slight corrosion. Driven test; 1.5 V for 24 hours: Shallow pit at bottom crossover of body and end in pressure ridge under silicate film (from product). The galvanic current showed that both low-tin solder and tin are anodic to steel with solder the most active anode. The overall opinion was that the product might cause an occasional perforation, but should have a reasonable shelf life in the test can variable. The accuracy of the preliminary electrochemical evaluation varies with the time under test and with the type container, but runs approximately as shown in Table XIV.
The Technology of Metal Aerosol Containers 67 -?Qf s-S**TTy xofAS. ■j-/*rry X0 / AS- J>XowcT /7 #Alf yf*4o* SS £*£*#. Vary SllgKc siiehc Moderate Farforation Thin Film Siiehc Buildup M»daraca Buildup Savara Buildup Dollar fi la EjWffiii... _2S£ s*»rry Mo f A-Jt. swryl DECREE t ' Slight Q Hod«rac. COWPITIOH 1 Plnbliaearlng 2 BiiaCating 1 Blush 4 OlccoLoratloa 5 Softening • Lifting Product is moderately darker Yellow in color in comparison to that stored at 70° F Figure 16. Worksheet Recording Can Evaluation DATA Product: Hydroalcoholic, phenolic-type disinfectant/deodorant spray. Propellent: Hydrocarbon Test Pack: #79-C 369 Container: 202 x 509, #25, single epon lines, with epon-phenolic side seam stripe and Soudronic welded body. Miscellaneous: Vacuum crimp of 17" Hg° (42kPa-absolute) The greatest problem involves intermediate or long term reversal of polarity, and this is important especially in welded cans for such products as window cleaners, water-base hair sprays and disinfectant/deodorant sprays. Incompatible products which become compatible also show slow changes in electrode potentials. For instance, either most or all water-based lecithin-type frypan lubricating sprays rise in pH value from typically 4.0 to 5.5 during storage as the lecithin Table XIV Accuracy of Electrochemical Prediction of Test Pack Results Incompatible Compatible Where Where Actually Actually Container Accurate Compatible Compatible Tinplate or CCO plate with soldered side seam 85% 10% 5% Tinplate or CCO plate with Soudronic or Conoweld side seam, resp. 85% 8% 7% Aluminum 82% 10% 8% macromolecules take up hydrogen ion via various mechanisms. This causes a stabilization of the container/product system. These considerations point to the absolute need for test packs. Working with the can companies, and perhaps on the basis of electrochemical prognostications, two or three dispenser variables are selected for study. A minimum of 36 cans of each product or valve variable is prepared, with 24 often going to the can maker and the rest being retained by the marketer or contract filler. One can maker stores a few cans at 130°F (54.5°C) for a month, before cutting and evaluating them, but the majority store half the cans at 70°F (21.1 °C) and the rest at either 98 °F (36.7 °C) or 100°F (37.8°C). They are generally stored upright, since this position is by far the most common for field storage. In the past examinations were normally made at 1, 3, 6 and 12 month anniversaries, with reports issued to the marketer or filler. But by 1982 major cutbacks in Customer Services or Technical Service departments have caused a marked attrition of these free services from the can companies. Sometimes only one or two cuttings will now be made on a given test pack. It is uncommon for 70 °F (21.1 °C) cans to be cut for the one month evaluation. Figure 16 shows a typical worksheet for a disinfectant/deodorant at six months. This particular formulation is one which shows an apparent increase in corrosive intensity with time, perhaps as a result of the increased breaching of the lining and the catalytic effect of rust. Despite the finding of scattered very light to moderate pitting in the 98°F (36.7°C) variable at six months, the formula has now been shown to perforate plain #25 ETP cans in five months, single lined and s.s.s. cans at ten months and double-lined s.s.s. containers after twelve months at this temperature. The perforations always occured at the body wall next to the bottom double seam. "Organosol' ' variables were not tested, but would probably last at least fifteen months at 98°F (36.7°C). This is still too short a period for commercial acceptability. Test pack results are always reported on the basis of the worst can seen per variable, and shelf lives are estimated in the same fashion. Thus, an aerosol that has a shelf life estimation of ten months in the field would have had at least one can perforate in about eleven months at 98°F (36.7°C) out of the twelve cans tested at that temperature. The rest of the cans might reasonably be expected to perforate during the next six months or so, but this time frame is very uncertain. There are many test pack and field examples where one
68 The Aerosol Handbook or more cans perforate and the others never do. In the case of starch products, most commercial formulations are beset with a very occasional field perforator, yet 99.9 + % of the cans are essentially perfect in internal appearance after a year or two. Test packs are often used as a means of securing a special container warranty by the can supplier. By means of this legal document the canmaker agrees formally to extend his customary good workmanship and materials warranty to include: a. That the can has the proper specifications to fit the intended purpose. b. That the containers will provide a one year service life (normally) after filling, for the stipulated formulation, provided: i. The marketer complies with all government rules and regulations ii. No changes are made in formula, filling technique, or vacuum level. c. The marketer provides some stipulated number (24 to 48) of cans to the canmaker from the first production run. Special container warranties are almost always provided for a twelve month term. In one rare case a few two-year warranties were reluctantly given by two can companies to a large insecticide marketer. In some cases, six and nine month warranties have been offered; especially where the storage time for test packs has been limited to a few months and the results looked promising. The can makers have different philosophies with respect to warranties. One has made the informal statement that the document is protection only against container perforation. Such other aspects as double seam failure (rare), weight loss, internal corrosion or detin- ning, organoleptic effects, as changes in product color, odor or enzymic activity, secondary damages due to shelf leakage, and so forth are all outside the purview of coverage. Another can maker has limited the tenure of their warranties to the year of issue, leaving it up to the marketer to press for timely re-issuance for each following year. One purchasing practice, that has has an extremely negative effect upon warranty programs, has been to show the warranty of one can maker to another, so that the second firm can offer a "sales-initiated warranty" of duplicate coverage, thereby qualifying for some or all of the available business without having invested in the sizable storage and testing program that led to the initial warranty. This has led one or more can makers to strongly deemphasize their interest in warranty development and maintenance. The advent of the welded side seam can has brought further problems into the troubled area of product warranties. The welded can is more capricious than soldered tinplate variables, although less so than aluminum. The anodic protective influence of tin and lead is missing. The weld area has an extraordinarily complex chemistry, containing various oxides, carbides, carbon, perhaps copper and tin, and sometimes other trace heavy metals. The physical surface properties are likewise very complicated, involving an intricate panoply of crystal layers, micro-pinnacles (usually cata- lytically active toward corrosion reactions) and labyrinthine crevices. The pandurate non-metallic scales have low enamel adhesion, posing an additional problem. It has been estimated that up to 5% of the products that have been successfully packaged in soldered cans cannot be commercially packaged in the welded types. Faced with electrochemical assessments that are less reliable than before, and with test packs that may not agree with commercial production results in terms of corrosion development, the can companies are naturally more reluctant to offer warranties for welded can variables. There are, of course, exceptions, where welded cans are preferred for certain products — aside from their economic advantages. One strange but interesting circumstance involves oven cleaners and all-purpose cleaners, sometimes called "double seam detinning seepers". These high-pH products apparently have the ability to slowly perforate through the bottom double seam and build up tiny deposits against the outer body wall. In relatively low humidity weather the alkali content gradually turns to carbonate/bicarbonate, but at higher humidities the deposit becomes semi-liquified and absorbs oxygen. It then exerts a strong corrosive effect upon the can, sometimes leading to perforations from the outside in. At higher temperature storage, the can base is forced downward from the increased pressure of the contents, thus tightening the double seal and reducing percolation. As a consequence the problem is greater at lower temperatures of storage. Similarly, at the junction of soldered side seam and the bottom double seam there is a "fat spot", seven tinplate layers thick. This area literally invites percolation, whereas the equivalent area of a welded can (with the equivalent of only about 5.4 layers) does not. Welded cans are the preferred variable for these products.
The Technology of Metal Aerosol Containers 69 In some cases the electrochemical differences between soldered and welded cans can be accommodated by a change in corrosion inhibitors in the product. For example, a de-icer formula, containing methanol, ethylene glycol, water and carbon dioxide slowly attacked both plain and lined soldered cans until 0.15% morpholine was added as an inhibitor. But when the formula was tested with welding cans, corrosion again became a problem. The morpholine (in the form of morpholinium bicarbonate in the solution) was ineffective. Other inhibitors were then tested, and it was found that either ammonia or ammonium carbonate gave good results. Hair sprays have shown interesting experimental results. Essentially anhydrous formulas containing the Resyn type film formers (typically, a methylvinyl- ether/maleic anhydride copolymer) could not be packed in cans soldered with "2/98" or other lead-containing alloys, because lead was anodic and gradually went into sodium solution up to levels recorded at 520 ppm. and perhaps higher. Pure tin solders were satisfactory, but such cans were more expensive. Now, in the welded cans, Resyn formulas are stable even without the usual side seam striping, whereas the BASF, Gantrez and other tackifiers are almost always packaged with striped cans due to their higher pitting potentials and selective attack of grain boundaries. Side Seam Constructions The concept of using solders to bond metal surfaces is undoubtedly thousands of years old. It first was applied to tinplated cans about 1740 in England, and to aerosol cans by 1946. By 1966 the first welded side seam cans were made in Belgium, using the process developed by Soudronic, S.A. in Switzerland, and by the end of the 1960's both Soudronic S.A. and Conoweld cans were being made in the U.S.A. As welding techniques gradually improved, it became obvious that they had many economic and design advantages over the soldered varieties. Some are listed as: a. Reduced container weight. b. Elimination of the economic burden of using lead and/or tin metals. Tin was priced at over $8.00/lb. ($17.60/kg) in 1981. c. Reduction of unsightly side seam surface from % " to 7/s" (19-22 mm) down to about 7/s2" (5.5 mm); e.g. a reduction of about 73%. d. An expansion of the area available for lithographic decoration. e. Adaptability to necking-in operations. i. Production of stronger, lighter containers. ii. Use of straight cylinder designs, with full- diameter caps. iii. Reduction of maximum can diameter, with reduction of up to 8 v.% in case sizes. f. Utilization of more reliable RVR, PRM and other dome designs for the safe and automatic discharge of overpressurized cans. g. Ability to shape or contour the body wall for design individuality. h. Elimination of the "solder creep'' problem, where the side seam slowly spread apart under higher pressure stress, ultimately causing leakage. i. Elimination of tinplate, as an available option, in favor of C/CO plate. A number of solder constructions and compositions have been used in the U.S.A. as shown in Table XV. By mid-1982 the transition from soldered to welded cans was over 97% completed. A total of 110 welded lines were available to produce welded aerosol cans, food cans and other types. The obsolete solder-type bodymakers are being shipped abroad as they are replaced with weld-type machines. By the end of 1982 American Can Company, Continental Can Co. and Crown Cork & Seal Co. may have eliminated their solder-type facilities altogether, and the industry will depend upon lines maintained by National Can Co. and Heekin Can Co. for soldered side seam constructions. Many of the cans run on these lines will be for products still incompatible with welded can variables, often despite extensive research on inhibited formulas and related approaches. Because of the unrushing obsolescence of soldered cans for most products, the technology of these side seams is not further discussed. Instead, the reader is referred to an extensive treatment in the first edition of The Aerosol Handbook, or to other trade books and journals. As is often the case with change, the main force behind the move to welded side seam cans is economics. The various canmaker's solders, normally about 98% lead, came under heavy pressure from the FDA, the CPSC and other agencies dedicated to reducing the amount of lead pick-up in consumer products, most notably foods, hair sprays and paint sprays. Except for paints, where lead can originate as an impurity in the Next Page
The Technology of Metal Aerosol Containers Previous Page In some cases the electrochemical differences between soldered and welded cans can be accommodated by a change in corrosion inhibitors in the product. For example, a de-icer formula, containing methanol, ethylene glycol, water and carbon dioxide slowly attacked both plain and lined soldered cans until 0.15% morpholine was added as an inhibitor. But when the formula was tested with welding cans, corrosion again became a problem. The morpholine (in the form of morpholinium bicarbonate in the solution) was ineffective. Other inhibitors were then tested, and it was found that either ammonia or ammonium carbonate gave good results. Hair sprays have shown interesting experimental results. Essentially anhydrous formulas containing the Resyn type film formers (typically, a methylvinyl- ether/maleic anhydride copolymer) could not be packed in cans soldered with "2/98" or other lead-containing alloys, because lead was anodic and gradually went into sodium solution up to levels recorded at 520 ppm. and perhaps higher. Pure tin solders were satisfactory, but such cans were more expensive. Now, in the welded cans, Resyn formulas are stable even without the usual side seam striping, whereas the BASF, Gantrez and other tackifiers are almost always packaged with striped cans due to their higher pitting potentials and selective attack of grain boundaries. Side Seam Constructions The concept of using solders to bond metal surfaces is undoubtedly thousands of years old. It first was applied to tinplated cans about 1740 in England, and to aerosol cans by 1946. By 1966 the first welded side seam cans were made in Belgium, using the process developed by Soudronic, S.A. in Switzerland, and by the end of the 1960's both Soudronic S.A. and Conoweld cans were being made in the U.S.A. As welding techniques gradually improved, it became obvious that they had many economic and design advantages over the soldered varieties. Some are listed as: a. Reduced container weight. b. Elimination of the economic burden of using lead and/or tin metals. Tin was priced at over $8.00/lb. ($17.60/kg) in 1981. c. Reduction of unsightly side seam surface from % " to 7/8" (19-22 mm) down to about 7/s2" (5.5 mm); e.g. a reduction of about 73%. d. An expansion of the area available for 69 lithographic decoration. e. Adaptability to necking-in operations. i. Production of stronger, lighter containers. ii. Use of straight cylinder designs, with full- diameter caps. iii. Reduction of maximum can diameter, with reduction of up to 8 v.% in case sizes. f. Utilization of more reliable RVR, PRM and other dome designs for the safe and automatic discharge of overpressurized cans. g. Ability to shape or contour the body wall for design individuality. h. Elimination of the "solder creep'' problem, where the side seam slowly spread apart under higher pressure stress, ultimately causing leakage. i. Elimination of tinplate, as an available option, in favor of C/CO plate. A number of solder constructions and compositions have been used in the U.S.A. as shown in Table XV. By mid-1982 the transition from soldered to welded cans was over 97% completed. A total of 110 welded lines were available to produce welded aerosol cans, food cans and other types. The obsolete solder-type bodymakers are being shipped abroad as they are replaced with weld-type machines. By the end of 1982 American Can Company, Continental Can Co. and Crown Cork & Seal Co. may have eliminated their solder-type facilities altogether, and the industry will depend upon lines maintained by National Can Co. and Heekin Can Co. for soldered side seam constructions. Many of the cans run on these lines will be for products still incompatible with welded can variables, often despite extensive research on inhibited formulas and related approaches. Because of the unrushing obsolescence of soldered cans for most products, the technology of these side seams is not further discussed. Instead, the reader is referred to an extensive treatment in the first edition of The Aerosol Handbook, or to other trade books and journals. As is often the case with change, the main force behind the move to welded side seam cans is economics. The various canmaker's solders, normally about 98% lead, came under heavy pressure from the FDA, the CPSC and other agencies dedicated to reducing the amount of lead pick-up in consumer products, most notably foods, hair sprays and paint sprays. Except for paints, where lead can originate as an impurity in the
70 The Aerosol Handbook formula, the government would like to see lead levels at about 0.2 ppm or less. In the U.S.A. there has been a reduction from an average of .32 ppm in 1974 to 0.22 ppm in 1980 and this trend is continuing, especially in the food and pharmaceutical area. The need for lead- free can constructions left the industry with three options: tin solder, welded side seams or seamless cans. If one considers a tin soldered can carrying 4.54 g (0.01 lb.) of tin in the side seam, at the 1981 price of tin, an imported, cartel-controlled material, the cost of solder becomes about $0.08/can. No matter how this burden is distributed it is an almost unbearable add-on to the cost of making large aerosol cans. Turning now to the seamless can, such as the Crown Cork & Seal "Spra- tainer", the obsolete American Can Company "Pressure-master" and the obsolete National Can Co. "Apachecan", the deep-draw or drawn-and-ironed methods used to make these units are not competitive with those used for three-piece containers. Depending upon can size and other factors, at least 12% had to be added, above the three-piece prices, in order to make these containers profitably. As a result, only the "Spra- tainer" survives, and even here the manufacturer has informally suggested that marketers should give preference to three-piece cans (and not use the "Spra- tainers") whenever practical. This leaves only the welded container as the ultimate choice for tinplate or C/CO aerosol cans. (See Figure 17). In the Soudronic welding process, sometimes called "The Wireweld Process", a continuous band of tinplate from 6.7 " (170 mm) to 9.2 " (234 mm) wide is shived into a long cylinder with the edges overlapped by about 0.100" (2.5 mm). Welding is performed on the lapped area, using twin electrodes of eliptical cross- section tinplated copper wire. The heavy tin coating of the electrode wire is used up during the process, and this has led to the term "Lost Wire Process" for this operation. On a typical 80# MRTU plate under 90 pounds (41 kg) of welding pressure, a 10 ampere, 60 cycle sine-wave current will produce a welded joint of Table XV Solder Codes for Aerosol Containers Company Continental Can American Can Crown Can Div. Heekin Can Div. National Can Southern Can Co. Solder Code 2/98 Tricom Pure Tin Duocom Q,-ll (inside tabs) 0,-12 (inside tabs) 0,-13 (inside tabs) 0,-14 (inside tabs) Q.-18 (inside tabs)' Q.-21 (outside tabs) Q.-22 (outside tabs) Q.-23 (outside tabs) 0,-24 (outside tabs) 1.1 Lead 1.2 Hr-str. Lead 7.1 Pure Tin 7.2 Hi-Str. Tin 7.3 Tin P.C. 5 High Tin High strength lead High strength tin (Only welded) Tin 2 1.4 100 98 2 100 2 99.85 95 2 100 2 99.85 2 1.5 100 95 99.5 1.5 95 1.5 95 — Chemical Lead 98 98.1 0 0 98 0 97.5 0 0 98 0 97.5 0 98 98 0 0 0 98 0 98 0 — Composition (%) Antimony 0 0 0 2 0 0 0 0 5 0 0 0 0 0 0 0 5 0 0 5 0 5 — Silver 0 0.5 0 0 0 0 0.5 0.15 0 0 0 0.5 0.15 0 0.5 0 0 0.5 0.5 0 0.5 0 — 'Obsolete. Available only temporarily on special large orders. Note; It is estimated that virtually all soldered cans will be obsolete in the U.S.A. after 1982.
The Technology of Metal Aerosol Containers 71 IMN •i ' 1' '_ i *T*Ne we Figure 17. Examples of Seamless Can Bodies The can at left is a 12-oz. Crown Cork & Seal Company "Spra-tainer" in DOT Specification 2Q construction. The other two are excellent but now obsolete cans made by the Apache Division of National Can Corporation in 211- and 202-diameters. some 2.62 times the original plate thickness. Part of this thickness is due to the non-parallel juxtaposition of the plate in the lapped area. The initial Soudronic machines operated at about 25 feet (7.5 m) per minute, but in 1971 larger machines were introduced that could handle speeds of about 100 feet (30 m) per minute. Two weld points are obtained for each electrical cycle; thus 7,200 weld modules per minute at 60 cycles per second (60 Hz). At a plate travel of 30 feet (9.1 m) per minute, this means that a weld would be produced every 0.050 " (1.27 mm) of plate length. It is necessary to use tinplate and a tin coated electrode for the process, so that the tin can be melted and drawn into the micro- structure or interstice between plate layers, thus filling up all the tiny crevices that would otherwise exist. The higher speed model has a more complex welding system, but the number of weld points per inch remains about the same. A typical Model HSP machine, operating at 109 feet (33 m) per minute, will produce can bodies of the 211 x 604 size at the rate of 206 units per minute. This weld was technically acceptable, but the large "step'' at the cut edge was aesthetically offensive. Some people even cut their fingers slighdy on the sharp edge. This ultimately led to the Soudronic "Wima-weld" process (after WIre-MAsh, indicating the procedure) in which me basic technoloy remained the same, but the overlap area was reduced to about 0.026 " to 0.30 " (665 /im to 760/im) and the thickness at the plate lapover area reduced to about 1.37 times the original single plate thickness by mechanical compression of the hot metal. As before, tin was used to fill in the micro- crevices, although there was still not enough to cover die cut steel edge. Tests have shown that even 0.05# ETP (at 0.000002 " or 56 nm on each side) has sufficient tin for crevice filling. Except for the 114-diameter (45 mm) cans, which run rather slowly, the welding process runs at linear speeds of about 220 to 230 feet (67 to 70 m) per minute, which equates, for example, to a production rate of about 425 211 x 604 cans per minute. In 1981 about 70% of all U.S.A. three-piece aerosol cans were made by this process. The latest development in Soudronic welding came with the advent of the "Super Wima- Weld" process. In this case the lap width has been reduced at least another 0.008 " (203 /im) to about 0.016 " (405 /im) making the weld almost a butt-weld in design. Thickness at the overlap has been reduced still further, to about 1.2 times that of the original plate. This feature is thought to enable Super Wima-Weld cans to function acceptably as piston cans. While this modification has been used by at least one U.S.A. aerosol canmaker, it shortly was discontinued, since even a slightly out of register condition may lead Table XVI Modifications of the Process For Welding Cans Tradename Developer Plate Used Status Soudronic (Original) Soudronic Wima-weld Soudronic Super Wima-weld Conoweld I (C/CO) Conoweld I (ETP) Conoweld II (C/CO) Conoweld II (ETP) Soudronic Corp. Soudronic Corp. Soudronic Corp. Continental Can Co. Continental Can Co. Continental Can Co. Continental Can Co. Tinplate Obsolete (1968 - 1977) in U.S.A. Tinplate 1973 to present. Most popular. Tinplate 1975 to present. Unpopular in 1981 in U.S.A. Very popular in Europe, due to technology and controls on process. C/CO Plate 1971 to present. 202 & 211 cans only. Tinplate Introduced 1980 for 211. (202 in 1982). C/CO Plate Under development in 1981. Tinplate Introduced 1980 for 207.5 cans but to be extended to all diameters by 1983.
72 The Aerosol Handbook —O Seam Uotw Surface Lowe' Surtac* Romng Electrode W»tdM SoMSwm Ro«>ng Electrode Ftxce Figure 18. Soudronic Wireweld Manufacturing Process Figure 19. The Continental 'Conoweld T Process to loss of overlap or even an open crack. There is less metal to generate heat as the electric current goes through. In some cases tin fills in where the steel does not quite come together, and this may lead to numbers of cans ' 'unzipping'' or opening up during hot tanking, or even gassing, as the tin fractures. In England, faced with the same problems, the Metal Box Ltd. people developed an engineering control system that "reads" the quality of each weld as it is made, with a feedback feature to guide the operation toward making optimum side seams. Virtually all the Metal Box three-piece cans are made in this fashion and they have made their technology available to other companies interested in saving a bit of metal and getting a cleaner, highly reliable weld. The Super Wima Weld is now used in the U.S.A. for baby food cans and other items as well. Further improvements in the Soudronic process will probably relate to shielded welding, as an improvement over the atmospheric welding now performed. The technology is in place, but the added cost is an economic problem. By eliminating the air, production of surface oxides will cease, although some carboniferous alloys will still be present on the weld surface. Other current efforts are directed at designing bead structures to achieve optimum strength, especially when using lightweight base weight stocks, such as 65# DR8 plate. The can companies are still expanding their Soudronic welding capabDities. For example, American Can Company installed a 300 x 709 Soudronic line at their Regency, NJ plant in late 1981 and another in their Englewood, IL facility in early 1982. This gave them fifteen can sizes. Metal Box Ltd. in England also has fifteen can sizes. Crown Cork & Seal Co. is perhaps unique in having 202 x 200 and 202x214 cans available with welded side seam constructions. The Conoweld system was introduced by Continental Can Co. about 1971, and with it the first use of C/CO tin-free, double reduced steel plate. Despite very early statements to the contrary, the original Conoweld process (now called "Conoweld I") cannot be used for tinplate, although it does have potential for use with nickel plated steels and other types. It is a rolling electrode system, especially designed for production of an electro-forged side seam at high production speeds. In the welding procedure, body blanks of C/CO DR8 steel are edge-cleaned and then passed into a special Conowelding bodymaker. Here the blanks are rolled into cylinders, flexed to minimize panelling, and then lapped slightly so that the edges can be tacked together accurately by spot welding to fix the exact can diameter. About four tacks are used ona211 x413 can and six on a 211 x604 size. The cylinders are then passed through the seam electro weld station, where the continuous weld is produced. A special 500 cycle per second (500 Hz) square wave current provides a nearly continuous heating effect. The welded section is about 0.040" (1.0 mm) wide and about 83% as thick as the original double thickness of the overlapped sheets. The Conoweld I process is used to produce cans of all diameters, from 202 to 300, but it is somewhat oriented toward high volume productions in the major standard sizes. For those customers wishing to have tinplate variables, and perhaps shorter runs of less common size cans, Continental Can Co. developed the Conoweld II process, which is essentially a Soudronic type lap and wireweld method. The company installed such lines in their plants in the early 1980s. Welded side seams vary greatly in quality. There are excessively hot welds, "cold" welds, welds with blowholes, interplate crevices, rust occlusions, even welds with gaps so large that the can contents can escape within a second or two after gassing. The more bizarre types can sometimes be detected during incom-
The Technology of Metal Aerosol Containers 73 ing inspection by the filler, but most are encountered during hot tanking. In some productions, over 98% of all hot tank rejects have been weld leakers. They sometimes come in surges, where one operator can scarcely remove bubbling cans from the tank quickly enough to keep up. It is at hectic times like these that relatively slow weld leakers can pass through undetected. For these cans, if the leak is located below the liquid level in the can, it may stain the final shipping case and be detected a few days later, particularly if the case is located on the outside layer of the pallet, or if it is handled individually in a drop-shipping operation. Whenever an unusually high incidence of welded side seam leakers is encountered during hot tanking, the operator should be on the lookout for cans that leak only at the rate of one gas bubble every ten or twenty feet. These are the insidious "hypoleakers". They are very hard to detect, but are still sufficient to ruin a can within a month or two. In some cases they may mysteriously stop leaking, only to start up again after a few months. If hypoleakers are seen, another person or two should be stationed at the hot tank, and any can showing a gas bubble clinging to the cut edge of the welded seam should be scrutinized to see if it is slowly growing. In one instance a rug shampoo markerter experienced a rather steady complaint level of about 40 defective cans for every million sold. Of those that were returned, two out of three were found to be hypoleakers. The supplier evaluated the cans and admitted that the weld was imperfect in every instance where leakage was involved; no can corrosion was detected, as sometimes happens with this type product. Table XVII U.S.A. Tinplate and CCI-Steel Aerosol Can Sizes (Availability from various can makers) Can Size Can Capacity* * American Continental Crown C&S Heekin National Ring Sexton Sherwin- Williams Southern 200 202 202 202 202 202 202 202 202 202 207.5 207.5 207.5 207.5 207.5 211 211 211 211 211 211 211 211 211 211 x200 x214 x314 x406 x411** x412 x509 x700 x708 x808 x509 ix605 'X701 x708 ix713 x214 x315 x412*** x413 x503*** x604 x612 x713 x908 xl008 211/214x411** 300 x709 100 ml 144 ml 198 ml 223 ml 216 ml 240 ml 287 ml 364 ml 388 ml 436 ml 386 ml 446 ml 497 ml 521 ml 538 ml 238 ml 324 ml 396 ml 401 ml 433 ml 523 ml 564 ml 649 ml 792 ml 876 ml 370 ml 793 ml X X X X X X X X X X X* X X X* X X X X X X X X X X X X X* X* X X* X* X X X* X* X X* X X X* X* X* X* X* X X* X* X* X* X X X X X X X X X X X X X X X x' x' X X *These containers are also produced on the West Coast, for fillers in that area. "'Measured as minimum volume can, with valve crimped in place. ***Two-piece (seamless) tinplate containers.
74 The Aerosol Handbook '•ttW! NE* WWI SCtHTEO "WYSPflAT "EOOORAWT "ftukiiijj soda tf All/Of Figure 20. A Personal Product Line, Packaged in Three- Piece Tinplate Aerosol Cans The two-three piece tinplate cans illustrated are a 202 x 509 (with 8 Av. oz. fill) and 207.5 x 605 (with 12 Av. oz. fill). Both "Scented" and "Unscented" versions of the product are listed in both can sizes. The products are by Johnson & Johnson, Inc. Figure 21. Aerosol Products Are Packaged in Standard Cans Varying in Height and Diameter A size comparison of one of the shorter cans (202 x 214) with one of the taller varieties (211 X713) in common use. KZR, a product of Texize Chemical Co., is used to remove fabric stains by dry silica absorption. SHIMMER is an all-purpose institutional cleaner/polish marketed by Drackett Industrial Products Division in a can that makes use of the brilliant, clear-varnished tinplate surface to promote cleanliness and elegance. M R ( < DUST REMCfl *" out* "<tiii«k ''Hllli 'IFMfNT si in»\r ° >. Figure 22. Aerosol Can of DOT Specification 2Q A two-piece drawn tinplate 211 x 412 lithographed can used for an institutional DUST REMOVER product. The can is made by Sexton Can Company in a DOT Specification 2Q style, since the content is pure dichlorodif luoromethane (P-12) with 130°F(54.4CC) pressure of 181 psig (1,241 Pa). U.S.A. Two- and Three-piece Tinplate or Steel Cans It is important for research, purchasing and marketing people to know about can availability: what sizes are available, and from what suppliers and locations. Some cans are made by only one supplier. Using them will automatically invite such possible problems as unavailability during strikes, higher freight costs, monopolistic pricing policies and even the discontinuance of the line. Examples of such one-supplier cans include the soldered variables, which will probably be made only by the National Can Corp. after 1982, in four 202- and four 211-diameter sizes, and only with 95% tin/5% antimony high-strength solder. In addition, the Cono-weld and Sepro-cans are made only by the Continental Can Co., U.S.A., and the two-piece cans are now made only by Crown Cork & Seal Co.; e.g. their six and twelve ounce "Spra-tainers". The regular can sizes produced in the U.S.A. are shown in Table XVIII. Special cans are not shown. For instance, Continental Can Co. makes three tops for their 202-diameter cans: the regular top, the 200-diameter necked-in dome and the unique "Sepro"
The Technology of Metal Aerosol Containers 75 can top, which has a special curl dimension to accommodate the thickness of the plastic alloy bag. Variations in plate thickness have essentially no effect upon can capacity figures shown in the table. A 211-diameter regular strength American Can Company can has a capacity of less than one ml greater than their DOT Specification 2Q(RVR) can, with 135#top, 80#body and 128# bottom. The choice of valve cap will sometimes cause a change in dispenser capacity, up to about one ml. The conical cup displaces the least volume; the Precision Valve Corp. cups with nylon liner and other deep wall profile cups displace the greatest volume. Can linings do not measurably affect container capacity. Where the can contains an inner container, such as the "Sepro" can bag or the PressPack Corp. bag, now supplied by the Southern Can Co., the container capacity must relate to bag volume, not can volume. Aluminum Containers Aluminum cans are considered to comprise about 8.5% of the U.S.A. aerosol market, for a sales volume of about 184 million units in 1980. The percentage is only slightly higher in Mexico and the U.K. However, in Europe, overall, aluminum cans probably enjoy about 30% of the market. Despite their obvious aesthetic appeal, aluminum aerosols suffer from problems of higher cost, product compatibility limitations and (in the U.S.A. and Canada) a general lack of availability in sizes larger than about 13 fl. oz. (325 ml) overflow capacity. Production js also somewhat more fe '» il I Figure 23. One-piece Drawn Aluminum Aerosol Cans A variety of one-piece drawn aluminum aerosol cans made in the U.S.A. The cans are made by the Peerless Tube Company and are trade-named "Peerasols". Products are (left to right) COLIBRI Butane Fuel Refill (2.40 Av. oz.), POLO Antiperspirant (4.00 Av. oz.), MEDI-QUICK First Aid Spray (3.00 Av. oz.), SANTA CLARA Antiperspirant Spray (2.50 Av. oz.), ENZACTIN Athletes Foot Spray (3.00 Av. oz.) NORFORM Feminine Hygiene Spray (9/16 Av. oz.), BINACA Concentrated Golden Breath Spray (1/3 Av. oz.) and FRESH LIPS Moisturizing Spray (1/4 Av. oz.). difficult; aluminum containers must usually be inserted into pucks with steel incorporated into the bottom in some fashion, to enable fast handling on magnetic conveyor equipment. There are several aluminum aerosol can suppliers in the U.S.A., plus a number of others who serve the U.S.A. market, often maintaining domestic sales offices to improve their services. These firms are shown in Table XVIII. These suppliers make a very wide diversity of tubes and cans by the process of impact extrusion. Sizes from about V3 fl. oz. (10 ml) to 100 fl. oz. (2.96 liters) are available. A few cans in the smallest sizes are available Table XVIII Aluminum Aerosol Can Suppliers To The U.S.A. Corporate Name Advanced Extrusions, Ltd. Alusuisse of America, Inc. & Alusuisse Metals, Inc. Swiss Aluminum Ltd. American Can Company Cebal Division Pechiney Ugine Kuhlmann Devel. Inc. J.L. Clark Manufacturing Co. Cliff Impact Division Parker Hannifen Corp. Emson Research, Inc. Impact Container Corp. Metal Box Limited Peerless Tube Co. Victor Industries Corporation of California Virjune Manufacturing Co. White Metal Manufacturing Co. Division of Wheeling Stamping Co. Brandname — Boxal Mira-spra and Mira-flo Cebal Monobloc E-10-19 One-piece — Peerasol Victor — — Home Office Canada Switzerland U.S.A. France U.S.A. U.S.A. U.S.A. England U.S.A. U.S.A. U.S.A. U.S.A. U.S.A. Sales Office — Fairlawn, NJ Greenwich, CT New York, NY Eastlake, OH Bridgeport, CT Rochester, NY — Bloomfield, NJ Chico, CA Waterbury, CT Hawthorne, NJ
76 The Aerosol Handbook Figure 24. Monobloc Aluminum Container A large (2.88" x 11.0") container made by Cliff Impact Division of Parker Hannifin Corporation. This size is often used for dairy barn insecticides and other institutional products. Tare is 131 g and capacity is 1.060 kg. with a 13 mm beaded opening. Small, intermediate, and a few large sizes (to 11 fl. oz. or 322 ml) are made with a 20 mm curled opening. And lastly, the intermediate and larger containers are offered with the standard one-inch (25.4 mm) finish. A number of standard and custom can profiles are produced, as indicated in Table XIX. The shaped cans, made by Alusuisse Metals, Inc., are produced in twenty standard patterns plus various custom designs that are proprietary to specific Figure 25. Monobloc Shaped Aluminum Aerosol Cans Four examples of Alusuisse (Boxal Division) monobloc shaped aluminum aerosol cans now available from stock in Europe. See Figure 26 for other examples and design limitations. customers. The top 3.15" (80 mm), as measured downward from the base of the bead, is available for shaping. Three basic shapes are offered: faceted (ovals, lozenges and polygons), multi-rings (wide, narrow, "fir cone" and composite) and curved ("bullet", necked in, spindle and composite). The shaped containers are supplied in 35, 45, 50, 55, 59 and 66 mm diameters and in heights from 70 to 259 mm. Aluminum aerosol can suppliers vary considerably in the diversity of sizes offered; one firm makes only two standard sizes, whereas Boxal produces over 120 and Cliff Impact Div. is prepared to extrude 2.5", 3", 3.13", 4" and 4.5" diameter units into any desired height within the capacity range of 15 to 100 fl. oz. (444 to 2,960 ml). A substantial sampling of available can Table XIX Aluminum Aerosol Container Profiles - 1982 Canmakers Monobloc Monobloc Monobloc (With 1 " (25.4 mm) Finish) Two-Piece 13 mm Round 20 mm Round 2-Step Straight 1" Straight Shoulder Round Shoulder Shoulder Round Shoulder Shoulder Regular Regular Shaped Regular Shaped Regular Regular Shaped Regular Adv. Extrusions Boxal Division American Can Co. Cebal Division J.L. Clark Mfg. Co. Cliff Impact Emson Research Impact Container Metal Box Limited Peerless Tube Co. Victor Industries Virjune Mfg. Co. White Metal Mfg.
The Technology of Metal Aerosol Containers 77 sizes is given in Table XXI. For sizes other than these, the marketer should contact the various suppliers. For example, the unique Cebal 40 and 50 mm diameter cans (both 20 mm and one-inch beads) are not shown. There may also be discontinued sizes and new sizes. Most extruders can provide special container heights (and wall thicknesses), provided the customer pays the tooling charge, or if the proposed manufacturing order is large enough. There are literally hundreds of aluminum aerosol can sizes in Europe. In 1974 the EEC recognized the great proliferation of both tinplate and aluminum aerosol can sizes and began considering ways to limit the number as an aid to the customer. Starting with Article 8 (l)(c) of Council Directive 75/324 on May 20, 1975, the EEC began working in conjunction with aerosol industry associations to limit can sizes and make them relate to a set of specific, "neat", round number (of ml) minimum fill volumes, more readily identifiable by the consumer. In Sept-1979 the FEA, representing industry in Europe, was able to recommend a pattern of ten minimum fill volumes and ten Figure 27. Award Winning Aluminum Container Aluminum container by Alusuisse (Boxal) is sold only in Europe. VIVELLE Hair Spray is marketed by Cadonett. VheBe corresponding minimum can capacities for tinplate cans, (see Table XIII) and a similar set of sixteen minimum fill volumes and sixteen corresponding minimum can capacities for aluminum cans, see Table XXII. Figure 26. Shaped Aluminum Aerosol Cans < x o I c/> >- CD ° E /J=S I Faceted Multirings *-, P^N { \L=! Curved Drawings—Courtesy of Alusuisse Metals, Inc.
78 The Aerosol Handbook Table XX Aluminum Aerosol Cans Available in the U.S.A. Round-shouldered Monobloc Size Designations (Inches) (Sales code) (mm) Overflow Finish Capacity (mm) (ml) Peerless Emson Manufacturer or Distributor Victor Virjune Metal Box Cebal Alusuisse % x 215/16 5/a x 2'5/16 %x4 7/a x 2%2 % x Vk 7a x 3 15/16 x 2Va 15/i6 x 2% %x3 1 x 27/a 1 x 3'3/16 1V32X25/16 l'/32X3% l'/32X33/4 1'/32X4'/16 lVax2'/2 l'/ax35/8 l'Ax43A 1% X 2'/2 1% x 2%6 1% x 2% 1% x 3 1% x 37/16 1% x 3'3/16 I%x4% 1%x5'/2 1%X5'V.6 1'/2X43/16 l'/2X4"/16 1V2X5 IV2 x 55/16 l'/2x57/8 1V2X6V2 13Ax33A 1% x 4'/8 1%x4'/2 I%x49/16 1% x 4% 1% x 4% l3Ax4'5/16 1% x 5'/16 1% x 5% 13A x 5'A l3Ax55A6 l3Ax53/8 010x215 010x215 010 x 400 014x205 014x208 014 x 300 015 x 202 015x206 015 x300 100x214 100x313 101 x 205 101 x306 101 x312 101 x401 102 x 208 102 x310 106 x 208 106 x 209 106x212 106x300 106 x 307 106x313 106x412 106 x 508 106x511 108x311 108 x 403 108x411 108 x 500 108 x 505 108x514 108 x 608 112x312 112 x402 112 x408 112x409 112 x410 112 x412 112 x415 112 x501 112 x502 112x504 112 x505 112 x506 16x75 16x75 16 x 102 22 x58 22 x64 22 x76 24x55 24x60 24x76 25x74 25x97 26x59 26x85 26x95 26 x 103 29x64 29x79 104x412 32x121 35x63 35x66 25x70 35x76 35x88 35x97 35 x 120 35 x 140 35 x 145 38x94 38 x 106 38x119 38x127 38 x 135 38 x 149 38 x 165 45x95 45 x 105 45x114 45x115 45x117 45 x 120 45x125 45 xl28 45 x 130 45 x 133 45 x 135 45 x 136 13 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 25.4 25.4 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 10 10 14 21 23 27 21 23 30 35 46 29 42 47 51 38 55 88 57 54 59 68 75 86 105 125 130 96 111 127 133 142 156 172 130 145 162 163 166 171 177 181 184 188 191 192 *20 mm finish
K)|sJ|sJ|sJ|sJ|sJ|sJ|sJ|sJ|sJNJ|sJK3lsJK)|sJK) K3|sJ|sJ|sJNJ|sJ|sJ|sJ|sJ|sJ|sJ|sJK3lsJ|sJ K3ND|sJK3K)|sJ|sJK3lsJ|sJ|sJ|sJ|sJ oaoaoaoaoaoaoaoaoaoaoaoaoaoaoaoaoa oawwoawwwoaoawoaoaoaoaoaoaoa xxxxxxxxxxxxxxxxx xxxxxxx h-MMMMiriincococococosjciijioioi 00 *-J *^l *^l ^J *^l -J xxxxxxxx ooooooooooooo 00000000000000000000000000 to Co Co to Co Co Co Co Co Co Co *^o to xxxxxxxxxxxxx xxxxxxxxxx O^O^O^O^OiOiOiUiUiUi oooooooooooooooooooooooooooooooo oaoaoaoaoawoaoaoaoaoaoaoaoaoaoaoaoaoaoaoaoaoaoaoaoaoaoaoaoaoaoa xxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxx MMMMh-l£ll£lCOCOCOCOCOv)aia)CnOiaivJvIslv]s)sI(ji(jia)Oia)yiCnCn 4" **J Ol isj ** ooooooooooooo ^*-.*-.*-.*-.h-*-.*-.*-.. XXXXXXXXXXXXX XXXXXXXXXX O^-O^-^-OOOOO^-^-O k-OOO^-^-^-^-OO OiO«OiOiUiOiOiOiOiOiO«OiO«0«0«OiOiOiUiUiOiOiOiO«OiOiUiUiOiOiUiOi OiOiOiOiOiOiOiOiOiOiOiOiOiOiUiOiOiOiUiOiOiOiOiUiOiOiO«UiOiOiOiOi xxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxx ODOlOlU'OiOSWNDMh-OOCOviaiyi.f. ^Oi£>inCOODvisjaiCiCiCn^WW WOOi'-'^OtOOO^I'OOOiOiOiND CnCnyitnCnyitnyiyiv xxxxxxxxxxxxx xxxxxxxxxx yiOOuirouifON300ioco4» OiOiOOiOOOOiOaisJO OiOiUiOiOiOiO«OiOiOiOiOiO«OiOiUiUiOiUiOiUiOiUiOiOiOiOiOiOiOiOiUi 4"K3lsJ4>'4>'4>'4>'4>'4>'4>'4>'4>'4>'4>'4>'4>'4>' 4*4>'4>'4>'4>'4>'4>'4>'4>'4>'4>'4>'4>'4>'4>' 4*4»-4»-4»-4»-4»-4»-4»-4»-4»-4»-4»-4»- ^4»-4»-4»-4»-4»-4»-4»-4»-4»- OUi*-N)N)aivlwWKlOl£lW^OUiWCnls300l£lMvIUi^WW^O'Nl^ OiOUiWOJMOCOsIUilsDMK ^OONJi— i— "--OOOtO yi^^MCnyiOOUiNSMUiCO 004*CT>tOK>tOOiK>K-.00 XXX XX XXXXXXXXXX XXXXXXXXXXXXXXX XXXXXX X ^XXXXXXXXXXXXX
oooooooooooo oooooooooooooooooooooooo X X 00 00 xxxxxxxxx xxxxxxxxxxxxxxxxxxxxx i"-- ~~ flO"- i^ M"- 0^~ — ^ »~ ■*** -«W M-"1 —"~ —"~ »~~ -^V" ->^W i""" i""" m"- O* xxxxxxxxxxxxxxxxxxxx OOOOOOOOOOOO xxxxxxxxxxxx K-O^-i— ^-^-O^-OOh-O OCooi*"^^wyico^OOi OOOOOOOOOOOOOOOOOOOOO ooooooooooooooooooooo xxxxxxxxxxxxxxxxxxxxx OO^-^-OOOOO^-^-OOOO^-^-^-^-^-h- 4>-eo4>'ivoooo^eoisjoeneoooeneoisjeneoisjisJ4».eo xxxxxxxxxxxxxxxxxxxx o^o^o^enenenenenenen4»4»4»-4»-4»-4»-4»eoeoeo ooo^-^-^-oooo^-^-^-^-ooo^-^-^- XXXXXXXXXXXX fO NJ NJ NJ *-■ ** K> ^- O O ^1 ^1 o y n) o *-o enenenenenenenenenenenenenenenenenenenenen OOOOOOOOOOOOOOOOOOOOO xxxxxxxxxxxxxxxxxxxxx oaiyii-ooifcvjuiisDO^ooiMOuiwi-o enenenenenenmenenenenenenenenenenenenen xxxxxxxxxxxxxxxxxxxx o^wociui'CoiwoaiwOMwrooo 4>.4>.4>.4>.4>>-4>>-4>>-4>>-4>>-4>>-4>>-4>>- 4^4^4^4^4^4^4^4^4^4^4^4^4^4^4^4^4^4^4^4s.fcf*. 4^4^4^4^4^4^4^4^4^4^4^4^4^4^4^4^4^4^.hf*.hf». (O^-enOO^en^^ONJ^lO eoeoeoeoisJ|sJ|sJlvOlsJ|sJNDIsJ|sJ|sJ|sJ|sJ|sJ|sJ|sJ«-'«-' OCnOCOM^CO^O^^yDyiWOiCOOJO^OiOi WIsjMMMOO^^COvJslslOiOiOigi^WM MO)COOlOCOOWOOiy3tnOM<CCOIJiOJl<C
The Technology of Metal Aerosol Containers 81 Table XXI — (Continued) Alusuisse Straight-Shouldered Aluminum Cans (Made in Europe - readily imported) (Inches) 2.165 x5'5/16 2.165x7% 2.165 x8'/,6 2.165 x9% 2.323 x515/16 2.323x6% 2.323 x 713/,6 2.323x8 2.323x8% 2.323 x85/16 2.323x87/16 2.323 x93/16 2.323 x 10% 2.323 x 10% 2.323 x 10% 2.323x11% 2.598 x6"/,6 2.598x7% 2.598 x8V,6 2.598x8% 2.598x8% 2.598x8% 2.598 x813/16 2.598x9% 2.598 x 10% 2.598 x 103/,6 2.598x11% 2.598x12% Sales Code 203x515 203 x714 203 x 801 203 x 904 205 x515 205x610 205 x713 205 x 800 205 x 804 205 x 806 205 x 807 205 x 903 205 x1002 205 x1004 205 x1008 205 x 1102 209x611 209 x 708 209 x 801 209 x 802 209 x 804 209 x 808 209x813 209x912 209 x1002 209 x1003 209 x1004 209 x1206 (mm) 55 x 150 55 x 200 55 x 205 55 x 235 59 x 150 59 x 168 59 x 198 59 x 203 59 x 209 59x211 59x215 59 x 234 59 x 257 59 x 260 59 x 267 59 x 282 66 x 173 66 x 190 66 x 205 66 x 207 66x210 66x215 66 x 224 66 x 248 66 x 257 66 x 259 66 x 285 66x314 Finish (mm) 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 25.4 Overflow Capacity (ml) 315 430 443 510 364 405 486 499 514 520 534 582 643 650 655 708 520 586 607 613 623 639 668 745 800 805 888 993 Table XXII Total Height of Monobloc Aluminum Aerosol Cans (Round Shoulder) Capacity to Overflow (ml) 40 47 75 89 110 130 140 175 210 270 335 405 520 650 800 1000 35 51 59 88 102 125 146 156 38 77 90 110 128 138 40 83 100 118 125 156 45 81 94 102 125 150 191 50 106 125 155 190 226 53 114 142 172 205 Container Diameter 55 132 160 191 58 148 176 222 59 141 169 214 267 (mm) 60 140 167 209 64 185 230 65 146 183 224 66 143 178 218 263 74 210 258 77 169 202 246 80 228
82 The Aerosol Handbook The fill volumes were based on liquid fills to from about 71 to 77% of the can overflow capacity, in the case of products with liquified propellents, such as the hydrocarbons, chlorofluorocarbons and dimethylether. In the case of compressed gas aerosols, special fill volumes in the area of 55 % of the can volume were anticipated, due to the need for more headspace for these products. On Feb. 25, 1980 the EEC published their Annex III, listing standard can capacities and fill volumes, and stating that aerosol products complying with this Directive need not be marked with the nominal weight of their contents. This listing is shown in Table XXIII. The Directive also states that aerosol containers with the volumes as shown in Annex III cannot be refused in trade between EEC member countries. As of mid-1981 no tinplate or aluminum aerosol can made in the U.S.A. would fit the EEC Directive or have "neat" round number metric fill volumes. This could have serious consequences for marketers involved in long- term international trade activities, particularly trade with EEC countries. On June 9, 1980 the TC52 committee of ISO (International Standards Organization) met and decided to establish a new sub-committee: ISO TC52 SC3, to study the terminology and metrology of aerosol cans, giving special attention to nominal diameters and nominal fill volumes. This determination came as a direct result of the EEC Directive and Annex III. The hope to establish the type and direction of aerosol can standards by about May, 1982. Their conclusions will have global impact, and would thus have profound effects upon future tinplate and aluminum can sizes in the U.S.A. As one aspect, GATT (The 1979 General =S-J? Figure 28. Aluminum Tube Used For Foam Product VESPHENE FOAM, a cutaneous antiseptic based on an alcoholic solution of 2,4,4' trichloro-2'hydroxyphenol ether. Manufactured in France. Fine print on the container is smaller than 4-point type. Table XXIII EEC Directive (Annex III) Giving the Range of Volumes For Products Sold in Aerosol Form (Metal containers) Container Capacity (ml) Volume of Liquid Phase (ml) 25 50 75 100 125 150 200 250 300 400 500 600 750 Products Propelled by Liquefied Gas 40 75 110 140 175 210 270 335 405 520 650 800 1000 Products Propelled by Compressed Gas 47 89 140 175 210 270 335 405 520 650 800 1000 — Notes a. Compressed gas products must not also contain liquified gases and the Bunsen coefficient must be 1.2 or less. b. Products sold in glass or plastic aerosol containers are covered in a different category. The liquid phase must have a volume of 25, 50, 75, 100, 125 or 150 ml. c. Medicinals and certain other products are excluded. Agreement on Tariffs and Trade Section, entitled "Agreement on Technical Barriers to Trade") states that the regulatory bodies of signatory countries shall use relevant international standards when writing regulations to control import trade. As a result, these countries will not be able to ignore those standards that will eventually be developed by the ISO TC 52 SC3 group. There are many other commercial aspects surrounding aluminum aerosol cans. The 184 million \uru Figure 29. Ring "*• * at Can Shoulder lAl1 Hts Plastic Overcap p-wi.* A pair of 202-diameter (52 mm) aluminum aerosol cans produced in France, featuring a small indented ring at the shoulder to fit "sTiap- on" plastic full-diameter caps.
The Technology of Metal Aerosol Containers 83 *BE- ftSEHGt Figure 30. 1980 de Emballage Award for Brut 33 \ ra OXAL This 5.92 fl. oz. (175 ml) aluminum can was custom shaped by Alusuisse (Boxal) for Faberge's famous BRUT 33 cologne. In 1980 it was awarded the coveted French Oscar de Emballage award for excellent and innovative design. The straight tube of 11%6" (49.2 mm) diameter is extruded and trimmed to a height of 5%" (149 mm). After inside lining, oven curing and litho printing, the tube is necked in and reduced to the 20 mm opening during 24 progressive die stages. The excellent flexibility and adhesive properties of the can lining allow it to survive unharmed. aluminum aerosol cans produced in the U.S.A. during 1980 is a very tiny percentage of the aluminum container market as a whole, actually less than 0.1%. By comparison, the Alusuisse Castor II Process plant in Europe produces 300 million pounds of aluminum coiled strip per year, and the Pearl Container Co. plant in San Antonio, TX can make over 700 million beer cans per year using typical 48" (1.22 m) wide aluminum sheet. Those companies that provide aluminum aerosol cans are invariably in the business of making other items as well, such as tubes, bottles and structural forms. The Peerless Tube Co. provides the starting billets of aluminum to all the other aluminum aerosol canmakers in the U.S.A., except the American Can Company. Most aluminum aerosol cans are produced from 99.5% pure aluminum. Such alloys as 1170 and H19 have been used for high strength requirements in the larger size cans, but the more common approach is simply to increase wall thickness. For example, standard 1V2 " (38 mm) diameter cans with 0.012 to 0.014" (305 to 356 fim) walls will resist pressures of 600 psig (4.14 MPa), and increasing the thickness to 0.030" increases pressure resistance to well over 1000 psig (6.89 MPa). In practice, extra strength is needed only in extremely rare circumstances, such as in gaining UL (Underwriter's Laboratories) approval for certain Figure 31. European Designs for Aluminum Cans Typical cans are shown in this photo. The Boxal unit is decorated with a combination of metallic red and brilliant gold, to indicate the lithographic capabilities. products. The standard cans made or imported into the U.S.A. will all readily meet or (in most cases beat) the DOT Specification 2Q pressure requirements. Metal thickness increases as size increases. One major supplier, making can sizes from 60 to 1000 ml, suggests that his containers will withstand from 180 to 340 psig (1.24 to 2.34 MPa) in the standard thicknesses — the exact resistance depending upon size, contour and other factors. The geometry of the sealing area of aluminum containers is of utmost importance since it is most susceptible to seepage or leakage of the product. The containers with a 13 mm opening have various contours at die top, of which die one in Figure 32 is typical. I -15.2 ±0.2n 13.0* 0.2 n *©.5*0.2n mi » H > 1 1.5 mi t *A| (D t 2.0 mi T - 4.5 * 0.3 mm Figure 32. Typical Contour of a 13 mm Aluminum Tube A=Approximate point where the crimping indentation of ferrule and necked-in can wall is made. The top contour of the can then assumes the "S" contour. The tops of Virjune Manufacturing Co. cans and other 13 mm cans are bent inward to a lesser degree than the example shown here.
84 The Aerosol Handbook For the aluminum cans with a 20 mm opening, the "S" contour, inside bead and outside bead are all in current use. For instance, the "S" contour is preferred by the Virjune Manufacturing Co. While it is relatively simple to form this neck finish (the seal is made by forcing the cut edge about a third of the way through the ferrule sealing gasket), some laboratories have been unable to prevent excessive weight losses in the case of formulations containing strong solvents, such as Propellent 152a or methylene chloride. The Peerless Tube Co. uses the inside bead construction for their 20 mm finish cans, and, in fact, for their entire line of 21 standard size Peerasol containers, which include 13 mm and 1 " (25.4 mm) neck sizes, except the 2.089 " (53 mm) diameter cans. There are at least two general designs for 20 mm cans with outside bead construction: the "round bead" and ' 'rounded rectangular bead''. The first is typically used by such European firms as R. Lechner, S.A. (West Germany) and Tubettificio Ligure Sp.A. (Italy). The second is used by Cebal (France), Boxal (France) and others. Four 20 mm designs are sketched in Figure 33. 31.3 * 0.2 mm 31.3 * 0.2 mm ROUND BEAD FINISH - OUTSIDE TYPE 31.3 ±0.2 mm 22.2*0.2 20.0* 0.2 mm "S" CONTOUR TUBE FINISH 20.0* 0.2 mm, , ROUND BEAD FINISH - INSIDE TYPE 20.0*0.2 14.0* 0.2 mm mm I « © •¥ © ' ROUND BEAD FINISH - OUTSIDE TYPE ROUNDED RECTANGULAR BEAD FINISH Figure 33. Finish Designs for 20 mm Aluminum Tubes Figure 34. Finish Designs: 25.4 mm Tubes, Cans The standard 1" (25.4 mm) aluminum can is the most common type. It utilizes at least three basic designs of the round bead construction. The inside bead and outside bead are widely used, and then there are also some cans that are necked to form a solid bead. Most suppliers provide only the outside bead, such as Cebal and Boxal Sales Division — and the American Can Company which produces a somewhat modified form. The Peerasol cans generally use an inside bead. The three basic designs are depicted in Figure 34. Such factors as bead dimensions, bead strength, bead eccentricity and parallelism are very important to the quality of the clinched or crimped seal. In some cases there are legislative or regulatory restrictions. For instance, the Japanese Ministerial Ordinance No. 53 of MITI (Enforced Regulation for High Pressure Gas), Article 12 (d)(i & ii) limits the largest size diameter of aerosol cans to 3.15" (80 mm) and the thickness to a minimum of 0.0085" (0.215 mm). Considered worldwide, some aluminum cans are wider than this diameter limit, and nearly all tinplate cans are thinner than the thickness minimum. Some of the smaller aluminum tubes are also thinner, particularly in the bead area.
The Technology of Metal Aerosol Containers 85 31.3 ± 0.2 mm Machined area 31.1 * 0.2 mm 0.76 * 0.13 mm 0.25 ± 0.06 mm malnum 1100-F. * Illustrated as 27.2 mm in this example. Figure 35. Typical European 1" (25.4 mm) Bead for Aluminum Can Showing Machined Section The sketches in Figures 32, 33, and 34 do not include the machined area at the top of the bead which is standard for European cans, but which is rarely used in the U.S.A. The machining step is used to provide either a smooth, flat surface, a flat surface with very small circular grooves or (in the unique case of the Cliff Impact Division cans) a single, circular groove. As the aluminum can bead is formed through progressive die stages in the necking machine it may have small radial compression furrows that make it much more difficult for the cup gasket to effect a hermetic seal during crimping or clinching. Other factors such as non-planarity, eccentricities due to warp, spring-back and so forth may also be present and they also act to debilitate the gasket seal, so that latent leakers may eventually result. All these negative factors can be largely overcome by machining the top of the can bead. According to several canmakers, machining is especially important for beads of cans over 2.09 " (53 mm) since they are more subject to abnormalities. Where beads are not machined, the manufacturer normally takes very special pains to produce an extra high quality bead during necking. Figure 36. Typical Cliff Impact Division 1" (25.4 mm) Bead for Aluminum Can, Showing Groove* 'Aluminum containers with and without groove are available. The FEA specification for the minimum inside diameter of the machined area is 26.9 mm, but this is currently under review, with the possibility of enlarging it to 27.6 mm. Certain rather corrosive formulations, normally packed in double-lined aluminum cans, are said to be able to etch and pit the more accessible inner locus of the present 26.9 mm minimum diameter ring of bare metal. A typical 26.9 mm machined bead is shown in Figure 35. Another advantage of the machining step is that the tiny grooves (or single large one in the case of Cliff Impact Division) assist in holding the cut gasket in position and may provide a unifacial effective compression of the gasket that adds to the sealing effect of the flat compression factor. The "Cliff' grooved bead is shown in Figure 36. In order to make a good seal the gasket must be sufficiently compressed between valve and can, and minor (partly elastic) deformation of the hollow bead must also occur. The loading force applied by production crimpers on 1" (25.4 mm) beads is between about 285 Figure 37. Progressive Collapse of Aluminum 1" (25.4 mm) Bead as Pressure Load Increases 35° = Clinching forces influence the bead in a direction which is at an angle of about 35° to the vertical centerline of the bead He = Initial Contact height He'= Final Contact height CD = Curl Deformation (Vertical)
86 The Aerosol Handbook 1.1 ' 2 f 1 ° 9 a * w Q B ■ ■ — n _ n a n a n ■ _ ■ r ■ — s *~" s r B» r - S ~~ - s ~T" 1 1 !*iS I "I™ Z1 r sg ~' h— s\ J ~* — • *- _j r — —■ / / j- 1 "^l ,- ~ / / ' - s - *' ■~* ~~ / f — ' - n > ' "~ '' y -> r / 7* / - / / ~ _ _ ~ / / 7 -' — "~ -" 1 t / Hj - - — "~ »1 , / / ' •'i -s n ^. i. n n 0 50 100 ISO 200 250 300 COMPRESSIVE FORCE (Kg) Figure 38. Relationship of Curl Deformation to Pressure Load for 1" (25.4 mm) Aluminum Cans 1. Can with weak closed curl. May not leak if deformed, depending on crimping pressure and amount of deformation. 2. Can with strong open curl. May not deform enough to increase possibility of leakage. 3. Can with strong closed curl. A non-leaker from the standpoint of curl deformation. A. Machined curl cans with deformation curves lying to the right of this dotted line should not leak. Others are bad or uncertain. B. Non-machined curl cans with deformation curves lying to the right of this dotted line should not leak. Others are bad or uncertain. to 460 pounds (130 to 210 kg) and major deformation of the bead must not take place under these conditions. The difference between minor and major deformation of the aluminum can bead is illustrated in Figure 37. In order to prevent collapse of the rolled can bead under crimping pressures the metal should be of adequate thickness and temper and fully curled. An open or partly curled bead will tend to resist crimping pressures up to about the 300 pound (136 kg) level. It will then collapse slightly—to allow the bead to become fully curled, with the cut edge biting against the metal at the throat of the can. After a plateau of resistance against still higher pressures, the bead will then finally collapse, as shown in Figure 37. In the case of can beads weakened by over-machining (or polishing), this area of the structure will collapse, followed by the same type of plateau; and then a secondary, more complete collapse, again as shown in Figure 37. FEA Standard X-404 E describes a procedure for taking such measurements. Typical results are shown in graphic form, Figure 38. These same general considerations will also apply to tinplate and C/CO plate beads, except that much less work has been done in this area, and none has been published to date. Production of Aluminum Aerosol Cans The manufacture of single-piece aluminum aerosol containers starts with the melting of an 1100 series aluminum ingot; e.g. 1100-F. The purity has been described as 99.0 to 99.8%. The liquid aluminum at about 1290°F (700°C) is poured from a gas-fired or electric melting furnace through a special trough and onto a chilled casting wheel in order to produce a thick, continuous strip of metal. The slab is then rolled to the desired thickness. Aluminum cans that are tall in comparison to diameter require thicker strips. For instance, a standard \XA" (38mm) x 55/]6 " (135 mm) can requires a typical strip thickness of 0.410" (10.4 mm). The final rolled slab is lubricated, usually with a bacterially inhibited emulsion of about 3 % cutting oil in water, and then passes into a blanking machine, where anywhere from six to twelve dies punch out round aluminum slugs. The slugs are of the regular bowl- shaped design and generally have a preformed button of metal in the center to facilitate smooth extrusion later on. They are about 0.015 to 0.020" (381 to 508 fan) smaller in diameter than the proposed container so that they will fit readily into the press. After first passing them through an annealing furnace to soften them for can extrusion, they are tumbled in a cylinder to smooth any rough edges and are then re-lubricated and loaded into an automatic hopper leading to a 200-ton (181 metric ton) flat-bed or vertical impact extrusion press. Table XXIV Approximate Compositions of Aluminum Alloys Used In Aerosol Can Manufacturing Element Aluminum Iron Magnesium Manganese Copper Titanium** Lead Silicon Boron** Other metals 99.5% Grade 99.50 min. 0.30 0.01 0.01 0.02 0.02 max. 0.02 max. 0.10 0.01 max. 0.01 99.7% Grade* 99.70 min. 0.18 max. 0.01 max. 0.01 max. 0.01 max. 0.02 max. 0.01 max. 0.05*** 0.01 max.. 0.00 'Preferred for pharmaceutical and certain toiletry uses. *'Titanium and boron are added if necessary, to give TiB2 (titanium IV boride) for grain development in the alloy. "*"The maximum value is 0.10%.
The Technology of Metal Aerosol Containers 87 The press shank or piston slides through die die and strikes die aluminum slug widi tremendous force, causing the metal to flow up the side wall between shank and die. A mechanical stripper removes the hot extruded tube, after which the side wall is accurately trimmed to the desired length. The tubes or tall cups then pass to the necking machine, where a series of dies progressively form the top contour, including the bead. The cans are then led through a three-stage solvent bath for complete degreasing. In some instances the tubes or tall cups are further formed by a drawing operation, and in addition some aluminum alloy blanks are stamped and then drawn. The classical drawing-and-ironing process (as used in the manufacture of the former Apachecans of aluminum and also tinplate) led to the most accurate control of wall thickness and thus the greatest economy of metal. However, the overall economy was poor and the method was discontinued for aerosols in 1981. Linings The aluminum metal must be protected from the product (or vice versa) in some cases, and for this reason many cans are internally sprayed with either an epoxy phenolic or Organosol enamel. The epoxy type is much more common. The Organosol is thicker, more expensive and somewhat more protective. After spraying, the cans pass through a long pre- heater oven to cure the lining. The epoxy is applied as a clear liquid, but this cures to a golden or even yellow- brown hard film. Most Organosol linings are dark gray when cured. The integrity of spray-coated enamels in monobloc aluminum cans is far superior to that in most tinplate containers since there is no subsequent bending or welding operation. The manufacturers routinely check for possible voids by filling the lined can with a mildly acidified 10% copper (II) sulfate solution. In case of bare aluminum exposure, the solution will plate copper quickly on the metal, which shows up as a reddish-brown stain. Decoration Normally, aluminum containers receive an exterior coating of epoxy enamel, whether they eventually are lithographed or paper labeled. Some manufacturers include the base of the can in this operation, but others lack the equipment to apply a 100% base-coating. Without the coating, the bare aluminum metal will turn Figure 39. Slugs Used in Making Aluminum Drawn Cans The slug with the hole in it is used for the American Can Company 202x406 two-piece "Mira-spra" and "Mira-flo" cans. slowly a dull or dingy gray, due to the protective oxide coating that forms as a surface layer. The base-coat is applied either with automatic spray equipment or by roller coating the metal. After thermal curing the base-coated cans are brought to an offset lithographic printing press for final decoration. The Rutherford machine is a common type in the U.S. A. It can print up to four colors at once. The machine has four "color stations". At each location, several rollers are used to pick up and smooth out the various inks, after which they are transferred to zinc lithographic plates etched from the customer's art work. In a complex process, the inks are applied to four printing cylinders and then to a single printing blanket. The blanket is made of thin rubber. The four inks are perfectly registered onto it, so that there is no overlapping, mixing or layering. Finally, the blanket is used to simultaneously kiss print all the colors onto the base- coated aerosol can that is rolled across it on a turning spindle. The printed matter is then oven-dried. To complete the process, the delicate printing is sprayed with a coating of clear epoxy lacquer, which is then heat cured. In addition to offset printing, or instead of it, some manufacturers are able to provide brushed and textured effects, pearly, glossy, matte and transparent lacquer finishes, gold and silver blocking and special coatings for iridescent effects. Halftones are common in Europe and Japan. One alternate is silk screening, where a special nylon fine-mesh screen is photographically cut to the desired format in a process not unlike that used for photoengraving. An inking station spreads the liquid colorant on the back of the screen, so that it oozes through the
88 The Aerosol Handbook open areas. The can is rolled against the front of the screen and picks up the design. Further steps involve the optional registered addition of a second color, heat curing, application of the top enamel and final curing. Silk-screening has limitations in terms of number of colors and design complexity. It is also rather expensive. But it is useful where relatively small production runs are involved. Another alternate to offset printing is Thermiage transfer. The design is applied to release coated paper placed on a carrier device. The container is decorated by pressing the hot carrier against it, using a heated roller. This interesting procedure can be used to apply up to five-color rotogravure printing. Half tones and other process art can be added likewise. A clear coating of top enamel protects the delicate printing from abrasions or other damage. Texturing or texturizing is a popular process, although not a particularly common one in the U.S.A. In Europe many hair spray products are sold in large textured aluminum cans with gold or silver metallic finishes. In the most simple texturing process, the raw metal is wire-brushed or otherwise abraded and then clear epoxy coated for protection. The more elegant aluminum tubes may contain a so-called wedding band neck with a matching full- diameter cap so that the package has a full cylindrical appearance. These components are produced by the progressive drawing of thin aluminum sheet using an eyelet process. They are decorated by enamelling, texturizing, gold or silver dye lacquering or buffing. The relatively high cost of making and applying these fitments has held down their acceptance. Plastic caps in a huge variety of shapes, thicknesses and decorations are used more commonly, especially for large cans. Relatively similar techniques are employed in the manufacture, lining and decoration of two-piece aluminum cans, such as the American Can Company's "Mira-Spra" and "Mira-Flo" containers and the 46, 52 and 65 mm diameter containers by Metal Box Co. Some two-piece cans, such as those by Metal Box Co., are only made with tinplate ends. This gives them a substantial manufacturing economy, and also allows the filler to use standard magnetic handling equipment instead of engaging in a puck handling operation. However, the electrochemical dissimilarity between steel and aluminum may cause local bridge cell formation where the solution is capable of conducting a current. The more active aluminum may then be corroded. For the typical 52 mm (2.047 ") diameter Metal Box Co. can, the aluminum shell is 0.460 mm (0.018 ") thick through the wall and 0.016 mm (0.040") thick at the I. insect fepefe I Spray | ' © - u —J r ^ _ zz ;-2 no no :^ E= i /' ™ r ^ 1 £ ■ // Figure 40. A selection of 15 monobloc aluminum decorated aerosol cans by Metallemballasje, A.S., Norway, packed in a 14"X18"(350mmX450 mm) corrugate display case as samples. Can sizes range from 58 X195 mm (365 ml) to 22X68 mm (21 ml).
The Technology of Metal Aerosol Containers 89 Additional information regarding paper or foil labeling of aerosol cans is provided later in this chapter, where such things as preferred grain direction, wrapping and paper weight are discussed. Figure 41. Unique Aluminum Tube-in-Can Delopment Photo shows a tube-in-can development marketed by Aerosol Service, A.G. of Mbhlen, Switzerland, in which a flanged, very thin aluminum tube is filled with product and dropped into the one-inch (25.4 mm) or 20 mm opening of a drawn aluminum container (Both openings shown here). A thin rubber gasket separates flange and bead. The unit is then gassed and clinched or crimped (in the case of the ferrule type valve). The unit may be used for liquids, lotions, coarse sprays and pastes. shoulder. The tinplate base has a thickness of 0.28 mm (0.011"). Label Dimensions and Print Areas Unlike tinplate cans, which can be lithographed throughout the entire body wall height, aluminum aerosol containers are necked in and otherwise contoured at the top by processing them in Guzzi or similar machines. These curved areas can be base-coated and varnished, but they cannot be printed or paper labeled. The manufacturers provide literature giving the size of the printing area for their various cans. Typical specifications are shown for Metal Box Co. one-piece and two-piece cans in Table XXV, and for two monobloc Peerasol cans in Figure 42. In the case of wrap around paper or foil labels the flat vertical length of the can body is determined using a ruler. This dimension, less about lhe" (1.59 mm) for drift, can be used for the vertical label size. The horizontal dimension can be determined by wrapping a thin strip of paper around the can to get the circumference. An overlap dimension of about Vi " (12.7 mm) is then added, to give the overall length of the label. Corrosion Aspects of Aluminum Cans Aluminum can be rather unpredictable in terms of corrosion. With one limited exception, aluminum can- makers will warranty only good workmanship. Unlike tinplate manufacturers, they will not provide typical one-year warranties against corrosion or other forms of incompatibility. Aluminum is a very active metal, readily taking on a tenacious film of inert aluminum oxide when exposed to air. This gives rise to a rather unique and complex set of corrosion properties. For example, aluminum cans are corroded by both pure water and pure anhydrous ethanol, but not by many mixtures of these solvents. Figure 43 indicates the general corrosion activity of water/ethanol solutions, but must be regarded as semi-quantitative at best, since J0.500'l — *1min. f~ PRINTING AREA AND OTHER DIMENSIONS FOR TYPICAL PEERASOL CANS PRINTING AREA FOR LITHOGRAPHED CAN 7/8" x 3" PEERASOL TUBE wrrH 20 mm FINISH (STYLE 10-2) DIE SHEET O.S97- 1. 004 ^ AT 1*1.500 ±0.005"-»J f , . \ . = . i* ^f . "0" PRINTING AREA FOR LITHOGRAPHED CAN 1 1/2" x 4 3/16" PEERASOL TUBE WITH 1" (25.4 mm) FINISH (STYLE 50-2) ^5 DIE SHEET Figure 42. Printing Area and Other Dimensions For Typical Peerasol Cans
90 The Aerosol Handbook 0 20 40 60 80 100 PER CENT BY VOLUME OF ETHANOL IN WATER Figure 43. Corrosion pattern of water/ethanol solutions in aluminum aerosol cans (semi-quantitative only) so many factors are involved, such as air, temperature, pH value and other ingredients. Water or ethanol can be prevented from attacking aluminum by the addition of acidic substances, such as carbon dioxide or acetic acid. Aluminum is remarkably resistant to acids in general, often due to passivity. It is resistant to acetic acid at all concentrations, and even to strong nitric acid, although no more than traces of these substances should ever be used in aerosol formulas. While the metal is not attacked by ammonia or other weak bases, the addition of stronger alkalis could be disasterous. For example, if an aluminum can, lined or otherwise, were to be used to prepare a typical oven cleaner (which contains a few per cent of sodium hydroxide) the reaction: Al° + 6NaOH - 2Na3A103 + 3H2 (gas) would be anticipated, and the can would either leak at the crimp or simply rupture as the ultimate result of hydrogen gas overpressurization. Table XXV Label Dimensions and Print Areas For Aluminum Cans Made by Metal Box Limited Commercial Description One-Piece Cans 067.035 084.035 105.035 125.035 130.045 145.045 200.045 235.045 Two-Piece Cans 140.046 135.052 215.052 295.052 360.065 475.065 595.065 Nominal Dimensions l.S.O. Diameter x Overall Height (mm) 35x75 35x95 35 x 120 35 x 140 45x95 45 x 105 45 x 150 45 x 165 Diameter x Height (to shoulder, mm) 46x95 52x67 52 x 103 52 x 140 65x110 65 x 145 65 x 180 Overall Height (mm) Tolerance ±0.5 mm 76.2 96.0 120.1 139.7 95.0 105.0 140.0 165.0 102.0 76.2 111.9 148.8 122.4 157.9 192.8 Design Area Length (mm) Excluding Overcap 108 108 108 108 140 140 140 140 142 166 166 166 207.5 207.5 207.5 Maximum Height (mm) 65 85 110 129 70 83 118 140 91.5 63 95 136 106 141 176 Courtesy of Metal Box Limited Notes: Essential details should be at least 2 mm (0.079") inside the maximum design area. Where background color or horozintal bands overlap at the junction, the design area should be increased by 2 mm (0.079"). The label height, including tolerances, should not exceed the recommended maximum design area height.
The Technology of Metal Aerosol Containers 91 Many chlorinated solvents should never be formulated in aluminum cans. Propellent-11 (CCI3F) can decompose to produce hydrogen gas in certain anhydrous compositions. If ethanol is present also, it becomes particularly active, forming hydrogen, acetyl chloride, aluminum chloride, hexachloroethane, Pro- pellent-21 (CHCI2F) and other products as the result of a free radical reaction. The addition of water and a bit of acid may eliminate this reaction, but in any case, extreme caution is advised. The Dow Chemical Co. has advised particularly against the incorporation of their Aerothene TT solvent (inhibited 1,1,1-trichloroethane) in formulas designed to be marketed in aluminum containers, or even in those that contain aluminum powder, such as certain aerosol paint products. A large number of substances act as corrosion promoters for aluminum containers. As a rule, they are least effective for highly purified (99.8 + %) aluminum, more so for various aluminum alloys used in canmak- ing. Chloride ion is a strong promoter, especially in acidic media. Even trace quantities exert a major effect, and this applies to bromide and iodide ions as well. Oxidizing agents should be avoided, such as copper ion, peroxides and traces of hypochlorite ion. Rather surprisingly, certain reducing agents, such as sulfurous acid, formic acid, esters and aldehydes can bring about corrosion, but this may involve reactions by which the aluminum reduces the reducing agent; e.g. transforms an aldehyde to the alcohol. Fluoride ion is said to be an inhibitor, and many of the usual inhibitors used for tinplate cans have been found to be useful in aluminum containers as well. Because of die complexities surrounding die compatibility of aluminum and various aerosol formulas, each formulation should be tested specifically for many months in die suggested lined or unlined aluminum can before being produced in commercial quantities. Aluminum and tinplate can be used together with greater freedom from corrosion than might be anticipated, when considered from the dissimilar metal electrochemical standpoint. Tinplate bottoms are used often to lessen costs and facilitate can handling by avoiding die necessity of pucks on die production line. Tinplate valve cups also are used commonly widi aluminum containers. In some cases, tinplate cans are fitted widi aluminum valve cups to increase dieir resistance to attack by aggressive formulas, such as distincdy acidic products. Production of Aluminum Aerosols Most captive and contract fillers can handle aluminum cans that use a 1 "(25.4 mm) closure. The 13 mm and 20 mm types are filled normally on' 'Tube and Bottle Lines", since a special clinching machine is required to pinch in die ferrule of die valve so mat the junction widi die container becomes air-tight. To produce die clinch, a radier large and cosdy collet, about 6" (15.2 mm) long and carrying 16 to 24 tines, is brought down over die valve ferrule and die tines are dien strongly pinched inward, using a sliding mandrel sleeve. The ferrule wall is dius deformed, somewhat like die cap of a soft drink botde, in order to create die hermetic seal widi die can. For most production lines larger than laboratory scale models, aluminum (and glass) containers must be inserted into puck carriers — simply called "pucks". Odierwise the cans would tip over, fail to clear junction areas, float in all but specially designed hot tanks, and create odier serious problems. A typical 200 foot (61 m) production line, operating at 100 cpm, will require about 650 pucks, and another 10% should be on hand to allow for contingencies. Pucks are available normally widi eidier a magnetically susceptible stainless steel baseplate, or one or two small bar magnets attached to die bottom area of a polyethylene or polypropylene retaining cup. A phosphor-bronze spring clip is used often to hold the inserted container firmly in place. Each can diameter (and botde shape) normally will require a different set of pucks. Upon request, die puck supplier can provide pucks widi differently colored plastic shells to designate die container diat it is designed to accommodate. Two representative puck suppliers are State Manufacturing Co., Chicago, and Terco, Inc., Schaumburg, IL (See Company Listings). Aside from puck handling, a production line for 1" (25.4 mm) aluminum cans will have to have a special bottom coding device, sometimes special U-t-C gasser centering bells (as in die case of 2.089" (53.0 mm) diameter "Peerasol" cans), and perhaps special machines to apply such fitments as polished metal "wedding bands" when required. Extra large aluminum cans may pose problems for die standard aerosol line, simply due to dieir dimensions. Also, if they are over 26.8 fl. oz. (793 ml) capacity, a special DOT permit will be required for interstate shipments widiin the U.S.A. Next Page
The Technology of Metal Aerosol Containers Previous Page Many chlorinated solvents should never be formulated in aluminum cans. Propellent-11 (CCI3F) can decompose to produce hydrogen gas in certain anhydrous compositions. If ethanol is present also, it becomes particularly active, forming hydrogen, acetyl chloride, aluminum chloride, hexachloroethane, Pro- pellent-21 (CHCI2F) and other products as the result of a free radical reaction. The addition of water and a bit of acid may eliminate this reaction, but in any case, extreme caution is advised. The Dow Chemical Co. has advised particularly against the incorporation of their Aerothene TT solvent (inhibited 1,1,1-trichloroethane) in formulas designed to be marketed in aluminum containers, or even in those that contain aluminum powder, such as certain aerosol paint products. A large number of substances act as corrosion promoters for aluminum containers. As a rule, they are least effective for highly purified (99.8 + %) aluminum, more so for various aluminum alloys used in canmak- ing. Chloride ion is a strong promoter, especially in acidic media. Even trace quantities exert a major effect, and this applies to bromide and iodide ions as well. Oxidizing agents should be avoided, such as copper ion, peroxides and traces of hypochlorite ion. Rather surprisingly, certain reducing agents, such as sulfurous acid, formic acid, esters and aldehydes can bring about corrosion, but this may involve reactions by which the aluminum reduces the reducing agent; e.g. transforms an aldehyde to the alcohol. Fluoride ion is said to be an inhibitor, and many of the usual inhibitors used for tinplate cans have been found to be useful in aluminum containers as well. Because of the complexities surrounding the compatibility of aluminum and various aerosol formulas, each formulation should be tested specifically for many months in the suggested lined or unlined aluminum can before being produced in commercial quantities. Aluminum and tinplate can be used together with greater freedom from corrosion than might be anticipated, when considered from the dissimilar metal electrochemical standpoint. Tinplate bottoms are used often to lessen costs and facilitate can handling by avoiding the necessity of pucks on the production line. Tinplate valve cups also are used commonly with aluminum containers. In some cases, tinplate cans are fitted with aluminum valve cups to increase their resistance to attack by aggressive formulas, such as distinctly acidic products. 91 Production of Aluminum Aerosols Most captive and contract fillers can handle aluminum cans that use a 1 "(25.4 mm) closure. The 13 mm and 20 mm types are filled normally on' 'Tube and Bottle Lines", since a special clinching machine is required to pinch in the ferrule of the valve so that the junction with the container becomes air-tight. To produce the clinch, a rather large and costly collet, about 6" (15.2 mm) long and carrying 16 to 24 tines, is brought down over the valve ferrule and the tines are then strongly pinched inward, using a sliding mandrel sleeve. The ferrule wall is thus deformed, somewhat like the cap of a soft drink botde, in order to create the hermetic seal with the can. For most production lines larger than laboratory scale models, aluminum (and glass) containers must be inserted into puck carriers — simply called "pucks". Otherwise the cans would tip over, fail to clear junction areas, float in all but specially designed hot tanks, and create other serious problems. A typical 200 foot (61 m) production line, operating at 100 cpm, will require about 650 pucks, and another 10% should be on hand to allow for contingencies. Pucks are available normally with either a magnetically susceptible stainless steel baseplate, or one or two small bar magnets attached to the bottom area of a polyethylene or polypropylene retaining cup. A phosphor-bronze spring clip is used often to hold the inserted container firmly in place. Each can diameter (and botde shape) normally will require a different set of pucks. Upon request, die puck supplier can provide pucks widi differently colored plastic shells to designate die container that it is designed to accommodate. Two representative puck suppliers are State Manufacturing Co., Chicago, and Terco, Inc., Schaumburg, IL (See Company Listings). Aside from puck handling, a production line for 1" (25.4 mm) aluminum cans will have to have a special bottom coding device, sometimes special U-t-C gasser centering bells (as in die case of 2.089" (53.0 mm) diameter "Peerasol" cans), and perhaps special machines to apply such fitments as polished metal "wedding bands" when required. Extra large aluminum cans may pose problems for die standard aerosol line, simply due to dieir dimensions. Also, if they are over 26.8 fl. oz. (793 ml) capacity, a special DOT permit will be required for interstate shipments widiin the U.S.A.
92 The Aerosol Handbook Commercial Aspects of Aluminum Cans Aluminum cans are generally more costly than corresponding tinplate cans, even though they are only about 50 to 60% as heavy. This is due to the much higher cost of aluminum, which reflects the great amount of energy needed to produce the metal. A recent statement by Alusuisse suggests that 28% of all aluminum is now recycled, at an energy cost of 5% that needed to produce the virgin metal, so this may help the cost situation somewhat in the long range. In India, aluminum cans are extruded or drawn using metal produced in that country from their extensive bauxite deposits. To protect the industry, an importation tariff of about 250% is levied against tinplate cans. As a result of this artificial economic situation India's small aerosol industry now uses a great preponderance of aluminum containers. With rare exceptions, such as the Tube Manifold cans, the tinplate and steel containers lie within a capacity range of 3.4 to 26.8 fl. oz. (100.5 to 793 ml). Aluminum cans are not subject to these limitations, and can extend from 0.3 to at least 45 fl. oz. (8.9 to 1,520 ml). The smaller sizes compete with glass, coated glass and plastic for such products as perfumes, breath fresheners and medicinals, while the larger sizes are used for industrial and institutional products, such as dairy barn insecticides. The seamless aluminum containers often can be decorated with strikng impact. The use of silver and gold blocked decors, burnished finishes, brushed textured effects, iridescent metallic dye painting, wedding band and matching cap closures all contribute to suggest that aluminum cans may, at a price, be embellished with today's most sophisticated and beautiful decorative techniques. Such firms as the Risdon Manufacturing Co., and AndBro, Inc. specialize in high quality custom decoration. Their capabilities often may extend significantly beyond those of the aluminum can manufacturer. Despite the extra expense and delay, they should be considered when a particularly elegant container is needed. Aluminum is often able to hold products quite corrosive to tinplate. This may relate to the unique properties of the metal, or the ability to line the can completely with up to four or more coatings of enamel without any seams or bridging problems to contend with, as would be the case with tinplate. Also, since it is incapable of rusting in die standard sense, aluminum cans will not leave rings of corrosion product as stains in a wet or humid environment. Aluminum cans can be developed into packages of a simple cylindrical design, but tinplate welded and double necked-in cans can come very close to this ideal. Aluminum cans may be produced widi a certain degree of contouring. So may tinplate cans, but normally at a much higher cost, unless the sales volume is enormous. Both aluminum and tinplate cans can be used for inner- container barrier-pack systems. At uiis time, only the seamless aluminum can is fully adaptable to piston packaging, akhough welded tinplate cans may be developed with uiis capability within a year or two. These special container types are described later in this chapter. Stainless Steel and Other Aerosol Containers A very small market exists for stainless steel aerosol cans, particularly in the half to one fl. oz. (15 to 30 ml) range. They have die "S-type" 20 mm finish, because the alloy would tend to crack if worked into a bead finish design. These units obviously are expensive and can be justified for use only with costly products that are sensitive to aluminum metal, for example, a few delicate pharmaceutical items. These cans are available from die Virjune Manufacturing Co., Emson Research, Inc. and perhaps other firms. Large stainless steel aerosol cans of the returnable type are still available. They cost in the area of $7.00 each, in the 14 to 19 fl. oz. (414 to 562 ml) range. They are one piece units made by electrowelding top and bottom sections, followed by grinding and polishing. A typical application is for whipped cream dispensing, since they can be charged with up to 400 psig (2.76 Pa) and will then deliver a superior, fluffy product when dispensed. Most of Eric Rotheim's early aerosol cans (1922) were made of heavy-walled brass shells, brazed together at the center. Some twenty years later, some experimental cans were made of brass and bronze by Westinghouse. But the properties and relatively high cost of these copper alloys was never conducive to commercialization, and with one possible exception occur- ing in Eastern Europe, such aerosol cans have never been made in quantity. At present (1982) aerosol cans, except those of pure 99.8% aluminum, contain up to four metals. For example, a high lead, high strength, soldered tinplate can will contain iron, tin, lead and either silver or
The Technology of Metal Aerosol Containers 93 antimony. CHher metals are present in die steel alloy; e.g. Type MR steel contains a maximum of 0.20% copper. As a logical extension of tin and CCO plated steels the can companies have experimented with clad plate: LCDD and ether steel alloys coated widi nickel, monel metal or even aluminum. These metals are fused to the steel using special techniques, after which die plate is rolled to the final diickness. One of these metal companies, after rolling to a 100 lb. baseweight, might consist of 0.001" (25.4 m) of monel, 0.008 " (203 m) of steel and 0.002 " (50.8 m) of monel. The heavier monel coating would be designed to go against aggressive products. In practice, however, die high cost of clad plate effectively prevented its use for aerosol cans. Some clad valve cups were used about 1972, but in very limited quantities. They cost about as much as stainless steel valve cups and very few products could afford such exotic packaging luxuries. Figure 44. Some Tall Commercial Aerosol Cans Illustrated are some of the tallest commercial cans of their respective diameters. The unit at left is a 207.5x1113 "bazooka-type" made in France for hair sprays and other products. The large dark can is made by Hi-Pac Co.. for industrial applications and is returnable. It has been used for mineral oil based egg coating sprays. The other two are a 211 x 908 FIK insecticide by The d-Con Company, and a 300 x 709 spray foam rug shampoo by Carbona Corporaiton. The Paper Labeling of Aerosol Containers Aerosol cans may be decorated directly upon die basecoated metal, using a number of techniques mentioned earlier, or by using paper labels. Paper or foil labeling is used for about one tinplate container in five; more rarely in die case of aluminum cans, except in die larger sizes. It provides diese unique advantages: a. Warm, elegant feel. b. Ideally suitable for short runs, especially under 25,000 units. c. Can be decorated in every imaginable combination of colors, metallics, half-tones and shades. Foil laminates provide an extra measure of gloss and other effects. d. Labels may be embossed or debossed for special effects. e. They cover die welded side seam slag line and soldered area of three piece cans. f. They can be overprinted to provide distributor information, even in the case of very small productions. Similarly, such diings as pharmaceutical expire dates, slot codes, coupon deals and so forth can be applied to existing label stocks. g. They can be used to mask obsolete or defective liuiography, so uiat die value of die aerosol can (up to $0.49 each for tinplate 300 x 709s in 1981) can be salvaged. h. They help minimize inventory costs — important for firms widi cash flow and warehouse limitations. ® Uimen 4*t . I V II.1 When ordering paper labels it is vital to specify correct dimensions of paper and printing, as well as other criteria. In the case of tinplate cans made in die U.S.A., suggested dimensions are shown in Table XXVI. For aluminum cans, diese same concepts may be used, referring also to die manufacturer's recommendations for label height, as indicated in Table XXV and Figure 42. Reduced heights can be used for aluminum cans if desired, but for three-piece regular cans, labels should fit radier snugly between die double seams. Paper labels should be made of reasonably good stock running about 60 ± 10# in thickness. Individual preferences may differ, but it is generally considered uiat die grain should run the long (horizontal) way of die label for minimum labeler losses. When die grain runs die long way, wetting die back of die label widi water will cause it to curl into die longest possible tube.
94 The Aerosol Handbook The glue lap position should be specified to the supplier. Most often it is located at the left hand margin. Slight champfers are used occasionally at the corners opposite the lap area. They act to reduce the unsight- liness of sharp edges visible on slightly spiraled labels. Most labels are packaged in bundles of 1000 (sometimes 500), and preferably with heavy cardboard at top and bottom, using moisture resistant paper. They should be shipped packed tightly in sturdy corrugate, or even wooden cases, to minimize "dog ears" and odier problems. Any labels remaining in opened packages should be resealed to prevent curling due to humidity. Depending upon dimensions, composition (foil- faced, etc.), packaging, size of the production run, condition of the paper labeler, expertise of the operator, glue selection and other factors, label losses will run between 2 to 5%. In rare cases they may get to 15% or even cause shut-down of the production line. Paper labels have a series of disadvantages, summarized as follows: a. Labeling operations may reduce line speeds by 3 to 10%, dius increasing filling costs. b. They have rather limited water resistance, although foil-faced labels are better, and should not be used where they can become wet and wrinkled. c. Considering die overall AQL (Acceptable Quality Level) of the finished aerosol unit, the use of paper labels often has a mildly depressing effect on quality. d. Embossed and foil-coated labels are very expensive when purchased in relatively low volumes. e. During use, paper labels may absorb grease, grime and dirt, making the label unsightly. In addition to regular paper labeling, paper labels may also be attached to cans (and bottles) as window panels, metallized medallions, bottom discs (often giving the name and address of die manufacturer, net weight, code or other vital data) and (rarely) as a cover for special plugs or valves fitted into die base section of compartmented or piston aerosol cans. In some cases, they may be wrapped around the top inch (25.4 mm) or two of the can, or around the side wall of the cover cap to provide the purchaser with a coupon, a contest ticket, or some special information. Spot labels are sometimes affixed to the top of covercaps using contact adhesives, in order to give the retail store a place to print the price or to embellish die otherwise plain upper portion of the dispenser. Lithographic Decoration Lithography is used on about 80% of tinplate cans made today, and may be expected to become even more popular if the fledgling trend toward necked-in cans continues. Many aluminum cans are also lithographed, especially the smaller sizes. The procedure for developing a final lithographed can is outlined as follows: a. The crude label is developed and checked for compliance with existing government regulations. b. The sketch is provided to commercial artists for Table XXVI Specifications for Paper Labels Used for Steel and Tinplate Cans Dimensions Capacity (ml) Length Height, av. Height, max. Total length of printing* Length of live matter Length of Gloss Coat * Includes V8 " bleed 24 oz. 300 x 709 793 9"/l6" Vki" 7%" 9%6" 9'/16" 9Vi6" area under 5/b ' 20 oz. 211 x 713 649 8%" 715/16" Vk" 8%" 8%" 8%" 'lap. 18 oz. 211 x 612 564 8%" 6'%2 " 67,6" 8V«" 8%" 8'/e " 16 oz. 211 x 604 523 8%" 52%2" 5'5/l6" 8V4" 8%" 8% " 16 oz. 207.5 x 701 493 8% " 62%2" 6%" Vk" Vk" Vk" 14 oz. 211 x 510 472 8 V 5%2 " 55/16" 8'/4" 8%" 8'/8" *'Two 14 oz. 207.5 x 605 443 8Vs" 531/32 " 6" Vk" Vk" Vk" ■piece drawn car 12 oz. 211 x 413 403 8%" 5'%2 " 5'/2 " 8%" 8%" 8%" 1. 12 oz. 207.5 x 509 386 8Ve " 57/32" 5V«" Vk" Vk" Vk" 12 oz. 214 x 411* 368 97.6" 5"/,2" 5%" 8'%6" 8"/16" 8"/16" 12 oz. 202 x 708 398 7%2" 7%2 " 73/16" 621/,2 " 6'732" 6'7,2"
The Technology of Metal Aerosol Containers 95 final designing, which leads to a product called "artwork" in the trade. c. After approval by the marketer, the artwork is processed by the canmaker into "black and white proofs" (actually blue and white, today). d. The proofs and color swatch samples are then approved by the marketer and the can supplier then prepares "press plates", using contact negative photoengraving techniques. e. Unless they happen to be made at the same location, the press plates are then forwarded to the lithographing can plants, where the cans will be manufactured. Marketers often ask the can companies to supply "Color Tolerance Booklets" for their cans. Each booklet contains a set of three can bodies in the flat, showing the lightest, the average and the darkest color combination the canmaker proposes to supply. These booklets are sometimes used by the quality assurance department of the marketer or contract filler in order to maintain reasonable color uniformity of the finished lithographed plate. In addition to standard lithography, done in the flat, dry offset lithography and other processes may be used to decorate containers that have already been formed; e.g. aluminum cans. Silk screening is an option, where short runs are planned and only one or two colors are acceptable. %' JfAlR ^■WOVER > 1 Figure 45. Plain and Lithographed Aerosol Cans A plain, white enameled Crown Cork & Seal Company 6 oz. "Spra- tainer" ready for either silk-screening (rare) or paper labeling, compared with a comparable lithographed can of GONE, a hair remover foam, with an obsolete 5.3 fl. oz. fill declaration. During the latter 1960s tinplate bodies were sometimes embossed about 0.004 " (100 /im) so that the metal could be used to highlight and accentuate printing designs. This practice has now been discontinued. Various textured designs have appeared, where extra thick areas of the print coat are used to create a marginal three-dimensional effect. In some cases the Table XXVIB Nominal size Dimensions Capacity (ml) Length Height, max. Height, aver. Total length of printing** Length of live matter Length of gloss coat 12 oz. 211 x 411* 387 87e" 47.6" 4'%2" 8%" 8'/6" 8'/e" 10 oz. 207.5 x 413 336 8%" 4376«" 43'/6«" 7Ve" 7'/2" 7'/2" 11 oz. 202 x 700 372 7732" 6"/,6" 62l/32" 62'/32" 6'%2" 6'%2" 9oz. 202 x 509 287 7732" 5'/4" 5%2" 62I/32" 6'%2" 6'%2" 7 OZ. 202 X 406 223 75/32" 4V,6" 4'/32" 62,/32" 617/32" 6'732" 6 oz. 202 x 411* 216 7732" 37.6" 3'%2" 62,/32" 6'%2" 6"/32" 6 oz. 202 x 314 197 7732" 3l7,2" 3V2" 62'/32" 6"/32" 6'%2" 5 OZ. 113 X 411 176 6 V 47,6 " 4-732" 574" 57e" 57e" 4 oz. 202 x 214 144 7752" 27.6" 2"/32" 62l/32" 6'732" 6'732" 3 oz. 202 x 200 98 7732" l"/.6" l2'/32" 62,/32" 6"/32" 6'732" * Two-piece drawn cans. * 'Includes Vs " bleed area under % " lap
96 The Aerosol Handbook appearance of texturizing can be achieved by the use of color combinations, as in some matte and leatherette finishes. The durability of modern lithographic decorations allows the can maker to utilize several types of metal- working techniques on the body, such as double seam bending, necking-in, and can forming operations. The decoration survives these procedures remarkably well. On the dome, such decorative finishes as, clear lacquer, base coat and varnish, and base coat, print and varnish may be applied before the progressive die-forming operations that turn the flat disc into the finished contour. Dome printing should be applied in terms of short and simple words, such as "Shake Before Use" (never "Shake The Can Before Using"), so that the user can read the precaution without turning the can around totally. Also, the words may drift somewhat, since the metal stretches unevenly when going through the die press. The words should never be underlined, since this merely highlights the waviness problem. Container Shaping The now defunct Hunter-Douglas Co. in California was perhaps the first aerosol manufacturer to produce shaped cans. About 1957 they produced 202-diameter aluminum units in a variety of contours. Some failed, such as accordion-shaped cans, which "grew" during hot tanking as a result of the high internal pressures that were developed. Most were well designed and were offered to an industry that was simply not ready to accept them. During the mid-1960s the Boxal Sales Division of Alsuisse provided conies, Gibson Girl (narrow-waisted) and other cans, but they were rarely seen in the European markets. More recently, the firm has introduced well over twenty contoured aluminum cans, some customized and others available from stock, all with the upper portion especially shaped to provide a high degree of individuality, as shown in Figure 26 and the Brut 33 cans, Figure 30. The first contoured tinplate aerosol cans were produced by the Continental Can Co., using their elec- troforged Cono-weld side seam units. By the year 1969 the technology had been developed at Continental Can Co. 's R&E Center in Chicago for what was termed the "Electro-hydraulic Can Forming Process", in which the lithographed can body was placed in a shaping mold and filled with a sturdy rubber cylinder, containing a pair of electrodes and some electrolyte solution. Sufficient current is passed through the electrodes to produce a known amount of hydrogen gas, sufficient to expand the sealed rubber diaphragm very hard against the can body, forcing the metal outward to assume the contour of the shaping mold. The gas is then released and the mold opened to remove the expanded can body. This method is suitable only for expanding the body several per cent beyond the nominal double seam diameter. It was never used to any extent in the aerosol industry as things turned out, mainly due to extra costs involved. Several molds had to be prepared, and the cans were made more costly due to this added production step. However, the process was used to make a popular beer-barrel shaped 12 fl. oz. beer can during the early 1970s. Continental Can Co. has since used several other can shaping methods, in one notable instance providing inwardly shaped cans for a large antiperspirant marketer. The economics of aerosol marketing programs later caused a reversion back to the standard cylindrical container. Shaping may be applied to the low-temper bodies of tinplate and CCO welded cans, but not to drawn or drawn-and-ironed tinplate cans, unless the high temper is first relieved by annealing. This added treatment would be too costly to consider seriously. Many designs give rise to contoured cans that have a special panel for the product trade name. Whenever the contouring is of this type (not homogeneous around the can body), the lithographed can will have to be registered accurately in the mold before shaping. Also, during shaping, the can wall is often pulled toward the shaped area, generally more in one place than another. This means that shaped can bodies must then be trimmed to length, necked-in (as a rule) and flanged, before assembling the end units. Other options have been used occasionally to try to convey contouring to aerosol cans, even to the extent of fitting the aerosol entirely within a plastic outer container, as in some products marketed during the 1970s in Italy. Various shapes can be suggested for plastic overcaps, particularly those which fit over the top double seam of necked-in cans. A line of antiperspirants sold in England was distinguished by a cover having a ball-like shape, giving the product a rather perspicuous phallic silhouette. In rare instances, the impression of contouring has been achieved by using plastic snap-on fitments that go over the bottom double seam. However, they are a direct extra cost item, tend to com-
The Technology of Metal Aerosol Containers • I 97 \ ii 4ITOX "J ??££. Figure 46. Exploded Aerosol Can Due to Fire/Heat The cleaned body and base sections of an aerosol dispenser that had been placed in a fire and heated until the pressure of the contents everted and then blew off the dome. Figure 47. Cut Away of Three-Piece Soldered Can A three-piece soldered side seam can opened for inspection of the interior surfaces to check for possible corrosion. Shown with a can of NU-TOX insecticide (made in 1960s) bulged to an unusual degree before the body split, when thrown accidentally into a fire. plicate packaging, and add to shelf space requirements if they flare outward. In one unique instance, a decorator base of metallized plastic was used to snap onto a necked-in bottom double seam and extend upward to cover the bottom 25% or so of the can with a delicate filigree design. As the aerosol industry moves into the 1980s, many of these cosdy decorations are being set aside in favor of the simple, straight cylindrical approach. Aerosols already suffer somewhat from an over-packaging image, and products that deliberately add obvious luxury tend to be passed over by an increasingly economy minded public. Aerosol Can Safety Devices Even though empty cans and bottles are non- combustible, all too often aerosol dispensers have been disposed of by incineration. Despite precautionary instructions there are reports of aerosols tossed into the backyard burn-barrel, an apartment house incinerator, or large city refuse treatment centers. They may be overheated by exposure to furnaces, stoves, sunlight or other forms of thermal energy. One large car maker measured 265°F (130°C) in the glove compartment of a black automobile, in a set of "worst case" conditions. Another measured a still higher temperature in the heated air emitted by under-seat car heater pipes. Any or all of these conditions are sufficient to cause ordinary aerosol cans to evert and then burst. Table XXVII provides an indication of the pressure rise in aerosol units when exposed to high temperatures. In ordinary three-piece tinplate aerosol cans, when overheating occurs dome eversion will result, then base inversion and finally rupture, as the top or bottom seam unwraps and one of the ends blows off. In some cases, the base will evert first, or the dome will evert and separate before the base inverts. Quite rarely, the body metal will bulge and then tear apart before the ends separate. If a soldered side seam is involved, it will fre- quendy soften in a fire, causing rupture to occur at that location before anything else happens. Many exploded aerosol cans will be found to have bodies with significant bulging. The two photographs illustrate aerosol cans where significant body bulging took place, prior to rupture. Table XXVII Pressure of Various Aerosols At Elevated Temperatures Aerosol Pressure (psig) Spray Starch Spray Starch Air Freshener Temperature (5% A-31) (5% A-31) (31% A-46) °F °C Air-Free (20 "Hg° Vac. Cr.)* Air-Free* 100 120 140 160 180 200 38 49 60 71 82 93 59 84 111 153 181 223 65 91 119 162 191 235 80 110 147 191 243 305 "As percent head space decreases the incremental pressure of air rises, due to greater reduction of the head space when adding the propellent. *Example considers a minimum head space, thus minimizing preferential evaporation of propane as the dispenser is heated, yet without liquid filling the dispenser, even at 200°F (93°C).
98 The Aerosol Handbook In the case of two-piece tinplate or aluminum aerosol cans, the end section normally bulges out and then separates. For Monobloc aluminum cans, the valve generally loosens to allow gross product leakage. In some cases, it blows off when the pressure exceeds about 400 psig (2.76 MPa). In a few cases, aerosol cans will vent through the valve hole in the cup, after the plastic portions of the valve have melted or burned away in a fire. Cans that are emptied of all but a few grams of the product cannot develop excessive pressures when strongly heated. After the last of the propellent has turned into the gaseous phase any further increase in pressure will be slow, more or less in accordance with Charles' Law. Such cans may still explode, first as a result of solder softening and creep, or in the case of welded or seamless cans, when the can metal becomes hot enough to be significantly softened. For example, most steels lose about half their strength when heated to 950°F, and soften rapidly after that. There is no real agreement within the industry as to how serious the problem of can bursting is, from a consumer safety and property damage standpoint. No reliable records have been kept. At a recent gathering of industry experts, it was estimated that there may be as many as 2 to 6 aerosol explosions per year in the U.S.A. that have serious health and safety consequences to people. This averages out to about one disfiguring, life threatening or possibly lethal accident for every 500 to 600 million units sold... a safety record better than that of over a hundred other commodities commonly found in the marketplace. Other sources suggest a higher rate of injuries. About 1970 a survey of 600 U.S.A. insurance companies was conducted by the U.S. Department of Health, Education and Welfare. On an annualized basis, they reviewed 10,328 closed product liability claims and found eight which specified aerosol explosions; e.g. 0.77%. A similar survey covered 2,500 physicians, who handled 12,750 product related injuries in a two-week period. Three involved aerosol burns to the upper body, but it is not known if the burns were caused by bursting aerosol cans or by ignition of the sprayed contents. The National Electronic Injury Surveillance System (NEISS) was started in July, 1969 under HEW and later transferred to the Consumer Product Safety Commission (CPSC) in the early 1970s. Although the industry has been strongly opposed to the interpretation of results, nevertheless, in one survey period lasting 19 months and covering 244,938 injuries, Table XXVIII Critical Pressure Ranges for Tinplate and Aluminum Aerosol Containers Dot Container Specification DOT Specification 2N** (tinplate and CCO) DOT Specification 2P (tinplate and CCO) DOT Specification 2Q (tinplate and CCO) (NCC Experimental Can - 165# ends.) Small Aluminum Cans (Standard wall) Small Aluminum Cans (0.030 "min. wall) Dome Eversion 150 - 170 170 - 190 190-210 320 - 350 n/a. n/a. Typical Pressure Range (psig) Base Inversion 160 - 180 180 - 200 200 - 225 No data None Minimal Bursting 220 - 245 245 - 275 275-310 430 - 465 375 - 500 800 - 1250 Bursting Temperature of Typical Starch Can** 200°F 211°F 220°F 265°F — — •U.S. Department of Transportation Tariff No. 6000-A (1981). "The example given in Table XXVII, with 5% A-31 and a 20" Hg° (-69 kPa) vacuum crimp. "'Sometimes called a non-specification can. Note: Standard European aluminum cans have 12 bar (174 psig) test pressure and 14.4 bar (208 psig) burst pressure minimums. High strength ones have 16 bar (232 psig) test pressure and 19.2 bar (278 psig) burst pressure minimums.
The Technology of Metal Aerosol Containers 99 only five cases were related to aerosol explosions. Most can explosions result from throwing aerosols into fires. The backyard incinerator or burn barrel, the inside fireplace, a pile of burning leaves or refuse fires can all quickly overheat aerosols and cause them to rupture. Representative pressure ranges for dome ever- sion, bottom inversion and can rupture are given in Table XXVIII, along with typical contents temperature at the time of rupture, using an aerosol starch with A-31 (isobutane) propellent as an example. Pressure relief devices to protect aerosols from thermal rupture have been the subject of well over 200 U.S.A. Patents over the past 30 years, and studies in this complex area are still in progress. Most of the work has been done by the can manufacturers, but aerosol valves have also been an active area. Out of all this effort, only three devices were ever commercialized; two of them in such miniscule quantities, they can almost be discounted. The only device of importance is the Rim Vent Relief (RVR) can dome modification developed about 1969 by the American Can Co. and later licensed to other can manufacturers, including the Continental Can Co., where it is called a Pressure Relief Mechanism (PRM). The very limited number of available pressure relief devices available presently is due largely to the combination of economic, aesthetic and performance requirements that have had to be met. Some of these are summarized as follows: a. The cost of the safety feature must be absolutely minimal, since the consumer will not normally recognize it and will have essentially no interest in the commodity if the price is out of line with that of comparable products. Most consumers feel they are able to handle aerosols safely and will pay nothing extra for a safety device, since they consider it unnecessary in their case. b. The device must be essentially foolproof in its operation. If the dispenser can still explode, the marketer may have to suffer the legal consequences of having lulled the consumer into a sense of complacency by installing the safety mechanism. If, on the other hand, the dispenser may sometimes be caused to spew out its contents prematurely (for instance, at too low a temperature), then the marketer may have to face torts where injured parties attempt to recover damages to property. This is especially worrisome now that about 90% of all aerosols contain hydrocarbon gases fully capable of causing detonations, if they escape and ignite in closed areas. c. The safety device must not look unsightly or otherwise interfere with the saleability of the product. d. The device must not interfere with the assembly or operation of the aerosol package. e. As a part of the economic consideration, the device must not force the canmaker to use extra- heavy plate, conduct many extra quality assurance tests, slow down the speed of his production lines or do anything else that would increase the price of the empty can. If integrated with an aerosol valve, the same concepts apply. f. The mechanism must not act to reduce the quality or performance standard of the finished unit. g. The safety device should work (ideally) on all types of aerosol dispensers. h. The unit should shut off (again ideally) the discharge of product when the pressure is reduced to safe levels. As it turns out, the device that is the most promising by far is the RVR type construction. This unit meets an average of five of the eight criteria. The pragmatic overall rating is about 75%, or perhaps 80%, if only tinplate three-piece cans are considered. Because of these aspects, the safety feature is now used on only 4 or 5% of all aerosols made in the U.S.A. The earliest safety feature was a fusible plug of Lipowitz' Alloy, melting point 160°F (71°C), or some other solder composition set into the.floor of the valve cup. Due to unreliability, inadequate discharge rates, cost and other factors this attribute has been almost totally discarded. Perhaps the next important innovation was the hardened steel spike, developed in the mid-1960s by Cornell Aeronautical Institute at government suggestions. The final system involved poising a sharp spike directly above the countersink trench of the dome on three-piece cans so that, when excessive pressure caused dome eversion, the spike would puncture the metal and release the overheated product. In practice, the spike was very unsightly. In operation, it filled up most of the hole it punctured in the dome, allowing rather slow release of the can contents; so slow in fact, that many cans could be exploded by continued heating, even though the pressure relief mechanism was operating.
100 The Aerosol Handbook The "Beard Clip", which is really a modified spike, was developed by Walter C. Beard in the late 1960s. This hardened steel, U-shaped litde accoutrement could be literally clipped onto the top double seam and could be expected to gouge a big hole in the dome when mat section everted under excessive product pressure. It was somewhat unsightly and a bit costly as well. Modified clips were designed for use along the bottom double seam, but in this case at least three were needed or the can would be off-balance. The various "Beard Clips" saw almost no use in production of aerosols. About 1970 the now defunct Sterigard Corp. (in California) developed a rather expensive "Safti-Pac" valve spout, designed to vent cans when the pressure increased high enough to overcome the tension on a sealing spring. It never moved into production. Even now, in 1981, work is progressing in at least two locations with the aim of creating a double-acting, pressure relief aerosol valve at a minimum upcharge. During 1968 and 1969 the American Can Company performed the major portion of their development work at Barrington, IL on what is still the only viable method for preventing the bursting of overheated three-piece aerosol cans. It involves the incorporation of a pressure activated safety feature, the Rim Vent Release (RVR), into the top portion of the top double seam. In the original design, a typical 211-diameter can dome is made with twelve radial scorelines, about lA " (6.4 mm) long and evenly spaced around the periphery. Those scorings are made in a press, where a die squeezes the dome metal down to a prescribed thickness in each of the indentations. The seaming elastometer is then flowed in and cured, after which the completed dome is Figure 48. Original - Version of RVR O Aerosol Can r\ American Can Company F~: introduced the Rim Vent : Release (RVR) aerosol can P in the 1960s. The single !Z indentations are now | replaced with triplet inden- w , tations for better control. '„ rlESHIt • Kim seamed to the can body under carefully regulated conditions. After a period of a few years American Can Company determined that the pressing of slighdy smaller, shorter and shallower indentations on either side of the single previous one acted to control the temper due to metal working and made the mechanism more reliable. Safety device cans produced by American Can Company and their licensees still display this triple indentation design. When the RVR-type aerosol can is overpressurized the dome everts. Metal movement at the top double seam area allows the scorelines to crack open to form narrow, lense-like apertures, through which the product can exit rapidly. Leakage may occur even before total eversion takes place, usually at one or two locations, but if the pressure can still rise another 5 psi (35 kPa) or so, then total eversion will occur and all the central indentations can be expected to open and release either gas or product. The RVR-type containers appear to offer safe venting of three-piece aerosol cans under all situations, except those that involve direct misuse in violation of precautionary labeling instructions. During the 1970s a frequent complaint was that commercially empty cans, thrown into a fire, might undergo soldered side seam softening and rupture at that area before the internal pressure became high enough to cause dome eversion and RVR release of the product still in the can. In a very hot fire, some relatively full cans might build up pressure faster than could be discharged through the dome apertures, in which case the dispenser might explode. With the swing from solder to welded cans, the first problem is eliminated. The second one was investigated in 1980 and 1981 and found to be extremely rare. Problems that still exist are as follows: a. Cans will spew out their entire contents at the time of dome eversion, which will happen in the field with far greater frequency than rupture due to the much lower pressure (or temperature) required. Such things as pigments, strong solvents and flammable hydrocarbon propellents can then bring about secondary damage. b. The score lines on the dome are very visible and may show rusting if the can is stored in a moist environment. The newer, triple-scored domes have been viewed as an attractive embelleshment by some persons. The scorings are more visible in
The Technology of Metal Aerosol Containers 101 the case of white enamelled domes, least for dark gold lacquered domes. c. The safety feature may dilute the intent of precautionary labeling. The can companies have developed suitable alternate formats. d. The development is limited to three-piece containers. e. Can costs are increased about 1 %. f. RVR-type cans are significandy more hazardous in a warehouse fire than placebo cans. Cans do not fly around, but anhydrous escaping product from a multitude of cans produces a large, extremely hot fire, capable of producing structural damage to roof areas within a short time period. g. In a situation where some aerosols are the RVR- type and others are not, the consumer may not be able to differentiate between the two and think he has an "explosion-proof can, when in fact he does not. He might then take certain liberties in terms of storage or disposal that could cause the can to explode. h. Wide acceptance of the RVR-type can could impose very heavy costs on the canmakers, by forcing them to add a complex operation to each of their dome-forming lines. i. Wide use of the RVR-type system would put aluminum cans and glass aerosols at a marketing and product liability disadvantage, since it works only for three-piece units. j. RVR-type cans undergo dome eversion and product discharge within the 175 to 205 psig (1.21 to 1.41 MPa) range, whereas no aerosol can will normally burst below 220 psig (1.52 MPa). To compensate for this and reduce the statistical chance of product release under very warm storage conditions, the marketer must often choose between the use of a lower pressure formulation and a higher strength container—such as the DOT Specification 2P type. At least one government has recognized officially the safety aspect of RVR-type aerosols. In regulations effective during 1972, Canada required that a bursting symbol be prominendy displayed on the front panel of aerosols to warn the user of its potential hazard. However, if the dispenser has an approved safety device designed to prevent bursting, they agreed that the onerous symbol could be omitted. Marketer acceptance of the RVR-type container has been indifferent. Probably no more man about 100 million have been made in any year since they were introduced about 1970, and the number seems to be decreasing at the start of the 1980s. Rationales by marketers for using the special cans vary: dedication to safety, concerns about product liability actions, promotional campaign (for a direct selling or "wagon trade" concern), want the best possible product in every way, and so forth. The precautionary statement "Do not incinerate." should be retained on RVR-type cans, since long jets of fire can be produced when the dome section everts, at least for some formulations. These jets can injure persons standing close to backyard burn baskets, burn barrels and fireplace type incinerators. In fact, with the increasing numbers of refugees, the so- called "functional illiterates" and others with a below- average comprehension of the English language, some marketers are talking about revising the statement to ' 'Do not incinerate or burn.'' (Even though the English word "incinerate" is closely related to the Spanish " incineradar ".) Compartmented Aerosol Cans A number of compartmented aerosol containers are available. They are considered under two headings: those where the can is prefitted with a piston, inner cylinder or bag, and those where the compartment is introduced as an extension of the valve. Only the first variety is considered here. Perhaps the earliest piston can is the American Can Company's "Mira-flo" aluminum 6-oz. container, introduced in the early 1960s. The container itself is their "Mira-spra" 202 x 406 can, containing a plastic piston and a base section pierced with a small hole. The piston is made usually from a particular polyethylene alloy. The skirt is about 1.5" (38 mm) long and is designed that way to minimize "blow-by" of lower viscosity products, to prevent possible tilting and to Figure 49. Base section of aluminum monobloc can flared inner portion of the rubber plug showing
102 The Aerosol Handbook negate the effects of small body wall dents, which might otherwise allow the gas to slip past the piston and form bubbles in the product itself. See Figure 51. During the early years the sales of "Mira-flo" cans were inhibited because of the difficulty of gassing the can through the bottom % " (3.2 mm) hole and then plugging it under sealed-system conditions with the end of a reel of rubber rod about %4 " (3.6 mm) in diameter. Complex laboratory scale devices were produced by the canmaker, and finally some production size gasser- pluggers were developed. After that, sales began to rise. During the early 1970s, a modification of the European Varnley Valve was developed in order to simplify the gassing process, but nearly all "Mira-flo" cans are still gasser-plugged. The combined sales volume of the "Mira-spra" and "Mira-flo" cans totals about 30 million units per year from American Can Company's plant at Regency, PA. However, since there are only two major marketers using the "Mira-flo" can, information on the sales volume of this particular unit would be too revealing of the marketer's sales. The "Mira-flo" dispenser is useful only with products within a certain viscosity range, generally about 10,000 to 500,000 cps., as measured at room temperature, using a Brookfield Model RVT Viscosimeter with Spindle No. 7 at 10 rpm. Since nearly all the possible products are non-Newtonian fluids, the conditions of measurement have to be delineated for reproduce- ability. A variety of cheese spreads and cake toppings are currendy marketed in the "Mira-flo" unit. Many other products are possible as well, such as hand lotions, petrolatums, mayonnaise and toothpastes. On the other hand, certain likely candidates have failed, such as peanut butters, where most compositions undergo syneresis under pressure, with the vegetable oil separating slowly at the top and leaving an exceptionally high viscosity peanut grind as the lower stratum. Figure 50. Polyethylene piston used in "Mira-flo" aerosol can. The diameter is about 2.00" (51 mm). Historically, the only other piston can has been American Can Company's "Flo-Master" container, a drawn 211 x 413 tinplate can that was introduced about 1969 and discontinued after several years because of disappointing sales, plus the Pepo unit, described later in this chapter. The Sepro-Can The Continental Can Co. introduced their "Sepro- Can" development about 1967, with the thought that it would expand significantiy the aerosol industry by adapting the aerosol principle to permit the dispensing of higher viscosity products; e.g. those in the 10,000 to 2,000,000 cps. range, measured with a Brookfield RVT at S.#7 and 10 rpm. under ambient conditions. The first units consisted of a 202 x 406 can with an interior plastic bag of either modified polyethylene or "Conoloy", a special plastic alloy of relatively low permeation rate. The side walls were pleated, like an accordion, so the bag could collapse upward as the container was emptied. The top of the bag curled outwards, fitting neady over the can bead. The can itself was radier routine, except that the plug diameter of the usual one-inch (25.4 mm) opening was expanded to about 1.025 " (26.0 mm) in order to make room for the plastic bag. Also, a V8" (3.2 mm) hole was punched through the center of the bottom to allow for gassing and plugging. "Sepro-Cans" sold for a premium of about 55 % over the cost of the non-compartmented can of the same size. A typical "Sepro-Can" of 1970 is shown in Figure 52. During the first few years several changes were made in the bag contour, giving it a more wavey or "sine- curved" profile, since the original sharp pleats often caused gas voids when die concentrates were added. When the gas bubbles emerged during actuation, uiey expanded with sharp splats, sometimes spattering the product in the process. The company also added a 202 x 509 can size and a 202 x 200 sample can. They also produced samples of "Sepro-Cans" in die 211 x604 container, but no market ever developed. The 202 x 509 dispenser eventually became die most common size by far. In this case, the bag capacity is about 7.02 fl. oz. (207.6 ml) with the valve in place. An additional 1 or 2 % of product can be filled if the concentrate is added at temperatures of about 40°F (4.4°C), depending upon die thermal expansion coefficient of the product. At room temperatures, die capacity of the bag for die 202 x 509 can is about 74% as large as the overall can
The Technology of Metal Aerosol Containers 103 capacity of 9.71 fl. oz. (287 ml). This compares rather favorably with the average aerosol fill of about 85% of can capacity, especially when the liquid hydrocarbon propellent outside the bag is also included. In terms of volume fill, the penalties for using "Sepro-Cans" is a small reduction in fill size, and the fact that the net weight will have to relate to one bag-full of the product. It is impossible to overfill a bag without spilling the excess, and underfilled bags have the spattering effect mentioned earlier. The net weight of "Sepro-Cans" must now relate to the weight of concentrate that can be dispensed from the bag, about 96 to 98% of the weight in the lowest net weight bag in twenty representative samples. According to NBS Handbook No. 113, published in 1981, there is no longer a weight allowance of about % oz. (3.5 g) to compensate for the difference in results of the fast discharge test method and the slow discharge process used by the average consumer. The allowance has been retained only for foam aerosols. As such, it probably cannot be considered to apply to the gelled (post-emergent foaming) shave creams that now form the bulk of the "Sepro-Can" filling business. A major potential problem with "Sepro-Cans" and, in fact, with all plastic bag-in-can dispensers is the phenomenon of permeation. Permeation takes place when significant numbers of molecules pass through a barrier during a fixed time period. Larger molecules permeate more slowly than small ones. More permeation takes place at higher propellent pressures, simply because there are more molecules in contact with the barrier. Molecules with higher solvency ratings tend to pass through more effectively than inert types. The gross effect of permeation is that "Sepro-Can" concentrates tend to become slighdy aerated upon aging. Ingredients in the concentrate may also pass through the bag into the propellent phase. For example, acetic acid in a packed mayonaisse product seeped uirough the bag and severely attacked the unlined can, causing perforations. P-l 14 (sym-dichlorotetrafluoroethane) is perhaps the ideal propellent for slow permeation performance. It is a large molecule, with very slow solvent powers. The fluorocarbons P-l 15 (monochloropentafluoroethane) and Freon C-318 (perfluorocyclobutane) offer comparable peformance but are very high priced. The smaller P-l2 molecule permeates bag walls somewhat more rapidly, and the regular hydrocarbon gases (propane, isobutane and n-butane) more rapidly yet. In most cases, strong solvents permeate too fast to be used. As a result, P-ll (trichloromonofluoromethane), Figure 51. A typical early "Sepro-Can" made by the Continental Can Company in 19/0. The inner bag of the "Sepro-Can" is a one-ply structure. Shown at right is a cross-section of the system. Compatibility of product with the plastic bag must be considered when developing product formula. methylene chloride, dimethyl ether and certain perfume aldehydes should be tested thoroughly before approval. Carbon dioxide, nitrous oxide and even compressed air have been suggested for "Sepro-Can" systems, but they have the distinct shortcoming of having no liquid reserve to draw upon. Thus, the propellent pressure decreases markedly during use. As an ancillary consideration, there is also no reserve against slow or latent seepage, either through the bag or through the can itself. Even after some 14 years, the "Sepro-Can" inner bag is still a one-ply or non-laminate structure. Efforts have been made to coat the bag with films of Mylar or other plastics having very low permeation, but the engineering problems have been too intense for a practical solution. Gassing has always been a general problem with "Sepro-Cans". Special equipment is needed. The earliest versions required a gasser-plugger, which tended to restrict filling to only a few contract fillers who had the needed engineering skills to develop such a production device. Then, in the early 1970s, the cans were introduced with the Nicholson Model 55-18 valve (fashioned rather like a football or basketball valve) that fitted through a somewhat enlarged hole in the can
104 The Aerosol Handbook bottom. It accepted both liquid and gaseous propellents at very high rates, allowing single-head gassing stations to operate at up to 30 cpm. For still higher speeds the rotary Kartridg-Pak "Under-the-Cap" (U-t-C) could be used by adding a special gassing head under the elevator plates. However, a major problem with the original Nicholson valve was that exact positioning of the gassing tube under the center of the valve was required to avoid tilting or otherwise distorting the valve stem, causing either immediate or latent leakage of the propellent liquid. To correct this problem a special, solid rubber plug was developed by Continental Can Co., first used commercially about 1971. It is known as the Nicholson No. 2 valve. This inexpensive, one-piece fitment is technically a rubber billet, partly splined vertically on the side wall, and stuffed part way into the hole in the bottom of the can by the can maker. The filler then uses special equipment to force propellent past the splined slots and into the exo-space Figure 52. Kortridg Pak's "Sepro-Can" Unit for Under- the-Cap (U-t-C) Gassing (between bag and container), after which a small ram forces the valve further into the can until the splined portion is totally inside and a gas-tight plug is produced. Additional U-t-C change-over parts were necessary to convert the machines to the revised plug. The conversion unit is shown in Figure 53. The '' Sepro-Can'' is well suited for the dispensing of relatively viscous products, those in the range of 2,000,000 cps. at room temperatures. Both Newtonian and non-Newtonian types can be handled. While there is no difficulty in dispensing low viscosity products (up to 10,000 cps.), as a rule these types can be handled in the lower cost standard aerosol packages. "Sepro- Cans" have been tested with regular, low-viscosity shaving cream emulsions. The standard aerosol package produces a heavy, wet, slighty runny foam near the end, due to propellent loss from the emulsion into the enlarging head space. With the "Sepro-Can" this modest problem is eliminated. On the practical side, it has not been enough of a problem to justify the added packaging cost of using a compartmented can. Even a metered foam product would become only about 1.5% more concentrated near the end of the can, so that "Sepro-Can" packaging cannot reasonably be justified for pharmaceutical or dosage-type foam products any more than for shave cream types. A single exception is the gel-type shaving cream. In products on the U.S.A. market in 1981 offered by two major marketers and being developed by others, the gelled concentrate contains a few per cent of isopen- tane. This propellent has a boiling point of 86°F (30°C), so that then the gel is worked or slightly warmed, it blossoms into an elegant, highly lubricious foam structure. If the isopentane is to be incorporated into the gel during the batchmaking process, it is necessary to produce it under cold conditions, such as 40°F (4.5°C), in order to prevent the inadvertant generation of foam at that point. Spin fillers are then used to transfer the concentrate gel to the fluted bags, for instance a Consolidated Packaging Machinery Corp. 18-head Spin Filler or various Elgin Packaging Machinery Corp. models. The containers can be twirled around at from about 400 to 1200 rpm, in order to facilitate getting the product into the plastic flutes without air entrapment. However, if the spinning rate is excessive, a vortex will develop in the center. Optimum spin speeds must be developed according to the properties of each concentrate.
The Technology of Metal Aerosol Containers 105 During 1981, some 30 million "Sepro-Cans" were produced in the U.S.A. Nearly all of this volume was dedicated to the latent foam gel shave cream products, but other items of a cosmetic nature were filled as well. The cans were gassed using two Kartridg-Pak Co. 9 head U-t-C fillers (modified), three Terco, Inc. Sepro Chargers (40 cpm capacity), and at least three custom- built machines of limited throughput. As an indication of cost, the Terco device runs about $14,000 complete, for the 202-diameter cans. Products that have been commercially packed in the "Sepro-Can" include a moisturizing cream, depilatory cream, shaving gels (for both men and women), caulking compounds, a tomato catsup, natural honey, toothpastes and an interesting ablative gel designed to thermally protect precious ringstones during resizing of the band. A number of products have also been considered, for instance, such food type items as chocolate syrup, ice cream toppings, soft drink super-concentrates (good for up to 100 8-oz. drinks), maple syrups, jellies, and mayonnaise. But the concept of an expensive container that did nothing but dispense the standard produce proved uninspiring to consumer test panels, and the projects were dropped in every instance. The Presspack System During 1978, the Presspack Corp. of Bronxville, NY combined forces with the Southern Can Co. to introduce their new Presspack System to the aerosol industry. An interesting "Doubleheader" package was offered. It consisted of a double necked-in 202 x 509 "Slim-Look" can with Southern's "Aeroweld Super Seam" construction. Each end was fitted with a can dome, measuring a 1.998 ± 0.004" (50.75 ± 0.10 mm) across the double seams. Two specially shaped translucent polyethylene bags had been inserted into the can body before end seaming, and after the ends were attached, the flared lip of each bag was pulled through the one-inch (24.5 mm) opening. The cut edge at the top had an average diameter of about 1.160" (29.5 mm), allowing it to hug the can bead at least as far out as the crown area. The bags had a neck finish thickness of about 0.012 " (0.53 mm) and this required the can domes to have a plug inside diameter of about 1.048" (26.6 mm) and an outside bead diameter of about 1.242 " (31.5 mm). The bags varied in thickness from about 0.028 " (0.71 mm) at the throat to as thin as 0.009 " (0.23 mm) at the body wall bulges. They had a capacity of about 4 fl. oz. (118 ml) and each was filled with a different cosmetic product. To insure a gas tight seal between the can and the 0.14 " (0.35 mm) thick lined aluminum cups, a standard 0.040 " (1.00 mm) thick rubber cut gasket is placed over the can bead before crimping. Crimp dimensions of 1.070 " (27.18 mm) diameter and 0.190 " (4.83 mm) depth were recommended. The use of valves with GK-45 or similar flowed-in gaskets was specifically not recommended, since the typical 0.22" (0.56 mm) elastometer thickness is insufficient to bridge the 0.015" (0.38 mm) step between gasket and can bead at the outer rim of the polyethylene bag flange in order to create an effective secondary seal. The "Doubleheader" unit was principally designed as a sales give-away product, and had little or no commercial significance. The regular unit looks much like a regular 202 x 509 can, and normally has a single shell, full diameter Risdon Corp. cover cap to complete the cylindrical appearance. In cooperation with Kartridg-Pak, the Presspack Corp. has developed recommended gasser adjustments to convert for the U-t-C gassing of their "Presspack" barrier units. Either a compressed gas at the desired pressure of 115 psig (793 kPa) or so, or about 2.5 to 3.0 g of a hydrocarbon propellent may be used as the propellent. For example, for the addition of a liquified propellent by either the in-line or rotary U-t-C equipment, the following steps must be undertaken: a. Relax collet pre-set adjustment b. Replace pressure pad spring with solid washers or stops to give negative inner bell lift. c. Set head in fill posiiton with a }4 " (8.3 mm) spacer under can to be filled. (No valve in can.) d. Set for propellent charge of about 2.5 g and propellent pressure of about 400 psig (2.76 MPa). e. To allow for dwell time in filling cycle, reset vacuum timer to operate during the fill cycle. (Inline machines only.) f. Set for crimp diameter of 1.070 " (27.18 mm) and crimp depth of 0.190" (4.83 mm). Use standard molded cap seal. Prefer undimpled valves. The "Presspack" dispenser is said to be thoroughly researched and proved out in terms of millions of cans produced commercially with at least 25 product types. Nitrogen or compressed air propellents are preferred. Such forms as pure liquids, pastes, gels, foams and
106 The Aerosol Handbook > Deli tody ■/ / Figure 53. Bag-in-Can System Offered in Europe A "Compak" depilatory container, illustrating the bag-in-can system offered by Aerosol Service AG, Switzerland. The design is contrived to give the cylindrical container the appearance of being contoured. creams can be dispensed with the container held in any position. Emptying efficiency is up to 99% of the bag contents. There is a slow permeation of the bag material by various propellents, and this may cause some aeration of the dispensed products. The Alupresspack System Starting about 1978 a European development took place, with the creation of a barrier pack startingly similar to the U.S.A. "Presspack" development. The ) 1.30" (33.0 mmLa— j0.97"(25mm)f|>— Bag capacity 463 ml. with valve inserted. Aluminum can diameter: 65 mm. *2.11" (53.6mm)- Dimensions are typical. They are not to be used for specification development. Figure 54. Polyethylene Bag for Alupress-Pack Can European system provides for the exclusive use of an aluminum Monobloc aerosol can in the 1.575" (40 mm) to 2.559 " (60 mm) diameter range and the provision for adding the propellent through a hole in the can base, which is then sealed with a rubber plug. The invention is being successfully marketed by Aerosol Services, S.A. of Mohlen, Switzerland. The range of product sizes is from about 100 to 500 ml. In a typical product, a disinfectant spray is marketed with the formulation: 350 ml in a polyethylene bag: 80.00% Ethanol96v.% 0.40% Formalin (37% HCHO in water - inhibited; DAB 7) 0.01 % Alkyldimethylbenzylammonium chloride 90% 0.03% Glyoxal (40% C3H4O2 in water - inhibited) 0.01 % Oligo-di(iminoimidocarbonyl) imino- hexamethylene 20% 0.05% Perfume 19.50% De-ionized Water In the surrounding 65 x 212 (628 ml) aluminum can: 12.0% ± 2.0 g propellent. The spray is soundless and the dispenser can be operated from any position. There is no significant change in delivery rate during the life of the package. A sketch of the polyethylene bag is provided in Figure 51. The Microcompack and Alucompack Systems Both of these recent developments took place in Europe and are being marketed in the early 1980s by Aerosol Services, S.A., Switzerland. The "Microcompack" system utilizes an aluminum tube in the 5 to 15 ml range, fitted with a heat-softened, thin aluminum inner tube (cylindrical, with a flat base) that slides into the can rather snugly through the 20 mm opening. The diameter of the inner container is thus about 14.0 mm. It is flat-flanged at the top and seals against the beaded can opening with the aid of a cut rubber gasket that is only about 0.012 " (0.3 mm) thick. In the production operation, the inner container is filled with the product to within a short distance of the flanged top. The 20 mm aerosol valve, with a large- diameter plastic body, is fitted into the top of the tube, where the body acts as a sealing plug. Meanwhile, the empty can is filled with a few grams of extremely cold,
The Technology of Metal Aerosol Containers 107 u /> Figure 55. The Alu-Compack Composite Aerosol System This system is marketed by Aerosol Service, A.G. The illustration shows aluminum cans with and without base plugs, and how the aluminum inner tube collapses rather completely as the unit is dispensed. Both spray and foam type actuators are shown. Figure 56. Bag-in-Can Development from Switzerland A unique bag-in-can development, where the special polyethylene alloy container is inserted into an aluminum can, filled with product and attached to the special valve assembly. Hydrocarbon propellent is injected and the valve crimped into place. (Aerosol Service, A.G.) liquid propellent. The inner container is slipped quickly in place and the 20 mm valve ferrule clinched to the can, making a hermetic seal. This dispenser has been commercialized in Europe during 1980, using both hydrocarbon and chlorofluoro- carbon propellents — and possibly dimethyl ether. But in the U.S.A. a major stumbling block is the addition of highly flammable hydrocarbon liquid to an open container. A closed system gassing method is now available in Europe because of this problem. They gas the outer tube with the inner one about half-way inserted and then make the crimped or clinched seal under closed system conditions. The larger "Alucompack" system is designed along the same lines as the "Microcompack" version, but uses aluminum cans in the 30 to 35 mm diameter range, with standard one-inch (25.4 mm) opening. The inner tube or "Alu-bag" of heat-killed aluminum may now be about 0.992 ± 0.003" (25.2 ± 0.08 mm) in outer diameter, and again, may be only about Vi "(12.7 mm) shorter than the outer container. After filling with product, the inner tube is plugged with the mounting cup of the valve. An exploded view of the overall assembly is shown in Figure 59, in this case relating to a very unusual application. Most of these units are fitted with regular spray, paste or foam valves and are used for various pharmaceuticals and toiletry products. In the early 1980s a large toothpaste marketer has introduced one of his products in an "Alucompack" dispenser measuring about 1.2 " x 6.0 " long (30 x 152 mm), packaging it in an attractive shadow box. The unit is designed to stand upright, and obviously avoids the various problems inherent in the conventional tube, such as unsightliness and the need to roll it up during use. Marketers in the U.S.A. are studying this important innovation. They were unsuccessful in the case of the "nitrosol" Crown 202 x411 cans of the 1960s, and have seemingly been disenchanted in the "Sepro-Can" toothpastes marketed in small volumes during the 1970s. Aside from cost considerations, the toothpaste Figure 57. Alucompack System for Toothpaste Product A sophisticated dispenser of toothpaste, marketed in West Germany by Blendax. A vertical slit in the plastic actuator opens to dispense the paste when pushed sideways, then closes to prevent hardening or other exposure effects. Anfr UmpMU An«i
108 The Aerosol Handbook "of the 1980s" in "Alucompack" form may capture their interest. One highly intriguing aspect of the German product is the use of a dispensing tube that is rounded at the end, rather like a bullet-shape, and then slit longitudinally for a short ways. Upon actuation, the slit opens to provide the product, but when the toggle- action valve is released the slit closes tightly, keeping the toothpaste clean, soft and ready for the next use. The FLIP System The FLIP (Formed Liner In Place) aerosol system was developed by Dr. Tor Petterson, a professional inventor at Rancho Palos Verdes, CA, with patents issued and/or pending in several countries. The aerosol can is first sprayed or dipped to coat the interior with controlled release coating, such as a polyethylene/ acrylonitrile laminate, vinyl acetate/polyethylene/ polyimide laminate or acrylate/polyvinyl chloride composition. For three piece cans this operation is best performed before attaching the dome section. A base is used that is fitted with a gassing aperture, preferably using a gassing plug of the type now used for "Sepro- cans". As shown in Figure 60, the container is filled with product, sealed with a suitable valve and then gassed through the base. At least 30 ml of head space should be left in the can when filling the concentrate to allow for the later addition of propellent and also leave some Figure 59. Coating, Filling and Use of "Flip" Borrier Pack Cans Courtesy of Tor Petterson, I.D.S.A. COAT FILL CHARGE USE EMPTY W? Concentrate fc Valve assembly Thin lathe-cut rubber gasket Inner "Alu-bag" Propellent Aluminum Monobloc tube, 1.25" (32 mm) in diameter and 6.50" (165 mm) long. Thickness of valve cup and aluminum outer tube are exaggerated to emphasize thin "Alu-bag" component. Figure 58. Cross-Section of Alucompack Dispenser (Exploded view, showing typical valve.)
The Technology of Metal Aerosol Containers 109 space to take up any thermal expansions of product and gas that might occur prior to consumer use. When the dispenser is first used, the head space air is emitted quickly with a sharp crackling sound. After this the product emerges. As it does, the lower section of the can liner separates from die can wall and folds upward. Since it is only about 0.002" to 0.008" (0.05 to 0.20 mm) thick, progressive upward folding is not a problem. When the dispenser is commercially empty the lining will have folded to about mid-point of the can wall, as shown. The dispenser has been tested using propellent pressures of from 25 to 90 psig (172 to 620 kPa) with chlorofluorocarbon, hydrocarbon and compressed gas (CO2 and N20) propellents. Products such as pre- foamed shaving cream, toothpaste, skin cream, cough medicine and a caulking compound have all been tested satisfactorily for over two years. The dispenser will discharge at least 95% of viscous materials and a minimum of 97% of low viscosity liquids. Only about 4 to 10% of the inner coating is exposed to the propellent prior to consumer use. In addition, most coatings are laminates, so that permeation of propellent into die product is negligible. The system is being commercialized in Germany under a European license. The Enviro- Spray System The final barrier pack to be discussed in some detail is die. "Enviro-Spray", developed by inventor Ellis Reyner during the 1960s and taken over by Grow Group, Inc., Montgomeryville, PA, about 1977. After a long and costly refinement program, Grow Group introduced their first consumer product, "Like Magic'' Plant Spray during 1981 and also offered samples to interested marketers. The product is prepared using a special barrier pack that is dropped into the empty aerosol can before filling with concentrate and sealing with the valve. A combination of citric acid and sodium bicarbonate (or similar chemicals) is used to generate slowly gaseous carbon dioxide in the can, raising it to a pressure sufficient for efficient dispensing action. The gas remains widiin die expanded bag and does not mix with the product. As the product is dispensed, the bag becomes still larger, rupturing an inner wall and releasing more ■ chemical to form additional gas. This may occur several times during the life of the can, so that the gas pressure widiin the unit can remain reasonably uniform during use. The plastic pouch and its contents may weigh to 1 oz. (28 g) for a 16 oz. (454 g) fill. The dispenser is claimed to deliver 98% of its contents. For further information, refer to U.S. Patent No. 3,718,236 or Enviro-Spray Systems, Inc. at Montgomeryville, PA. Other Barrier Packs Around 1980 Boxal/Alusuisse introduced their "Compack" unit, representing a new type of barrier system where the gassing operation can be performed by forcing the propellent into the container between can neck and valve cup. This eliminates the need for a punctured can base and special gasser-plugger type operation. The plastic inner bag is secured to the valve tailpiece via a special polyethylene adapter. Either bubble or ridged sidewall plastic bags can be used and the unit can be adapted to all standard containers with a standard one inch (25.4 mm) opening. The bag must be the correct length for the can, since a preliminary inter- fit with die adapter is required before U-t-C gassing. At the time of gassing the pneumatic pressure forces the top section of the bag fully into the circular slot in the adapter producing a barbed, hermetic seal between valve and bag. During the late 1970s inventors Th. & H. Schumacker developed the "Pepo" ecological aerosol and formed S.A. Kervil, N.V. to promote the dispenser. The firm is located in Brussels, Belgium. The unit is a piston type, similar to American Can Company's "Mira-flo" container. The piston is somewhat unique in diat it has five fins diat wipe against the can wall. Fins two and three (from the bottom) have a diameter of typically 2.065 "(52.45 mm) and are very diin, so they can bend against the body wall. The bottom fin is typically 2.051 "(52.10 mm) and the two uppermost fins are each typically 2,039 " (51.80 mm). They are there to keep the 1.940 " (49.28 mm) tall piston aligned vertically so diat die two wider, sweeping Figure 60. Piston used in the "Pepo" ecological aerosol container promoted by S.A. Kervil NV, Brussels, Belgium
110 The Aerosol Handbook Figure 61. The "Preval" Spraymaker fins can act to separate gas and product portions. The second thin fin is also insurance against the co-mingling of phases, if the can wall has a slight dent that would distort one of the fins but not the other concurrently. The piston has a well in the top to accommodate the valve body. Samples are shown with a Boxal can and Valois valve. The propellent is compressed air, although liquified propellents should work even better, since they would maintain a constant pressure throughout package life. The propellent is injected via a gasser- plugger operation. Concentrates of the water-base and hydroalcoholic base have been tested successfully and other, non-warping types would seem reasonable candidates. The original "Preval" unit was introduced by the Precision Valve Corp. in 1965. The propellent in a power unit, typically a lithographed 1% " x 6 "(35 152 mm) aluminum tube, is used to aspirate product out of a separate container. After some disappointing initial results with filled products, which were able to leak out of the dip tube connecting them to the "Preval" valve, Precision Valve Corp. decided to sell only the dispenser with the product container empty. In the present form, a nominal 4 fl. oz. (118 ml) glass wide-mouth jar is used to contain the product. The black plastic screw cap is fitted with the'' Preval'' power unit, so that pressing the valve button creates a 99% vacuum in the valve, causing the product to flow up the common dip tube, be mixed with the emitted gaseous propellent and be discharged as a spray. The original dispensers contained P-12, but in the U.S.A. these have had to be revised to a hydrocarbon propellent with a consequent drastic reduction of filling weight to about 3 oz. (85 g) and some loss of capacity. At a typical dispensing ratio of about ten parts product to one part propellent, some 30 oz. (850 g) of paint, lubricating oil, cutting oil, sealants and other products can be handled during the life of the unit. The manufacturer sells a fair number of "Prevals" each year, mainly in retail outlets such as hardware and automotive supply stores. The final "barrier pack" is not really a composite aerosol but is included for completeness. In the early 1970s, Plant Industries, Inc. introduced their Selvac Division's "Selvac" dispenser, consisting of a posted heavy rubberized bag mounted within a formed can, plastic bottle or other rigid container. The bag was closed at the top with an aerosol valve, after which product was injected to fill the unit. In the unfilled form, the bag had an internal volume of only a few ml and when distended with (for instance) a pint (473 ml) of product, the resiliency factor caused it to exert a considerable pressure on the contents. This pressure was utilized to dispense the material. Some hand lotions and related products have been packed commercially using the "Selvac" system. During late 1980, three "Selvac" experts departed from Plant Industries, Inc. and formed Container Industries, Inc., Londonderry, NH. In the following year they introduced their "Exxel" elastomer package counterpart, claiming added design simplicity and other advantages. Several personal care and household products were test marketed in 1981, and such products as greases, creams, lotions, foams, gels are recommended for trials. The bag is non-porous polymer and can be manufactured from selection of several materials. Considering barrier packs in general, although they have been available for perhaps 25 years or so, the present interest seems to be on the increase. In 1981 it reached a sales volume of about 1.5% of the total aerosol productions of both the U.S.A. and Europe. This should continue to grow in the decade of the 1980s.
GLASS AEROSOLS We wish to thank Mr. Edmund Budzilek, consultant for Wheaton Aerosol Company, for his invaluable help in reviewing the manuscript on this chapter. 111 3 The earliest use of glass for a self-pressurized dispenser probably dates back to "Gebauer's Topical Anesdietic Spray," where a heavy glass tube contained ethyl chloride and the product was emitted as a thin stream when a spring-loaded rubber seal was removed from a pinhole orifice. By 1950, the Zonite Corporation introduced the first formulated product in glass aerosols: a mothproofing spray, based on the use of an aqueous solution of sodium silicofluoride, plus an insoluble chlorofluorocarbon propellent. The solution was far too corrosive to be packed in a metal can. The 16-oz. glass bottle was shielded from breakage by gluing it widiin a sturdy cardboard cannister. Aerosol fragrance products had been marketed by Lucein LeLong and others since 1949, but the cans were relatively unattractive, so in 1952 the Wheaton Glass Company (now Wheaton Aerosols Company) brought out several glass aerosols in presssure-resistant designs. Two-ounce (59 ml) and four-ounce (118 ml) sizes were most common, and the new containers were recommended for colognes, perfumes and medicinals. Unlike the previous products in 2-oz. (59 ml) aluminum cans and G^oz. (170 ml) "Spra-tainer" tin- plate cans, the glass packages were an instant success in die marketplace. A large number of special glass aerosol lines were installed by marketers and fillers alike, and soon these products made an important contribution to the hefty overall growth rate of the aerosol industry. The first Wheaton aerosol bottles were of plain soda- lime glass, sometimes with a follow-up surface treatment, such as acid-etching or sand-blasting for special decorative effects. The pristine glass units could withstand pressures in the 600 -1200 psig (4.14 - 8.28 MPa) range under static conditions, but were susceptible to damage by impacting forces. Although small plain glass aerosols and small to medium size plastic-coated glass aerosols are now recognized as eminently safe, in those
112 The Aerosol Handbook early days, with only plain glass bottles available, marketers were concerned that diey might burst through some mishap in the field, perhaps causing injuries to some of dieir customers. So they went to the glass suppliers and insisted that some kind of a protective coating be developed, one that would not diminish the aesthetic properties of the bottle, but would safely contain all die glass fragments in the event that breakage should occur. Wheaton developed such a composite container in late 1953. The sheath was composed of polyvinylchloride. The first plastic coated bottle was marketed by die Allen B. Wrisley Company in 1954. During the 1953 and 1954 formative period, glass bottles were produced by several firms: die Wheaton Glass Company, Maryland Glass Company, Foster- Forbes, Inc. and others. Wheaton remained the only producer of plastic-coated bottles for a number of years, until Owens-Illinois developed a modest line of twelve stock bottles during die 1960s. According to Commerce Department figures, die U.S. cologne and perfume aerosol market reached a unit sales volume of about 169 million units in 1973. Over half of diis was in glass and coated glass. The rest was in aluminum tubes. Pharmaceuticals, such as bronchodilators for inhalation dierapy, topical germicides and so forth were packaged in glass aerosols at die rate of about 11 million units per year. From diis, one may suppose that die market for glass aerosols approached 100 million units per year in die peak year of 1973, widi fragrance products comprising some 85% or so of diis volume. In 1974 die CFC/ozone controversy struck, and die market for glass aerosols fell away very rapidly, probably down to die bottom level of 20 million units in 1977, a decline of 75% or more. Very nearly all die lost fragrance product volume had been replaced by pump Figure 1. Glass Colognes The larger unit is "Cristal" eau de toilette 96% vol. by (Lesord of Paris. 4 Av. oz fill (Density is 0.96 g/ml) in a diamond-faceted aerosol bottle. Decoration is silk screened white on blue. Metallized PE cap has three vanes that compress against a 20mm ferrule. The bottle on ~ left looks like an aerosol but is a pump-spray. Jovan Musk Oil; 7/8 fl. oz. by Jovan, Inc. sprays, akhough a small fraction was transferred to aluminum cans. Following 1977, the glass aerosol industry started to grow slowly, on die basis of reluctant marketer acceptance of of hydrocarbon propellents for colognes and perfumes. It reached about 38 million units in 1980 (composed of about 17 million fragrance products and 21 million pharmaceutical products) and this increased to around 42 million in 1981. About 25% of aerosol fragrance products are now in coated glass bottles, but die figure is much higher for pharmaceuticals. About 13 million fragrance products were packaged in aluminum tubes in 1980. Considering pump-spray and true aerosol fragrance products in 1980, die pump-spray variety held about 87% of die unit volume. In most cases, diey look almost exactly like the plain glass aerosol version, akhough die lack of internal pressure permits die use of larger bottle sizes and more complex shapes. Container suppliers in 1982 were limited to die Wheaton Aerosols Company, Carr-Lowry Glass Company, and Brockway Glass Company. Wheaton is die acknowledged leader in volume sales and die only source for die plastic-coated glass aerosol units. The Wheaton botdes are produced by a Wheaton Industries plant some 20 miles to die east of the plastic-coating plant at Mays Landing, N.J. They are plastic coated on lines such as die big "E Line", capable of producing 105,000 to 120,000 units per workday. Manufacture of Glass Aerosol Bottles The general technology of glassmaking can be obtained from other sources. Once a blow-molding operation is ready, molten glass is led from the furnace to die bottlemaker as a yellow-white hot, radier viscous mass of metallic silicates, borates and oxides, and shaped into the form of the finished unit witiiin about five seconds. The mass immediately begins to cool. As it does, stresses build up as die congealed outer layer tries to compress die still molten mass within. These stresses must be quickly relieved if the bottle is to be usable. The newly formed botde is thus placed in an annealing lehr and reheated, to allow a satisfactory redistribution of force vectors. Then it is cooled slowly so there will be a minimum of stress concentrations present in die cool bottle. If die bottle is to be left uncoated, or if it is one of marginally acceptable geometry that could be marketed only in a coated form, it is subjected to a surface
Glass Aerosols 113 toughening process known to the trade as a "Hot and Cold End" treatment. At Wheaton this is called the SAF Process. The very hot, newly formed bottle is treated with an organic titanium complex or tin chloride in the vapor phase. Because of the residual heat of the bottle, the metal ion present in the vapor is reduced to the metal at or near the bottle surface. It then plates out upon the highly reactive glass matrix and is rapidly oxidized to the dioxide form, utilizing oxygen present on the surface. The resulting skin of metallic dioxide — or metallic silicate complex, depending upon preference — is substantially harder and tougher than the underlying glass. It may be as thin as 1 m/t. (4.0 x 10"8 inch), so that it is completely colorless and transparent, or as thick as 6 m/t. (1.5 x 10"7 inch), so that it can cause an optical interference effect resulting in a brilliant display of iridescent colors. To achieve the very best results, the oxide film is finally sprayed with a lubricant as the ware emerges at the cold end of the annealing lehr. Typical lubricants are polyethylenes, silicones and various stearate esters. The system of oxide and lubricant not only helps prevent accidental scratching but also minimizes adverse environmental changes of the glass surface. Sometimes, however, the system may bring about certain problems, such as loss of adhesion between paper labels and siliconized glass bottles. Three USP Types of glass are used for the manufacture of aerosol bottles: a. USP Type I. A borosilicate type glass, normally used for parenteral drugs — injectables. It is considered acid resistant and is very low in alkalinity. b. USP Type II. A soda-lime glass that has been treated with sulfur dioxide inside the bottle, to remove active sodium from the surface, resulting in a glass that is less alkaline than Type III but more so than Type I. c. USP Type III. The conventional soda-lime glass used most commonly for aerosol packaging and for glass packaging in general. Aerosols are made normally from Type III glass unless the product requires one of the other two USP types. Most uncoated glass bottles are made of clear, colorless glass. This material is a very poor ultraviolet light absorber. If the proposed formulation would be harmed by contact with ultraviolet light, the bottle must be made of amber glass, or it must be coated. Amber glass has been used for many years to afford ultraviolet protection to sensitive products, but even this glass transmits some of the wavelengths between 300 to 385 mu. The color also carries medicinal overtones and is therefore not particularly appealing to marketers of cosmetic products. The best approach is to use a coated bottle. By incorporating an organic ultraviolet screening agent, such as a substituted benzophenone, into a clear plastic jacket, it is possible to achieve 100% cut-off at wavelengths of 385 mu. and below (the high energy portion of the ultraviolet spectrum) and from 95 % to 97% cut-off at wavelengths from 385 mu. to 400 mu. in the visible violet range. After the bottle emerges from the annealing lehr, it is inspected for a number of visible detectible defects, such as: a. Seeds. Bubbles of gas in the glass. b. Stones. Undissolved inclusions. c. Marks. Imperfections on the glass surface. d. Checks. Tiny cracks in or on the glass. e. Misshapen Bottles. f. Leaners. g. Incompletely Blown Bottle. Anything which is not contributory to a perfect bottle may be considered to be a defect. In addition to the 100% visual inspection program, aerosol bottles undergo at least three special tests, conducted at specified intervals throughout the shift: a. Pressure Testing b. Compression Testing. c. Thermal Shock Testing. Ware produced prior to the production testing operations is quarantined until tested. Upon completion of a successful testing series the ware to that point is released and the next lot of quarantined ware is examined. Systems such as this help insure that a minimum of substandard ware will reach the field. Despite the care exercised by the glass manufacturer to maintain surface perfection, some marketers insist upon secondary decorating operations, such as ceramic or metallic decoration, acid frosting, or sand-blast surfacing. Metallic or ceramic decoration requires that the glass be heated back up to the strain point or beyond, in order to insure that a good bond is formed between the
114 The Aerosol Handbook 15,5'— -1^- Sr I JE- Figure 2. Dimensions; Finish of 20 mm Glass Aerosols glass and the decorative material. This requires another trip through an annealing lehr, plus considerably more handling, so that the possibility of damaging the glass surface is greatly enhanced. In die U.S.A. diere is essentially only one standard neck finish, or contour for the neck and top, whether die glass bottle is to be offered plain or with a bonded plastic coating. A typical finish is shown in Figure 2, for the 20 mm size. The finish is not standard. There is only tacit agreement among glass manufacturers to maintain the more critical dimensions. Outside the U.S.A. die non- bonded plastic coated bottle is still available and this requires an indented ring at the neck. During botde manufacture, blow molds are used which provide the glass with a circular groove directly under die lip of die unit. When the botde is plastic coated this groove fills with plastic, forming a thickened ring. When the metal valve ferrule is clinched down over this ring of plastic, the coating is effectively prevented from blowing off the ruptured bottle, even if the fracture involves severe damage to the neck area itself. About 60% or more of all glass aerosols in the U.S.A. is now plastic coated. Only die very small bottles for fragrance products are a notable exception. The interest in coatings is twofold: prevent injury from flying glass fragments by effectively containing diese shards should bottle rupture occur, and to prevent injury from the possible ignition of die hydrocarbon propellent and product by effectively containing the contents should bottle rupture take place. A number of ancillary advantages are conferred also by the coatings and these include: a. Coatings preserve the glass surface from weathering effects. b. Coatings provide ultra-violet protection if needed. c. They protect die glass surface from rough handling by die manufacturing plant and also die customer, which often acts to weaken the glass structure. d. They act to increase impact resistance. Impacting forces on die order of four to five times greater are required to shatter a plastic sheathed bottle. e. Special surface effects can be obtained. For instance: i. High gloss or low gloss, ii. Texturized or smoodi. iii. Transparent, translucent or opaque, iv. Essentially water white or colored. a. Single colors. b. Metallic colors. c. Variegated colors. d. Iridescent colors. e. Nacreous colors. (Pearlescent) f. They allow the safe utilization of pressures over about 20psigat 70°F, (138kPaat 21.1°C), as well as larger sizes up to 4 oz. (118.3 ml) nominal capacity for flammable compressed gases. g. They improve the filling aesthetics, especially for long, narrow-necked bottles, where piston fillers can cause a wide spread of fill levels. The use of translucent or opaque coatings obscures the men- iscal lines. h. They may improve product aesdietics. An essentially opaque coating can effectively hide traces of precipitated components of the essential oil. Also, such coatings eliminate the need to color the product by adding D&C and/or FD&C dyes to the concentrate. The limitations of plastic coated bottles include the increase in unit cost. Also, small surface designs on the glass, such as flutes, diamonds, designers initials, scrolls and so forth, are so filled in by the plastic that these enchancing effects are best eliminated from the botde design in the first place. Finally, a few people may object to the feel of the plastic surface as "non- cosmetic", when compared with the smooth, solid feel of glass. In order to apply the bonded type coatings now standard in the U.S.A. for plastic sheathed bottles, the pristine glassware is suspended from soft metal or plastic spring holders diat fit widiin die opening and
Glass Aerosols 115 spread out. The bottles are mildly preheated and are then run through a dip machine, where they are immersed almost completely in a warm bath of clear adhesive. The excess adhesive is then drained electrostatically off and the remaining film heated electrically to bring about a partial curing effect. In a similar fashion the bottles are passed through a fairly viscous bath of plastisol: a concentrated collodial dispersion of high molecular weight polyvinyl chloride in a liquid plasticizer blend. The fluid plastisol clings to the bottle as a gel structure which has little physical integrity. After the excess is drained off electrostatically it forms a layer about 0.5 mm in average thickness, conforming essentially to the geometry of the bottle. The unit then passes dirough a heating stage which fuses the solid resin, bonds it to the adhesive layer, and develops such properties as good tensile strength, tear resistance and impact absorbing properties. The coated unit now passes through a final dip machine containing a dispersion of high molecular weight polyvinyl chloride with a different molecular orientation. Upon curing, the top layer bonds to the "rigisol" lamination and forms a relatively soft covering that is still high in tensile strength and provides good impact absorbing properties. The bottles are then trimmed around the top of the neck and decorated to suit. Both the dipping and fusing cycles must be controlled carefully to produce coatings of optimum thickness and physical properties. The use of an excess of primary plasticizer, for instance, will produce a soft, tacky coating of low tensile strength. If a secondary plasticizer is used in the coating compound there is die possibility that it will weep out of the coating structure and solubilize lacquered or varnished furniture finishes. Back in the 1960s some plastic coated bottles left rings on vanity tops and dressing tables, but mis problem has long since been eliminated. Coating thicknesses on the order of 0.01" to 0.10 " (0.25 to 2.5 mm) are applied easily from bath dipping systems, but normally the coating on an aerosol bottle will run from 0.035" to 0.055" (0.9 to 1.4 mm), depending upon the size of the bottle and the surface area to be covered. On bottles of three ounces (90 ml) or larger, the average thickness of the surface coating works out to be about 1.4 times the square inch area equals the thickness in mils (0.00J "). This relationship applies to all types of coatings. There are two major coating systems in use at present. Both systems use polyvinyl chloride resins in a plastisol system as the film former. They differ only in the end product being manufactured. These coating systems are: a. Non-bonded, vented coatings. At one time this was the only coating for glass aerosols. It is still used widely in Europe. A bottle finish with a circular grove is required. When the bottle is broken, the plastic coating swells up like a small misshapen balloon, retaining the glass and allowing a controlled emission of the contents through venting holes pierced through the plastic sheath during the manufacturing process. It is not considered satisfactory for glass aerosols that use hydrocarbon propellents due to flammabililty considerations. b. Bonded coatings. There are two types: the simple plastisol and die laminated or Lamisol type. In each the bottle should have a conventional (non-grooved) finish, almough grooved ware can certainly be used. An adhesive primer is applied to the glass as described above, after which either one or two coatings of polyvinyl chloride are applied and cured in place. If such a bottle should break, the energies con- Figure 3. Coated Glass Cylinder Rounds by Wheaton Aerosols Company
116 The Aerosol Handbook tained within the package are not released immediately. The coating remains intact for an indefinite period of time, even though the bottle is obviously broken inside. No significant expansion takes place. This metastable condition continues to exist until plastic fatigue allows a small splinter of glass to penetrate the jacket. Then the energies will dissipate slowly through the tiny hole thus formed. The effect can be compared to the breaking of a piece of safety glass. Vent holes are useless for bonded systems and are never incorporated into such coatings. Glassware to be used with non-bonded coatings must be blow-molded with plastic key lock grooves under the lip. The coating must also be vented, either by means of pinpoint slits or with positive 0.090" (2.3 mm) diameter holes, to allow for the controlled released of the contents without stress rupture of the coating. This type of coating is no longer used in the U.S.A. because of concern over the flammability of released hydrocarbon/alcohol formulations. Decoration of Glass Containers Plain glass aerosol ware may be given an interesting variety of finishes. The Wheaton Aerosols Company provides three surface treatments'. a. Crystal Clear. An ultra-thin clear titania coating b. Moonsheen. A silvery transparent titania coating. c. Rainbow Iridescent. A coating providing a kaleidoscope of shimmering transparent color. Bottles may be silk-screened by conventional methods, just prior to the lubricating step. Two-color silk-screening is available also for special effects. Many interesting innovations are available for the decoration of plastic coated bottles. Pearlescent and other special colors may be used for unique effects. Colors may be sprayed directly onto the bottle, after which transparent or translucent coatings are applied. These include golds, silvers and bronzes, as well as shaded or blended two-color combinations. For the exotic taste, the plastic coating may be enhanced by the addition of a tiny jewel to embellish the label or silk- screened design. Bottles are available with bands of gold or silver filigree, a preformed metal ring or shoulder sleeve, or a metal or molded plastic foot or base. Silk-screening in one or two colors is recommended for a quality appearance and superior durability. During the custom filling operation, paper or foil labels can be applied to either unprinted or silk- screened bottles. Pressure Considerations The ideal glass aerosol, from a pressure resistance and strength standpoint, would be a very small sphere. The perfect sphere would also be the least expensive to produce. Being practical, however, it is necessary to design glass bottles into more distinctive, attractive and utilitarian shapes, with the design and sizes limited only by pressure resistance and strength considerations. Many variables enter into the design of such containers. Of prime importance is the utilization of shapes which permit good distribution of glass and elimination of strain through proper annealing. Whenever possible, sharp corners and large flat areas must be avoided. For optimum designs, all horizontal flat areas should have a minimum 30° taper, and all radii should be not less than 3/16" (4.8 mm). As bottle sizes increase, the use of plastic coatings becomes more imperative from a safety standpoint. Glass thickness and plastic thickness must be increased to maintain proper strength and protection against impaction. Plain glass aerosols are not normally made in sizes over two ounces, and the SAF Process bottles are not produced in models larger than three ounce capacity. Even here, certain cylindrical or other less sturdy designs are made available for use only in conjunction with metal or plastic cases for the final product. The largest size for plastic coated bottles is the ten ounce Boston Round design, although still larger sizes are currently being produced in Europe. Glass derives a great deal of its strength from an unblemished surface, and since the surface of glass aerosols is normally under some compression in relation to the underlying material, anything which disturbs the surface produces a region where tensional stresses accumulate. Glass is extremely strong in compression, but relatively weak in tension. Any bruises, abrasions, scratches or other impaction related surface aberrations will serve as stress concentraters for forces applied to the bottle, often reducing the strength of the bottles to less than half the original strength. Even the physio-chemical effects of fingermarks can be shown to reduce the strength of pristine glass surfaces. It is for these reasons that glass manufacturers handle glass with great delicacy and strive to protect and preserve the original surface properties by the use of special oxide films and lubrication techniques.
Glass Aerosols 117 Glass is actually such a strong material that the internal pressure of the aerosol contents has almost nothing to do with bringing about breakage. Bottles can often withstand pressures in excess of 1000 psig (6.89 MPa). Glass fragmentation is almost always impact related. However, in the case of defective bottles, such as those that have severe strains or cracks, the exertion of substantial pressure will cause bursting, and this has caused both the glass manufacturer and the filler to use pressure as a quality assurance tool. Some fillers undertake a 100% pneumatic pressure test on bottles just prior to the filling step, although this is not now recommended, since pressure retention properties may be reduced. Nitrogen or dry, filtered compressed air is used at pressures in the 120 - 150 psig (0.83 to 1.03 MPa) range. A heavy plastic or metal shroud covers the bottle at this stage to prevent possible injuries to personnel. In practice, defective bottles are effectively weeded out during hot-tanking. During the period ending about 1973 products in plain glass aerosols bottles were usually formulated to give pressures not over about 15 psig at 70°F (103 kPa at 21.1°C) under normal conditions where die amount of entrapped air was nil. This suggestion related to the use of anhydrous combinations of ethanol and P-114 (sym. dichlorotetrafluoroethane), where the viable air- free formulations exerted pressures in the 10 to 13 psig at 70°F (6.9 to 9.0 kPa at 21.1°C) range. During that period a few marketers added very modest amounts of n-butane, into the sealed bottle, backwards through the valve, in order to achieve the double economy of a low- cost propellent and an increasd volume of total product. This propellent could be added without disturbing the 15 psig (103 kPa) maximum, since the hydrocarbon exerts only a pressure of 16.7 psig at 70°F (115 kPa at 21.1 °C). In those days, depending upon the air content of the ethanol and propellent, the temperatures used for the refrigeration filling operation and other minor factors, a 1 to 3 psi (7 to 21 kPa) partial pressure of entrapped air might be included in the total pressure. It was much less common to add the propellent through the valve by a pressure loading technique. If this method was used, without removing air by purging with a con- densible gas, partial air pressures up as high as 21 psi (145 kPa) might result, leading to total pressures up to about 36 psig at 70°F (248 kPa at 21.1°C). This might appear like a dangerous way to go, but actually, virtually all the energy in the product is that developed by the liquefied propellent, so that these units were probably about 99% as safe as the essentially air-free counterparts. (The ballistic energy is admittedly higher for air-containing dispensers, but not total energy.) The use of chlorofluorocarbon propellents has persisted in Europe, Japan and other countries after 1974, but in the U.S.A. this year marked the beginning of a steep decline in the use of such gases for essentially all aerosol uses. By about 1977, there were very few chlorofluorocarbon type glass aerosols in the U.S.A. and substantial research programs were underway to develop suitable hydrocarbon-based formulas for this packaging form. By 1982, the use of hydrocarbon propellents had increased to cover 100% of U.S.A. glass aerosols (except certain medicinals) and a substantial percentage of those produced in Europe. Due to a regulation that prohibited the use of hydrocarbons for any cosmetic products, the glass aerosol industry in Japan was still 100% committed to the use of chlorofluorocarbon gases. The preferred hydrocarbon propellents consisted of Cosmetic Grade n-butane, Cosmetic Grade blends of n-butane and isobutane (such as C-24, 55w% isobutane and45w% n-butane), and Cosmetic Grade combinations of n-butane and propane (as C-41, 22w% propane and 78w% n-butane) all used in the range of 12 to 20% of the total product. The question of maximum pressure (and maximum energy) for glass aerosols continued, having been at least partly resolved (unsatisfactorily) in Europe by regulatory fiat. For uncoated glass bottles in Europe the pressure limit is 1.50 bar (21.75 psig or 150 kPa) at 20°C (68°F), provided the amount of liquefied gas is no more than 50w% of the total formula. If the propellent level exceeds 50w%, the pressure ceiling is reduced, although unsupportable by dynamic theories. According to standards of spray pattern and temperature performance now standard in Europe, this restriction has been considered a matter of concern. In the U.S.A. a general exemption from the D.O.T. (Department of Transportation) regulations applies to containers of not more than 4.00 fl. oz. (118.7 ml) in overflow capacity. Bottles larger than this may be shipped interstate provided the pressure does not exceed 40 psia at 70°F (276 kPa-absolute at 21.1°C) or, regardless of the pressure at 70°F (21.1°C), a pressure of 104 psia at 130°F (717 kPa-absolute at 54.4°C), or any flammable product having a pressure not to exceed 40 psia at 100°F (276 kPa-absolute at 37.8°C) as determined by ASTM Test D 323. The U.S.A. regulation
118 The Aerosol Handbook makes no distinction between uncoated and coated bottles. Since flammable aerosol products having the above 100°F (37.8°C) pressure in the ASTM D 323 Reid Tester can be expected to have a pressure of no more than about 1 psig at 70° (69 kPa at 21.1°C) it is apparent that this aspect of the regulation is an effective barrier to the interstate shipment of any hydrocarbon- type glass aerosol where the bottle has a capacity of over 4.00 fl. oz. (118.7 ml). At least two firms have applied to the D.O.T. for special exemptions to permit the export of relatively large coated bottles of various cologne products to the Arab countries and other destinations. Also in the U. S. A., the CSMA Aerosol Guide (page 42 of the Seventh Edition) recommends that uncoated glass aerosols not be pressurized to a level greater than 18 psig at 70°F (124 kPa at 21.1°C), including the partial pressure of occluded air. In the case of simple plastisol coated glass aerosols the recommended pressure maximum is about 25 psig at 70°F (172 kPa at 21.1°C) including air, and where a bonded type composite coating is used, such higher pressures as may be needed to achieve the desired spray or foam are approved. These are industry recommendations approved in 1976. They carry no regulatory authority. In rare instances carbon dioxide, nitrous oxide or nitrogen may be used as the propellent gas. In such cases the CSMA Aerosol Guide recommends a maximum pressure of 90 psig at 70°F (621 kPa at 21.1 °C), and the container should not be filled to over 70v% of capacity. The advice is based upon a recognition that only from about 0.3 to 5.2% of the total content weight will be made up of the dissolved propellent gas, depending upon the propellent selection and the solvent composition of the concentrate. This little propellent will keep the release energy sufficiently low in the event of a bursting incident. The bursting energy released by the terminal impaction of a given plain glass aerosol with 80% P-l 14 will be essentially the same as if the formulation contained only 40% P-l 14. Similarly, a glass aerosol containing 100 g of a 30% P-l 14 formula will explode with the same kinetic energy as one containing 50 g of a 60% P-l 14 composition. Although P-l 14 has almost exactly three times the molecular weight of n-butane (and they have about the same pressure) a composition containing 20% n-butane will have the same release energy as the same weight of a formula containing about 60% P-l 14. And finally, since pure P-l2 has about 5.5 times the pressure and 70% the molecular weight of P-l 14, a given glass aerosol with, say, 50% P-l2 should display about 7.6 times the energy of a 50% P-l 14 counterpart upon rupture. Bursting energy is concentrated in the vapor space, with volume and pressure being the dominant factors. These considerations actually relate to behavior in a vacuum at some fixed temperature in the ambient range, but can be applied to a room temperature atmospheric burst with reasonable accuracy. Edmund Budzilek, formerly the Technical Director of the Wheaton Aerosols Company and long regarded as the premier authority on glass aerosols, suggests that gas expansion values are isothermal, but ballistic energy is adiabatic, and can be derived from the work equation: Work(orB.E.) = PV' |"l ( ?*)"'*] in inch-pounds, at constant entropy. Pi is the pressure of the aerosol (psi-abs.), P2 is the atmospheric pressure (psi-abs.), Vi is the volume of the vapor space (cu. in.) and K is the ratio of specific heats (Cp/Cv). During the 1960s he derived a large group of product energy values for various propellents and their percentages in ethanol by equating the expansion volumes of the mol fraction of propellent with the rate of expansion, for any fixed product weight and head space volume to be referenced. The data are presented in Table I, where we have included equivalent values for some hydrocarbon propellents, thus making the data more relevant to the present (non-CFC) situation in the U.S.A. The table is not thermodynamically accurate, but will nevertheless serve as a good relative guide. Potential propellent energy translates to ballistic energy (work) upon terminal impaction of a plain glass aerosol, and this can be related to ballistic fragment spread, or ballistic hazard. As a consequence, the approximate numbers in Table I can be considered as a frangible container hazard index. An arbitrary value of 3.40 has been used to divide acceptable propellent compositions and levels from unacceptable ones in the case of a plain glass bottle of typical two-ounce (60 ml) nominal capacity. For bottles of one-ounce (30 ml) nominal capacity this divider would move upward, to about 6.80. The greater compositional latitude is compensated by the increased resistance of the smaller bottle to breakage, the statistically reduced size of the glass fragments and the reduction of propellent weight in keeping with the smaller volume of the container.
Glass Aerosols 119 For glass aerosols, particularly uncoated glass aerosols utilizing hydrocarbon propellents, there are two distinct hazards which must be taken into consideration when establishing a total hazard potential: ballistic fragment spread and flammability. According to Budzilek (priv. comm.) the most logical measure of relative flammability is the critical distance from the burst point, beyond which the released contents would not be expected to ignite. Although theoretically a hemisphere of flammable mist would be expected upon bursting, the vertical vector appears to be somewhat depressed by the momentarily overlying mass of the container, plus the density of the released material — compared to air. By discounting spurt or flare effects and considering only the average diameter of the flammable field (the area at or above the lower explosive limit) this dimension then becomes a direct function of the square root of the flammable content weight of the aerosol. The entire contents are used in the case of ethanol/hydrocarbon compositions. The exact percentage and composition of the hydrocarbon propellent, and the minor amount of water that may be present in some formulas, all seem to play only a minor role in controlling the relative diameter of the flammable field, at least within formula parameters now in common usage. Two general expressions can now be described. For non-flammable plain glass aerosols: Total Potential Hazard = Ballistic Energy = ki x w where ki is a constant, relating to the potential energy for various propellents and propellent percentages in a two fluid ounce (59 ml product volume) aerosol bottle, and where w is the content weight. On this basis the maximum, still acceptable Total Potential Hazard for a non-flammable aerosol with a typical formula density of 1.00 g/ml at 70°F (21°C) becomes: Total Potential Hazard = 3.40 x (59 x 1.00) = 200 Table I Relative Propellent Energy, As A Guide To Bottle Selection Propellent P-12 P-12/11 P-12/11 P-12/11 P-12/11 P-12/114 P-12/114 P-12/114 P-12/114 P-12/114 P-12/114 P-12/114 P-114 C-17* C-24" C-31"** C-41***' P-152a (100%) (50/50) (40/60) (35/65) (30/70) (40/60) (35/65) (30/70) (25/75) (20/80) (15/85) (10/90) (100%) (100%) (100%) (100%) 75 10.0 5.95 5.14 4.67 4.23 6.08 5.65 5.23 4.70 4.41 3.80 3.34 2.30 60 8.13 4.75 4.10 3.74 3.38 4.85 4.52 4.17 3.82 3.45 3.08 2.68 1.85 1 50 6.71 3.99 3.78 3.12 2.83 4.05 3.77 3.49 3.19 2.87 2.57 2.24 1.54 Per Cent Propellent By Weight 40 30 20 5.37 3.19 2.73 2.49 2.25 3.40 3.01 2.78 2.54 2.30 2.05 1.77 1.23 4.02 2.36 2.04 1.87 1.69 2.42 2.23 2.09 1.91 1.72 1.54 1.34 0.92 3.04 4.30 5.54 7.21 2.68 1.07 1.61 0.51 2.01 2.84 3.66 4.83 4.89 15 2.00 0.78 1.20 0.36 1.50 2.12 2.75 3.63 3.67 10 1.34 — — 0.49 0.08 0.75 0.69 0.63 0.57 0.50 0.29 0.20 0.98 1.38 1.79 2.35 2.30 isobutane and 45w% n-butane. 'Cosmetic Grade n-butane. "Cosmetic Grade blend of 55w*? * "Cosmetic Grade isobutane. "Cosmetic Grade blend of 78w% n-butane and 22w? i propane. Compositions to the right of the solid lines are generally considered acceptable for plain glass aerosol units up to a nominal two-ounce (59 ml) capacity, e.g. below 3.40.
120 The Aerosol Handbook For flammable plain glass aerosols having a typical density of 0.73 g/ml at 70°F (21.1°C): Total Potential Hazard = Ballistic Energy + Flammable Field Diameter = k2 (w + Vw~) No coefficient has been developed to modify the relative size of the two component hazards since the question of which is more dangerous: flying glass or fire, is subject to a thousand interpretations and is therefore moot. In this treatment the relationship is merely left at 1:1. Considering flammable products in plain glass aerosols, which are limited in bottle size to a nominal capacity of one fluid ounce (29.5 ml product volume) for hydrocarbon formulas by informal industry agreement, the value of the maximum still acceptable k factor can be derived to make it consistant with the above k2 figure of 200 for Total Potential Hazard, e.g. ki = 200 = k2 [(29.5 xO.73) + V29.5x0.73 ] k = 7.64 One of the most popular aerosol colognes on the market in 1982 comes in a totally silkscreened plain glass cylindrical bottle containing 0.26 ounces (7.37 g) of product. The propellent is C-41 at 20w% of the total contents. Solving for the Total Potential Hazard we get: Total Potential Hazard = k2 (7.37 + -JTM) = 77.0 which is much less than the arbitrary TPHmax of 200. On this basis the package may be considered safe, even though the Relative Propellent Energy is 4.83, as shown in Table I. The small product fill is quite important in this case. Had the bottle contained one ounce (28.4 g) of the product the TPH would have been 257.7 (unacceptably high). The low density would have made it necessary to use a bottle with a nominal capacity of at least 1.5 fl. oz. (44.3 ml), and this would have been a strong signal that a potentially dangerous combination existed, since the industry informal maximum of one fluid ounce (29.5 ml of product volume) would be exceeded. In developing this type data Budzilek (priv. comm.) prefers the expression: Total Potential Hazard : Ballistic Energy + Flammable Field Diameter = Ballistic Energy + Propellent Weight3'2 to provide a non-dimensional figure that appears to be a usable index. Using for an example a nominal two-ounce container, with an average volume of 67 to 71 ml and an occupied volume of 62 ml (maximum), we can consider both a CFC formula and a n.butane A-17 formula, with the latter containing 9.5 g of propellent. In the case of the non-flammable CFC propellent type, where the Flammable Field Diameter aspect is omitted from the equation, we have: Total Potential Hazard = (34.7)(0 •3) T / 14.7\109-1/1091* Ty-Knj) J +0 1.09 = 7.8 (non-dimensional) For the flammable n.butane A-17 propellent type, which also has 0.3 cu.in. vapor space in this example, we have: Total Potential Hazard = (34 t.7Xo.30)[- /^yn-v^y 1.11- 1 L V 34.7 /J = 7.6 + 29.3 = 36.9 (non-dimensional) Finally, if we compare the n.butane A-17 two-ounce package (above) to the same formula in a lA -ounce container, where the average volume is 22 to 24 ml and the occupied volume is 21 ml maximum, we have: Total Potential Hazard = (34.7)(0.061) 1.11 - 1 'Inch-pounds [.-(if) ""J-"". = 1.5 + 5.7 = 7.2 (non-dimensional)
Glass Aerosols 121 A possible weakness in the Budzilek approach is that the Total Potential Hazard appears to rise very fast as the aerosol bottle is emptied. Taking the last example, at a liquid volume of 95.5 % TPH = 7.2, but at a liquid volume of 0.1% (in other words, when the bottle is empty) TPH = 38.7. More work is clearly needed to better define these relationships. The Flammable Field Diameter has been determined in at least one series of tests, using pure A-17 (n-butane). Plain glass aerosol bottles were dropped 6 ft (1.83 m) onto a heavy steel plate. Three candles, each having a height of between 3 and 6 in (76 to 152 mm), were placed at various distances from the point of impaction. The candles were lit and bottles containing fixed amounts of A-17 were terminally impacted on the plate, releasing a cloud of propellent vapor. If the cloud did not ignite, the three candles were moved inward and the test repeated. If it did, they were moved outward. Finally, a diameter was reached where the three candles ignited about 50% of the time. The size of this circle is called the Flammable Field Diameter, or sometimes the Critical Radius. The resulting fireball has only about one-third this diameter or radius. The use of a "non-flammable" formulation in glass aerosols would seem to serve two main purposes: it would improve safety from a usage and rupture standpoint, and in the U.S.A. it would permit the sale of bottles with overflow capacities greater than 4 fluid ounces (118.3 ml). Such bottles are banned from interstate commerce by the D.O.T. if the contents are tested as "flammable". Two tests are employed. In the Flame Projection Test the contents are "not flammable" if, when sprayed from 6 " (152 mm) through the top third of a candle flame, a flame projection of less than 18 " (457 mm) is obtained at full valve opening, and also, a flashback to the dispenser is not obtained at any degree of valve opening. In the Closed Drum Test, the product is considered "not flammable" if it can be sprayed onto a 55 gallon (200 liter) drum for up to one minute without a large gout of flame being formed. The drum is closed, is laid on the side and has a candle burning at the center of the bottom. A search has been made for reasonable "not flammable" glass aerosol compositions and valve combinations, but with no real success. Some products pass the tests by default, such as foams, meterspray items and liquid steamers, but they are unimportant commercially, especially in the larger bottle sizes. Products with large amounts of chloro- fluorocarbon (CFC) propellents can easily be made "non-flammable", as defined. In the U.S.A., however, they are limited by law to certain essential pharmaceuticals. These are presented in bottles of relatively small capacity. The various hydrocarbon propellents give ' 'flammable'' results, even with near maximum levels of dissolved water in the formula. The compressed gases such as CO2 and N2O give coarse spray patterns of low interest. Finally we come to the only two gases that work: P-152a (1,1-difluoroethane) and DME (dimethylether), which pass the tests if large amounts of dissolved water are present in the formula. Although testing did not get underway until about 1980 due mainly to a supply problem, DME now looks like the preferred propellent. On a weight basis it is less than half as costly as P-152a. Reports have also circulated that it is preferred over both the CFCs and the hydrocarbon propellents for odorous fidelity. It gives Table II Ignition Consequences Upon Instant Release of C-17 (N-Butane) From A Ruptured Plain Glass Aerosol Weight Released (g) 0.1 0.5 1.0 2.0 3.0 4.0 5.0 6.0 10.0 Volume of Lower Explosive Concentration of Vapor (cu. ft.) (liters) 0.079 0.395 0.790 1.568 2.35 3.16 3.96 4.74 7.90 2.24 11.18 22.4 44.4 66.5 89.3 112.1 134.1 223.6 (ft.) 0.9 1.7 2.16 2.7 3.1 3.4 3.7 3.9 4.6 Critical Radius For Ignition (m) 0.27 0.52 0.66 0.82 0.94 1.04 1.13 1.19 1.40 (ft.) 0.3 0.57 0.72 0.91 1.05 1.15 1.24 1.31 1.56 Approximate Fireball Radius Upon Ignition (m) 0.09 0.17 0.22 0.28 0.32 0.35 0.33 0.40 0.48 Courtesy of Wheaton Aerosols Company
122 The Aerosol Handbook the truest performance odor compared to ethanolic standards. And lastly, DME forms a useful azeotrope with water (like its isomer, ethanol). This aids in the rapid evaporation of water from sprayed surfaces such as the skin. In turn, this allows the use of more water in some formulas, without inviting a sensation of excessive wetness. The properties of DME are described more fully in the propellent chapter, but it is sufficient to state here that it is capable of dissolving large amounts of water, thus making it quite unique as an aerosol propellent. In fact, if at least 7% of ethanol is present, any proportion of DME and water will form a single phase liquid system. Typical formulations have now been proposed for hydroalcoholic/DME colognes by Dr. Leonardus Bohnenn of Holland, a world renowned expert on DME technology (unpublished speech; 1981), and some are shown as follows: At least two of these formulas were are on the European market during 1981. The ability of a formula and valve combination to pass the Flame Projection Test and Closed Drum Test, and thus legally be called "not flammable", can be misleading in terms of drop test results. Dispensers containing P-152a and DME type "not flammable" products have been dropped and ruptured near open flames and the fireball effect was nearly as pronounced as for the equivalent hydrocarbon type formulas. This is not surprising if we consider the third formula of Table III, since the caloric content per unit of weight is about 73 % as high as it would be for the theoretical anhydrous ethanol counterpart, containing 25% hydrocarbon propellent. Table Glass Aerosol Bottle Designs Every glass aerosol bottle starts with a design concept. The idea is brought to the glass house, where skilled engineers and draftsmen create a final design that conforms to geometries proven historically to be highly impact resistant and pressure tolerant. The final shape must also permit good distribution of glass and allow for the virtual elimination of strain by proper annealing. Swirls, ribs, fluting or other surface features may be added, especially for uncoated bottles, since they appear to increase the resistance of the glass to accidental breakage. The capacity of the bottle must be considered in order to allow for an adequate outage space, so that the bottle will never become liquistatically filled under reasonable forseeable filling conditions. If this should occur, tremendous pressures will be generated in the dispenser. Most often the result is a lifting of the clinched valve ferrule, with gross leakage as a consequence. But in the case of bottles with flat wall surfaces, thin glass or other weakening features, rupture will probably occur first. Uncoated Glass Aerosol Designs Uncoated glass aerosol bottles are available from the three U.S.A. manufacturers, as well as Saint-Gobain Des Jonqueres, France and several other firms in Europe. The range of sizes extends from about 5 to 100 ml, but those in excess of 30 ml are strongly discouraged in the U.S.A. for flammable compositions under product stewardship programs exercised by the glass- makers. Both stock molds and private molds are III Various Aerosol Colognes, Based On Use of Dimethylether Ingredients Aluminum Can Container Type Aluminum Can Glass Bottle Glass Bottle* Essential Oil (Perfume) Ethanol (Andydrous Basis) De-ionized Water Inhibitor* * DME (Dimethylether) 2.5 25 22.3 0.2 50 2.5 45 17.3 0.2 35 2.5 55 17.5 25 5 70 15 10 Pressure (psig at 70°F) Pressure (kPa at 21.1 °C) Flame Projection Test*** 40 276 Non-F. 30 207 Non-F. 20 138 Non-F. 1 7 n/a. *Actually a toilet water with pump-spray valve, although a true aerosol. The DME is added as a fragrance intensifier and (in Europe) to reduce the amount of heavily taxed ethanol that is included. ••Quaternary ammonium phosphates or other effective systems. "••When tested with a suitable valve, (n/a = not applicable)
Glass Aerosols 123 available. Most of the stock items consist of straight wall "Cylinder Round" or "Boston Round" designs. Important design aspects are even glass distribution, prevention of concentrated stress areas, avoidance of sharp angles, and making sure there will be no rapid inflections in shape. Oblong shapes are difficult to execute. The thinnest wall section, or the point of greatest stress, should not coincide with the outer periphery of the bottle, since this surface is the one most likely to be bruised when bottles impact each other or some other hard surface during handling. For instance, the area where the side walls join the base (sometimes referred to as the Murgatroyd Belt) is normally an area of major stress concentration. If the lower side walls are tapered inward, so that there is less danger of the bottle being scratched in this area, then the chance of subsequent container failure is minimized. Most bottles have this design attribute, especially the larger sizes. To improve the safety and appearance of uncoated glass aerosols some manufacturers have developed special types of glass, as well as surface coatings that improve resistance to breakage, scratches and abrasion. For example, a thin film of metal oxide deposited on the outer surface of the container helps to protect it by making the surface substantially tougher than that of the original untreated glass. The Wheaton "SAF Process" uncoated bottles provide an example of one highly effective surface treatment of this type. A large listing of the Wheaton plain bottles is given in Table IV. Plain glass aerosol bottles offered by other suppliers are listed in Figure 4 and Figure 5. Plastic Coated Glass Aerosol Designs The simplest designs for plastic sheathed bottles are the cylinders. There are two main varieties: the "Cylinder Rounds" and the "Boston Rounds". Sometimes they are referred to as the "Aerosol Rounds". The Bostons are characterized by a more rounded top contour and the availability of larger sizes. Table IV Wheaton "SAF" Process Uncoated Aerosols and Plastic Coated Aerosols Mold No. S-775C S-633 S-329 S-111B S-12A S-7A S-791C S-275 S-2053F1 S-1744F1 S-2320FX S-1844F1 SS-1141F S-1409F1 S-2605F S-1744F1* S-1844F1 S-1527F1 S-3083F S-1743F1 S-2320F" S-204F6 S-1409F1 M-937F Exterior Finish Plain Plain Plain Plain Plain Plain Plain Plain Plain Plain Plain Plain Plain Plain Plain Coated Coated Coated Coated Coated Coated Coated Coated Coated Finish (mm) 13 13 13 13 13 13 13 13 15 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 Practical Fill (ml) 1.0 1.5 2.0 3.5 5.0 10.0 12.0 15.0 7.0 8.0 10.0 10.0 11.9 20.0 29.6 7.0 10.0 30. 59. 89. 10.0 15.0 20.0 118. Overflow Capacity (ml) 1.8 1.9 2.6 5.0 8.5 12.7 17.0 20.0 8.3 10.5 13.0 13.0 15.8 26.0 33.2 10.0 13.0 36. 68. 106. 12.0 23.0 26.0 128. Height (mm) 33 36 40 45 53 60 59 65 65 59 54 64 73 70 93 60 64 100 108 129 55 60 70 116 Diameter (mm) 15 14 15 18 19 23 26 27 17 21 24 21 19 30 32 22 23 31 37 43 25 33 32 52 All plain (uncoated) bottles are available only as rounds. *Bottles in this grouping are available as cylinder rounds. **Bottles in this grouping are available as Boston rounds. Next Page
Glass Aerosols Previous Page available. Most of the stock items consist of straight wall "Cylinder Round" or "Boston Round" designs. Important design aspects are even glass distribution, prevention of concentrated stress areas, avoidance of sharp angles, and making sure there will be no rapid inflections in shape. Oblong shapes are difficult to execute. The thinnest wall section, or the point of greatest stress, should not coincide with the outer periphery of the bottle, since this surface is the one most likely to be bruised when bottles impact each other or some other hard surface during handling. For instance, the area where the side walls join the base (sometimes referred to as the Murgatroyd Belt) is normally an area of major stress concentration. If the lower side walls are tapered inward, so that there is less danger of the bottle being scratched in this area, then the chance of subsequent container failure is minimized. Most bottles have this design attribute, especially the larger sizes. To improve the safety and appearance of uncoated glass aerosols some manufacturers have developed 123 special types of glass, as well as surface coatings that improve resistance to breakage, scratches and abrasion. For example, a thin film of metal oxide deposited on the outer surface of the container helps to protect it by making the surface substantially tougher than that of the original untreated glass. The Wheaton "SAF Process" uncoated bottles provide an example of one highly effective surface treatment of this type. A large listing of the Wheaton plain bottles is given in Table IV. Plain glass aerosol bottles offered by other suppliers are listed in Figure 4 and Figure 5. Plastic Coated Glass Aerosol Designs The simplest designs for plastic sheathed bottles are the cylinders. There are two main varieties: the "Cylinder Rounds" and the "Boston Rounds". Sometimes they are referred to as the "Aerosol Rounds". The Bostons are characterized by a more rounded top contour and the availability of larger sizes. Table IV Wheaton "SAF" Process Uncoated Aerosols and Plastic Coated Aerosols Mold No. S-775C S-633 S-329 S-111B S-12A S-7A S-791C S-275 S-2053F1 S-1744F1 S-2320FX S-1844F1 SS-1141F S-1409F1 S-2605F S-1744F1* S-1844F1 S-1527F1 S-3083F S-1743F1 S-2320F" S-204F6 S-1409F1 M-937F Exterior Finish Plain Plain Plain Plain Plain Plain Plain Plain Plain Plain Plain Plain Plain Plain Plain Coated Coated Coated Coated Coated Coated Coated Coated Coated Finish (mm) 13 13 13 13 13 13 13 13 15 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 Practical Fill (ml) 1.0 1.5 2.0 3.5 5.0 10.0 12.0 15.0 7.0 8.0 10.0 10.0 11.9 20.0 29.6 7.0 10.0 30. 59. 89. 10.0 15.0 20.0 118. Overflow Capacity (ml) 1.8 1.9 2.6 5.0 8.5 12.7 17.0 20.0 8.3 10.5 13.0 13.0 15.8 26.0 33.2 10.0 13.0 36. 68. 106. 12.0 23.0 26.0 128. Height (mm) 33 36 40 45 53 60 59 65 65 59 54 64 73 70 93 60 64 100 108 129 55 60 70 116 Diameter (mm) 15 14 15 18 19 23 26 27 17 21 24 21 19 30 32 22 23 31 37 43 25 33 32 52 All plain (uncoated) bottles are available only as rounds. *Bottles in this grouping are available as cylinder rounds. **Bottles in this grouping are available as Boston rounds.
124 The Aerosol Handbook In fact, Wheaton has made this design in the nominal 10 ounce size, with an overflow capacity of 12.0 fluid ounces (355 ml) and a diameter of nearly three inches (75 mm). A third major design is the "Ascot" bottle, with upward taper. These bottles look more stylish than the rounds. They are preferred for cosmetic uses while the round forms are almost selected for pharmaceutical products. The final category is the so-called "Fancy Aerosol" bottle, reserved for designs other than the rounds and ascots. They include ware with narrow waists, oval shapes, con vexed walls and footed bases. All the major fragrance houses purchase their own private molds from the glass manufacturer, sometimes as many as twenty at a time. The same bottle may be used for a specific line of fragrances, differentiated only by labeling and perhaps die basic coloration of the plastic coating. Figure 4. Glass Bottles by Risdon Corporation Item A 8 C 0 E F G Description' '.'*o*. Swirl, clear 2.3 oz. Swirl, clear 2.3 cz. Teardrop, clear 2.3 oz Cordial, clear 2.3 ox. Cordial, clear 2.3 02. Embark, clear 2.3 <«. Embark, clear Ht. {in.} 2.281 4.500 4.S10 4.640 ■3.281 i.em 4.281 Finish 20-FF-10S 20-FF-105 20-FF1O5 1-500-18 20-KK-105 1-400-18 20-FF-105 Dia (ii .890 1.640 1.550 1531 1.531 1.531 1.531 — I Wheaton Aerosols Company is die only present domestic source for plastic coated bottles, as mentioned earlier. However, at least two or three European firms also produce this packaging variety. (Many buyer's guides may be misleading here, since tiSey also list resellers.) Glass Aerosol Testing Procedures Glass, as an aerosol container, has enjoyed a history of at least 28 years tiSus far with a remarkably good safety record. Actually better than that of the beverage bottle; even better than that of metal aerosol containers. Pressure resistance is generally extremely high, sometimes exceeding 1000 psig (6.895 MPa). Glass containers, upon incineration, crack due to thermal shock long before product pressures build up to an intolerable level. Much of the safe history of glass is due to design sophistication and an unremitting program of quality control at the point of manufacture. Although there are only generalized, informal guidelines for some phases of the manufacture of glass aerosols, such as those set forth in three documents contained in the CSMA Aerosol Guide (Seventh Edition; 1981), there is a remarkable similarity between the testing programs of the various manufacturers, as well as in the internal design specifications for these containers. The design limitations are entirely self-imposed by the glass manufacturers. Conservative designs may be less intriguing in some instances, but will result in the production of ware which will pose a minimum of potential hazard to the ultimate consumer. Aerosol glass differs from non-pressurized glass primarily in that the designs are limited to those geometries which are most effective in enhancing pressure resistance and impact resistance. These are the only two characteristics that provide for consumer safety, and so the glass manufacturers attach more importance to tests aimed at the assurance of quality in these areas than to all other tests combined. An average quality assurance program will normally include the following procedures: a. Total Inspection (Visual) b. Statistical Inspection i. Internal pressure resistance. ii. Comprehensive load resistance, iii. Thermal shock resistance, iv. Wettability of the glass surface—
Glass Aerosols 125 v. Inspection for characteristics that would interfere widi coatings. c. Attribute Inspection i. Impact testing. ii. Glass distribution — by sectioning. iii. Drop testing. iv. Capacity determination. Total Visual Inspection This inspection is performed as bottles emerge from die annealing lehr at die glass plant. Anything appearing abnormal is culled out and returned to die melt as cullet. This includes bottles widi such defects as seeds, stones, marks, checks, odd shapes and so forth. When incoming ware is received at die coating facility, visual inspection is repeated, but diis time on a statistical basis. If such defects as cracks, chips or bruises have been picked up during handling in die glass plant, diey will usually be detected and die lot dien subjected to 100% inspection before coating or decorating operations takes place. Internal Pressure Testing This is a routine test applied periodically to samples from all mold cavities during any production run. It is used also at die coating plant, where incoming ware is inspected under Mil.Std.l05-D (Single Sampling), using an AQL of 0.65 for functional defects. Two procedures are used for pressure testing: a. Pneumatic Testing. The minimum pressure specification is checked by applying air pressure at 150 psig to die bottle for a dwell time of 17 seconds. b. Hydrostatic Testing. This is a considerably more sophisticated test, using a complex device capable Figure 5. Original Stock Design Aerosol Bottles by Carr-Lowrey Glass Company L33 '/SOI 5210 CATACITY MOULO MO Ii I&J1S OZ 3S99 A 1 3 OZ MM* Cvl ncttr I OZ 4sat »1B Foootl 4BM RIBBED AEROSOL BOTTLES \ ! I ft f b34B .. _ VSOZ' J/805E* w 20MM *¥aU A 4961 -A 13/4 02 30MM 485? -A 3 1 1OZ 10MM IS Fodtail Fluwd Fiund 1 1 I « CAFACtTV MOULD NO 7fjZ nti jo? on 1 DZ 4301 a oz 4304 > OZ 4303 2 OZ. 3*13 AEHOBOL MAOE WITH »HM CRIMT OH FINIEM
126 The Aerosol Handbook of imposing 29 progressively higher test pressures for a dwell time of three seconds on an automatic sequential basis. This device can test bottles to destruction, but the test is usually stopped at the 150 psig level. The pneumatic test is used with much greater frequency. At some plants it is applied on a 100% basis, using special equipment. Special precautions must be used to prevent flying glass problems, should bottles burst in the tester. Table V Drop Testing Results For Various Uncoated Glass Aerosols (100 Filled aerosol units per test.) Test No. Bottle Form Bottle Cap'y (ml) Content and Weight (g) Critical Dropping Heights* Him 1. Boston Round - SI. Mod.** 2. Boston Round - SI. Mod.** 3. Boston Round - SI. Mod. 4. Boston Round - SI. Mod. 5. Boston Round - Girdled 6. Boston Round - Girdled 7. Boston Round - Girdled 8. Boston Round - Girdled 9. Boston Round - SI. Mod. 10. Boston Round - SI. Mod. 11. Boston Round - SI. Mod. Slim 12. Boston Round - SI. Mod. Slim 13. Boston Round - Mod. Beaded** 14. Boston Round - Mod. Beaded** 15. Rounded Rectangular, with Ribs 16. Rounded Rectangular, with Ribs 17. Rounded Rectangular, with Ribs 18. Rounded Rectangular, with Ribs 19. Straignt-wall Oval (Rounded) 20. Straight-wall Oval (Rounded) 21. Straight-wall Oval (Octagon)* * 22. Straight-wall Oval (Octagon)** 23. Lightly Ribbed Round Tapered Downward 24. Lightly Ribbed Round Tapered Downward 25. Lightly Ribbed Round Tapered Downward 26. Lightly Ribbed Round Tapered Downward 27. Lightly Ribbed Round Tapered Downward 28. Lightly Ribbed Round Tapered Downward 29. Tapered Octagonal 30. Tapered Octagonal 63 63 110 110 57 57 112 112 35 35 55 55 33 33 54 54 104 104 35 35 43 43 61 61 120 120 90 90 60 60 Water Aerosol*** Water Aerosol Water Aerosol Water Aerosol Water Aerosol Water Aerosol Water Aerosol Water Aerosol Water Aerosol Water Aerosol Water Aerosol Water Aerosol Water Aerosol Water Aerosol Water Aerosol 55 55 94 94 50 50 95 95 32 32 48 48 30 30 50 50 88 88 31 31 35 35 52 52 97 97 74 74 54 54 3.00 4.00 3.00 3.00 3.00 2.50 3.00 3.00 3.00 3.00 3.00 2.50 1.50 1.50 2.50 2.50 2.50 2.00 3.50 3.50 0.50 1.00 2.00 2.00 2.50 2.50 2.50 2.50 3.00 3.50 4.90 5.01 4.23 4.29 4.53 4.43 4.26 4.21 4.59 4.69 4.23 4.23 3.11 3.23 4.33 4.41 4.10 4.01 4.62 4.80 1.84 2.42 3.82 3.43 4.22 4.42 4.09 4.39 4.77 4.74 5.50 5.50 5.50 5.50 5.50 5.50 5.00 5.00 5.50 5.50 5.00 5.00 4.00 4.50 5.50 5.50 5.00 5.00 5.50 5.50 4.00 4.00 5.00 5.00 5.50 5.50 5.50 5.50 5.50 5.50 *Ho is the dropping height maximum where no bottles will break. H50 is the dropping height which causes 50% breakage. Hioo is the dropping height minimum where all bottles will break. H50 is actually the arithmetric mean height, calculated from the data obtained by dropping 50 bottles sideways, then 50 bottles vertically The derivation is given in the CSMA Aerosol Guide pg. 48 (1981). All heights are shown in meters. To convert to feet, multiply by 3.28. **These bottle shapes are illustrated. Those in Test 1/2 were the most fracture resistant, those in Tests 21/22 were the least resistant, and those in Tests 13/14 were the next worst. ***The aerosol formulation used in these tests was: 16.5% Perfume, etc. 57.0% Ethanol - Anhydrous 26.5% Propellents 12/114(10:90) which had a density of about 1.0 at 68°F (20°C) and a pressure of 22 psig. (152 kPa) at this temperature. Actually, the nature of the contents had almost no effect upon the frangibility results.
Glass Aerosols 127 Drop Testing This is an important, highly controversial and publicized test, which has been written up as a standard test method in the CSMA Aerosol Guide (Seventh Edition; 1981). Put as succinctly as possible, filled plain or coated glass aerosol bottles are dropped from varying heights onto a heavy steel plate by the release of a vacuum-operated suction cup. Using 75 drops for each highly vulnerable position of the bottle under test, and centering in on the height at which about half the dropped bottles break, a record of drop data is generated which permits the statistical calculation of the arithmetic mean height at which 50% of the ware will fracture. Bottles are compared for drop resistance using this as a standard. It is also useful to determine the height below which no bottles will be expected to break. The consumer normally drops bottles through a distance from 40 to 70 inches (1.02 to 1.78 m). The higher figure applies mostly to bottles being taken down from a high storage shelf. Any bottles that shatter at test distances of less than about 6 feet (1.83 m) should be a matter of potential concern to the marketer. The data presented in Table V was developed by an aerosol bottle manufacturer in a southern European country. Details on the precise aspects of the dropping mechanism are not available, but the plain bottles were dropped upon a large, heavy steel plate. The method for calculating H5o (the arithmetic mean height, called Figure 6. Bottles Described in Table "X" in the CSMA Aerosol Guide), is comparable to that for deriving the value of "X". The profiles of the best, next-to-worst and worst of the thirty bottles tested are shown in Figure 6. Variations of the method in the CSMA Aerosol Guide may be used at the discretion of the glass maker or marketer. In one, 50 bottles are dropped 40" (1.02 m) onto the heel surface and a second group of 50 are dropped pre-oriented to land on the side and shoulder, from the same distance. The per cent of those which break is noted in each instance. Some laboratories prefer to drop unbroken bottles a second time, stating that their data matches results obtained where each bottle is dropped only once. If the formulation for the product to be packaged in the bottle is known it is best to use it in the testing program, at the target fill weight (U.S.A.), or volume (Europe, etc.). If nothing else, this precaution minimizes any possible critique of the methodology, which may be scrutinized in the case of undesirable test results or a product liability tort. The actual pressure of the formulation does not seem to be important, although there are a few people who suggest that internal pressure on the bottle tends to decrease the incidence of breakage, particularly in the case of relatively weak designs. One can theorize that the localized compressive force upon terminal impact is thousands of times greater than the counter-vector of product force against the impacted area. Glass breaks because the microflexing at any point, due to the V, in Relation to Breakage Resistance LEAST RESISTANT NEXT TO LEAST RESISTANT MOST RESISTANT
128 The Aerosol Handbook pressure of impact, causes the area immediately adjacent to go into tension. Glass is not very strong in tension, and it takes relatively little to exceed the flexural limit and cause failure. Any internal pressure which will resist such flexing will therefore aid non-breakage, at least within narrow limits which require statistical treatment to acquire validity. The kinetic force can be readily calculated by assuming a drop height of 40 inches (1.02 m). Over this short distance the effect of air friction on terminal velocity can be ignored safely. Thus, the bottle recovers essentially 100% of the energy required to raise it to the dropping height. This potential energy can be calculated from the formula: Potential Energy = mgh, where: m = mass (Newtons) (A force of about 9.8 kg of weight equals one Newton) g = acceleration due to gravity (9.76 m/s2) h. = height (meters) So that in the present situation: Potential Energy = m(9.76 m/s2)(1.02 m) 1 = (9.96 m2/s2) The formula for kinetic energy is: Kinetic Energy = ¥i (mv2) where: m = mass (Newtons) v = velocity (m/s) Since the kinetic energy at impact is essentially equivalent to the potential energy in the present example, it follows that: i/2 (mv2) = m (9.96m2/s2) v2 = 19.92 m2/s2 v =4.46 m/s at impact. Table VI provides terminal velocity figures for bottles dropped at a variety of heights. The table also shows the striking force (as a multiple of the weight of the dropped unit), and by using the example of a bottle and contents weighing 100 g we can calculate that the vertical force vector upon impaction will be 1900 g for a bottle dropped 40 inches (1.02 m). If we consider a typical impact area of 1.0 mm2, then the momentary compressive pressure exerted at that area upon striking will be 190 kg/cm2 (or 2,710 psi or 18.7 MPa). This is about a hundred times the magnitude of the content pressure, and explains why the pressure, or non-pressure of the content has essentially no effect upon bursting results. If the bottle is dropped onto a softer surface, such as a rubber or plastic tile floor, the area actually impacted can be expected to increase perhaps a hundredfold, compared with steel (as in the drop tester) or ceramic tile floors. The compressive pressure is then greatly reduced and the dispenser has a much better chance for survival. No attempt is generally made to assess the degree of hazard arising from flying glass shards. The tester is contained within a large cabinet, having a floor space of about four feet square (1.22 m square) so there is no op- Table VI Parameters Involved in Drop Testing Glass Aerosols Distances (ft) 0.063 0.125 0.250 0.500 0.750 1.000 2.000 3.333" 4.000 5.000 (m) 0.019 0.038 0.076 0.152 0.229 0.305 0.610 1.02 1.22 1.52 Terminal (ft/s) 2.0 2.9 4.0 5.6 6.9 8.0 11.5 14.7 16.0 17.0 Velocity (m/s) 0.61 0.88 1.22 1.71 2.10 2.4 3.5 4.5 4.9 5.2 Travel Time (») 0.063 0.090 0.125 0.175 0.215 0.25 0.36 0.47 0.50 0.53 Impact Momentum (Nm/S)' 0.0062 0.0090 0.0125 0.0175 0.0214 0.025 0.036 0.047 0.050 0.053 Striking Force (x weight) 0.8 1.5 2.4 4.0 6.0 7.5 13 19 22 26 "Momentum = Mass (Newtons) x Velocity (m/s) The mass is taken as that of a typical 100 g unit; e.g. about 0.0102 N 'Equal to 40 inches, the minimum dropping distance.
Glass Aerosols 129 portunity to determine the lateral or vertical spread of the fragments. There is little difference in lateral spread between bottles filled with water and those filled with pressurized products at TPH values of 200 or less. The energy of the propellent is less than the kinetic forces developed during the drop. There is, however, a significant difference in the height to which the fragments will rise upon breakage. A non-pressurized bottle will seldom have fragments which rise more than about six inches (150 mm) when it shatters, whereas a properly formulated aerosol will show a fragment height of up to about 20 inches (508 mm) upon breakage at room temperatures. At higher pressures the propellent becomes a greater determinant in developing the lateral spread. The size, contour and initial attitude of the glass fragments at the instant of impact will determine how far each will travel. A fairly small piece, cupped toward the explosive epicenter, and with its major axis of about 45°, may be expected to fly outward to the greatest extent. Many experts feel the drop test is seriously overrated. However, the apparent relationship to consumer mishaps has so much appeal to non-technical people that it will probably be around for some time to come. The concern, not only of injuries due to breakage, but of flammable consequences as well, has now gotten the U.S.A. marketers to adopt overwhelmingly the glass- maker's recommendations regarding pressures and the idea that bottles over one fluid ounce (nominal) (30 ml - nominal) should be plastic coated. This stance has acted to reduce consumer problems to the extent that no publicized lawsuits are known during 1979, 1980 and 1981, with only one in 1978 and three in 1977. In the case of plastic coated bottles, the drop test helps to evaluate the protective properties of the coating. The test will provide empirical data on the composite of: a. Bottle design. b. Coating thickness. c. Degree of Plastisol fusion and adhesion. d. Impact absorption. e. Fracture patterns. f. Hydrodynamics. g. Performance of venting systems - non U.S.A. h. Performance of bonding systems; e.g. rate of propellent release. All these parameters are so interrelated that it is usually extremely difficult, even for the expert, to determine the specific causes of failure in coated bottles without also resorting to extensive testing by methods other than the drop test. An exception is where some aspect is grossly out of line and can thus be pinpointed as the principal cause of failure. Many laboratories prefer to develop results that relate to the most severe, reasonably expected consumer drop circumstance, for example, a drop onto a steel plate from a distance of six feet (1.83 m) with the dispenser at 100° to 105°F (37.8° to 40.6°C). The steel plate simulates a ceramic tile floor. For plastic coated ware, temperature is important in two ways: the heat acts to elevate internal pressure, and it also renders the plastic softer and thus statistically more apt to develop pressure and glass containment problems. Comprehensive Load Testing In this test the bottle is subjected to a vertical load of about 500 to 1000 pounds. A certain percentage of the bottles are tested to destruction. The test is applied on a routine basis to samples from every mold cavity, often using the minimum acceptance level of 500 pounds of force. When bottles are subjected to incoming inspection at the decorating and coating plant, they are tested using the Mil.Std. 105D (Single Sampling) with 0.65% acceptance level for critical defects. Thermal Shock Testing Glass manufacturers apply this test principally to insure that their ware will stand up under routine 100 % hot-tanking, which is done by most aerosol fillers as part of their production process. Thermal shock testing is a routine quality assurance procedure, using a minimum temperature differential of 90°F. from cold to hot. During the development stage of a new container, thermal shocks are undertaken at much higher temperature ranges, in order to determine the mean failure level. But this destructive testing is not performed routinely. Impact Testing This is an attribute test, performed on a spot check or sporadic basis due to its time consuming nature. It is used principally to check new container designs during bottle development. Routine production ware are subjected to impact testing perhaps once per shift, to fill out the job history.
130 The Aerosol Handbook The impact tester itself is a weighted pendulum device, available from the American Glass Research Institute, and it is calibrated in terms of velocity (ips = inches per second, or mps = millimeters per second) rather than force units. The procedure supplied by the manufacturer is generally the one used. It is generally reproducible between laboratories. However, the evaluation of data resulting from impact tests should only be done in conjunction with that of other test work, and related to observations made during the particular run from which the test samples were collected. A typical specification for aerosol glass is 35 ips (889 mmps) minimum. Characteristics Interfering with Coatings Bottles are inspected routinely for such things as dropped bottoms, choked necks, excessive pushup and other factors which would interfere with, or detract from, the quality of the unit in its final coated form. Glass Distribution Testing During every production period, samples are collected from individual molds and are cut into four vertical sections with a silicon carbide saw or diamond studded cutting wheel. The sections are then studied to determine glass distribution. Minimum glass thickness must be retained at several critical areas, such as small radii loci. If the wall thickness falls below a minimum value at these critical points the mold is removed and all ware produced subsequent to the last acceptable test acceptable test is rejected. Minimum wall thickness will vary according to bottle shape and size, and whether it is to be plastic coated or not. Figures for any specific bottle are developed experimentally. Bottle weight provides an interim checking method for thickness, assuming distribution is within reasonable limits. Capacity Testing Prior to coating, glass bottles are inspected statistically for capacity and glass weight. Small variations below minimum glass weight are usually not serous, provided drop testing survival is still acceptable. However, significant increases in glass weight may suggest a short capacity situation. Capacity is an important consideration. Bottles are normally engineered to give headspaces up to 15% or so over nominal volume capacity designations. In fact, with coated ware, the 15% figure is often a minimum. This is particularly desirable for bottles that are going to be given opaque or translucent/opaque coatings, or opaque silk screening treatments, since these can act to obscure the product fill line during production. Marketers of uncoated bottles and transparent plastic coated ware are becoming increasingly interested in fill line aesthetics. The consumer appears to prefer aerosol bottles filled nearly to the brim, as is often the case with non-pressurized glass containers. As a result, glassmakers are being asked to provide ware with increasingly smaller outage space, and thus higher fill lines, in order to create the illusion of full measure. Other marketers act to cover the meniscal area with decoration of opaque plastic coatings. The label content declaration: net weight in ounces of deliverable product in the U.S.A. and net contents in ml in Europe and Japan, for instance, is not an important consideration to the consumer, compared with the visible evidence of fill line. Volume percentage fill thus becomes a very important consideration for certain bottle types. Where the customer does not regulate overflow capacity, as in stock bottle designs, the glass manufacturer often will size his container to provide a mean of about 12% outage space over the fluid ounce nominal fill volume. In practice this suggests a range of about 9 to 14% during any production run. If the custom bottle customer desires a tighter specification, then certain data should be supplied to the glassmaker; e.g. a. Stated label weight (g) =A b. Specific gravity of formulation, at a specified = B temperature. c. Expected maximum overfill factor (g) =C d. Valve displacement within bottle (ml) =D e. Minimum acceptable outage space, at the = E specified temperature. From these parameters the glassmaker can then calculate the overflow capacity of the "min bottle", e.g. the smallest capacity bottle to be produced during his production run, as: A +C +D B 1 nn _ Overflow Capacity <nA p x 1UU _ of "Min Bottle". 100 - E The custom glass can then be produced to a capacity specification so that the range will bottom out on the calculated overflow capacity of the "min bottle".
Glass Aerosols 131 In the U.S.A. the Department of Transportation requires only that the aerosol container not become liquid-filled when the contents are heated to 130°F (54.4°C). Outside the U.S.A. it is usually permissible to fill glass aerosols to a volume of up to 95.0% of capacity, measured at 50°C (122°F). During 1981 an aerosol industry recommendation was published (CSMA Aerosol Guide, Seventh Edition; 1981) that transparent or translucent bottles, with or without an essentially transparent plastic covering, may be filled to a maximum of 95.5v% at 130°F(54.4°C), provided the fill level is checked visually during production to assure compliance. Otherwise, the recommendation is for a 92.5v% maximum fill, measured at 130°F (54.4°C). Despite the recommendations, some bottles have been filled to about 96v% at 70°F (21.2°C), purely as a result of aesthetic considerations. The incidence of liquistatic distortion (of the valve seal) or glass breakage in the field has been extremely rare. Many potential problems are fully resolved by 100% inspection of filled ware during production, with overfilled units simply being sprayed down to reasonable fill lines. In the case of some seemingly opaque bottles, the fill line can be dimly seen using a sort of egg candling technique, where an intensely bright narrow slit of light is positioned on the far side of the bottle and the inspector looks through the bottle at this beam of illumination. Fatigue factors are an important consideration in this control step, and a shutter control assuring "no bottle, no light" is a very useful adjunct in minimizing this problem. It is a popular misconception that overfilled glass aerosols will be detected during hot-tanking. But in many cases hot tanks are not heated to more than about 110°F (43.3°C) and used more for leak detection and flushing than for anything else. Certain delicate perfume oils have been known to degrade at 135°F (57.2°C) for instance, and this is another consideration. Also, glass and plastic coated glass in particular are rather poor heat conductors, so that merely immersing the dispenser in, say, 135°F (57.2°C) water for a minute or two will not bring the contents up to anywhere near this temperature. Filling Glass Aerosols Special production lines are required for the filling of plain and coated glass aerosol bottles. In general they can also be used for filling smaller aluminum tubes and pure plastic bottles as well. This had led to the term "Tube and Bottle Line", or "20 mm Line". In many countries, production of glass aerosols is done in a rather primitive fashion, using "laboratory- sized' ' equipment capable of producing from 100 to 350 units per hour. In some of them the concentrate is chilled in dry ice and added to the bottle while it is sitting on a balance pan. Cooled propellent is then added from a glass beaker and the unit sealed as quickly thereafter as possible. If hot-tanking is done, it is by the immersion of a wire basketfull of ware into warm or hot water for a few minutes. Many orders in the 1000 to 10,000 unit range can be handled rather effectively in this manner. At one time during the 1970s the largest filler in Mexico had several "lines" of this type. Next larger in size is the manually-operated line, with a capacity of from about 400 to 8000 containers per eight-hour shift. The components are usually table- mounted and air-power is used for both operations and controls. The main sequence involves a piston-operated filler, bottle crimper, piston-operated propellent charger and then the hot tank. Units are moved between stations by hand, so there is no need for pucks, conveyors or other refinements. The larger glass aerosol lines are the straight line, single row, single indexing (speeds to 35 bpm) and inline, single row, double indexing (speeds to 70 or 75 bpm) modes. There are also some rotary machines which incorporate filling, crimping and gassing within one revolution of the containers. Compounding the Concentrate (Colognes and Perfumes) Many marketers prefer the use of relatively small SS-316 compounding tanks, ranging in the 200 to 500 gallon (760 to 1900 liter) area and having tight-fitting Propellant charger Crimper Basket-type test bath Figure 7. Manual Glass Aerosol Production Line Stations key to the line are shown. The filler, crimper and gasser are air operated and air regulated. Production is up to 1000 units per hour.
132 The Aerosol Handbook covers. Type SS-304 is often satisfactory, but a contract filler putting in new equipment should install the SS-316 in order to handle all requirements. Relatively slow, top-entering agitation is also needed. Most batches contain ethanol, water, perfume and possibly some colorants and extenders such as polyglycols or Purcellin Oil. The water is sometimes incorporated by using 190° ethanol, where it is a 5.00v% (7.22wt%) component of this essentially azeotropic commercial mixture. Although water was almost never included in the old P-12/P-114 colognes of the 1970s, it is now added with some frequency. The incorporation of water conveys both benefits and possible problems; for example: a. Advantages: i. Water usually imparts a green, lifting and fresh note to the fragrance. ii. Water reduces formulation cost by up to about S2.50/M one-ounce (30 ml) bottles, used at the 20% level. iii. It reduces flammability, at least statistically. iv. It is more difficult to break up into particles than ethanol, thus requires more propellent. Since hydrocarbon gases are less costly than ethanol this has advantageous aspects. b. Disadvantages: i. Water may force certain essential oil fonds, resins and other substantives out of solution and this may alter the fragrance balance. It may also reduce lasting time. ii. Water over 9% may limit the perfume oil level to about 8% or less, due to general incompatibility, leading to precipitation. Water is limited to 5 to 7 % when perfume oils increase to 12% of the concentrate. iii. It limits the ability of ethanol to function as a pressure suppressent, thus higher dispenser pressures may occur. iv. By increasing density slightly, more essential oil and other expensive items may be needed for a unit having a fixed volume of product. The concentrate batch is compounded at room temperature, with the water and then the colorants being the last ingredients to be added. After quality assurance approval, the batch is allowed to maturate; that is, to sit for one, three or seven days at room temperature in order to develop a fine precipitate of the incompatible elements of the essential oil. As a rule, increasing the level of essential oil acts to increase the time of maturation. After the aging step the batch is chilled and then filtered down to 10 m/i or less. It is then ready to be filled into bottles. Filling, Air Removal and Crimping (Colognes and Perfumes) Air removal is an important step, inasmuch as air causes a significant elevation in the pressure of the completed product. In rare instances it may also react with delicate perfumes, perhaps causing aldehydes to change to the corresponding carboxylic acids, and so forth. As a rule, as much air is removed as possible. In the pressure testing step, either air, nitrogen or carbon dioxide may be used to pressurize the bottle to as high as 150 psig (1.035 MPa), but carbon dioxide has the advantage of being a reasonably soluble compressed gas, and thus any residual traces in the bottle will not act to elevate the pressure to any measurable degree. By testing using carbon dioxide, only about 9% of the original air will remain in the bottle when the pressurizing head releases and the excess gases rush out. But even this small amount can be reduced. A few fillers use very warm bottles containing about 1 ml of ethanol, and subject these to the pressure test. The carbon dioxide carbon forms about a 7.5% solution in the ethanol and then, when the pressure is released the ethanol solution atomizes, so that the additional carbon dioxide and ethanol vapors can displace even more of the initial air content. A final sophistication is to pre-purge some of the air from the bottle using carbon dioxide, just prior to the pressure testing step. By using the combination of these three modes, an estimated 96 + % of the air can be removed. Such bottles should be filled with the concentrate as quickly as possible and then sealed, in order to minimize reentry of air through the open top of the container. In 1980 one of the more popular cologne sprays in the U.S.A. had the formulation: 12% Essential Oil 68% S.D. Alcohol 39c (190 proof) 92.78% Ethanol (and n-butyl phthalate denaturant) 7.22% Water 20.00% Propellent C-41 25.00% Propane 75.00% n. Butane
Glass Aerosols 133 It was revised during the following year by replacing the S.D. Alcohol 39c (190 proof) with S.D. Alcohol 40 (200 proof) and making other minor alterations. If we assume the target fill to be 0.23 oz. (6.52 g) of concentrate having a density of 0.811 g/ml at 70°F (21.1°C), then one gallon (3.79 liters) of concentrate will produce about 471 bottles, discounting manufacturing losses. From this it follows that a 55 gallon (200 liter) drum of finished concentrate would provide sufficient material for 25,900 bottles, or a day's production on a highspeed bottle line. As a corollary, the drum of concentrate might well have a valuation exceeding $2,000, largely dependent upon the cost of the essential oil. The finished concentrate is added to the bottle using a Filamatic or other high-accuracy piston filler with metal parts of SS-316 and elastomers preferably of Teflon. Where rubber' 'O' '-rings or other rubber parts must be used, either Buna-N or Buna-P are usually better than Neoprenes. The filled, purged bottle is then fitted with an appropriate valve by hand, after which the valve is crimped onto the neck to create a hermatic seal. The latter operation, also called clinching in the U.S.A. and swaging in the U.K., is commonly performed using a rather large collet with from 16 to 24 tines, joined to a solid hub. The collet is brought down over the aluminum or steel valve ferrule and the tines are then projected inward by means of a down-sliding plunger or mandrel sleeve. The ferrule wall is deformed inward, somewhat like the cap of a beverage bottle. This draws the outer sealing gasket down hard on the bottle finish and effects the seal. In is necessary to exert at least some flat compression on the valve sealing gasket. This is the primary sealing area for both plain and coated bottles. For plain bottles the crimping height specification can be given as: C.H. = + 0.40b + c + 2.00d ± 0.15b where: a = thickness of bottle lip—excluding sealing bead. b = thickness of valve sealing gasket. c = thickness of valve body flange—excluding sealing bead. d = thickness of valve ferrule. The mean, bottle should be used for determination of the "a" dimension. The other dimensions relate to the valve and are sufficiently reproducible so they need to be determined only once for any valve model. By using this equation to determine the height from the lowest extent of the skirt to the outer flat portion, flat compression on the valve sealing gasket will vary from about 22% for the maximum bottle to about 4% on the minimum bottle. The actual figures will be somewhat different for every lot of bottles. It should be noted that the sealing beads cut into the valve sealing gasket about 30% each way, so that the effective compression will be 60%, even if the "flat compression" is 0%. In practice the 60% figure must be regarded as a rough average, since there should always be some flat compression to enlarge it and some bead deterioration or imperfections (especially in the glass bead) to detract from it. For plastic coated bottles the formula becomes: C.H. = a + 0.40b + c + 2.00d + 0.015" ± 0.15b, where the dimensions are the same as before, except that the figure of 0.015 " must be added to compensate for the nominal amount of plastic expected to be present under the lip of the bottle finish. The figures for flat compression and effective compression of the valve sealing gasket remain as before, provided the nominal 0.015" vertical vector remains essentially constant. The experimental value for the crimp height on plastic bottles is a little more difficult to determine, since the ferrule skirt continues downward, past the crimp, necked in snugly against the container wall. It is most readily obtained by direct caliper measurements, as the vertical distance from the "hang up" line at the top of the crimped skirt area, where the contour changes rapidly, to the flat outermost ring at the top of the ferrule. a. 13 mm. valves: CD. = 0.757 + 0.005" (Reduction of 0.030" in diameter.) b. 15 mm. valves: CD. = 0.752 ± 0.006" (Reduction of 0.035" in diameter.) c. 20 mm. valves: CD. = 0.720 ± 0.008" (Reduction of 0.067 " in diameter.) However, because of the variation in coating thickness and bottle neck diameter it would be wise to determine the optimum crimp diameter for each lot of ware. When the crimp height is larger than usual, compression on the valve sealing gasket is reduced or eliminated to the point where sealing integrity is lost. Leakage will then take place in the case of uncoated bottles. However, for plastic coated bottles a secondary
134 The Aerosol Handbook seal exists where the crimp tightens the ferrule against the Plastisol sheath. This is not an effective way to seal, and the condition will usually result in latent leakers; that is, containers which leak only after several weeks or months of storage. If the crimp height is smaller than usual, the aluminum ferrule will be crushed hard against the glass, often becoming thinned or fractured. The anodized surface may be rubbed through. For plastic coated ware the plastic may cold flow downward and puff out the extreme bottom of the ferrule skirt. Sometimes it will "bubble" out, just below the skirt. In the event the crimp diameter is too shallow, the unit may leak as a consequence of insufficient compression at the valve sealing gasket. Sometimes leakage may commence only at higher pressures and temperatures. This is especially true for plastic coated units, where the plastic softens considerably with increasing temperature, allowing upward movement of the ferrule. With a proper diameter, pressures of over 400 psig (2.76 MPa) are required to unseat a 20 mm valve from a plastic coated bottle. If the crimp diameter is too deep, the collet tines may actually strike and even score the glass, in the case of plain bottles. For plastic coated ware, metal abrasions on the ferrule may be noted and plastic may be oozed out, forming a ring-like protuberance just below the skirt. In severe cases actual cutting of the plastic may occur, jeopardizing the safety of the bottle during its service life. Gassing Where chlorofluorocarbon propellents are used the filler has the option of adding them to the open bottle, on top of the chilled concentrate, or with the chilled concentrate. In fact, since these propellents often contributed to the slow precipitation of essential oil components, it was considered preferable to maturate the entire aerosol formulation in a tank chilled to about 20°F (-6.7°C) for about three days or so. Very little propellent loss was encounteed if the tank lid was taped tightly or otherwise sealed to the main section. This procedure is impractical with hydrocarbon propellents, due to their extreme flammability. They must be gassed into the bottle, backward through the opened valve, at pressures in the 400 to 850 psig (2.76 to 5.86 MPa) range, to insure a fast flow. Many glass bottle valves have a stem orifice of only 0.013" (33^m) and the specified weight of propellent must be forced past this restriction and into the bottle in one to two seconds. An accurate, small-scale piston filler is required. A number of suppliers have such equipment available. Hot Tanking In the U.S.A., the Department of Transportation requirements do not actually specify hot tanking for glass and coated glass aerosols. Nevertheless, hot tanking is still an excellent means of detecting leakers and cleaning the exterior surfaces of the dispenser, so this important production step should not be omitted. As a rule, warming the contents to about 100°F (37.8°C) will suffice to detect leakers and will still allow fairly rapid evaporation of residual moisture for the container after it passes through the air jet driers at the end of the hot tank unit. Both glass and (particularly) plastic coated glass are poor heat conductors, so, if a contents temperature of 100°F (37.8°) is desired the best way to get it is to pass ambient units through the hot tank several times, with the water set at progressively increasing temperatures, until the pressure of the unshaken units becomes equal to the equilibrium pressure of those contents at 100°F (37.8°C). The hot tank water temperature may have to be set much higher than this in order to attain the 100°F (37.8°C) heat condition. For a given bottle, content and hot tank, this determination need be made only once. Water temperatures in excess of 115°F (46.1°C) will normally be required to heat plain glass to the 100°F (37.8°C) level. Much higher hot tank temperatures will be needed in the case of plastic coated bottles. However, the tank water should never be set at temperatures over 135°F (57.2°C) if the article is immersed for over 3.5 minutes, or 140°F (60°C) for 1.5 minutes. Such heating is very hard on both the chemical and structural stability of Plastisol coatings. At these temperatures the plastic offers relatively little protection, should the unit break. It is preferable to have the hot tank conveyor belt run independently of any other drives. Then, should a breakdown take place elsewhere on the line, the hot tank can be kept going until the bottles are deposited out of the water, at the far end. It is also recognized that lengthy exposures to temperatures in the 140°F (60°C) area can have debilitating effects upon the stability of delicate perfumes and certain pharmaceutical ingredients. Thermal shock is sometimes a factor in hot tanking operations. Plastic coated bottles do not pose a prob-
Glass Aerosols 135 lem, since the warming rate of the glass is buffered. But where plain bottles, especially larger ones, are refrigeration filled and then hot tanked, substantial strains may be generated and some units may burst. A' 'waterfall" intermediate step is sometimes used, where room temperature water is poured over the bottle briefly, just before hot tanking. Because of thermal shock, increased pressures, decreased resistance of the plastic coatings and other factors, the hot tank should be well screened on top and the operator should wear protective clothing and a face mask. By the use of de-ionized recycle water, or tap water modified by the addition of about 0.2% Calgon (sodium hexametaphosphate) the emerging bottles can be dried by air blasts and normal evaporation without leaving water spots. Sometimes a small amount of detergent is added to hot tank water to promote cleaning. Many glass lines are not set up to provide sufficient time for the bottles to air dry. This means that the ware must be hand dried with cloths. The bottles are still quite warm at this point, so it is desirable to place rubber runner mats on the floor, and rubber mats on the table itself. This also holds true for the packing table area, where the bottles are put into display cartons, shadowpacks and final corrugate outer shippers. Labeling Most glass and plastic coated glass bottles are silk screened at the glass works. Others may be decorated by hot stamping, color-dec heat transfer labeling (to six colors), U-V offset and multi-color Tampo, by such firms as AndBro, Inc. of Pitman, NJ. Paper labeling plastic coated bottles has always been somewhat of a problem. Acrylic based adhesives have become available, and these are the type that work best with a polyvinyl chloride coating. Normal label adhesives are usually made with vinyl compounds which will extract the plasticizer from the coating, become soft and lose adhesion. Acrylics, on the other hand, block the plasticizer extraction and allow the initial adhesion to remain undisturbed. The Avery Label Company can supply paper and foil paper-backed labels utilizing their P-8 acrylic based adhesives, and other firms are also entering this area. A variety of automatic and semi-automatic labelers may be used for labeling glass aerosols. In some cases both silk-screening and spot labeling may be employed on the same bottle. An advantage of labeling over silk screening is that the manufacturing code may be affixed to the individual unit. This is of special importance for aeroceutical containers. Difficult label jobs are quite often done by hand, such as where precise location of a small, irregular label is required. The labels, backed with pressure-sensitive adhesive, are machine fed to the operator. Application speeds range from about 12 to 20 per minute, per person. Bottles having strong double curvatures cannot be labeled unless the labels are small, or are applied to the bottom of the unit. In many instances the bottle is left undecorated, with the product name applied to a gold lacquered collar and the "legal information" (manufacturer, address, code, net weight, and so forth) placed on a foil circle label attached to the base. Plain sand-blasted bottles are often labeled in this fashion. Composite containers are often used for cosmetic applications. Perhaps the simplest is where the plain glass bottle is press-fitted into a gold anodized filigree sheath. In others, a plain bottle is inserted into an aluminum tube, where it rests upon a shock absorbent foam pad at the bottom and is fitted with a 1% " or 1 Vi " diameter collar at the top, connecting it to the tube at this point. The collar is shouldered to accommodate the cover. Metal Fabrications, Inc. markets complete units of this type, where the valve is already crimped to the bottle, requiring only pressure loading and labeling. Figure 8. Clear Glass Bottle Prior to Foil Labeling A 3.5 oz clear glass bottle of cologne, prior to foil labeling. Uncoated glass units over 1.0 oz are uncommon in the U.S.A., due to the possibility of fracture and the dual hazards of flying glass and flam- mability of the hydrocarbon propellent formulation. L J ' JJ u
136 The Aerosol Handbook Marketing Summary The marketer interested in glass aerosols has the option of producing his own products or having them made by a contract filler. Considering a full-scale line as one capable of doing about 60 to 80 units per minute, there are now eight such lines along the east coast, two in the midwest (Indiana) and the equivalent of 1.5 in the west (California). In 1981 the average filling charge was about $180/M units. Several of the largest cologne and pharmaceutical marketers have preferred to do their filling in-house. For these firms seasonality may be a problem, since (depending upon product) from 30 to 65% of colognes and perfumes are sold during the pre-Christmas period. Some of the interest in aerosol colognes has been generated from the fact that women are now spending more on fragrance products than at any time in the past. Also, the aerosol is demonstrably better than the pump spray in terms of fragrance retention and shelf life, at least in most instances. And finally, use up is faster, causing an increase in sales volume. The pump- spray units can be expected to retain their predominance in the case of larger, more intricate bottle shapes, but aerosols should gain market share in the years to come.
137 PLASTIC AEROSOL CONTAINERS 4 Over the past twenty years or so quite a large number of plastics have been examined for use in the manufacture of aerosol containers. Polystyrenes, phenolic resins, melamine resins, nylon polyamides, acetal copolymers and acrylic copolymers have all been studied. Until 1981 none of these materials showed more than minimum promise. The ideal engineering plastic had to demonstrate a large number of properties, such as: a. High mechanical strength without brittleness. b. Excellent chemical, creep and permeation resistance. c. Adaptability to production technology. i. Injection molding, ii. Injection blow molding, iii. Ultrasonic or spin welding, iv. Decoration methods. d. Design flexibility. e. Moderate to low cost. No single plastic appeared to possess this panorama of characteristics. In some instances the problems could be moderated by imposing limitations on container size, wall thickness and design features. Or they could be reduced by modifications in chemical composition. The use of internal spray linings also helped. Newer bottle-making methods made it possible to produce containers from a wider range of plastic materials. And finally, compatibility problems could be minimized by imposing certain requirements on the aerosol formulation. Even with all these sophistications there are only a few plastics which are viable for use as aerosol containers. At the beginning of 1972, plastic containers still remained almost entirely in the development stage.
138 The Aerosol Handbook r Figure 1. Plastic and Glass Aerosol Containers All units are molded from Ceicon plastic, except the glass bottle, second from right. Plastic containers with one-inch openings were produced by Union Carbide Corporation during the mid-1970s, but never went beyond test market. The other containers are fitted with a 20mm valve ferrule, but with the alternate of omitting the ferrule segment and either spin-welding or sonic welding the plastic valve body directly to the flared bottle neck finish. Only three or four plastics were being investigated to a significant extent: a. Specific grades of Ceicon resin, Celanese Plastics Company. A highly crystalline, thermoplastic acetal copolymer of trioxane, produced by advanced polymerization techniques. b. Lopac. The Monsanto Company. A rather brittle copolymer of acrylonitrile and styrene. c. Barex. Vistron Corporation. About 80% of a copolymer of acrylonitrile and methyl acrylate, plus about 20% of a butyl rubber matrix component. d. (Name withheld). A copolymer which softens in contact with humidity or water; used as the core material for lined and coated bottles. Perhaps the greatest effort toward the development of plastic aerosol bottles was at that time put forth by the Celanese Plastics Company, at their Newark, N.J. facilities. A variety of bottle sizes and shapes have been made by Celanese since 1971 or so. The earlier types were barrel-shapes, finished to accommodate a standard one-inch valve cup. Sizes were three to six ounces overflow. The appearance of the unsightly valve cup largely destroyed the aesthetic appeal of the finished unit, so that efforts were then directed more toward bottles with the 20 mm ferrule type closure. A three-ounce bullet- shape (round), four-ounce flat oval (oval) and six- ounce tapered oval (oval) are examples of Celanese bottles using the 20 mm closure. About 1972 the company produce bottles with a finish designed for valve attachment by ultrasonic welding — the neatest seal of all. Those bottles included a five-ounce pistol-grip (oval), three-ounce bullet (round) and a three-ounce hourglass (round). Other designs were also prepared to show the considerable molding capabilities of Ceicon plastic. Four other firms have produced Ceicon bottles. Perhaps the most well known was the Minisol Division of the Pelorex Corporation. These bottles, so far produced only as the half-ounce (15 ml) one-ounce (30 ml) mini- barrel, were successfully market tested by Faberge, Inc. as the container for their line of "Purse-Pouf" hair sprays. Near the end of 1971 the Pelorex Corporation entered into an agreement with the Seaquist Valve Company, whereby Seaquist would assemble and decorate the Minisol containers at their plant near Cary, Illinois. During 1972 the first high-speed filling line designed exclusively for filling plastic bottles came into existence at the Rayette-Faberge, Inc. plant in St. Paul, MN. This line, reportedly built and installed jointly by Pelorex and Seaquist at a cost of about $300,000, was sold to Faberge and initially used for the production of'' Purse- Pouf" hair spray. Some 10MM "Purse-Poufs" were run at St. Paul, and marketed in July, 1972. Three-ounce Ceicon bottles of an elongated barrel (round) design were developed by the then Wheaton Plasti-Cote, Inc. They were designed to take a standard 20 mm ferrule valve. As a unique feature, the rim of the bottle finish was molded with a deep horizontal slot. When the ferrule is crimped onto the split finish area, the two vanes of plastic distort together slightly at the outermost edge. Afterward, the plastic exerts a permanent tensile effect upon the ferrule, tightening it against the rubber gasket to produce a seal of high integrity. Wheaton then developed manufacturing technology for a five-ounce elongated barrel (round) for introduction in late 1972. A one-ounce Ceicon bottle was later made in several designs by Cypro, Inc. (Hempstead, MD). Some designs were quite unique. Finally, the Citation Plastics Division of Jomar Industries, Inc. (Pleasantville, NJ) introduced a two-ounce Ceicon bottle using a unicavity mold. Work toward the development of aerosol bottles using plastics other than Ceicon was also quite active, both in the United States and in Europe. The Continental Can Company produced an experimental round,
Plastic Aerosol Containers 139 opaque plastic bottle from a thermosetting resin, which they called their "19 ml" container. It was tapered slightly, with the top somewhat larger than the base. The finish accommodated a special 26 mm valve ferrule. It has now been discontinued. Union Carbide Corporation and several other firms have produced plastic aerosols in either research or pilot plant quantities. Much of this work was of a confidential nature, but one of these new plastic bottles was unveiled during a commercial production run at the Peterson/Puritan, Inc. filling plant in Berkeley, RI in April, 1972. Aerosol historians may consider 1972 as the year plastic bottles became a market factor. Certainly there was every indication that the reception and growth of these new containers would position them as viable competition to other aerosol packaging forms. But unfortunately, as time passed along, they failed to achieve this initial promise. They were considered too lightweight and "cheap" for the cologne and perfume aerosol market, expecially when compared to heaviness and transparency — and even the cool feel and elegance — of glass. Only very small sizes could be made within reasonable economic boundaries, and as a result, with rare exceptions, only bottles with capacities of one-ounce (30ml) or less became commercial. The Celcon bottle is still available, and is being sold in 1982. One example is a % Av. oz. (22 g) Celcon container of Candlelight cologne, marketed by Take-Along, Inc. of Buffalo, NY. The bottle is natural Celcon, with black silk-screened decoration. The valve is integrated in the dome and body shell and covered by a full diameter silvered polyethylene friction cap. The base is spin- welded on. An illustration is provided as Figure 2. Basically, during the period of 1972 to 1980 the plastic aerosol business stagnated at a very low level and a number of the manufacturers and marketers simply turned their attention to other areas of involvement. But in 1981, some new developments came to the attention of the industry, which promise to have a profound effect upon it during the decade of the 1980s. The most important of these is the "OPET" type container. The OPET Plastic Container The acronym OPET stands for oriented polyethylene terephthalate. This basic and essentially 100% pure plastic composition has been known for many years under such trade names as "Mylar" and "Dacron". In Europe, during mid-1981, it was injection molded sue- If I ! f Figure 2. Cologne in Celcon Bottle "Candlelight" aerosol cologne, packaged in a Celcon 1-fluid ounce (30 ml) bottle with integral valve assembly and plastic silver-metallized cap. Marketed by Take-Along, Inc., Buffalo, NY. cessfully to make aerosol tubes about 1.15" (29 mm) in outside diameter, 1.00 " (25.4 mm) in inside diameter. The bottom end was sealed, using a spin-welded or sonic-welded disc, and the top contoured to mate with a standard one-inch (25.4 mm) valve cup, where the outer edge of the cup was rolled inward, into a groove in the tube, to effect the hermetic seal. The first samples of this revolutionary package appear to have been distributed by Aerosol Services, A.G., of Mohlen, Switzerland — a firm long recognized for their innovative expertise. The Aerosol Services dispenser was a hand cream, where the thick lotion was contained in a very thin aluminum tube, almost equal to the inner diameter of the plastic tube and only slightly shorter. It had a top flange with a rubber flat-ring gasket. To produce the package, the plastic tube was cooled and then about 2 ml of iso- butane propellent added by simply pouring it in. The filled inner aluminum tube was then inserted into the plastic one, after which the aerosol valve was pressed into place and the cup attached to the plastic tube by a roller-clinching operation. The plastic tube is thought to be PET, the non-oriented form of OPET, in its clear microcrystalline form. In 1981, at least two programs were started in the U.S.A., designed to modify the recently introduced OPET two-liter carbonated beverage bottle into a suitable aerosol container. By early 1982, a one-pint (473 ml) prototype container had been injection/blow molded by the Sewell Plastic Company. A sketch of this interesting development is shown in Figure 3.
140 The Aerosol Handbook Injection molded neck - Top-carrying ring Biaxially oriented polyethylene terephthalate blow- molded bottle protion High density polyethylene snap-on base section Figure 3. Sketch of OPET Plastic Aerosol Prototype model of plastic aerosol container, OPET, offered by The Sewell Plastics Company, Atlanta, GA. Decoration of OPET bottles can be handled by hot stamping, dry offset, silk-screening, heat transfer labeling. The manufacture of this bottle is a complex process. The best approach is to injection mold the neck section, leaving a base of plastic to be formed later into the bottle section. The injected structure is taken out of the mold and cooled. It has about 30% crystallinity and 0% orientation. It is then placed in an oven while protecting the neck section from heating, but allowing the base core to reach a predetermined temperature. The temperature is selected with great care to get formability, but only by the application of considerable force. In other words, the plastic is not melted, but heated only to a softened condition. The structure is then placed in a special blow molding machine, where a stretch rod first forces the base core downward to the bottom of the bottle mold. The rod is withdrawn and a pneumatic pressure of about 50 to 80 psig (344 to 552 kPa) is applied to stretch the plastic horizontally into the shape of the mold. In this fashion the plastic is biaxially oriented, first by stretching it vertically and then by stretching it laterally, which acts to strain harden it. If the mold is not a rounded type, so the plastic can blow out smoothly and evenly, much higher pressures must be applied. The petalloid base shapes often molded by the Continental Can Company, where the bottle rests upon several large bumps around the periphery, have to be made using up to 600 psig (4.14 MPa). Bottle shapes are also restricted to within certain limits of axial stretch and radial stretch if the plastic is to orient evenly and well. The PET material is highly crystalline. It is necessary to keep the crystals small so the bottles retain transparency and have good strength. If the plastic is overheated the little crystals will coalesce to form much larger ones called spherulites, separated by amorphous areas. Molding temperatures and times are controlled carefully to minimize any spherulytic crystallization, as well as to increase the degree of crystallinity by heat setting. OPET botdes achieve their best properties in the evenly biaxially oriented form. The non-oriented bot- de, such as the small sizes made by Wheaton Aerosols Co. and other firms, develop only about 60% of the barrier ability of the oriented bottles and are relatively brittle. They can be made by straight injection blow molding. The degree of orientation of OPET bottles can be measured by optical birefringence techniques. An alternate method for OPET bottle manufacture involves die use of die Neissi Company's four-station injection blow molding machines, which have a capacity of 5 to 6 million units per year per machine. Ware made by this continuous four-stage process is said to be slightly inferior to that made by the two step method just described, since any temperature deviations or inhomogenieties developed in die injection phase cannot be gotten rid of before the blow molding phase takes place. The initial tool cost of the Neissi operation is lower per machine, but when it is considered that from 2 to 4 of these machines are required to match the 11 to 20 million unit per year capacity of the two step equipment, the costs appear to be comparable. Spin welding has been suggested as a process for the attachment of valves to OPET bottles. It can be done, but not as well as in the case of polystyrene and a number of other plastics. Such a technique, if it can be developed, would allow the industry to eliminate tiie present valve cup and valve cup gasket costs. But that is for the future. The base area of OPET bottles must be made in rounded form. Either the regular or petallized profile will work for aerosols, but the regular rounded form is preferred. If the bottom were to be made like that of ordinary glass or plastic bottles, the pressure of the aerosol (or beverage) product would slowly overcome the creep resistance and cause the area to become slightly convex, giving the bottle a wobble. To handle the problem a small, annular indentation is made around the lower wall area of the bottle and a high density polyethylene base is attached by a very tight snap- fit. This can be seen in the familiar two-liter carbonated
Plastic Aerosol Containers 141 beverage bottle, and the same process has been used in one of the prototype aerosol containers. Creep resistance is a possible problem with the neck area as well. In the beverage bottle it can have the effect of elongating the plastic screw threads, causing the metal cap to bind to some degree. However, these units normally have such short (usually refrigerated) shelf lives that the problem never becomes serious. For the aerosol container, creep resistance can be improved by introducing different crystallization modes and, of course, by making the walls thicker. The pint (473 ml) Sewell bottle has a neck thickness of from Vb " to 3Ae "(3.2 to 4.8 mm). The large ledge of plastic near the top of the Sewell bottle is for top-carrying purposes, and is comparable to that used in the carbonated beverage bottle. It probably is not really needed for the pint size (473 ml) bottle. Either a much smaller collar or nothing at all would do. But, it would be somewhat more useful on the nominal 24 oz. (793 ml) container when this size is developed. Valve attachment has not been fully resolved. There is no way to injection mold an annular groove into the inside neck area of the bottle so that the aerosol valve can be crimped in place, more or less like it is in metal containers. This groove would have to be made in a separate machining operation, which would add to the cost. In addition, the outward pressure vector from the crimp might eventually lead to stress cracking, unless outward creep would occur rapidly enough. The best method is to mold an annular groove into the outside neck section and clinch the valve mounting cup inward, into this area, using either a multi-tine clinching collet or a three-wheel rotary clincher. The clinching operations could probably be done by the U-t-C gassing equipment now a part of many aerosol lines. The pressure resistance of OPET two-liter carbonated beverage bottles, which have wall thicknesses of about 0.015 "(0.4 mm), is at least 150psig(1.03 MPa) at ambient temperatures. In fact, this is a critical test, which must be passed by these containers. In the case of aerosols, a wall thickness of about 0.030" (0.8 mm) appears optimum, since pressures can get at least 50% higher than the highest carbonated beverage pressure levels, and in addition, higher temperatures are statistically more likely to be encountered. The two-liter carbonated beverage bottle, if well made, can be dropped from 15 to 18 feet (4.6 to 5.5 m) onto a hard floor without breakage; above this the bottles will split slightly and sometimes tear to some degree. They normally cannot be smashed by hurling them at a hard surface. These same properties should be easily accommodated for aerosol OPET containers. Product permeability is a function of OPET crystallization level, orientation level, thickness and the formulation. Permeability increases with temperature, as would be expected. There is substantial absorbtion of both CO2 and O2 into the plastic, even from the air. Such firms as Continental Can Company, Owens-Illinois, Hoover, Sewell Plastics, Amoco and Monsanto can provide permeability data for particular solvents. Extensive programs are underway to reduce permeability. For example, a large wine manufacturer has been working with one OPET supplier with the aim of applying a Saran barrier to the outside of these plastic bottles. In general, permeation is not a significant problem. Decoration of OPET bottles can be handled by hot stamping, dry offset, silk-screening, heat transfer labeling, the B&H type wrap-around labeling process and so forth. In the last, labels are applied at speeds as high as 300 to 400 per minute to bottle areas totally coated with a special hot melt adhesive. I Figure 4. 1982 Prototype of OPET Bottle An early aerosol bottle of about 16 fl oz capacity, made of biaxially oriented polyethylene terephthalate (OPET) by a Chicago firm. Undergoes excessive creep with higher pressure formulations, and at temperatures about 120°F (49°C) with most aerosol formulations.
142 The Aerosol Handbook OPET botdes are essentially 100% polyethylene ter- ephthalate in composition. There are no fillers or other additives. As the material is processed, the macromole- cules tend to spallate off various moieties from the ends, most notably acetaldehyde (CH3CHO). Thus the material has a slight acetaldehyde content. The trace amount of this simple aldehyde has not prevented the use of OPET for various food products. Bottles are not made from reprocessed OPET. The present cost of bulk OPET plastic is about $0.60 to $0.62/lb ($1.35/kg) in 1982, with the industry at about 60% of capacity. If the industry gets to 90% of capacity, die price will rise to about $0.75/lb ($1.65/kg). Aside from capacity influences, the price is expected to rise at about 6% per year due to inflation and related factors. The cost of a pint size (473 ml) aerosol bottle is estimated at $0.20 to $0.25 per unit in 1982. Other Modern Plastics There are at least three other plastics that are being looked at for aerosol applications. Their identities are proprietary at mis time. But improvements are being made every year in die area of engineering resins, and new products are coming out with some frequency. An engineering resin is roughly defined as one having a tensile strengui greater than 5000 psi (34.5 MPa), a modulus (stiffness) in excess of 100,000 psi (690 MPa) and a heat-deflection temperature of at least 130°C (266°F). For example, General Electric's Ultem 1000 unreinforced natural polyetherimide resin, at $4.25/lb, still has potential in smaller size containers. It is one of die finest plastics available and also flame retardant without being halogenated. Improved nylons, PET/PBT (polyemylene tereph- thalate/polybutylene terephmalate alloy), polycarbonates, polyphenylene oxide, polyacetals and other resins all show promise as possible aerosol container materials. Improved blends and molding techniques promise to extend the applications of many plastic materials into new fields, such as aerosol containers. In many cases there is leverage toward larger containers from a price standpoint. As plastic containers move into the aerosol market during the decade of die 1980's, diey will probably begin witli large bottles for water-based type products. DOT regulations forbid the use of non-metallic containers for flammable aerosol products in capacities of greater man 4 fl. oz. (118 ml), except by special exemption. An exemption has been granted to a plastic coated glass bottle in the 5 fl. oz. (148 ml) range, and work is now underway to secure exemptions for plastic containers. It is difficult to say how long or successful this activity will be, with such relatively large dispensers involved. There are mose who predict that 25% of all U.S.A. aerosols may be packaged in OPET and perhaps other plastics by 1986, and a majority of aerosols by 1990. This is certainly a possible scenario, but will depend largely upon the comparative economics of metal versus plastic containers in future years. Properties of Plastic Aerosols To be useful as aerosol container materials, plastics must exhibit a wide variety of desirable properties. These are often taken for granted in the case of steel, aluminum and glass. In some instances, plastics can provide these prerequisites and then go further, conferring such things as freedom of shape and a warm feeling, which metals and glass cannot convey. Fabrication Ideally, the plastic should be adaptable to extrusion blow molding, injection blow molding or injection molding. Celcon and OPET can be molded by any of these procedures. They allow the preparation of containers in a multitude of shapes and colors; and with special surface effects, such as slightly embossed or debossed designs. Plastics that can be injection molded are sometimes fabricated into finished containers by the attachment of two separate pieces. The Celcon bottles made by die Pelorex Corporation have the base ultrasonically welded to the body. The hermetic weld has the tensile strength of virgin plastic and the container will withstand up to 700 psig in the case of the one ounce (30 ml) size. In the past, nylon and Zytel (duPont) botdes were joined around the middle by spin welding. This particular treatment had the disadvantage of always leaving a definite weld ring uirough the center of die printed wall area. Also, spin welding can be used only on round containers. Other bonding techniques are available, including the use of special adhesives. But in general, strengths and chemical resistance obtained with adhesives leave something to be desired. Decoration Colors can be molded into the bottles in most cases, and sometimes striations and variegations, which add to die beauty of the finished unit. Celcon botdes have
Plastic Aerosol Containers 143 been made with molded-in textures, designs, colors and letters — features not obtainable in metal or glass containers except for a modest degree of expensive embossing and other texturizing in tin-plate three-piece cans. These molded-in features are more permanent than any present decoration on metal or glass. In addition, plastics can be decorated by printing (offset or silk screening) hot stamping, paper or foil labeling, or with transfer labels. The Faberge "Purse Pouf' Celcon bottles have been printed followed by flame treating to obtain maximum adherence to the normally very chemically resistant plastic surface. Silk-screen printing is effective on nearly all plastics, but is generally limited to one or two colors because of cost. Hot stamping, painting and vacuum metallizing can be done on most plastics by conventional methods. Paper labels can be used where the surface is flat or has only one element of curvature. Paper or paper-backed foil labels are attached by means of special vinyl or acrylic adhesives. The spot label technique, where essential data is inscribed on a circular label about 0.75" in diameter, attached to the bottom of the container, should also be useful for plastic aerosols. Finally, transfer labels of the "Therimage" type can be used. Size and Weight The plastics mentioned thus far exhibit densities extending from about 0.905 gm/cc (polypropylene) to about 1.410 gm/cc (acetal copolymer). Wall thicknesses vary according to type of plastic, bottle size, design parameter and other considerations, but are generally in the range of 0.030" to 0.075". The smaller plastic bottles may therefore be expected to be about equal to the weight of comparable sizes of aluminum aerosol cans and, of course, much less than the weight of glass or plastic-coated glass bottles. Plastic thickness increases as bottle size goes up. In the case of Celcon, which costs about $1.20 per pound ($2.50/kg) the raw material cost for a typical 30 gram flat oval bottle of four ounce overflow capacity is about $0,083, which is not inconsiderable. Similar considerations apply to all plastics. Design From a purely design standpoint the most efficient plastic bottle would be a perfect sphere. This shape requires the least weight of plastic per unit volume. As departures from the spherical shape become more and more pronounced, extra plastic must be used. In general, smooth curves and generous radii are recommended for maximum economy. Radical departures in shape, such as flat walls, should have the increased cost balanced by the possible marketing advantage of using such a shape. Certain guide lines are available for design considerations: a. Recommended attributes. i. Cylindrical shapes ii. Curved side walls, iii. Embossed effects, less than 0.010" deep. b. Attributes not recommended. i. Extreme ovals ii. Flat sides iii. Deep ridges, over 0.010" deep, iv. Small radius areas, especially for OPET. As container size increases, more and more attention must be paid to design attributes. Straight side walls which would be acceptable for a small container sometimes are difficult to use for a larger one without going to the expense of adding an extra plastic to compensate for the increase in hoop forces and other factors. As capacity increases, the side of a straight walled plastic bottle may have to become oval and then extremely oval. OPET is an exception, due to its extremely strong characteristics. Indirectly, this means that the ratio of the maximum to minimum diameters may have to move toward an eventual 1:1 or circular relationship. Bottles with highly curved side walls usually have small bases and shoulders, and this adds strength to the unit. Deformation may result as the effect of internal pressure on poorly designed bottles. Distortion may also be linked to permeability, but only for those resins which are swollen or plasticized by aerosol formulations. Increasing wall thickness adds a large measure of plastic strength and rigidity and is one method of reducing the effect of permeability. Poly- amide aerosol bottles displayed base inversion when holding certain formulations at 110°F for several weeks. By using a thicker base section, a less active formula, or a lower internal pressure, the problem of' 'rockers'' was avoided. Containers of Celcon and certain other plastics have the inherent flexibility of being readily formed with any type of neck opening configuration. Any of the standard one inch, 20 mm, 15 mm or 13 mm openings can be molded or post-machined on the containers. A
144 The Aerosol Handbook straight finish with countersunk opening may be used to match up with valves which are to be attached by ultrasonic welding. The valve body fits into the beveled opening like a highly tapered cork. This method of attachment provides an aerosol container in which no metal or rubber parts are in contact with the product. Base design of Celcon and other plastic containers must be given careful attention since this is the most impact-vulnerable area of the dispenser. The following base design criteria will help guard against impact fracture or base inversions: a. Recommended attributes. i. A radiused blend of wall to bottom. ii. Wall tapered into base, resulting in a smaller base area. iii. Inverted truncated and conical shaped base. iv. Programmed base — use of extra plastic where most needed. b. Attributes not recommended. i. Sharp base corners. ii. Flared out wall at base, iii. Flat bottom base, iv. Non-programmed base. The smooth transition of side wall into base provides more surface for impact than does a sharp corner. This is desirable because it diffuses the shock energy at impact. Sharp corners provide concentrating locations for molded-in stresses, making them doubly inimical to good container design and strength. The tapered-in base is remarkably stronger than the flared-out base, as can be shown from botde drop impact performance data. At impact the energy is concentrated on the corner of flared-out botdes and transferred sharply up the wall. Additionally, flared-out base designs preclude placement of sufficient plastic to the base corner. In the case of a particular Celcon bottle, only 0.025 " of plastic could be delivered to the flared- out corner, even with a maximum programming stroke. The reason for this is that the parison tube must be stretched a great distance, which decreases wall diickness. An equivalent container with tapered-in base received up to 0.070" of plastic, giving it very satisfactory impact performance. The strongest base, of course, would be a perfect hemisphere, but such a botde would not be self- supporting. The practical next choice is men an inverted cone. In order that sharp radii can be avoided and a minimum of material used, a wide angled truncated structure is recommended. In Celcon blow molding, a parison tube may be extruded into the mold and plastics subsequently blown into the configuration of the mold. Certain parts of the bottle become highly stretched because of the distance they must travel upon being blown outward against die mold wall. One of these critical parts is the base. Extra heavy material distribution in the base can readily be achieved wim only a minimum increase in botde weight as a consequence of efficient programming. For well designed bottles, programming can be used to at least double the base thickness. For bottles in the three to six- ounce range, minimum base thickness will vary from about 0.060 " to 0.080 ". Oval base designs require 10% to 20% additional plastic thickness, compared with the corresponding circular base configuration. Staining Aerosol formulas which contain darkly colored perfume oils as well as certain other materials are known to stain nylon and Delrin containers. These effects are also encountered with aerosol valve stems and bodies made from such plastics. Celcon and OPET are not affected. Interior coatings with Saran (vinylidene chloride — vinyl chloride copolymer) and other relatively impervious plastics greatly reduce both staining and permeation effects. Plastic staining is generally a slow process, becoming noticeable in a mondi or two, and reaching a maximum intensity after about six to twelve months. Nylon bottles filled with a cologne containing 5% per- fumeoil,45% ethanoland50% P-12/114(10:90)were found to be stained twice as fast and three times as deeply at 105°F as at 70°F. The staining occurs principally in areas of liquid contact. The two best cures for staining have been to use internal linings, or to use colored or opaque bottles. Impact Resistance By impact resistance is meant the ability of a filled bottle to resist failure when dropped. (A better term would be impact performance.) In the Celanese Laboratory a standard procedure and performance requirement has been developed for screening new bottle shapes. Filled bottles are dropped onto a steel plate from a collapsible six foot platform. No more than 5.0% of the containers must break when they are dropped on their most vulnerable position. Bottles
Plastic Aerosol Containers 145 which fail may be corrected by the use of additional plastic. Anodier consideration involves die minimizing of molded in stresses, such as by optimizing melt and mold temperatures and output cycle during the molding process for that particular bottle. Typically, Celcon containers exceed ten foot drops with no breakage. The three-ounce Celcon dispensers once offered by Wheaton Plasti-Cote, Inc. were said to provide 100% survival when dropped from distances of up to about 8.5 feet. This is far in excess of the performance of glass aerosols and most plastic-coated glass aerosols. As noted before, large OPET bottles can be dropped over 15 ft (5 m) without fracturing. Safety Plastic bottles generally provide a very good level of safety. Three considerations are paramount: what happens if the bottle is dropped in normal use, what happens if the bottle is dropped with sufficient force to cause breakage, and what is the result of excessive heating? We have mentioned that Celcon and OPET bottles will not break under normal drop conditions. If a plastic container is broken under unusual circumstances it will not shatter as does glass. Rather, in the case with Celcon, it will break into two or three parts, or for OPET it will develop a split, the Celcon parts will fly outward as the container pressure releases, but they are not massive or sharply pointed. They are not considered dangerous. When plastic bottles are dirown into a fire or placed in a very hot environment, their relatively low melt point enables the heat from die blaze to melt a section of the bottle locally and allow the pressurized product to be released. The low thermal conductivity of plastics inhibits heating of the contents to an intolerable extent before sufficient softening can take place. Escape of the contents through a relatively small hole may cause a minor rocket effect, but this is not highly dangerous, at least for non-flammable formulas. Most plastics will soften to content release levels at 225°F or below. Celcon softens at a still higher termperature. Organoleptic Compatibility Aside from the effects of solvent permeation, storage of many scented products in unlined plastic containers presents an odor stability problem. Tests were conducted in nylon bottles held six mondis at room temperature, with the finding that die fragrance of colognes containing oriental, aldehydic and floral perfumes was definitely downgraded, compared with standards in glass. A citrus fragrance was good, but less intense. A similar test was made in Delrin. Here only slight differences were noted against the controls, but there was a general weakening of the top note or' 'dry-out" note for about half the products tested. Plastics used for aerosol bottles must never contain plasticizers, since these can be leached out to various extents, creating odor problems, as well as problems for the container itself. In some instances, ingredients are present in the aerosol formula which act as plasticizers. Water is a plasticizer for polyamides, while hydrocarbons and aromatic substances are plasticizers for polypropylene. Celcon cannot be plasticized, nor can OPET. Plasticizing is one of two effects which cause container distortion. The other is lack of creep resistance. (To be accurate, pressure may also cause minor distortion, as a function of design and wall thickness. For instance a flat, diin side will bulge more than a curved, thicker side wall.) Celcon bottles have been tested for compatibility widi a number of fragrances. In a typical test, six perfumes were formulated as 4% Perfume Oil, 46% SD. Alcohol 39c (190 proof) Premixed, and 50% P-12/114 (10:90) and held under the following test conditions for about 20 weeks: a. Room temperature. b. 104°F(30°C) c. 122°F(40°C) d. Exposure to sun at room temperatures. e. Exposure to ultraviolet for five hours per day at room temperatures. f. 44°F(6.7°C) g. Freeze diaw, 23°F ( - 5°C) to room temperature weekly. (Six week test period.) Uncoated Celcon containers gave no evidence of major apparent adverse stability effects. Very slight organoleptic changes were noted, but controls in glass exhibited parallel effects. Permeation Personal deodorants, colognes and odier products have now been tested by a number of perfume houses, using bodi coated and uncoated Celcon bottles. In no case have any adverse fragrance changes been noted. Celcon appears comparable to glass.
146 The Aerosol Handbook Table I Permeation Rates Through 4-oz. Zytel 101 Bottles oj 0.050" Average Wall Thickness Composition 100% P-11 50%P-12& 50% P-l 1 100% P-12 100% P-l 14 40%P-12&60%P-114 100% P-l42b 100% P-l52a 100%P-226 99% Water & 1% P-12 Pressure at 75° F. 99% 95v% Ethanol & 1% P-12 99%Ethanol& 1% P-12 (psi-a.) 15 55 93 30 58 50 85 - 93 2 2 Weight Loss Per Year -0.38 gram -0.23 -0.27 -0.20 -0.03 -0.30 -0.25 -0.11 -10.30 -5.6 + 1.0 + = A gain in weight. - = A loss in weight. Table II Permeation Factors at Different Temperatures For Celcon Aerosol Containers (Grams/mil/day/100 in.2) Ingredient P-l 1 50% P-12 & 50% P-l 1 P-12 P-l 14 30% P-12 & 70% P-l 14 P-l 42b Ethanol (180 proof) 95% Isopropanol & 50% Water Propylene Glycol Dip ropy lene Glycol Acetone Methyl Ethyl Ketone Methylene Chloride 1,1,1 -Trichloroethane Trichloroethylene Kerosene (12% Aromatics) Ethyl Acetate Dimethyl Phthalate Tween20(HLB= 16.7) Water 75°F. +0.2 0.0 0.0 +0.1 +0.2 +0.5 -1.1 -0.5 +0.8 +0.4 -12.4 -3.3 - -0.5 -13.8 +0.1 -9.4 +0.7 -0.1 -3.6 100°F. +0.8 +0.2 - +0.5 +0.6 -0.5 -5.5 -2.8 +0.8 +0.6 - -10.1 - -0.8 -28.5 +0.1 -21.1 +0.2 -0.8 -11.9 120"F. + 1.9 + 1.1 - + 1.3 + 1.0 -0.5 -15.5 -7.3 +0.9 + 1.1 - -25.8 - -2.7 -56.6 +0.3 -40.1 +0.1 -3.3 -27.3 : A gain in weight. A loss in weight. All plastics can be permeated. Widi a plastic aerosol, permeation is a function of die material, the wall thickness, the surface area of die container and the temperature. Pressure (within the range of aerosol pressures) has little effect compared widi unpressurized systems. In some cases permeation can be very severe, as illustrated by the case of a four-ounce shaving cream, held one year at 100°F in a Zytel 101 bottle with 0.030 " average wall thickness. The containers lost an average of 24 grams during die year. The material which got tlirough die botde wall consisted almost entirely of water. Plastics differ gready in their permeability. Polyetli- ylene and polypropylene show a very high permeation rate for propane, isobutane and similar hydrocarbon gases, due to the chemical similarity and low molecular weight of tliese aerosol propellents. In contrast, remarkably low values are shown for certain fluorocarbon gases, such as P-114, P-115 and Freon FP-C318 (perfluorocyclobutane). The permeation rate can be expressed in terms of the weight loss from a given plastic bottle held at a fixed temperature, as in Table I, or it can be given as a nominal figure which can then be used to calculate the permeation to be expected for any size botde of any wall thickness. At the Celanese Laboratory the equation: p _ L x M x 100 in.2 d xA where: P = Permeation Rate; (gm/mil/day/100 in 2) L = Loss of Product; (gm) M = Average Wall Thickness; (mil) d = Time of Container Exposure; (days) A = Surface Area of Container, (in2) has proved to be quite useful. Since die permeation rate varies dramatically with temperature, and increases in a specific non-linear fashion widi temperature for every substance, all permeation rates must be qualified by the test temperature reading. For room temperature studies it is generally safe to predict that an ingredient permeating at less than 5.0 gm/mil/day/100 in.2 can be packaged safely in the plastic tested. This is equivalent to a weight loss of about 6% per year in a three ounce bullet (round container.) Specific ingredients which permeate at rates higher than this can still be packaged in plastic if they are used at low percentages and if a litde extra can be added to the formula to compensate for the higher loss. The most
Plastic Aerosol Containers 147 valid determinations are those made using the proposed formulation and bottle. Seepage through the valve and around the cup or ferrule must be added to permeation rate to provide a figure for total weight loss. As a rule the loss across a three or four month testing period can be directly proportioned to provide an extrapolated figure for annual weight loss. The Celanese Plastics Company has developed nominal permeation rate figures for some sixty possible aerosol ingredients, based on storage in diree ounce unpressurized Celcon containers for 24 months at 75°F (24°C), 6 months at 100°F (38°C), and 3 months at 120°F (49°C). Twenty of the more important ingredients are described in Table II. In many instances die permeation rate can be reduced considerably by the application of internal barrier coatings. A particular Celcon bottle which showed Computer Cost A Cost Factors ($/M Uni Input Table III nalysis for 2-oz. Celcon Bottle (1972 Basis) ts) Annual Volume (MM Units) Celcon Cost Spray Cost Labor and Salary Tooling Cost Rent Capital Variable Costs Celcon Spraying Printing Packaging Total Variable Cost Fixed Costs Labor Depreciation Tooling Supplies Maintenance Utilities Rent Other Total Fixed Cost **TOTALCOST Anticipated Production 20bpm. 9.125 29.21 0.00 23.60 1.64 4.37 13.77 29.21 0.00 5.00 1.38 35.59 23.60 1.38 1.64 1.18 0.55 2.39 4.37 1.38 42.12 77.71 Rate 40 bpm. 17.549 29.21 0.00 12.31 0.85 2.28 7.18 29.21 0.00 5.00 1.38 35.59 12.31 0.72 0.85 0.62 0.29 1.34 2.28 0.72 22.08 57.67 50 bpm. 21.936 29.21 0.00 9.85 0.68 1.82 5.74 29.21 0.00 5.00 1.38 35.59 9.85 0.57 0.68 0.49 0.23 1.11 1.82 0.57 17.71 53.30 a 6.0% annual loss of water without a coating gave results between 1.5% and 3.0% with a coating. This is a reduction of 50% to 75%>. Coated No. 501 Baby Barrels (5 fl. oz.) filled widi 60 ml of water and 10 ml of P-12/P-114 (40/60) were examined after ten months at 75°F (23°C) and showed a weight loss of 3.1 gm/yr, or 4.2% of the contents. Some of the propellent undoubtedly escaped through die one inch valve. The rest was water loss by permeation. (Losses due to propellent permeation are negligible in this instance.) The tables show diat some plastic aerosols gain weight during storage. This is explained by the pick-up of moisture from the storage environment. When more water penetrates into the container dian there is permeation of the product to die outside, a weight gain will occur. One explanation is advanced that diis occurs for hygroscopic products, and that the intake will continue until the product is fully saturated with water. This might explain the observed weight increase of nylon and Zytel bottles containing anhydrous ethanol, although the rate of weight gain slows considerably after only a few per cent of water builds up in die edianol. But it does not explain die phenomenon of weight gains when various propellents are stored in Celcon at about 70°F (21 °C) or above. Weight gains increase widi rising storage temperatures, at least up to 120°F (49°C). The solubility of water in these propellents is very low indeed. In the case of P-l 14 it is only about 0.005% at room temperatures. Chemical Compatibility Since plastics are organic materials, they are quite often adversely affected by organic solvents. A significant number of plastics are either weakened or dissolved by long contact with mediylene chloride at room temperatures. Fortunately, methylene chloride, forma- mide, acetone and other strong solvents are not used to any extent in those aerosol products which offer the most promise for plastic packaging. Plastics may also be affected by strong acids or bases. Nylon is affected adversely by long contact with strongly basic solutions, such as aerosol oven cleaners and certain specialy cleaners. Eventually the nylon may disintegrate into small shards, but this takes two or more years at room temperature. Nylons can withstand acidic solutions down to at least pH = 1.0 at room temperatures. Celcon plastic exhibits a good tolerance for all but moderately acidic products. Trouble may begin at pH =3.0 for some product types.
148 The Aerosol Handbook Marketing Aspects Because of the unique situation with plastics it will be necessary to conduct special compatibility tests on proposed formulas, but these studies should not take any more time than similar studies performed to audienti- cate other container types for new formulas. For the smaller marketer, the idea of utilizing plastic aerosols may be intriguing, but implementation may require fair amounts of both courage and money. Consumer purchasing factors are not yet well defined in die area of plastic aerosols. They are lighter than plastic- coated glass aerosols, but the larger OPET bottles are comparable to tin plate cans in weight. The light weight plastic might insert an impression of cheapness into the thoughts of the consumer (quite inconsistent with the normal retail price of die dispenser), and so impede purchasing. Colognes and perfumes packaged in glass will probably resist incursions by plastic aerosols, simply because they look quite elegant and feel cooler, heavier and more "solid". Plastic bottles in the one-ounce size will probably have to invade and capture the "traveler's market" to ever be really successful. These items have been designed for out-of-die-home uses, whedier for die weary salesman, die city-hopping executive, or the housewife out playing bridge or having dinner in a restaurant. The Faberge package consists of about V2 oz Table hair spray, designed to be carried in die purse as insurance against windblown or odierwise disarranged hair. The carry-around advantage of the small unit will have to compete widi die greater economies of much larger hair spray dispensers selling at about the same price. Disposal of empty products is safe in that there need be no fear of explosion due to incineration. It is also interesting diat the major products of Celcon and OPET combustions are simply water and carbon dioxide. This advantage can be promoted from an ecology standpoint. Plastic aerosols can be a serious potential problem in a warehouse fire if diey contain flammable formulations. They would be expected to react like RVR (or PRM) self-venting metal cans in this respect. Future Plastic aerosol containers have a definite place in the future of die aerosol business. Every refinement in polymerization technology and plastic bottlemaking expertise will widen the possibilities for marketing diese novel packaging forms. Since a number of large firms are now working on exactly these improvements, it is reasonable to anticipate that a significant market will eventually be captured by plastic aerosols. Sizes up to die U.S.A. limit of 793 ml should become available widiin two years. The containers should handle all the pressures now in use and many of the present aerosol formulations. IV Plastic Identification Table Plastic Trade Names Acetal Acrylic Acrylonitrile-butadiene-styrene (ABS) Cellulose acetate Cellulose nitrate Nylon Polycarbonate Polyethylene Polypropylene Polystyrene Polyvinyl chloride Polyetherimide Tetrafluoroethylene Diallylphthalate Melamine Phenolic Polyester Polyethylene terephthalate Polyurethane Urea Delrin, Dielux, Celcon Acrilan, Acrylite, Cadco, Crystalex, Cyrstolex, Lucite, Plexiglas, Zerlon Blendex, Cycolac, Lustran I, Abson Celacloud, Cellon, Fibestos, Hercocel, Kodapak, Lumarith Amerith, Cellophan, Fiberlac, Herculoid, Hycoloid, Pyralin Capran, Caplene, Chemstrand, Filon, Zytel Lexan, Merlon Agiline, Olathon, Ameripal, Durethen, Dylan, Poly-T Escon, Olefane, Poly-Pro, Olefil Amphenol, Dylene, Exon, Evenglo, Lustrex, Plio Tuf Boltaflex, Chemclad, Corvic, Diamond PVC, Duran, Durasol, Duratex, Flamenol, Naugahyde, Nygen-Tolex, Opalon, Pliovic, Tolex, Velon, Veloflex, Vinylite, Ultem Armalon, Dorlon, Fluran, Genetron, Teflon, Halon Dapon, Diall Cymel, Melantine, Permelite, Melmac Aqualite, Aquapearl, Arcolite, Bakelite, Beckopol, Durite, Beckacite, Tego Amaster, Apex, Aqua-glass, Amorex, Aropol, Duolite, Dypol, Glykon, Marco, Paraplex, Stypol, Vibrin, Laminae Mylar, Dacron, OPET, PETPAC, PET Arothane, Carthane, Daycollan, Vibrathane, Vulkollan Arodures, Avisco, Beetle, Daka-Ware, Rhonite, Urac
149 AEROSOL VALVES An essential element in every aerosol dispenser is the valve, which, when actuated, releases the product from confinement and allows it to go to work. Valves can be varied within surprisingly wide limits. They can deliver a very fine mist, a coarse spray, a very long stream, a foam, or even a viscous gel or paste. While most of them deliver the product at the convenient rate of about 1.0 g/s under ambient conditions, there are some that deliver as little as 0.2 g/s and odiers that run up to as fast as 80 g/s. In 1970 there were at least 15 valve producers active in the U.S.A. and an estimated 40 to 60 additional valve makers in the rest of the world. These numbers have now shrunk considerably. In the U.S.A. die following firms produce virtually all the aerosol valve requirements: Precision Valve Corporation Seaquist Valve Company Summit Packaging Systems Inc. ARC Division of Ethyl Corporation Dispensing Systems Division of Risdon Corporation Newman-Green, Inc. Emson Research, Inc. Clayton Corporation Sprayon Products, Inc. Avoset Corporation Leading foreign manufacturers include many firms owned, licensed or otherwise affiliated with various U.S.A. valve makers. A partial listing of larger operations would include: Metal Box Limited (Affiliated with Precision Valve Corporation) Valois, S.A. (French affiliate of Seaquist Valve Company) Aerosol Research Ltd. (English affiliate of Cope- Allman, Ltd.) 5
150 The Aerosol Handbook Reboul Sofra, S.A. (French affiliate of Cope-Allman, Ltd.) Coster Technologie Speciali (Italy) Solfrene S.p.A. (Italy) Deutzsche Prazisions Ventil Gmbh. (West Germany affiliate of Precision Valve Corporation) Newman-Green (U.K.) Ltd. (Wales, U.K.) Aervalv, S.A. (Mexico) Maruka Machinery Co., Ltd. (Japanese affiliate of Newman-Green, Inc.) The Vertical Action Aerosol Valve By far the most popular type is the vertical-acting, piston-type or push-down valve; usually just called die vertical valve. Probably 90% of all aerosol valves are made in diis basic design. The operating principle is very simple. The valve opens when the stem is depressed into the body and shuts off when it is released and springs back into place. When in the normal or closed position the stem is pressed upward by a metal spring. But when a sufficient downward pressure is applied the spring tension is overcome and die stem is forced downward. This serves to slide one or more horizontal stem orifices past the seat gasket and into the top of the valve chamber, which is under pressure from the product. The pressure dien forces die product through die stem orifice(s) into the vertical center hole of the stem and out through the valve button or spout. A typical vertical-action valve has seven basic parts: the actuator, mounting cup, stem, stem gasket, spring, valve body and dip tube. Only three move in relation to die odier parts: the stem, stem gasket and spring. Actuator The actuator may be a simple spray button, or it may be an integral part of various spouts or spray domes. As a rule, it not only allows the user to operate the valve, but it may also fulfill a major role in determining spray rate, spray pattern, particle size distribution and so forth. A very large array of actuators is available for dispensing sprays, foams and other product varieties. The actuators are almost always injection molded from polyethylene or polypropylene, using plasticizers and other components diat virtually eliminate any chance of cracking from stem tension. A number of design features are used. One, of course, is the size of the terminal orifice — where the product emerges from the dispenser. For sprayheads, die normal range is 0.013" to 0.030" (0.33 to 0.76 mm). The diameter is generally selected in a size diat is slighdy larger than that of the metering orifice in the valve stem to develop a spray of better and more uniform particle size distribution. The terminal orifice may be straight or tapered, and if tapered it may be either a forward or reverse type. In addition to the standard straight or tubular orifice, modified straight orifices are made by stepping the bore outward at a shouldering point, so that the end of die bore is larger than the beginning. Many of the "flat face" and powder spray buttons have bores that are widened near the end. If the widening takes place near the mid-point, and especially if the shoulder area is angled instead of square, the actuator will take on the properties of a "regular" or outward tapered type. Some actuators have a tubular orifice designed to accommodate a 0.090 " (2.3 mm) plastic extension tube of various lengdis. A tapered orifice will give a slighdy better break-up dian a tubular one, and the reverse tapered type will generally provide a slightly better break-up and somewhat wider pattern than either the standard or regular tapered profiles. Actuators may be specially formed and equipped with plastic inserts to aid in the development of particularly desirable spray patterns. In general, diey are called M.B.U. or mechanical break-up systems. A few are designed to produce jets and other unique patterns, but most M.B.U. actuators are used to eidier provide a spray with odierwise non-sprayable compositions, or to enhance the break-up provided by the propellent by adding a mechanical factor. In die case of starches or window cleaners, for instance, the products are about 90% water and they could not be marketed in aerosol form were it not for the ability of the M.B.U. actuator to break up the solid stream of liquid into an acceptable coarse spray. The insert component is forced into die enlarged orifice area of the actuator, where it often fits over a post that is channeled on the flat end. The product enters a peripheral channel, and dien goes into at least two and nearly always four offset radial channels that end at the insert orifice. The configuration acts to give die product a strong swirling action as it leaves die actuator. Taken by itself, this would result in a hollow cone type spray, able to produce a doughnut pattern on a surface. But if the offset radials are arranged correcdy and if a mixing or interaction area is provided, just below die terminal insert orifice, then product from the violent mixing area will tend to fill in die hollow area, and die doughnut
Aerosol Valves 151 type spray will change to a disc-like or normal spray. The technology of the turbulent fluid flow patterns in M.B.U. valves is still not understood completely and patterns are developed largely by empirical means. Dimensions are critically important in the channel area, as might be imagined. By selecting the correct M.B.U. button from the scores of available types, the formulator can produce a great diversity of spray patterns and probably, among them, some that are acceptable for his product. On the negative side, M.B.U. actuators are understandably higher priced than one-piece sprayheads, and they are also somewhat more susceptible to plugging problems. Not all M.B.U. actuators are two-piece assemblies. For example, the Precision Valve Corporation has been able to mold some acceptable one-piece types. More exacting control is generally afforded by the two-piece varieties. And finally, there are a few lines of what can be called quasi-M.B.U. actuators: one-piece spray- heads which provide more break-up than ordinary one- piece styles, yet less than the true M.B.U. systems. Mounting Cup and Cup Gasket The one-inch (25.4 mm) mounting cup, first developed and patented by the Bridgeport Brass Company in 1952, was one of the important early developments that helped make the aerosol package commercially practical. The cup serves to clamp the valve stem, stem gasket, spring and body together and at the same time provides an hermetic seal to the one- inch (25.4 mm) opening of the can. It also serves as both a platform and attachment area for most foam spouts, some actuator skirts and several types of overcaps and spray domes. About 90% of all U.S.A. aerosols use valves with tinplate mounting cups. The remainder carry various ferrule type valves and one-inch mounting cups made of aluminum. Aluminum aerosol cans may carry either ferrule valves, aluminum one-inch cups or tinplate one- inch cups, depending upon size and formulation compatibility aspects. Tinplate mounting cups are usually made of 100# base weight steel plate, so that the average thickness is thus 0.0110" (0.280 mm). Alternate 95# and 107# baseweights are also available on special order but are rarely encountered. The regular 100# tinplate will begin to deform upward at internal can pressures of somewhat over 320 psig (2.07 MPa), and will start to leak product through the crimped seal at about 375 psig (2.59 MPa). Since these figures exceed the deformation and burst resistance of virtually all tinplate cans and many aluminum cans, there is rarely a need to use heavier plate. Exceptions have been encountered for some cups with threaded (Vie "-20NF) hubs, for packaged refrigerants, and for heavy-duty aluminum cans and valves, designed to meet unrealistic Underwriters Laboratories pressure criteria for a few specific products such as fire extinguishers. Tinplate cups are available with various plating thicknesses. An 0.33# ETP specification is popular for cups that are epoxy lined. Most plain cups use 0.75# ETP. The use of tin-free steel (TFS) is being researched for eponed or Organosol/epon cups as a minor cost- saving measure. Such cups have a gray appearance. Because of this detraction they may find their initial use in applications where the valve cup is covered with a foam spout or spray dome. Aluminum mounting cups are about 0.016" (0.4 mm) thick, or about 1XA times as thick as tinplate cups because the metal is less resistant to deformation. They can be identified by their softer, hazier or less shiny surface appearance or by the fact that they are nonmagnetic. They are used only on aluminum cans these days, although in the past there have been some exceptions. Crimper settings must be revised to accommodate the greater thickness of aluminum valve cups. Aluminum cups are almost always epon protected on tops and bottoms. Where the product is unusually active, a stainless steel mounting cup may be used, but the price increase is very significant. The typical thickness of 0.0105" (0.267 mm). Most valve companies do not stock these special cups. They must be special-ordered, and there may be delays because of this. Some years ago special Figure 1. Flat and Conical Valve Mounting Cups The conical variety, on the left, is used to prevent cup impingement of wide-angled sprays for other special purposes. In the illustration the valve components are not yet assembled and staked in place.
152 The Aerosol Handbook laminated cups were made by at least two firms, die steel core being overlaid with thin films of Monel, stainless steel, aluminum or odier metals. A typical metal "sandwich" consisted of 0.002" Monel/0.008 " steel/0.001" Monel, with the heavier 0.002 " (0.05 mm) Monel layer facing the product. Plate of this type is still available but is of no current interest to die aerosol industry. A number of specific shapes have been used for mounting cup designs. The so-called "flat cup" and "conical cup" designs are illustrated in Figure 2. The conical profiles are often used where die actuator must be elevated somewhat in order to allow a wide- angled spray to clear die edge of the mounting cup without impingement and dripping. The portion of die valve cup that holds the valve assembly is called the pedestal. The cup pedestal is clamped securely over the valve body wall by means of a stake or clinch. The dimensions of this indentation must be controlled closely. If they are too loose, die valve may leak or show excessive seepage. If they are too tight or high, the stem gasket may be over- compressed, causing it to squeeze inward, toward the stem and make die valve hard to operate or to spray poorly. Most valves have different size bodies, and thus the pedestals have a variety of diameters. This becomes important for Through-the-Valve (T-t-V) gassing operations where die adapter makes a seal around the top wall of the pedestal. Many adapters will not handle more dian one, two or three valves because of this variation. The diameter of die one-inch (25.4 mm) hole in the can dome is specified as 1.000 ±0.004" (25.40 ±0.10 mm). In order to fit smoodily into the minimum diameter can plug, the diameter of the outer valve cup wall is specified as 0.991 ±0.003" (25.17 ±0.07 mm). This leaves a ring of at least 0.001 " (0.025 mm) to accommodate out-of-round conditions, die bottom feather- edge of Flo wed-In® cup gasket materials and so forth. In some instances, valve cups are produced with smaller outside wall diameters. For example die Precision Valve Corporation's nylon-liner cup has an o.d. of about 0.956 " (24.28 mm) since it is held within a lower sheath or lining of nylon about 0.20 ±0.002" (0.51 ±0.05 mm) thick, to protect it from discoloration by thioglycollates contained in depilatories, for exam- ®Registered trademark of the W.R. Grace & Company. Figure 2. Cross Section of a Typical Flat Cup and Conical Cup Valve CONICAL CUP STEM STEM OKIFICE MOUNTING CUP CUP CASKET DIMPLE STEM GASKET BODY VAPOR TAP HOLE BODY OK1FICE DIP TUBE u: -POWDER STEM FEATURE -STEM -STEM ORIFICE ..MOUNTINC CUP -CUP GASKET -DIMPLE -STEM CASKET -BODY -VAPOR TAP HOLE •BODY OKIFICI-: -DIP TUBE
Aerosol Valves 153 pie. The cup o.d. has to be made smaller to accommodate the liner and still fit within the can orifice. In a potentially much more important example, the mounting cup used widi the Precision Valve Corporation's polyethylene sleeve development must have an o.d. of 0.965 ±0.003" (24.51 ±0.07 mm) to make allowance for the PE-sleeve, which runs about 0.0125 to 0.0140 " (0.32 to 0.36 mm) in thickness. The PE-sleeve is designed to replace the more conventional GK-45- NV and NVH type Flowed-In® gaskets as well as the buna, neoprene, Viton and other cut gaskets, but it differs from diem in that up to 0.014" (0.36 mm) of polyethylene is designated to hug the outer body wall. The Flowed-In® gaskets have only about 0.001 to 0.002 "(0.025 to 0.050 mm) of thickness in this area and the cut types have none at all. The PE-sleeve offers much promise as the future gasket of choice for the aerosol industry. It can be gassed widi both T-t-V and U-t-C (pre-set) machines and has the following set of advantages: a. Lower cost and low anticipated future costs. b. No possibility of EPA actions under the Clean Air Act, as may be the case for other gasket compositions. c. Can be made to significantly closer dimensional tolerances than other gaskets. d. Shows very low clinch leakage, even with very high solvent systems. e. It produces a cork-like vertical seal, plus the regular seal in the arch of the cup. f. Gasket flaking (which may cause valve clogging) does not occur. g. Latent leakers are avoided. The gasket is specially compounded from low density FDA grade polyethylene, nominally 0.014 " (0.36 mm) thick. Because of the tension at the upper cut edge area when in place it has had to be formulated in such a way as to be highly resistant to environmental stress cracking. The gaskets are made in Precision Valve Corporation's Aeroclo Division plant in New Jersey, using the following six-step process: a. The polyethylene, in prilled form, is melted and extruded into tubes. b. The tubing enters a six-station machine, where it is first cut to length and placed onto die valve cup by controlling and feeding arbors. c. It is driven home, into the cup arch. d. It is conditioned for the final forming operation— tucking into die curl. e. The height of the sleeve and other dimensions are checked with mechanical fingers. f. Finished valve cups are bulk packaged for storage prior to assembly of finished valves. Actually, dimpling (three unusually large outward dents just below the bottom edge of the sleeve) is now performed on die valve assembly line, but will later be done immediately after die checking operation (step e.). The dimples are extra large since they must protrude out past the sleeve and make a distortion fit past the can curl diameter to enter the can slighdy and effectively hold die loose valve in place until die time it is crimped to die container. The equivalent diameter circumscribing die three dimples is about 1.013" (25.73 mm). As of mid-1982 Precision had the PE-sleeve gasket available in at least four cup variables and were working on additional ones, including an aluminum cup. The cup system has patent applied status at this time. The company has offered the development to other interested valve manufacturers. In addition to the change in cup wall diameter, other alterations are necessary to achieve final, after- crimping, stem heights. For example, die conical cup for PE-sleeve gaskets must be made deeper (0.228 " going to 0.238 ") to get the optimum stem height of about 0.304" (7.72 mm) after crimping, so that plastic full- diameter actuating components can be seated correctly for die best operational results. The stock used for these cups is normally 0.25# ETP 100# baseweight plate. Crimping dimensions of 1.070" (27.18 mm) diameter and about 0.181 to 0.185" (4.60 to 4.70 mm) depth seem to be optimum. The cup dimples have to be about 0.020 " (0.51 mm) lower dian normal in order to obtain a good vacuum in the U-t-C gasser. In 1982 (and for about thirty years previous), the GK-45 type Flowed-In® gasket was the standard, used in nearly all U.S.A. aerosol valve cups. The usual method of application involves pouring about a 50% dispersion of the neoprene-based material into the hollow of the inverted mounting cup, using a special nozzle, while die cup is rotating slowly. The pour period equates to 360° of rotation, although a 720° cycle has sometimes been used. After the pour, the cups are heated in three stages to drive off the solvents and chemically cure the elastomer. The thickness specifica-
154 The Aerosol Handbook tion is usually described as 0.022 ± 0.007 " (0.56 ±0.18 mm) on an Acceptable Quality Level (AQL) of = 0.25, but it is very hard to maintain this specification widiout constant surveilance. In addition, the gasket should extend downward along the cup wall to a distance of 0.175 ±0.015" (4.45 ±0.38 mm) below the crown or highest part of the mounting cup (K-dimension) widi an AQL of = 1.5. The wet or pour weight of the gasket is generally controlled to between 475 - 500 mg per cup. The GK-45 NVH dispersion is 60% solids. Several modifications of these dimensions and weights have been used, but always to a very insignificant extent. During the 1970s at least two valve suppliers offered cups with a so-called "double gasket". In this case die thickness was increased to 0.040 = 0.010" (1.02 ±0.25 mm) (AQL = 0.25) with a maximum thickness variation of 0.017 " (0.43 mm) per can (AQL = 0.25), and the gasket height was established as 0.195 ± 0.015 " (4.95 ± 0.38 mm) at an AQL of 0.25. Of more interest today is die "half-diick" gasket, widi a wet or pour weight of 225 to 250 mg per cup. It often holds swelling-type formulations, such as methylene chloride types, more effectively dian the standard gasket, and also generally costs about $0.50/M. less. Another variation is the "low-lined" gasket, available from Summit Packaging Systems, Inc. in both regular (445 to 475 mg) and "half-thick" varieties (225 to 250 mg - tentatively). The low-lined profile requires a change in pour nozzles and is designed to provide extra gasket compound at die vertical wall of the valve cup. It is also very effective for holding a number of products to a very low annual weight loss range. Until about 1973 die GK-45 composition, by die Dewey & Almy Division of W.R. Grace Co., contained NA-22, a 2-mercaptoimidazoline curing agent made by E.I. du Pont de Nemours & Co. But about that time, evidence came to die FDA diat the additive might be a chemical carcinogen. Aldiough die calculated amount of unreacted imidazoline that could enter die product was only about 1 x 10"8 %, the FDA (in a housekeeping measure) asked that it be removed from bodi the stem and cup neoprene-type gaskets. This was done. Very high boiling, non-volatile esters were used to replace die imidazoline derivative. Depending upon the selection of additives, the GK-45 material was dien revised to GK-45 NV and GK-45 NVH. The properties of these two substitute elastomers were highly comparable, so that diey were often used interchangeably. The GK-45 NVH is currently by far the most popular. In the case of the cup gaskets only a small sacrifice of sealing properties had to be made in the transition, but die quality downgrade was somewhat more serious in die case of neoprene stem gaskets, since here a flexing action was involved also. Several odier poured-in cup gaskets have been advocated by the Dewey & Almy Division in recent years. A general problem with die GK-45 types is tfiat they either swell or shrink excessively with some aerosol products, they require rather high and long curing oven temperatures, and they contain toluene and other solvents that are driven off during curing, to die consternation of the EPA (Clean Air Act) and OSHA (from possible worker exposure). D&A's GK-70 was of interest for a time in diat it did not shrink with such compositions as ether or ethanol/P-12 personal deodorants and disinfectant/deodorants, but when P-12 was removed from the U.S.A. aerosol market the materia' went into a decline and is now an almost extinct special order item. Water-based latexes have been under intense development for several years because of the environmental and possible healdi concerns relating to toluene cook- offs during curing of the solvent-based types. They are also less costly, and presently run about $1.15/lb. ($2.54/kg). D&A's Cap 5520 and W-1809 waterbase mounting cup compounds have the properties listed in Table I. The D&A Cap 5520 latex emulsion was developed by the company's overseas division in Great Britain and has been run commercially by Metal Box Limited and odier European valve makers for many years. About 1979 an effort was made to introduce this product into the U.S.A. by importation from England. A major valve cup supplier in the Chicago area attempted to pour mounting cups with it but experienced a series of production problems. Marginally acceptable cups were finally produced, but still showed a certain amount of leakage, due to fish-eyes, voids, poor cup adhesion, pin-holding, rippling and in general a non- homogeneous lay-down of die elastomer. However, cups hand selected for good quality pours gave better performance than GK-45 NVH cups, in the case of formulations high in methylene chloride. The reason for die U.S.A. production problems have never been explained. They may relate to pot-life, to cooling of the drums during trans:Adantic air ship-
Aerosol Valves 155 ment, or to other factors. At any rate, the final result is that this emulsion is no longer offered in the U.S.A. The D&A Darex W-1809 latex emulsion, made at the Dewey & Almy Woodbury, NJ facility, represented an attempt to produce a product essentially equivalent to the European Cap 5520 material. It became available commercially about 1978. Testing revealed that cup adhesion and solvent resistance were inferior to GK-45 NVH, and that some exudation occurred with CO2 packs and other higher pressure formulas. In the case of formulas containing 20 to 70% of methylene chloride, weight losses were less than those found for GK-45 NVH. A lower shoulder placement was required, up to 0.016 " (0.040 mm) above the valve skirt height, in order to prevent the compound from oozing into the container during the heavy compression stage immediately prior to U-t-C crimping. Table I Properties and Recommendations for D&A Cup Latexes Attributes Cap 5520 W-1809 Physical Properties Color (Liquid) Color (Dried, cured solid) Viscosity (cps at 77°F or 25°C)* Total Solids (%w/w) Specific Gravity (wet) Specific Gravity (dried film) Durometer (Shore A) Diluent Lining Conditions Nozzle Size Air pressure (psig) Film Weight (wet) (mg) Film Volume (dry) (gauge) (inch) Shoulder placement Lining speeds Curing Cycle Red Red 2900 to 4000 83.5 to 84.5 1.96 2.42 — Water 54 drill 10 to 20 650 to 675 0.028 0 to 0.016" above curl Slow Red Red 2300 to 2800 82.5 to 83.5 1.94 2.34 74 Water 56 drill 10 to 20 600 0.025 Even with curl Slow 15 15 Air Dry (max.) (minutes) Time per Zone, and Temperature °F) Zone 1 30 at 135 30 at 130/135 Zone 2 30 at 155 30 at 150/155 Zone 3 30 at 195 30 at 190/195 Price (S/lb in 80 lb pails - 1980) 85 88.5 FDA Status 1980 Applied for Approved 'Brookfield Viscometer, Model LVF, Spindle #3 at 60 rpm. In 1979, D&A learned that certain ingredients, including a critical emulsifier, were being discontinued in this country. In response, they abandoned plans to improve upon W-1809 and began researching new compositions that might equal GK-45 NVH's performance profile. During 1980, supplies of the discontinued ingredients became exhausted. It was not considered economically feasible to import European equivalents, so the W-1809 program was suspended. A third water-based cup gasket material is identified as the Wiederhold latex emulsion, or (more simply) WDH Compound or CAP 85-64. It is a red, viscous liquid made in West Germany and used in many European countries. In the U.S.A. it is available from at least two valve manufacturers on special order. Cured WDH gaskets are very sensitive to humidity and are able to absorb up to about 8% water. The material is relatively soft under any conditions, but with absorbed water it becomes even softer and more flowable under pressure. In many cases, WDH type valves, stored at 50% R.H., have shown a significant degree of ooze, or extrusion, when gassed and crimped by a U-t-C machine. The same valves, pre-heated in incubators at 160°F (71°C) to drive off the preponderance of any absorbed water, did not show any oozing. But even where enough gasket material squeezes out to give a severe draping effect the crimp seal integrity always seems to remain intact, with very low weight losses. The gasket material appears to adhere better to epon lined cups than to plain ones, but even on plain types it is better than D&A's Cap 5520. It is especially good for products high in chlorinated solvents, such as methylene chloride. There is a report that the material caused corrosion of bright, machine- finished aluminum can beads. The future of WDH latex in the U.S.A. is uncertain at best. There are concerns about pot life, and about the possibility of freezing the emulsion if it is airfreighted across the North Atlantic during the winter months, and perhaps even during the summer. A number of domestic productions have been made successfully, but if the PE-sleeve gasket lives up to present expectations it will do everything the WDH will do, and more cheaply as well. A number of firms apply poured-in gasketing compounds to valve cups. The largest is Handy Button Machine Co., with plants in Melrose Park, IL and New York, NY. They are said to produce about 1.2 billion units per year. Probably the next largest is the
156 The Aerosol Handbook Aeroclo Division of Precision Valve Corporation. Others include Bristol Flowed Gasket Co., Thomas Industries, Inc., and Sterling Seal Division. A few valve manufacturers also do some of their own pourings. The other major valve mounting cup gasket is the "cut gasket", which in Europe is called the "laid-in gasket". It generally consists of a buna, neoprene or Viton hollow disc. Dimensions vary somewhat, but the i.d. is about 0.985 " (25.0 mm) and the o.d. is roughly 1.142" (29.0 mm). The thickness was standardized in Europe about 1975, at 1.00 mm, or 0.039". In the U.S.A. a popular thickness has been 0.050 "(1.27 mm). Gaskets down to 0.025 " (0.64 mm) have been investigated, but below about 0.028 " (0.71 mm) they become too flimsy for easy handling. Aluminum cans with "eyelashed curls" have seemed to require a gasket thickness of at least 0.036" (0.91 mm) to be quite free from radial micro-groove seepage. An estimated 94% of the valves used in the U.S.A. and Canada use flowed-in gaskets, with cut gaskets being used only in particular product areas, such as some fumigants, many P-12 and P-114 refrigeration unit recharge cans, many of the larger diameter aluminum cans and a few other areas. Most valves in Japan and Australia used flowed-in gaskets. But in the rest of the world the most popular outer gasket is the laid-in type. An outstanding example is West Germany, where the ratio is 85% cut gaskets to 15% flowed-in gaskets, with valves being gassed by both T-t- V and U-t-C methods. In Europe, as a whole, it is estimated that about 60% of all valves carry the laid-in gasket, and that the percentage is steadily increasing. Originally the reason for using cut gaskets was the necessity to employ this type of seal to prevent the possibility of leakage in aluminum cans. Then it started to be used increasingly in the growing tinplate can market, because of its good performance and the problem of double inventories of both flowed-in and laid-in gaskets were to be maintained. The cut gaskets are produced from smooth-surfaced, flat ground rubber sheeting by means of a cutting lathe or by punch presses. In at least one instance, this general type of outer gasket has been molded, more or less in the shape of the top third of a laterally sliced doughnut, with a crescent top and flat bottom cross- section. Producers include American Gasket & Rubber, Inc., Bentley Manufacturing Company, J.B.L. Corporation, Vernay Laboratories, Inc. and (in France) Le Joint Francais, S.A. In the U.S.A. the most available laid-in gaskets include buna rubbers with Durometers of from 35 to 50, neoprenes with Durometers of about 65 to 85 and Viton fluoroalkane types. At least two Viton compositions are available. The most common is the brown type, generally 0.042 " (1.07 mm) thick, but there is also a little-known black variety with a thickness of 0.035 " (0.90 mm). The lower Durometer gaskets are much harder to handle on automatic placing machines, especially if they are relatively thin. In fact, one major valve manufacturer has standardized on an 80 Durometer buna in Europe, because of machine difficulties with lower Durometers and also with neoprenes. While laminated gaskets are very uncommon, sandwiches with low Durometer faces and high Durometer cores appear to have good machine handling properties, and the soft buna surfaces probably flow somewhat to make a still better hermetic seal with the valve cup arch and the can bead. At least a few million of these have been run with very good results. No blow-outs were encountered in U-t-C gassing tests. Like the flowed-in gaskets, cut gaskets have rather complex compositions. They contain the basic poly- chloroprene, buna-N (polybutadieneacrylonitrile), or buna-S ingredients that characterize the gasket type, but in addition there are softening agents, age protectors, ozone protectants, lampblack, organic and inorganic fillers, curing and vulcanizing ingredients and so forth, according to the chemical and physical properties that are required. Factors such as tensile deformation resistance, low temperature set and module of elasticity can be adjusted according to the additives used. For example, a West German qualitative formulation for a black, oil-resistant gasket with a Shore A hardness of 75 is as follows: Perbunan N (Buna N) Zinc oxide - activated PAN aging protector Paraffin Lampblack (soot) - Durex Lampblack (soot) - CK Plasticizer Sulfur Vulcanizer CZ In the optimum proportions, this composition gives a buna rubber with a typical tensile strength of 110 kg/cm2, a breaking elongation of 360%, an impact elasticity of 43% and a density of 1.25. In these com-
Aerosol Valves 157 positions it is important to minimize the free sulfur content, or bright machine finished aluminum can curls can be corroded, with the formulation of aluminum sulfide, AI2S3. In contrast to Europe, there is a significant lack of incentive to use cut gaskets in the U.S.A. The gaskets are not supplied already fitted to the valve cup and this process requires a hand labor operation. Then, in the hopper and sorter assembly of automatic valve inserter equipment up to about 1 % of the assembled cut gaskets may fall out. If they are undetected, obviously a gross leaker will result when the unit is gassed. And finally, it is difficult to use U-t-C gassing equipment with these gaskets without blowing some of them into the can, again resulting in a gross leaker. In the U.S.A..valves using cut gaskets are almost always gassed by T-t-V methods, since there has been little or no incentive to expand the technology. In Europe, T-t-V gassing was the standard method only until about the mid-1970s, but then, as the result of a special process said to have been developed by Precision Valve Europe, U-t-C gassing also came into widespread use. The basic technology is available from Precision, anywhere in the world, and it simply involves adjustments to the U-t-C gasser to establish a particular flow path for the propellent during charging. This optimum flow pattern results from strongly reducing the initial turbulent surge of gas-liquid into the container at the outset of the gassing phase. It is done by the use of needle valve flow controls, the use of relatively low propellent pressures, in the 400 to 600 psig (2.76 to 4.14 MPa) area, and by the use of sequential springs in the head. Gasket Leakage Considerations Valve leakage, through the crimped seal area, or through the seat or stem gasket area, has been the target of endless investigations. All aerosol dispensers leak to some extent, but those that leak excessively can bring about some serious commercial consequences. Ideally, leakage should not exceed about 0.1 Av.oz. (3 g) across a year of ambient temperature storage. Most aerosols fit into this category. Those that contain strong solvents, or sometimes those that have much higher pressures (such as C02 or N2O packs), may leak at up to about 0.25 Av.oz. (7 g) per year. Any dispensers that exhibit leakage rates higher than this should be monitored very carefully. Perhaps the crimping dimensions were incorrect, or possibly the formulation could be turned out just as well with lower percentages of strong solvents. A different elastomer might be required. These higher-leakage dispensers sometimes have the ability to hold the product well enough for several months, but after that period the seal may breach, allowing the can to depressurize in a day or two. These units are often called latent leakers and are unwittingly produced at the level of many millions each year. The conditions of storage often have a considerable effect upon weight loss rates. Dispensers showing low weight loss rates in the upright position do not generally change materially if they are laid sideways or inverted. But if the formula contains a strong solvent, such as acetone, methylene chloride or toluene, or if it displays a moderately high weight loss rate in the upright position, then inversion can easily cause the rate to increase anywhere from about 20 to 100%. Seepage rates almost always increase with increasing storage temperatures. As a very rough rule, when the storage temperature increases by 25°F (14°C), the rate of weight loss will increase by 50 to 100%. This generalization applies between 40° to 125°F (4 to 52°C). Many formulas with relatively large percentages of high solvent ingredients will function in a satisfactory fashion up to 100° or 110°F (38° to 43°C), above which they may eventually turn into latent leakers. The favored storage temperature for testing aerosol weight loss and compatibility is 100°F (38°C). This temperature will cover most field conditions and will promote a 50 to 100% acceleration of weight loss (over ambient temperatures found in the home). It will also act to speed up any corrosion or organoleptic problems, also by 50 to 100%, while still providing a valid qualitative relationship to room temperature effects. On the other hand, above 100°F )38°C), and particularly above 125°F (52°C), results may be obtained which would never occur at ordinary field temperatures. In one case, a water-based insecticide perforated a tinplate aerosol can in a week at 160°F (71°C), whereas packs stored at up to 100°F (38°C) showed almost no incompatibility, even after two years. Table II (pages 158, 159) shows the effect of temperature, gasket selection and other factors on weight loss, using a very high solvency formulation based on 62% methylene chloride. When latent leakage took place, it generally occurred within four to eight months. As a reference to the various crimp depths used in the table, it can be suggested that optimum dimensions would be those listed as follows on page 158.
158 The Aerosol Handbook GK-45 NVH gasket Water-based gaskets, as WDH 0.042 "Viton gaskets 0.050 " Buna and Neoprene gaskets 0.014 "PE-sleeve gasket 0.178 ±0.005" 0.185 ±0.005" 0.197 ±0.005" 0.205 ±0.005" 0.182 ±0.005" Data for Table II on Facing Page In this example depths were made on the low side of the specification or below it, recognizing the high solvent properties of the formulation. A considerable body of knowledge has been assembled which suggests that the leakage rate through the mounting cup gasket seal is only 10 to 20% of the permeation loss through the stem gasket. One way to determine the leakage route(s) through an aerosol dispenser is to carefully gas a du Pont Dytel-12 solution into the formulation via the valve stem. This solution consists of a brilliant red dye in P-12. Any concentration can be added to the can, within headspace limitations. The can is then inverted and allowed to remain for a while until a red stain shows on the exposed area of the stem gasket or on the skirt of the valve cup. This will serve to pinpoint the site of leakage. To determine the differential leakage rates between stem and cup gaskets a double eudiometer tube is used. This simple apparatus is shown in Figure 3. Pack r-l 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 No. Cans 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 24 24 24 24 24 24 36 24 12 12 48 36 36 Valve Seaq. Seaq. Seaq. Seaq. Grace Grace Summit Summit Summit PVC PVC PVC PVC Seaq. Summit Summit Summit Summit PVC Coster Grace Grace Summit Summit Summit Summit Summit Summit Summit Summit PVC PVC PVC PVC PVC Summit PVC Summit Summit Summit Summit Summit Summit Cup Gasket Cut buna Cut buna Cut buna Cut buna GK-45 GK-45 GK-45 GK-45 GK-45 PE Sl've PE Sl've PE Sl've PE Sl've Cut Viton Cut Viton Cut Viton Cut Viton Latex 1809 Latex WDH Stem Gasket (Blind) .050"buna .050"neop. . 042"Viton (Blind) (Blind) .050"buna .050"neop. . 042" Viton Buna 72 A Buna 72A Neoprene Neoprene (Blind) .050"buna 050"neop. 042" Viton .050" buna .050"neop. (Flowed In) Neoprene GK-45 GK-45 Cut Viton Cut Viton Cut Viton Cut buna Cut buna Cut buna 1/2 GK-45 GK-45 Latex WDH Latex WDH Cut buna Cut buna PE Sleeve Cut buna Latex WDH Cut Viton GK-45 GK-45 GK-45 GK-45 (Blind) (Blind) .050"buna .050"neop. Crimp Depth 0.190" 0.190" 0.190" 0.190" 0.175" 0.185" 0.175" 0.175" 0.175" 0.175" 0.185" 0.175" 0.185" 0.190" 0.190" 0.190" 0.190" 0.175" 0.175" 0.180" 0.185" 0.1G5" 0.185" 0.185" .042" Viton 0.185" .050"buna .050"neop. 0.185" 0.185" .042" Viton 0.185" 050"buna 0.165" 042" Viton 0.165" Viton Viton Viton Viton Viton Viton Viton Viton Viton Viton Viton Viton GK-45, low (Blind) lined on cud 0.165" 0.175" 0.190" 0.185" 0.175" 0.180" 0.167" 0.190" 0.175" 0.165" 0.170" 0.170" 0.170" Figure 3. Cross Sectional View, Showing Aerosol Valve with Stem Gasket and Cup Gasket Eudiometers
Aerosol Valves 159 Table II Weight Loss Data for a Non-Flammable Aerosol Insecticide Product (g/yr) (3% Oils, 3% Isopropanol, 62% Methylene Chloride and 30% Propellent Blend A46) Pack 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 Crimp Diam. 1.090" 1.090" 1.090" 1.090" 1.080" 1.070" 1.080" 1.080" 1.080" 1.080" 1.070" 1.080" 1.070" 1.090" 1.090" 1.090" 1.090" 1.080" 1.080" 1.070" 1.070" 1.080" 1.070" 1.070" 1.070" 1.070" 1.070" 1.070" 1.080" 1.080" 1.080" 1.080" 1.090" 1.080" 1.080" 1.080" 1.080" 1.090" 1.080" 1.080" 1.080" 1.080" 1.080" Weight Upright aver. 3.42 4.07 5.31 0.86 max. 4. 4, 11. 1. ,39 .62 14 53 Loss (77 °F/yr) Inverted aver. 3.62 6.51 6.66 1.64 max. 5. 12. 14. 2. 09 82 ,79 ,40 i 4, 4 4. 5. 4. 4. 5. 2. 5. 9. 5. Upi iver. .66 .39 10 05 14 00 86 ,81 ,13 ,64 ,15 10.38 1, .24 Weight Loss (100°F/yr) right max. 6. 6. 4. 9. 6. 6. 8. 3. 7. 32. 10. 44 06 59 04 54 ,28 73 03 ,28 ,24 ,94 33.80 1, .92 Inverted aver. 25.78 18.66 empty empty 30.68 21.92 26.98 34.38 18.65 29.99 2.30 21.25 15.67 6.50 23.84 16.00 0.91 empty 37.40 25.49 31.49 23.42 28.49 5.17 4.87 5.86 6.49 5.44 4.62 7.42 3.30 6.26 7.45 7.63 6.67 2.00 max. 26.35 19.34 empty empty 31.46 22.57 33.91 37.24 20.68 31.74 2.97 21.94 16.29 7.90 24.25 17.52 1.24 empty 39.00 26.93 32.35 23.96 30.25 6.85 7.22 6.82 8.65 6.30 4.86 17.27 3.82 10.34 8.00 20.01 10.37 4.00 Weight Loss (120°F/yr) Upright aver. max. empty empty 8. 10. 7. 7. 74. 1. ,76 ,41 .09 .91 28 93 10. 12. 9. 9. ,28 52 ,27 .48 empty 2. ,38 Inverted aver. max. 5.51 5.92 6.90 7.40 7.40 8.01 16.73 27.08 6.12 6.42 10.80 12.14 empty empty empty empty 9.59 14.39 13.49 15.59 8.95 10.60 8.45 8.81 16.77 46.87 2.75 5.05 No. 0 0 0 0 3 3 3 2 0 3 3 2 2 0 3 0 0 1 0 1 0 3 3 1 0 3 0 0 3 3 0 - 0 0 0 0 0 0 1 0 5 0 Gross Leakers % 0 0 0 0 100 100 100 67 0 100 100 67 67 0 100 0 0 33 0 33 0 100 100 33 0 100 0 0 100 100 0 - 0 0 0 0 0 0 8 0 18 0
160 The Aerosol Handbook Table III Typical Gasket Swell Levels After Immersion in Common Aerosol Solvents (Three days at 7T>F-25"C) Solvent n-Hexane Ethanol - Anhydrous Acetone Methylene Chloride Perchloroethylene Buna-N 1±2 1±4 32 ±14 57 ±22 9±8 Neoprene 4±2 0±2 7±4 35 ±5 32 ±4 Chlorobutyl 40 -1 2 23 47 Viton A 0 1±1 56 ±12 5±3 1±1 EPDM 26 -2 -3 ±3 9 32 ±5 Polysulfide 0 i 8±3 53 7 Polyurethane 4±2 13 ±8 35 ±7 40 10 Courtesy of the FEA (Draft X-641) Note: In five instances, out of 42, the figure or range denotes shrinkage. See interpretative limitations, as noted in text. A more complete explanation of eudiometry is provided in the current Seventh Edition of the CSAiA Aerosol Guide. In this instance, the twin tubes are pre- filled with water and are then placed over the valve pedestal and valve cup, respectively by holding the entire affair under water. After placement, the test unit is stored upright at ambient temperatures for two or three days, at which time the volumes of trapped propellent gas are noted. They may be calculated back into weight loss per year figures. Alternately, the weight loss of the dispenser can be determined over the testing period. If the can is assumed not to leak, or if it is a one- piece aluminum can, then the collected gas volume can be related to the weight loss, after which the stem gasket loss and the cup gasket loss can be determined readily. Using combinations of methods such as these it has been found that the majority of valve leakage occurs through the seal between the top of the stem gasket and the opposing part of the pedestal. The usual causes are gasket variations, along with varying degrees of gasket compression when the stake is made to lock the valve components within the pedestal. The valve shown in Figure 2 is the Model SV-73 Vertical Action Valve by Summit Packaging Systems, Inc. and it has castella- tions on the upper part of the valve body that come up against the top of the pedestal. This mating of plastic against metal leaves a rather fixed vertical dimension for the stem gasket, so that compression will then relate almost solely to variations in gasket thickness. This design is viewed as superior to that of some other valve configurations. It should be noted that stem gaskets are typically 0.042 ±0.005" (1.07 ±0.13 mm), which still leaves a lot of latitude for compressive variation, despite the fixed height of the gasket recess. The compatibility between gasket and product has a profound effect upon weight loss. Products affect gaskets in a variety of ways. One of the most obvious is swelling or (occasionally) shrinkage. There may also be leaching of certain additives, a breakdown of the polymeric structure and other degradative effects. Table III illustrates the short-term effect of five common solvents on seven elastomers, all of which have been used for either stem or cup gaskets at one time of another. A number of limiting comments must be made in relation to Table III. They are as follows: a. Variations in swell for a given gasket type may relate to toughness, additives, Shore A or Durometer hardness and batch variations. Table IV (Part 1 below, Part 2 on facing page) All cans were 211 x413 size; plain ETP inside. All Viton stem gaskets were 0.042 " (1.07 mm) thick. Packs 4-Ca and 4-Cb were designed to check weight losses at the upper and lower edge of the crimp depth specification of 0.170 ±0.005" (4.32 ±0.13 mm) of Pack 4-C. M packs contain methylene chloride; C packs contain 1,1,1 -trichloroethane. Pack 1-M 1-C 2-M 2-C 3-M 3-C 4-M 4-C 4-Cn 4-Cb No. Cans 60 36 24 3S 24 36 36 84 12 12 Valve PVC PVC PVC PVC PVC PVC Summit Summit Summit Summit Cup Gasket Latex WDH Latex WDH Cut buna Cut buna Cut Viton Cut Viton GK-45 GK-45 GK-45 GK-45 Stem Gasket Viton Viton Viton Viton Viton Viton Viton Viton Viton Viton Crimp Depth 0.165" 0.165" 0.190" 0.190" 0.190" 0.190" 0.170" 0.170" 0.1G5" 0.175"
Aerosol Valves 161 b. Swelling results will be different for other temperatures and time periods. If swelling is continuous with time, the gasket will eventually disintegrate. Some gaskets will swell for a few days and then shrink to well below the original size before reaching equilibrium. c. Gasket swelling in a mixture of two solvents cannot be predicted from a knowledge of the degree of swelling in each one, although it is generally within the range of values. Exceptions are found for mixtures containing the lower alcohols or water, where swelling may exceed the values for any single component. d. In about 90% of the tests the swell values at three days represented equilibrium states, but in some instances up to 21 to 28 days were required to reach equilibrium. In the case of neoprene stem gaskets used with a Choke and Carburetor Cleaner, the product was satisfactory at 28 days, but at between 36 to 48 days it started protruding out of the pedestal and causing gross leakage. e. Buna (nitron) sometimes shows a delayed frothing effect between gasket and stem due to very slow seepage. Although this may be unsightly, weight losses are small. The inclusion of very small amounts of methylene chloride has sometimes been made to correct formulations showing either shrinkage or no effect on gaskets. In general, it is desirable to have from about 2 to 9% of swell, but swells over 10% should be viewed with some concern. On the other hand, cup gaskets seem to be more "insulated" from swelling problems than are stem gaskets, simply because of the crimp, and the fact that the elastomer just above the crimp is inhibited from swelling because there is no room for expansion without dislodging the seal, all the way around the valve cup. A good, extra-tight crimp is vital for susceptible gaskets to perform well in high solvency systems. An example of this type of performance is given in Table IV, where several cup gaskets are compared with formulas that contain either 62% methylene chloride or 62% 1,1,1-trichloroethane but are otherwise identical. Viton stem gaskets were used since this material is known to give very low weight losses with chlorinated solvent formulations; see Figure 2, pack No. 25, and Figure 3, pack No. 3M and 3C. Although Viton gave the best results it is very expensive, commanding an up- charge of $5.00/M or more for stem gaskets and about $50.00/M for cut cup gaskets. It is not normally used if there are any alternates. (Butyl rubbers command similar premiums.) Table IV Comparisons of Weight Loss Between High Methylene Chloride and High 1,1,1-Trichloroethane Aerosol Insecticides (3% Oils, 5% Isopropanol, 62% Methylene Chloride or 1,1,1-Trichloroethane and 30% A46 Crimp Diam. 1.080" 1.080" 1.090" 1.090" 1.090" 1.090" 1.080" 1.080" 1,080" 1.080" Solvent CII2C12 CH3- CC13 CH2C12 C H3 * CCI3 CII2C12 CH3-CC13 CII2C12 CH3CCI3 CII3CCI3 CH3CCI3 Weight Loss Upright aver. max. 3.42 4.39 1.33 1.80 0.67 0.78 0.29 0.49 12.25 45.41 1.11 2.07 (77°F (g/y) Inverted aver. max. 3.62 1.35 0.77 0.33 4.18 0.99 5.09 2.38 0.92 0.45 4.98 2.49 Weight Loss Upright aver. max. 5.30 1.54 4.09 1.67 2.80 0.53 8.72 3.07 4.59 2.48 3.03 0.90 31.79 119.80 2.20 2.01 1.32 31.88 2.75 3.44 ; (100°F g/y) Inverted aver. max. 6.34 2.05 5.86 1.90 3.30 0.51 9.52 1.55 2.56 2.74 17.25 2.79 6.82 3.16 3.82 0.92 18.10 4.35 4.20 3.50 Weight Loss Upright aver. max. 8.76 10.28 2.91 3.55 83.31 empty 1.89 2.43 (120°Fg/y) Inverted aver. max. 9.59 14.40 13.23 64.77 47.69 63.55 1.85 2.53
162 The Aerosol Handbook Valve manufacturers recognize the importance of high quality gaskets to assure sealing integrity. One major supplier inspects 800 cups in every lot of 175,000 for gasket voids. This is a slug type defect, tending to begin suddenly and then die away rather quickly. At cup gasket thicknesses of below about 0.012 " (0.3 mm) they are unavoidable. Finding one defect is cause for rejection and reinspection of the lot. The GK-45 NVH thickness of 0.022 ±0.007" (0.56 ±0.18 mm) with an AQL of 1.5 has now been both altered and tightened up considerably by several large marketers and valve makers. The most recent thinking suggests 0.025 ± 0.007" (0.64 ±0.18 mm) with an AQL of 0.10. The maximum single part variation is now 0.010" (0.25 mm). The so-called sidewall gasket (section) is either the usual 0.175 ±0.015" (4.45 ±0.38 mm), AQL = Table V Nomenclature and Structure of Elastomers Used For Valve Gaskets Tradename Chemical Name Polymeric Structure Polyethylene, LDPE or PE-Sleeve (Various) Buna, Buna N, Perbunan-N, Nitrile or KP-6 Buna BunaS EPDM Buna CB or Isoprene Butyl rubber Neoprene, Perbunan-C or 759 Neoprene (Various) Chloro-butyl Viton Thiokol Vulkollen BunaP Polyethylene Polybutadiene Acrylonitrile-butadiene Styrene-butadiene Ethylene-propylene-butadiene (-Cri2~Cri2""Cri2""Cri2"")n (-CH2-CH =CH-CH2-)n [(-CH2-CH =CH-CH2)m-CH2-CH-]„ I CH2 [(-CH2-CH =CH-CH2)m-CH2-CH-]n I C6H5 [-CH2-CH2-(CH2-CH = CH-CH2-)m-CH2-CH-]n I CH3 Polyisoprene Isobutylene-isoprene Polychloroprene Acrylonitrile-chloroprene Isobutylene-chloroprene Difluoroethylene-Hexa- fluoropropylene Alkyl-polysulfide Ethylenglycol-apidic acid-napthalinediisocyanate polyester (Proprietary) (-CH2-C=CH-CH2-)n 1 CH3 [(-CH2-C=CH-CH2-)m 1 CH3 (-CH2-C=CH-CH2-)n 1 CI [(-CH2-C=CH-CH2-)m | 1 CI [(-CH2-C=CH-CH2-)m 1 1 CI [(-CF2-CH2-)m-CF-CF2 1 CF3 (-CH2-CH2-S-S-)n 1 1 s s (Variable) (Unknown) CH3 | -C-CH2-]n 1 CH3 -CH2-]„ | CN CH3 1 1 -C-CH2-]„ 1 1 CH3 "]n
Aerosol Valves 163 0.25 below the cup curl, or now sometimes 0.171 ± 0.015" (4.34 ± 0.38 mm) on the same basis. Stem Gasket The gasket surrounding the stem is possibly the most critical part of the valve assembly. It has to maintain a reasonable gas-tight seal even when flexed during operation of the dispenser. It also comes into contact with the product on all its surfaces, with the lower flat surface being in direct contact with the formula at all times. In the U.S.A. nearly all stem gaskets are made from either buna or neoprene. One major valve maker offers elastomers such as buna P, (slightly harder than regular buna N) according to the results of swell tests and other examinations. The composition of these gaskets is unknown. Viton stem gaskets are used to a vanishingly small extent because of price. Neoprene stem gaskets are almost always supplied as low durometer stock, with a Shore A Durometer specification of 70 ±5. This same material is used for neoprene type seat gaskets for female valves. The specification is also standard in Europe. For instance, Metal Box Limited supplies neoprene only as "Neoprene 70" for their Metal Box Precision valves and Metal Box CL and CLF valves. Buna N stem gaskets are available with Shore A Durometer specifications of 55 ±4, 65 ± 4, 68 ± 4, 70 ±5 and 75+5, and perhaps others as well. However, most valve manufacturers have standardized on only one, two or at the most three, for their valves. The higher durometer specifications are sometimes preferred for high pressure (CO2 type) formulations, as well as for high solvency compositions where their inherent toughness tends to inhibit swelling to some degree. Powder-containing products also work well with the higher range bunas. For example, a popular antiperspirant utilizes both 68 and 75 durometer material. Buna N stem gaskets are a popular item in Europe, where they are often called nitrile gaskets. They are available in the same durometer range. The selection of stem gasket durometer is often dictated by the design features of the aerosol valve. For example, one popular valve in the U.S.A. and Europe can handle stem gasket durometers of from 55 to 70 and can be ordered with any gasket specification in the range. Others may not have this latitude. Spring compression, valve body design and other factors influence gasket selection. Stem gaskets are made from other buna rubbers, from Viton, and sometimes from other elastomers. A greater diversity appears to be available outside the U.S.A. Table V provides a listing of some of the valve gasket materials that have been used, along with their polymeric structures. Again, it must be recognized that each elastomer category contains specific compositions that very widely in terms of additives, copolymer ratios, molecular weight distributions, degree of cross-linking and so forth. As an example of an obvious variation, both buna N and neoprene are available in white as well as black. The white modifications are used mostly in the case of glass colognes and perfumes, where the container is transparent. A number of years ago, it was discovered that traces of lampblack carbon from black buna ferrule mounting gaskets were getting into alcoholic products and discoloring them rather significantly. The problem was eliminated by replacing the carbon with titanium dioxide or zinc oxide, although with a minor loss of engineering properties. Stem gaskets are usually die cut from sheets or strips of material having a very smooth surface finish. The thickness is generally in the range of 0.040 to 0.050" (1.0 to 1.3 mm), with tolerances of from ± 6 to ±12%, depending upon the supplier. The inside diameter relates to the geometry of the valve stem and is generally in the 0.096 to 0.148" (2.44 to 3.76 mm) range, with tolerances of from about ± 3 to ± 4 %. The outside diameter also varies considerably with valve design but is often in the 0.375 " (9.5 mm) area. Not all gaskets are round. The Precision Valve Cor- opration has developed a unique "hex-gasket" with a hexagonal periphery for use with their spined cup & hex gasket very high speed T-t-V gassing valves. The mounting cup hole is ringed with six 0.040" (1.0 mm) round cut-outs, giving it a star-like appearance and facilitating extra-fast transfer of liquid propellent past the pedestal "barrier". Once inside the pedestal, the propellent can go past the depressed area of the stem gasket, between it and the valve stem, but also through six more-or-less chord-like apertures between the hex- gasket and the pedestal wall. The company recommends this valve for instantaneous T-t-V impact gassing and other applications, where extra-fast propellent injection can be beneficial. The valve can be either impact or liquistatically gassed at rates of from 0.5 to 1.5 seconds per unit, as a general rule.
164 The Aerosol Handbook Valve Stem The stem is a hallmark of the male type valves. For the female types, the stem is usually made a part of the sprayhead. In the early years of the aerosol industry, stems were always made of brass or bronze, first as little pins and then, after about 1951, as regular hollow tubes with expanded bases, much like those that exist today. The brass stem survived until about 1957. Nylon stems, meanwhile, came into existance about 1952. As they were improved and the industry gained confidence in them, they almost totally displaced the more costly brass stems by about 1955. The valve stem provides a metering orifice for the product, plus a channel to carry the material from the valve chamber into the actuator. It is either depressed or tilted sideways in order to operate the valve. The large foam-type valve stems or stalks made by the Clayton Corporation, Super-Whip Valve Manufacturing, Inc. and a few other firms do not require actuators. They dispense the product by a tilt-action principle from about an 0.125 " (3.2 mm) hole at the end. Most stems are made of engineering plastics such as nylons or acetal, but for special applications they have been made of polyester or polyolefin plastics. The orifice through the side of the valve stem is generally called the stem orifice or metering orifice. Using Laser beams, experimental stem orifices as small as 0.005 " (0.13 mm) have been made, but they are highly subject to clogging and other problems. Production capability has been established for 0.010" (0.25 mm) stem orifices as a practical minimum diameter. Single metering orifices as large as 0.050" (1.27 mm) are known, as in the Seaquist PF-70 series valves, but usually they are not used above 0.025 " to 0.030 " (0.64 to 0.76 mm). At that point, it is often convenient to use a two, three or four orifice stem. One of the larger multi-orifice stems is the 3 x 0.050 " (3 x 1.27 mm), but even larger sizes are being developed. The valve stems with very large orifices are statistically more trouble-prone than other types. The vertical travel distance is somewhat increased, gasket deformation into the larger holes has to be considered, and of course the stem will be weakened at the orifice area to some extent. Since people are used to both toggle-acting and vertical-acting valves, they sometimes try to operate the vertical types as if they were toggles. This is especially true for starches and certain other products, where a high percentage of each valve type is in use. If a 3 x 0.050" (3 x 1.27 mm) or similar stem is forcefully pressed at an angle, it may deform irreversibly at the orifice area or even crack. Valve manufacturers have developed various mounting cup features that help protect vertical acting valves against this type of unintentional customer abuse. One of the earliest was developed about 1957, when customers misused a certain valve and caused it to spurt a bug killer up from between the stem and stem gasket seal. The top of the pedestal had been flat and the stem hole was larger than it needed to be. A new mounting cup design was offered shortly afterward, where the area near the stem was flanged upward and hugged the protruding stem. In a few instances, the stem is also fitted with either an orifice or an orifice function at the top. For example, the Precision Valve Corporation 04-14 Series stem is equipped with a top metering slot of 0.011 xO.016" (0.280.41 mm) size. The slot is readily accessible for cleaning and is used for paints and similar products in conjunction with PVC's 21-46 Series "Delta" actuator. In a second example, PVC uses a special 04-86 Series stem with their 01-87xx Series buttons in order to get a mechanical break-up (M.B.U.) action from a one- piece actuator. The deeply chamferred top section fits precisely into the mating area of the actuator and acts with it to provide the needed swirling action. Some valve stems have a barb or molded-in lock ring around the periphery so that actuators, once attached to the stem, are almost impossible to pull off. For some products this can be an advantage. For example, in the case of highly lubricious products like silicone oils and penetrating oils, buttons might tend to pop off the stems after use, because of the momentary pressure still in the stem orifice and internal portion of the sprayhead. Many of these same product types sometimes act to swell the polyethylene or polypropylene buttons more than the nylon stem, exaggerating the problem. A few stems are molded with unusual internals, such as a 0.040 " (1.02 mm) chamber or a 0.030" (0.76 mm) post. These attributes lessen the volume inside the stem and reduce product afterspray and drool following shut- off at the stem metering orifice. Whenever a ring-and-pad foam spout, partial or full diameter spray dome or other fitment is to be attached to both the valve stem and the rim of the valve cup, the question of relative stem height becomes important. Stem height is defined as the vertical distance from the top of the stem to the top of the arch of the mounting cup, after the dispenser has been filled, gassed and hot-
Aerosol Valves 165 tanked. It is a function of the protruding length of the stem, known as stem extension, and the pedestal height relative to the top arch of the mounting cup. Stem heights are influenced by the cup contour (flat or conical), the stem extension and the method of production. When a valve is crimped under ordinary conditions the stem height rises approximately 0.040 " (1.0 mm). Adding pressure to the can causes a trace of upward pedestal distortion and stem gasket compression, totalling around 0.007" (0.18 mm); another 0.008" (0.20 mm) or so is added during hot-tanking. When the can cools back to ambient conditions, a relaxation of about 0.005 " (0.13 mm) takes place. The result of all these increments is an overall stem height increase of about 0.050" (1.3 mm) during production. Many valve suppliers offer valve stems in three or four lengths, plus the option of using either a flat or conical cup as a means of roughly matching the stem heights required by these special actuator fitments. The vertical difference between flat and conical cups is approximately 0.100" (2.54 mm), although this will vary with particular designs. In addition, the filler has the option of using "keepers" on his gassing equipment which act to limit the height of the pedestal and therefore the valve stem. With all these options, the filler can usually produce the desired stem height within about ±0.020" (0.5 mm). This is considered satisfactory. Stem height is checked during production using either a "go/no-go" stepped gauge block or a special dial micrometer. Keeper adjustments may have to be made occasionally, if the range starts to drift significantly. The suppliers of foam spouts, actuator domes and other fitments should always be asked to stipulate the required stem height specification in writing, so that appropriate valve cups and stems can be selected for the development program. Valve Body For a male, vertical-acting valve, the basic function of the valve body (sometimes called the housing or the spring cup) is to provide an enclosure for the spring to force the base of the stem up against the valve stem gasket. It may also be provided with a tailpiece orifice and perhaps a vapor-tap orifice, and serves to make a connection with the dip tube. Valve bodies are generally molded of the same plastics as stems, using large, multi-cavity injection machines. The tailpiece or main housing orifice extends from about 0.010 to 0.260 "(0.25 to 6.60 mm) in diameter. In special cases there is no orifice as such, but large slots or channels, as in the Seaquist Valve Company NS-29 aerosol valve assembly, designed for bag or piston type dispensers. The larger orifices are designed for viscous products. In many cases, the dip tube is inserted into the tailpiece entryway and may or may not preempt the need for a tailpiece orifice. In the Seaquist NS-24 capillary valve assembly, any of six different capillary dip tubes may be inserted. The entry is chamferred for highly reliable machine insertion, and a circular barb or molded-in locking ring makes it almost impossible for the dip tubes to be separated. The capillary tubes have i.d.s of from 0.018 to 0.060 " (0.46 to 1.52 mm) and can thus function as a lower or "tailpiece" orifice, if one is needed. Vapor-tap orifices are used commonly to add a small amount of vapor phase propellent to the liquid stream, which acts to give a finer break-up, a lower delivery rate and a warmer spray. As an example, many antiperspir- ants use vapor-taps in order to reduce spray rates without reducing the other orifice sizes and taking the risk of clogging the valve with the aluminum salt. Vapor-taps are bored through either the body wall or the shoulder area near the base. They are either molded in or drilled by Laser to sizes which range from 0.010 to 0.030" (0.25 to 0.76 mm). Holes down to 0.005" (0.13 mm) have been made by Laser equipment but clog easily and in tests with whipped creams and certain other products did not seem to provide any significant benefit. Vapor-tap holes of 0.008 " (0.20 mm) are probably available on a special order basis from some suppliers. On some occasions, a vapor tap orifice is used in the reverse sense to provide a suitable spray with the dispenser in the inverted position. In this case, the body orifice becomes the vapor tap orifice. Feminine hygiene sprays often apply this principle. It is desirable to have both the tailpiece and vapor tap orifices about the same size, or the spray upon inversion of the container will be either faster or slower than that in the upright position. Valve bodies have often been described as "regular" and "pressure-filling". In the past this meant that the regular valve was able to be gassed only at the rate propellent could pass through the valve stem and stem ori- fice(s), then through the body orifice(s) and into the can. If the valve stem orifice happened to be an 0.013 " (0.33 mm) size, even at extremely high propellent pressures approaching 1200 psig (8.27 MPa), it would still Next Page
Aerosol Valves Previous Page tanked. It is a function of the protruding length of the stem, known as stem extension, and the pedestal height relative to the top arch of the mounting cup. Stem heights are influenced by the cup contour (flat or conical), the stem extension and the method of production. When a valve is crimped under ordinary conditions the stem height rises approximately 0.040 " (1.0 mm). Adding pressure to the can causes a trace of upward pedestal distortion and stem gasket compression, totalling around 0.007" (0.18 mm); another 0.008" (0.20 mm) or so is added during hot-tanking. When the can cools back to ambient conditions, a relaxation of about 0.005 " (0.13 mm) takes place. The result of all these increments is an overall stem height increase of about 0.050" (1.3 mm) during production. Many valve suppliers offer valve stems in three or four lengths, plus the option of using either a flat or conical cup as a means of roughly matching the stem heights required by these special actuator fitments. The vertical difference between flat and conical cups is approximately 0.100" (2.54 mm), although this will vary with particular designs. In addition, the filler has the option of using "keepers" on his gassing equipment which act to limit the height of the pedestal and therefore the valve stem. With all these options, the filler can usually produce the desired stem height within about ±0.020" (0.5 mm). This is considered satisfactory. Stem height is checked during production using either a "go/no-go" stepped gauge block or a special dial micrometer. Keeper adjustments may have to be made occasionally, if the range starts to drift significantly. The suppliers of foam spouts, actuator domes and other fitments should always be asked to stipulate the required stem height specification in writing, so that appropriate valve cups and stems can be selected for the development program. Valve Body For a male, vertical-acting valve, the basic function of the valve body (sometimes called the housing or the spring cup) is to provide an enclosure for the spring to force the base of the stem up against the valve stem gasket. It may also be provided with a tailpiece orifice and perhaps a vapor-tap orifice, and serves to make a connection with the dip tube. Valve bodies are generally molded of the same plastics as stems, using large, multi-cavity injection machines. 165 The tailpiece or main housing orifice extends from about 0.010 to 0.260 "(0.25 to 6.60 mm) in diameter. In special cases there is no orifice as such, but large slots or channels, as in the Seaquist Valve Company NS-29 aerosol valve assembly, designed for bag or piston type dispensers. The larger orifices are designed for viscous products. In many cases, the dip tube is inserted into the tailpiece entryway and may or may not preempt the need for a tailpiece orifice. In the Seaquist NS-24 capillary valve assembly, any of six different capillary dip tubes may be inserted. The entry is chamferred for highly reliable machine insertion, and a circular barb or molded-in locking ring makes it almost impossible for the dip tubes to be separated. The capillary tubes have i.d.s of from 0.018 to 0.060 " (0.46 to 1.52 mm) and can thus function as a lower or "tailpiece" orifice, if one is needed. Vapor-tap orifices are used commonly to add a small amount of vapor phase propellent to the liquid stream, which acts to give a finer break-up, a lower delivery rate and a warmer spray. As an example, many antiperspir- ants use vapor-taps in order to reduce spray rates without reducing the other orifice sizes and taking the risk of clogging the valve with the aluminum salt. Vapor-taps are bored through either the body wall or the shoulder area near the base. They are either molded in or drilled by Laser to sizes which range from 0.010 to 0.030" (0.25 to 0.76 mm). Holes down to 0.005" (0.13 mm) have been made by Laser equipment but clog easily and in tests with whipped creams and certain other products did not seem to provide any significant benefit. Vapor-tap holes of 0.008 " (0.20 mm) are probably available on a special order basis from some suppliers. On some occasions, a vapor tap orifice is used in the reverse sense to provide a suitable spray with the dispenser in the inverted position. In this case, the body orifice becomes the vapor tap orifice. Feminine hygiene sprays often apply this principle. It is desirable to have both the tailpiece and vapor tap orifices about the same size, or the spray upon inversion of the container will be either faster or slower than that in the upright position. Valve bodies have often been described as "regular" and "pressure-filling". In the past this meant that the regular valve was able to be gassed only at the rate propellent could pass through the valve stem and stem ori- fice(s), then through the body orifice(s) and into the can. If the valve stem orifice happened to be an 0.013 " (0.33 mm) size, even at extremely high propellent pressures approaching 1200 psig (8.27 MPa), it would still
166 The Aerosol Handbook require many seconds to inject reasonable amounts of gas into cans. By a redesign of the valve body, the first pressure-filling valves were made (in the late 1950s) and these allowed the liquid propellent to flow into the valve body not only through the stem but around it as well, due to a rather profound displacement of the center portion of the stem gasket. Special buttons were developed for these valves. Some had tiny legs on the underside, so that they could not press hard up against the top of the pedestal and cut off die flow of propellent around the stem; others had one or two vertical holes to carry propellent into a cavity at the bottom of the button, and then down along the stem, while the skirt of the button (around the cavity) pressed against the pedestal. These pressure-filling valves worked very well unless there happened to be a tailpiece restriction. Depending upon valve design, the tailpiece is almost always an "orifice" of sorts, leading into the dip tube. The unrestricted tailpiece bores are usually 0.062 to 0.080 " (1.57 to 2.03 mm), and pressure-filling valves with such tailpieces can generally be gassed in less than one second. Difficulties arise, however, when the tailpiece contains a restricting orifice. Compared with an 0.080" (2.03 mm) tailpiece pressure-filling valve, one with a 0.025 " (0.63 mm) tailpiece will take 5.10 times as long to gas, and for a 0.013 " (0.33 mm) tailpiece the gassing period Figure 4. Model CL Valve Illustrated is the Model CL Valve by Metal Box Limited, England. Arrows indicate the propellent pathway through the CL Valve. A faster model CLF became commercial in 1981. An essentially identical valve is offered by the Precision Valve Corporation. The Seaquist Valve Company offers similar models in both vertical and toggle-acting variations. will be 22.9 times as long. Such problems can be solved by eliminating the tailpiece restriction, if practical, by gassing with a U-t-C machine, or by using a valve which can be gassed not only through the valve body but around it, as shown in Figure 4. As mentioned earlier, die splined cup and hex-gasket variety of valve pressure-fills by the usual routes through the body, but propellent also passes over the top of the stem gasket and then downward past the eight-tine stake via special body slits or castellations and into the head space. Gassing time is usually less than one second, regardless of body orifices. The new Metal Box CLF valve is said to be even 33% faster than their CL type. These valves probably will have somewhat less popularity in the U.S.A. and Canada because of the large numbers of U-t-C machines in use for moderate and high-speed production lines. However, the innovation should be well received in other parts of the world where T-t-V type gassing is very common. Spring The valve spring is one of the most reliable components of the aerosol package. It is made by winding the desired shape from wire of 0.016 to 0.035 " (0.41 to 0.89 mm) diameter on high speed springmaking equipment. The spring is then generally heat treated to regain strength. The individual springs are coiled in a close, then wider, then close lengthwise fashion to prevent interlocking during high speed valve manufacture. In the U.S.A., practically all springs are now made from Grade 302 stainless steel, typically passivated at 160°F (71°C) in a 30% solution of nitric acid, HN03, and then washed and dried. Probably the 0.020 " (0.51 mm) wire diameter is most common. In a few instances other stainless steel alloys have been required, such as Grade 316, containing 2% molybdenum, and which resists attack by mildly acidic sulfate solutions and several other media. This type is sometimes called for in pharmaceutical products for added insurance against possible incompatibility with the formulation. A few segments of the U.S.A. aerosol industry use hard drawn steel springs, and there is some interest in expanding this base, since the Grade 302 stainless springs are undoubtedly an overspecification for many anhydrous products. The savings would amount to about $0.50/M in 1982. Putting this into perspective,
Aerosol Valves 167 for a marketer with a sales volume of 100,000 aerosols per year, the cost reduction would amount to $50. This small benefit would have to be weighed against the cost of any confirming laboratory work, paperwork and the infinitesimally small risk involved in the change. Dip Tube While the primary function of the dip tube is to transfer the liquid product to the valve body, it may sometimes also serve as a metering station and as a repository of product for inverted spraying. There are three general classifications according to diameter. The smallest are called capillary tubes and have bores of from 0.013 to 0.060 " (0.33 to 1.52 mm), generally with an o.d. of 0.090 " (2.29 mm). Then there are the standard size tubes, generally having an i.d. of about 0.125 to 0.150 " (3.18 to 3.81 mm), which are probably used for over 75% of all U.S.A. aerosols. Finally, there are the macro-dip tubes, — sometimes sub-divided into large and jumbo sizes. The large size might include standard tubing of 0.165 and 0.194" (4.19 and 4.93 mm) i.d., whereas the jumbo tubes have i.d.s of typically 0.260 and 0.285 " (6.60 and 7.24 mm). Most generally, the macro-dip tubes are used to hold a significant amount of product so that the aerosol can be inverted and still spray for many seconds. For example, a jumbo dip tube with an i.d. of 0.285 " (7.24 mm) and an effective length of 8 " (203 mm) can hold about 8.4 ml of product. The standard dip tube is polyethylene, but high density polyethylene (HDPE) and polypropylene are used as well. Nylon has been used on rare occasions, sometimes for its clarity in clear glass aerosol products, and sometimes for its product resistance at unusually high temperatures. As an example, solutions containing corn oil (hot), turpentine and several other specific solvents cause polyethylenes to "melt" into a mush, but nylon is unaffected. At one time, polyethylenes were prone to stress-cracking after having been slipped over the tailpiece section of the valve body. This had the effect of creating a huge vapor-tap and rendered the finished aerosols almost useless. This problem has now been practically eliminated widi the development of suitable plasticizing agents, used at about 20% of the total plastic composition. Most suppliers cut the end of each dip tube with either a shallow notch or a slant configuration to prevent the remote possibility that it might jam directly against die bottom of the can and either partly or fully shut itself off. During gassing on a T-t-V basis, die dip tube tends to whip around and even one that will be cut on the short side can still form a shallow figure "S" and bind against the concave can bottom. Notched or slanted ends are good insurance in the case of aluminum monobloc cans or glass bottles. In the extrusion operation, the tubing is wound directly onto large drums, causing it to take a permanent curvature. The suppliers take advantage of this by orienting the curvature to the direction of the button or to a directional dot placed on the rim of the valve cup for the purpose of having die consumer line up the button widi the dot after purchase. This ensures diat the bottom of the dip tube is within the liquid product even though the can may be tilted during use. This feature is quite important for starch and sizing products as well as paints. In the case of personal deodorants and a few other products, the tube may be curved 180° away from the direction of the button or dot. This is because the can is often tilted backwards during actuation. About 1972, the U.S.A. aerosol industry agreed to designate the length of dip tubes according to the CSMA "A-D Dimension", which is the length from the top of the valve cup to the bottom of the dip tube, when it is held straight. Several valve suppliers provide customers with little plastic rulers designed to facilitate this measurement. Although the original proposal for standardizing dip tube length measurements originated with the F.E.A. in Europe, it is believed that die U.S.A. and Canada are the only countries diat have adopted it across the board. Like all plastics, dip tubes are affected by solvents. One of the most obvious effects is dimensional change. In almost every case, various degrees of swelling will result, aldiough with polypropylene and anhydrous ethanol uiere is a small amount of shrinkage. There may be odier examples of shrinkage, but they are rare. Like die elastomers, plastic dip tubes may reach an equilibrium state rather quickly, or may take months to do so. We have not been able to verify the widespread suggestion that about 90% of the swelling takes place in the first 24 hours of ambient storage. Table VI on page 168 shows the effect of 19 important aerosol solvents upon two different compositions of low-density poly- ediylene (LDPE) and polypropylene. The two polyethylenes behave quite differendy with certain solvents. The linear and diameter swelling levels bear only a general relationship to each other and
168 The Aerosol Handbook Table VI Dip Tube Swelling When in Contact with Solvents SOLVENT TUBING MATERIAL (Temperature - 75°For24°C) LINEAR SWELL (%) 1 Month 3 Months OUTSIDE DIAMETER SWELL (%) 1 Month 3 Months Acetone Methyl Ethyl Ketone Methyl Iso. butyl Ket. Methanol Ethanol (Anhydrous) Isopropanol Iso. butane LDPE LDPE PP LDPE LDPE PP LDPE LDPE PP LDPE LDPE PP LDPE LDPE PP LDPE LDPE PP LDPE LDPE PP Isopar H (Exxon) LDPE LDPE PP VM&P Naptha LDPE LDPE PP Kerosene (20% Arom.) LDPE LDPE PP H.A.N. (80% Arom.) LDPE LDPE PP LDPE LDPE PP LDPE LDPE PP P-ll (CCI3F) LDPE LDPE PP P-12 (CC12F2) LDPE LDPE PP Methylene Chloride LDPE LDPE PP 1,1,1-Trichloroethane LDPE • LDPE ■ PP Perchloroethylene LDPE ■ LDPE • PP Toluene Xylenes 0.0 1.8 1.8 0.9 1.8 0.9 0.9 3.6 1.8 0 0 0 0 0 9 0 0 9 2.7 3.6 5.4 3.6 5.3 0.0 5.4 8.9 6.3 2.7 5.4 0.9 4.5 7.1 3.6 5.4 7.1 4.5 5.4 7.1 6.3 P-114 (CC1F2* CC1F2) LDPE - 1 LDPE - 2 PP 1.8 5.4 4.6 4.5 7.1 5.4 8.0 8.0 6.3 0.9 1.8 1.8 0.0 1.8 1.8 1.8 1.8 0.9 0.9 3.6 1.8 0.0 0.9 0.0 0.0 0.9 -0.9 0.0 0.0 0.0 3.6 7.1 5.4 8.9 6.3 3.7 5.4 3.6 5.4 8.0 5 4 0 4 3 9 3 7, 2 3 3, 2, 5, 3, 4. 7, 5.4 8.0 8.0 7.1 0.9 1.8 3.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.7 0.0 3.4 2.9 3.0 3.9 1.6 0.7 6.2 3.9 5.2 3.9 1.9 1.5 4.5 2.9 3.7 6.2 3.6 3.7 6.2 3.6 3.7 2.3 2.9 6.0 2.3 0.6 2.2 2.8 1.9 3.0 5.1 3.6 5.2 8.5 5.8 5.9 1.1 0.7 1.5 1.1 0.3 0.7 1.1 0.3 1.5 2.3 0.6 1.5 0.0 0.0 0.0 0.0 5.7 2.6 6.7 3.9 5.2 3.9 3.2 3.7 0.6 3.6 6.0 2.8 3 0 4 9 0 1 6 2 8.5 6.1 5.9 1.1 0.7 1.5
Aerosol Valves 169 often not even that. The one month and three month results are often significantly different. In specific tests with a typical spray starch formulation, it was found that the swelling level seemed to be related to the 4% isobutane content, and not to the water and other ingredients, which had almost no effect. In one test, the maximum swelling appeared to occur after three days at 80°F (26.7°C) with a linear expansion of HDPE to 4.10%. After 31 days, the expansion was measured as 4.15 %. However, the same product showed a range of 3.50 to 4.24% (3.72% average) when stored at 80°F (26.7°C) for 7 days. When stored at 120°F (48.9°C) for 7 days the range was 3.62 to 6.01%, with an average swelling of 4.85%. These findings point out a few of the pitfalls involved in dip tube swell tests. Swelling of the dip tube may cause end-jamming (rare) and distortion, plus loosening of the connection to the valve body, if it fits over the tailpiece. In some cases, vapor may get into the liquid stream by aspiration, causing a slight vapor-tap effect. The usual procedure for avoiding these often minor consequences of swelling is to predetermine the amount of swell experimentally and allow for it in ordering the dip tube length. Precision, Seaquist and perhaps other valve companies are able to mold a peripheral barb on the outside of the tailpiece (Seaquist can also provide this on the inside), which is of great help in maintaining the connection between the dip tube and the valve body. Major marketers variously specify that both regular and capillary dip tubes must have a removal force in the 6 to 7 pound (2.72 to 3.18 kg) range. This measurement is most commonly made with a spring-loaded dial-type force gauge. Another method involves slipping the valve cup, upside down, into an inverted "T" slot of a standard weight, and then pulling up very slowly on the dip tube to see if it separates. Most non-barbed connections can pass the test, but barbed junctions pass it with great ease. In fact, the dip tube usually elongates and breaks before the connection is broken. Vertical Valve Assemblies Valves can be assembled at 800 to 1000 units per minute on some lines, but most of them are much slower than that. One manufacturer is now installing a ten-head machine capable of applying gaskets to valve cups at the rate of about 780,000 units per day. The larger valve makers have single plants that often produce in excess of 2 million valves per day and have nameplate ratings much higher than that. Many valve- making facilities produce their own injection molded bodies, stems, actuators, cups and other items, bringing them together for assembly in one section of the plant. In the U.S.A. the three largest manufacturers of vertical action valves are Precision Valve Corporation, Seaquist Valve Company and Summit Packaging Systems, Inc. The Precision Model 1-NN valve is said to come in over 10 million variations. It adapts to capillary, regular, macro and "no" dip tubes, simply by selecting the appropriate valve body. Their 32 standard stems divide into six series, each having a particular attribute, such as diameter, stepped profile, top metering slot, special sealing ring for suspension formulas and so forth. Within each series are stems having different height and/or orifice selections. Because of this design diversity, Precision valves can be used for almost every vertical action valve application. The Seaquist Valve Company has conveniently divided their very extensive line into eight series of basic assembly types: four series of vertical-acting valves, two of the toggle-action valves and two of their female-type valves. In addition, with their recent purchase of certain assets from the Ethyl Corporation (ARC Division) to manufacture various series of aerosol can valves, the above product line will be expanded to include the AR series female-type valve, as well as various overcaps and accessories. A listing of the eight series and their individual valve assemblies is given in Table VII on Page 172. The Summit Packaging Systems, Inc. firm also has a very extensive line of valve variables. They have elected to divide it into three basic constructions: their S-63 tilt- action valve, their S-73 vertical-acting unit and their CA-78 female-type valve. Each has its own retinue of components; for example, the S-73 has 11 stems covering two stem orifice height designs, and 36 bodies in two designs: the Series 23 for standard dip tubes and the Series 43 for capillary dip tubes. While these three major suppliers have selected very different ways to organize and present their elaborate lines of aerosol valves and accessories, their catalogs are superb sources of information for the aerosol development man and should be kept readily available. In addition to product listings, these books also include a lot of very useful technical information: newsletters, reprints of magazine articles and specific valve recommendations for various aerosol formulation types, to name a few.
170 The Aerosol Handbook MOLDED IN LOCK RING FLOWED-IN GASKET MOUNTING CUP Figure 5. Seaquist NS-31 Aerosol Valve Assembly Some valve makers illustrate specific valves with pictorial cross-sectional views, as shown for the popular Seaquist NS-31 valve in Figure 5. All valve makers provide easy-to-understand drawings of how their valves operate, as illustrated for the Precision Model 1-NN valve in Figure 8. In some instances, information is presented on various means of gassing the valve, showing the propellent pathways through and/or around specific models during production injection operations. For the specifications writer, the quality assurance person, engineers and others, all the valve manufacturers are able to supply detailed engineering drawings of their various components and finished assemblies upon request, as well as to provide answers to nearly all inquiries. FLOWED IN GASKET MOUNTING CUP Figure 6. Seaquist PF-71 Toggle Valve Assembly cm Figure 7. S-63 Tilt Valve by Summit Packaging Systems The Toggle Action Aerosol Valve At least two U.S.A. manufacturers make what is commonly termed a toggle action or tilt action valve as differentiated from die vertical action or reciprocating varieties. These are the Seaquist Valve Company and Summit Packaging Systems, Inc. In addition, the long- stem valves made by the Clayton Corporation and the Super-Whip Valve Manufacturing Company for foam products technically fit into this general category. As a rough estimate, toggle action valves of the sprayhead type probably account for 10 to 15% of the U.S.A. aerosol volume. They have excellent direction- ally characteristics, a factor which appears to be quite important to consumers. In addition, they have a very light and comfortable actuating force that is not available with the reciprocating or vertical action valves. In the vertical types, die consumer must press down with from 3 to 6 pounds (1.4 to 2.7 kg) of direct downward force to counteract the spring pressure plus the propellent pressure in the dispenser. In fact, for CO2 packs and other higher pressure packs, the actuating force may reach over 8 pounds (3.6 kg). In the toggle action valves, the consumer employs a sideways force to depress the seat and spring at one side until the seal between seat and stem gasket is opened and product flow can occur. The theoretical mechanical advantage is in the order of five to ten, offset by gasket compression and some other factors, but this means that the valve is very easy to operate, even for long periods of time. A typical toggle valve is illustrated as the Seaquist Valve Company's PF-71 Aerosol Valve Assembly; Figure 6. This may be compared with the Summit
Aerosol Valves 171 Packaging Systems, Inc. S-63 tilt valve, shown in Figure 7. Both the Seaquist PF-70 series valves and the Summit S-63 valvess are designed for very fast pressure filling, regardless of any body restrictions. The high rate of fill is possible because the propellent passes around the body and into the head space, with only an incidental amount traveling through the body. This feature helps to minimize "dip tube whip", which sometimes acts to bind the dip tube against the concave can bottom at a point inconsistant with the button orientation. By gassing with the button on, tipping and possible hand orientation operations by the filler are avoided. In order to gas with buttons on, the actuator should be made smaller in diameter than the valve pedestal. This prevents "hang up" of the button in the case of adapters designed to seal around the periphery of the pedestal by the mechanical compression of an "0"-ring. Where a slightly wider diameter button is required for some reason, the valve can still be gassed with the buttons on, but in this case the adapter will require a rubber boot that is designed to seal against the floor of the mounting cup. Much more gas loss will occur in this arrangement when the gassing head lifts off the container. For gassing purposes, the button and valve stem can be depressed vertically by the liquistatic pressure of the propellent, but better weight control and less gas loss will occur if the adapter is designed to make the seal, mechanically depress the button (allowing the valve to gas), release the button and then break the seal. Proper design of adapters is a major factor in good gassing operations, and many of those now available are known to have design features that can be improved significantly. Toggle action valves are useful with a wide range of products, and are particularly desirable where misdirection of the spray is a problem to be particularly avoided. In the case of an underarm product, misdirection could cause a consumer to spray the face or eyes. In the special case of high-solvency products, such as those Figure 8. Diagrams Showing Valve Action in Open and Closed Positions or toweefi/re/ire 4hb 4* /*t/rroM /i P£rg£**£ff 4^4/ivtr trf/Hir r<v</w, &->fX£r rt.£xe*, £-xpo*i*/ar *r£M &*/*/£.£ ro /vree/v4L Pg£**i/g£, T*£4/0r 4LJ.0IVIN4 coxaeH re* r£ 4vp {./gi/ie rtgptu- 4mt mis rs *e r?e6£B rMieu 0r/r/<?£- //V Mi.y£ *r£M 4MB f/H4Lty^7yfW9srrc>H — !4lLI/£ CLOtsc — -fat-ye &P£H££> - Courtesy Precision Valve Corporation
172 The Aerosol Handbook Table VII Compilation of Seaquist Valve Company Valve Series and Basic Assemblies NS-20 Series NS-21 NS-24 NS-26 NS-28 NS-29 NS-30 Series NS-31 NS-34 NS-36 NS-38 NS-39 NS-40 Series NS-41 NS-44 NS-46 NS-48 NS-49 ST-70 Series ST-71 ST-74 ST-78 St-79 PF-30 Series PF-31 PF-34 PF-40 Series PF-41 PF-44 PF-70 Series PF-71 PF-74 PF-78 PF-79 SF-80 Series SF-81 SF-84 AR Series AR-71 AR-74 0.158 " stem diameter, for interchangeability with overcaps and spouts. Standard dip tube Capillary dip tube Spray Anyway (Sprays upright or inverted) Jumbo dip tube Double slot body (Tubeless, for bag-in-can or piston can uses) 0.125" stem diameter, most popular, widest diversity of stems & actuators. Standard dip tube Capillary dip tube Spray Anyway Jumbo dip tube Double slot body 0.125" stem diameter, self-cleaning seal, especially good for powders. Standard dip tube Capillary dip tube Spray Anyway Jumbo dip tube Double slot body Toggle action, good directionality, positive shut-off & high sealing force. Standard dip tube Capillary dip tube Jumbo dip tube 0.107" (Tubeless) (For bag-in-can or piston can uses) Like the NS-30, but body moves to allow very rapid pressure filling, both through and around the assembly. Standard dip tube Capillary dip tube Like the NS-40, but body moves to allow very rapid pressure filling, both through and around assembly. Self cleaning seal for powders. Standard dip tube Capillary dip tube Toggle action, like the ST-70, but body moves to allow very rapid pressure filling both through and around assembly. Standard dip tube Capillary dip tube Jumbo dip tube 0.107 " (Tubeless) (For bag-in-can or piston can uses) Female valve assembly. Accepts only the 0.125" nominal stem. Fast gassing. Standard dip tube Capillary dip tube Female valve assembly. Accepts the 0.135 " nominal stem. Fast gassing. Standard dip tube Capillary dip tube Note: The KN series vertical-acting valve and PARC powder valve, acquired from Ethyl Corporation in 1981 are no longer available. with large percentages of methylene chloride or toluene, toggle action valves may give problems of weight loss or actuation due to stem gasket swelling and other effects. If toggle action valves are considered for such formulations, they should be checked most carefully for compatibility, and the valve manufacturer consulted for technical advice and assistance. The Clayton and Super-Whip valves are used almost exclusively on whipped cream products. Some years ago they were also used on shaving creams. However, foam spouts were developed that covered the entire mounting cup, and did not require can inversion to operate. These spouts provided a total valve system that was less expensive than the "stalk-type" valves, which were gradually displaced. In fact, two manufacturers of this type valve have closed and another has added a line of tilt-action valves. Avoset Food Corporation (Oakland, CA) provides an interesting, stemless type valve for whipped cream products—many of which they fill, for themselves and others—which is particularly adaptable to sterile filling applications. Their Model 201SS valve has a lever actuator as one option, a stainless steel body and a mounting cup with a proprietary flowed-in gasket. The stem sealing gasket is held tightly against the stem hole in the cup by means of a stainless steel leaf spring fitted into the cup at both ends, because of a special folded contour at the periphery of the cup base. The various actuators carry a dispensing pin designed to depress the leaf spring to allow the seal to part and the product to emerge. The valve does not use a dip tube and is operated with the container inverted. The technology of the mounting cups, elastomers, dip tube, spring and certain other parts of the toggle action valves was discussed under the heading of vertical acting valves. The Female Aerosol Valve The female valve design has been an important factor in the aerosol industry for over 30 years. It is made in the U.S.A. by at least three major valve suppliers: Newman-Green, Inc., Seaquist Valve Company and Summit Packaging Systems, Inc. It is characterized by having the valve stem contiguous with and an integral part of the actuator. The mounting cup thus has a hole in the center, leading down into a gasket-lined cavity with the valve seat at the bottom. The stem is inserted into this hole and then depressed vertically to actuate the valve. An expanded view of the components used
Aerosol Valves 173 for such valves is illustrated for the Summit CA-78 Female Valve, shown in Figure 9. The female valve is a well-designed efficient valve, eminently suitable for a number of specific applications such as dispensing paints and coatings. It is normally gassed by T-t-V methods with the buttons off, or by U-t-C with the buttons on. T-t-V gassing is extremely high speed, due to the absence of a stem orifice restriction and the usual absence of any tailpiece orifice. Most tailpieces are from 0.060 to 0.093 " (1.52 to 2.36 mm) in internal diameter, although this might be reduced by an inserted dip tube in the case of the Newman-Green Model R, R-34 and V-8 series. A significant exception is found in some bodies manufactured by Summit, which include ten Series 65 models with tailpiece restrictions in the 0.013 to 0.030" (0.33 to 0.76 mm) range, some of them also having vapor tap features. Summit also features six bodies with the full 0.060" (1.52 mm) tailpiece, with vapor taps ranging from none to 0.032 " (0.81 mm) diameters. The mounting cup of most female valves has what is known as a roll-over feature at the orifice to reduce or eliminate possible problems during die tipping operation. The metal around the cup orifice is simply rolled upward and then laid back, so that if the delicate end of the actuator stem is not perfectly centered over the hole, it will have a better chance of sliding sideways a bit and then entering normally. In the past, fracture of the stem has been a problem with tipped actuators. In some cases, the fracture was buried in the valve assembly and could not be detected on the production line, letting a defective product get out on the market. In others, an unusual slant to the actuator or some other feature would alert production control people to the problem. With modern refinements in tipping and valve cup design, plus the fact that a large number of female valves are U-t-C gassed, this problem has largely gone away. Female valve makers offer from two to four stem gasket i.d.s to accommodate the valve to products having different elastomeric swell properties. For example, the Newman-Green Model R Series valves have gasket i.d.sof0.118,0.123, 0.128and0.132"(0.30, 0.31, 0.33 and 0.34 mm). Most products can use the two smaller i.d. gaskets. Their gaskets are available in either neo- prene or buna-N, each in 70 Durometer. When filling formulas capable of elastomeric swelling into containers then sealed with female valves, care should be taken to <gS\ ACTUATOR Available in 4 styles with 3 GROOVE dimensions Flow Rate controlled by groove dimension MOUNTING CUP With ROLLOVER FEATURE FOR EASE IN TIPPING CASKET (INTERNAL') BUNA N OR NEOPRENE -SEAT -SPRING Stainless Steel -BODY Available in STANDARD or CAPILLARY with VARIOUS V.T. DIAMETERS -DIP TUBE STANDARD OR CAPILLARY Figure 9. Exploded View of CA-78 Female Aerosol Valve Offered by Summit Packaging Systems, Inc.
174 The Aerosol Handbook insert the sprayhead without delay. In one example, for instance, a carburetor and choke cleaner with a high level of xylene caused such a gross expansion of the gasket, that after a short while the sprayheads could no longer be reliably inserted. Since the terminal orifice system and the metering slots are both incorporated into the same component, fillers can often inventory just one basic valve and expect to use it for a wide range of applications. For example, Newman-Green provides about 104 spray- heads for their various valves and most are perfectly interchangeable from one basic type to another. Female valves are particularly desirable for paints, coatings and other products that may tend to dry out in the valve between uses. For other valve styles this might result in clogging, and this can, of course, occur also with the female types. But here the sprayhead can be removed from the rest of the valve and cleaned (sometimes by a brief immersion in lacquer thinner or some other strong solvent), then replaced in order to restore the valve to full operating status. Clogging problems may be reduced by actuator designs, and by means of repeated instructions to the user of paint and coatings products to briefly actuate the dispenser inverted, at the end of spraying, to allow the propellent to help clean concentrate out of the stem and orifices. A typical female valve assembly is illustrated in Figure 10, showing the Seaquist SF-91 unit. This valve accepts virtually any sprayhead having a 0.135 " (3.43 mm) stem diameter. A companion valve, the Seaquist SF-81, will accept 0.125 " (3.18 mm) stem diameters. This allows the Seaquist line of female valves and related actuators to be DIP TUBE Figure 10. Seaquist SF-91 Female Valve Assembly used interchangeably with conjugate components from other suppliers and also provides for the reverse situation. Sprayheads for female aerosol valves include both one-piece and two piece models. Some spray out horizontally and others spray upward at 10° or other angles, mainly to avoid the possibility of some slight spray impingement on the rim of the valve cup. The single-piece types have both forward and reversed internal tapers, as well as straight bore orifices, both for spraying and for use with extension tubes. The two- piece sprayheads may be of the mechanical break-up (M.B.U.) type or the non-mechanical break-up type. The Newman-Green Model 166 Series sprayheads are designed to be used with their V-8 Series valve assemblies to produce variable sprays, according to how the button is turned on the seat. Wafer collars of white plastic are available to be oriented and then pressed in place snugly on the valve just below the attached button. They are inscribed with lettering such as, "L—H - Adjust Spray", "L—M—H - Adjust Spray" and "Stream — Spray", and are used for specific mating variable sprayheads and assemblies. For example, one combination will give sprays having a low, medium or high delivery rate, by turning the button to the indicating point on the plastic wafer insert. A fan type spray is sometimes desired for paints and coatings. Newman-Green has these available in regular size sprayheads with slightly protruding inserts, as well as in a large button size where the o.d. is about 0.92 " (23 mm). The large size button, skirted to fill the one- inch (25.4 mm) valve cup, is also available in two-piece Model 181 and 186 Series in at least 38 spray variables. Ferrule Type Aerosol Valves During 1982 approximately 40 million glass and plastic-coated glass aerosol units were produced in the U.S.A., and all of them required a ferrule type valve. In addition, at least an equal number of 13 mm and 20 mm aluminum tubes were sold. These also required a ferrule type valve. A much more limited number of straight plastic aerosols were marketed, perhaps a few million, and the valves for these units were often integrated into the plastic top-and-body section. Otherwise, they required a ferrule type valve. Out of this background, the current domestic market for ferrule valves would appear to be in the area of 80 to 100 million units per year, or about a 4% share of the total aerosol business.
Aerosol Valves 175 These valves are made by the Risdon Manufacturing Company, Emson Research, Inc. and possibly one other U.S.A. firm on a special order basis. Thus the number of manufacturers is strongly down from the seven or so of about ten years ago, as a reflection mainly of the sales decrease in the glass toiletries area. Ferrule type aerosol valves are made for container finishes of 13, 15, 18, 20 and 32 mm sizes. The ferrule is almost always formed of aluminum and is usually supplied with a gold anodized finish. It replaces the mounting cup of the usual valve, and is attached to the container by a clinching operation, whereby the skirt is tucked under the finish using (generally) a direct inward squeezing operation or (uncommonly) an inward rolling operation. In the first process, a collet with about 16 to 20 tines is placed over the ferrule skirt at a predetermined height. A plunger or mandrel then descends, pinching the ends of the individual tines toward each other, so that they force the skirt of the ferrule inward. If the dimensions are correct, the ferrule, while being pressed inward, will pull downward with considerable force; the top becoming somewhat rounded in the process, but compressing the buna valve gasket very tightly between the top of the container and the flat rim of the ferrule, thus effecting an hermetic seal. The process can be likened to the attachment of caps on beer and beverage bottles. Because of their diminutive size product uses, valves for bottles and tubes usually have stem orifices in the order of 0.013" (0.33 mm), so that delivery rates will tend to be less than 0.5 g/s at ambient temperatures. The dip tube is normally an inside fitting capillary type; an i.d. of 0.045 "(1.14 mm) is the most common one in current use. Other i.d.s are available, down to 0.013" (0.33 mm) in polyethylene. Polypropylene is the most widely used capillary dip tube material, but polyethylene and even nylon may be obtained on special order. In addition to the standard valves there are also metered valves—sometimes called a meter-spray type. They are designed to dispense a fixed volume of product at each actuation. The dosages available from stock include 40, 50, 67, 80, 100, 150 and 250 mcl (microliters); others may be available on special order, depending upon sales volume. Most metered valves are pressure fillable. The majority of metered valves operate in the following fashion: when the actuator is depressed, a seal is produced between the metering chamber and the contents of the container. Further depression then opens the metering chamber to the atmosphere via the stem orifice and button. When the actuator is released, the connection of the chamber to the atmosphere is first broken, after which the chamber is connected to the contents via the dip tube. The pressure of the contents is always a combination of propellent and air partial pressures, whereas any liquid entering the metering chamber will only have the pressure of the propellent, plus that of a fraction of the total air, which is dissolved. The pressure differential between all of the air and part of the air is sufficient to cause the product to flow into the chamber and refill it completely. Then also, the warmth of the hand upon the aerosol unit will also cause a bit of extra pressure. The vast majority of metered valves deliver extremely small dosages, suitable for perfumes, certain pharmaceuticals and drug products. From time to time, valves such as the Risdon Magna-metering type and the Swallowfield macro-metering attachment have appeared and are capable of providing dosages of several grams. In one instance, valves were produced where the plastic metering chamber was about 0.95 " in diameter by 3 " long (24 x 76 mm), and it delivered just about 1.00 fl. oz. (29.57 ml) of product per shot. Such valves are rarely called for but might be available from existing molds and parts on a special order basis. The earlier metered valves could only be cold-filled, but all the present versions can be pressure loaded by passing propellent into the metering chamber and then out of it into the main content area by means of the liquistatic force of the material, which temporarily opens up an annular rubber seal around the housing, allowing the incoming propellent to by-pass the closed dip tube. Actuators for ferrule type valves take a number of forms, but most are simple polyolefin cylinders or truncated cones, with a plastic or metallic disc-type insert forming the terminal orifice. Upon occasion the plastic button may be friction fitted into a deep drawn anodized aluminum cup, to give the actuator the elegence of a metallic lustre or shine. Standard and metered valves available from Emson Research, Inc. are illustrated in Figure 11 on Page 176. These valves are available from Emson Research, Inc. in Bridgeport, CT, or from their facilities at Bredon, Tewkesbury, Glos. in England. Metered valves for bronchodilator uses are often marketed in conjunction with a large tunnel-like accessory that fits over the spray unit at one end. By depress-
176 The Aerosol Handbook ing a pad at one end of this 2 or 3 " (51 to 76 mm) long device, the correct amount of medication is caused to float into the tunnel, from which it can be inhaled by the user. Many years ago in Europe a meterspray inhalation product was introduced, which consisted of a dilute solution of acetylsalicylic acid (Aspirin active ingredient) and was said to work by rapid absorption into the bloodstream. Extremely low amounts were enough to cure headaches and even migraine attacks, because it could go directly to the seat of the problem with a minimum of dilution and loss. Relief was obtained in a few minutes or less. The product was withdrawn from the market for unknown reasons, but it does point to one more interesting and novel application of the aerosol principle. Special Components or Accessories The ingenuity of valve manufacturers and other people in the industry has acted to produce a large number of special purpose components and valve accessories that have increased the scope of aerosol systems. A few are now discussed. One-Shot Valves Possibly as much as 1% of the U.S.A. industry relates to products that utilize the entire contents of the can at one time. Individual cans ranging from 2.5 to 7.5 Av. oz. (71 to 213 g) of product are used, for instance, in the indoor insecticide fogger to thoroughly treat a room, or even a small house, ridding it of both crawling and flying insect infestations. A means of latching or locking the valve in an open position had to be found. At first a toggle action valve was used, with a special actuator that operated by pulling the stem sideways to the extent that the other end of the fitment could be latched around the cut edge of the valve cup. The valve was then able to spray the entire can almost vertically into the air and the particle size of the dispensed product allowed it to remain airborne for a considerable time. This device, while generally serviceable, has now been replaced with at least two other actuators. In one case, a special fitment was produced by the Precision Valve Corporation which locks into the crimping indentations and contains a hinged central pad with a short tube extending over the stem. A small orifice points directly up, over the stem connection. The unit can be sprayed as an ordinary flying insect killer (FIK) by lightly depressing the hinged actuator pad. But if the pad is depressed more fully, it has a lug that can be latched under the surrounding ring, causing the valve to spray continuously. If necessary, the pad can be disengaged by pulling it strongly upward. A second, quite different approach has been conceived by the Seaquist Valve Company. In this case a 202-diameter (52 mm) overcap is used, with a special depression molded into the center of the top surface. Figure 11. Standard and Metering Ferrule Type Aerosol Valves By the Emson Research, Inc. S13,15,18,20, or 32 mm valve NO. PART MATERIAL 1 2 3 4 5 6 7 Mounting Ferrule Body Stem Stem Gasket Spring Dip Tube Aluminum (anodized)* High Density Polyethylene Delrin/Celcon Buna* Stainless Steel (SS302)* Polypropylene capillary .045" I.D.* Valve Gasket Buna* *Others available on request MP 13, 15, 18,20, or 32 mm valve*** NO. PART MATERIAL 1 Mounting Ferrule 2 Body* 3 Stem 4 Stem Gasket 5 Spring 6 Dip Tube 7 Valve Gasket Aluminum (anodized)* High Density Polyethylene Delrin/Celcon Buna* Stainless Steel (SS302)* polypropylene capillary .045" I.D.* Buna* ♦Others available on request **Dosage available: 40, 50, 67, 80, 100, 150,250mcl. ***Pressure tillable
Aerosol Valves 177 When the overcap is removed and inverted over the valve stem, the depression area fits exactly over the valve cup rim and snaps onto it with peripheral lugs. When this is done, the valve stem is caused to slip into a shallow tube ending in a vertical orifice, and the stem is at the same time depressed so that it actuates. Admittedly the arrangement looks a bit unusual, but it functions very well indeed. It also saves the price of the special actuator by combining it into the overcap. This single product provides almost the entire market for the one-shot valve. Others may come along, such as fumigants and perhaps certain fire extinguishers, but that is where we are at this time in 1982. The VariSeal Aerosol Actuator The Essex Chemical Corporation (Mahwah, NJ) has established a VariSeal Group responsible for the marketing of a rather unique variable spray actuator. This device consists of a sprayhead designed to fit on either 0.125 or 0.158" (3.18 or 4.01 mm) diameter valve stems. It uses a dial to control the spray pattern. The dial fits on a lock nut and extends horiontally from the side of the actuator, just behind the spray orifice. By rotating the dial to the left and thus backing an internal sealing pin out from behind the orifice, the operation is converted from an off position to a fine spray, a medium spray, a coarse spray and finally a stream, during one revolution. The orifice sizes are 0.010, 0.013 and 0.015" (0.25, 0.33 and 0.38 mm). The invention is patented. Samples can be obtained by writing to the company. The device is illustrated in Figure 13. part section through the valve In the Closed Position. ' Showing "Spline" above the . mounting cup aperture ' Showing gasket nesting into the stem waist PROPELIXNT Pert section through the valve in its fully open pro- . pellent charging position. 1. Spline ndw located within [Jl >V the.mounting cup aperture, t, 1 \ \ the gasket is folded down \? V^-J V and the propellent is \ \ !'■ forced over the gasket \^- Figure 12. CLF Valve by Metal Box Ltd Detailed section of the CLF Valve by Metal Box Ltd, England, showing both the closed and open positions of the valve. OFF SPRAY The Aquasol and Aquamist Systems The "Aquasol" dispensing system was introduced by the Precision Valve Corporation in 1974, and a similar system known as the ' 'Aquamist" was developed by the Seaquist Valve Company the following year. It has been recognized that the total dispersive effect of propellents is never truly used in the aerosol systems. The poorest efficiency is developed with the regular solution system using a straight bore valve orifice. This same solution will provide a finer spray if the sprayhead is converted to a mechanical break-up (M.B.U.) type, and the spray will be finer yet if a vapor-tap valve orifice is added. These sophistications cause the propellent to work harder to produce a spray of greater and greater break-up. The Aquasol and Aquamist valves carry this one step further. They provide maximum break-up with minimum propellent. As the names imply, they STREAM Nf^, f=33==* s* -*■> Full Turn Left -iT ( 420 \u fj ) R> 505 MAX -. Figure 13. Variable Aerosol Actuator Operation The illustrations are for the Variseal "Dial-A-Spray" series
178 The Aerosol Handbook allow the use of water containing formulas, which are always hard to break-up into a finely divided spray pattern. A typical suggestion has involved hydroalcoholic deodorants with 6% active solution, 32% water, 32% ethanol and 30% hydrocarbon propellent. Hair sprays of equivalent composition have been suggested. All these products must be shaken before use, since they exist as two liquid phases. In the meanwhile, aerosol chemists have found that these valve innovations are often successful in producing fine, non-aqueous product sprays with less propellent than before. The valve of the Aquasol system is a significantly modified vapor-tap, vertical-acting type, where a product stream and a gas stream are caused to enter a valve stem with two vertical passageways leading into a special sprayhead. Separations prevent the gas and product from mixing until they reach a swirl chamber just behind the button insert. At this point they come together at high speeds and mix into what is probably a low density fluid containing millions of tiny gas bubbles •(^-ACTUATOR CHANNEL AQUASOL ACTION COMPONENT PROPELLANT INLET (VAPOR) PRODUCT ORIFICE DIP TUBE PRODUCT Figure 14. Aquasol Dispenser Stem and Sprayhead Aquasol is a Tradename of Precision Valve Corporation. of propellent per ml. The degree of mixing is far more efficient than that produced by ordinary vapor-tap designs. An illustration of the upper portion of the stem and of the valve sprayhead is provided in Figure 14. The Aquamist system is similar. Both provide a fine, dry spray with many existing water or solvent-based formulations. By modifying the orifices spray, rates can be adjusted to various levels within a range of 0.2 to 1.2 g/s. Millions of both valve systems have been sold, and the price is now roughly comparable with the cost of regular vapor-tap valves with M.B.U. sprayheads. Special Applicators A large variety of special applicators are available for specific uses. Oral applicators for inhalation therapy have been mentioned. Contraceptive foam applicators are also a small but important area. Dental applicators of stainless steel are used to administer anesthetics to gums to deaden the dermal tissues prior to injections. Simple plastic extension tubes are used for lubricants, anhydrous cleaning sprays and silicones — even for woodworms, in the case of one aerosol product. A product called "Prist'' is marketed by PPG Industries, Inc. to provide for the addition of methyl cello- solve to the fuel tanks of certain jet aircraft, at the same time they are being refilled. The material cosolves any small amounts of water that could separate at the bottom of the tank and sometimes provide a breeding ground for certain types of bacteria. If unchecked, these microorganisms could get into the engine and cause jet burn out. To operate the product a 24" (610 mm) lengfii of 0.080" (2 mm) i.d. PVC tubing is fitted with a 0.090 " (2.3 mm) tubulature at one end and a metal clip at the other. The tube is connected to the valve button and the clip is attached to the rim of the inlet pipe of the fuel tank. A complete mixing action results when the aerosol and jet fuel hose are actuated simultaneously into the tank. A similar delivery tube is sold by Chemtronics Inc. (Hauppauge, NY) as their "Vibra-Jet" Aerosol Pulsating Device. It consists of a polypropylene 0.090 " (2.3 mm) connector to the valve button, attached to a 26 " (660 mm) section of 0.080 "(2 mm) i.d. polyurethane tubing, which in turn is attached to a 5.50" (140 mm) section of 3.5 mm i.d. polyurethane tubing on the outside and a 17 mm stub of 0.090 " (2.3 mm) PP tube on the inside, making a three-ply joint. At the end of the large tube there is a similar junction to accommodate a 7 " (178 mm) length of the 0.090 "(2.3 mm) PP tubing.
Aerosol Valves 179 Figure 15. Two-Piece Specialty Actuators Three actuator slots are available for the S-64 Tilt Valve by Summit Packaging Systems, Inc. When used in conjunction with a Solvent TF (CC12F.CF2C1) or 1,1,1- trichloroethane (CH3.CCI3) type aerosol cleaner and degreaser spray the device provides a pulsing or vibrating "solvent impact" action that dislodges hard-to-remove contaminants, penetrates surface pores and improves overall cleaning, lubrication, moisture displacement and other desired effects. Unusual actuators are sold by several valve companies. For rug shampoos, certain garden sprays and other products which are applied with the dispenser inverted, Precision provides their 01-06 Series "Satellite" version and Summit has a similar #72304 Series in three slotted fan-spray models for their S-63 tilt-valve. These actuators are about 1.5 "(38 mm) in diameter and have a press pad. The Summit design is illustrated in Figure 15 on this page. Other inverted-use actuators include the Summit #70039 open tire actuator, #72500 nylon open foam spout and #70059 PP vertical spray head with 0.020"(0.51 mm) M.B.U. insert. Both Seaquist and Precision offer aerosol valve filters that are integral with the tailpiece section of the valve body. The Seaquist filter is provided only for their popular NS-31 valves. These filters can hold back foreign particles down to 0.002 " (0.05 mm) in mean diameter, such as cardboard fibres, lint and certain insoluble materials which occasionally form in the container as the concentrate ages or as tolerable amounts of corrosion products develop. The Seaquist 262 mesh nylon filter is sonically welded to the bottom of the valve body. The use of filters may be contraindicated for moderately viscous products if they impede the flow into the body to an undesirable degree. An interesting valve accessory has been developed by Tor Petterson Associates (Rancho Palos Verdes, CA) called the CliXon system. It is designed to replace electrically operated timed aerosol dispensers which produce a brief spray every so often until the container becomes empty. The invention centers around a cuplike affair containing a permeable barrier. Product enters the lower area through the stem of an actuated valve and passes slowly through the membrane to pressurize the upper area. When a sufficient pressure has been attained a concave disc everts, thereby opening an aperture to release the pressure. Once the pressure has dissipated, the disc reverts to its original shape and closes the orifice. The operation is illustrated in Figure 16 below. The company states that models developed thus far have been able to dispense the contents of a typical 16 oz. (454 g) container in time periods ranging from several minutes to several months. Discharge intervals extend from one second to six hours. The amount of product dispensed ranges from a few mg to about one g. To our knowledge, products incorporating this invention are not yet on the market. Modifications include the Pulsair (for high precision) and the Pulsmatic (for industrial uses). 1^ * •*• -*J..*-..:*,..tr **»**• *tlpllllt <H#; K-„ ■r SPRAY PROFILE 40 30 20 10 Discharge Zones . Accumulating Zone Time in Minutes Figure 16. CliXon Dispensing Cycle, Also A Spray vs. Time Profile
180 The Aerosol Handbook Valves for Antiperspirants, Body Powders and Powder Type Spot Removers PRECISION VALVE CORPORATION Actuator Stem Body Stem Gasket Mounting Cup Dip Tube Spring 01-6280 0.020" 04-0562 0.024" ringed 07-3468 0.062" x 0.025 "VT 05-0320 Low durometer 12-8700 Conical, lipped & eponed 09-3520 0.050" capillary 06-6044 0.020" stainless steel SEAQUIST VALVE COMPANY (author's suggestion) Model No. Actuator Stem Body Stem Gasket Mounting Cup Dip Tube Spring NS-31 0.020" two-piece 2 x 0.018" Acetal-pink 0.025 "VTacetal-yellow Buna, Shore A Durometer of 75 Flat, dimpled. 0.75# ETP epoxy-coated t/b. 0.050 "capillary 0.020 " stainless steel SUMMIT PACKAGING SYSTEMS, INC. Model No. Actuator Stem Body Stem Gasket Mounting Cup Dip Tube Spring SV-73 (Vertical) 01-6380 0.020" 04-0801 2 x 0.020" 07-3478 0.062" x 0.030"VT 05-0301 Low durometer 12-8600 Conical, lipped & eponed 09-3520 0.050 "capillary 06-0101 0.023 "stainless steel 0.019" RT 824000 or 0.020 "ST 821000 or 0.020" STD 807000 0.020" 101007 0.062" RE x 0.025" VT 439001 0.050" Buna B50000 0.063 " Flat Epoxy Bottom 025011 0.042 " i.d. Capillary 65061-0208 0.034" stainless steel 634000 Valves for Hair Sprays and Personal Deodorants PRECISION VALVE CORPORATION Actuator Stem Body Stem Gasket Mounting Cup Dip Tube Spring 01-1406 0.018 "FT 04-1215 0.016" 07-0020 0.025" x 0.013"VT 05-0310 BunaN 12-8700 Conical, lipped & eponed 09-2010 06-6010 Stainless Steel SUMMIT PACKAGING SYSTEMS, INC. Model No. Actuator Stem Body Stem Gasket Mounting Cup Dip Tube Spring SV-73 (Vertical) 0.016 "STD 854000 0.016" 101005 0.020"RE x 0.013 "VT 239016 0.050" Buna B50002 0.102"Flat, plain 033010 Standard 200000 0.033 " stainless steel 633000 21-8541 0.013 " MB concave BOF* 04-1220 0.018" 07-0093 0.020" x 0.016"VT 05-0330 Neoprene 12-8700 Conical, lipped & eponed 09-2010 06-6010 Stainless steel ♦Alternately, 01-5008 0.016 "MBST S-63 (Tilt) 0.016" MB Disc 70001-0020 0.013 "63009-0004 0.016" RE x 0.016 "VT 63001-0066 0.058" Neoprene 63000-0580 0.063 " Flat, epoxy bottom 63000-0410 Standard 200000 0.023 " stainless steel 65003-0005 Note: For both Precision and Seaquist the second column selections are preferred for personal deodorants or rather dry hair sprays.
Aerosol Valves 181 Valves for Cleaners, Starches and Polishes PRECISION VALVE CORPORATION Actuator Stem Body Stem Gasket Mounting Cup Dip Tube Spring 01-8708 0.016 " MBST (light spray) 01-8718 0.020 " MBST (heavy spray) 04-8673 2 x 0.020 "(recessed taper) 07-1901 0.080" 05-0310 Buna N 12-8700 Conical, lipped & eponed 09-2010 06-6010 Stainless steel SUMMIT PACKAGING SYSTEMS, INC. Model No. Actuator Stem Body Stem Gasket Mounting Cup Dip Tube Spring SV-73 (Vertical) 0.016" MB 900101 0.025 " 105001 0.062" RE 239000 0.050" Buna B50002 0.130" Flat, epoxy t/b 040013 Standard 200000 0.033 " Stainless Steel 633000 01-5008 01-5018 04-1270 07-1901 05-0310 12-8700 09-2010 06-6010 0.016" MBST (light spray) 0.020" MBST (heavy spray) 2 x 0.020" 0.080" Buna N Conical, lipped & eponed Stainless steel S-63 (Tilt) 0.016" MB 70055-0003 or -0014 0.030" 63011-0004 0.062" RE 63000-0066 0.058" Buna 64000-0019 0.063 " Flat, epoxy t/b 63000-0412 Standard 200000 0.023 " Stainless Steel 65003-0005 Suggested Valves for Various Products Some valve manufacturers list suggested specific valve combinations for various standard aerosol products. They should be regarded as starting points, since each marketer may have his own unique ideas about what constitutes an acceptable spray pattern. A large degree of supplier interchangeability can be managed by maintaining the same orifices, gaskets and other attributes during the development of alternate or second-source valve specification. It would be too space consuming to list valve possibilities for large numbers of aerosol products, but three have been selected for examples. They include (a) the antiperspirant, body powder and spot remover type, (b) the hair spray and personal deodorant type, and (c) the cleaner, starch and polish type. The dip tube lengths for the valve suggestions on these pages can be determined roughly by reference to Table VIII on page 174. In all cases the dip tube length should be confirmed by making tests in the proposed formula. The bottom of the can may be perforated and then removed to check the dip tube for any length adjustments due to swelling or possibly shrinking in the product. When ordering dip tubes any notched or bias cut ends should be specified, if these are desired. It is suggested that technical service personnel at the valve companies be consulted to determine optimum product assembly. Future The wealth of innovations that have characterized the valve making industry in the past may logically be expected to continue into the future. For example, the Precision Valve Corporation has recently developed a stem orifice system that permits a faster delivery rate valve than they had previously. The company has also started using their "Density Pack" technique of vibrating an extra 50% or so valves into standard cases. Thus a typical 2000-pack box can be made to hold 3000 valves. Boxes currently cost just about $1.00 each, so the cost savings from this aspect alone would amount to $0.17/M in the example mentioned. Consideration is being given to bulk-pack collapsible containers, sized to fit on standard pallets. These could be returnable. New button styles are under development, including some radically different types which are still in the confidential stage, while patent positions are being pursued. Many of the newer sprayheads can be expected to be slightly larger at the top than at the base, to facilitate rapid removal from multi-cavity molds. Even the spring is under study. A process for rough chromium plating of steel springs is being considered as an alter-
182 The Aerosol Handbook nate to the use of SS-302 , SS-316 or Nitronic-50 steels. In fact, at least two valve manufacturers have active programs underway to eliminate the coil spring entirely for some product types. The new designs would allow the base of the stem to expand a funnel-like split hollow cone of a specific plastic, spreading it reversibly. The resiliency of the thin plastic chives would cause the stem to return upward after use. There are many other programs underway. Some relate to the inward clinching or rolling attachment of special valve cups to the top finish of OPET and other plastic type aerosol bottles up to 50 cu. in. (793 ml) in size. Others are still confidential and cannot be described at this time. In summary, the industry can anticipate the continuation of a high level of innovation from the valve makers in the future. Table VIII CSMA "A-D Dimension" Chart for Suggested Dip Tube Lengths Can Size 202x200 202x214 202x314 202x406 202x509 202x700 202x708 Spratainer Spratainer 207.5x509 207.5x605 207.5x701 207.5x708 211x413 211x604 211x612 211x713 300x709 Nominal Fill 2oz. 3 oz. 4 oz. 6oz. 8 oz. 9 oz. 10 oz. 6oz. 12 oz. 12 oz. 14 oz. 16 oz. 16 oz. 12 oz. 16 oz. 18 oz. 20 oz. 24 oz. CSMA. Standard 2'%j" 3'%,- 4%," 4l%," 5*%," 7'%," 7"/3," 4*%2" 4"/»" 6%2" 7%," 7*%," 8%," 5'%2" 6^%," 7'%,* 8'%j" 8%," Standard (mm!) 60. 84. 106. 122. 149. 186. 197. 118. 121. 156. 179. 198. 210. 140. 176. 191. 213. 208. C.S.M.A. Jumbo (in.) 3%," 4%," 4*>/»" 5"/»" 7«/»- 7'%," 4"/»" 4l%," 6 6"/3," 7»%," 8%," 5'%,- 6»/»" 7'%2" 8'%,- 8%,- Jumbo (mm) 81. 103. 117. 146. 184. 194. 114. 117. 152. 176. 195. 206. 138. 175. 189. 211. 206. Aluminum Tube Size Iy4x4y4" I%x2'/r 1 %x3- 1%x3'tf«" 1ttx3"/i«" 1ttx4vi«" 1'/<>x4"/i«" 1ttx5" 1ttx5*i»" 1'/ix5%- lVix6!6- ly4X4'/i" ly4x5Vi" 1J/4X6V<!* 2.089x4"/i«- 2.089x5'/i- 2.089x6" 2.089x6'/i" Nominal Fill 2.5 oz. 1.75 oz. 2oz. 2.5 oz. 2.8 oz. 3.3 oz. 3.8 oz. 4oz. 4.3 oz. 4.5 oz. 5oz. 4.9 oz. 5.9 oz. 7.0 oz. 6.8 oz. 8.2 oz. 9oz. 9.7 oz. c.s:m.a. Standard (in.) 4»%," 2'%,- 3" 3l%2" 3»%," 4%," 4^%," 4"/»" 5'%,' 5^%,- 6'«A2- 4'%j- 5'%j" 6'%j- 4"A2- 5'%j* 6%j- 6'%j- Standard (mm) 122. 62. 76. 95. 92. 105. 117. 124. 137. 151. 165. 113. 140. 165. 121. 140. 154. 165. C.S.M.A. Jumbo (in.) 4l%2- 2'%2" 2^%," 3»%," 3'%," 4%2" 4'%," 4l«/i," 5'%,' 5l%," 6'%,' 4'%," 5'%," 6'%," 4»%," 5'%," 6" 6'%2" Jumbo (mm) 121. 60. 75. 94. 90. 103. 116. 122. 135. 149. 164. 111. 140. 164. 119. 138. 152. 164. Courtesy of Precision Valve Corporation.
183 AEROSOL COVER CAPS 6 Aerosol cover caps came into existence about 1951, as a necessary adjunct to the new one-inch (25.4 mm) valve. The protective covers used before this, such as the flat 211-diameter (65 mm) dust lids, "Derby Domes" and small metal clips or shrink-set plastic valve wraps, are not usually thought of as cover caps. Aerosol cover caps have a number of functions, such as: a. They physically protect the spray head from possible damage if the dispenser is dropped. b. They prevent the actuator from discharging the contents during storage, due to the pressure of overlying cases. c. They prevent cases from becoming bulged or split during storage, due to the pressure of overlying cases. d. They avoid the accumulation of dust or dirt on the valve and (often) on the dome of the can. e. They provide tamper-proof or child-resistant attributes, if desired or needed. f. They enhance the general appearence of the container, sometimes adding height and volume, covering double seam constructions, or assisting in the development of color and decoration schemes. g. They can be imprinted with short but important messages, such as "Shake Before Use." h. Full-diameter plastic cover caps are thought to provide a degree of thermal insulation to the dome area of cans if they become involved in a warehouse fire, thus reducing the hazard slightly by delaying rupture and release of possible flammable materials. In some instances cover caps have added a substantial degree of novelty or utility to the package. Some
184 The Aerosol Handbook Figure 1. Slotted Cover Cap with Extension Tube Top-slotted cover cap with friction-fitted extension tube (patent pending). Saves labor cost of applying side wall of dispenser using either a rubber band or Scotch Tape. aerosol fire extinguishers use caps in the shape of a fireman's helmet. One used with an absorbant silica product is molded with plastic bristles on the top surface for removing the spent powder. The now obsolete "Sun- brella" suntan lotion product used a yellow cap in the shape of an umbrella for quick identification and interest at the point of purchase. A similar sunscreening product of Japanese origin carried a yellow cap in the shape of a delicate parasol. Finally, an interesting cap is sometimes used for products requiring valve button extension tubes, such as lubricants, car lock de-icers, adhesives and similar specialty items. The top of the cap is slotted to hold the tube on a friction fit basis. If the units are hand-packed, extension tubes having lengths of up to twice the can diameter can be accommodated readily in regular shippers. A typical slotted cap and extension tube is shown in Figure 1. A special form of the cover cap is the actuator cap, where the actuating pad is recessed in the plastic cap to prevent accidental operation. At the same time it provides a convenient way of discharging the contents without the need for first removing the protective cover. The actuator itself may be a large or small button, or a lever hinged to the cap. These special caps have an advantage of being highly directional, so that customer mishaps caused by misdirecting the spray are rarely encountered. These dual-purpose fitments have become very popular in recent years. They do increase packaging costs in most cases and cannot be used for certain aerosol products, such as paints and coatings. The first aerosol cover caps were rather small, designed to snap over the outer edge of the one-inch (25.4 mm) valve mounting cup. They quickly became known as one-inch caps. Actually, the term is a misnomer, since these caps have outside diameters of about 1.45" (36.8 mm). They were made in enameled tin- plate, polyethylene, polypropylene, polystyrene and other materials. One fancy cologne product even had a cap made of polished wood. The one-inch caps are now rather uncommon, although they do represent the practical ultimate of packaging economy. They have been replaced largely by plastic full-diameter caps and actuator caps, since marketers discovered that these larger versions had advantages of aesdietics, functionality and apparent package size enhancement that far outweighed the modest price increase. The one-inch cap is compared widi several full-diameter cover cap designs in Figures 2, 3, 4 and 5. Aerosol cover caps and their spray-cap counterparts represent a business volume of about 2.2 billion units per year and a dollar volume of about $4 million (1981 and 1982 basis). Today, nearly all the caps are of plastic, due to economics. They are made by a relatively small group of plastics molding companies, but also by a few marketer-fillers and contract fillers. Considering aerosol cans with one-inch valves, there are technically four areas where the cap can be locked into position on the dispenser. a. The outermost cut edge of the valve mounting cap. This applies to all one-inch metal and plastic cover caps, to full-diameter double shell plastic cover caps and to two-piece fabricated metal caps of a similar shape. b. A "snap-lok" ring around the can dome, just inside die countersink area. This applies to single shell plastic cover caps of a particular set of designs, where the base is thickened so that lugs can hold the fitment onto the dome contour, while still allowing the cap to sit upon the top double seam for bodi stability and appearence. A ring of four dome dimples has been used in the past for the same purpose, but the dome became rather ugly as a result and the design was discontinued about 1971.
Aerosol Cover Caps 185 c. The top double seam of the can. Two cap designs are available in this case, but both snap over the double seam and are held firmly in place with lugs. The first of these caps was produced about 1958 with the design shown in Figure 4. When attached, it produced a final dispenser shape consisting of a cylinder with an annular ring around it. The necked-in can became available in a limited way about 1967, and for these units a full-diameter, straight wall, internally ribbed cover cap was made to fit over a double necked-in top seam construction to give the package a perfectly cylindrical profile. d. The crimping indentations in the valve cap. (Obsolete) This full diameter cover cap style had a double shell construction. The inner shell was either straight or vee split, for flexibility, and had lugs to fit within the crimping indentations. It was phased out because the valve button was often pushed to one side rather severely when the cap was removed in the normal way. Several full diameter valve actuators still use this method of attachment. In the foreseeable future the necked-in can will undoubtedly become more important, due to simple economics, and with it the straight wall, single shell, over-the-rim plastic cover cap. In North America, as of 1982, this can design had not yet become a production item of major significance. As a consequence, the cover cap is thought to be produced by only one U.S.A. supplier: Risdon Corporation's Dispensing Systems Division, as their Models #82-02-1 (202- or 52 mm diameter) and #82-11-1 (211- or 65 mm diameter), although Southern Can Company may elect to act as a distributor of these caps for cans of all diameters. In Europe, where necked-in cans were pioneered by the Metal Box Limited firm and are now fairly commonplace, Metal Box and several other firms now produce a range of these caps for use with tinplate cans from 114- (45 mm) diameter to the 211- (65 mm) diameter. One of the more critical appraisals for a cover cap is the firmness of its attachment to the rest of the package. The fit must be snug and tight, but not so tight that it cannot be taken off except by the application of brute force. Many persons seem to have a preference for picking aerosols up by the cover cap or spray cap. In this SI SMOOTH TOP ■ EASILY PRICE MARKED Figure 2. Drawing of Old Style One-Inch Cap The old style one-inch caps are gripped by the outer edge ot the valve mounting cup. s over valve cup FLUSH KVITH BEAD OF CAN Figure 3. Drawing of Double Shell Cap It is the inner shell of the double shell cap that grips the container, fitting around the outer edge of the mounting cup. FITS OVER OUTER HEAD Figure 4. Drawing of Rim Snap Cap Rim snap caps are of single shell construction. The outer rim of the cap snaps over the chime to hold the cap in place. LOCKS INSIDE SPECIAL RECESS IN DOME OF SNAP LOCK CAN COMPACT AND EFFICIENT Figure 5. Drawing of Snap Lock Cap The snap lock cap locks into position by being pressed into a ringlike depression in the countersink area of the dome.
186 The Aerosol Handbook Figure 6. "Lift-Up" Cap Unique "lift-up" cap used on some food products on a Mira-flo aerosol can. The lever provides easy removal. case a relatively loose cover cap may come free of the can, causing it to fall. At least a few lawsuits have resulted from foot injuries sustained in retail outlets because of loose-fitting caps. During the mid-1960s a CSMA Committee took a hard look at the problem of loose cover caps and eventually suggested the use of a simple "go/no-go" testing device developed by Gilbert Plastics, Inc., as a standard for measuring the gripping force between the one-inch cap and the valve cup. The Aerosol Cover Cap Fitment Gauge or Cap Gauge, as it came to be called, consists of a solid mass of hardened steel, weighing 1 lb. 7 oz. (652 g) and having the dimensions shown in Figure 8. The A, B, C and D dimensions are critical and should be machined accurately. The A dimension is the most critical of the set. In the event metal caps are tested, this diameter should be checked periodically for possible wear, using a micrometer. To perform a fitment test, the cap is assembled over the rim of the simulated valve cup portion of the gauge block. The unit is then lifted carefully by the cap and slowly tilted to an angle of 30° with the vertical. The cap should remain in place. This method, while certainly useful, applies only to separating loose caps from others. It does not detect extra tight-fitting caps, nor can it be used with any caps that attach at the snap-lok or around the top double seam. Since the preponderance of cover caps are of these last two varieties, some additional method had to be found. During the late 1970s, at least one marketer developed a rather interesting method for assessing the holding quality of these full diameter cover caps. In this case, a small hole is bored through the top of the cap, exactly one inch (25.4 mm) from the axis. A thin string is knotted and inserted through the hole, after which the cap is snapped onto the test can. The test can should previously have been measured with a micrometer, so that it is known to have a representative average diameter for that dimension needed for a good cover cap fit. The can is fixed in a testing jig and the string led upward at an angle of 30° with the vertical, then through an eyelet (to maintain the angle), after which it is attached to a spring gauge. By slowly pulling upward on the spring gauge the tension (actually torque) needed to dislodge the cap can be determined readily. The acceptable force range can be derived from panel or consumer tests. If the cap manufacturer concurs and agrees to the test and applied benchmark as a valid measurement of the fit quality, then the method can be applied as part of the incoming inspection process. Without an unwieldy degree of sophistication and inspection time, the methods cannot be applied to "worst case" cover cap retentions. These would occur at the maximum can diameter and minimum cap diameter, for the tightest fit, and the reverse for the loosest fit. By using a test can from the lot to be actually mated with the cover caps during production, a satisfactory test result and prognosis can almost always be obtained. Overly loose and tight cover caps are still an occasional problem, and have resulted in both in-plant rejections and field problems. Although cover caps are produced in steel molds of precise dimensions, the shrinkage of the molded article can vary according to (1) plastic composition (including plasticizer type and amount) (2) the type and loading level of pigments, and (3) the molding temperature. In one memorable case, a marketer changed his full-diameter cap color from a pastel blue to a dark blue and had to reject the lot because the new caps were almost impossible to apply and remove from the cans. Cover cap manufacturers use a still more sophisticated method for measuring cap retention. The cap is attached, either to a standard aerosol can or to a machined and hardened steel dummy, with ideal dome and valve cup dimensions. The assembly is then fixed in a horizontal position and a dial-reading force gauge is positioned on a vertical column so that the force bar is directly over the top end of the cap, where the side wall joins the top. Using a hand lever, pressure is applied increasingly until the cap is dislodged. In the case of child-resistant caps, grip retention is monitored by physically pulling caps off the cans. In the case of actuator caps, the very strong attachment of cap to can is deliberate. They are not meant to be removed. The shape and size of the hold-down lugs
Aerosol Cover Caps 187 are adjusted so that these caps require such drastic removal methods that they are often stripped of their lugs, deformed or destroyed in the process. A similar very strong attachment is used for tamper- proof caps. This type of cover cap is used for paints, coatings and other products to prevent capricious or malicious actuation. A tamperproof cap is also child resistant. It must be pried open by inserting a screwdriver through a slot and using it as either a torsion bar or as a lever, depending upon cap design. The smaller versions are shaped to fit inside the valve cup, and the attachment is made by means of a lower skirt shaped to snap into the crimp indentations. A typical version is the Snap-Lox Model 910 by Newman-Green, Inc. Other models include full-diameter varieties, where the connection is made around the outer cut edge of the valve cup, using a rather heavy flange. The double shell Gilbert Model No. 306-SD is typical of these designs. These caps are generally made from high-density polyethylene (HDPE). Cover Cap Dimensions Plastic cover caps are available for the 114-, 202-, 207.5-, 211- and 300-diameter tinplate cans, plus 20 mm valve containers, various aluminum tubes and special collared fittings. They come in various heights. One of the tallest is the Gilbert Model 301-EH, with a height of 2.641 " (67.1 mm), designed to fit over the Clayton and Super Whip type valves characterized by their tall dispensing stems. Conversely, cover caps can be quite small indeed; one of the smallest fits over the actuator pad of foam valves. A typical protective cover of this variety measures about 1.19"x0.31" high (30.2 x 0.79 mm) and may be ordered optionally already fitted onto the foam spout by the supplier, so that the filler has only one assembly step on the production line instead of two. A listing of 70 cover caps is provided in Table I, showing most of the sizes provided by six major cap suppliers. Table I Aerosol Plastic Cover Cap Identification Chart Container Diameter General Description Total Height Gilbert Aerosol Cover Cap Manufacturer's Stock Number Imperial Sunbeam Atco Pharmaplastics Paragon Plastics 5/8" (20 mm) (20 mm) (20 mm) (20 mm) (20 mm) (20 mm) (20 mm) Straight wall - to fit over 5/8 " diameter tube Straight wall - to fit over 20 mm valve ferrule Serrated, curved wall - to fit over 20 mm valve ferr. Serrated, curved wall - to" fit over 20 mm valve ferr. Serrated, curved wall - to fit over 20 mm valve ferr. Inside ribbed, curved wall, 1.250" o.d. - fits on ferrule Plain reverse taper - to fit over 20 mm valve ferrule Plain reverse taper - to fit 1010 collar for use with the Wheaton bottle No. RS-1668 1.125" 1.250" 1.250" 1.375" 1.875" 1.469" 1.656" 1.656" 901 902 (20 mm) Plain reverse taper - to fit 1500 collar for use with the Carr-Lowry bottle No. 4303 1.469" 0.625 90-A 90-T Series 160 Series 110 Series 100 Series 150
188 The Aerosol Handbook Table I (Continued) Aerosol Plastic Cover Cap Identification Chart Container Diameter General Description Total Height Gilbert Aerosol Cover Cap Manufacturer's Stock Number Imperial Sunbeam Atco Pharmaplastics Paragon Plastics (20 mm) Fine ribbed, dome-top, band- 1.906" ed cap with short internal ribs (20 mm) Fine ribbed, dome-top, band- 1.906" ed cap with short internal ribs Series 200 Series 210 (20 mm) Ribbed, flat top, banded cap 1.906" with short internal ribs (20 mm) Ribbed, flat top, banded cap 1.906" with long internal ribs (20 mm or one-inch) (One-inch) (1.5" tube) 114-diam.- necked-in 202-diam. Spra-tainer 202-diam. (52 mm) 2.089 "diam. (52 mm) 202-diam. necked-in 202-diam. (52 mm) 202-diam. (52 mm) Double ribbed overcap to bottles or one-inch valve i Double ribbed "Stacker" Cap for 1.50" aluminum Single shell rim-snap, by Box Ltd. and Southern C Co. (only) Smooth, straight wall. Double-shell. ,» Double-shell for Peerless fit cups cap tube Metal an Tube aluminum monobloc Single-shell, rim snap. By Metal Box Ltd. & Risdon Single-shell, rim snap > > Single shell, snap-lock , 1.625" 1.000" 1.500" 1.750" 1.516" 1.219" 1.313" 1.375" 1.969" 1.719" 1.500" 1.313" 1.375" 1.391" 1.437" 1.516" 1.969" 2.020" 1.250" 1.346" 1.469" 1.485" 405 1100 100 209 209T 201 201T 201 XT 1202 202-diam. Spra Guide (Directional 1.375" (52 mm) Spray) 202-diam. Tamperproof Cap. Double 1.375" (52 mm) shell. 202-diam. Spra Mate (Directional 1.625" (52 mm) Spray) 202-diam. Single shell, rim snap with 2.000" (52 mm) polyethylene brush on top 100SC Series 220 Series 230 Series 400 40B Series 450 1.5F Series 550-560 10D Series 950-951 202-DD 202-DS 20D 202-RS 202-RS 20A 202-S 202-SG 202-CR TP-202-DS 202-SM 202-RB 2260-RB Series 940 Series 960 Series 930 Series 800 2020R XT2020R 202 IR T202IR
Aerosol Cover Caps 189 Table I Aerosol Plastic Cover Cap Identification Chart (Continued) Container Diameter 207.5-diam. (60 mm) 207.5-diam. (60 mm) 207.5-diam. (60 mm) 207.5-diam. (60 mm) 207.5-diam. (60 mm) 211-diam. 211-diam. (65 mm) 211-diam. (65 mm) 211-diam. (65 mm) 211-diam. (65 mm) 211-diam. (65 mm) 211-diam. 211-diam. necked-in 300-diam. (76 mm) 300-diam. (76 mm) 300-diam. (76 mm) 300-diam. (76 mm) General Description Double-shell Single-shell, rim snap Single-shell, snap-lock Spra Guide (Directional Spray) Spra Mate (Directional Spray) Double-shell dome-top Double-shell Single-shell, rim snap Single-shell, snap-lock Spra Guide (Directional Spray Tamperproof Cap Tamperproof Cap - Flat finish Single-shell, rim snap. Made by Metal Box Ltd. & Risdon. Double-shell Single-shell, rim snap Single-shell, snap-lock (Not made; weakens dome.) Spra Guide (Directional Spray) Total Height 1.656" 1.688" 1.719" 1.844" 1.825" 1.750" 1.875" 1.688" 1.688" 1.625" 1.625" 1.688" 1.969" 1.688" 1.844" 1.859" 2.031" 2.641" 1.688" 1.813" 1.930" 1.750" 1.656" 2.000" 1.656" 2.088" 1.656" 1.672" 1.688" 1.766" 2.125" 1.875" Gilbert 809 801 1801 309 305 309T 301T 301 XT 301 EH 1301 306 509 501T Aerosol Cover Cap Manufacturer's Stock Number Imperial Sunbeam Atco Pharmaplastics 207-DS 2 HDD 211DS 211-RS 211-CR 211-CRF 300-DS 207.5-DS 207.5-RS 207.5-SG 207.5-SM 211-DS 211-RS 211-ST 211-SG TP-211 300-DS 80D Series 970 30D Series 910 30T 50D 300-SG Paragon Plastics T207.5IR 211DW T2HOR XT2HOR XT211IR Notes: a. All height dimensions are approximate ( ±0.031 "). Manufacturers tolerance for height is usually ±0.015". b. Cover caps are often available in polypropylene as well as polyethylene. c. The tabulation is not represented as complete. Current data should always be obtained from the suppliers. d#. A single-shell, rim snap cover cap for 300-diameter necked-in cans is experimental at this time and available from the Southern Can Company. e. Lines of plastic cover caps are available from most valve companies and from several other firms. They are not included here only because of lack of space. f. As an example of the terminology used by cap suppliers, Imperial caps are designated DS for double shell and flat top, DD for double shell with domed top (center area), RS for single shell and flat (matte finish) top and CR for child-resist ant (with domed top- center area).
190 The Aerosol Handbook Table II Variation of Cap Wall Thickness With Diameter Can Diamete: (in.) 114 202 207.5 211 300 r (mm) 45 52 60 65 76 Typical Cap Wall Thickness (in) 0.032 0.033 0.035 0.042 0.048 (mm) 0.813 0.838 0.889 1.067 1.219 Thicker constructions provide more deformation resistance, greater load-bearing ability and more crush resistance if the aerosol is dropped. There are two general groupings in terms of cap diameter, the various "full-diameter" caps and those which are much smaller and fit direcdy over 13 mm, 20 mm and one-inch (25.4 mm) valves. The full-diameter types are slightly less than the maximum can diameter if they fit on snap-lock can domes, and slightly larger if they fit over the top double seam, as in the rim snap varieties. Where the can is double necked-in at the top, then caps that fit over the double seam are truly the same diameter as the can; but this is the only case. For 20 mm closures full-diameter cover caps are often vaned inside, so that three or possibly four radially situated vanes fit snugly against the outer wall of the valve ferrule and allow the cap to be made in any desired diameter, up to the diameter of the bottle or aluminum tube as a practical limit. A problem sometimes experienced with these caps is that die consumer may attempt to remove them by pulling them upward at an angle. If one of the vanes then forces the valve button to one side there probably will not be any damage, but the actuator will take on an unsightly appearence, unless it is straightened. Most plastic cover caps are engineered to provide a wall angle of about 1° to 1.5° with the vertical. This is to facilitate removal from the mold after injection. Wall thicknesses vary with can diameter, and typical values are about as shown in Table II. Although the steel molds used commonly to make 8, 16 or even more caps in each operation are machined to very precise dimensions, the finished cap dimensions are less exact because of shrinkage. Plastic shrinkage Table III Dimensional Comparison of 21 Typical Aerosol Cover Caps General Type Over valve cup Over valve cup Over valve cup Over rim Over rim Over rim Over can chime Double shell Double shell Double shell Over rim Double shell Over rim Over rim Over rim Double shell Double shell Double shell Double shell Over rim Double shell Can Size (All) (All) (All) 202 202 202 202 202-Sp* 202 202 207.5 207.5 211 211 211 211 211 211 211 300 300 Model No. 401 405 411 201 202-T 202-XT 201-CC 100 209 209-T 801 809 301-T 301-XT 301-EH 309 305 309-T 306-SD** 501-T 509 Overall Height (in.) 1.438 1.438 1.438 1.391 1.516 1.969 1.391 1.516 1.219 1.469 1.844 1.656 1.859 2.031 2.641 1.656 2.688 1.969 1.688 2.125 1.656 (mm) 36.52 36.52 36.52 35.33 38.51 50.01 35.33 38.51 30.96 37.31 46.84 42.06 47.22 51.59 67.08 42.06 42.88 50.01 42.88 53.98 42.06 Overall Diameter (in.) 0.969 0.969 1.078 2.066 2.066 2.066 2.250 2.066 2.000 2.000 2.555 2.266 2.766 2.766 2.766 2.469 2.469 2.469 2.469 3.101 2.750 (mm) 24.61 24.61 27.38 52.48 52.48 52.48 57.15 52.48 50.80 50.80 64.90 57.56 70.26 70.26 70.26 62.71 62.71 62.71 62.71 78.77 69.85 I.D. at Contact Surface (in.) 1.265 ±0.012 1.265 ±0.012 1.265 ±0.012 2.185 ±0.008 2.185 ±0.008 2.185 ±0.008 2.175 ±0.015 1.269+0.006 1.269 ±0.006 1.269 ±0.006 2.485 ±0.015 1.269 ±0.006 2.701 ±0.006 2.701 ±0.006 2.701 ±0.006 1.268 ±0.006 1.268 ±0.006 1.268 ±0.006 1.216 ±0.006 3.005 ±0.015 1.269 ±0.006 (mm) 32.13 ±0.30 32.13 ±0.30 32.13 ±0.30 55.50 ±0.20 55.50 ±0.20 55.50+0.20 55.24 ±0.38 32.23 ±0.15 32.23 ±0.15 32.23 ±0.15 63.12 ±0.38 32.23 ±0.15 68.61 ±0.15 68.61 ±0.15 68.61 +0.15 32.21 ±0.15 32.21 ±0.15 32.21 ±0.15 30.89 ±0.15*** 76.33 ±0.38 32.23 ±0.15 Number of Tangs 4 4 4 4 4 4 3 3 3 4 3 4 4 4 3 3 3 — 4 3 *For 6-ounce Spra-tainer can. "Tamper-proof - Screwdriver release - slotted cover cap. '"Measured to inner edge of continuous hold-down flange. Models and dimensions are those of Gilbert Plastics, Inc.
Aerosol Cover Caps 191 after separation from the mold will vary according to the cycle speed composition, temperature and other factors. For polyethylenes, it will average about 0.012 "/inch (0.012 mm/mm) or 1.2%. If the mold temperature increases, shrinkage will increase. Non-critical dimensions for cover caps generally have tolerances in the range of ±0.31" (±0.38 to ± 0.79 mm) and are often noted as inches plus fractions on drawings. As a rule, the only really critical dimension is the inside diameter at the contact surface, where the snap-on to the aerosol container is made. Tolerances of about ± 0.006 "( ±0.15 mm) are applied to this dimension. Wall thickness is important from an economic standpoint, since a reduction of as little as 0.001" (0.025 mm) can save 2 to 3% of the plastic weight, depending on cap diameter. Decreased wall thickness invites warping in the cases, crushing if the can is dropped on the cover, a reduction of load-bearing strength in warehouse storage (especially important during hot, moist summer days, when corrugate is weakened considerably) and some reduction of holding power in the connection to the can. Wall thicknesses are generally held to a tolerance of less than ± 0.002" (0.051 mm). Table III provides the overall height, overall diameter and the critical i.d. at the contact area for a group of 21 cover caps made by Gilbert Plastics, Inc., stipulating that the selection of this firm does not imply any recommendation as to dimensions, quality or other attribute. Dimensional development can be more complex than is generally recognized. Cover caps are often engineered rather intricately to provide optimum strength, fit and aesthetics. A case in point is the snap-lock cover cap. As shown in Figure 9, the undertuck dimension on the snap-lock can dome is only 0.003 " (0.076 mm) as a minimum, and the cap must fit snugly to this tiny protrusive ring of metal. The detail of a typical snap-lock cap in this area is provided in Figure 10, in the case of a 207.5-diameter (60 mm) size. The design is further complicated by the inclusion of about two air vents. In some cases, up to twelve or sixteen lugs are used instead of a regular undercut band. Either high density polyethylene (HDPE) or polypropylene (PP) are the preferred plastics for snap-lock cover caps. Air vents are included in nearly all full-diameter caps. This is because residual moisture from the hot tank water may be trapped below the valve cup or on other top areas of the dispenser. If the cover cap acts to Figure 7. European Cap A unique European polyethylene cap, designed to fit around the one-inch valve cup. seal it in, then eventual rusting may result. In the U.S.A., the air vents are simple channels cut inside the cover cap, where it contacts the dispenser. In Europe, a very small breather hole is pin molded through the top surface, near the edge. Both work equally well. A European cap by Metal Box Limited is shown in Figure 9 on the next page. Figure 8. Aerosol Cover Cap Fitment Gauge -1.470'' ■> °-Tl I &* 0.074' ZI ffr 3.500" K=- s: -2.062". 0.125"
192 The Aerosol Handbook 2.487" Reference point at the, snap-lock diameter dimension 0.003" min. _ (0.762 mm min.ji Figure 9. Fitment on a Necked-ln Can Recommended voluntary industry standard cover cap fitment on a 207.5/211-diameter hecked-in aerosol can with snap-lock cap. 2.487" (63.17 mm) is the diameter over the double seam, excluding cross-over area. 2.085 ± 0.004" (52.96 ± 0.10 mm) is the snap-lock diameter. 0.040" min. (1.02 mm, min.) is the length of the snap-lock wall — measured vertically from the maximum snap-lock dimension to the point where the maximum undercut is obtained. Diameter » 2.065 ± 0. 010 1.5° Diam. = 2.280' (Dotted line: One of two vents inside on undercut.) Figure 10. Detail on 207.5 Diameter Snap Lock Cap Plastic cover caps that fit tightly around the valve cup often inhibit the evaporation of moisture. When they are to be used, extra attention should be given to air drying the actuator, stem and inside of the valve cup as effectively as possible to prevent possible staining or rusting. Epon lining the cup may help delay or reduce corrosion, but it rarely prevents it. In the past, other plastics besides HDPE and PP were used, and a few suppliers still offer them. They often present problems. For instance, polystyrene is very sensitive to traces of methylene chloride vapors, tending to soften or even "melt" under conditions of seepage rate often found with formulations containing this strong solvent. Polypropylene (PP) is a good, all- around resin for caps, but tends to become very brittle at temperatures of about 0°F ( - 17.8°C) or less. Conversely, HDPE is useful down to at least -40°F (-40°C) without becoming more than slightly brittle. When changing plastics, keep in mind the different coefficients of expansion/contraction with temperature. Otherwise, caps that are too large or too small may result. Metal cover caps are available, but are generally used with "low aesthetic" tinplate aerosol products, or else, in the case of highly polished, lacquered, ano- dysed, alodysed or enameled aluminum caps, with high quality aerosols packaged in aluminum or glass. The steel utility cap is manufactured by the Sterling Seal Co. and several other firms. Sterling's "No. 7 Outer Protection Cap" is one of the most popular. It is made of tinplate about 0.0156" (0.40 mm) thick and has a curled bottom edge that rests against the can "flat" just below the valve cap. The sealing area has anominal i.d. of 1.288 ", but the connection to the valve cup depends upon three flats or indentations, which make the effective i.d. 1.257 ± 0.005" (31.93 ± 0.13 mm). The side wall is decorated with vertical knurled bar-like depressions and the top has a low ridge around the periphery that can fit into a mating-type indentation on stacker- type can bottoms for stacking in store displays and similar purposes. Thin wall aluminum cover caps are produced by such firms as the Dispensing Systems Division of Ris- don Corp. and Neotechnic Engineering Ltd. These particular companies have made both valves and caps for aerosol products since the 1950's. They have specialized in deep drawn presswork. Ferrule type aerosol valves are produced in 13, 15, 18, 20 and even 32 mm diameters, and aluminum
Aerosol Cover Caps 193 cover caps are available for all of these sizes. In addition, pressed-fitted aluminum collars are made for both glass and aluminum aerosol packs, and these too can be outfitted with aluminum caps. A typical composite can be cited as the Risdon No. 73-20-4 (inverted teardrop) or No. 72-20-4 (swirl design) two-ounce glass bottles, which can be sealed with a 20 mm ferrule valve and then press-fitted with a No. 61-20-3 polished and dye lacquered aluminum collar. The No. 51-20-3 polished and dye lacquered aluminum cap is then fitted over the collar and held snugly in place by means of several small vertical ribs. As an alternate, plastic collars are also available. Aluminum cover caps are usually straight walled and flat-topped; however, they can be obtained with slightly domed tops, ballooned tops, flared bases (Europe only), and flared tops. It is not unusual for major toiletry marketers to have thier corporate name or logo embossed or debossed on the top of these caps for an added touch of elegance. These caps fit onto the appropriate valve ferrule because of a forming process known as cap triangula- tion. They are made out-of-round in the lower wall area, actually pressed into the shape of a very rounded triangle form. The degree of out-of-roundness is almost unnoticeable, actually, but when the cap is slipped over the ferrule, the inner walls provide a friction fit against it in three equidistant points around the circumference. A second option is to provide ribbing for the cap, but generally the aesthetics have caused marketers to shy away from this alternate. Ferrule ribs have been used, but nearly always for the long-skirt ferrules found so commonly with pump-action sprayers. U.S.A., Europe and Japan have developed uniquely styled cover caps that have undoubtedly assisted them in getting on-the-shelf recognition and in expanding their sales. Each marketer must decide if the added cost of a custom closure is worthwhile for his particular product, weighing at the same time the limitations placed on the flexibility of his operations by the adoption of custom rather than stock parts. For example, if he does his own filling at a single location and has his custom caps made internally or nearby, then his transportation problems are minimized. On the other hand, if he has his product filled at widely separated points for national distribution, then there will be an added cost for shipping his custom closures to the remote filling locations. This is not a large factor, since large cover caps and actuator caps can be packed 500 to 1000 per box and from about 275,000 to 600,000 per truckload. Then too, only about 15% of U.S.A. aerosol production is done west of the Mississippi River, where distances are greatest. The marketer who decides to work with stock closures is not particularly inconvenienced. Special colors and printing offer a considerable degree of brand identi- Custom Caps Customized cover caps are available in any size, in both metal and plastic. For example, a major marketer in the U.S.A. currently makes most of his plastic caps and actuator caps. The cost of multi-cavity molds of 16 or more units can easily run into the $60,000 to $100,000 area, so decisions to make special cover caps cannot be made lightly, or for products with sales of less than about 5 to 10 million units per year. Single unit soft or hard molds can be made in a few weeks at a cost of about $10,000 or less, and can be used to turn out perhaps as many as 100,000 special caps for test marketing and other purposes. From this point on the stakes get considerably higher in terms of both capital and waiting time. Nevertheless, marketers in the '4 Figure 11. 114-Diameter Can Necked-ln to a 112 Can A 114-diameter (45mm) aerosol can, necked-in to a 112-diameter (42mm) and fitted with a single shell overcap. The can and cap are made by Metal Box Limited. Like most European caps, this one has a small air vent hole in the top to release possible moisture from the hot tanking operation. The hole is near the decorative recessed ring.
194 The Aerosol Handbook fication. Cap colors can be matched to dominant colors on the can label or lithography. Cap printing can be handled in up to three colors, although this is rarely called for. In some cases, heavy paper hoops are fitted over full-diameter caps to provide the consumer with special information, redemption coupons and other offers. In a few cases the plastic cap is printed with various offers, with directions that the cap be cut with scissors to isolate the coupon, after the can is used up. Actuator Caps The actuator cap was introduced at least as early as 1954, in conjunction with the first productions of RAID insecticide, in Danville, IL. The Schrader Valve Division was responsible for some very early actuator caps, and National Laboratories used them on three of their disinfectant/deodorant sprays back in the fifties. Several difficulties slowed the growth of this packaging adjunct, such as splitting, warping and fitting difficulties, as well as the relatively high costs. About 1961 both "Raid" and "Glade" products (by S.C. Johnson & Son, Inc.) were converted to water- based forms, and presented in very attractive dispensers with well-designed VCA actuator caps. Their many competitors responded, and among other things, this put the actuator cap into the aerosol business in a very big way. Now, some twenty years later, most of the cap makers and valve companies offer one or more designs, some of them quite unique, and the actuator cap is used on a large percentage of all aerosol products. The actuator cap cannot be used on a number of products. For instance, it is contraindicated for paints and coatings, for extension tube items and for viscous products. In some cases, the added cost may not be supportable. But in general it has had a very good recep- Figure 12. Selection of Anodysed Aluminum Caps These caps are for 13 and 20 mm ferrules. Shown also is an aluminum cap of breath freshener under the OSPRAY brand, sold in Europe by Beecham Markenartikel AG (Switzerland) with the label printed in English and German. The bottle cap is a 20 mm polyethylene type. tion. A number of distinct advantages have led to this degree of success: a. The package is easier to hold and operate. b. The rather unsightly can dome is not exposed—in the case of full-diameter caps. c. Directionality, and thus consumer safety, is markedly enhanced for spray products. d. No overcap need be removed and replaced. e. Considerably more aesthetic appeal is possible. f. A sense of larger proportions is achieved. g. Special actuating features can be obtained, such as a brush top used for certain upholstery cleaners, where the product is actuated into the brush area. h. Replaces the standard actuator and overcap, so that the cost of these components can rightfully be subtracted from that of the actuator cap. Figure 13. Mark Series Caps by Metal Box Ltd. The first three styles (I to r) are full diameter, for regular and necked-in 114 (45 mm), 202 (52 mm), 207.5 (60 mm) and 211 (65 mm) ETP cans. The last two styles fit over the valve mounting cup. The middle cap style is also made by Plasticum, bv (Tilburg, Holland) for the 112/114 and other necked- in cans.
Aerosol Cover Caps 195 i. The dispenser can be dropped to the floor in any position, probably with no damage. j. Diptube orientation is more reliable. k. The large actuator pad reduces finger fatigue during extended spray periods. 1. The unit is instantly available for use. m.Certain designs qualify as "Child Resistant" and "Tamper-proof". A "Pressure-release" version is under development in California. Child Resistant Caps Under the Poison Prevention Act of Dec. 30, 1970, the Consumer Product Safety Commission (CPSC) has the authority to develop and enforce regulations governing the child-resistant packaging of dangerous consumer products. Since their purvue is confined mainly to household products (although the Consumer Product Safety Act appears to give them much broader authority in the field of safe packaging), the Environmental Protection Agency (EPA) moved to require child-resistant packaging in the case of economic poisons as well. Under these almost identical regulations, "special packaging" is designed to protect children from serious injury or illness that might otherwise result from the handling, using or ingestion of harmful substances. Acceptable packages must be sufficiently difficult for children under the age of five to open, or to obtain a toxic or harmful amount of the substance from the package, but not difficult for the normal adult to use properly. The test protocol for evaluating the child-resistant properties of a closure requires that 200 children be used. They must be about equally divided as to sex, and distributed in age between 42 and 51. months, inclusive. They are dispersed into groups of two each, and placed in comfortable surroundings. A "specially packaged" commodity, which has already been opened and closed ten times or more, is given to each of the paired children with a request for them to open it. For those children unable to open the package after five minutes, a silent, visual demonstration is given for opening the closure. The reclosed package is then given to each child for an additional five minutes. In the second phase of the testing protocol, a panel of 100 adults, aged 18 to 45 years inclusive, 70% of whom are female, is then tested, individually. Each person is given five minutes to open the package. Standard opening instructions, if any, are to be read prior to testing. The percentage effectiveness of all three testing cycles is recorded and compared against specific standards stated in the regulations; e.g. a. Child-resistant effectiveness without demonstration: 85% minimum b. Child-resistant effectiveness with demonstration: 80% minimum. c. Adult-use effectiveness: 90% minimum. The cost of these elaborate testing programs runs between $6,000 and $12,500, depending upon the firm selected. The regulations still permit marketers of hazardous products to sell one can size in ordinary packaging forms, designed for those homes where children are not present, and where the adults may have an infirmity of arthritis, poor eyesight or other problem that limits their ability to remove the child-resistant closure. Aerosol caustic-type oven cleaners, furniture polishes, engine cleaners high in petroleum distillate content and other somewhat hazardous products are often sold in a single package size, thus avoiding the need for onerous special packaging closures. The first aerosol child-resistant closure was introduced by Stem Industries, Inc. in 1969. It was a two- piece assembly of polypropylene. The top segment has an internal thread that was placed over a mate collar held in place by lugs that extended under the rim of the valve cup and allowed it to rotate freely. To open, the collar must be held firmly to keep it from rotating, while the top portion is turned counterclockwise. Like most of its successors, the key to success was that two separate manual operations had to be done, simultaneously, to open the unit. The Stem Industries product looked rather cumbersome, the lower section sometimes impinged the spray, and it was fairly expensive. It was never used to any extent and may now be obsolete. Figure 14. Full Diameter Cover Cap Unique polyethylene full- diameter cover for 202-diameter (42 mm) tinplate cans containing various underarm spray products—marketed in England.
196 The Aerosol Handbook Figure 15. KinderGuard™ Child-resistant actuator. Kinder-Guard is a registered trademark of the Seaquist Valve Company, Cary. IL A unique design for a child-resistant cap was developed by Seaquist Valve Co. about 1972 and is known as the Kinder-Guard™ system. The unit consists of a full- diameter actuator cap, where the actuator has a more- or-less rectangular pad on top. At each side of the actuator are small mounds, or rounded "ears" of plastic which must be spread outward in order to allow the actuator to be depressed. A child's finger is sufficiently narrow that pressing down on the actuator pad will not serve to spread both "ears", although this can be done rather easily by an adult. The closure is the only child resistant system that provides automatic re-engagement of the child resistant position after each use. By doing so, it avoids perhaps the greatest problem with child-resistant hardware: failure of the adult to replace the cap or otherwise reseal the unit after using it. See Figure 15. About 1-976, a major marketer launched an ill-fated product line characterized by a rather unique full-diameter, dome-like, child-resistant actuator cap with a vertical protuberance along one side. To operate, a person inserted the index finger all the way into the tubular cavity formed by the protuberance. At the end was the hidden actuator, which could then be depressed and operated. The child-resistant attribute was satisfied on the basis that a child's finger was simply not long enough to extend up through the hole and reach the sprayhead. In the marketplace the huge plastic dome was said to have had a negative effect upon sales from both an appearence and functional standpoint. Apparently a few people were injured when they had their finger up into the hole at a moment when someone else spontaneously grabbed the unit to take a better look at it. Fingers were sometimes broken in this fashion. The actuator now seems to have disappeared from the market. Excellent child-resistant caps are now supplied by several firms. The 26 active cap models sold by Gilbert Plastics now include 3 child-resistant versions. Imperial Plastics offers 10 active models of cover caps, including two child-resistant sizes. The Knight Engineering and Molding Co. produces 11 caps, of which three are child resistant. The child resistant type locks to the valve cup when attached, and can be removed only by squeezing the sides at designated (serrated) areas while twisting and pulling off. Removal instructions are normally embossed on the top surface of all child resistant caps. Figure 16 is an illustration of the Knight Engineering child resistant cover caps. Specialty Caps In addition to tamperproof and child resistant cover caps, several other specially designed caps are available to help the marketer dispense or use his product more effectively. Powder brush and foam brush caps have Figure 16. Overcaps by Knight Engineering & Molding Company, Arlington Heights, IL (Photo at right) Figure 16 A. Shown below is a line detail of the Knight child resistant overcaps.
Aerosol Cover Caps 197 Figure 17. Modified Summit S-63 Valve and Heavy Duty Actuator/Overcap Used for Tire Inflation been mentioned. A rather unique reversible 202-diameter spray cap is made by the Seaquist Valve Co. for indoor foggers. By removing the cap, turning it upside down and then snapping it down on the valve cup the valve stem is jammed into a centerline hole that ends in a spray orifice. The geometry is such that the stem is depressed far enough to actuate the valve. Other ideas that have been used include the custom gluing of a plastic scrubber pad onto the top of full- diameter caps for hard surface cleaners and paint stripper products. In a similar approach, an emery cloth was attached to the top of caps for paint touch-up products, but the cost was apparently excessive compared with the benefit, and the idea was never marketed. The modified S-63 transfer valve by Summit Packaging Systems Inc. is fitted with a special heavy duty actua- tor/overcap that can be used for tire inflation or for refrigerant transfers. It is illustrated in Figure 17. Precision Valve Corp. (U.S.A.) makes two distinct series of spray domes: the 03-0560/03-0750 Series, and Saturn 03-42 Series. The first of these, developed in the early 1960s, is designed specifically to spray water- based insecticides and air fresheners upward at a 45° angle. Otherwise these products would have to be sprayed by holding the can at an awkward angle to treat the air in the upper third of a room. Because nearly all water-based products must be shaken prior to use to assure a reasonably uniform composition of the spray, the five spray domes are embossed on the top with the words "Shake Before Using." Examples of each series are shown as Figure 18. Figure 18. Precision Valve Actuator Caps (Left: 03-560 Series Right: 03-42 Saturn Series) Decoration Techniques Cover caps can be made in any desired color. As a rule, if the customer desires a particular color he will submit a swatch or coupon to the cap maker, where it is compared against standard color chips in a light box. Plastic prills are provided and molded to that color, with sample caps compared with each other and to the master chip for statistical color control during production. Cap printing is usually done on fully automatic silk- screening equipment, using the customer's camera- ready art. Inks must be formulated to match color specifications. They must resist ultraviolet induced fading and also adhere firmly to the plastic. Copolymer, polypropylene, polyallomer, polyethylenes, K-resin, SAN, ABS and other plastics have all been silkscreened with excellent results. Polyolefins are surface treated to alter the surface and make it more receptive to inks, paints and lacquers. These treatments may include chemical, flame or electronic methods. Hot stamping is sometimes used for special effects. It is a dry process where a flexible foil or other coating is Figure 19. Hemispherical Cover Cap Design The hemispherical plastic cover cap is used on some 202-diameter cans of anti- perspirants and a few other products. The cap is sometimes anodyzed in gold or silver for extra elegance
198 The Aerosol Handbook Murefe tli it'll **!« . pour ii i -1..., fbatfea ■■ •a i hc# ;isa in r \ Figure 20. Customized Cover Caps and Actuator Cap on Aluminum Cans — European Market Figure 21. Ordinary Tinplate Can and Cap, Compared with Brushed Aluminum Can and Cap transferred to the plastic surface by pressure and heat. The impression is made by a metal or silicone die. In the similar heat transfer process preprinted images on the foil are applied to the plastic. This multicolor decoration is a one-step process. Vacuum metalizing and other techniques are available if needed. Figure 22. Blendax Aerosol Toothpaste in Composite Aluminum Tube. Custom Cap, Spout and Base in Shadow-Box, Sold in West Germany Anfr Anth Plaque Zahnpnta DflntifnC€ Metal cover caps may be decorated in a variety of ways. An anodized finish is commonly used for aluminum caps to give a brilliant gold or silvered surface. The process involves an anodic treatment to form an oxide film of controlled properties. The brushed surface often seen on aluminum caps results from a so-called Butler finishing technique, where the metal is micro-scored with a myriad of more-or-less parallel lines, using rotating wire brushes or cloth wheels with applied abrasives. (This technique is also used for the finishing of aluminum aerosol cans in Europe, but is not yet done in the U.S.A.) Aluminum caps are also treated by matte dipping, electroplating and vacuum metalizing. In the last process a very thin film of metal (generally aluminum) is deposited on the substrate by means of evaporation under high vacuum. After metalizing, a top coat of clear or colored lacquer is applied to protect the delicate metal film. The process can be applied to most plastics and to glass. Aluminum and enameled steel caps may be decorated by silkscreen printing. Steel discs are silkscreened or enameled prior to deep drawing into cover caps. The printed matter may become slightly wavy due to the uneven stretching of the metal as it is worked, but this is almost never a cause for concern.
AEROSOL FLAMMABILITY 199 7 The flammability of aerosol products has always been an issue of primary importance to the industry. In the U.S.A., starting about 1977, it assumed even greater dimensions as the non-flammable chlorofluoro- carbdns (CFCs) had to be virtually abandoned due to federal regulations, and were largely replaced with intensely flammable hydrocarbon gas liquids. Finally, in 1980, the Factory Mutual Research & Engineering Corp., owned and operated by four major insurance companies, conducted a series of large-scale fire tests using palletloads of aerosols and concluded that most warehouses did not have sufficient sprinkler-system protection to safely store a majority of aerosol products. An overview assessment suggests that the flammability of aerosols is one of the most pressing and important issues that the industry must address during the 1980s. In the U.S.A., the earliest aerosols were the insecticide "bombs", developed in 1943 by Lyle Goodhue and William Sullivan of the U.S. Department of Agriculture. They were formulated with 85 to 90% P-12 in order to obtain a very fine particle size for maximum killing power. Because of the very high CFC content they were non-flammable under any reasonable condition of use. When the first disposable-can aerosols came along, about 1947, pressure limitations imposed by the Interstate Commerce Commission (ICC) required die use of at least 80% CFC propellents to produce a space- type spray. As a result these insecticides and room deodorants were also considered non-flammable. But, by the end of the 1940s, several other products had entered the market. They included hair sprays and paints, products designed to produce a somewhat heavier, coating-type spray. They used only 60 to 65 % CFC propellents. In early 1950, a fire chief in Buffalo, NY demonstrated the flammability of a hair spray by lighting the spray plume with a match during a lecture on product safety. The experiment got out of hand
200 The Aerosol Handbook when a curtain behind the podium ignited, to the supreme embarrassment of the speaker and to the delight of several reporters in the audience. The resulting publicity brought the aerosol industry face to face with the the flammability issue. Within a few months a Flammability Committee was formed within the new Aerosol Division of CSMA. Its purpose was to develop test methods and guidelines for aerosol flammability. They worked closely with Dr. John McKenna of the Bureau of Explosives, of the American Association of Railroads, and with Dr. "Bus" Fulton of the USDA, finally developing three mutually complementary test methods, specific for aerosols. In their capacity as an advisory technical body to the Interstate Commerce Commission, the Bureau of Explosives recommended that test methods and definitions be added to the Commission's official tariff, which described regulations for the interstate transportation of dangerous goods. This was done in 1952. As succinctly as possible, the three methods may be described as follows: a. The Flame Propagation Test An aerosol is "Flammable" if it produces a flame elongation of 18" (457 mm) or greater when sprayed through the top third of a candle flame from a distance of 6 "(152 mm). b. The Closed Drum Test An aerosol is "Flammable" if, when sprayed through a 1" (25 mm) port into a closed, horizontal 55 gallon (200 liter) metal drum with a lighted candle at the bottom, a "whoof' or large, rapid burning of the vapor/air mixture occurs within 60 seconds. c. The Open Drum Test An aerosol is "Flammable" if, when sprayed at a candle flame within a horizontal, open-end 55 gallon (200 liter) metal drum from a distance of about 36 " (914 mm), a gross enlargement of the flame occurs. At first the "Flammable" aerosols were not permitted in interstate shipment, but as more and more viable products of this type were developed in various laboratories, the need to ship them became more acute, and chemists started to use low delivery rate and vapor- tap valves in order to control the sprays so that they could pass the tests. In 1954 the bug killer (75% petroleum distillate and toxicants,plus 25% P-12) was developed, but even with the most propitious valve adjustments it easily failed all three tests. Following a special industry meeting in Chicago, a group approached the ICC about mid-1954 and was able to persuade them to allow such products in interstate commerce, provided the flash point, by a low- temperature modification of the standard Tagliabue Open Cup method, was 20°F ( - 6.7°C) or higher. The outer shipping cases also had to carry a red, diamond- shaped "Flammable" product label. With this relaxation in the regulations, large numbers of red-labeled aerosols began to flow through channels of trade. The 20°F (-6.7°C) temperature selection was actually designed to permit the use of acetone and solvents of higher flash point, but to prohibit the interstate transportation of diethyl ether engine starting fluids. Hydrocarbon propellents were virtually unknown in 1954, so the flash point proviso had almost no limiting effect on the industry at that time. But, in 1955 isobutane entered the aerosol scene, being first used in "Bon Ami" window cleaner at a level of 3.0%, and in conjunction with the mechanical break-up valve, first developed by Walter C. Beard, Jr. of Risdon Manufacturing Co. during the preceding year. The flash point test could not be meaningfully conducted on this product, because the large amount of water in the concentrate froze when the aerosol was equilibrated to -20°F (-28.8°C) prior to opening the unit. In any event, running this test was unnecessary, since the standard triad of flammability tests were all passed by the product. This development set the stage for the introduction of similar products: aerosol starch in 1955, aerosol multi-purpose cleaners in 1956, aerosol oven cleaners in 1957, and so forth, all with about 2 to 5.5% of hydrocarbon propellent and large amounts of water. Blends of hydrocarbons and CFCs were then used,not only for hair sprays, but for penetrating oils, personal deodorants and a number of other products. They could be purchased directly from the CFC producers. Two of the more common were identified as Propellent A (45% P-12, 45% P-ll and 10% isobutane) and Varisol IV Propellent (52.4% P-12, 37.0% P-ll and 10.6% isobutane — to which various amounts of methylene chloride were sometimes added as the fourth component during the filling process). During 1961 S.C.Johnson & Son, Inc., introduced their lines of "Raid" insecticides and "Glade" air fresheners in a water-based form. A number of similar formulations were launched by other marketers during
Aerosol Flammability 201 1962 to 1964 as a response, since the economic advantage was so overwhelming. Typically, these formulations had 28 to 34% hydrocarbon (A-31 to A-46), less than 10% of oil-based concentrate and the balance of water, plus traces of emulsifier and corrosion inhibitors). They were still non-flammable, although just barely so in many cases. They owed this accomplishment to the use of low delivery rate valves having vapor-tap features. The success of these new formulations sensitized the rest of the industry to the fact that valve modifications represented an important way to get around the three flammability tests and market products as "not flammable", which actually contained a rather high level of flammable ingredients. The Federal Hazardous Substances Act of 1960 was passed by Congress about this time, and the FDA was charged with the administration requirements. On Aug. 14, 1961 they published their Final Order (26 Federal Register 191) covering definitions and procedural and interpretative regulations. Part 191.1(1)(1 & 2) promulgated the first federal definitions ever established specifically for "Flammable" and "Extremely Flammable" aerosols: Flammable Contents. Contents of self-pressurized containers are "flammable" if when tested by the method described in pph. 191.15 a flame projection exceeding 18 inches is obtained at full valve opening or a flashback (a flame extending back to the dispenser) is obtained at any degree of valve opening. Extremely Flammable Contents. Contents of self- pressurized containers are "extremely flammable" if when tested by the method described in pph. 191.15, flashback (a flame extending back to the dispenser) is obtained at any degree of valve opening and the flashpoint, when tested by the method described in pph. 191.16, is less than 20°F. The scope of the Act was limited to household products. It did not cover economic poisons, foods, drugs, cosmetics or fuels. On the other hand, the industry quickly used the results of these tests as a guide for the precautionary labeling of all aerosol products. While the safety of the consumer was the central concern, another factor was that marketers could protect themselves more adequately in product liability suits if they could state that their products were labeled in accordance with government requirements for similar products, in the absence of any regulations specifically for the product in question. This concept is still being used in the defense of suits brought against personal products, since the FDA has yet to establish any labeling regulations relating to the flammability of aerosol foods, drugs or cosmetics. If an aerosol product falling under the FHSA is classified as "Flammable", the regulations require the statement "WARNING — Flammable" (or "CAUTION — Flammable", optionally) to appear on the principal panel. The signal word must be in 18 point type, while the statement of hazard must be in 12 point type. An exception, down to 6 point type, may be made for small containers. Supplemental statements are also required. The minimum would be: "Keep away from heat, sparks or open flame. Use with adequate ventilation." These words may be on the front, back or side panels, in type size of normally 10 point. If they do not appear along with the signal word and statement of hazard on the principal panel, then some statement such as ''See back panel for additional cautions.'' must appear below these words. Similarly, if a product is classed as "Extremely Flammable", the regulations require the statement "DANGER — Extremely Flammable" to appear on the principal display panel. All the other provisos given in the preceding paragraph then apply also. When the Consumer Product Safety Commission (CPSC) was formed in 1972, the Congress declared that they should assume the administration of the regulations under the FHSA. Accordingly, in 1973 the regulations were revised and transferred [CPSC Ch. 2, C, 1500(c)(6)(v & vi)]. The revisions were minor and did not affect aerosol flammability sections. During the mid-1960s the ICC, now a segment of the newly created Department of Transportation, established that the excellent safety record in the shipping of aerosols warranted a benevolent relaxation in their regulations. Three separate things were dope: a. The red, diamond-shaped "Flammable — Danger" label could be removed from the outer shipping cases of all metal aerosol units, up to can sizes of 35 cu. in. (573.5 ml) overflow capacity. b Flammable aerosols in metal container were permitted for shipment even if the contents had a TOC flash point below 20°F (-6.7°C). c. The Open Drum Test was abandoned, since it had little or no practical significance.
202 The Aerosol Handbook The concessions had a stimulating effect upon the industry. After a time it became obvious that the safe shipping record was still being maintained, and in 1976 the DOT acted to substantially revise the entire fabric of their shipping regulations. Over 99.8% of all aerosols were presumed to fall under the new ' 'Consumer Commodity ORM-D" classification, which applied to all aerosol packages weighing under 29.5 kg (65 lbs) and where the product was either a consumer commodity or an industrial/institutional item for which there was a practical consumer counterpart sold domestically. The other 0.2% or less were I/I items for which there was no consumer equivalent, such as metal lay-out dyes and refrigeration system leak detectors. Under ORM-D, aerosols could be shipped without restraint as to flam- mability status or metal container size, up to the 50 cu. in. (819 ml) limit. Strictly I/I type aerosols still had to be marked with red "Flammable" labels if the dispenser size was over 35 cu. in. (573.5 ml). The ORM-D term meant "Otherwise Regulated Material — Class D" and was applied only to ground transportation. For air transport the related term "Consumer Commodity ORM-D-AIR" was used, and a few additional regulations also came into play. On a practical basis, despite the permissive DOT position, those wishing to transport flammable aerosols by air will find that commercial airlines have very strict corporate or union-originated rules which often make it impossible, impractical or extremely expensive to make such shipments. The shipment of a few pounds of flammable aerosols between the U.S.A. and Europe by a freight-carrying (non-passenger) airplane could easily cost over $100 in 1982. In the special situation of glass, plastic-coated glass and plastic aerosol containers, the DOT have elected not to relax their original regulations, since they were rather concerned about the possible hazardous effects of product breakage, during an accident or as the result of rough handling. In general, these aerosols are not permitted in interstate shipment if their contents are "Flammable'' and have a modified TOC flash point of 20°F (-6.7°C) or less, provided the dispenser has a capacity of over 4 fl. oz. (118.2 ml). Aerosols of less than 4fl.oz.(118.2 ml) capacity are exempted from pressure limits, flammability considerations and all other DOT regulations, provided the contents are non-poisonous. With the virtual demise of CFC propellents in the U.S.A. after 1977, the glass aerosol segment of the industry suffered a particular problem in that many of their standard size bottles were over the 4 fl. oz. (118.2 ml) limit. They could not be shipped interstate or abroad if they contained formulations utilizing a hydrocarbon propellent and were classed as "Flammable". A few products, such as foams, quick-breaking foams and other high water content formulas, could be propelled with hydrocarbons and still remain non-flammable, but probably 98% of all large size glass, plastic- coated glass and plastic aerosols were banned from interstate shipment on the basis of flammability. About 1980 the Wheaton Aerosols Company (the sole U.S.A. producer of plastic-coated glass aerosols) decided to meet this restriction head on. After exhaustive testing they were able to prove that their popular nominal 4 fl. oz. Boston Round aerosol bottle, with Lamisol plastic tri-layer coating, was extremely resistant to breakage, and that even if it did break, the rate of product release was either nil or negligible for a long time thereafter. This bottle has a capacity of 4.67 fl. oz. (138.0 ml). After a review of the data the DOT authorized a special exemption for this particular coated botde. Any customer using the bottle is automatically covered by the exemption. During the 1970s the U.S. Environmental Protection Agency (EPA) also developed flammability regulations. The first phase came about as a public notice, under the aegis of the Federal Insecticide, Fungicide and Roden- ticide Act (FIFRA). It was little more than a jumble of words, ambiguous and impossible to interpret with confidence. But then, about mid-1975, revised definitions and labeling provisions were promulgated in the form of revisions to the Federal Environmental Pest Control Act regulations (FEPCA). Under FEPCA, if an aerosol concentrate has a modified TOC flash point of 20°F (-6.7°C) or less and the finished aerosol has a flashback (a flame extending back to the dispenser) at any degree of valve opening, then a label statement is required which reads, "Extremely Flammable. Contents under pressure. Keep away from fire, sparks and heated surfaces. Do not puncture or incinerate container. Exposure to temperatures above 130°F may cause bursting." (130°F equals 54.4°C). The precautions may be placed on the side or back label panel if desired. Similarly, if the aerosol concentrate has a modified TOC flash point above 20°F (-6.7°C) but not greater than 80°F (26.7°C), or if the flame extension is greater than 18" (457 mm) when the finished product is
Aerosol Flammability 203 sprayed through the top third of a flame from a distance of 6" (152 mm), then a label warning statement is required which reads, "Flammable. Contents under pressure. Keep away from heat, sparks and open flame. Do not puncture or incinerate container. Exposure to temperatures above 130°F may cause bursting." (130°F equals 54.4°C.) In contrast, for all other pesticides a warning label statement is required which reads, "Contents under pressure. Do not use or store near heat or open flame. Do not puncture or incinerate container. Exposure to temperatures above 130°F may cause bursting." (130°F equals 54.4°C.) These required pesticide precautionary statements normally appear on the side or back panels, and type size is determined by that of the other printed matter, available space and other factors. But in no event shall the type size be smaller or less distinct or less contrasted with the background than that of the other printed material. In at least one instance, a pesticide was seized by the EPA because the precautionary language was uniquely inscribed in dark blue over a metallic blue background, making it excessively hard to read. The marketer agreed to paper label the unsold dispensers, changing the disputed area of the metallic blue color to white. Aerosol Flammability Regulations in Japan In Japan all aerosols are produced, labeled and sold under the jurisdiction of the High Pressure Gas Control Law of 1951 but broad exemptions are provided when the products conform to later Ordinances and Notifications of the Minister of International Trade and Industry (MITI). Typical general requirements for both flammable and non-flammable products are as follows: a. The amount of propellent is limited to 500 g per container. b. The product volume is limited to 90v % of the container at 95°F (35°C). c. Containers with a capacity over 100 ml must be cylindrical, with an inner diameter not over 3.15" (80 mm) and made of steel or light metals. An exception is containers for P-12, which are limited to a bore of 3.00 " (76 mm). •While these requirements are current in 1982, the AIAJ advises they are under extensive review and may be completely revised. Firms wishing to determine current regulations after 1982 should contact the AIJA or the Japanese Embassy for information. d. Metal containers shall not have a thickness below 0.008465 " (9.215 mm). Note: this corresponds to the minimum thickness of 81-lb baseweight plate, as made in the U.S.A. e. The maximum pressure for liquefied propellents or blends is 114 psig at 95°F (8 kg/cm2 or 786 kPa at 35°C), and that for compressed gases (as CO2) is 143 psig at 95°F (10 kg/cm2 or 986 kPa at 35°C). f. Metal containers shall not deform irreversibly at pressures less than 186 psig (13 kg/cm2 or 1.282 MPa). g. Metal containers shall not burst at pressures less than 214 psig (15 kg/cm2 or 1.476 MPa). h. Metal containers shall not exhibit gross leakage below 118.4°F(48°C). i. Insecticides are limited to 250 g of contents and may contain up to 56% of methylene chloride. j. Formulations must be non-toxic and non- corrosive to the dispenser. k. Glass aerosols are limited to 100 ml capacity and must be plastic coated. 1. The name or symbol of the manufacturer, the production lot number, and the precautions of use must be listed on the label of aerosols having a capacity of over 1.00 fl. oz. (30 ml). m.All aerosols must be hot-tanked so that the contents temperature is raised to within the range of 115 to 122°F (46 to 50°C), but no higher. Aerosol cosmetic products specified in the Pharmaceutical Law are permitted to contain up to 10% flammable propellents, but only if the water content is over 40% and the product is dispensed as a foam or paste. Activities are now being carried out under the aegis of the Aerosol Industry Association of Japan (AIAJ) to have this rule (Notification No. 291 of MITI, 1974) relaxed in order to permit hydrocarbons and dimethyl ether to be used more adequately for such products. The precautionary labeling of aerosol products according to five levels of relative flammability is regulated under Notification No. 557 of MITI, 1968. Flammability is assessed on the basis of two tests: the Flame Projection Test (similar to the U.S.A. method, except that a gas burner must be used) and a modified Closed Drum Test. The Japanese "explosion chamber" is a horizontal cylinder of 11.9 to 14.5 gallon (45 to 55 liter) capacity, equipped with a fan and a sparking or
204 The Aerosol Handbook ignition plug. A loose-fitting lid closes off one end of the chamber and the other end carries a small port for spraying the aerosol into the drum. Spraying is done for one second at a time, with two seconds in between. When a "poof or mild explosion occurs, the weight loss from the aerosol can is measured and the Explosive Concentration (Ec) is measured as the weight loss in grams divided by the volume of the chamber in liters. The required precautionary labeling consistant with the results of the two tests is shown in Table I. Experiments in the U.S.A have shown that the results of the Japanese Closed Drum Test can be duplicated with the U.S.A. 55 gallon (200 liter) regular Closed Drum device, provided a spark plug is used instead of the conventional candle flame, since the flame actually burns up a portion of the flammable vapor during the test, making the results apparently less critical. Table I Flammable Aerosol Classifications and Precautionary Labeling in Japan Test Result Classification Precautions Do not keep at temperatures over 40°C Do not throw into fire after use. As above. Ec =over 3 g/1 and F.P. =0"max. Non-flammable Ec =Over 1 g/1 and F.P. =2"(50mm) max. Not easily flammable Ec =Over 0.25 g/1 Do not direct toward a flame. F.P. = 10" (250 mm) max. Do not use large amounts near a Slightly fire, flammable Do not keep at temperatures over 40°C Do not throw into fire after use. Ec = Over 0.13 g/1 and Do not apply toward the human F.P. = 17.7" (450mm) max. body. Moderately Do not use near fire, flammable Do not use large amounts where a flame is also present in the room. Do not keep at temperatures over 40°C Do not throw into fire after use. Ec = Below 0.13 g/1 or Do not apply toward the human F.P. =over 17.7" (450mm) body. Highly Do not use near fire or in houses flammable where flames are also present. Do not store at temperatures over 40°C Do not throw into fire after use. Aerosol Flammability Regulations in Europe In Europe, aerosols are produced and sold under the laws of individual countries, but may be transported or exported under various international regulations. Typical general regulations which apply to both flammable and non-flammable aerosols are as follows: a. European Economic Community (EEC) regulations apply to metal cans from 50 to 1000 ml capacity, to plastic coated or otherwise permanently protected glass containers from 50 to 220 ml capacity and to frangible glass or plastic containers from 50 to 150 ml capacity. Dispensers larger than these sizes are not permitted. b. The product volume is limited to 95v% of the container at 122°F (50°C) if the can has a deformable concave base; otherwise it is 90v%. For aerosols normally stored in cars this may decrease to 85v% in some countries. The dispenser should not become liquid filled at temperatures less than 158°F (70°C). c. Containers of metal having an outside diameter of 1.575" (40 mm) or greater must have a concave base. (U.K.) d. For containers having products where the pressure is less than 97.2 psig at 122°F (670 kPa at 50°C) the test pressure resistance must be at least 145 psig (1.000 MPa). For containers holding products with pressures higher than that, the test pressure resistance must be at least 50% higher than the pressure at 122°F (50°C) for liquefied propellents and 33.3% higher than the pressure at 122°F (50°C) for compressed gases. (EEC — 1975) e. The maximum pressure for liquefied propellent formulas is 116 psig, and for compressed gas formulas is 130.5 psig at 122°F (800 and 900 kPa resp. at 50°C). (EEC - 1975) f. Aerosols must be hot-tanked so that the contents temperature rises to at least 122°F (50°C), or the pressure becomes equivalent to the equilibrium pressure of the contents at that temperature. g. Contents are declared as average volume, expressed only in metric units. An exception is made for U.K. cosmetics, which presently may be labeled in both metric and imperial units of weight and/or volume. This will probably change soon.
Aerosol Flammability 205 Around 1966 the Federation of European Aerosol Associations (FEA) settled upon a definition of flammability based upon the weight and percentage of combustible components in the aerosol formulation. Specifically, they recommended that aerosols containing more than 45% by weight, or more than 250 g of flammable contents should be labeled ' 'Flammable. Do not use near fire or flame.'' The flammable ingredients (interchangeably called both inflammable and combustible in Europe) were those having a flash point of less than 212°F (100°C), using the Tagliabue, Abel, Abel-Pensky or Luchaire-Finances closed cup testers. Shortly afterward the Reglement International Con- cernant le Transport de Merchandise Dangereuses par Chemin de Fer (RID) adopted the definition for purposes of railroad transportation in Europe. They allowed both types of aerosols without restraint, even for railroad express shipments. About 1969 the Accord Europeen Relatif le Transport International Dangereuses par Route (ADR) also adopted the definition for purposes of truck transportation in Europe. Aerosols were grouped into the danger category, Class 2, Part E, and differentiated as follows: a. Non-flammable aerosols. b. Flammable aerosols. i. Those with less than 45% by weight of flammable material. ii. Those with more than 45% by weight of flammable material. Their regulations (No. 2208, 2209 and 2210) specify the conditions required for transport, such as container markings, fill amount and so forth. They are in harmony with the latest revisions of the Technical Regulations for Pressurized Gases (TRG 300 — West Germany) and other national and international regulations. At about the same time the International Maritime Consultative Organization (IMCO), developed regulations for shipping purposes, now known as the International Maritime Dangerous Goods Code (IMDG), which is more complicated than the RID or ADR regulations, but where the percentage of flammable ingredients is still used for the classification of aerosols. Four classes are used, according to relative flammability: a. Class 2: (Gases) Aerosols containing more than 10% flammable gases. b. Class 3: (Flammable Liquids) Aerosols containing either more than 45% flammable liquids and no flammable gases, or those containing more than 35% flammable liquid in the presence of flammable gases, c. Class 9: (Various Dangerous Materials) Aerosols containing no flammable gases but more than 10% of flammable liquids. The International Air Transport Association (LATA) publishes air transport regulations. So far they have adhered to the U.S.A. and Canadian methods of defining flammability on the basis of the properties of the aerosol, rather than the composition. However, if aerosols contain flammable gases or liquids, a prescribed red flame-symbol label must be affixed to the outer case. Conversely, aerosols containing nonflammable gases must carry a green label on the shipper. Around 1968 a concerted effort was made, led by Dr. Werner Lessenich in Europe and the author in the U.S.A., to harmonize the divergent approaches to aerosol flammability in these two areas, which at that time accounted for about 86% of the world's aerosol production. Some 350 cans were tested for both flammable content and flammability in Europe and about 250 cans were evaluated in the same way in the U.S.A. Using the European 45% flammables dividing point, there was a 74% agreement (non-flammable by test = below 45% flammables, and flammable by test = above 45% flammables), with an additional 23% classed as non-flammable by test but flammable in Europe, and 3% flammable by test, although having less than 45% flammable ingredients. By moving the dividing point to 55 % flammables the results per 85 %, 10% and 5%, resp. and by adjusting to 56.5% flammables the results became 87%, 8% and 5%, resp. This last result was the one that showed the greatest agreement possible between approaches. A number of U.S.A. aerosols were non-flammable according to the flammability tests, yet they contained well over 45% flammable ingredients. This was due to the use of low-delivery rate valves, based upon either small orifice or vapor-tap features, or sometimes the addition of methylene chloride as a flame suppressant in the flame projection test. Neither of these expediencies were much used in Europe at the time. Now they are. In fact, the heavy usage of methylene chloride as a vapor pressure depressant, flame depressant and solvent has engendered numerous regulations there. For example, in solvents, paints, varnishes and glues, if more than 10% is used, the label must have a St.
206 The Aerosol Handbook Andrews (diagonal) cross, plus the phrases "Harmful vapor. Avoid contact with the skin, eyes and clothing. In pesticides, if more than 20% is used the label must state "Contains % methylene chloride"; but in cosmetics up to 35% is permitted and no warning phrases or symbols are required. A provisional decision was made by the FEA that they would try to persuade the RID and ADR organizations to accept as "Flammable" those aerosols which either contained 55% or more of flammable substances or were flammable according to the test methods used by the ICC in the U.S.A. But, it was predicated on approval of the same criteria by the ICC. The proposal was presented to the Flammability Committee, Aerosol Division, CSMA where it met with strong minority resistance. Subsequently, it was discussed informally with Mr. Roberts, the Secretary to the ICC commissioners, who turned it down, since he did not like any "either/or" regulations. As a result, the proposal failed and the two leading producers, Europe and North America, are now unalterably committed to their different approaches toward the defini- Table II tion of aerosol flammability. At least to date, the dichotomy has not had any significant ill-effects on the industry. During the past several years, European aerosols have inexorably moved toward compositions containing higher levels of flammable ingredients. This has been due not only to bans, threats of bans, 30% voluntary reductions and other sanctions placed upon the use of CFCs due to the CFC/ozone controversy, but also because alternate propellents such as the hydrocarbons and dimethyl ether (DME) are much more economical. The transition can be seen in Table II which shows large increases in the flammable content of aerosols in both the U.S.A. and the U.K. during the period 1976 through 1981. It is anticipated that, during the 1980s, the flammable content of virtually all anhydrous or low-water content European aerosols will rise well above the 45 % mark, causing about 75% of the overall production to be considered "Flammable". The British have recognized that the U.S.A., IMDG and other entities have established two or more levels of Flammable Contents of Aerosols Produced in the U.S.A. and the U.K. (1976 and 1981) Country Year Product Category Production (Millions) 0-20 Per Cent Flammable Content 20-40 40-60 60-80 80-100 U.S.A. 1976 Antiperspirant Personal Deod. Hair Sprays Other Personal Products Household Products Industrial Products Food Products Lighter Fluids 298 107 289 287 1,069 94 151 252 98 0 0 55 26 30 95 0 2 5 3 1 21 10 4 0 0 70 96 27 3 50 1 0 0 25 1 17 5 5 0 0 0 0 0 0 44 10 0 100 U.K. 1976 Personal Products Household Products Industrial Products Lighter Refills 242 243 13 22 22 21 58 0 42 78 7 0 35 1 20 0 1 0 0 0 15 0 0 100 U.S.A. 1981 Antiperspirant Personal Deod. Hair Sprays Other Personal Products Household Products Industrial Products Food Products Lighter Fluids 180 55 252 260 1,090 177 147 280 0 0 0 74 23 10 71 0 0 0 0 1 20 2 0 0 98 100 96 23 52 85 23 100 U.K. (Est.) 1981 Personal Products Household Products Industrial Products Lighter Refills 207 232 19 27 10 23 49 0 30 59 6 0 40 10 21 0 7 13 4 4 14 10 0 100
Aerosol Flammability 207 flammable hazard, and now they have done this as well. Aerosols have "Flammable Contents" (as before) if they contain 45% by weight or more than 250 g of substances having a closed cup flashpoint of 212°F (100°C) or less. In a later regulation (the Highly Flammable Liquids and Liquefied Petroleum Gases Regulations of 1972, S.I. 1972/917 aerosols with a total content of 500 ml or more and with a highly flammable content of more than 45 % by weight or more than 250 g are regarded as having "Highly Flammable Contents". Highly flammable ingredients are here defined as either liquefied flammable gases or liquids having a flash point of less than 90°F (32°C). During about 1978 Flammability Committees were formed within the FEA, BAMA and other associations for the purpose of developing various test methods, including counterparts of the Flame Projection Test and Closed Drum Test as used in the U.S.A. Modifications of these tests were considered also. One involved a determination of maximum ignition distance, by bringing a lighted candle progressively closer to the dispenser and actuating the valve until ignition occurred. Figure 1 provides the results of testing a variety of ethanol/pro- pellent hair spray prototypes by this method. The delivery rate is assumed to be about 0.4 g/sec at 77° (25°C). The coarser sprays were the most flammable, according to the test results. Other approaches involved a calculation of the weighted average heat of combustion in BTU/kcal/g) for the contents of filled cans, and a method for determining the relative flammability of a sprayed surface. Combinations of flammability methods have also been suggested. Perhaps the most notable in Europe was that presented by Vitat, Viel and Pichard of Rhone Poulenc Industries — France — at the FEA meeting in Brussels, March 26, 1980. It involved the use of four tests (%flammables content, flame extension, lower flammability limit and flashpoint/firepoint) to develop twenty numerical results per product. By complex statistical methods, involving principal components factor analysis, discriminant factor analysis and multivariate regression, products can be assigned a flammability index number from 0 to 100. The high flammability range extends from 71 to over 100. The FEA committees have not acted on the proposal during the two years since it was first presented, perhaps due to the complexity of the statistical treatment. Figure 1. Flame Consequences of Spraying Diagram illustrating flame consequences of spraying hair sprays various distances to a candle ignition source. Chart through the courtesy of the Aerosol Industry Association of Japan. 700 r VOLUME % hano 60 50 40 60 50 60 50 99+ 1 Propellent 40 A-51 50 A-51 60 A-51 40 A-73 50 A-73 40 P-12/11 30:70 50 P-12/11 30:70 1- Nitrogen DISTANCE TO CANDLE FLAME (mm) (Flame position - axis to fepray cone.)
208 The Aerosol Handbook lAl/y/79 fXT\ Co) GB/116/12345 Figure 2. UN Certification Marking Explanatory Notes: 1A1 UN package number Y Suitable for Group II and III (Medium and Minor danger) 79 Year of Manufacture GB Made in Great Britain 116 Identification number of testing laboratory 12345 Test serial number The standard European method for flame projection involves the use of a sophisticated tester developed in 1965 by Dr. Willi Roth of Switzerland. The effective flame length is established by mounting vertical cotton threads 10 to 20 mm apart, down the path of the aerosol flame plume. The last cotton thread to burn in two indicates the effective flame length. Since the equipment is quite costly and correspondingly unavailable to most laboratories, testers more like those in the U.S.A. have been used, with flame length measured visually against a rule. There has been some discussion about modifying the basic flame projection test so that cans would be sprayed at the candle flame from various positions (upright, inverted and side) and from various distances. The testing of full, half-full and essentially empty cans was also suggested, as well as the use of various temperatures. It was felt that such added complexities, while they might more closely relate to the divergencies of consumer use, would increase the testing time perhaps tenfold. If the most flammable results were used as the basis for definition, then the expanded test could have the negative effect of making more aerosol products flammable than would be the case with the regular procedure. The results of 4 to 6 laboratories were used to compile the data in Table III, which shows the results of flam- inability testing of various European aerosol cosmetics. Aerosol Flammability Recommendations by the UN In general, the recommendations by the United Nations (UN) are in close harmony with those of various international conventions, such as RID, ADR, Table III Typical Flammability Test Results - Europe (Flame Projection and Closed Drum Test Methods) Test Product Flame Projection Test* Closed Drum Test* %-Flammable Pressure; Spray Rate Density Testers who Ignition (psig; 68°F) (g/sec - 68°F) (g/ml) Shortest Longest Flashback had ignition. time(s) %(w/w) %(v/v) Hair spray using 29 0.7 0.972 dimethyl ether Hair spray using 41 1.0 1.04 chlorofluorocarbon Hair spray using 35 0.8 0.912 butane/propane/CFC Hair spray using 88 0.65 0.995 carbon dioxide Hair spray using methylene chloride 40 0.60 0.768 and butane/propane Personal deodorant 58 0.6 0.791 using dimethyl ether Personal deodorant 19 0.6 0.951 using chlorofluorocar. Personal deodorant using butane/propane 45 0.5 0.786 and chlorofluorocarbon 10' 13' 14" 9" 9" 13" 19" 6" 9" 11" 1" 2" 0 to 6" 0 to 3" 2 to 6" 0 to 6" 0 to 2" 60% 51 to 70 45 40% 50 to 51 38 67% 31 to 78 — 50% 42 to 56 42 100% 26 to 60 43 60% 54 to 81 65 66 25% 83 57 79 60% 34 to 57 70 •Testers used various drum closures. The slit polyethylene closure gave fastest results. **Bunsen burners, candles and a spark device were used as ignition sources. All gave equivalent results. Courtesy: FEA (CTA Flammability Committee), 1981.
Aerosol Flammability 209 IMCO and IATA. Flammable aerosols are in Classes 2, 3 and 9, as in the IMDG code. They must carry the now familiar 100 mm x 100 mm red, diamond-shaped "flame" label on the outer shipper and meet package performance tests, such as drop, stacking and leakage tests. "Permitted packages" may carry the UN certification mark shown in Figure 2 along with required specific data. Aerosol Flammability Regulations in Australia Voluntary standards for aerosols are provided in Australian Standard AS 2278-1979 and are the same for non-flammable, flammable and highly flammable formulations: a. Containers must have at least 10v% head space at 131°F (55°C) and must not become liquid filled at less than 185°F (85°C). b. Maximum allowable pressures are as follows: i. Low pressure container: 140.7 psig at 131°F (970 kPa at 55°C). ii. Intermediate presssure container: 159.5 psig at 131°F (1.100 MPaat 55°C). High pressure container: 179.8 psig at 131°F(1.240MPaat55°C). Soldered side seam container: 100.0 psig at 100.4°F (690 kPa at 38°C). v. Tire inflator products at 185°F (85°) must not exceed the bursting pressure of the container. c. All containers must be hot-tanked unless the contents are adversely affected. The sole measure of flammability is the Flame Extension Test; AS 2278-1979 Section 2.4.3(a & b). Using an apparatus similar to that in Figure 3, aerosols are defined as "Flammable'' if the average length of the flame is between 7.87-17.72" (200-450 mm) and "Highly Flammable" if the average length of the flame is over 17.72" (450 mm), or if it burns back to the actuator, or if it continues to burn when the test flame is extinguished. Aside from relevant statutory requirements, where appropriate, each aerosol container must be prominently marked "Flammable" or "Highly Flammable" and must carry the appropriate symbol as specified in AS 1216 Part 1. While the Australian Standard is not mandatory, the State of New South Wales has passed legislation where in. IV. Adjustable test flnme Figure 3. Australian Flame Projection Test Unit the Flame Extension Test is used to determine flammability, which in turn legislates specific labeling. The commercial importance of the State has thus, in effect, created a regulation for almost all products made in Australia. With the dramatic increase in the use of hydrocarbon propellents in recent years, the industry has been talking with the authorities about potential problems in the storage and transport areas, and the use of definitions in the International Maritime Dangerous Goods (IMDG) code are being considered for outer shipper designations and handling procedures. Figure 4. Canadian Flame Projection Tester A. Recommended remote can actuating device B. n-Butane gas flame: 150 mm from actuator button C. First frame for cheesecloth: 150 mm from flame D. Second frame for cheesecloth: 450 mm from flame
210 The Aerosol Handbook Aerosol Flammability Regulations in Canada In general, the aerosol regulations and industry accords in Canada are quite similar to those in the U.S.A., but this does not extend to flammability. During early 1979 a new modification of the Flame Projection Test was agreed upon between government officials and an industry committee containing representatives of the Canadian Cosmetic, Toiletry and Fragrance Association (CCTFA), Canadian Manufacturers of Chemical Specialities Association (CMCSA) and the Canadian Paint Manufacturers Association (CPMA). The apparatus is illustrated in Figure 4. The device carries a holder to fix the aerosol can and spray, plus a recommended remote actuator, such as a caliper type, side pull bicycle hand brake. A burner tube with 0.050" (1.2 mm) gas orifice is positioned to terminate 2 " (50 mm) below the aerosol orifice and is then adjusted to give a 2 " (50 mm) flame height. If ignition fails to occur, the position is changed to 4" (100 mm) below the dispenser orifice and the flame adjusted to give a 4.7 " (120 mm) height. The burner is located 6 " (150 mm) from the orifice of the dispenser. It is attached to a supply of n-butane via a regulator which governs the flame height. Two vertically adjustable support frames are positioned 6 " (150 mm) and 18 " (450 mm) from the burner. They each have an open space 13.78 " (350 mm) wide by 17.71" (450 mm) high. During the test they are used to support cheesecloth fabric, which is clipped on and Table IV Required Aerosol Labeling as a Result of Flame Projection Test Flame Projection/ Longueur de la flamme Less than 15 cm/ mollis de 15 cm 15 cm or more but less than 45 cm/ 15 cm et plus nwis oolns de 45 cm 45 cm or more/ 45 cm et plus Flashback to the container/ Ret our de flamme jusqu'au contenant Symbol/ Symbole W <§> ® @ Signal Word/ Mot-indicateur Caution/ Attention Warning/ Avertlssement Danger/ Danger Danger/ Danger Nature of Primary Hazard/ Nature de risque primal re Flammable/ Inflammable Flammable/ Inflammable Extremely flammable/ Ext rSmement inf lamina ble Extremely flammable/ Ext Tenement Inflammable drawn tightly across the open spaces. The test is conducted by equilibrating three identical dispensers to 71.6 ± 3.8°F (22 ± 2°C). They are shaken and given a 5 second discharge to clear the dip tube of possible propellent. After fixing the first can in the stand, the flame is lit and a trial flame projection is made to see if the second flame position and height are to be required for combustion. Assuming a flame projection is achieved with at least one of the flame settings, the nearest open frame is fitted with cheesecloth and the aerosol is then sprayed at it, through the flame, for 5 seconds. If the cloth burns the test is repeated using the second frame. Any flashback to the container is noted, as well as any lack of flame projection. The remaining two units are then tested. The longest flame projection that causes burning of the cheesecloth is the one considered for labeling purposes. The labeling consequences of the flame projection test are shown in Table IV. The text is bilingual (English and French) since this is a general labeling requirement for all Canadian products. The industry is not particulary pleased with the labeling regulation, which went into effect in 1982. They accepted the test and definitions because the Federal Department for Consumer and Corporate Affairs was considering the use of a combination of the Flame Projection Test, Closed Drum Test, Modified Tagliabue Open Cup Flash Point Test and 45% Flammables Assessment as an alternate approach. The concept of calling an aerosol "Flammable" (triangle symbol) if there is any flame elongation whatever seems unduly harsh. With the continuing decline of CFCs in Canada, the test will have the effect of pronouncing as "Flammable" virtually all products that do not contain very large quantities of water, methylene chloride or 1,1,1 -trichloroethane. Tests using large numbers of cans have shown about a ± 6% variation in actual flame length for the same can, about ± 12% for different cans of the same product, and ± 20% for different cans (with vapor-tap valves) of the same product. These findings are matched by results obtained in BAMA (England) and CSMA testing programs. Considering this, there is an industry feeling in Canada that about 10% should be added to the average flame length of the three test cans. Thus, an average result of 16 " (406 mm) would probably be adjusted to a maximum result of 17.6" (447 mm), which would cause burning of the cheesecloth positioned at the 17.7 " (450 mm) distance. The product would then be considered "Extremely Flammable".
Aerosol Flammability 211 Aerosol Flammability Regulations in Argentina Argentina and several other Latin American countries have adopted the CSMA Flame Projection Test method as their criterion for the determination of aerosol flammability. Under Resolution No. 710 of Law No. 19,982, the Secretary of State, Commerce and International Economic Negotiations published IRAM Regulation No. 3793 (Oct. 3, 1978) to establish flammability labeling of aerosol products in Argentina. The testing device is essentially identical to that in use in the U.S.A., described in detail later in this chapter. The regulation covers all aerosols of capacity greater than 100 ml, except that for unprotected glass containers the pressure may not exceed 14.3 psig (1.00 kg/cm2 or 98.6 kPa). According to the results of the Flame Projection Test, aerosols are classified as follows: a. Class A. If the flame extension is greater than 17.7" (450 mm) or shows a flashback to the dispenser, the label must state, "Inflammable, do not spray over flame." b. Class B. If the flame extension is from 7.9 " to 17.7 " (200 to 450 mm), the label must Figure 5. U.S.A. Flame Projection Testing Device Components: Heavy-duty poly-ethylene support base, about 8"x36"x2" (200x915x51 mm) Three '%,* (12 mm) aluminum support rods for rule, preferably covered with Vz" (12,7 mm) i.d. Teflon tubing to prevent corrosion Clear epoxy-coated heavy aluminum stick-ruler, marked to 24" in 1" increments Metal centering ring for candle or gas burner Adjustable-arm candle clamp, mounted on 6" (150 mm) support rod Container support base and positioner, adjustable in height state, "Combustible, do not spray over flame." c. Class C. If the flame extension is 7.9" (200 mm), the label must state, "Do not spray over flame." Odier labeling, required for both flammable and non-flammable aerosols, includes the phrases: "Do not expose to temperatures greater than 50°C. Do not throw into fire or incinerator. Do not puncture. Refilling is prohibited." Labels must also indicate the brand and name of the merchandiser. Products are to be marked with the net contents in terms of grams and/or volume in cubic centimeters. In the special case of cosmetic products, they may be pressurized with either carbon dioxide or CFC propellents, or CFCs mixed with hydrocarbons provided the flame projection is not over 7.9 " (200 mm). They are not permitted to use hydrocarbon propellents, exclusively. Because of economics, there has been a strong tendency to use propellents that are rich in butane (or even exclusively butane), and the Ministry of Public Health has had to monitor filling plants very closely to enforce this difficult law. U.S.A. Flame Projection Test The test apparatus in use today is still the same as that approved originally by the CSMA in 1951 and inserted into the Interstate Commerce Commission tariff in 1952. A rather elegant model, developed by the author, is shown in Figure 5, as well as the CSMA Aerosol Guide (Seventh Edition; April 1981) and other publications. Tester designs vary widely. Every laboratory will normally build their own equipment. Since the hot flame plume curves upward, the horizontal ruler should be placed at least 6" (150 mm) above the dispenser actuator. (See Page 485 for exact method.) Testing should be done in a draft free area that can be ventilated and cleared of fumes after.each test. Large amounts of product should not be sprayed in. small, confined areas. If the formulation contains chlorinated hydrocarbons or CFCs, any burning of the spray will act to form toxic materials, such as formic acid, hydrochloric acid, hydrofluoric acid and traces of phosgene. Operators should then vacate the testing area immediately after completing each test, allowing it to be ventilated. Nasal irritation, along with possible headache, nausea and diarrhea, may result from excessive exposure.
212 The Aerosol Handbook The flame projection test is conducted as follows: a. Equilibrate the dispenser to 70 ±1°F (21 +0.5°C) in a water bath. b. Shake the dispenser and spray briefly to clear any layered phases from the dip tube. Hold upright in the tester unless the labeled directions anticipate inverted use. c. The dispenser is actuated by hand (or with a rod) so that the spray passes through the top third of the flame, located 6 " (150 mm) away. The button is fully depressed for 4 seconds, during which a second operator notes any extension of the flame and any flashback. d. The test is repeated twice more with the same dispenser. e. The flame projection and/or flashback figures are averaged for reporting purposes. This procedure is equivalent to the one in the CSMA Aerosol Guide and ASTM Standards. It represents the best thinking of the aerosol industry. It is extremely unfortunate that the Federal Hazardous Substances Act regulations, developed by the FDA in 1960, contain an elaboration of this procedure to add the concept of ' 'flashback (a flame extending back to the dispenser) at any degree of valve opening''. The regulations were transferred to the CPSC in 1973 and the flashback definition was copied by the EPA about 1975 in the interest of regulatory harmony. To fully comply with the current regulations for CPSC and EPA products, the industry procedure must be extended by either spraying the product into the top third of the flame while slowly releasing the button to choke off the spray, or by aiming the product at the top third of the flame while slowly depressing the button to cause a gradual increase in spray rate. This aspect of the test has no pragmatic significance whatever. It was added by two FDA technicians who knew very little about aerosols, and who wanted to prevent persons having the end of their index finger burned if the spray accidentally caught fire. In reality, it is extremely hard to operate an aerosol valve in anything other than a wide-open position. If the spray did indeed catch fire, only in the rarest of instances would the flashback reach fully back to and touch the button at full actuation. One low-pressure cologne was shown to do this in some instances. The development of a flashback is a relatively slow process; it takes a second or two for the flame to fight its way back against the forward velocity of the spray. This would give the user plenty of time to release the actuator, causing a complete and immediate extinction of the spray and flame. The gross effects of throttling off the spray are to increase particle size, lower the delivery rate and (most importantly) reduce the forward velocity of the spray. Depending upon the valve system, most aerosol sprays emerge from the actuator at forward speeds ranging from 10 to 32 ft/sec (3.05 to 9.75 m/sec). After the first 1" (25 mm) of travel, the velocity is reduced by about 25%, due to break-up and air friction. The break-up introduces a widening range of velocities, since the explosion of a large initial particle into a host of smaller ones has vectors in all directions, including both forward and backward motions. The burning velocity of propane gas in air is 10.6 ft/sec (3.23 m/sec) and that of the butanes is about 9.3 ft/sec (2.83 m/sec) at ambient temperatures. The degree to which flashback extends toward the dispenser depends upon where the forward average velocity of the spray equals the backward burning (flame front) velocity of the flammable gases. (Note: only gases burn; not liquids or solids, which ignite only to the extent that they can form vapors.) At full actuation of a very flammable product the flashback will extend from 3.0 to 4.5 " (76 to 114 mm) toward the dispenser — almost always missing the actuator by at least 1.5 "(38 mm). When the aerosol spray is deliberately throttled, the situation becomes quite different. The forward motion of the spray is reduced dramatically, and this quite often allows the flame to return to (and touch) the actuator if the spray is ignited. Again though, the return is slow enough that the user has ample time to release the button or even drop the aerosol, thus positively shutting off both spray and flame within a split second. Should the operator deliberately keep operating the dispenser in this unique, partly throttled fashion, then the flame may reach the sprayhead. For many products, particularly ethanol types, the button will have become wetted with product around the terminal orifice, so that when the flashback flame touches it the concentrate will ignite to produce a small candle-like flame perhaps 1.3 " (33 mm) high. This secondary flame will only last a second or two, but it will cause a heat blister on the finger of the operator. The profoundly critical effect of the "flashback...at any degree of valve opening" has been illustrated by specific tests with 23 non-CFC and 3 CFC type aerosols representing commercial type formulations (see Table V).
Aerosol Flammability 213 Table V Aerosol Flammability Test Results at Full Percentages of Full Delivery Rate Product Type General Formula Valve Description Flame Projection/Flashback 100% D.R. 50% D.R. 25% D.R. Test Result* Personal Deodorant Personal Deodorant Disinfectant/ Deodorant Hair Spray Hair Spray Hair Spray Hair Spray Hair Spray (Fluorocarbon) Hair Spray (Fluorocarbon) Hair Spray (Fluorocarbon) Actives Alcohol n-Butane co2 Actives Alcohol Prop. A70 Actives Alcohol DX Water Prop. A46 Actives Alcohol OH2CI2 Prop. A70 Actives Alcohol GH2CI2 Prop. A31 Actives Alcohol Prop. A46 Actives Alcohol CH2CI2 Prop. A46 Actives Alcohol CH2CI2 P-ll/12 Prop. A31 Actives Alcohol CH2CI2 P-ll/12 Prop. A31 Actives Alcohol Prop. A 0.93% 76.07% 18.00% 5.00% 1.77% 61.23% 37.00% 0.88% 53.09% 26.03% 20.00% 1.94% 66.07% 12.00% 20.00% 2.50% 55.00% 12.50% 30.00% 3.30% 60.70% 36.00% 3.30% 59.70% 12.00% 25.00% 2.00% 58.00% 8.00% 32.00% 1.60% 34.00% 9.00% 50.00% 5.40% 1.16% 43.84% 55.00% Precision 0.013 "stem 0.060 "body 0.017" capillary 0.016" Delta Concave Summit S-63 0.030 "stem 0.088" body 0.016" Vapor-tap 0.009 70.011 "MB Summit S-63 0.016" stem 0.022" body 0.016" MB button Precision 0.013 "stem 0.061 "body 0.017" capillary 0.016" RT button Summit S-63 0.016" stem 0.016 "body 0.020 "MB button Precision 0.016 "stem 0.025" body 0.013" Vapor-tap 0.013 "RT button Precision 0.013 "stem 0.080 "body 0.013" RT button Precision 0.018" stem 0.013 "body 0.018" Reverse taper Precision 0.018" stem 0.013 "body 0.018" Reverse taper Seaquist NS-31 0.016" stem 0.013 "body 16 74" 1075" 576" Extremely Flammable 10 70" 8 70" 6 70" Not Flammable 13 70' 12 "4" 672" 10 76" 15 73' 15 70' 12 76" 12 70" 0.020 " Reverse taper 274" 670" 8 70" 470" Extremely Flammable* * Extremely Flammable Extremely Flammable Not Flammable 20 75" 16 75" 1270" Flammable 17 74" 1470" 970" Not Flammable 16 72" 1470" 870" Not Flammable 19 70 " 18 70 " 10 '70 " Not Flammable •As per the Federal H.S.A., used by the E.P.A. and C.P.S.C. (Not FDA.) **6" flashback achieved at less than 1/4 delivery rates.
214 The Aerosol Handbook Table V - Continued Product Type General Formula Valve Description Flame Projection/Flashback 100% D.R. 50% D.R. 25% D.R. Test Result* Leaf Polish Actives IPA CH2CI2 iso-Pentane co2 2.30% 27.70% 30.00% 37.00% 3.00% Seaquist NS-31 0.010" stem 0.011 "body 0.015 "button 20 70" 1170" 3 76" Extremely Flammable S.S. Cleaner Shoe Shine Insecticide Roach & Ant Sp. Surfactant 2.50% Seaquist NS-31 Solvent 2.00 % 0.016" stem Distillates 26.00% 0.018 "body Perf./Pres. 1.30% 0.016" Dynamist but. DX Water 51.20% Prop. A60 15.00% Actives 10.2% Seaquist NS-31 IPA 20.0% 0.011 "stem CH3CC13 46.8% 0.010" body Prop. A108 23.0% 0.015" Reverse taper Actives 0.9% Precision Pet. Dist. 79.1% 0.018" stem Prop. A55 20.0% 0.018" body 0.018" Reverse taper Actives 1.0% Seaquist NS-31 Solvent 7.5% 0.013" stem Pet. Dist. 88.9% 0.013 "body C02 2.6% 0.018" actuator 12 72" 1270" 6 70 " Not Flammable 1170" 670" 370" Not Flammable 20 73" 13 70" 676" Extremely Flammable 2470" 20 76" 12 76" Extremely Flammable Hair Spray Actives 1.6% Precision Alcohol 58.4% 2x0.020" stem Prop. A46 40.0% 0.080" body 0.020" vapor-tap 0.020 " actuator 2470" 1470" 770" Flammable Hair Spray Developer Actives 4.2% Ethyl Corp. PARC-39 2470" 1270" 676" Alcohol 53.8% 0.016" stem CH2CI2 15.0% 0.018 "body Prop. A46 27.0% 0.020" MBU RKN-62 Actives 2.5% Ethyl Corp. AR-74 17 70" 1270" 1070" Pet. Dist. 37.5% 0.016" Vapor-tap Prop. A46 60.0% 0.040" Capillary 0.018" RAR-90 button Extremely Flammable Not Flammable Suntan Oil Concentratet 53.0% Prop. A31 47.0% Seaquist NS-31 0.018 "stem 0.018" body 0.013" Vapor-tap 0.018" actuator 20 70" 15 70" 376" Extremely Flammable Hair Dressing Actives 7.00% Summit S-63 IPM 6.60% 0.016 "stem Alcohol 52.35% 0.016 "body Prop. A70 34.00% 0.016" Vapor-tap 0.013"MB button 8 70" 6 70" 0 70" Not Flammable TLargely mineral oil, plus cocoa butter, lanolin, screening agent, scent, etc.
Aerosol Flammability 215 Table V - Continued Product Type General Formula Valve Description Flame Projection/Flashback 100% D.R. 50% D.R. 25% D.R. Test Result* Silicone Lubricant Antistatic Spray Burn Spray Butter Spray Athlete's Foot Suntan Oil Spray Actives 3.75% Pet. Dist. 30.00% CHs-CCU 62.45% C02 3.80% Actives 1.70% Mineral Sp. 35.00% CH2C12 58.30% C02 5.00% Concent.* 75.00% CHs-CCb 5.00% Prop. A31 20.00% Actives 3.00% Soy Bean Oil 94.00% C02 3.00% Actives 3.00% Ucon Fluid 5.00% Alcohol 20.00% Prop. A31 72.00% Actives 1.00% Mineral Oil 12.12% Veg. Oils 50.00% Prop. A40 36.88% Seaquist NS-31 0.011 "stem 0.010 "body 0.016"Excel Dy.M. Precision 0.013 "stem 0.062" body 0.020 "capillary 0.018" MB Concave Precision 0.020" stem 0.080 "body 0.016 "MB-ST button Newman-Green R-70-118 160-20-73 Sprayhead Ethyl Corp. T-56 0.016 "stem 0.016 "body 0.016" Vapor-tap RK-23 button Seaquist NS-31 0.018" stem 0.018 "body 0.018" button 1470" 0 70" 16 "3" 1170" 2470" 6 72' 22 70" 12 70" 070" 13 70" 1270" 8 70' 2 70' 6 70" 0 70' 8 76' 1474" 6 76' Not Flammable Flammable Flammable Not Flammable Extremely Flammable Extremely Flammable *Mainly vegetable oil; plus 4% benzyl alcohol, 2% benzocaine, oxyquinoline and other items. Hydrocarbon-propelled products found to be extremely flammable included hair sprays without vapor-tap valves, personal deodorants without vapor- tap valves, athlete's foot spray, disinfectant/deodorant spray, sun tan spray and a leaf polishing spray. Hydrocarbon based antiperspirants (typically containing 72% isobutane) and colognes have not been included in Table V, but are recognized from other studies to be generally in the extremely flammable category, depending upon formula and (more importantly) valve selection. It is important to reiterate that two tests must be failed if an aerosol formula is to be considered extremely flammable: the flashback portion of the Flame Projection Test, and the Modified Tagliabue Open Cup (TOC) test. For EPA products the concentrate must have a TOC flash point of 20°F (-6.7°C) or less; for CPSC products the entire aerosol formulation must have a TOC flashpoint of 20°F (-6.7°C) or less. FDA type products are not covered. The Flame Projection Test is applicable to about 86% of all U.S.A. aerosol products. The principal exception is foam products, particularly shave creams and whipped creams, but other formulations such as pastes, lotions, pour-products, meter-sprays and so forth may also be impossible to test because they do not produce a sustained spray upon actuation. Products with a variable flow rate, such as the Newman-Green V-8 Series with Model 166 Series sprayhead, should be tested at the high/low or high/medium/low delivery rate choices, and the product should be labeled according to the most critical results encountered. Where extension tubes are used, the end of the tube should be positioned horizontally, 6" (152 mm) from the ignition flame. Tube lengths range from about 1" to 6 " (25 to 152 mm) in the case of silicones, cleaning fluids and penetrating oil lubricants, on up to 30" (762 mm) in the case of a 99.2% methyl Cellosolve nitrosol pack used as a fuel additive for jet airplanes. If the product can be used with or without the extension tube, according to direc-
216 The Aerosol Handbook tions for use, then both dispensing modes should be tested. The Flame Projection Test was designed as a consumer-oriented assay, bearing only a general relationship to storage and shipping considerations. It merely determines the ability of the spray to burn, without relevance to flashpoint, delivery rate, BTU content or other parameters. This can be easily illustrated. Methylene chloride has no flash point under ordinary atmospheric conditions, simply because it boils first — at 103.6°F (39.8°C). But when tested at supra-atmospheric pressures, such as those found in a mine, it displays a TOC flash point of 121°F (49.4°C). Despite the fact that it has a flashpoint under such conditions, it cannot be made to burn in the Flame Projection Test. In one experiment pure methylene chloride was heated in an aerosol can to 160°F (71.1°C), where it gave a pressure of 29 psig (200 kPa). Upon spraying, the dispenser produced an excellent spray pattern, but with no trace of flammability. Propane was then added to methylene chloride in increasing amounts, checking for possible flame projection with the dispenser equilibrated to 70°F (21.1°C). At 70% propane occasional very short bursts of blue flame were produced. Longer flame projections were obtained as still higher levels of propane were tested. The data are illustrated in Figure 6. Figure 6. Flame Projection Diagram Chart illustrating flame projection of methylene chloride/propane mixtures. Temperature = 70°F (21 °C). PVC valve, with 0.013" stem, 0.018" body, standard dip tube, Viton seat and cup gaskets and 0.016" MB-ST actuator. 20 18 16 14 12 10 2 - III It flTrrrr- Tt:fi_-_ 508 457 406 356 _ 305 5 s 254 2 H O W ft 203 152 102 51 10 20 30 40 50 60 70 PER CENT PROPANE 80 90 100 The situation with isobutane and Halon 1301 (CF3Br) is even more spectacular. As little as 5v% of Halon 1301 in air effectively prevents the hydrocarbon from burning, due to a unique free-radical reaction mechanism. Methylene chloride has a heat of combustion amounting to 2,262 BTU/lb (126 kcal/100 g). The heat of combustion of a 67% propane and 33% methylene chloride solution is calculated as 15,231 BTU/lb (852 kcal/100 g). This is higher than ethanol, isopropanol and acetone, and on a par with diethyl ether. The fact that the mixture fails to burn in the Flame Projection Test shows that the test can be very insensitive to the BTU or caloric value of aerosol formulas. Similarly, the test results are unaffected by the flash point of the aerosol composition. The non-flammable mixture of 67% propane and 33% methylene chloride has a flash point estimated at -142°F (-97°C), which is lower than at least 95% of all U.S.A. aerosol formulations. Conversely, the 100 psig (689.5 kPa) mixture of about 99.6% high-boiling USP mineral oil and nitrogen has a TOC flash point of typically 565°F (296°C) and can be made to cast a flame upwards of 20 feet (6.1 m) with the right valve. With standard taper valve buttons, however, flame projection may be zero. The similar mixture of USP mineral oil and 2.1% carbon dioxide will cast a very long flame with virtually any valve selection, merely due to the greater degree of break-up. As mentioned earlier, valve design has a profound effect upon flame projection and flashback results. Reducing the delivery rate, by using a smaller inner orifice (stem orifice), will decrease flame projection considerably, but will have little effect upon flashback. Reducing the delivery rate by using a smaller tailpiece orifice will cause gas formation within the mixing chamber of the valve and cause both flame projection and flashback to dwindle accordingly. The use of a vapor-tap orifice has the dual effect of reducing delivery rate and bringing gas directly into the mixing chamber; thus this approach is effective in reducing both flame projection and flashback — often to zero, if the vapor- tap orifice is sufficiently large. The effect of reducing delivery rate by adjusting the inner orifice size, and by increasing the size of the vapor-tape from zero to 0.020 " (0.51 mm) is shown in Table VI. These results were obtained by using the same valve for each horizontal test series. A simple split toroid clamp (developed in Europe) is ideal for fixing the valve
Aerosol Flammability 217 tightly down on the can bead without the necessity of crimping. At the end of a particular test the dispenser is emptied and the clamp loosened. Both valve and clamp are transferred to a new can containing the desired concentrate mixture. After tightening the clamp, T-t-V gassing is used to pressurize the dispenser with the correct amount of propellent. (See Figure 1, Page 283.) By the use of the same valve, the inevitable delivery rate differences between valves can be avoided. These variations can often get to ± 15% and cause considerable pertubations in the results unless determinations on several individual cans are averaged. Large variations in product density, viscosity and pressure will affect delivery rate uniformity from a given specific valve. In some cases the effect of methylene chloride or other strong solvents will act to reduce delivery rate. The data in Table VI show that vapor-tap valves can reduce flame projection of ethanol/hydrocarbon formulas down to less than 6 " (150 mm) and eliminate flashback entirely. In associated tests with a 0.023 " vapor- tap valve, both flame projection and flashback were eliminated. An extreme example is given in the literature, where 100% propane (as gas, at 70°F - or 21.1°C) exhibited a delivery rate of 1.08 g/s and failed to ignite in the flame projection tester. In the same sequence, 100% isobutane delivered at 0.34 g/s and also failed to ignite. The spravs could be used to extinguish the candle flame, as could that of P- 152a gas. Table VI Flammability of Selected Hair Sprays by the Flame Projection Test Formulas and Test Results Ethanol (100%) Methylene Chloride Propellent A-46 75% — 25% 27.5 700 6.0 150 23.0 585 6.0 150 17.0 432 6.0 150 60% 15% 25% 23.5 597 6.0 150 22.0 559 6.0 150 15.5 394 6.0 150 45% 30% 25% 21.5 546 6.0 150 20.0 508 6.0 150 14.0 356 6.0 150 40% 35% 25% 20.5 521 6.0 150 17.0 432 5.0 127 12.5 318 6.0 150 30% 45% 25% 19.0 483 3.0 75 15.0 381 4.0 102 10.0 254 5.0 127 15% 60% 25% — — — 7.0 178 0.0 0 — — — 60% — 40% — — — 22.5 572 6.0 150 — — — 25% 35% 40% — — — 20.0 508 6.0 150 — — — At D.R. = 0.70 g/s Flame Projection (") (mm) Flashback* (") (mm) At D.R. = 0.45 g/s Flame Projection (") (mm) Flashback* (") (mm) At D.R. = 0.20 g/s Flame Projection (") (mm) Flashback* (") (mm). At D.R. =0.45 g/s 0.013 "Vapor-tap Flame Projection (") (mm) Flashback* (") (mm) 0.016" Vapor-tap Flame Projection (") (mm) Flashback* (") (mm) 0.020" Vapor-tap Flame Projection (") (mm) Flashback* (") (mm) 20.5 521 6.0 150 18.5 470 6.0 150 5.5 140 0.0 0 16.0 406 6.0 150 5.5 140 0.0 0 2.5 64 0.0 0 *With valve in a fully opened position.
218 The Aerosol Handbook Particle size is another important parameter in the flame projection test. Fortunately, in the U.S.A. the test procedure anticipates the use of full cans. In other countries this is not always the case. For example, in the Swiss Official Methods aerosol dispensers having contents in excess of 50 g must be tested when full, 50% empty and 90% empty. Where the content is less than 50 g the test is conducted only at the 50% full level. As a rule, the flame projection test results are made more critical by partially emptying the dispenser, since the spray normally becomes coarser and carries the flame further. The difference is particularly noticeable in the case of vapor-tap gradually becomes less effective due to the partial loss of propellent. Many vapor-tap systems use formulations that are typically 5% concentrate, 65% water and 30% hydrocarbon propellent. Table VII Flame Projection Test Results for an Insecticide Formula: 67.5 to 77.5% (10 parts Isopropanol and Toxicants, plus 90 parts 1,1,1-Trichloroethane) 22.5 to 32.5% Hydrocarbon. Valve: Summit Model SV-78, with stem, body and actuators as noted. Temperature - 70°F (21°C). Propellent Blend A-46 NP-52 NP-52 NP-52 NP-65 NP-65 NP-65 NP-65 NP-65 NP-65 NP-65 NP-65 NP-65 NP-65 NP-65 NP-65 NP-65 NP-80 NP-80 NP-80 NP-80 NP-80 NP-80 NP-80 NP-80 NP-80 A-108 A-108 A-108* A-108 A-108 A-108 A-108 A-108 A-108" A-108 % 30.0 30.0 32.5 32.5 22.5 22.5 22.5 25.0 25.0 25.0 25.0 25.0 25.0 25.0 25.0 25.0 27.5 22.5 22.5 22.5 22.5 22.5 22.5 22.5 22.5 22.5 22.5 22.5 25.0 25.0 22.5 22.5 22.5 25.0 25.0 25.0 Valve Stem 0.020" 0.020" 0.020" 0.020" 0.020" 0.020" 0.020" 0.020" 0.020" 0.020" 0.024" 0.024" 0.024" 0.016" 0.016" 0.016" 0.020" 0.020" 0.020" 0.020" 0.020" 0.016" 0.016" 0.020" 0.020" 0.020" 0.016" 0.016" 0.016" 0.016" 0.020" 0.020" 0.020" 0.020" 0.020" 0.020" Valve Body 0.080" 0.080" 0.080" 0.080" 0.080" 0.080" 0.080" 0.080" 0.080" 0.080" 0.062" 0.062" 0.062" 0.062" 0.062" 0.062 " 0.080" 0.080" 0.080" 0.080" 0.080" 0.062 " 0.062" 0.080" 0.080" 0.080" 0.062" 0.062" 0.062" 0.062 " 0.080" 0.080" 0.080" 0.080" 0.080" 0.080" Valve Button AX-8359 AX-8359 AX-8359 0.040 "Ext. AX-8359 0.025" Ext. 0.023 " Str. AX-8359 AX-8359 AX-8359 AX-8359 0.025" Ext. 0.023 " Ext. AX-8359 0.025 " Ext. 0.023" Ext. AX-8359 AX-8359 0.025" Ext. 0.023" Ext. 0.023 " Ext. AX-8359 0.025 " Ext. 0.025 " Ext. 0.025 " Ext. 0.023" Ext. AX-8359 0.025 " Ext. AX-8359 0.025 " Ext. AX-8359 0.025 " Ext. 0.023" Ext. AX-8359 0.025" Ext. 0.023 "Ext. Pressure P"g 30.0 33.0 35.0 35.0 38.0 38.5 38.0 39.0 43.0 43.0 44.0 44.0 44.0 42.0 42.0 41.5 41.0 45.0 45.5 45.0 44.0 47.5 45.0 44.0 44.0 44.0 61.5 61.5 66.5 66.0 61.5 61.0 62.0 65.0 64.5 65.5 kPa 207 228 241 241 262 265 262 269 296 296 303 303 303 290 290 287 283 310 313 310 303 328 310 303 303 303 424 424 459 456 424 421 428 448 445 451 Del. Rate (g/») 2.60 2.46 2.50 2.67 2.52 2.43 2.47 2.66 2.89 2.74 2.80 2.75 2.58 1.75 1.79 1.68 2.65 3.01 2.90 3.11 3.14 3.36 1.82 — 2.78 2.59 2.60 2.00 2.48 2.00 3.40 2.68 2.58 3.48 2.70 2.60 >24 >24 >24 >24 32 32 24 0 0 >24 32 32 32 24 0 0 >24 26 27 0 24 22 0 24 0 0 0 0 0 0 0 0 0 0 0 0 Flam Proj. (in) >24 >24 >24 >24 30 32 32 0 >24 0 32 29 33 23 24 0 >24 29 25 24 22 26 0 24 0 24 0 0 0 0 0 0 0 0 0 0 >24 >24 >24 >24 35 34 26 >24 >24 >24 30 28 30 24 24 0 >24 24 28 0 24 24 0 0 0 24 0 0 0 24 0 0 0 0 0 0 *Best of group in terms of 0" flame projection and good economics. "Second best of group, same basis.
Aerosol Flammability 219 The initial fine mist of water serves to quench the potential flammability of the hydrocarbon — normally A-31, A-40 or A-46. But as propellent is progressively lost during operation of the dispenser, the water droplets become larger and less effective. At this point long bursts or gusts of blue flame will start to appear in the test, slowly changing to a steady flame as the unit is emptied still further. The phenomenon of sporadic long spates of flame is not uncommon. It occurs where large percentages of flame suppressant substances are present in the formulation, such as water, methylene chloride or 1,1,1-tri- chloroethane. Outside the U.S.A. it is sometimes encountered with CFC formulations. Outstanding examples of sporadic, long-reach flaming can be found with the hydrocarbon/1,1,1-trichloroethane system, where the hydrocarbon is a high pressure type, used at about 25% of the total composition. Examples are shown in Table VII. Flame projection is suppressed by lowering the delivery rate, but only to a slight degree. Reducing the concentration of the hydrocarbon propellent obviously is useful. But the best way to prevent occasional flaming is to decrease particle size by using (in this case) straight propane. Propane has significantly more break-up ability than the various blends of n-butane/propane shown in the table. In some of these tests there was no flaming for the full 4 second spray period, to be followed by a momentary 30" (762 mm) burst as the valve was released. In conducting the test, flame bending should not be recorded so as to indicate a slight degree of flammability. Dispensers containing two separate liquid phases should be shaken just before each test. Otherwise, hydrocarbon type formulas will give falsely optimistic results. The dip tube should always be cleared before testing, or momentary long-reach flames might result from trapped or phase-separated hydrocarbon propellents in the tube. It is very important to keep test cans at the 70°F (21°C) temperature. If a constant temperature bath is not available in the testing area, the cans should be kept in an insulated bucket of 70°F (21°C) water before or between uses. The delivery rate should be recorded, for those cans tested. If the delivery rate of other cans of the same product is significantly higher, due to valve variation, air entrapment or other causes, the test should be repeated using the highest delivery rate can available. Some marketers use a test variation allowance of 1 to 2 inches (25 to 50 mm), which is added to the flame projection result found during product development. Others feel that 90 to 95.5% of the cans should fall within a flame projection range equal or less than the flame projection "maximum" value, recorded in product specifications. Much criticism has been devoted to the shortcomings of the flame projection test. Despite the spectacular and simplistic nature, it has little pragmatic significance in terms of consumer hazard. Well over 90% of consumer fires are caused by product misuse, such as overheating the dispenser in or on a stove, in a backyard incinerator (sometimes called a ' 'burn barrel") or in a place heated excessively by the sun. In other cases, dropping the container may act to cause valve leakage (frequency below 1%) if the cover is not in place. If the dispenser is already severely overpressurized, due to heating, dropping may cause it to burst. Nearly all fires that are caused by actually spraying the aerosol are surface coating fires, where the application of the spray causes a hard or absorbant surface to become flammable. During pre-aerosol days, numerous fires were started by pump-sprayers (the old- fashioned "Flit gun") used to treat the tops of cast iron plate stoves with kerosone-based stove polishes or insecticides. The gas or coal fires often burning below the heavy ironplates might then cause the hot kerosone to flare up and severely burn the person doing the spraying. In a more modern setting, during the early 1970s a number of oven fires and "whoosh" types explosions were encountered in England after the introduction of aerosol oven cleaners, containing about 20% of a combustible organic solvent in addition to the 5% or so of isobutane propellent. After the foam layer broke and much of the water evaporated, the solvent vapors exceded the lower explosive limit (LEL) concentration in air, and when this mixture came into contact with the oven pilot light very rapid burning resulted. The British Aerosol Manufacturers Association (BAMA) reacted quickly. Their Code of Practice (Fourth Edition - 1980) now states that "Flammability hazard under in-use conditions shall be minimized by restricting the percentage of flammable contents to 6%w/w." The label also warns that the oven door should be kept open after spraying. Similar problems existed about 1972 in the U.S.A. and were recited by a consumerist group during the first formal hearing held by the newly created CPSC during that year, which happened to be on the subject of aerosol safety. The glow from burning cigarettes or cigars is not sufficiently hot to ignite a potentially flammable aerosol
220 The Aerosol Handbook spray — despite unsubstantiated reports that are received every five years or so, suggesting mat the momentary, tiny fire on certain charring cigarette papers can cause sprays to ignite. As a result, the applicability of the flame projection test results in the real world would seem to be limited to the spraying of oven gas stove or hot water heater pilot lights. In one case, an insecticide containing 50% hydrocarbon propellent was claimed to have ignited the area under a gas-fired refrigerator when the spray contacted the pilot light. No reports have been seen regarding combustion from gas- fired floor furnaces or electrical resistance wire heaters. The flame projection test remains as the most popular assay for aerosol flammability, despite its many shortcomings of bom a technical and pragmatic nature. It is certainly to be preferred over other individual flammability tests, and also offers the development chemist the flexibility of adjusting products to pass the test by various alterations of formultion and valve design. U.S.A. Closed Drum Test This test is of little importance today, so coverage is correspondingly brief. It was developed concurrendy with the Flame Projection Test in 1951 and made a part of the I.C.C. regulations during the following year. It is still in the latest interstate shipping tariff, but is applied only to those institutional or industrial products between 35 to 50 cu. in. (573.6 to 819.4 ml) for which mere is no consumer counterpart product. Such products are extremely uncommon. A few other countries use the test; for instance, it is called the "barrel test" in the Swiss Official Methods manual and is used to assess Figure 7. Closed Drum Test Apparatus 55 gallon or 200 liter size drum the flammability of aerosols larger than 50 g of contents weight. An illustration of the Closed Drum Tester is given in Figure 17. (See Page 486 for exact test memod.) A complete description of the tester is provided in the CSMA Aerosol Guide (Sevenm Edition, April 1981), but briefly, it consists of a 55 (U.S.) gallon or 200 liter steel drum, laid on its side, with two 6"x6" (150x150mm) windows and eimer one (CSMA) or diree (I.C.C, Switzerland, etc.) 1.00" (25.4mm) diameter ports in the solid end, as shown in the drawing. The single port used in the CSMA and ASTM procedures is located at the top of the solid end. The other end is hinged to the drum body, or better, a sheet of eimer 0.0022 " (0.05 mm) polyethylene or 0.0005" (0.013 mm) nylon film is stretched over the drum body and held in place wim a very large rubber band or circular tension spring. A 1" (25 mm) diameter candle set in the center of me bottom is lit — with a long taper, dirough a port, if the end is plastic covered. Immediately start spraying the 70°F (21°C) test can dirough the top port. Record spray time at full actuation until the LEL is reached and a large scale burning and pressure "whoosh" take place. In the U.S.A. procedure, the test may be terminated at 60 s if no result is obtained. In the Swiss method at least 20 g must be sprayed into the drum wimout effect, if the dispenser is to be considered non-flammable. The interpretive parameters for the smaller Japanese Closed Drum test have already been mentioned. Even mough the test has practically no regulatory significance any more, aerosol chemists still use it to assess the flammability of certain products, particularly those where large amounts of the formulation are released at any one time. Examples include the indoor fogger, where the can is latched open and sprayed to emptiness, undercoating products and so forth. Some laboratories prefer to measure flammable potential of mese products in terms of the number of cubic feet (or liters) that can be brought to a LEL by dispensing the entire can. In such cases, the cans will be sprayed until the drum flames and develops a pressure "whoosh", and the weight loss will then be determined. A simple calculation will then give the desired result. A candle flame is probably the best ignition source, but it has the disadvantage of removing some of the oxygen in the drum and also pre-burning a portion of the aerosol contents. In some cases, the candle flame will increase to a height of 18 " (457 mm) and touch the top surface of me drum, and still it may be a number of Next Page
220 Previous Page spray — despite unsubstantiated reports that are received every five years or so, suggesting mat the momentary, tiny fire on certain charring cigarette papers can cause sprays to ignite. As a result, the applicability of the flame projection test results in the real world would seem to be limited to the spraying of oven gas stove or hot water heater pilot lights. In one case, an insecticide containing 50% hydrocarbon propellent was claimed to have ignited the area under a gas-fired refrigerator when the spray contacted the pilot light. No reports have been seen regarding combustion from gas- fired floor furnaces or electrical resistance wire heaters. The flame projection test remains as the most popular assay for aerosol flammability, despite its many shortcomings of bom a technical and pragmatic nature. It is certainly to be preferred over other individual flammability tests, and also offers the development chemist the flexibility of adjusting products to pass the test by various alterations of formultion and valve design. U.S.A. Closed Drum Test This test is of little importance today, so coverage is correspondingly brief. It was developed concurrendy with the Flame Projection Test in 1951 and made a part of the I.C.C. regulations during the following year. It is still in the latest interstate shipping tariff, but is applied only to those institutional or industrial products between 35 to 50 cu. in. (573.6 to 819.4 ml) for which mere is no consumer counterpart product. Such products are extremely uncommon. A few other countries use the test; for instance, it is called the "barrel test" in the Swiss Official Methods manual and is used to assess Figure 7. Closed Drum Test Apparatus 55 gallon or 200 liter size drum The Aerosol Handbook the flammability of aerosols larger than 50 g of contents weight. An illustration of the Closed Drum Tester is given in Figure 17. (See Page 486 for exact test memod.) A complete description of the tester is provided in the CSMA Aerosol Guide (Sevenm Edition, April 1981), but briefly, it consists of a 55 (U.S.) gallon or 200 liter steel drum, laid on its side, with two 6"x6" (150x150mm) windows and eimer one (CSMA) or diree (I.C.C, Switzerland, etc.) 1.00" (25.4mm) diameter ports in the solid end, as shown in the drawing. The single port used in the CSMA and ASTM procedures is located at the top of the solid end. The other end is hinged to the drum body, or better, a sheet of eimer 0.0022 " (0.05 mm) polyethylene or 0.0005" (0.013 mm) nylon film is stretched over the drum body and held in place wim a very large rubber band or circular tension spring. A 1" (25 mm) diameter candle set in the center of me bottom is lit — with a long taper, dirough a port, if the end is plastic covered. Immediately start spraying the 70°F (21°C) test can dirough the top port. Record spray time at full actuation until the LEL is reached and a large scale burning and pressure "whoosh" take place. In the U.S.A. procedure, the test may be terminated at 60 s if no result is obtained. In the Swiss method at least 20 g must be sprayed into the drum wimout effect, if the dispenser is to be considered non-flammable. The interpretive parameters for the smaller Japanese Closed Drum test have already been mentioned. Even mough the test has practically no regulatory significance any more, aerosol chemists still use it to assess the flammability of certain products, particularly those where large amounts of the formulation are released at any one time. Examples include the indoor fogger, where the can is latched open and sprayed to emptiness, undercoating products and so forth. Some laboratories prefer to measure flammable potential of mese products in terms of the number of cubic feet (or liters) that can be brought to a LEL by dispensing the entire can. In such cases, the cans will be sprayed until the drum flames and develops a pressure "whoosh", and the weight loss will then be determined. A simple calculation will then give the desired result. A candle flame is probably the best ignition source, but it has the disadvantage of removing some of the oxygen in the drum and also pre-burning a portion of the aerosol contents. In some cases, the candle flame will increase to a height of 18 " (457 mm) and touch the top surface of me drum, and still it may be a number of
Aerosol Flammability 221 additional seconds before total burning takes place. These activities tend to prolong the spray time and give a result that is both optimistic and unreliable. If a large pre-ignition flame develops it is best to repeat the test. Other ignition sources have been tested. A micro- burner is equivalent to a candle flame. A spark plug works, but only if it has sufficient energy to ignite the LEL mixture. A fairly large (typically 20,000 v) neon light transformer is required. In one memorable test, conducted in Yonkers, NY during 1961 or so, and in front of the City of New York Fire Department, a flammable aerosol was sprayed into the drum until the LEL concentration was exceeded by a good margin. The spark plug was then activated, and an explosion ensued which resounded throughout the warehouse, tossed the drum several feet in the air, and released a huge gobbet of flame that extended clear to the 30' (9.1 m) ceiling structure. Similar experiments can be made on a much smaller scale using an aerosol can fitted with a spark plug and a loose cap or valve cup. Hot wires have also been tested. Nichrome (or chromel) wires are not hot enough. Like cigarettes and cigars, they have insufficent energy to reach the reaction threshold. A platinum wire, when electrically heated to an estimated 3000°F (1649°C), will cause ignition, but relatively thin wires will then melt quickly (3217°F or 1769°C) due to the combustion reaction on the white hot surface. In one test made with a 0.5 m diameter rhodium wire, which melts at 3560°F (1960°C), the wire survived. This general method of ignition cannot be recommended. The test is applicable to most continuous spray products, as is the flame projection test. Additionally, it will not work effectively on streaming sprays and a few other products types. It has been used with pump- action air sprays to show that, on a weight basis these products are just about as flammable as the hydro- carbon/ethanol aerosol hair sprays. This result would not have been predicted on the basis of LEL theory. Modified Tagliabue Open Cup Flash Point Test This test is based upon an archetype patented by Charles J. Tagliabue in 1862. The original version modified for aerosols, was first used by the I.C.C. in 1956 to distinguish levels of relative hazard in "flammable" aerosol products. It was later adopted by the FDA for use in the Federal Hazardous Substances Act (FHSA), about 1960, and then by the EPA as part of the testing routine to define both "Extremely Flammable" and "Flammable" aerosols. A complete text for the method appears in 38 CFR No. 187, page 27015 (Sept. 27, 1973), in the CSMA Aerosol Guide (Seventh Edition, April 1981) and other publications. Sketches of the tester and glass testing cup are shown in Figure 8. (See Page 485 for exact test method.) It is unfortunate that the official method is very cumbersome and lengthy, requiring triplicate standardization tests on two solvents, one initial test (to determine the approximate flash point) and then triplicate tests of the product under study. All this activity would probably take over a day, to get just one averaged result. It is almost never attempted, for that reason. As a rule, only one flash point test is run. There are a large number of devices for the determination of flash point, including the Pensy-Martens and Cleveland testers. Some are particularly useful within certain temperature ranges. The Tagliabue Open Cup (TOC) tester, for example, should not be used for liquids boiling at over about 175°F (80°C), and is much less reliable for liquids that are viscous, or tend to skin over. Testers are used in Europe and Japan that are relatively unknown in the U.S.A. During 1981, the Figure 8. Official CPSC Modified Tagliabue Open Cup Flash Point Tester
222 The Aerosol Handbook relatively new Setaflash Tester came into vogue in the U.S.A. For aerosol concentrates, it gives about the same results as the Tagliabue Closed Cup (TCC) device. In time, it may be used by the CPSC instead of the TOC or TCC, for some ranges. The open cup testers characteristically give somewhat higher results and are less sensitive to traces of volatile, flammable ingredients than the closed testers. The temperature difference can often be 10°F (5.5°C). the closed cup types are generally regarded as more sophisticated and more reliable. For instance, the CPSC is using the closed cup for pump-spray product evaluations. The ASTM Coordinating Committee on Flash Point (CCFP) developed a revised flash point definition in 1980 which reads, "the 'flash point' is the lowest temperature, corrected to a pressure of 760 mm Hg (101.3 kPa, 1013 bar) at which application of an ignition source causes the vapor of a specimen to ignite under specified conditions of test." In contrast, the term "fire point" can be defined as the lowest temperature, corrected to a pressure of 760 mm Hg (101.3 kPa, 1013 bar) at which application of an ignition source causes the vapor of a specimen to ignite and sustain such ignition, under specified conditons of test. The aerosol test container, flash cup and bath solution of the tester are all chilled to about -25°F (31.7°C). The aerosol unit is then punctured to release any propellent, such as CO2, which may still have some pressure at this temperature. The chilled formulation is then transferred to the flash cup, filling it to a level of exactly Vs" (3.2 mm) below the rim, after which the test is started. If the aerosol formulation freezes, becomes excessively viscous, forms crystals or becomes otherwise impossible to test as such, most industry experts feel the test should be aborted and flammability determined solely on the basis of the flame projection test. In the case of aerosol products that separate into two liquid layers, somehow the correct ratio of each layer should be transferred to the flash cup. This is rarely encountered, except for a few glycol type air fresheners and other relative oddities. The test interpretation is silent on the matter of how much material can volatilize off before the procedure is terminated. This was of considerable importance with the non-flammable CFC type propellents, suggesting for instance that a 80% CFC and 20% ethanol composition should be considered as less hazardous than one of 20% CFC and 80% ethanol. It is of no importance today, at least in the U.S.A. (Some of the TOC test procedures include terminating the test if the liquid level falls lA " (6.4 mm) in the brass flash cup.) The substitution of one flash point tester for another is never recommended. Flash point differences of up to 100°F (55.6°C) can be obtained when comparing closed cup methods, and differences of over 200°F (111.1 °C) can be measured when comparing open cup with closed cup methods. For aerosol flash points, the exact apparatus indicated in Figure 8. To a degree, flash points can be roughly predicted. For example, it would be a waste of laboratory time to run a TOC flashpoint on an isobutane/ethanol hair spray. The result is always far lower than the initial -25°F (-31.7°C) testing temperature. The addition of up to 10% water or 20% methylene chloride to these formulations does not act to change the flash point significantly. The CFCs can be used to quench the flash points of hydrocarbon propellents. Up to about 11.6% of isobutane can be rendered non flammable by the addition of 88.4% of P-12/11 (50:50). During the 1950s Dr. Winston Reed developed Propellent A, containing 10% isobutane with 90% P-12/11 (50:50) and patented it as non flammable under all reasonable conditions of testing and consumer use. Similar blends, such as Propellent P (for paints) were later used to some extent as nonflammable blends of CFCs and various hydrocarbons, dimethyl ether or vinyl chloride. Propellent 152a (CH3CHF2) has a flash point of below -58°F (-50°C), but despite this, it is so weakly flammable that it is rather easily formulated into non flammable blends by the addition of (ideally) a mixture of about P-12/11 (90:10) which has about the same vapor pressure. The flash point of an aerosol mixture bears little relation to flammable hazard. Aerosol formulations with flash points of -150° to 250°F (-101 to 121°C) can be easily made to produce virtually identical large or small flame projections. At one time a low-cost window cleaner aerosol was formulated with about 2% n-butane and 98% of a concentrate consisting almost entirely of water. It could not be tested for TOC flash point because the water froze during the chilling phase, but if this were not the case, the flash point would have been -101°F (-73.9°C), the same as an aerosol lighter fluid containing 100% n-butane. The two products can hardly be compared in terms of flammable hazard.
Aerosol Flammability 223 Table VIII provides TOC and TCC flash points for 36 common aerosol ingredients and a few mixtures. Additional values may be gleaned from manufacturers's Material Safety Data Sheets (MSDS) of the OSHA-20 format, as well as other literature. Because of the high predictability of a "flammable" vs. "nonflammable" result from this test, even large aerosol laboratories may run it only once every year or two, and then in an abbreviated format. Surface Flammability Tests It was not until about 1975 that a large group of industry experts sat down and compared the causes of consumer accidents involving flammability, with the finding that most of them related to the flammability of a sprayed surface. Data from press clippings, lawsuits, CPSC National Electronic Injury Surveillance System (NEISS) results and other inputs were all surveyed. Accidents resulting from ignition of an aerosol spray were considered to be less than 10% of the total. They occurred only when the spray impinged upon a flame, such as that of a match, gas stove or pilot light. Some resulted from overheating and bursting of aerosols, and these might be considered as some combination of vapor and surface deposits. But the preponderance involved the ignition of vapors arising from a sprayed surface, either during the time of spraying or shortly afterward. In some cases, people have been severely burned from both aerosol sprays and pump-action alcohol sprays as a consequence of gross negligence and misuse. In one instance, a young short order cook attempted to cool himself off by liberally spraying the front of his tee- shirt, using portions of an ethanol/CFC personal deodorant from two cans he found in his boss's shopping bag. He then returned to his gas-fired hot plate, whereupon the ethanol saturated tee-shirt caught fire. In a second case, three young women jumped hurriedly into the back seat of a car which was to take them to a Halloween masquerade party across town. They wanted to stiffen the taffeta on their costumes, so one of them had brought a large can of hair spray for that purpose. After they had applied most of the can to their apparel, one of them lit a cigarette. In a final example, we can recite a typical "hair aflame" situation, where a woman with a rather fluffy page-boy hair style applied many times the ususal amount of hair spray because of the windy conditions outside, and then lit a cigarette. Either a tiny flare from the match ignition caught the alcohol drenched hair on fire, or possibly a spray strand of hair acted as the link. These brief recitations indicate the potential danger of creating highly flammable surfaces. Methods for testing surface flammability have been developed in various countries. In the U.S.A. the preferred procedure was to spray the product for three seconds onto a Formica disc, 8 " (203 mm) in diameter, attempting to uniformly coat the surface. After five seconds, a lit taper or long-handled match is manually moved sideways toward the disc, starting at a point 8 " Table VIII Flash Points of Common Aerosol Ingredients and Mixtures Substance Propane P-12/Propane(91:9) isoButane n-Butane n-Pentane n-Hexane n-Heptane n-Octane (Gasoline area) n-Nonane n-Decane Gasoline Mineral Spirits Odorless Mineral Spirits Mineral Seal Oil - Typical Cocoanut Oil Corn Oil Methanol Ethanol Ethanol/Water (90:10) isoPropanol Ethylene Glycol Propylene Glycol Glycerin Acetone Methyl Ethyl Ketone (MEK) Methyl isoButyl Ketone (MIBK) n-Butyl Acetate isoUndecane (As Isopar H - Exxon) isoUndecane/Nonionic Emulsifiers (80:20) = UNE UNE/Water (50:50 Emulsion) UNE/Water (40:60 Emulsion) UNE/Water (20:80 Emulsion) UNE/Water (10:90 Emulsion) UNE/Water ( 5:95 Emulsion) Toluene Xylenes Flash Point (°F) Tagliabue Open Cup -156 -70 -117 -101 -45 -1 — — — — 102 128 255 510 590 60 62 — 60 240 225 350 15 — 62 90 — — — — — — — 45 75 Tagliabue Closed Cup -163 — -126 — <-44 -6 31 56 88 115 -50* 97 119 170 420 490 54 55 157 53 232 210 320 0 30 75 72 133 126 120 119 124 130 134 40 63 *Due to very small butane content.
224 The Aerosol Handbook Figure 9. Flammability of Surface Residues Tester Legend: A Duraluminum (duralumin or aluminum) sheet, 610 x 405 x 3 mm B Leg, 130 mm high (Six required) C Circle of metal, 200 mm diameter, preferably cut out and flanged below for support D Slot, about 260 mm long and 4 mm wide, cut along middle axis E Micro-burner F Worm-drive G yt HP or comparable electric motor H Reduction gear and pulley drive J Forward operating switch for motor J, Reverse operating switch for motor K Switch gear L Microswitches (two) overriding the operating switches, to prevent damage M Bearings to support worm-drive at each end N Bearings supports of 25 mm angle iron P Spacers to secu re micro-bu rner nozzle at same plane as su rface of sheet R Flange for supporting circle, if made removable as recommended X Upward view from arrow X, showing internals of instrument Y Detail view, showing method of affixing micro-jet burner to worm- gear (203 mm) distant and closing at about 1" (25 mm) per second. The distance to the disc was determined in the event a flash or sustained flame occurred. If the flame could be moved inward to touch the edge of the disc without causing an ignition of the sprayed product, then the result was considered non-flammable. The method was approved by the CSMA Aerosol Division Flammability Committee, but no agreement could be reached on how to classify the results, should ignition of the disc occur. Some members felt that this was the business of regulators, not scientists. Others felt the regulators might take the method, perhaps establish an interpretation of the results that would be overly restrictive, and add it to their current battery of test methods. In the end nothing was done, and the U.S.A. has no test for this very important aspect of flammability. In England, the British Aerosol Manufacturers Association (BAMA) developed their own version of this method during the late 1970s. They felt the need to utilize a relatively elaborate mechanized testing device (estimated cost $1500 in 1982), which is shown in Figure 9. The apparatus consists of a duraluminum (or duralumin) sheet, 28" long by 16" wide and %" thick (710 x 405 x 3 mm) mounted horizontally upon six legs 5 % " (130 mm) high. A circle 8 " (200 mm) in diameter is marked with its center 6" (150 mm) from the midpoint of one end. It is useful to actually cut the circle from the sheet, making it removable for cleaning purposes, and supporting it with a flange or similar arrangement. A slot about 10 54 " (260 mm) long and 0.16 " (4 mm) wide is cut along the middle axis of the sheet and is marked in inches or 10 mm divisions, beginning at the periphery of the circle. A micro-burner is positioned within the slot. By means of a motor and reduction gear drive the burner is caused to move within the slot at 1" (25 mm) per minute. The V8 H.P. motor is operated by both forward and reverse switches. The nozzle of the burner is maintained even with the surface of the sheet. Preferably three cans of the test product are equilibrated to 77°F (25°C). The first can is sprayed evenly upon the disc for three seconds and from a distance of about 10 " (250 mm). After five seconds, the micro-burner is set in motion toward the disc. If ignition occurs, which may be either a flash or sustained burning, the test is terminated. If not, the flame is brought to the edge of the disc and kept there for ten
Aerosol Flammability 225 seconds. If ignition still does not occur, record the result as negative. The can is then discharged to the 10% full level and retested. The remaining two test units are similary tested. The BAMA report does not suggest how the results might best be interpreted in terms of "Extremely Flammable" or "Flammable" criteria. The British aerosol community may have had concerns about the possible regulatory impact of any suggestions in this area. Foam Flammability Test Foam products are considered to comprise about 10% of the U.S.A. aerosol market, and as such should be candidates for flammability studies. They cannot be meaningfully assessed by the methods described thus far. In fact, the Sepro Can shave creams and similar products cannot even extrude the bulk of their hydrocarbon propellent, since it is contained in the so-called "exo-space", between the can and the inner plastic or aluminium container that holds the product. No particular furor has been raised by these methods shortcomings, and the most important reason is that no one consders shave creams, whipped creams and puffed lotion-type products to be flammable. When these products, which have 0 to 3.5% hydrocarbon propellent, are subtracted from the overall foam product category, there is really very litde mat is left. Flammable foams would include a few of the nonaqueous types developed by Kennedi Klausner during die early 1960s. A typical formulation would be: Non-Aqueous Aerosol Sunscreen Foam 1% Sun Screen Agent (As homomendiyl salicylate) 60% SD Alcohol 40-2 (Anhydrous) 30% Polyethylene Glycol 200 or 400 1% Non-ionic Fatty Acid Ester (Or polyox- yediylated fatty alcohol) 8% Propellent A46 Low-Aqueous Foam For Charcoal Ignition 75% Low-odor petroleum distillate; e.g. No. 1 Kerosene. 1% Selected non-ionic or anionic detergent system. 9% De-ionized Water 15% Propellent A46 A small number of minimum-water foams were also developed during die 1960s, such as those for igniting charcoal briquets in a grill or wood in a fireplace. One of diese is listed below at left. Other so-called flammable foams include die hydro- alcoholic, quick-breaking types such as suntan lotions, insect repellent lotions, body colognes and poison plant protectant creams (urushiol absorbants). The fully anhydrous types are further illustrated by such diverse products as baby oil foams, brilliantines, cleansing creams, frypan lubricants and spot-marking foams for farm or surveying operations. In die last instances, foams were produced from glycols and an edioxylated stearyl alcohol mixtures. They had the extraordinary ability to last many days, even under hot sunny conditions. During die 1960s researchers at Precision Valve Corporation developed die combination Tower and Through Test to define foam flammability. These procedures are described fully on Page 486 of diis handbook. The tower is used to define die relative amount of flammable vapors released by a foam during a certain period of time, while die trough is used to establish die degree of flammability of the foam surface. The trough mediod was adopted by die British Aerosol Manufacturers Association (BAMA) several years later, and appears in die latest edition of dieir Code of Practice (Fourth Edition, pg. 36, 1980). Nearly every hydrocarbon propelled foam product will produce a very transient, or fleeting, flame when die puff of foam is actually touched with a free flame. During 1960 die writer indulged in a bit of histrionics to convince die Commissioners of die City of New York Fire Department diat such foams were still eminendy safe. The demonstration consisted of spreading such a foam upon a relatively large portion of die face (to simulate a shaving routine) and dien touching die foam layer with a lighted match. No harm was done, but one of die clearest recollections of diis radier unusual experiment was how difficult it was to actually bring die lit match to the face, even with die psychological assistance afforded by a hand mirror. As in die case of die mediods developed to assess die flammability of surface sprays, no actual interpretive definitions for die distinction of extremely flammable, flammable or non-flammable foams were ever promulgated. Viable interpretations of the data in bodi die tower and trough procedures were developed by the CSMA Aerosol Division Flammability Committee, but
226 The Aerosol Handbook a legal opinion was obtained that the association should not publish such information. Any recommendations might be taken by regulators and possibly tightened, should they feel that official methods and definitions would be useful in this area. The BAMA trough method is also devoid of any interpretations of the data. Because of this development, plus the relative rarity of flammable foams, the test methods are almost never applied. In one rather interesting development, a low- aqueous charcoal lighter formulation initially gave a very tight, stable white foam. Despite the high (20%) hydrocarbon propellent content, it had to be actually contacted with a match or lighter flame for ignition. It burned rather controllably, "melting" into the charcoal briquets from the surface heat, and setting them afire in time. The product was shown to a particular marketer who wished to sell it, but strongly preferred that the foam be colored a canary yellow. A trace of tar- trazine dye was added for the desired effect. Test packs were initiated, but before they could age for more than a few months a substantial production was ordered, made and shipped. About six months later the firm began to be beseiged with an array of consumer complaints. The foam was marginally stable now, and produced gallons of flammable vapors. A typical report came from a customer who foamed a goodly quantity onto wet wood in a fireplace. When he tried to light the foam, the surrounding vapor/air mixture ignited with a "whoomp" type pressure wave, burning the hair from his forearm and blowing ashes from the previous fire onto the hearth apron and nearby floor area. An examination of the can confirmed information already demonstrated by the pre-production test pack units at this time: that the trace of dye caused the formula to become more active and dissolve enough polyvalent tin and iron from the dispenser that these ions could then significandy impair emulsion stability, changing an innocuous product into a relatively dangerous one. In this case, running foam flammability tests on new production units would not have served to indicate the hazard that developed later. Composite Flammability Tests For this approach the theory is that no individual test can satisfactorily elucidate the possible flammable hazard of an aerosol product. A combination of tests are needed. The first U.S.A. activity in this area suggested the use of three tests (and sometimes a fourth) to assess aerosol flammability hazards. As mentioned earlier, they were the Flame Projection Test, the Closed Drum Test and the Open Drum Test. The Lower Explosive Limit test was also used in the case of 100% propellent type products. The oudine of one version of this last test is given in the Propellent Chapter, in the discussion of dimethyl ether. The classical European definition of flammability: "45% or more of flammable ingredients, or over 250 g per can of these ingredients", is now being actively reconsidered since, without the CFCs, practically all anhydrous or near-anhydrous aerosol products will have to be classed as "Flammable". The rule has already been supplemented in Switzerland by the Flame Projection Test and Closed Drum Test. Both the FEA and individual European national aerosol associations have Flammability Committees now actively working on test methods. BAMA recendy finalized a flame extension, closed drum and surface residue method and submitted them to other aerosol associations worldwide, eliciting comments for possible improvement. A composite of flammability tests might include: a. Elaborations based upon one standard method. b. Independent use of two or more test methods. c. Colligative use of two or more test methods. In the first case, the method can be expanded by merely increasing the testing parameters. For example, the British feel that the flame projection test should be widened to consider if the aerosol spray will sustain the flame orice the ignition source is removed, and if a unit 90% emptied will have different properties than one 90% full. The second case is rather common. It has achieved prominence by virtue of official sanctions. The tests are run independendy and the results noted. The product is then considered flammable if either, both, or all methods give flammable results, depending upon how the regulation is written. In the U.S.A. if eitherthe flame projection or the flashback test is failed, the product is classified as "Flammable", but for definition as "Extremely Flammable" both the flashback and modified TOC flash point tests must be failed. The final approach involves the intermingling of two or more test methods to produce a final, more rational result than any of them would provide, taken individually. The essentials of the Rhone Poulenc Industries (France) four-test method have already been described.
Aerosol Flammability 227 A similar approach, but without the need for a statistical treatment, was promoted to the CSMA Aerosol Division Flammability Committee about 1976. It uses either a four or five component approach, depending upon the flammability level of the product, as shown by the worksheet in Table IX. At this time the committee was reasonably pleased with the regulatory situation, even though they deplored the shortcomings of the individual methods. They saw no reason for possibly upsetting the status quo. For those countries where the aerosol industry has matured, so have the flammability regulations. They have grown like a web, from agency to agency, to standard-setting institutions, state and local regula- Table IX Aerosol Flammability Results and Product Classification DORK SHEET M1VI DESCRIPTIONl •ACOUH CKIMP! _ nana, pressure (optional): initial delivery rate: J2B^. t»i-rt. at 70°F. gni./aac. at 70°r. Hark an "X" through tha dot ra- praaanting raeult in each test. TESTS t CALCULATIONS FLAME PROPAGATION at 70°F TEST 1: " TEST 2! TEST 3. FLASHBACK at 70°F. CLOSED DRUM TEST at 70°F. CALCULATION: a. x «/«. PERCENT PLAHMABLES (BY CALCULATION) IF OVER «>.X. FLASH- pomror flammables, (Hod. IOC) RESULTS aTaragt ».* °r. TEST CRITERIA 0" 0»ar 0" to 18" 0»«p 18" to 2V' Oaer JV. 0" Ow 0" to 3" Oaer J" to 5" Ovar 5" to 6" Total diapenaer Ow 120 g. Ow 60 to 120 g. Ow 30 to 60 g. Omr 0 to 30 g. 0 to l».5v.X Ow 4.5 to *5 V.X Over 43 to 100 V.X Orap 212°F. Ow 100 to 212°F. Orar 20° to 100°F. 20°F. or laaa SPRAY CLASSIFICATIONS Non-FJ None a a • a . a • • Comb. • • • , • • Slain. • • — • _... • E,.r. • • • .. • DO ROT FILL OUT fOLLCMIHO SECTION IF SPRAY IS MOK-FLAKHABLE OB EXTREMELY FLAMMABLE. TESTS SURFACE FLAMMABILITY FORMICA Ho flaa* (-) _ Hoaantary flaao(+) t_ Sustained flam <♦+) COTTCK CLOTH Ho flaM (-) _ Mtmaatary fla»a(+) Stutainad flaaa <♦♦) "~ RESULTS Total nuabar of U) ■arka. TEST CRITERIA No (+) Mrice. On« O) Bark. Two or nor* (+) ■arka. RESIDUE CLASSIFICATIONS Kone • Comb. • Fla». • 8pr«7 ia claaalflad according to hlghant laval of flaaaabilit; In any ona taat, axcept that "Extpeaaly Flaianabla" raqulraa two auch taat ratlnga. Raaldua ia elassiflad ae highaat laval of flaaaiabillty in any ona taat. SPRAI CLASSIFICATION RESIDUE CLASSIFICATION tions, importation rules, international transport interpretations and so forth, until by now they are virtually immutable and permanently fixed adornments of what may be called "the system". Modest additions or refinements might be contemplated, but deletions would be incredibly hard to implement. Some will recall that the ICC deleted their Open Drum Test about twenty years ago, and despite this, the method still shows up in the protocols of testing laboratories, state regulations and briefs filed by certain consumer groups. For those firms interested in exporting or importing aerosols, it is important to recognize that the methodology and interpretation of results for the various flammability tests will differ from country to country. For instance, the closed drum tester varies from 11 gallons (50 liters) in Japan to 40 gallons (150 liters) in England to 55 gallons (200 liters) in the U.S.A. The first uses a spark plug, the second a candle near the roof of the drum, and the third a candle at the floor of the drum. Aerosols are equilibrated to 77°F (25°C) before testing in Europe and to only 70°F (21.1°C) prior to testing in the U.S.A. The drum test is recorded in terms of g/1 in Japan, g in England and s in the U.S.A. Exports to other countries should be tested in accordance with their test methods, and the products labeled as per their interpretations and required precautionary language, type size, placement and so forth. To fail in this area can be extremely expensive, since products may simply be impounded at dockside. Complete documentation for any foreign country can generally be secured by writing to their embassy or to the appropriate aerosol association. Electrostatic Flammability Hazards Static electricity is a phenonmenon of nature that affects every moving substance. The effects of static discharge can vary from huge lightning bolts to such subtle changes that they can be detected only by the most sensitive instruments. In the aerosol industry, (as in the electronics industry and others) the greatest problem with static is caused by the development of tribo- electric charges. These charges are generated whenever two materials in direct contact are separated. One of the materials, called the host substance, tends to strip electrons from the other, called the donor substance. For example, a person can generate 25 to 50 volts (V) merely by waving his or her hand in dry air. The simple act of taking off a sweater or cotton tee-shirt can create localized charges of up to 10,000 V in dry air. If the
228 The Aerosol Handbook room is darkened at the time, blue flashes of static electricity will be quite visible within the garment. Materials differ widely in their ability to become positively or negatively charged. Table X provides such a comparison for a modest number of common materials. Conductivity is a key factor in static electricity considerations, since conductive materials are able to dissipate more quickly a charge and also to release electrons more easily to a less conductive host substance. The relative humidity, and the ability of materials to absorb moisture are both important aspects of conductivity. In the aerosol field, triboeletric charge became important about 1977, when it was discovered that certain products, formulated from either CFC or hydrocarbon propellents, were able to generate a profound electrical charge if the dispenser was leaking rapidly at a time when they were electrically insulated. But with the hydrocarbon propellents, the situation was potentially more serious. If the accrued energy was sufficient, the Table X Triboelectric Table of Common Substances Air Human hands Asbestos Animal fur Glass Mica Human Hair Nylon Wool Lead Silk Aluminum Paper COTTON Iron and steel Wood Amber Stainless steels Sealing wax Hard rubber Nickel, copper and brass | Easily becomes positively charged. Can become positively charged. Reference Can become negatively charged. Silver, gold and platinum metals Sulfur Acetate (as rayon) Polyester Celluloid Orion Saran Polyurethane Polyethylene Polypropylene Polyvinyl Chloride (PVC) Kel-F Silicon Teflon Easily becomes negatively charged. hot spark that resulted when the container discharged onto a conducting surface could cause the ignition of any flammable contents remaining in the can. Such cans sometimes turned into erratic flame-throwers. Somewhat lower voltages (ranging from about 75,000 to 200,000 V) have been recorded in the case of perfumed after-bath talcum powder sprays, dry powder antiperspirants and regular antiperspirants of both the 70% hydrocarbon and 90% CFC varieties. Liquids were generally in the 0 to 4,000 V range, although exceptions have been noted. For example, P-12 was tested at 920 V and P-152a gave a 25,800 V reading. For any of these voltages to accrue, the cans had to be electrically isolated. In normal consumer spraying, the charge is distributed over the human body, which eliminates any build-up and thus any possible hazard. For some of the absorbent powder cleaning products, depending upon humidity and use conditions, a slight electrical tingling of the hand might result from extended spraying, but this was of no marketing significance. When an aerosol can is sprayed or punctured, the product cloud emerges with a total charge Q_ (which may be either positive or negative) and the can, assuming it is electrically isolated, is left with an equal charge of opposite sign. The charge on the dispenser itself may not be a uniform one; for instance, the plastic actuator and the metal can may be quite different. In some cases, the dispenser will build up a charge of a particular sign and then, anywhere from perhaps 2 to 30 seconds afterward, the charge will diminish, pass through the zero point and grow into a sizable one of the opposite sign. The cause appears to be a spatial redistribution of charge in the product remaining in the can, as powders setde and as the charge percolates with difficulty into essentially non-conducting formulas. Electrical charge Q_ is measured in coulombs (given as C in the new International System of Units, ISO Standard 1000) and is a quantity of electricity. It may be measured with a Keithley Model 610C electrometer, operating as a high (1014 ohn) input impedance unit gain amplifier. For best results, the output is read from an attached Keithley Model 173 4-J4 digit digital multimeter. These are expensive instruments, and their cost has limited the determination of electrical charge to a small number of firms, such as the Phillips Chemical Company and E.I. duPont de Nemours & Co., Inc. The charge Qwas determined originally by positioning the aerosol can within a so-called '' Faraday pail'': a metal container about 8 " (200 mm) in diameter and 12 "
Aerosol Flammability 229 SCHEMATIC DIAGRAM ELECTRICAL DIAGRAM Q = CHAJiGL C = CAPACITOR (CONDJJNSUR) V = VOLTAGL Figure 10. Apparatus for Measuring Static Charge on Aerosols (300 mm) high. The can is insulated from the pail, by setting it on a styrofoam base, and the pail is likewise isolated electrically by positioning it on a block of styrofoam. The physical and electrical schematics are shown in Figure 10. The can and pail constitute a capacitor: a device for accumulating and holding a charge of electricity, since they form two equally charged conducting surfaces separated by a dielectric of plastic. The capacitance is identified as Cx. The pail, in turn, is connected to a ground via a capacitor of certified known capacitance, Cm. Capacitance is measured in microfarads, or /iF, and a typical value for Cm would be about 0.05/tF. To determine Cx, which varies from can to can, two or three special dry cell batteries, used in photography, are purchased which have voltages in the 225-250 V range. They are series connected to the aerosol can. The Keithley is then used to determine Q, which is equal to CmVm. From this, Cx is determined from: cx = cmvm vb If Cm = 0.05/tF and the charge Vb is 720 V from three batteries, a Keithley reading of Vm = 100 mV would relate to a Cx value of: C = 0.05mF x O.lOOv 720 v Cx = 0.0694/tF x 10 -* = 6.94pF (Picofarads) The reading of about 7 pF is typical for a 202 x 406 can containing 4 Av.oz. (113.4 g) of product, but the range for this example varies widely: from about 4 to 11 pF. Conversions to 202-diameter cans of other heights are made according to the height ratio. For example, a 202 x 509 can is 25% taller than the 202 x 406 unit, so the typical capacitance should be about 7 x 1.25, or 8.75 pF. The much larger 211 x604 can with a 10 Av.oz. (283.4 g) fill will show an average capacitance of about 15 pF. with a range of about 11 to 22 pF. For comparison, the human body has an average capacitance of about 75 to 300 pF. Now that the capacitance Cx is known (or estimated), the can may be tested for charge development when sprayed or punctured. The can is positioned on an electrically isolated support and connected to the positive lead of the Keithley. It is also connected to the Keithley negative lead via a capacitance of known value, generally in the range of 1,000 to 100,000 pF. The negative lead is also grounded, and the ground wire connected to the support base that will receive the released aerosol product. The maximum coulombs developed by the aerosol is read from the electrometer. This value is then used to determine both voltage and charge. To determine voltage V the equation: y _ Q (charge in coulombs) C^capacitance in farads) is used. If we assume the measured value of Qis 8 x 10-7 coulombs and the capacitance of the aerosol can is 7 pF, solving for V gives: v =8x10-% . 114,000 7 x 10-12 To determine energy W, the equation: \y = Q2 = coulombs2 2CX 2 x farads is used. If we use the mentioned values again for Qand Cx, solving for W gives: W _ (8 x 10-7)2 = 0.046 joules 2 x 7 x 10-12 W = 46 millijoules (mj) Using the Cx value of 7pF, the values for voltage, electrostatic charge (Q) and sparking energy (W) can be linked together for a number of chemicals or aerosol compositions. Table XI (Page 230) lists typical data.
230 The Aerosol Handbook Although the "Faraday Pail Method" of static charge measurement is useful for indicating the electrical relationships involved, it must be considered only as an interim procedure, replaced with much superior methods as the investigations continued. It probably will not be used any further by the aerosol industry. The currently (1982) preferred method is the "Direct Charge Method", such as the one developed recently by a CSMA Aerosol Division task force and proposed for inclusion in the CSMA Aerosol Guide. The method involves the direct connection of the test can, puncturing device and insulating stand to the Keithley electrometer. After a standardization step using a capacitor of known value and a flashlight battery, 'Punctured can became empty at about 16 seconds. The Simco Electrostatic Locator appeared to have a lag time of about five seconds. where the measured charge should equal the calculated one, the equipment is set to determine the aerosol charge upon puncturing. The can is punctured and the maximum coulombic charge is recorded. This value can then be used to calculate both voltage and energy. Further information cannot be given since the test method is unpublished proprietary information in the care of CSMA at this time. It should be published in the CSMA Aerosol Guide by 1983. Other devices, such as the Simco Electrostatic Locator, may be used, and also other experimental techniques, such as the Screen Test Apparatus, jointly developed by Calspan Corp. and a major U.S.A. marketer. As Table XI shows, there are wide variations The product contained about 10% powder (mainly talc), 15% ethanol and 75% A-31. Table XI Electrostatic Charge, Voltage and Sparking Energy for 202 x 406 Cans of Several Aerosol Products (Assume dispenser capacitance Cx = 7 picofarads.) Aerosol Product P-12 P-114 P-12/11(50:50) P-142b P-152a Isobutane A-31 Perfumed Talc No. 1 Perfumed Talc No. 2 Antiperspirant P-12/11 Absorbant Silica Spray (50:50) Voltage (kV) 0.375 - 2.00 0.080 - 2.80 8.0 (typical) 4.60 - 10.00 3.15-9.950 0.12-0.300 123.0 (typical) 110.0 (typical) 95.0 (typical) 285. (typical) Electrostatic Charge (Q, in + or - coulombs x 10"7) 0.0263 to 0.140 0.0056 to 0.196 0.560 0.322 to 0.700 0.221 to 0.697 0.0084 to 0.021 8.60 7.71 6.65 20.0 Sparking Energy (W, in mj) 0.0005 to 0.014 0.00002 to 0.027 0.224 0.0741 to 0.350 0.0349 to 0.348 0.00005 to 0.00032 52.8 42.4 31.6 286. Flammable products developing over 4 kV or 0.15 mj may be dangerous in production, unless precautions are taken. Table XII Variation of Electromotive Force (Voltage) When an Aerosol is Sprayed and/or Punctured Elapsed Time (seconds) 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 Can A 100% Full Sprayed 0 100 800 1600 2000 2300 2400 2450 2450 2450 2450 2450 2450 2450 2400 Can A 50% Full Sprayed 0 100 600 1400 2100 2700 2800 2700 2200 1600 800 -200 -800 -1450 -1500 Can A 15 % Full Sprayed 0 100 950 1750 2000 1600 800 50 -600 -900 -1050 -1150 -1200 -1300 -1400 Can B 100% Full Sprayed 0 100 600 1250 1650 1950 2300 2650 2950 3300 3500 3450 3500 3450 3400 Can B 50% Full Sprayed 0 100 750 1500 1750 1950 2100 2200 2250 2150 1700 1000 200 -800 -1200 CanC 100% Full Punctured 0 250 1750 3400 3250* 3300 3300 3300 3300 3300 3300 3250 3250 3250 3250
Aerosol Flammability 231 in triboelectrification results, even for single liquid propellents. Aerosols take various periods of time (usually less than a minute) to achieve a steady charge state when sprayed. Sometimes they never do, but change continuously. An example is shown in Table XII. Powder-containing aerosols often develop higher charges and energy when sprayed, compared to puncturing. In addition, they usually develop opposite polarities, depending upon whether they are sprayed or punctured. In a few cases, the polarity may reverse twice during spraying. No really satisfactory explanation has yet been advanced to account for these observations. It is important to note that the capacitance Cx relates not just to the aerosol can, but to the combination of the can and surrounding Faraday pail. If the position of the can is changed within the pail (such as off-centering it, or raising it partly outside the pail) the value of Cx will change. By removing the surrounding metal, or making it more remote, the capacitance of the aerosol can decreases and its energy increases. In one instance, this consideration may have become very important. A can of powder-containing product, with only a modest ability to develop a charge, was sent to a can company for test pack evaluation studies leading to a one-year warranty. After six months of storage, the can was punctured inside a well ventilated hood and the rather messy contents directed downward into a soapstone sink with running water splashing about. The hard water effectively grounded the entire surface of the sink basin to the plumbing fixtures. When the can was incidentally brought close to or possibly against the sink ledge a spark leapt and ignited an explosive isobutane/air mixture within the sink and (to some extent) in the hood as well. The operator was moderately burned on both hands and slightly burned about the face. Companion cans were tested and found to have voltage maxima in the range of 2250 to 4400 V. For quite a long time aerosols that developed polarities of over about 4000 V were considered hazardous from a triboelectric viewpoint. This rule of thumb has turned out to be a good one, although it is now recognized that some flammable gases require much less energy to ignite than do others. That energy, which in this context may be called sparking energy (W), must be at least about 0.15 mj (millijoule) for ignition. However, some gases may not ignite until a spark of perhaps as high as 0.25 mj is attained, this type of situation can be crudely illustrated in the closed drum test, where the sparks from smaller sparking devices (Tesla coils, etc.) were sometimes found to possess insufficient energy for ignition of the gas/air mixture. A higher spark energy is also required to provide ignition of LEL and UEL gas/air mixtures, compared with those well within the flammable range. The relationship of capacitance Cx to electrostatic charge, voltage and sparkling energy is shown for threshold situations in Table XIII and Table XIV. Precautions Against Triboelectric Ignitions A number of approaches may be used in the control of static charge problems. Perhaps the first is preventive formulation development. Alternately, safeguards should be applied to the production process to minimize hazard development. Related considerations also apply to the disposal of unwanted cans. Reformulation The adjustment of formulations to reduce or eliminate triboelectric ignition hazards is a difficult Table XIII Relationship of Capacitance, Electrostatic Charge, Voltage and Sparking Energy in the Threshold Ignition Area Container Size Capacitance Cz (picofarads) Electrostatic Charge, Q(coul.) Voltage V (volts) Sparking Energy, W Small Medium Large Small Medium Large 7 10 15 7 10 15 4.58 x 10"8 5.48 x lO"8 7.08 x 1CT8 5.29 x 10"8 6.32 x 10"8 7.75 xlO'8 6,540 5,480 4,720 7,560 6,320 5,170 0.150 mj 0.150 mj 0.150 mj 0.200 mj 0.200 mj 0.200 mj *Some readily ignitable gases will burn when impacted by a spark with this level of energy. 'Many flammable gases will ignite when impacted by a spark with this level of energy. Aerosols that develop 4,000 V or less when sprayed or punctured will almost never self-ignite from spark generation.
232 The Aerosol Handbook business. The additives needed to reduce charge are often incompatible, or may represent a significant cost increase. Also, they may be unreliable, so that one can is non-hazardous but a second one is. If a product develops a potential of 4 kV in less than four seconds after spraying or puncturing it should be considered possibly hazardous. The same can be said of dispensers developing sparking energies of over about 0.15 mj in four seconds or less. As these ratings increase, so does the probability of hazard, should appropriate conditions arise. Where ratings are very high, the chance of reducing potential and energy values to essentially safe ranges becomes a virtually impossible task. The addition of water generally decreases triboelec- tric hazard, but 2 to 3 % must often be added to be effective. The addition of solids can reduce charge in the presence of polar liquids, such as ethanol and water, but will increase it greatly in the case of non-polar solutions. Surface active materials, such as non-ionic and cationic detergents, will often reduce hazard. Propylene Table XIV Minimum Ignition Energy of Various Substances Material Lead (II) Azide Hydrogen Carbon Disulfide Mercury (II) Fulminate Cyclopropane isoButane n-Pentane Benzene n-Hexane n-Heptane Gasoline Ethane Propane Methanol n-Butane Methane Acetone Aluminum Powder Ethanol Nitrocellulose (13.4%N) Trinitrotoluene (TNT) Ammonium Perchlorate Minimum Ignition Energy (millijoules) 0.01 (min.) 0.02 0.02 0.03 (min.) 0.18 0.20 0.20 0.21 0.23 0.24 0.25 0.25 0.25 0.25 0.26 0.29 0.60 0.60 (min.) 0.65 62.0 62.5 6150. Courtesy of Julie Associates, Inc. (Billercia - Pinehurst - MA 01866) A larger listing involving 56 flammable gases and vapors is provided in Electrostatic Hazards by Heinz Haase (translated by Michael Wald), Verlag Chemie, Weinheim and New York (1977). Data are taken in air mixtures at 1 bar absolute and 20°C. glycol and sometimes glycerin are effective in non-polar environments. Metallic stearates and similar compounds sometimes help. Rough measurements of charge development can be made with equipment costing less than $1,000, but when a final product is developed and thought to be acceptable, it is a good idea to have it tested by an industry supplier or a consulting firm with the proper equipment to obtain a fairly reliable answer. The Calspan Corporation and Hercules Powder Company can do this work. Consultant services are freely supplied by The Simco Company (Lansdale, PA 19446), Electro-Tech Systems, Inc. (Glenside, PA) and the Static Control Systems group, 3 M Company. Production Precautions When a potentially hazardous product is to be run, the gassing equipment should be checked carefully, more than usual, striving to eliminate the chance of star-wheel jamming. Dead plates between live conveyor sections should be flat and smooth. Top cylinder seals should be checked for hydrocarbon leakage. And the synchronism of head release and out-feed mechanisms should be looked at to prevent tilting and jamming at the gasser. The exit of valve button tippers is another sensitive area that should be checked. If no production or rate difficulties are anticipated, the T-t-V (through-the-valve) gasser is preferred over the U-t-C (under-the-cap) variety. It is more problem- free. The cans should be grounded at all times, unless they happen to be flipped from the line as a result of a jam-up. Can grounding starts with the grounding of all the associated production equipment. One or two deep- earth grounding pipes, driven at least 10 ft (3.05 m) into the soil, are required. They are connected to some spot on the line, such as a conveyor section. Each piece of equipment is then grounded by a double, heavy copper wire connection to the piece on either side, so that the entire line is then grounded. The cans should be in contact with the metal of the production line at all times where jamming or puncturing could occur, even if this means the replacement of Delrin fixed can handling parts with conductive materials, using stainless steel conveyor rails instead of nylon, and changing plastic conveyor belts to metal linkages. Kartridg Pak Company and other machine suppliers now offer these alternates. As an available option, the starwheel (notched wheel) and guides at the exit of the gasser may be made
Aerosol Flammability 233 of conductive plastic, such as Velostat Series 3000, by the 3M Company, this material is also made as an adhesive-backed 8 mil (0.2 mm) film — Velostat No. 1758. Some firms have used bronze "whiskers" along critical parts of the conveyor system to dissipate the charge from any punctured cans caught between plastic rails. Additional precautionary measures have been proposed, but they are considered to be of value only if there are doubts that the aerosol can will always be in contact with a conductive surface. They can be conveniently listed as: a. Apply a steam jet to the gasser heads and exit star- wheel area to "wet lubricate" moving parts and improve conductivity. Note: High humidity does not stop the generation of static or ignition of flammable mixtures from a hot spark, but it can prevent the accumulation of static charge. b. Direct a stream of ionized air at problem areas after the gasser, using a #907 Ionized Air Source from the 3M Company, or comparable equipment, in conjunction with a low-pressure air supply. c. Monitor sensitive areas with static detection equipment. Note: Typical equipment is the Sim- co Electrostatic Locator, Types SS-1 (The Simco Company, Inc.) Operation is difficult and requires special knowledge — see Simco instructions. Accessories are needed for full scanning, such as determination of charge on cordlike belts used on some weighcheckers. Where plastic moves on some other surface, potentials up to 20 kV have been measured and sparking can be seen in a darkened room. d. The use of beryllium copper will reduce mechanical sparking by about 98%. However, these sparks are never sufficiently energetic to ignite gas/air mixtures. The purchase of very expensive, relatively soft beryllium copper tools for gas houses must be questioned. e. Use conductive materials to ground employees in sensitive areas. Floors can be made of concrete containing a grounded copper surface grid, or of ceramic tiles containing enough iron (III) oxide to provide a low conductivity. Such tiles are made by the Winburn Tile Manufacturing Company (Little Rock, AR) and other firms. Rubber floor mats should not be used. Wetted floors are more conductive. f. Discontinue the use of synthetic clothing for employees, such as polyesters. Use cottons, woolens and leather soled shoes. g. Direct a mist or small stream of tap water at critical surface areas to wet them down and improve conductivity. h. After one punctured can produced a 7 ft (2.13 m) horizontal lance of flame that narrowly missed a nearby operator, the firm erected a clear plastic barrier in that area of the line. i. Another firm identified a substantial charge development on a 30 gallon (114 liter) metal drum, used in the gas house to hold leaking or otherwise defective aerosol cans. The drum was on an oak pallet for easy transport, and thus electrically isolated. They now clip a grounding wire onto such refuse drums before using them. j. One company had a threesome of punctured cans cause a brief but very hot fire surrounding the U-t-C gasser The propellent hoses were damaged and had to be replaced. The original hoses were of standard nylon core, polyester braid and polyurethane jacketed, with a working pressure of 2250 psi (15.5 MPa). The firm now uses Synflex hoses with an additional outer jacket made from an asbestos-ceramic compound. Working pressure remains the same. k. Another concern had a can puncture initiate a fire in the U-t-C gasser area and the machine developed large secondary fires from leaking seals. After extinguishment, all worn or damaged seals were replaced and the maintenance program was intensified. 1. High tribophoric aerosol products may not only cause spark-initiated fires when the can is punctured, but also when defective crimps are produced (bady cocked cans, non-centered, dimpleless valve cups, etc.) and where valve area leakage is caused by such things as a missing spring and a stress cracked mounting cup. These causes can be reduced by machine maintenance and heightened inspection levels. Potentially dangerous aerosol products should always be grounded when deliberately punctured dur-
234 The Aerosol Handbook ing both mechanical and manual disposal operations. For example, a serious fire in an outside area injured a laboratory technician when she attempted to puncture a small number of antiperspirant aerosol units without grounding them first. Due to space limitations, coverage of this interesing subject has been brief. Additional data can be gleaned from the National Protection Association (NFPA) Fire To this point we have discussed only the flammability aspects of single aerosol units, but the scope of aerosol flammability extends also to considerations of safe manufacture and storage. These aspects have become particularly important during the period from about 1977 on, when the industry was forced to rely upon hydrocarbons as the predominant propellent type. The first major testing of aerosol flammability under simulated warehouse conditions was begun by the Factory Mutual Engineering Corporation (FM) in 1979 and led to results, conclusions and recommendations of concern to the industry. As. a result, a cooperative program with FM has been funded by industry for further testing, and this may not be concluded until about 1983. These larger-scale flammability aspects are covered here in detail. Safe Handling of Aerosol Concentrates The transition from CFC to hydrocarbon propellents has not had a significant effect upon the composition of aerosol concentrates, but the growing industry commitment to overall plant safety, brought on by the increased use of hydrocarbon gas liquids, has acted to improve the manufacturing conditions under which the concentrates are produced. Stated more direcuy, there was little point in investing up to millions of dollars for the safe utilization of hydrocarbons, if a serious fire in a relatively unsafe liquid compounding operation could burn down the plant. Of the plant and warehouse fires that have directly affected the aerosol industry during the past ten years or so, hydrocarbon gas liquid types are by far the most Code, 1977 issue, Volume 4, Chapter 56A, as well as Part IV, Sec 46. Also, the BAMA Electrostatics Panel produced a manual titled General Guidelines for the Safe Handling and Disposal of Powder Containing Aerosols" (1980); and finally, special reports such as the Aerosol Age (March 1979) article titled "Measuring In-plant Electrostatic Charge" by Reusser, R.E., et al of Phillips Petroleum Company should be of interest. common, being perhaps 60% of the total. Aerosol concentrate fires and warehouse storage fires account about equally for the remainder. The usual cause of a concentrate fire is the ignition of a flammable vapor/air mixture by an electric spark. Two classes of sparks may be involved: those from the commutator area of an electric motor or from an electric switch, and those generated by static electricity. The ignition of flammable powder/air mixtures is very rare (only one small instance known), and ignition from free flames is also very uncommon. The two substances most commonly involved in aerosol concentrate fires are ethanol and relatively volatile petroleum distillates. Ethanol has a Tagliabue Closed Cup (TCC) flash point of 55°F (12.8°C). A typical, fairly volatile petroleum distillate used in many furniture polishes and other products, consists of a blend of mainly isoheptane and isooctane and has a typical TCC flash point of 39°F (3.9°C). Since these flash point temperatures are usually below ambient, the mere act of striking a match near the top of a tank containing either solvent could result in a disastrous fire. In fact, the situation is made even more critical in that the stirring and possible vortexing of these liquids acts to wet the walls of the tank and create a miasma of vapor and tiny liquid droplets in the head space, making the tank more susceptible to content ignition than might be anticipated from the temperature of the liquid. Heating ethanol is not recommended except in a completely closed, pressure-tight vessel. The same comment applies to petroleum distillates all the way up to the kerosenes and even mineral seal oils. As a rule, Next Page AEROSOL FLAMMABILITY IN PLANTS AND WAREHOUSES
234 Previous Page ing both mechanical and manual disposal operations. For example, a serious fire in an outside area injured a laboratory technician when she attempted to puncture a small number of antiperspirant aerosol units without grounding them first. Due to space limitations, coverage of this interesing subject has been brief. Additional data can be gleaned from die National Protection Association (NFPA) Fire The Aerosol Handbook Code, 1977 issue, Volume 4, Chapter 56A, as well as Part IV, Sec 46. Also, die BAMA Electrostatics Panel produced a manual tided General Guidelines for the Safe Handling and Disposal of Powder Containing Aerosols" (1980); and finally, special reports such as die Aerosol Age (March 1979) article tided "Measuring In-plant Electrostatic Charge" by Reusser, R.E., et al of Phillips Petroleum Company should be of interest. AEROSOL FLAMMABILITY IN PLANTS AND WAREHOUSES To diis point we have discussed only die flammabil- ity aspects of single aerosol units, but die scope of aerosol flammability extends also to considerations of safe manufacture and storage. These aspects have become particularly important during die period from about 1977 on, when die industry was forced to rely upon hydrocarbons as die predominant propellent type. The first major testing of aerosol flammability under simulated warehouse conditions was begun by die Factory Mutual Engineering Corporation (FM) in 1979 and led to results, conclusions and recommendations of concern to die industry. As, a result, a cooperative program with FM has been funded by industry for further testing, and this may not be concluded until about 1983. These larger-scale flammability aspects are covered here in detail. Safe Handling of Aerosol Concentrates The transition from CFC to hydrocarbon propellents has not had a significant effect upon the composition of aerosol concentrates, but the growing industry commitment to overall plant safety, brought on by the increased use of hydrocarbon gas liquids, has acted to improve the manufacturing conditions under which the concentrates are produced. Stated more direcdy, there was little point in investing up to millions of dollars for the safe utilization of hydrocarbons, if a serious fire in a relatively unsafe liquid compounding operation could burn down the plant. Of the plant and warehouse fires that have directly affected the aerosol industry during the past ten years or so, hydrocarbon gas liquid types are by far the most common, being perhaps 60% of the total. Aerosol concentrate fires and warehouse storage fires account about equally for the remainder. The usual cause of a concentrate fire is the ignition of a flammable vapor/air mixture by an electric spark. Two classes of sparks may be involved: those from the commutator area of an electric motor or from an electric switch, and those generated by static electricity. The ignition of flammable powder/air mixtures is very rare (only one small instance known), and ignition from free flames is also very uncommon. The two substances most commonly involved in aerosol concentrate fires are ethanol and relatively volatile petroleum distillates. Ethanol has a Tagliabue Closed Cup (TCC) flash point of 55°F (12.8°C). A typical, fairly volatile petroleum distillate used in many furniture polishes and other products, consists of a blend of mainly isoheptane and isooctane and has a typical TCC flash point of 39°F (3.9°C). Since these flash point temperatures are usually below ambient, the mere act of striking a match near the top of a tank containing either solvent could result in a disastrous fire. In fact, the situation is made even more critical in that the stirring and possible vortexing of these liquids acts to wet the walls of the tank and create a miasma of vapor and tiny liquid droplets in the head space, making the tank more susceptible to content ignition than might be anticipated from the temperature of the liquid. Heating ethanol is not recommended except in a completely closed, pressure-tight vessel. The same comment applies to petroleum distillates all the way up to the kerosenes and even mineral seal oils. As a rule.
Aerosol Flammability 235 heating ethanol is useful only in speeding up the dissolution of solid hair spray resins and similar additives, which will go into solution at room temperature if given a little more time. But in the case of the isoparaffinic and similar petroleum distillates, it is often necessary to heat the oil-phase to about 170°F (77°C) before combining it with a water-phase to make various emulsion type concentrates. Ideally, this potentially dangerous step should be conducted in a closed tank with two or three intakes of an efficient exhaust system located below the side wall area, and with no electrical equipment within at least 30 feet (9.1 m) unless it is explosion-proof. The tank should not be opened until the completed emulsion has been jacket-cooled to 100°F (37.8°C) and preferably below. The relatively volatile isoparaffinic solvents, VM&P napthas and similar petroleum distillates are considered more dangerous than ethanol. They have lower flash points as a rule, form flammable vapor/air mixtures with less than 1 % vapor (ethanol has an LEL concentration of 3.28%), and have vapor densities of typically 3.5 to 4.0 compared with air. Ethanol is only 1.6 times as heavy as air. A heavy vapor has the capability of traveling a good distance along a floor, drainage channel or other surface — possibly to a remotely located ignition source. A travel distance of over 250 feet (76 m) has been authenticated in the case of a hydrocarbon vapor. When ignited, hydrocarbon vapors produce relatively smoky fires. Burning hydrocarbon liquids are also far more difficult to extinguish than ethanol fires, because they are insoluble in water. They may even form burning layers on the surface of the water, which act to carry the problem into other areas of the facility. Other flammable chemicals have been implicated in aerosol fires, either in the compounding area or filling area. They include diethyl ether, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), methanol and isopropanol (IPA). all these liquids are volatile and have TCC flash points of about 60°F (15.6°C) or below. Several contract fillers have turned down potential business involving these solvents (especially diethyl ether) on the basis that they felt the level of flammablility risk was unacceptable for their production facilities. In one instance, after settling a major claim, an insurance company advised a filler that they would no longer insure his plant if he continued using any volatile liquid petroleum distillates. The primary defense against concentrate fires is ventilation. Exhaust registers should be located near tanks used for compounding flammable concentrates, preferably below the rim, to suck up any vapors escaping from the top. Larger plants may have very large exhaust systems, with main trunks of sheet metal construction measuring as much as 4 x 4 feet (1.22 x 1.22 m) in cross-section. They remove air to the outside so rapidly that adequate heating of the compounding areas can be very difficult during the cold winter months. Direct ventilation by the use of explosion-proof fans can be used to diffuse relatively concentrated and possibly flammable vapor/air mixtures so that they become harmless through dilution with more air. This approach is suitable if the mass of generated vapor is relatively small in comparison with the size and air transfer rating of the enclosure. Some fillers leave large doorways open during the summer, to provide cross- ventilation. This may be useful as a back-up precaution, if a good breeze is blowing in the right direction, but only to that extent. The escape of flammable vapors can be minimized by closing over the tops of compounding and holding tanks, keeping hatches shut when not in use for additions or observations, and monitoring the introduction of chemicals to tanks so that dangerous spill-overs will not happen. In one case, a hair spray concentrate overflowed a 4,000 gallon vertical holding tank, and the alcoholic mixture festooned downward onto a plywood enclosure literally covered with switches on both the inside and outside walls. Fortunately, nothing happened — except that the plywood cubicle was dismantled and the banks of switches mounted in a more remote location. Flammable liquids and gases are unforgiving: if a flammable vapor contacts an ignition source, it will catch fire. Fortunately for the aerosol industry, very few formulations are prepared by adding finely divided potentially flammable powders to liquids. Many chemical manufacturers deliberately produce flammable or combustible solids in macro forms: prilled, pelleted or coarse granules, for the safety of both their own employees and those of their various customers. Starch powders are often added to hot water to produce starch concentrates, but the humidity helps to moisten the paper bag and drain away any possible charges. An example with far more potential for static-induced flammability would be the addition of powdered pharmaceutical compounds to ethanol, especially if they are contained in polyethylene bags. Plastic bags
236 The Aerosol Handbook are notoriously difficult to ground, since they are so non-conductive. For this kind of work, employees should be grounded by means of wrist straps, shoe straps or conductive floor mats. Further protection is afforded by the use of the 3M Company's "907" Ionized Air Source or a similar device. In the "907" (which is really only a nozzle) a circular strip of Polonium 210 ionizes up to 75 CFM (35.4 liters/s) of air. This is sufficient to reduce a static charge of 25 kV to zero in less than one second at a distance of two feet (0.61 m). The polonium is an alpha emitter, but these particles cannot even penetrate the epidermous layer of skin and are thus regarded as harmless. The isotope has an effective life of one year, and the equipment is leased for that period of time. The ' '907" nozzle must be connected to a suitable air blower system. Ethanolic concentrates have caused a large number of so-called filler fires over the years, possibly caused by sparking micro-switches, static charge or other ignition sources. Remembering that only vapors burn, many fillers position air-circulating fans near the filling machine to remove flammable vapors and, incidentally, hasten the evaporation of any spilled liquid product. Safe Handling and Gassing of Hydrocarbons A great deal of specific information has been amassed by experts into such books as the "CSMA Recommendations for the Safe Handling and Filling of Hydrocarbons in the Plant and Laboratory" and such equivalent volumes as those by the British Aerosol Manufacturers Association (BAMA) and Aerofill, Ltd. In addition, such circumspect firms as Gillette and Unilever have developed safe practice guides, guidelines and checklists for audit and inspection, to make sure their aerosol products are produced in conformance with recognized safety standards in the use of hydrocarbon propellents. Finally, a number of seminars have been held in both die U.S.A. and Europe, under the auspices of trade associations interested in providing aerosol people with information regarding die safe use of these gases. Because of diis, our treatment here is limited. There are two key segments of any installation using hydrocarbon propellents: the unloading, storage, pumping and piping system, and the gassing room. Fires have occurred in both areas, aldiough the ones within die gassing enclosure are almost always die more serious. Unloading, Storage and Handling System Since hydrocarbons are delivered in tanktrucks of up to 8,000 gallon (30,280 liter) capacity and in tankcars of up to about 30,000 gallon (113,600 liter) capacity, the minimum tankage for any filling plant will be about 10,000 gallons (37,850 liters). Permanent storage tanks in the 10,000 to 30,000 gallon range must be located not less than 50 feet (15.24 m) from property lines and important buildings. Tank truck and/or tankcar unloading stations should be at least 10 feet (3.05 m) from the tank. Both storage tanks and associated equipment should be maintained in a fenced area with two emergency exits. The land should be kept free of grass and weeds and should have no low spots. Air should move freely across it to disperse any possible vapors. Shut-off valves at the tank should be accessed readily, even in the unlikely event of a fire at die propellent pump. Safety relief devices on the tank should have the required capacity and venting extensions. The vessel itself should have approved steel or concrete supports. It should meet the 250 psi (1.72 MPa) working pressure and ASME code requirements and must be well grounded. The storage tank should have a pressure gauge, dier- mometer and liquid level gauge. Appropriate shut-off valves, emergency shut-off valves, back-flow check valves and excess flow valves should be used in conjunction with die liquid inlet, liquid oudet and vapor line. The tank should be painted in a white or pastel color and marked or placarded as to die contents. Pipelines should be laid out to allow for expansion and contraction of die metal and for expansion of liquid contents to prevent rupture between shut-off points. The latter is handled by hydrostatic relief valves in each section. All pipes should be painted and placarded as to contents and direction of flow. Unloading compressors or pumps should be mounted on a concrete base and kept fairly remote from tanks or other pumps, since seals have been known to leak, dien fail and cause ignition, producing fire plumes up to an estimated 60 feet (18.3 m) high. In large installations, these pumps have been collected into a pump house fitted widi gas detection equipment. All electrical equipment must comply with the National Electrical Code, Class I, Group D and be grounded. The unloading of grounded tanktrucks and tankcars is described in die National Fire Protection Association (NFPA) Pamphlet No. 58 and in odier literature. Startup and shut-down procedures for die entire system should be followed closely, preferably by check-list.
Aerosol Flammability 237 An uncontrolled fire in a tank farm, leading to the overheating of propellent tanks beyond the capability of pressure relief valves to drain off the excess pressure development, will cause eventual tank rupture and a truly awesome burning liquid expanding vapor explosion sometimes called a BLEVE. A large propellent tank might produce a blast-associated fireball up to 500 feet (150 m) in diameter, with upward drafts of up to 400 mph (590 ft/s, or 180 m/s). Steel and aluminum metals within the fireball are known to melt, be carried aloft, and then come down as a red hot rain. Buildings within a quarter mile (402 m) may be set afire from the radiation. Exposed persons some distance away may get mild "sunburns", severe "sunburns", burns, or worse, depending upon proximity. Tests carried out in England (at the School of Artillery, Larkhill, by Expamet Blevex Ltd.) in April 1979 proved that heavily insulated propellent tanks could survive a one hour heating from a kerosene fire as long and wide as the tank above it. The insulation was composed of about a 2 " (50 mm) air space, then 4 " (100 mm) of coated, expanded aluminum foil (15 layers, supported on Hi-Rib struts off the tank), a second 2 " (50 mm) of coated, expanded aluminum foil (15 layers, supported on Hi-Rib struts off the tank), a second 2 " (55 mm) air space, and then the whole encased in sheet metal. At least one major U.S.A. filler reviewed this option for tank protection and decided against it, due to cost and other reasons. Instead, the firm protected their many propellent tanks with a monitor gun (or "water cannon'') fire suppression system. Several cannons are mounted at widely separated points, such as roof edges or towers, near the tank farm. They are activated by temperature rate-of-rise detectors located throughout the tank installation. Supplied by either city water or private reservoirs, each water cannon can spray more than 600 g/m (2,300 liters/m) into the tank farm. The Gassing Room Installations for the gassing of hydrocarbon propellents into aerosol containers come in a diversity of designs, sizes, levels of relative safety and costs. A preferred system includes a gashouse physically separated from the main plant buildings by at least five feet (1.5 m). A number of fires and explosions have been caused by placement of gassing enclosures within plant buildings; however, in some cases this alternate is unavoidable. The gas house should be constructed with three rather substantial walls, preferably of concrete, plus a fourth wall that contains large "blow-out" panels. Since a hydrocarbon gas/air explosion can theoretically generate up to about 120 psig (827 kPa) — except that any gashouse would rupture first — it is necessary to protect operators from dangerous pressure build-ups by providing light-weight panels, sheer-bolted to wall frames so that they can blow outward at internal pressures of about 0.08 to 0.13 psig (0.55 to 0.86 kPa). The panels also serve to protect the gashouse from serious structual damage. Ventilation is the key to explosion prevention under normal operating circumstances, but its limitations must be clearly understood. For a typical gashouse with an air volume of 2,000 cu. ft. (56,600 liters) as little as 1.25 gallons (2.7 kg) of isobutane can bring the entire area to the lower explosive limit (LEL). Much less is needed to reach the LEL or beyond in specific areas, such as near the gassing machines. Considering that high-speed gassing operations often require as much as 15 g/m (56.8 liters/m) of liquefied propellent gas, it is easy to show that a serious rupture in an unprotected gas inlet line could bring the gashouse to a potentially explosive condition in a matter of a few seconds. The usual ventilation system changes the air in a gashouse once every minute, which would not have any significant ameliorating effect on the consequences of a serious rupture in an unprotected gas line. If the hydrocarbon sensing device detects a rise to 20% of the LEL value (about 0.4v% gas) an alarm is normally triggered and an interlock system causes the ventilation rate to be tripled — to an air change every 20 seconds. Finally, when the hydrocarbon detector system senses a rise to 40% of the LEL value, or about 0.8v% gas, a different alarm is sounded, the gasser is shut down automatically and the hydrocarbon inlet line is automatically closed by a solenoid-operated valve. In any event an inlet line would be protected by one or two excess flow valves, so that, even if a serious rupture occurred, the flow increase would act to shut off the gas supply. In the course of operations, various propellent leaks take place at the U-t-C or T-t-V gassers. The propellent liquestatic pressure in these machines and the inlet lines ranges from 550 to 800 psig (3.80 to 5.52 MPa). If certain metal components in the heads fracture, or if a pulsing flexible hose ruptures, the leakage rate can be intense. For safety purposes the closest excess flow valve should be located quite near the machine, without any accumulators, large diameter pipes or other high
238 The Aerosol Handbook capacity line components in between. This will act to minimize gas entry into the room as a result of the sudden leak. Various sensing devices are available to detect the build up of propellent vapors in the gassing enclosure. The most foolproof type draws the vapor/air mixture from 3/i6" (4.7 mm) copper tubing terminals placed in two or three strategic locations, passing the mixture across a continuous infra-red sensor that determines absorption at a specific waveband where the hydrocarbon gases are relatively opaque. The degree of absorption indicates the concentration of propellent in the mixture. If concentrations beyond the 20% LEL level are encountered, an interlock system acts to increase ventilation, sound an alarm and perhaps light up warning annunciator signals elsewhere in the plant. At 40% LEL levels the equipment is shut down and the gas supply closes automatically, as mentioned earlier. Some set-ups perform these functions at 25% LEL and 50% LEL, respectively. The equipment can be pre-set as desired. The system is made fail-safe so that in the event one or more of the ' 'sniffer'' intakes becomes inoperative — kinked tubing, vacuum pump failure, belt failure, etc. — the equipment will be shut down and the gas line shut off until the problem is remedied. One shortcoming of the equipment is that it takes a number of seconds for the gas/air mixture to travel through the copper or aluminum tube and finally reach the remotely located sensing unit. Infra-red systems are supplied by the Mine Safety Appliances Company (Pittsburgh, PA), Davis Instruments Division (North Charlottesvile, VA), Scott Aviation Company (Lancaster, NY) and the Bacharach Instrument Company (Pittsburgh, PA). A far less costly system is also available, which uses a thermal conductivity sensor at the site to pick up the presence of hydrocarbon vapors. Response time is thus almost instantaneous. The sensors can be inactivated by vapors or mists that can form a coating on the metal detection surfaces. Methylene chloride, silicones, varnishes and several other substances can act to breech the integrity or poison the sensors in this way. A few installations use only this type of system; some use both the infra-red and thermal systems together. Firms such as Bacharach and Mine Safety Appliances produce the thermal conductivity system. A lot of controversy still exists concerning other equipment that may be placed in the gashouses. It is not uncommon for them to also contain hi-pressure propellent booster pumps, check-weighers, button tippers, vacuum equipment and so forth. In one case, a gassing room contains a hot tank. Industry engineers appear to be about evenly divided on whether gashouses should only contain gassers, or also several pieces of other production-related equipment. In any event, all gas house electrical gear must be Class 1, Group D, Division 1 (explosion proof), and electrical equipment outside the gashouse, but within 30 feet (9.15 m) should be Division 2. It is very desirable to maintain the gassing room humidity at 70% RH or higher, generally by the use of steam jets. These jets can also be used to de-ice the gasser heads, provided a strictly anhydrous product is not being produced. The humidity acts to reduce the possibility of static sparking. A number of fires have occurred in gassing rooms. Most had an unexplained origin, but were probably initiated by triboelectric sparking at energy levels of 0.2 mj or above. Very costly copper-beryllium wrenches, hammers and other tools are often found in gas houses. The metal is soft, compared with hardened steel, so wear and damage can be a problem. The theory is that this alloy is only about 2 % as spark-prone as steel, when it strikes a steel surface, thus it is safer to use. Two arguments with this theory are that the LEL or flammable level should never be reached in the first place, and even if it were, mechanical sparks are not sufficiently energetic to ignite a hydrocarbon/air mixture. Nearly all gashouses have a system for extinguishing fires. They depend upon pressure, heat, or ultra-violet detection devices positioned on the ceiling or upper wall areas and react to fires by activating water deluge equipment (typically delivering 350 to 400 g/m (1,325 to 1,514 liters/m) or a ceiling-mounted cylinder or "egg" of Halon 1301 (CBrF3). The Halon type equipment is available from Walter Kidde & Company (Belleville, NJ), Fenwal, Inc. (Ashland, MA) and other firms. For the usual Halon 1301 fire suppression system, a pair of ultra-violet wide-range detectors are installed on the ceiling and a pair of back-up pressure-increase detectors are mounted on upper wall areas opposite each other. The UV system will pick up fire radiation in the 170 to 260 nanometer (nm) range, with peak sensitivity at 2150 nm. Detection and reaction time is about 5 milliseconds (ms). The detector unit sends an electrical signal to the solenoid striker between the Halon 1301 egg and spreader assembly, rupturing the
Aerosol Flammability 239 prescored bursting disc and letting the Halon fly out at injection speeds averaging about 200 ft/s (61 m/s). At the same time, the ventilation system is shut off, so that no Halon is wasted to the outside. The hydrocarbon/air flame front has a velocity of about 1.44 ft/s (0.44 m/s) at LEL. If a fireball of about 1 ft (305 mm) in diameter has been produced by the time detection is accomplished in the 6 ms before the Halon 1301 strikes it and total suppression is effected, the fireball will have grown to about 2.73 ft (0.83 m) in diameter. This scenario assumes a 15 ft (4.5 m) travel distance from spreader assembly to the core of the fire, and zero growth from the instant of contact. Actual results are more serious. In one example, the fireball was described as one quarter as large as the gassing room and momentarily engulfing the lone operator. In another case no dimension was given, but three persons in the room were engulfed. In both, the internal pressure rose by about 2.5 psi (17 kPa) and the people were somewhat dazed and had mild burns on exposed skin surfaces. Their cotton clothing did not burn. About 5 v% of Halon 1301 is necessary for explosion suppression. Halons have been discussed in the propellent chapter. In the case of Halon 1301 there are no human effects up to the 7 v% level in air, after 4 minutes of exposure. Above this, people were subject to lightheadedness and had a problem with mental concentration. It was non-lethal, even at very high levels. No cardiac arrhythmias were detected. The thermal decomposition products included hydrogen fluoride (HF) at 200 to 300 ppm, hydrogen bromide (HBr) at 40 to 50 ppm, plus bromine (Br2), carbonyl fluoride (COF2), carbonyl bromofluoride (COBrF) and carbonyl bromide (COBr2) at concentrations too low to measure and probably less than a few ppm. The major problem with Halon 1301 installations is economics. For example, a system in the Chicago area was set off by a person welding about 60 ft (18 m) away. About $5,000 of extinguishant was released into the gas house and the production line was down for the rest of the day, while arrangements were made to have the egg recharged and the system reset. These situations are now quite rare, since firms with this equipment have learned how to accommodate to its ideosyncrasies. Suppression systems are used principally to prevent or mimimize employee injuries. With blow-out panels and shut off systems, the protection of the gashouse and its equipment is a secondary function. Warehouse Storage of Aerosols Industry interest in the possible flammable hazard of stored aerosol products extends back to at least 1955, when large amounts of flammable or combustible substances were first introduced into formulations. Several isolated experiments were made where one to five 12-pack cases were placed in a bonfire. Two series of experiments were conducted in this manner near Jones' Beach, Long Island, NY, where photographs of rupturing cans were taken to help determine the optimum ethanol concentration in a hair spray. In one informal study, about 25,000 cans of a predominantly kerosene product were ignited, producing a fire averaging 50 ft (15 m) across, plus large amounts of dense black smoke. In one photograph, a flying can was clearly outlined at a height of about 170 ft (52 m). During the early 1960s a palletload of aerosol varnish was set afire by the Factory Mutual Engineering Corporation in their testing center at West Glocester, RI. A vigorous fire resulted which could not be controlled by the standard sprinkler system and had to be extinguished using fire hose. A film of the fire was taken, and the research results informally reported to the National Fire Protection Association (NFPA) and other organizations. The NFPA, which often sets recommended standards that are later enacted into national or local regulations, is an organization composed primarily of fire marshalls, insurance company engineers and industry in general. Among their diverse interests is the safe storage of flammable and combustible liquids, including aerosols. They have defined these liquids as follows: Class 1A Liquids having TCC flashpoints below 73°F (22.8°C) and having a boiling point below 100°F (37.8°C). Examples: isopentane, diethyl ether and aerosols defined as "Flammable" (or "Extremely Flammable") by the Federal Hazardous Substances Act of 1960. Class IB Liquids having TCC flashpoints below 73°F (22.8°C) and having a boiling point at or above 100°F (37.8°C). Examples: acetone, hexanes and ethanol. Class IC Liquids having TCC flashpoints at or above 73°F (22.8°C) and below 100°F (37.8°C). Examples: turpentine, n-butanol and n-nonane.
240 The Aerosol Handbook Class II Liquids having TCC flashpoints at or above 100°F (37.8°C) and below 140°F (60°C). Examples: many kerosenes, butylene glycol and Cellosolve Solvent. Class III Liquids with TCC flashpoints at or above 140°F (60°C) and below 200°F (93.3°C). Examples: less volatile kerosenes and pine oil. Class IIIA Liquids with TCC flashpoints at or above 200°F (93.3°C). Examples: propylene glycol, corn oil and mineral oil. Note: Class I liquids are considered as "Flammable" liquids and the others are considered "Combustible". The NFPA 30 recommendations stipulated storage restrictions for these liquids, which were most stringent for Class IA, and thus "Flammable" aerosols, as defined by the FHSA. Sanctions included maximum pile size in terms of gallonage and height, aisle placement and widths and the prohibition of basement storage for Class I liquids. At one time, Class IA liquids were recommended only for storage at heights up to 3 ft (0.91 m), but this was later raised to 5 ft (1.52 m). Even this was considered extremely oppressive and unwarranted for "Flammable" aerosols and the industry was greatly troubled by the recommendation, and often unable to comply with it for economic reasons. When the Occupational Safety and Health Administration (OSHA) was formed in 1970 they planned to engage in widespread standard-setting activities, and began adopting many voluntary consensus standards as regulations. The NFPA definitions were encoded into Chapter XVII, Sec. 1910.106 (13, 18 and 19) of the Code of Federal Regulations, and the recommended restrictions for storage were likewise adapted with no changes. The restrictions remained as OSHA regulations from about 1972 to 1978, at which time the agency, reacting to public and Congressional opinion, deleted about 1100 individual regulations, including all those that related to aerosols, with the exception of one that stipulated maximum gallonage per pile. Unfortunately though, during the 1970s several states and numerous local authorities adopted the NFPA/OSHA concepts into their own regulations. There is a great deal of inertia at these levels, and even now at least two states have regulations banning the stacking of "Flammable" aerosols over 3 ft (0.91 m) high. Fortunately, they are not enforcing them. In 1979 an attempt was made to get the NFPA to delete their definition of a "Flammable" aerosol as a Class IA liquid, or, failing in that, at least have such aerosols equated with Class IB liquids, so that stacking could be 10 ft (3.04 m) high in harmony with their recommendations. The attempt was initially unsuccessful and was not pursued in 1980 because of developments within the Factory Mutual Insurance group that impacted on this area. * The Factory Mutual Initiative* * The Factory Mutual Research and Engineering Corporation (Norwood, MA) is part of the Factory Mutual Insurance Group, which is jointly owned and operated by four major insurance firms: Allendale, Arkwright-Boston, Philadelphia Manufacturers and Protection Mutual. The company engages in loss analysis, risk analysis, training and other activities, making periodic recommendations to their associated commercial carriers regarding risk reduction and loss prevention. Factory Mutual (FM) has about 740 loss protection engineers who frequently accompany sales personnel on field trips, assessing the safety of warehouses and plants, and make recommendations for the reduction of risk to what may be termed an acceptable level. In some instances, retrofitment is necessary as continuing research uncovers new problems, or if the establishment is used for the storage of new, more hazardous goods than before. Once compliance with engineering standards is reached, the carriers will insure it or provide re-insurance, as the case may be. As a rule, the carriers provide their insureds with sufficient time to upgrade their warehouses, continuing their insurance coverage for periods up to two years or more if the firm promises to make the needed improvements. In most cases, the semi-annual or annual FM engineering "spec" of warehouses results in anywhere from one to ten recommendations for improvement. In many cases, the owners can respond in writing, stating that they feel they are applying safe storage conditions and *One interesting legal analysis suggests that the NFPA definition of a "Flammable" aerosol is tied to the FHSA definition in laws now administered by the CPSC. As such, it only relates to household products — not to pesticidal, food, drug or cosmetic aerosols. Consequently, at least 40% of all aerosol products would not be subject to the NFPA Class IA liquid definition, or regulations by various authorities based upon the NFPA liquid classifications. In any event, the NFPA Code 30 is scheduled for a total review in the near future, and it is hoped that the industry can insert some beneficial changes into the wording on aerosols at that time based on test data still being collected. **This section is written with some reluctance, since the complex situation is still developing and the end results may be quite different than what is viusalized at this time. No standards or recommendations are proposed or implied.
Aerosol Flammability 241 no actions are contemplated. This often ends the matter, unless serious deficiencies are involved. The carriers associated with FM are known as HPR (Highly Protected Risk) insurers. Their rates are very low, since the risk has been reduced to a practical minimum in the establishments they insure. IRI (Industrial Risk Insurers), Kemper, IRM (Improved Risk Mutual) and other carriers offer the same type of coverage, and there are also many other insurers that adjust their premiums on the basis of perceived risk level. These latter companies, however, usually have rates which are significantly more than that of HPR insurance. The FM carriers may form the largest property insurance unit in the world. Through Factory Mutual International they operate in a number of countries and are said to insure over 20,000 business establishments worldwide. Most are plants and warehouses, but some are large retail outlets as well. The FM research facilities are the most sophisticated available for large- scale warehouse fire testing. As a result, their technical recommendations are treated with respect. They are looked at both by recommending bodies (Underwriters Laboratories and NFPA) and standard-setting organizations (BOCA and UBC) as the acknowledged technical leader in the field of fire control. For example, the UBC is the United Building Code Organization, which operates in the thirteen western states. Within the UBC a committee of fire chiefs and persons with similar interests are now developing what is called the United Fire Code (UFC); a document that will affect the construction and fire protection requirements of commercial buildings for years to come. They are using the published FM loss prevention data in their decisionmaking activities. Regulatory bodies and other insurance carriers often accept or are at least influenced by the various FM recommendations. Consequently, although there may be a lag time of (say) six months to six years for these large organizations to develop or change their codes, the pronouncements made by FM have a very large long-term effect, influencing many other aspects of fire control, safety and risk assessment outside the company. FM's interest in aerosols was sharpened during 1978 and early 1979 when three warehouses had fires which caused over $250 million in damage. They were insured in part by the FM carrier companies. The investigations that followed showed that both warehouse structures and the goods they contained had changed greatly during the 1970s, to the extent that the standard protection systems could no longer effectively cope with the new hazards. Many warehouses had grown taller; some were now over 100 ft (30.5 m) in height, with racks from floor to ceiling and often supporting the roof. Pallets were moved in and out by computer-controlled stacker cranes or automatic track and lift operations. Any fires that started in these high- rise structures could readily grow to heights of 60 to 80 ft (18.3 to 24.4 m) within several minutes, prior to activating the ceiling sprinkler system. By that time control might be extremely difficult or impossible. Very large warehouses had also come into vogue. One section of the huge Ford warehouse that burned during 1978 in Merkenich, West Germany had an area of over 18 acres (7.2 ha or 7.6 million ft2). Numerous warehouses in excess of a million ft2 (0.95 ha) are now operated in the U.S.A. One of these burned in the Edison, NJ area during 1978 and aerosols are alleged to have been involved in spreading the initial fire. The other factor was that the nature of the stored goods had changed. The most significant change was the greatly increased use of plastics, replacing metal, wood, paper and other traditional materials in both products and packaging. Probably the most flammable form of plastic is polystyrene foam and similar foam structures, used for paper cups, meat trays, mattresses, cushion-packaging and so forth. Finally, it was recognized that some aerosol products now had higher contents of flammable ingredients and might be more hazardous. In 1979 FM engineers designed a series of fire tests to reevaluate their guidelines for protecting warehouses. The program was divided into two sections; one was related to rack storage of ordinary and mixed combustibles and plastics. The other involved aerosols. The aerosol program, funded at about $200,000, consisted primarily of the evaluation of FM's three classes of products: water-based, alcohol-based and liquid petroleum based. Large numbers of aerosol cans were purchased from a local filler. They were of the 211 x 604 (65 x 158 mm) size and had either 9 or 10 Av. oz (255 or 284 g) fills. The water-based prototype product consisted of 65% water and 35% of hydrocarbon propellent A-70, the alcohol-based type contained 65% isopropanol and 35% hydrocarbon, and the liquid petroleum based formula was composed of 65% toluene and 35% hydrocarbon. These formulations were supposed to represent the full range of aerosol formulations and packaging variations.
242 The Aerosol Handbook The results of the FM tests have been published in Fire Record, (pg 10, Sept/Oct-1980) and other journals. The water-based formula was tested first. A single palletload, consisting of 72 12-pack cases of aerosols, was ignited at the bottom using a cotton ball saturated with 4 oz (113.4 g) of n-heptane. As the corrugate fire grew, some cans ruptured, but the 0.3 gpm (12.3 liter/m) sprinkler system controlled it easily. Other storage arrays were tested with the same results. The test team concluded that these products could be protected effectively by sprinkler systems recommended for ordinary combustibles. The fires were related to the Class A types, generated by paper and cardboard commodities. These tests were conducted at the FM Research Center at West Glocester, RI, where two test pads are available and can be set up to duplicate most warehouse configurations. The sprinkler system has nearly 1000 sprinkler positions. Various horizontal spacings, sprinkler head sizes, water pressures and other variables can be handled. The ceiling system in the Figure 11. Warehouse Fire Involving Aerosols Photo of early stage of warehouse fire, involving aerosols formulated with 65% isopropanol and 35% A-70. Ceiling sprinklers rated at 0.3 gpm (12.3 liter/m/m2) with 286°F (141°C) linkages were inadequate for control. A partly dispersed fireball accounts for the enlargement of the upper reaches of the fire. Only a small amount of smoke has been formed. • * main test area is 30 ft (9.14 m) above the floor, but platforms can be erected to reduce this distance if desired. The usual sprinkler system for a general purpose warehouse consists of a "Christmas tree" or more modern grid type piping arrangement, starting with 6 to 8 " (152 to 203 mm) mains that connect to the water tower, reservoir or city water supply. As the system spreads across the warehouse ceiling area, the pipe size gets progressively smaller, down to a 1" (25 mm) end- pipe size (as a rule) to accommodate the usual J4 " (13 mm) threaded connection to the 30 gpm (114 liter/m) individual sprinkler heads. The heads may be fitted with fusible lead-alloy activators that melt at 286° or 160°F (141° or 71°C). Fusible linkages are available at other temperature ratings, but are much less popular. The 286°F (141°C) heads are used most commonly for ceiling sprinkler systems, since for most fires they were found to provide an optimum response: actuating fairly promptly, and yet not melting the linkage so readily that the system is compromised by the operation of an excessive number of heads, some of them not over the actual fire. The 160°F (71°C) heads have been preferred for in- rack storage protection, where they are often back- mounted on each storage tier at 8 ft (2.44 m) intervals, as an extension of the basic ceiling system. Recent data suggests that for use over aerosol products, these low- melting heads may be better than the 286°F (141°C) type for ceiling sprinklers. The ceiling systems generally contain sprinkler heads at 10 ft (3.05 m) intervals, so that every head controls an area of 100 ft2 (9.29mz). Thus, if the head is rated to spray 30 gpm (114 liter/m) at standard water pressure (generally 25 to 30 psig or 172 to 207 kPa), the sprinkler density is rated as 0.3 g/m/ftz (12.3 liter/m/m2). In abbreviated form, the density is simply mentioned as a number, or as a number identified as "gpm" to indicate that the English system is being used. The FM test team then began the evaluation of alcohol-based aerosols, thought to represent a medium- range hazard. They set up a 20 ft (6.1 m) high row of racks, two pallets deep, four pallets high and six pallets wide. In the center they placed eight pallets of actual aerosols (four high and two wide). The rest of the pallets contained corrugate boxes with metal liners. Also, on the other side of an 8 ft (2.44 m) aisle they placed a target rack filled with more dummy cases. The only fire control in this test was a 0.3 gpm (12.3 liter/m/mz) ceiling sprinkler system.
Aerosol Flammability 243 The FM engineers ignited the aerosols at floor level, using the standard cotton/n-heptane wad. In about 1:50 minutes the fire had reached a height of about 2Q ft (6.1 m) and cans started to rupture. Some rocket propulsion also took place. When the individual cans exploded under a pressure of about 225 psig (1.55 MPa) and equivalent equilibrium temperature of about 160°F (71.1°C), the 35% of hydrocarbon A-70 blend propelled the flaming contents outward in all directions, resulting in a fireball of approximately 9 ft (2.74 m) in diameter, lasting for about a second. The characteristics of the fire in its early stages is shown in Figure 11. The fire got out of control very quickly and had to be extinguished by using a combination of greatly increased water pressure in the sprinkler system (about 90 psig or 621 kPa) and manually operated fire hoses. The next test was a repetition of the previous one, except that in-rack sprinklers were used in addition to the ceiling system. In this case the fire was controlled, although some cans did rupture. The flames did not spread across the 8 ft (2.44 m) aisle. When a fire is listed as "controlled", this does not mean that it has been extinguished; only that it has been reduced to proportions that are not expected to enlarge as long as sprinkling continues. For example, fires deep within the framework of oak pallets cannot be reached by sprinkler water and will continue to burn until extinguished by fire hoses operated manually. The third test was similar to the second, but with the number of palletloads of product escalated from 8 (1 x 2 x 4 high) to 24 (2 x 3 x 4 high). The fire was more intense than before, but was eventually controlled by the combination of ceiling and in-rack sprinklers. The fourth test was the only one involving floor storage. Twelve pallets were assembled into a 3 x 4 x 1 high array, about 12 " (305 mm) apart. A 0.3 gpm (12.3 liter/m/m2) ceiling system was used. After ignition between the palletloads, many cans ruptured and the fire was intense, but the sprinklers were able to control the fire, with less than half the cans becoming involved. The results left open the question of what would happen in the event of storage of two and three palletloads high, if ignition occurred. The final test for the alcohol-based product series involved a small in-rack storage array of pallets, 2x2x2 high. Only ceiling sprinklers were provided. An ignition at the center caused a rapid fire development which grew out of control. The test had to be aborted. The conclusions reached by the FM engineers at the end of this test series were that aerosols with alcohol- based contents can be protected with ceiling sprinklers if they are stored in solid piles about one palletload high, but if stored in racks, both ceiling and in-rack sprinkling must be used if the fire is to be controlled. The last product to be tested was the toluene/hydrocarbon prototype. This was expected to give the sprinkling system its most severe test, since the BTU (kcal/g) content was about 20% higher than the isopropanol/hydrocarbon blend. Furthermore, the toluene is also water-insoluble and tends to create floating, burning layers upon water. Smoke generation was also expected to be a problem. In the first sequence, the FM engineers set up a rack storage of eight pallets with a 2 x 2 x 2 high configuration. A target row of dummy cases was set up across an 8 ft (2.44 m) aisle. Both ceiling and in-rack sprinkler systems were used, with the heads rated at 0.3 gpm (12.3 liters/m/m2). The fire spread quickly, generating fireballs and spread across the aisle quite easily. It was soon aborted because the sprinklers could not effect control. The second test was limited-height solid floor pile study, involving an array 3x4x1 high. Ceiling sprinklers rated at 0.3 gpm (12.3 liters/m/m2). Shortly after ignition, flames engulfed the entire pile and the test had to be aborted. In a subsequent study only a single palletload was ignited. Within four or five minutes, even this small amount of storage got completely out of control and the test had to be aborted. Nearly every can had ruptured and all flammable contents had been consumed when the fire was finally extinguished. These three tests convinced the FM engineers that standard 0.3 gpm (12.3 liters/m/m2) sprinkler systems were inadequate for this type of aerosol formulation. In the next three tests with the toluene/A-70 prototype product, the FM engineers used special sprinkler heads with larger orifices rated at 0.6 gpm (24.6 liter/m/m2). These heads had orifices of 17/32" (13.5 mm) diameter instead of the V2 " (12.7 mm) diameter used previously on the 0.3 gpm (12.3 liter/m/m2) heads. Despite the cross-sectional enlargement of only 13%, these new heads could deliver twice as much water to the fire with the same water pressure (30 psig or 207 KPa). In the first test a rack storage was set up using a 2x2x2 high pallet configuration, along with a target row of palletloads across an 8 ft (2.44 m) aisle. Cans
244 The Aerosol Handbook began to rupture about 2 Vi minutes after ignition, but the combination of high-density ceiling sprinkler heads and standard density in-rack sprinklers controlled the fire. A floor-standing array 3x4x1 high was then set up and ignited. Although there were fireballs and heavy smoke, the 0.6 gpm (24.6 liter/m/m2) sprinklers controlled the conflagration. In a final, larger test an array of 24 palletloads (2x3x4 high) was placed in racks, with a target row of 1 x 2 x high aerosol palletloads directly across an 8 ft (2.44 m) aisle. Fireballs and dense black smoke were produced a little over two minutes after ignition, and about a minute later the fourth (top) tier of the target row caught fire. Despite the intensity of the fire, the high-density ceiling sprinklers and regular 0.3 gpm (12.3 liters/m/m2) in-rack sprinklers controlled the blaze. The results of the many FM tests are summarized in Table XV. They showed that aerosol products can be stored safely in warehouses, provided sufficient sprinkler water is provided. For water-based items the standard 0.3 gpm (12.3 liter/m/m2) ceiling sprinklers were found sufficient under all storage conditions. For alcohol-based formulas, the standard ceiling sprinkler system was found to control one-high floor storages, and in rack storage, standard in-rack sprinklers must also be used. Finally, for liquid petroleum distillate types, the FM tests indicated a need for high-density, 0.6 gpm (24.6 liter/m/m2) ceiling sprinklers to control Table one-high floor storages, while for in-rack storage, both these and standard 0.3 gpm (12.3 liter/m/m2) rack sprinklers were needed. There were also concerns about smoke generation and flying, flaming cans in the case of the liquid petroleum distillate formulas. It was thought that the flying cans might ignite satellite fires, possibly putting an intolerable strain upon the overall sprinkling system. The aerosol industry was made aware of the FM test results at about the beginning of 1980. CSMA immediately assumed a lead role for response, forming an Aerosol Storage Task Force and later a Protocol Development Task Group to design and execute further tests. The industry disagreed with the FM position that their aerosol testing was about 95% complete. Several experts considered that it was more like 35% complete and that more testing was necessary to provide sufficient cost effective alternatives, especially for bulk pallet storage, as opposed to in-rack storage. It would be premature to try to get thousands of warehouses — plants, distribution centers, supermarket storage areas and so forth — to upgrade their fire protection facilities for the storage of flammable aerosols. Typical questions that circulated throughout the industry at the time can be illustrated as follows: a. Which of the three FM categories (water-based, alcohol-based or liquid petroleum based) fits my products? For example, antiperspirants, hydroal- coholic products, emulsion types and products XV Summary of FM\ Test Results of 1979/80 on Aerosol Prototypes Class Aerosol Concentrate Pallet Array Stacking Floor Rack Sprinkler Size Ceiling Rack Result Water-based Water-based Water-based Alcohol-based Alcohol-based Alcohol-based Alcohol-based Alcohol-based Liq. P.D.-based Liq. P.D.-based Liq. P.D.-based Liq. P.D.-based Liq. P.D.-based Liq. P.D.-based 65% Water 65% Water 65% Water 65% Isopropanol 65% Isopropanol 65% Isopropanol 65% Isopropanol 65% Isopropanol 65% Toluene 65% Toluene 65% Toluene 65% Toluene 65% Toluene. 65% Toluene lxlxl 2 x2 x2 2 x2 x2 1 x2 x4 1 x2 x4 2x3x4 3x4x1 2x2x2 1 x2x4 3x4x1 1 xl xl 1 x2x4 3x4x1 2 x3 x4 X X X X X X X X X X X X X X 0.3* 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.6** 0.6 0.6 0.3 — 0.3 0.3 0.3 • 0.3 0.3 Controlled Controlled Controlled Not Controlled Controlled Controlled Controlled Not Controlled Not Controlled Not Controlled Not Controlled Controlled Controlled Controlled *0.3 gpm (12.3 liter/m/m2) standard (General Purpose Warehouse) sprinkler heads, with Vi " (12.7 mm) orifice and 286°F (141°C) linkage. **0.6 gpm (24.6 liter/m/m2) high-challenge sprinkler heads, with 1kt" (13.5 mm) orifice and 286°F (141°C) linkage. fFM = Factory Mutual Research & Engineering Corp.
Aerosol Flammability 245 with very high levels of non-flammable chlorocar- bons were impossible to categorize. b. Are all liquid petroleum based products equivalently dangerous? For example, it was recognized that the 65% toluene prototype caused the activation of 36 0.3 gpm (12.3 liter/m/m2) sprinkler heads when a single pallet was ignited, but other tests, involving paint products with 70 % of a toluene-based concentrate, only opened 4 sprinkler heads of identical design and capacity. c. Why was so little emphasis given to floor standing palletloads in the FM program (only five tests) and why was no testing done in the case of floor standing aerosols over one pallet (5 ft or 1.52 m) high? For example, possibly 90% of warehoused aerosols are stored on the floor in multi-pallet heights not tested by FM. d. Could improvements in storage design reduce flammability hazard? For example, the floor standing FM tests were conducted with sprinkler heads about 25 ft (7.62 m) above the stock, which gave the fires a chance to develop more fully before the system was actuated. Tests at Southwestern Research Institute, Texas have indicated an optimum distance of from 3 to 8 ft (0.91 to 2.44 m). e. Could improvements in package design reduce flammability hazard? For example, the use of flame retardant cases and/or dividers, highly water absorbant cases and/or liners, or specially designed cases to enhance content wettability. f. If the four insurance carriers associated with FM insist upon cost-intensive retrofitment of warehouses containing flammable aerosols as a condition for continuing HPR coverage, is there any merit in transferring to non-HPR forms of insurance coverage? Additional testing was necessary in order to answer these and a myriad of other serious questions. About $250,000 was subsequently raised by the CSMA, in terms of collections and pledges from firms in both the U.S.A. and abroad, to fund a program of further testing. Protocols were developed by the industry and then technically reviewed with FM engineers before each phase of the testing was done at the FM Research Center at West Glocester, RI. At the time of this writing (June 1, 1982) CSMA is beginning to seek further funds to continue the program. During July, 1981, after a year or so of review and approvals, FM published their "Loss Prevention Data 7-29S" titled "Storage of Aerosol Products". This ten- page document had been developed prior to the initiation of the first CSMA tests (Nov. 24, 1980), and thus took no cognizance of CSMA's test results. Many of the statements surprised the industry, particularly since the conclusions and recommendations were all based upon prototype products quite different than the real ones they were designed to represent. The aerosol industry would have preferred that FM refrain from issuing any datasheet until the results of CSMA's program could be developed and evaluated. In their datasheet, FM stated that 10 to 80% of the contents of an aerosol is the propellent, such as isobutane and propane. They felt that their testing suggested that the propellent adds little to the overall hazard (at least up to 35%), so that the flammability of the base product is the major consideration. If the product (concentrate) contains more than 80% water it should be classified as a water-based product and treated the same as ordinary combustible goods for warehousing purposes; e.g. Class III commodities. Alcohol-base products were not otherwise identified. The FM recommendation was that they be stored without restraints anywhere in the warehouse, but floor storage should be limited to one palletload or 5 ft (1.5 m) high. Ceiling sprinklers should be designed to provide 0.30 gpm (12 liters/m/m2) over 2,500 ft2 (230 m2) using 286°F (141°C) heads. Pile sizes should be limited to a total of 25 palletloads and separated by a minimum of 5 ft (1.5 m) from other storage piles. For in-rack storage, in addition to the ceiling system just mentioned, rack sprinklers should be installed every 8 ft (2.44 m) using 165°F (73.9°C) heads. One line for every tier except the top tier. Hose stream demand was suggested as 750 gpm (2.8 m2/m), if cut-off rooms are not used. From these recommendations the total water requirement can be calculated. In the case of a floor storage area of 2,500 ft2 (230 m2) the maximum ceiling sprinkler demand would be 750 gpm. Adding this to the 750 gpm demand (for three 2.50 " (64 mm) fire hoses) the total becomes 1,500 gpm (5.6 m2/m). this amount of water can usually be supplied by a reliable city water main system. If not, either a water tower or reservoir would be required. The capacity of these water storages would have to be at least 180,000 gallons (672 m2) — enough to supply the maximum for at least two hours.
246 The Aerosol Handbook It should be emphasized that this "maximum scenario" assumes that every sprinkler in the 2,500 ft2 (230 m2) minimum controlled area will be activated. This would amount to 25 sprinklers. To put this in perspective, a fire that is well controlled may actuate 4 sprinklers or less. Those that set off over about 12 sprinklers are regarded as serious. The FM datasheet then gave recommendations for petroleum-liquid based aerosols, where their concerns were greatest. Because of rocketing cans and potential exposure of other commodities, they recommended that these aerosols be stored in a one hour fire-resistant cutoff area. (A wall with this level of fire resistance can be constructed with a surface of Yi" (12.3 mm) thick plaster-board or sheetrock.) Floor storage should be limited to one palletload or 5 ft (1.5 m) high. Ceiling sprinklers should provide a density of 0.60 gpm (24 liters/m/m2) over 2,500 ft2 (230 m2) with 17/32" (14 mm) orifice 286°F (141°C) rated heads. For in-rack storage, in addition to the ceiling sprinkler system, rack sprinklers should be installed every 8 ft (2.44 m) using 165°F (73.9°C) heads rated at 0.30 gpm (12 liters/m/m2). One sprinkler line should be used for each tier except the top tier. For this overall method of protection, storage heights are limited to 20 ft (6.1 m), but another sprinkler configuration, not listed here, is available for still taller constructions. Finally, if the distance between the top of the storage and ceiling sprinklers exceeds 15 ft (4.57 m) a barrier should be installed, over the top tier of storage and in-rack sprinklers provided beneath. Considering the suggested hose stream demand of 750 gpm (2.8 m2/m) and the maximum ceiling sprinkler demand over the minimum 2,500 ft2 (230 m2) floor storage area, the total water requirment for floor storage can be calculated as 2,250 gpm (8.4 m2/m). This is beyond the average capacity of many city water main systems. The alternate would be to use either a water tower or reservoir. The capacity of these storage systems would have to be at least 270,000 gallons (1009 m2), or enough to supply the maximum requirement for at least two hours. With cut-off rooms of less than 6,000 ft2 (560 m2), reductions of the fire hose demand are permitted. In the case of rack storage areas used for petroleum- liquid based aerosols, the total water requirement would be still higher, depending upon the extra demand for the rack sprinkler heads, with the exact amount subject to in-rack storage provided. If a reservoir is contemplated, a suitable pumping system will have to be provided. The capacity will depend on the type and quantity of aerosols in storage under maximum foreseeable conditions. Some city water systems get down to pressures as low as about 5 psig (34 kPa) at times of peak demand: those below 30 psig (207 kPa) will need pressure upgrading by means of a pumping station. The average water tower will provide the 30 psig (207 kPa) minimum pressure requirement listed in the FM datasheet, assuming the vertical head or distance between the bottom of the tank and the 6 to 8 highest (and most remote) sprinkler heads is sufficient. Considering a modern grid system, where the pressure is essentially flat, a head of 69.2 ft (21.1 m) is then needed. Literature available for some newer sprinkler heads suggest that density, water pressure and head design are all important for fire control. Pressures in the area of 50 psig (345 kPa) appear to be minimum for some of these sprinklers, giving a combination of small water drops for evaporative cooling near the ceiling (to avoid setting off more heads than really needed), and larger water drops to go into the fire plume and into the seat of the fire to fight it directly. Any need for these higher pressures must be considered against the backdrop of limitations that apply to existing water supply and sprinkler systems. The industry hoped to achieve a reduction of the stated FM 2,500 ft2 (230 m2) minimum control area, based upon the good results of recent tests. (Note: in 1982 the Viking head was informally rated for 1,500 ft2 (138 m2) minimum. City water mains will then probably be able to continue to supply the anticipated needs of most warehouses and distribution centers. Any firms contemplating adjustments to their fire control systems should consider what has been reported here only as a general guide, necessarily incomplete in the interest of brevity and confidentiality, and subject to revisions as the art of aerosol fire-fighting develops further. Competent fire engineers should always be consulted, as well as local fire codes. Product Reformulation A great deal of confusion exists as to how to fit existing aerosol formulations into the three categories (water-based, alcohol-based and liquid-petroleum based) in the FM recommendations. It is probable, however, that about one-third of U.S.A. aerosol formulas can be fitted into each class as they apparently
Aerosol Flammability 247 were meant to be defined. Many products must be considered borderline. For example, many furniture polishes contain about 20% petroleum distillate in the overall formula, and this would mean that the concentrate portion would have to contain less than 80% water. They would then be classified as petroleum- liquid based products and made subject to the fire control requirements just mentioned, according to the FM datasheet. On the other hand, actual test results have demonstrated that these formulas are no more hazardous than products containing more water, and should be included in the water-based category. Reformulation might be considered as an option, but it is hard to justify the derogation of a fine product in order to force it into an artificial storage category. On the other hand, many aerosol products can be reformulated with the addition of water, or more water, as a goal. In some cases this may result in a change of category. Paint products can now be prepared with about 35 % water, and some of these commercial formulations use dimethyl ether instead of the usual hydrocarbon A-70 blend. (Dimethyl ether has 69% of the BTU value of the hydrocarbons.) In any event, it is very doubtful if paints can ever be formulated with sufficient water to fit into the FM water-based category. Ultimately, it may be practical to have certain formulations specifically tested by FM to determine if they are sufficiently safe to be exempted from their liquid petroleum based class and placed in a less hazardous one. On a more positive note, such products as anhydrous bug killers, mothproofers and engine cleaners can be reformulated using sufficient water (80% in the concentrate) to be fitted into the FM water-based category. The addition of water to ethanol-based products has been looked at. For example, hair sprays are on the market with up to 9% water and the technology exists to raise this amount to at least 30%, while still maintaining a single-phase liquid. For some formulas, however, there are questions of wetness and (in general) consumer acceptance. In the 1960s hair sprays with 30 to 35% water were marketed, but they were two-phase liquids and never did well. Such brandnamed hair sprays as Cindy and French Touch were discontinued by about 1965. Personal deodorant sprays can be formulated with 5 to 8% of water before phase separation occurs, but they are then perceived as wetter than before, so this approach is generally contraindicated. Disinfectant/deodorant sprays usually contain modest amounts of water, which has been shown to make them more effective against many microorganisms. In no case has it been possible to reformulate a so-called alcohol-base product into a product fitting the FM definition of a water-based formula. As merely one way of looking at the way flammable hazard increases with flammable content, we can suggest the approach illustrated in Figure 12. About 70% of all warehouse fires are caused by human error. Some 14% are caused by incendiarism. The arsonist quite often sets two or three separate fires, putting a severe and often intolerable strain on the sprinkler system. Equipment failure, lightning bolts and other random causes account for a minority of warehouse fires. Static sparking of damaged aerosol cans was the probable cause of a $515,000 loss in California. A spark from the electric motor of a fork lift truck ignited an area containing reject and often leaking butane lighter fuel containers in a warehouse in Stoke-on-Trent, Staffordshire, England. The building contained 2.5 million aerosols, including air fresheners, furniture polish and other items. The loss was about $3.5 million and occured in Feb., 1980. A third fire was caused by stacking paint cans too close to a radiator, so that the exces- s w «s rim Bo HE Kg «* © s fa •d y > S ^ y^ Petroleum-liquid / base formulation* / /Alcohol-based / / formulations 25 50 75 PETROLEUM-LIQUID BASE OR ALCOHOL-BASE (%> 25 METAL SALT OR OTHER TOTALLY NONFLAMMABLE COMPONENTS (%) Figure 12. Graph Charting Flammable Storage Hazard Increase of flammable storage hazard with flammable content of aerosol concentrates (As estimated by the author). Assumptions: that the hydrocarbon propellent, if used, is 35% or less; and that chlorocarbon ingredients are absent.
248 The Aerosol Handbook sive heat ruptured them, after which they ignited. And a fourth was started by flames or sparks from the exhaust of a lift truck, parked near palletloads of hair spray, so that the corrugate ignited. Warehouses associated with manufacturing facilities are probably more susceptible to fire than buildings used solely for storage purposes. In England, two plants burned as a result of the release of hydrocarbon gas in one case and the spillage of a drum of flammable solvent in another. Details on these and other major fires have been published in the Fire Prevention Journal, Dec, 1980, in a U.K. Insurance Technical Bureau publication titled "Aerosols — the hazards of manufacture, storage and use in the United Kingdom, (1980)" and in other periodicals. A key to success in controlling aerosol fires is quick sprinkler response. The initial test series conducted by FM indicated response times of not less than about 2 minutes after ignition, and often shortly following rupture of the first aerosol cans of alcohol-based and liquid petroleum based products. Depending upon the aerosol contents, distance to the sprinklers and similar aspects, 10 minutes may elapse between ignition and sprinkler actuation. Modest reductions in these latency periods may be effected by the use of 160°F (71°C) bismuth- alloy linkage heads, by differently designed heads and so forth. An improvement in response time may be provided by specific detection units. They can range from highly simplistic smoke or heat sensor units with audible alarm, to a highly sophisticated system of electrically connected combinations of smoke, fixed temperature and rate-of-rise (in temperature) detector units. In the ideal system, these sentinel stations will cause an audible alarm to sound at one or more fire alarm control panels, where quick reference to the specifically illuminated zone of annunciation on the panel will show the plant or warehouse area in trouble. As a guard against malfunction of a particular sensor, many systems require the actuation of two units for a full-alert response mode, often including the automatic operation of an alarm in a nearby fire station. The best heat detectors are the combination rate-of-rise and fixed temperature type. The best smoke detectors are of the solid-state photoelectric type, operating on the light- scattering photodiode principle. These detectors are typically factory set to detect smoke at a nominal 15% light obscuration per foot, regardless of the rate of combustion, the distance between the detector and the fire source, the combustible material, the temperature or velocity of the smoke and whether the fire is in a confined or open area. They are designed also to ignore invisible airborne particles or smoke densities below the factory set point. Combinations of these detector units are normally ceiling mounted on a 15 x 15 ft (4.57 x 4.57 m) grid. Individual zones comprise anywhere from 3 to 40 detectors and are usually identifiable areas within the plant or warehouse, such as the staging area, or the north warehouse addition. In one example, a 345,000 ft2 (32,100 m2) plant required 18 zones. Smoke detectors are generally preferred for areas where storage density is high and people density is low; temperature detection units are usually suggested for the reverse, such as laboratories, maintenance shops and cafeterias. If desired, the automatic actuation of sprinklers can be effected in hazardous areas, using sprinkler supervisory devices. In 1982 the installation of a complete smoke/tempera- ture/rate-of-rise detection system with 120V-AC con- duited power, control units and so forth cost about $14,000 for 100,000 ft2 (27,870 m2) filled stock warehouse. Such systems are installed to greatly reduce detection time in case of fire. Detection is often accomplished in less than a minute after a reasonably large-scale ignition. Although automatically calling the local fire department is sometimes the only response, most plants and warehouses place some reliance upon their own people to converge upon the fire and try to either contain it or extinguish it while it is still quite small — and has not yet had time to start rupturing aerosol cans. Many states have regulations concerning the organization, training and other aspects of a fire brigade. If such a formal response activity is contemplated, state and local regulations should be reviewed. Suppliers of these fire control systems include the Autocall Division of the Federal Signal Corporation (Shelby, OH), the B&A Division of George E. Miller, Inc. (Terre Haute, IN) and other firms. They will assist in designing custom engineered systems to match the individual needs of warehouses and filling plants. Warehouse Storage of Aerosols - International Concerns relating to the safe storage of flammable aerosols are not limited to fire prevention organizations in the U.S.A. Conflagrations involving multi-million unit aerosol storages have occurred recently in England, West Germany, Nigeria and South Africa. In
Aerosol Flammability 249 fact, the disaster in South Africa, which destroyed the facilities of Alupac (Pty.) Ltd., is reported to be the most serious aerosol plant fire in history, with several deaths and over a hundred persons hospitalized. The firm was South Africa's largest contract filler. The fire took place in Feb., 1982. For purposes of brevity, the warehouse storage situation in only one other country is reviewed here. In the U.K., there are several overlapping regulations, plus others in progress, that deal with aerosol storage. The general "Petroleum Regulations" define volatile petroleum mixtures as those containing ingredients directly derived from petroleum with a flash point below 73°F (22.8°C). To store more than 3.6 (U.S.A.) gallons (13.6 liters) of such materials requires that the premises carry a petroleum license. CFC aerosols do not pose a problem, but for kerosene-based products that are hydrocarbon propelled this restriction can be very real. Such products fall under the definition of "Highly Flammable'' in the Highly Flammable Liquids and Liquified Petroleum Gases regulations, which control the storage and labeling of aerosols containing more than 500 ml of product, where the contents include over 45 % or over 250 g of flammables — substances with a flash point equal or less than 212°F (100°C). In addition, the Health and Safety Executive (Committee) (HSE), under the Health and Safety at Work Act and the Sixth Amendment of the Substances Directive, is drawing up three sets of regulations covering the storage of hazardous commodities (including aerosols) at all places of work. The first is directed at flammable gas storage. The general proposals have been approved by the Advisory Committee on Dangerous Substances and a draft of the regulations could well be published for public comment during 1982. But, as yet, the contents are not known with any accuracy. There is some likelihood of a modest quantity exemption for aerosols, but not for enough to cover a typical supermarket situation. The second covers flammable liquids. Fortunately, it contains an exemption for most aerosol products. The third is more general, and would appear to divide aerosols into two or three classes of flammability, which would affect how they must be stored in a warehouse. If only good housekeeping principles are required, then there will be few problems; but if segregated storage, fire resistant structures or other restrictions are involved, then the regulations will be extremely serious for business at both the wholesale and retail levels and could badly damage the marketing of aerosols. At this point, it looks like segregated storage and similar sanctions may be proposed. The European industry has followed the FM activity as closely as possible. Their sprinkler heads and other aspects of the control system are different than the American standards and this has been of some concern. Because of the role of a fork lift truck in the reported initiation of the very large Permaflex warehouse fire, the British Aerosol Manufacturers Association (BAMA) is planning some studies of such factors as the crushing of a single can of highly flammable product in a warehouse under a variety of conditions. Across the world there seems to be a growing awareness of the flammability of hydrocarbon based and CO2 based anhydrous aerosol products. What it portends in terms of warehouse requirements is difficult to assess at this time, but it seems logical that improvements in fire control systems and structures will be required, first by several insurance firms and later by various authorities. Safe Disposal of Aerosol Containers During the late 1970s, and particularly starting about 1980 both safety and regulatory concerns caused the industry to focus on methods available for the safe disposal of their defective aerosol units. Although there are wide variations from filler to filler, about 0.5% of filled aerosol cans are now considered as non-salvageable rejects. The percentage is higher for drug and cosmetic products because of FDA Current Good Manufacturing Practices (CGMP) and tigher quality assurance requirements; and lower for household products which are less stringently controlled. For example, in past years millions upon millions of aerosols, inadvertantly filled to slightly less than the prescribed net weight range, were simply "short-shotted' with a few grams of additional propellent to bring them up to the specification weight. Many marketers no longer permit this latitude. In fact, certain marketers no longer allow the dispensing of a few grams from aerosol products filled with a net weight slightly over the specified range. During production, reject cans collect at various points along the filling line: at the hot tank, the gassers, inspection stations near the end of the line, and so forth. Some of these cans will be recognized as leakers, others will be misfills, defective lithos, units with crushed valves and cans with pressure-induced deformations such as buckling. Where a rash of leaking cans is en-
250 The Aerosol Handbook countered, the potential for serious risk increases. Productions have been made where well over a thousand welded side seam leakers have been detected in the hot tank during one eight-hour shift. The rate of rejection (hour to hour) can vary widely in such instances, and the rate of leakage can vary from cans that produce a gas bubble every ten or twenty seconds to those best described as "gushers". Where rapid leakers are encountered, every effort should be made to remove them promptly to an outside area in order to prevent fires. Ventilation of the filling area (and obviously the gassing area) is also a vital attribute. Cans discarded after the gasser sometimes include leakers. In many cases, cans with misplaced valves will leak to emptiness in a few seconds. Some gassing rooms also house checkweighers, button tippers and other equipment. Rejects from these operations are generally non- leakers. Normally they are tossed into the reject barrel along with the gasser rejects. The use of a regular 30 to 55 gallon (110 to 200 liter) steel drum is commonplace, but ideally these receptacles should be pierced near the bottom with a number of 1 " to 2 " (25 to 51 mm) diameter holes in order to get any escaping hydrocarbon or dimethyl ether vapors out of the drum and into the ventilation system where they can be swept out of the area on a continuous basis. If powder-type or other electrostatically sensitive aerosols are being produced, it is a good idea to ground the drum with alligator clips. Once these drums of reject cans are taken to the outside for disposal, the question of the best disposal method must be addressed. In the past, such cans were often simply loaded into a parked dumpster and periodically hauled away to the nearest dumping site. For smaller operations, cans were often pierced by hand, using a hammer-like tool having a hardened steel pointed cone. Both of these options are now considered obsolete in today's more highly regulated society. Considerably more expensive methods must be employed. In the U.S.A. disposal procedures for aerosols must follow the EPA regulations under the Resource Conservation and Recovery Act of 1976 (RCRA), which were issued May 19, 1980. State and possibly local regulations must also be considered. The language of the federal regulations supports a legal opinion that fillers may puncture, crush, incinerate or otherwise "unseal" an aerosol container in a pre-disposal activity without the need to register with the EPA as a treater of hazardous waste. Aerosols are not listed by the EPA as hazardous wastes. Therefore, they may be considered as such only if they meet the characteristics of hazardous wastes identified in 40 CFR Part 161 (45 Fed. Reg. 33084). Four such general characteristics are listed. In addition, if the waste contains any of approximately 400 chemicals regarded as toxic, reactive or otherwise dangerous, then the waste will qualify as hazardous and persons who dispose of such materials must comply with the applicable hazardous waste management and permitting regulations or be subject to EPA enforcement action. The subject of reactivity of an aerosol dispenser has been studied. While aerosols do rupture if heated under confinement (as do cans of various beverages, packed vegetables and so forth), it has been determined that the apparent intent of Congress and the exact wording of the reactivity definition makes it impractical and unreasonable to interpret the reactivity characteristic to cover aerosol cans and other sealed containers. During late 1980, persons at the EPA concurred informally with this interpretation. While aerosol cans, in and of themselves, are considered as not subject to regulation as hazardous solid wastes, the contents of such cans must now be addressed. If they exhibit any of the characteristics of hazardous waste or are specifically listed as hazardous wastes, then those contents are subject to regulation. The flammability or explosivity of the contents must be considered, as well as the toxicity and acidity/alkalinity. As a general rule, it is thought that aerosols considered as non-flammable under the Federal Hazardous Substances Act of 1960 (FHSA) are not candidates for hazardous waste under the flammability or explosivity category. Aerosol oven cleaners that contain sodium hydroxide or potassium hydroxide are probably hazardous wastes from an alkalinity and corrosivity standpoint. If aerosol cans containing materials identified as hazardous waste are punctured or otherwise "unsealed" and the contents collected and subsequently shipped off-site for treatment or disposal, the facility ' 'unsealing'' the cans would be a generator of hazardous waste and subject to the requirements of 40 CFR Part 262 (45 Fed. Reg. 33140). On the other hand, if, after the cans are "unsealed" the contents are treated or disposed of on-site, the facility "unsealing" the cans would be a "treater" of hazardous waste (the contents) and be subject to the requirements of 40 CFR Parts 264 and 265 (45 Fed. Reg. 33154). While these statements
Aerosol Flammability 251 are based upon legal opinions current at the time of writing, firms having questions in this area should consult expert counsel for additional advice. A number of equipment options are available for the disposal of reject aerosol containers. They include can shredding (high and low speed), can piercing, can crushing, catalytic burning, incineration and so forth. A sophisticated can shredder called a Pulvermatic System is available from the Metal Box Engineering Division (Cheshire WA14 1TA, England) in the form of a turnkey operation. Cans are fed into the shredder via a special conveyor belt. The shredded solids then pass into a container below, while the liquid materials go into a companion drum. Any explosive gas is greatly diluted with ambient air using a ventilation system, after which it is discharged to the atmosphere. A second version of the device, which is quite a bit larger, handles 54 gallon (200 liter) drums which can be loaded with aerosol cans, boxes of tablets, or other items. The drums are tipped into the machine and the operation is then as just described. Both versions have been installed and are operating successfully. Similar devices are offered by the Hoveringham, Ltd. firm also of England. One is now in New Jersey and another in the Chicago area, in addition to devices in use within the U.K. The firm has arranged to pick up filled 54 gallon (200 liter) drums of aerosol waste, remove them to the disposal site, process them and invoice the filler on the basis of the number of drums submitted each time. A disposal unit under development by Kartidg Pak, Inc. (Davenport, IO) is reported to function on similar principles. At least one major U.S.A. filler/marketer uses a can crushing device, consisting of a heavy stone millwheel rolling against a track. The unit crushes areosol cans easily and the liquid portion of the product is then directed into a holding vessel nearby. Since the tank contents are saturated with hydrocarbon gases and have a boiling point of essentially the ambient temperature, there have been concerns regarding safe disposal. The device stands in a relatively remote outdoor location and should ignition occur in the crusher no damage would result. Can piercing is a fairly common disposal method. For example in the Cloud Manufacturing Company device, which is quite inexpensive, cans are fed down a metal tube, where they encounter a starwheel with sharp, penetrating points. The gases and liquids are drawn further downward and diluted with air. The ventilating system then emits the gas/air mixture to the atmosphere, while the liquid passes through a coarse screen and into a drum. The perforated cans are deflected by the screen and are collected into a second drum or bin. A can flattening device may be used to eliminate much of the bulkiness of the emptied units, after which they can often be sold as scrap for about $60 per ton ($66 per metric ton). In some piercing models cans enter a slot and are positioned for piercing. A ground bar swings into position on the row of cans. The piercing mechanism is hollow and contains inlet holes to enable the can contents to be withdrawn while the device is in the can up to the circular seal. The contents pass through the piercer under their own pressure and enter a vacuum exhausting chamber which is also heated to prevent chilling of the liquid, so that the propellent portion can be vaporized more completely and ventilated away. Sometimes nitrogen is introduced into the baffled chamber until the released propellent gases exceed the upper explosive limit (UEL), as monitored by a detection device. As before, the trapped liquids will contain some hydrocarbon gases and be extremely flammable. Two types of devices seem to be preferred for paints and coatings, which of course can be very messy when the can is breeched. The first is incineration. A heavy- duty furnace is available, where cans may explode from the heat without damaging the equipment. Conveyors are used to bring filled cans to the furnace and to periodically withdraw ruptured cans from the firebox. Depending upon air availability, these furnaces may produce heavy smoke from the combustion of solvents such as toluene and xylenes. Since heavy smoke can pose problems from the standpoint of the Clean Air Act and other regulations at both the federal and state levels, a few firms have considered the addition of catalytic converters to furnance exhaust systems. Catalytic converters are now used by one or two firms in New Jersey (a state with unusually severe environmental regulations) to convert exhausting hydrocarbon vapors into heat. The heat is then used for energy recovery. This type of system can be used for gas house vents as well as for the stack vents of can shredders, piercers and crushers. The second system considered for paint type products involves a pressure type crusher to be located in a safety disposal room similar to a gassing room. High forces and velocities are used at the crushing level to fully flatten the dispenser while jetting the contents
252 The Aerosol Handbook downward into a collection vessel. This device has been designed by a major paint filler/marketer and may be in operation shortly. The Can Disposal Committee within the Aerosol Division of CSMA has collected a large amount of specific data on methods for aerosol can disposal. They will be written and published by CSMA as an adjunct to their book tided'' Recommendations for die Safe Use of Hydrocarbon Propellents in the Plant and Laboratory".
AEROSOL TOXICOLOGY 253 8 Toxicology has been defined recendy as die science dealing widi die effects, antidotes, detection and odier aspects of die interaction of chemicals with various forms of life; or, more succindy, a study of die chemical facts of life. The chemicals we are talking about may be quite natural and normal in their origin, or they may be man-made substances that enter die body by ingestion, inhalation or even dirough the permeable barrier of die skin. In a great many instances chemicals are produced in situ, when the body is exposed to initiating substances or to radiation. Toxicity and toxicology should not be confused as to their meaning. The word ' 'toxicity'' is derived from die Greek word for poison and can be defined as the inherent capacity of a substance to produce injury. A related term, "hazard", indicates the probability that substantial injury will result from reasonably foreseeable uses. Hazard is thus the antidiesis of safety. All diese terms are relative. Nothing is completely non-toxic or non- hazardous. Pure water can be toxic to a drowning person, or irritating to die skin after long exposure. Pure air can be toxic to an individual with a severe case of the bends, or suffering from drastic hypothermia due to overexposure to cold air. Toxicity is a matter of dosage. Many trace elements, such as chromium and selenium, are vital to continued health, but are violent poisons if taken in large quantities. Some become carcinogens at higher dosage levels. Exposure to possible toxicity is sometimes a matter of choice, as in the smoking of cigarettes compared with non-smoking. The choice may be made by governments. For example, Canada has approved the use of cyclamates but banned saccharin in food products, whereas die reverse holds true in the U.S.A. Choices may often be made between product forms. Aerosol antiperspirants, for example, are often perceived as being more irritating to die respiratory tract than per-
254 The Aerosol Handbook sonal deodorants, and such problems can be avoided completely by the use of stick and roll-on alternates. In some instances there simply is no choice; one breathes the available air and drinks the available water, since corrections are either long term or unacceptable for various reasons. The toxicology of a substance must be examined from a large number of aspects in order to assure relative safety in use. For example, mineral oils and paraffins are used widely in topically applied products and sometimes in foods, but will produce lipid pneumonia when finely aerosolized and inhaled. Petroleum distillates also produce lipid pneumonia, while vegetable oils may bring about eosinophil pneumonia when atomized and breathed. Silicon dioxide (sea sand), when finely pulverized, is safe orally and topically, but prolonged exposure to even small amounts of the dust by inhalation causes silicosis (progressive pneumoconiosis). Aerosols are unique in that they may atomize rather safe materials that would never otherwise be inhaled. As a result, inhalation toxicology is an extremely important aspect of the toxicology of aerosols. Most toxicity experiments are divided into two main types: acute or short-term studies and chronic or long- term tests. Recendy the time differences between die two have blurred. New terms, such as sub-chronic testing, have been introduced to cover programs that take from about two-weeks to six months to complete in the laboratory. The longest chronic studies may require up to about 42 mondis: to 6 months for protocol development and other preparations; 24 mondis for exposure to rodents and/or other animals; and 12 mondis for padiological and histiopadiological examination of organs, report writing and so forth. Since diese massive undertakings involve perhaps 2,000 mice, rats, hamsters, dogs or combinations of mammals and take three Or four years to complete, they are done only in die case of important industrial chemicals. Methylene chloride was tested in diis manner during die years 1977-1981, because of early concerns expressed by die FDA. Dimethyl edier is now being tested similarly. Since these programs cost from $3 to $5 million each (1982 dollars) it is becoming quite common that companies widi a stake in the outcome will divide up die costs. Acute Toxicity In toxicology, die term ' 'acute'' means that exposure to a substance is limited to one day or less. In fact die dosage may be given all at one brief period. The results of acute studies are often given as LD5o (a lethal dose for 50% of die test animals) or as LC5o (a lethal concentration of gas or vapor in air, for 50% of die exposed animals). Related terms are ED50 and EC5o, the effective dose or concentration needed to bring about dizziness, irritation or some biological response odier dian mortality. Large numbers of animals are normally used to establish all these 50% levels with some statistical accuracy. If a small test program is planned, perhaps as a pilot study, the term ALD (average lethal dose) may be obtained on the basis of only six animals. These results, obtained, as they say, "at the drop of a rat", are useful to aerosol people only in a rough screening sense. An acute toxicity rating does not describe fully die safety or hazard of a substance. It fails to take into account die inhalation of essentially nonvolatile liquids and finely divided solids. It does not consider long-term effects, such as cumulative depositions. Or that old, weak or diseased persons may have much less resistance dian a group of young, healthy rabbits. And finally, that the toxicology of a complete aerosol formula may be quite at variance widi die weighted average toxicity of its component chemicals. Slightly over 60% of all U.S.A. aerosol products are regulated by die Consumer Product Safety Commission (CPSC), under its administration of the Federal Hazardous Substances Act (FHSA) and odier laws. The CPSC requires diat household products exhibiting special toxicity hazards must have these hazards identified on the label. Precautionary statements are normally included, telling die consumer how to avoid the hazard, and what to do if a toxicity problem arises as a result of misuse. In die formulation of such products certain relatively hazardous ingredients may be needed. If over 10% petroleum distillates, or 4% medianol, or 2% of sodium or potassium hydroxides are included, die product label must identify the presence of these items and list hazards diat may occur. Turpentine, certain acids and a few odier ingredients are handled similarly. In addition, household products should be tested clinically, using the protocols in the regulation as minimums. The clinical studies are: Toxicity (Oral, inhalation and dermal) CPSC 1500.3(b)(5, 6) Irritation (Skin and eyes- primary) CPSC 1500.3(b)(8) Corrosivity (To living tissue) CPSC 1500.3(b)(7) Strong Sensitizer (To living tissue) CPSC 1500.3(b)(9).
Aerosol Toxicology 255 The regulations do not actually specify that the studies be conducted, but any improperly labeled products are made subject to official actions, such as seizure and penalties. The rather cosdy skin sensitization test is not performed commonly unless there is reason to believe a problem may exist based upon background information. In 1982 me minimum cost of having die toxicity, irritation and corrosivity tests performed by a recognized clinical laboratory was about $1,500. Detailed 1981 prices are given in Table VIII. Anodier commanding reason for having such tests performed is the growing incidence of consumer complaints relating to clinical, flammable or other safety aspects of specialty products. One major marketer in the U.S.A. reported a growdi of from 5,000 consumer complaints in 1970 to almost 15,000 in 1980. In 1981, the British Medical Journal reported the major categories of acute poisoning in die U.K. for the years 1971 and 1979, showing a 117% apparent increase. This data is given in Table I. The apparent growth rate of consumer complaints in the U.S.A. and Canada has been even faster, aldiough here, as in the U.K., products have been made even safer over die past decade. The root causes of die problem are complex, but much of it can be related to die increasingly bad image of the chemical industry, as the result of poor coverage by the media. Press reports that are incorrect, scientifically unsound and often biased negatively may be good for the fourth estate, but diey gradually act to erode public confidence in industry. Nowhere is diis more evident dian in the chemical industry, which is now ranked lowest of all in public esteem. In 1981, only 29% of the general public and 43% of die diought leaders were favorably inclined to die Table I Major Categories of Acute Poisoning, 1971 & 1979 As reported to National Poisons Information Services, covering the United Kingdom and Republic of Ireland Product Category Drugs Household Agricultural Industrial Plant and Animal Miscellaneous Total 1971 Number 8,799 5,392 1,110 578 1,277 578 17,734 Reported Episodes % 49.6 30.4 6.3 3.3 7.2 3.3 1979 Number 19,486 11,124 2,275 2,192 2,179 1,170 38,426 % 50.7 29.0 5.9 5.7 5.6 3.1 chemical industry. Only 6% of the public and 4% of die diought leaders recognized diat it makes die biggest contribution to the national economy, and a mere 12% of die public felt that it makes die largest contribution to die "quality of life". Over 61% of the public and a clear majority of thought leaders condemned the chemical industry as having the biggest problems in die healdi, safety and environmental areas. Despite public opinion, the facts are given in a recent report by the U.S. National Safety Council: that die chemical industry has die nation's second best record of safety and health, just behind die aircraft industry. The aerosol industry, which is really a micro- segment of die vast chemical industry, has suffered a similar erosion of public confidence. As people become convinced diat products are hazardous or unreliable, diey look upon them more critically and increasingly report what diey feel may be problems. Particularly during the period of about 1978 to the present time (1982), complaint statistics maintained by a number of marketers have shown a doubling or more of the frequency. The rise in complaint level does not seem to be product or package oriented. (See Table III of the Aerosol Marketing chapter.) A 1981 U.K. survey showed that 29% of hair spray users and 33% of air freshener users made spontaneous criticisms of aerosols when asked of their general feelings about die products. For die hair spray users 7% felt aerosols were harmful to health, as an unsolicited comment. When asked if aerosols were harmful to healdi, 14% said yes and 12% said no. For the air freshener customers, 3% felt aerosols were health hazards, unsolicited. When directly asked if they thought aerosols were harmful to health 5% said diey were and 26% replied that diey were not. In bodi groups, adverse environmental effects ranked about equally widi health concerns (die U.K. still uses CFC propellents), but die greatest disadvantage mentioned (by 23% of bodi groups) was that the dispensers would not spray; e.g. nozzle blockage or odier problem. In die U.S.A. a published consumer attitudinal survey was recendy conducted among users of various aerosol products. Considering only the hair spray category, die results of interviews with about 2000 users, recent users and non-users are shown in Table II on die next page. Several industry observers have looked at data such as diis and have suggested that, while flam- mability/explosivity of aerosols may have constituted
256 The Aerosol Handbook the great challenge of the 1970s, toxicological considerations may be the most controversial issue of the 1980s. Considering only the current hair spray users, Table II suggests that 29% identified aerosols as having specific types of toxicity, against only 12% who were concerned about flammability/explosivity. Within the specified toxicity grouping, both users and non-users of aerosol hair sprays felt that inhalation toxicity was by far the most serious problem with these products. Starting about 1977 the U.S. Environmental Protection Agency (EPA), which regulates about 12% of all domestic aerosol products, followed the lead of the CPSC regarding the labeling of insecticides, disinfect- Table II Consumer Attitudes Problems with Aerosol Hair Sprays Respondant Base Have seen or heard of problems with aerosols Problems: Harmful/pollute environment/ bad for ecology Destroys/uses up ozone/ damages ozone layer Hydrocarbons/fluorocarbons pollute air Hydrocarbons/fluorocarbons endanger or destroy ozone Other (unduplicated) ecological dangers Current Hair Spray Users 912 _%_ 64 15 18 2 4 39 Use an Aerosol Hair Spray 636 _%_ 64 18 14 1 1 34 Use a Non-Aerosol Hair Spray 464 %_ 71 17 16 3 3 39 Dangerous or harmful to health 2 2 3 Aerosols are linked to cancer 4 4 4 Fumes are dangerous if inhaled 5 6 6 Bad for lungs/irritate/cause lung damage 14 11 14 Irritate the eyes 4 3 3 Dangerous in home/may explode/flammable 12 13 15 Other (unduplicated) health hazards 35 34 39 Won't work/won't spray/get stuck Nozzle clogs Wasteful/lose propellent/can won't empty Other (unduplicated) problems with can 7 5 7 18 9 6 7 20 8 6 8 24 Source: Hair Spray Usage and Attitude Study, privately funded, April 1979. ants, insect repellents, herbicides and like products according to toxicological hazard. They established Toxicity Category I, II, III and IV, according to the results of five clinical tests, as outlined in the Code of Federal Regulations, Title 40, Ch. 1, 162.10(h)(l & 2): Oral LD50 Inhalation LC5n Dermal LD5o Eye Effects — such as irritation or corrosion Skin Effects — such as irritation or corrosion Toxicity Category I, where the minimum front panel precautionary language must read: "POISON. Keep out of reach of children. Read carefully cautions on back (or side) panel.", is defined on the basis of oral, inhalation or dermal toxicity (as distinct from skin or local eye effects) and will almost never be encountered in the form of aerosol pesticides. Front panel labeling for Toxicity Category II substances must begin with the word "DANGER"; while the other categories use the words "WARNING" or "CAUTION". The EPA also requires label warnings where certain active chemicals are used, such as specific organophos- phates; plus the stipulation of particular inert ingredients, such as nitrites, which may react with diethanola- mine and certain other nitrogen compounds to form traces of N-nitrosamines, a few of which have now been identified as animal carcinogens. Formulas containing both nitrite and morpholine have been denied product registration on the basis that toxic N-nitrosomorpholine would probably form in the dispenser over a period of several months. Vitamin C and some other substances are said to inhibit the formation of N-nitroso compounds but it is doubtful if any aerosols have utilized this technology. Under the provisions of the Poison Prevention Packaging Act of 1970 (PPPA), the CPSC has required the use of child-resistant closures for both specific compositions and in general those that are unusually toxic. The criteria for such packages are that they must be resistant to being opened by at least 85% of a group of not less than 200 children, aged 42 to 51 months, who are given five minutes to open the product. For those unable to do so, a visual demonstration without verbal explanation is given. After this, 80% must still be unable to open it. Conversely, at least 90% of adults must be able to open the package and resecure it within five minutes.
Aerosol Toxicology 257 Specific formula types mentioned in the PPPA include products with 2% or more of sodium hydroxide or potassium hydroxide (as in most aerosol oven cleaners), and those with more than 10% ethylene glycol, Where two or more sizes are offered, any one size product may be sold in a non child-resistant packaging form. The rule was designed to allow for the special needs of persons with eyesight problems, arthritis and so forth in childless households. Some marketers have used this part of the regulation too liberally, by providing their most popular package size in the standard, easy-to- open form. Between 1970 and 1980 the number of accidental poisonings of children under the age of five dropped from 7.0 million to 2.6 million, a decrease of 63%, and fatalities dwindled to 151 in 1980. Some of these 1980 statistics related to certain pesticides, and this prompted the EPA to establish their "special packaging" rules, effective March 9, 1981. In regard to child-resistant packaging, a pesticide's toxicity places it in one of three categories: (1) those products which clearly match or exceed the toxicity criteria in the Federal Register, Tide 40, 162.16(c)(2) and which must use child-resistant closures unless exempted, (2) products for which existing toxicity data are not precise enough to determine if child-resistant packaging is needed, and where such packaging is required until vindicating data might be developed, and (3) those products which clearly do not meet die toxicity criteria. In practice, nearly all aerosol pesticides designed for consumer use are sufficiendy innocuous mat special packaging is not required. The status can be determined readily by reviewing the results of the clinical studies now required as a part of the documentation that must accompany every Application for Product Registration. In die case of diose pesticides registered before such studies were mandated, die marketer may have die tests performed, or alternately follow die advice of qualified firms (such as toxicant suppliers), consultants or odier knowledgeable persons regarding packaging. Should the marketer elect to use a child- resistant closure, it must conform to die established testing standards, regardless of the relative toxicity of the product. Definitions of a " toxic substance " can be expected to vary, especially between countries; but in the U.S.A. the federal agencies and dieir state counterparts have agreed on two levels of toxicity, and their definitions are essentially identical, although often worded radier differently. The most recent definitions are shown here, taken from die Toxic Substances Control Act (TSCA): a. A "Highly Toxic Material"means: i. A chemical substance or mixture that has a median ledial dose (LD5o) of 50 mg or less per kg of body weight when administered orally to young adult laboratory rats; or ii. A chemical substance or mixture diat has a median ledial dose (LD5o) of 200 mg or less per kg of body weight, when administered by continuous contact for at least 24 hours on die bare skin of one mammalian species, preferably young adult albino rabbits; or iii. A chemical substance or mixture that has a median lethal concentration (LC5o) in air of 200 ppm by volume or less of gas or vapor, or 2 mg per liter of mist, fume, or dust when administered by continuous inhalation for at least one hour to young, adult laboratory rats. b. A "Toxic Material" means: i. A chemical substance or mixture diat has a median lethal dose (LD5o) of more dian 50 mg/kg but less than 500 mg/kg of body weight when administered orally to young adult laboratory rats; or ii. A chemical substance or mixture that has a median ledial dose (LD5o) of more dian 200 mg/kg, but not more than 1,000 mg/kg of body weight when administered by continuous contact for at least 24 hours on die bare skin of one mammalian species, preferably young, adult albino rabbits; or iii. A chemical substance or mixture that has a median ledial concentration (LC5o) in air of more than 200 ppm but not more than 2,000 ppm by volume of gas or vapor, or more dian 2 mg per liter but not more than 20 mg per liter of mist, dust, fume, or dust when administered by continuous inhalation for at least one hour to young, adult laboratory rats. For aerosols, die only significant route into die body is via inhalation. Respiration of aerosol mists appears to be connected with about 99%. of all toxicological problems widi aerosols—real or imagined. Some early work on inhalation toxicity of individual compounds was
258 The Aerosol Handbook done by Carpenter, C.P. et al and reported in die J. Ind. Hyg. & Tox. 31(8), 343 (1949), using Sherman albino rats, and noting die concentration of vapors required to kill 2, 3 or 4 out of 6 rats widiin a 14 day period following a 4 hour exposure. This data is given for diose compounds found in aerosol formulations; see Table III. The most toxic aerosol compounds were epichlorohydrin and formaldehyde, which had an approximate LC5o of 250 ppm under die conditions of test. The use Table III Acute Inhalation Toxicity of Aerosol Propellents and Solvents Substance P-ll P-12 P-113 P-114 P-22 P-134a P-142b P-152a 1,1 -Difluoroethylene 1,1 -Dichloroethylene Propane n-Butane isoButane n-Pentane isoPentane n-Hexane n-Heptane Dimethyl ether (DME) Nitrous Oxide isoPropanol Toluene Cychlohexanone Trichloroethylene Methylene chloride 1,1,1 -Trichloroethane "Cellosolve" Solvent "Cellosolve" Acetate Methyl "Cellosolve" Acetate Tetrachloroethylene Carbon tetrachloride*** Trichloroethylene Methyl ethyl ketone Ethyl butyl ketone Epichlorohydrin Formaldehyde Vapor Concentration in Air (v%) AL.C* LCo LC30 CL100 — — — — — — 6.4 12.8 3.2 — — — — — I 1.6 0.8 0.8 0.8 0.4 0.2 0.8 0.4 0.4 0.8 0.2 0.2 0.025 0.025 — — 60 >30 — — 32 s.a.** >24 36 — — >6 >3 s.a.** — >4 >2 — — — — — 2.62 62 6 70 35 56.7 12.8 40 s.a.** 34 52 11 16 — — 16.4 s.a.** z — — — — — ~8 80 — >80 <40 — — — s.a.** 45 65 — — — — s.a.** — — — — — — Where two or more animals were tested the lowest results were reported. All data must be considered approximate, due to differences in chemical purity, techniques, etc. •Average Lethal Concentration (6 rats; 2/6, 3/6 or 4/6 deaths). "Simple asphyxiant, although narcotic and other effects may occur. ***This and a few other substances are included for comparisons, although no longer used in aerosol formulations. of epichlorohydrin in aerosols (mainly as a water scavenger, where easily hydrolysed chemicals were also present) has now almost vanished. Typical formulation levels were 0.075%. Formaldehyde, as die 37% HCHO "Formalin" solution in water, is used at about 0.100% of the solution, or 0.037 % as die gaseous compound, as a broad spectrum preservative. But now, widi die recent bad publicity formaldehyde has received as a suspected low-order carcinogen, its use in aerosols is diminishing rapidly. The audior is unaware of any acute toxicological problems associated with the use of either of these chemicals as aerosol ingredients. Cardiac Arrhythmia At least as far back as 1957 the medical profession began to realize that a wide variety of volatile solvents, including some aerosol propellents, were able to cause cardiac sensitization when inhaled in higher concentrations. The sensitized heart loses its normal rhythm and develops various arrhyuimias, characterized by a more rapid, weaker ventricular pulsation and accompanied by a reduction in myocardial force and other hemodynamic effects. This abnormal rhyuim may be reversed without damaging the heart, or it may progress to total cardiac disarray and irreversible cardiac arrest, inevitably followed by death from congestive heart failure. Once the heart is placed in the metastable arrhyuim- ial condition, a further stimulation, such as an unexpected loud noise, a slap or a bright light, can serve to bring about a condition of intolerable sensitization, with cardiac arrest and death. This may also be done with the injection of known heart stimulants, such as atropine and (more commonly) epinephrine, at doses of about 6 to lOfig/kg. In clinical studies designed to determine threshold concentrations needed to produce cardiac arrhythmia (ECo) or cardiac arrest and death (LC0), it is common practice to anesthetize dogs or other animals, to eliminate the effect of outside influences, then inject with epinephrine, and then start the exposure phase, which normally lasts only 5 to 10 minutes. A summary of cardiac arrhythmial and arrest responses is provided in Table IV. The aerosol industry first encountered the cardiac arrest syndrome about 1960 with the introduction of a cocktail glass chiller product in California. The composition was 100% P-12. Teenagers (average age 17 years) concentrated the vapors by various means, some quite ingenious, and then breathed them deeply several times in order to achieve a psychodelic. "high". The
Aerosol Toxicology 259 euphoric period lasted from about 60 to 480 seconds, depending upon dose, often followed by a trough or rather depressed period. The glass chiller was quickly withdrawn, but this merely caused the youths to evaluate other products. Those high in CFC content and relatively free from messy or irritating concentrates were the primary targets. Although at least twenty different aerosol products have been reported in these episodes, the frypan lubricant (then 97% CFCs) and antiperspir- ant (then 90% CFCs) were used the most widely. But Table IV Incidence of Cardiac Arrhythmia due to Propellent Inhalation (Using dogs, anesthetized and injected with about 6(tg/kg of epinephrine as a cardiac stimulant to stimulate conditions of stress response.) Concentration of Propellent (v%) Threshold to Threshold to Propellent Produce Cardiac Produce Cardiac Tradename Formula Arrhythmia, EC0 Arrest, LCo •Hamsters and rabbits gave threshold (ECo) values of about 4%. **Non-sensitized dogs gave ECo values of 5% and exercized dogs had ECo values of 10%. •••Test run on anesthetized monkeys, anesthetized and sensitized mice, dogs, etc. ••"Tests run using 99.7% He and 0.3% Oi at 122 atmos. (12.3 MPa) showed no ill-effects. n.a. = non-applicable. even such unlikely formulations as black paint aerosols (then about 55% CFCs) were implicated. The industry reacted in a variety of ways, many of them public relations oriented, and including the education of specific thought leaders: police chiefs, high- school principals and teachers, team coaches, and public service workers, on the serious implications of "sniffing" or "huffing" aerosol products. Despite these efforts the problem continued, becoming quite notorious in the late 1960s. It was made a topic of the first formal hearing by the newly formed Consumer Product Safety Commission, held in 1973. During the early 1970s, teenagers discovered that sniffing the toluene in aerosol paints would provide a longer and more satisfying ' 'high.'' By this time nearly all paints had changed from CFC to hydrocarbon propellents, so the transition to these products acted to curtail the number of deaths resulting from gross product misuse. During the 1976 to 1978 period, when aerosols were reformulated to CFC-free systems because of pending government regulations related to the CFC/ozone controversy, the problem finally went away. The "sniffing" of paints still continues and may even be increasing in the southwestern U.S.A., but few if any deaths result from this form of abuse. Similarly, medical students, hospital orderlies and other persons having access to nitrous oxide have turned to deliberately sniffing this gas for its euphoric effect. After one deep draught of the gas, plus an imbibition period of 15 to 30 seconds, users experience an exhilarating "high" lasting about 120 to 200 seconds. The state is prolonged with rebreathing. Aerosol cans containing whipped creams have been used for similar purposes. In one celebrated case, an elderly couple used up as many as 100 cans in one session, and averaged about three or four episodes per week. A number of serious side effects usually accompany this type of physical and mental abuse. Biotransformation (metabolism) Once they have entered the body, many chemicals are eliminated unchanged. The process is most rapid with gases or highly volatile solvents, where most of the elimination takes place via the lungs. Less volatile compounds are voided through the urine, feces and even through the skin in some cases. In a few cases bio- accumulation will occur, such as with lead compounds, which concentrate in the skeletal structure and bone marrow with serious long-term consequences. The drastic limitation of lead-containing compounds in aerosol paints relates to concerns of this type. P-11 P-12 P-21 P-22 P-31 P-32 P-113 P-114 P-115 P-123 P-124 P-132b P-134a P-142b P-152a P-C318 Carbon Tetrachloride Methylene chloride Propane isoButane n-Butane isoPentane Dimethyl Ether Nitrous Oxide Nitrogen Helium CC13F CC12F2 CHC12F CHC1F2 CH2C1F CH2F2 CC12F.CC1F2 CC1F2.CC1F2 CC1F2.CF3 CHC12CF3 CHCIFCF3 CC1F2.CH2C1 CH2FCF3 CH3CC1F2 Co3'CHF2 cyc.C,FB CC1, OH2Cl2 C3H8 C«Hio C«Hio CsHi2 CH3OCH3 N20 N2 He 0.5 to 1.0* 2.5 to 5.0" 0.5 to 1.0 2.5 to 5.0 2.5 to 5.0 20 to 25 0.5 to 1.0 2.5 15.0 1.0 to 2.0 1.0 to 2.0 0.25 to 0.50 7.5 2.5 to 5.0 13.0 to 15.0 25.0 0.5 0.5 >20.0*" 10 to 20*** 10 to 20*** 5 to 10*** 20 >80*** >80*** >80**** 0.5 2.5 0.5 to 1.0* to 5.0" — — — — to 1.0 5.0 — 1.0 to 2.0 1.0 to 2.0 — — — — — — — — <15 n.a. n.a. n.a.
260 The Aerosol Handbook I O2 insertion, via I H-C-Cl Cytochrome P-450^ h-C-CI Methylene chloride** H-C-Cl Rearran«es % H-C- I I Formyl chloride intermediate H-C-OH RearrmHes *"> H-C-H Formaldehyde H-C-Cl I Figure 1. Biotransformation of Methylene Chloride *Up to about 1.5% of this and other uncharacterized reactions may occur. No formic acid (HC02H) is formed. "Commercial product; 97.8v% methylene chloride and 2.2v% inhibitors, not considered. Other chemicals may be susceptible to reaction with enzymes and odier biological factors, so drat various percentages are metabolized into new compounds. The process is usually one of progressive oxidation, so that energy can be produced for the body. Catabolism, die formation of simpler compounds, will sometimes occur. It is a form of destructive metabolism. Conversely, ana- bolism (constructive metabolism) may take place, widi the generation of more complex substances. Many of these processes take place in die liver in die presence of die microsomal monoxygenase system or NADPH. Cytochrome P-450 dependent reactions are involved also; for instance in die oxidation of secondary alcohols drat do not undergo ordinary /3-oxidation. In die case of saturated CFCs, biotransformation is eidier insignificant or absent. They are excreted mainly via die lungs, more or less in relation to dieir volatility. The hydrogenated CFCs or FCs (such as P-152a) may be metabolized to a small extent, based upon such evidence as increased urinary fluoride. Methylene chloride, once inhaled, is 78 to 93% eliminated in the breath during the following two hours, and 98% is excreted by various routes during the first 24 hours after exposure. Approximately 94% is unchanged; the other 6% is metabolized, as shown in Figure 1. Except for their obvious ability to oxidize by combustion, the saturated hydrocarbons are characterized by their chemical inertness; nevertheless, they can be metabolized by die body. Propane is probably biotrans- formed to some minute extent in animals, but no specific studies have been performed. The butanes are metabolized by rodents, but no tests have been made in man. Similarly, the pentanes, hexane and heptane are metabolized, leading to a variety of alcohols, ketones, and odier compounds, as shown in Figure 2. Figure 2. Biotransformation of n-Hexane Note: n-Heptane displays similar metabolic pathways, although more complex due to greater chain length and asymmetry. CH3-CH2-CH2-CH2-CH2-CH3 n. Hexane Monoxygenase system in animal liver microsomes. CH3-CH2-CH2-CH2-CH2-CH2 OH 1-Hexanol CH3-CH2-CH2-CH2-CH2-C* 1-Hexanal CH3-CH-CH2-CH2-CH2-CH3 =5= OH 2-Hexanol (Main reaction product.) I CH3-CH-CH2-CH2-CH-CH3 "5= OH OH 2,5-Hexanediol CH3-C-CH2-CH2-CH2-CH3 O Methyl n. butyl ketone CH3-C-CH2_CH2—CH-CHo O OH 5-Hydroxy-2-hexanone CH3-CH2-CH-CH2-CH2-CH3 OH 3-Hexanol CH3-CH2-CH2-CH2-CH2-C Hexanoic Acid sOH (5-oxidation of fatty acids via cytochrome P-450 dependent reactions. CH3-C-CH2-CH2-C-CH3 O O 2,5 -Hexanedione n. Heptane displays similar metabolic pathways, although more complex due to greater chain length and asymetry.
Aerosol Toxicology Biotransformations are of extreme interest to the toxicologist, since in some cases mutagenic or carcinogenic chemicals may be formed. In other instances, chemical reactions may occur which have nothing to do with metabolic processes, but may be significant to health. For example, as mentioned previously, nitro- samines form with extreme ease by the reaction of sec. amines and certain tert. amines with either nitrous acid (HONO) or its various salts. The most important salt is sodium nitrite (NaN02). However, sodium nitrate (NaN03) is present in the body to various extents and may be changed to the nitrite form by the action of nitrogen-reducing bacteria. Nitrosamine formation can be catalysed by formaldehyde (HCHO) and thiocya- nate ion (SCN~) and inhibited by ascorbic acid (Vitamin C) and sometimes by dl. tocopherols (Vitamin E). Many nitrosamines are bodi mutagenic and carcinogenic agents. It is prudent to avoid die use of sec. and tert. amines in aerosol sprays which could be inhaled, since this would act to eliminate any in vivo production of possibly dangerous nitrosamines. During the 1970s, certain groups attempted to place labeling or other sanctions on products containing methylene chloride, stating that the catabolically produced carbon monoxide (CO) reacted quickly with hemoglobin (He) in the blood to produce carboxy- hemoglobin (COHe) in dangerous amounts. Investigations showed that levels as high as 20% COHe acted to induce headache and nausea, and could be potentially dangerous for persons with coronary heart disease But such level would never be approached except under die most flagrant conditions of product misuse. Normal levels of COHe range between about 0.5 to 2.0%, but can be increased by smoking or exposure to carbon monoxide from other sources. In a particular test, an aerosol was sprayed into a small, unventilated area to establish a concentration range of 65 to 200 ppm in air, except for a 500 ppm peak, lasting less than 30 seconds. People with pre-test COHe values of 1.1 to 2.1 % were exposed to this treated air space, after which dieir COHe levels changed to a rather uniform 2.1%, indicating an insignificant increase. A study of beauty salon operators working all day in a Time Weighted Average (TWA) of 6.1 ppm methylene chloride showed a 1.4% elevation of COHe over baseline levels. A consumer aerosol paint remover was used to emptiness in a room widi extremely poor ventilation, resulting in a methylene chloride concentration of 80 to 90 ppm in air at the breathing zone and localized peak concentrations of 534 ppm (after 3 minutes) and 698 i i \ \—i—, i i \ \ \ \ i—,—i—.—,—,—\ > i > ,—j 1 1 0 2 4 6 8 10 12 14 W 18 20 22 24 26 28 30 TIME SINCE BEGINNING OF EXPOSURE (HR) Figure 3. Chart of Exposure to Methylene Chloride Per cent COHe in the blood as a function of exposure to a continuous net level of 180 to 200 ppm of methylene chloride during 8-hour workdays. Tests based on an average of seven men (non-smokers). ppm (after 5 minutes) from the end of the spray period. For safety purposes this type of scenario should be avoided when using such products. In one other test, the consecutive use of three hair spray aerosols in a 4'x6'x8' (2.23 m2) bathroom resulted in the production of an average of 102 ppm of methylene chloride vapors in air across the 15.5 minute period following the last spraying episode. While this situation could be hazardous to some persons, it is strongly magnified from reasonably foreseeable circumstances, where only one can would be sprayed, a larger bathroom would be used, the door would be open, and the person would normally leave the area after spraying the hair. In a recent decision die CPSC determined that no sanctions should be placed on aerosols containing methylene chloride as a result of possible COHe formation in die body. A final example shows that men exposed to about 190 ppm of mediylene chloride vapors continuously in me workplace developed peaks of about 8.35% COHe in the blood, provided they did not smoke. There was about a 74% return to the pre-exposure baseline overnight. These data are elaborated in Figure 3. Acceptable Limits of Exposure In the U.S.A. the first formal approach to die control of chemical vapor inhalation in die workplace was taken by the American Conference of Governmental Industrial Hygienists (ACGIH) about 1939. They established me concept of the Threshold Limit Value (TLV) as the maximum to which it was believed workers could be exposed, day after day, without adverse effects. In
262 The Aerosol Handbook 1968, these values became legal limits under the Walsh - Healey Act. They were picked up in 1971 by the newly formed Occupational Safety and Health Administration (OSHA), when they adapted a host of industrial consensus standards in writing their regulations. A term of almost synonymous significance is the Time Weighted Average (TWA) airborne concentration of mists, vapors or gases in the workplace. They are usually numerically identical. They are generally expressed in both ppm or mg/m3 of contaminant, with a maximum level established as 1,000 ppm, except for the special case of carbon dioxide which is higher. TLV or TWA values in one system of measurement can be converted to the other by an easy calculation; for instance a figure of 500 ppm for n-heptane is equivalent Table V Threshold Limit Values (TL V)for Various Aerosol Propellents and Solvents Vapor in Workplace Air p-n P-12 P-22 P-113 P-114 P-115 Propane n-Butane isoButane n-Pentane isoPentane n-Hexane n-Heptane Dimethyl ether (DME) Carbon Dioxide Methylene Chloride - Inhibited Ethanol Isopropanol 1,1,1-Trichloroethane - Methyl isoButyl Ketone Diethyl Ether (DEE) Monoethanolamine Inhibited (MIBK) Odorless or Low-odor Kerosene Toluene Xylenes TLV* (ppm in air) lo000** 1,000 1,000 1,000 1,000 1,000 1,000 600 800*** 500 500 500 500 1,000 1,000 500 1,000 400 500 100 400 3 500 200 100 (100) (100) (75) *OSHA values, usually the same as Time Weighted Average (TWA) values. ** Except for the special case of carbon dioxide, the highest TLV or TWA recommendations are 1,000 ppm. or 0. lv%. ***isoButane is listed but no value is specified. 800 ppm is an estimate. Values in parentheses are those of the National Institute of Safety and Health, indicated when different from the TLVs. Other values, such as those by the EEC for MAC, and those currently proposed by the ACGIH, may be even lower. to 1,800 mg/m3. TLV figures for various common propellents and solvents are shown in Table V. The National Institute of Safety and Health (NIOSH) functions in an advisory capacity to such agencies as OSHA and the EPA, and they frequently propose revisions in the TLV/TWA values in accordance with current clinical findings and consensus opinions. For instance, they have now asked for a reduction to 50 ppm in the case of n-hexane (consistant with the European MAC value) which recognizes such recent findings as (1) 100 ppm can cause neuropathy in chickens after 4 to 5 weeks of continuous exposure, (2) 250 ppm causes mild neuropathy in the mouse after 6 d/wk for one year and (3) workers exposed to 500-1000 ppm 8 hr/d showed impaired sensory perception, loss of strengdi, muscular atrophy and other factors that continued for up to one year after exposure was removed. The proposed level of 50 ppm would provide a safety factor of approximately ten-fold. Many TLV/TWA listing include an extra allowance for short term exposures. Although both n-hexane and n-heptane are listed as 500 ppm for 8 hour exposure averages, concentrations of 1,800 ppm are allowed for periods to 15 minutes. In the case of ethylene glycol monomethyl ether (EGMME), CH3O.CH2.CH2OH, the OSHA TWA is 25 ppm, while the ACGIH has a Permissible Exposure Limit (PEL) of 25 ppm 8-hr TWA and a Short Term Exposure Limit (STEL) of 35 ppm for any 15 minute excursion. Those wishing to determine the TWA value for particular chemicals may consult the U.S. Federal Register 29 Sec. 1910.1000 in the OSHA regulations. Material Safety Data Sheets An easier way to determine TWAs plus a great deal of other toxicological information is to refer to a Material Safety Data Sheet, OSHA Form 20, or forms essentially similar, which have been approved by the U.S. Department of Labor. An example of a properly filled out form is shown as Table VI (Pages 263, 264), except for the deletion of the manufacturer and relevant data. Around 1974 the aerosol industry recognized a need for such a form for aerosol products. A special task force under the aegis of the CSMA Aerosol Division developed a "Material Safety Data Sheet for Pressurized Products" during the following year and had it approved by the government as one essentially similar to the OSHA-20 form. This two-page form is shown as Table VII (Pages 265, 266). (continued on page 267)
Aerosol Toxicology 263 Table VI MATERIAL SAFETY DATA SHEET (Approved by U S Department of Labor Essentially Similar" to Form LSB-00S-4, CHEMICAL NAME: ETHANOL, 200 PROOF SYNONYMS: Ethyl Alcohol, 200 Proof CHEMICAL FAMILY: Alcohols FORMULA: CjHsOH MOLECULAR WEIGHT: 46.07 TRADE NAME AND SYNONYMS: Ethanol, 200 Proof; Ethyl Alcohol I. PHYSICAL DATA BOILING POINT, 760 mm. Hg SPECIFIC GRAVITY (H20=1) VAPOR DENSITY (air =1) PER CENT VOLATILES BYVOLUME APPEARANCE AND ODOR 78.3°C. (172.9°F.) 0.7905 at 20/20°C. 1.6 at 78.3°C. 100 FREEZING POINT VABOR PRESSURE at 20°C. SOLUBILITY IN WATER. % by wt. at 20°C. EVAPORATION RATE (Butyl Acetate = 1) -114.1°C. 44 mm. Hg Complete 3.30 Water-white liquid; characteristic odor. II. HAZARDOUS INGREDIENTS MATERIAL Not applicable % TLV (Units) III. FIRE AND EXPLOSION HAZARD DATA FLASH POINT (test method) 70°F., Tag open cup FLAMMABLE LIMITS IN AIR, % by volume EXTINGUISHING MEDIA SPECIAL FIRE FIGHTING PROCEDURES UNUSUAL FIRE AND EXPLOSION HAZARDS AUTOIGNITION TEMPERATURE LOWER 4.3 793° F. UPPER 19.0 Carbon dioxide or dry chemical for small fires. "Alcohol"-type foam for large fires. Addition of water may reduce intensity of the flames. None EMERGENCY PHONE NUMBERS JohnD. Doe 217-443-1400 Jane D. Buck 217-444-1400 Legal responsibility is assumed only for the f=»ct that all studies reported here and all opinions are those of qualified experts ABC Corporation, 555 Western Avenue, Chloago, IL 60699
The Aerosol Table VI - Continued Side 2 of Material Safety Data Form IV. HEALTH HAZARD DATA THRESHOLD LIMIT VALUE EFFECTS OF OVEREXPOSURE EMERGENCY AND FIRST AID PROCEDURES 1,000 ppm. Swallowing liquid causes inebriation, headache, nausea, and vomiting. Liquid causes eye irritation. Breathing of vapors may cause drowsiness. Flush skin and eye contact with plenty of water. If inhaled, remove to fresh air; give artificial respiration if breathing has stopped. Call a physician. If swallowed, induce vomiting. V. REACTIVITY DATA STABILITY UNSTABLE — STABLE V INCOMPATIBILITY (materials to avoid) HAZARDOUS DECOMPOSITION PRODUCTS HAZARDOUS POLYMERIZATION May Occur Will not Occur V CONDITIONS TO AVOID Avoid heat, sparks, and fire. None Thermal decomposition may produce carbon monoxide and/or carbon dioxide. CONDITIONS TO AVOID None VI. SPILL OR LEAK PROCEDURES STEPS TO BE TAKEN IF MATERIAL IS RELEASED OR SPILLED WASTE DISPOSAL METHOD Flush heavily with water. Incinerate in a furnace. VII. SPECIAL PROTECTION INFORMATION RESPIRATORY PROTECTION (specify type) VENTILATION LOCAL EXHAUST MECHANICAL (general) PROTECTIVE GLOVES OTHER PROTECTIVE EQUIPMENT None required Preferable Acceptable SPECIAL OTHER None required PROTECTION Goggles Eye bath and safety shower VIII. SPECIAL PRECAUTIONS PRECAUTIONARY LABELING OTHER HANDLING AND STORAGE CONDITIONS ETHANOL, 200 PROOF On the basis of the toxicological, physical, and chemical properties of ETHANOL, 200 Proof, precautionary labeling used on the containers is as follows: FOR INDUSTRY USE ONLY — Printed in U.S.A.
Aerosol Toxicology 265 Table VII MATERIAL SAFETY DATA SHEET FOR PRESSURIZED PRODUCTS s 1-3 o fa SECTION I - PRODUCT IDENTIFICATION COMPANY NAME ADDRESS Regular Telephone No. Emergency Telephone No. PRODUCT TRADE NAME OR BRAND NAME OTHER PRODUCT DESCRIPTION OR IDENTIFICATION SECTION II - HAZARDOUS INGREDIENTS INGREDIENT CHEMICAL NAME TYPE OF HAZARD(S) APPROXIMATE WEIGHT % SECTION III - PHYSICAL DATA TLV VALUE OTHER TOXICITY INFORMATION BOILING POINT ©101.3 kPa (760mm Hg) VAPOR PRESSURE MAXIMUM @ fy.'fc (130°F) VAPOR DENSITY vs. AIR«=1 ®15-32°C (60-90°F) ( )Not Applicable "C ( kPa Psig) °F) Heavier= >1.0 Lighter^ <1.0 SOLUBILITY IN DEIONIZED WATER (Weight % @10°C/50°F) SPECIFIC GRAVITY/DENSITY (vs. water (a^°C/39.2°F) PERCENT VOLATILES (Ambient/21°C/70°F) APPEARANCE AND ODOR (Description of spray and resultant residue) BNegligible=< ,\fo Slights EVAPORATION RATE (vs. n-Butyl Acetate=l) .1-1.( B ( }Not Applicable Mg/m3 Approximately by Volume Moderate= 1-1C$ Appreciable^ B Not Applicable <1.0 ( ) >1.0 ( )Complete % by Wt. FLASH POINT (minimum) Method-. SECTION IV - FIRE AND EXPLOSION HAZARD DATA ( )Not Applicable FLAMMABLE LIMITS IN AIR Vol. % @ °C? °F) ( )Not Applicable LEL-UEL= %_ EXTINGUISHING MEDIA":"(_JNot Applicable (will not burn below S,\S°Q/\,s6o°T) 8Water Fog Qstandard Foam Qspecial Alcohol-Stable Foam QCarbon Dioxide-C02 Dry Chemical ( )Speciali SPECIAL FIREFIGHTING PROCEDURES: Keep containers cool. Use equipment or shielding required to protect personnel against bursting, rupturing, or venting containers. UNUSUAL FIRE AND EXPLOSION HAZARDS: At elevated temperatures (over 5*+oC/l30°F), containers may vent, rupture, or burst. Also see Section VI. **Additional Notes or Comments from sections above: a o >-3 as 3 o o c o i-3 o w o as (Continued on Side Z) Date Filled Out: ; Prepared or Approved by: THIS FORM APPROVED BY THE U.S. DEPARTMENT OF LABOR AS "ESSENTIALLY SIMILAR" TO OSHA-20. Unless noted otherwise, all information given is on ths total product, including propellsntsr
266 The Aerosol Handbook Table VII* - Continued MATERIAL SAFETY DATA SHEET FOR PRESSURIZED PRODUCTS (Continued) PRODUCT TRADE NAME: Side 2 SECTION V - HEALTH HAZARD DATA THRESHOLD LIMIT VALUE (TLV)t ( )Not Applicable (T n ppm EFFECTS OF OVEREXPOSURE: EMERGENCY AND FIRST AID PROCEDURES: If unconscious, remove victim to fresh air and call a physician. If gotten in eyes, flush immediately with large amounts of water. (^Contains cardial sensitizer - if unconscious from inhalation, do not give adrenalin- type drugs, n SECTION VI - REACTIVITY DATA CHEMICAL STABILITY: ( )STABLE ( )UNSTABLE - CONDITIONS TO AVOID INCOMPATABILITY (Materials to avoid): ( )None with common materials ( ) HAZARDOUS DECOMPOSITION PRODUCTS (From burning, welding, oxidation, high temperatures): None ()Carbon Monoxide ( )Phosgene (^Hydrofluoric Acid ()Hydrochloric Acid £ HAZARDOUS POLYMERIZATION: (_JWill not occur (_)May Occur - Conditions to avoid: SECTION VII - LEAK AND DISPOSAL PROCEDURES STEPS TO BE TAKEN IF CONTAINERS ARE LEAKING OR LARGE AMOUNTS ARE RELEASED: (^JAvoid breathing vapors. ( )Remove ignition sources. (_~}Avoid skin contact with liquid. WASTE DISPOSAL METHOD: Do not puncture or incinerate containers. Give empty, leaking, or full containers to a disposal service equipped to safely handle and dispose of pressurized containers. SECTION VIII - SPECIAL PROTECTION INFORMATION RESPIRATORY PROTECTION (Specify type): (_)Not Applicable. (_J LOCAL EXHAUST (Hoods, Fans, etc.)»(_)Not Applicable. ID- VENTILATION MECHANICAL (General Area Ventilation): (_)Not Required ( )Should be on while spraying, to remove solvent vapor SPECIAL: QNot Applicable EYE PROTECTION: (_jNot Applicable ()Wear Goggles while spraying. PROTECTIVE GLOVES: ( )Not Applicable Wear:( )Rubber ( )Vinyl ()Polyethylene _Q gloves while spraying eg. P^B E»IF»Ti U»ot «MU»Me U» «t .»» ^^ ^ by w SECTION IX - SPECIAL PRECAUTIONS 1-3 PRECAUTIONS TO BE TAKEN IN HANDLING AND STORAGE: Do not store where temperatures could exceed D^°G (l30°F) Q °C ( °F). Q OTHER PRECAUTIONS: SPECIAL PRECAUTIONARY STATEMENTS: Please read and follow the directions on the product label| thsy are your best guide to using this product In the most sffeotlve way, and give the necessary safety precautions to protect your health. **Additional Notes or Comments from sections above: "late Filled Out: j Prepared or Approved by: The accuracy of data and information given on this form is not guaranteed, but it has been filled out to the best of our knowledge and belief. If you find any errors or have any suggestions to improve the presentation, please contact us at the address on the first sheet. •Table VII appearing on pages 265, 266 is a reproduction of the two sides of Form L751211A LCM, the Material Data Sheet for Pressurized Products
Aerosol Toxicology 267 Marketers are increasingly requiring the submission of OSHA-20 type forms from chemical suppliers, for individual components, and fillers, for total formulations. In addition, it is prudent to have a file of these forms available in case of chemically related plant accident, so that proper measures can be taken, even by relatively untrained personnel. The toxicological properties of a formulation are not normally the same as those predicted by taking a weighted average of the properties of the ingredients. For assurance they must be determined by testing the total formulation. The tests described under CPSC/FHSA and EPA/FIFRA have been mentioned. Similar tests are used under FDA and TSCA programs. In some cases, these procedures are over twenty years old and outdated. During 1980/1981 the Cosmetic, Toiletries and Fragrance Association (CTFA) Pharmacology and Toxicology Committee developed a series of nine safety testing guidelines for evaluation of various types of toxicity and irritation/sensitization. It is hoped that the regulatory procedures will be reevaluated and modified accordingly. These guidelines have now been published by the CTFA. Considering the acute tests described in the regulatory literature and mentioned earlier, the 1981 costs for having them performed at a typical outside laboratory are indicated in Table VIII. Other acute tests may be performed under special circumstances, such as a photosensitization study, vaginal irritancy test and teratology assay. They are not always relatively inexpensive; the teratology assay cost from $17,500 to $22,000 in 1981. Sub-acute Toxicity In toxicology the term "sub-acute" (or, sometimes, "sub-chronic") suggests a study of intermediate duration, where exposure lasts for a period of several days to a few months. A typical sub-acute inhalation or subacute feeding study would be conducted for 90 days. The objectives are to gain more specific information about the biological response to repeated exposures or multiple doses of a substance. These tests are used frequently to determine optimum protocols for chronic tests of still longer duration and greater expense. Although sub-acute tests almost never last more than six months, such a study would cover 25% of the average life span of the rat. Or it would be the equivalent of 202 months (17'years) in man. So, when done with certain animals, there are very definite chronic implica- / ( w = i - -- - - ^ / <- / / / / 1— H ~5~ < 0 -H , _ _ 1 1 ' z 9 V B r\ £ o S> n } w ~£ w « H < ? D s B W n ■i ^ *4 > 3 -" N ( - - - 1 da. 1 no. 1 yr. DURATION OF ADMINISTRATIVE PHASE OF TEST Figure 4. Toxicological Test Program Chart Arbitrary time-related divisions of toxicological testing program (approximate). dons. Despite the time-related standards developed by the World Health Organization (WHO) in 1966 where the acute, sub-acute or chronic definition was established with respect to duration administration, many toxicologists feel that the percentage of the life span of the test animal should be the controlling factor. The WHO standards are now very controversial, because of this and some other considerations. The term sub-chronic is used increasingly to describe tests where the administrative phase is from about 3 to 12 months duration. The WHO standard limits subacute studies to three months, and on the other hand, true chronic studies usually take from two years to the lifetime of the test animals. A comparison of the five time-related divisions of toxicological testing is given in Figure 4. Table VIII Fee Schedule (1981) for Acute Toxicology Studies (Average pricing) Acute Oral Toxicity Acute Inhalation Toxicity Acute Dermal Toxicity Primary Skin Irritancy* Primary Eye Irritancy* Dermal Sensitization Assay** Dose Range Finding Landsteiner Method 10 rats 10 rats 10 rabbits 6 rabbits 6 rabbits 4 guinea pigs 10 guinea pigs »190 600 600 260 260 250 1,200 *Draize Method. *Not normally performed unless a known strong sensitizer is present. Reference: Federal Register, CPSC 1500.3 Next Page
268 Previous Page Sub-acute Inhalation Unlike acute inhalation studies, which are aimed at establishing LC50 levels, and where post-exposure pathology is usually absent, sub-acute testing is designed to learn the effects of much longer exposures to specific, non-lethal concentrations of the substance in air. Typical exposure times are 10, 30 and 90 days, and 30 weeks. Observations made on live animals during the tests include body weight, electrocardiogram, x-ray, blood and urine chemistry and ophthalmologic examinations. Animals are sacrificed interimly during the longer tests, and also at the end of testing. Pathological and histiopathological routines are followed, skeletal measurements are made, and organ weights are taken. Out of this, a clinical picture is developed to show the resistance of the animal to the various concentrations tested. In one case of interest, studies at E.I. duPont de Nemours indicated that dimethyl ether (DME) had no effect upon rodents, except for a decrease in liver weight Figure 5. Human Respiratory System Cross section view of the human respiratory system. The Aerosol Handbook on exposure to 20,000 ppm for over 90 days but less than 210 days. All other acute and sub-acute tests showed excellent results. The company, under their product stewardship program, decided to sell the product but restrict its use to those applications where persons would not repeatedly inhale significant concentrations of the vapor. To implement this decision, they are now marketing DME for aerosol products, other than air fresheners and cosmetics. If the results of a two-year chronic inhalation program come in as anticipated, the restrictions will be removed. When an aerosol is sprayed into the air and some portion of the output is then inhaled, the lungs will come into contact with the gaseous component, as well as the portion of the spray particles having a diameter of between about 0.5 and 16.0 micrometers (f*m). Those particles that are below 0.5^m have properties much like cigarette smoke: they tend to "airflow" around much larger objects. When they are inhaled they remain airborne and are exhaled a second or two later. Particles with a mean diameter of 16.0^m or greater generally do not get much beyond the nose and nasal cavity immediately behind it. When they impact and penetrate to a lipid layer of the mucous lining in the nasal cavern, certain osmophoric ingredients may be picked up by the odor receptor nodes and transmitted to the brain as a particular smell. The 0.5 to 16.0^m range of particle diameters that can impact the lung must be regarded as an approximate one. The fact that we can physically smell true gases and also particles known to be smaller than 16.0fim proves that at least some of these components are impacted in the nasal vault. A number of colligative factors affect these approximate limits. Many aerosol particles are not roughly globular in form. They may contain solids or even be nearly 100% solid, with shapes ranging from approximately round, to platelike or even splintery. Some have little spiney solid accumulations on the surface, resulting from solvent evaporation. Others will have developed an intense electrical charge, either positive or negative. And a few, like fumed silicas, will have an exploded structure with a vast surface area but practically no density. All these factors tend to blur the limits of particle size for those aerosol droplets that can get into the lung and deposit there. Particles generally in the range of about 6.0 to 16.0^m can enter the lung, but have a high probability of deposition in the posterior nares (conchae) and vestibules that constitute the upper respiratory area. The
Aerosol Toxicology very uneven walls are covered with tiny hairlike ciliated columnar cells, generally protruding slightly from a mucous blanket. The cilia act like beating flaggella, causing the entire mucous layer to move upward at about 1cm/sec. Any deposited substances are thus carried slowly out of the upper lung area and into the throat, where they are swallowed or otherwise eliminated. A cross-sectional diagram of the lung is shown in Figure 5. Inhaled particles first enter the tracheal tube, which splits into two bronchii, one servicing the right lung and the other the left lung. The bronchii then divide into branches that carry any remaining particles into the five separate lobes of the lung system. At this point the cilial system becomes less dense and effective. Within the lobes the terminal bronchioles subdivide into respiratory bronchioles, a network of tiny tubulatures lined with alveoli or air exchange sacs. There are actually about 10,000,000 of these infinitesimal pouchlike structures, formed of reticular and elastic fibers that form a continuous network of supporting capillaries. It is within the alveoli that oxygen and carbon dioxide are exchanged. The total area of the human respiratory system may be compared with that of a football field. Less than a thousandth of this area is lined with ciliary cells. Once particles get past this ciliary area they may either be deposited in the deep lung recesses or else (if they are small enough) simply airflow back out again. Particles within the range of about 0.5 to 8.0/tm display the greatest ability to reach the respiratory bronchiole and alveoliar region and deposit there. Figure 6 shows the overall relationship of deposition fate to particle size. In general, the formulator should try to avoid the development of products that contain a very significant portion of the sprayed particles in the 0.5 to 10.0/tm area, on a weight basis. About 1975 this consideration became an important issue in the case of certain anti- perspirants that utilized zirconium/aluminum chloro- hydrate glycine complex as a superior astringent ingredient. Studies with the rhesus monkey showed that the inhalation of such products might cause irritation or lesions of the deeper lung tissues. The supplier of the so- called ZAGS complex modified his manufacturing method so that a new ' 'macrospherical-95 powder contained about 99.7% by weight of particles that were more or less round (roundels) and at least 6 /an mean diameter. The log/log stylized graph shown in Figure 7 269 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 AERODYNAMIC DIAMETER (microns) Figure 7. Aluminum Chlorhydrate Retention in the Lungs shows that only perhaps 0.04% by weight of typical Macrospherical-95F aluminum chlorohydrate complex will be retained in the deeper recesses of the lungs. Historically, this development did not prevent the FDA from acting "on the side of caution", and with essentially no persuasive data, to ban the further use of the ZAGS product in aerosols, regardless of particle size or even product use. (In fact, the ban extends to any and all zirconium compounds, and this has affected such diverse products as aerosol foams and lotions that contain zirconium hydrous oxide to help ameliorate the effects of poison ivy and poison oak exposures.) The controversy with respect to the use of ZAGS sensitized the FDA to the possibility that some respiratory hazard might be connected with the use of ACH in aerosol antiperspirants. Later they placed ACH in their over-the-counter (OTC) drug Category III, indicating PARTICLE SIZE (microns) Figure 6. Particles in the Respiratory Tract Deposition of airborne particles in the respiratory tract, shown as a function of aerodynamic dynameter. Data based on 15 respirations/minute and 750 ml tidal volume.
270 The Aerosol Handbook that further studies would be required in order to establish clinical safety. During January, 1982 the Cosmetics, Toiletries and Fragrances Association (CTFA) submitted a protocol for a two-year inhalation study on rats. Funding will be attempted if the FDA approves the design. Aerosol Vasodilators or Antiasthmatics Certain aerosol products are designed for delivery into the bronchiole/alveolar recesses of the lungs. While there are many different types and causes of the asthmatic state, the most common condition is that the terminal bronchioles (smooth muscle region) become constricted so that air can no longer pass freely down these passages to the alveoli. A frequent specific cause is a thickening of the mucous sheet. At any rate, the narrowing of the terminal bronchiole interferes with oxygen/carbon dioxide exchange in the alveoli sacs and results in labored breathing or even gasping for breath. Aerosol inhalants can relieve the muscle tone in the bronchioles and restore the normal exchange cycle. Aerosol inhalants are a very small part of the $11 billion pharmaceutical industry in the U.S.A.; nevertheless, they are important to aerosol people as the largest glass aerosol product and the largest product category still permitted to use CFC propellents. To the severe asthmatic, such products may be considered life-saving devices. In formulating this type of aerosol, the formula/valve combination should be selected as one that provides a maximum of particle weight in the useful 0.5 to 16.0/t diameter range. This maximizes bioavailability; in this case, that portion that reaches the smooth muscle area of the lung. It also minimizes impaction in the mouth or throat, which might bring on side effects such as the atrophy of certain enzymes that prevent Candida overgrowth. The ideal situation suggests that 95 to 98% of the particle weight should be below 10/«n with a peak particle size range of about 2 to 5/tm in mean diameter, with enough propellent still in the particle to give it a reasonably globular shape. Other considerations are that the toxicology of the adjuvants must be well established and the method of delivery of the drug must be such that the substance is delivered to the target area with high reliability and precision. Aerosol particles are deposited by several mechanisms: a. Impaction (Inertial Deposition) b. Sedimentation (Stokes' Law) c. Diffusion (Brownian Motion) d. Diffusiophoresis e. Thermophoresis f. Electric Mobility Important Minor Very minor over 0.5/tm Negligible over 0.5/tm Negligible over 0.5/tm Negligible over 1.0/tm The basic equation dealing with impaction is I = Ut U sin 0/gR, where Ut is the terminal settling velocity of the entrained particle, U is the velocity of the airstream, R is the radius of the airway and g is the gravity factor. For a non-turbulant system, the science of deposition by impaction is so exact that devices such as the Cascade Impactor utilize this technology to establish size brackets for aerosol sprays within the 1.0 to 50.0/tm range. Only modest advances have been made in the aerosol inhalant field during the past twenty years or so, but it is hoped that the future will bring some dramatic new items into the market. Insulin inhalant sprays are a possibility. Aspirin-type sprays have been seen in Europe, and their effect is very rapid. Mass immunizations by inhalation methods are a longer term possibility. Biological Consequences of Inhalation For the great preponderance of aerosols, the particle size distribution is such that either very little or practically none of the material will enter the deeper lung cavities. Even where this may occur, there are several removal mechanisms that generally serve to prevent accretion. They include enzymatic and absorbtion activities, plus several others. These relief mechanisms do not operate for some substances, however. For example, silica dusts that get into the alveolar sacs do not absorb significantly, cannot be dissolved, and cannot be digested by the phagocytes. Consequently, they accumulate, and over the years may eventually plug the sacs or otherwise act to decrease their transpirational efficacy. A number of substances are removed at a very slow rate. If mineral oils are inhaled, they can produce lymphoid pneumonia. Liquid paraffins of C12H26 and higher react similarly. Microdroplets of mineral oils produce an intense inflammation, and the small granulomas that develop contain fibroblasts and collo-
Aerosol Toxicology 271 gen as well as oil droplets. Thus recovery is slow and is often incomplete. In some cases, the shape of individual particles affects biological response. For example, the "soft" structure of highly porous exploded or fumed silica dusts invokes no profound changes, but if finely ground quartz (a micro-splintery form of silica) were to be used we would have a situation where a highly toxic reaction would occur. This material kills macrophages when ingested by them. Granulomas may develop at first but the material is released as the cells die and is taken up by more cells which die also; other toxic substances are released when the cells die and these may promote inflammation. The alveoli fill with masses of dead or immobilized macrophages and these stimulate the production of fibrous tissue by fibroblasts. The lesions due to extreme tissue reaction in simple silicosis may produce no early symptoms, even though the nodules are clearly demonstrated by X-ray. Severe respiratory disease may be caused by a chronic immunological reaction to inhaled particles. Allergic alveolitis is an acute inflammation of the lungs coupled with the development of chronic hypersensitivity granulomas. Such granulomas contain epithelioid cells (modified microphages) and inflammatory cells and tend to develop more rapidly than foreign body granulomas. The majority of materials causing allergic alveolitis are of vegetable and occasionally animal origin. A very high concentration of fungal spores must be present. The vast majority of people have no problem with inhalation associated with the normal use of aerosol products. Those with histories of asthma, hay fever or other respiratory difficulties have a statistically greater chance of developing adverse reactions. If coughing, difficulty in expelling air or other symptoms follow the use of aerosol sprays, doctors have suggested minimizing intake by holding the breath while spraying and then leaving the area, limiting the time exposure and spraying only in a well ventilated area. Heavy smokers should also minimize exposure as general rule. Hair sprays have seemed to be the major target category, where adverse inhalation responses are concerned. Over twenty years ago doctors coined the term "thesaurosis" to describe the nodules reportedly found in the lungs of a few people. Extensive tests were done by industry, using animals up to their maximum inhalation tolerance level (without contracting pneumonia), and also human volunteers subjected to extravagant dosages. The results were negative and the controversy subsided but never went away. It is rejuvenated from time to time as various medical reports come to the attention of the press. Several physicians specializing in pulmonary services suggest that strong adverse reactions to perfumes used in hair sprays can lead to serious consequences in highly susceptible people. However, the issue remains medically unproven. Hair sprays are among the most diversely formulated aerosol products known. For instance, the ethanol content varies from 15 to 80%, depending upon the cost of this ingredient, which varies widely from country to country as a result of both availability and taxation. Some countries effectively prohibit ethanol for this type of use, and isopropanol is used instead. Propellants Table IX Particle Size Distribution of Hair Sprays in Six Countries* Per Cent 10 pro 25 23 24 16 11 10 0.44 0.43 0.23 0.05 8.8 8.5 8.2 5.4 4.7 4.5 3.2 2.2 2.1 2.0 1.8 1.2 8.8 5.0 4.9 by Volume Under Size 20 /an 100 46 100 34 43 43 2.3 2.6 8.1 0.31 39 30 31 19 20 18 10 8.1 9.3 9.7 5.9 6.2 22 17 19 50 fim 100 84 100 73 99 99 19 25 100 3.2 99 89 92 71 80 77 42 39 51 59 27 44 73 60 55 "Belgium, U.S.A., France, Germany, U.K., Italy and the Netherlands, not presented in that order. Aerosols were equilibrated to about 75-7 7°F (24-25°C) prior to testing. The laser of a Malvern ST 1800 analyzer was positoned perpendicular to the axis of the spray cone at a distance of 16 " (40 cm). Duplicate results were averaged, except for F, where triplicate results were averaged.
272 The Aerosol Handbook have included CFCs, hydrocarbons, CO2 and various blends. All these factors have tended to bring about a wide range of particle size distributions, especially between countries. Some particle size data is provided in Table IX (Page 271). In the U.S.A., with the ban on CFCs that occurred in 1978, the propellent content of hair sprays dropped from an average of about 48% CFC/hydrocarbon blend to an average of 20% of hydrocarbons in the pressure range of 31 to 40 psig at 70°F (214 to 276 kPa at 21.1 °C), although one product now on the market uses a surprising 37.5% of hydrocarbons. It should have a much higher percentage of particles in the pulmonary deposition range of about 0.5 to 10.0/un diameter. Since about 1954 regulations under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), first administered by the U.S. Department of Agriculture (USDA) and later the U.S. Environmental Protection Agency (EPA) have divided pesticide sprays into three categories with respect to particle size distribution. The finest of these is the "aerosol space spray", where 80% or more of the individual spray particles have a mean diameter of 30/tm or less, and where none may have a mean diameter of more than 50/tm. Of intermediate size is the "pressurized spray", where (informally) 80% or more of the individual particles must be 50/tm or less. And finally, there is the "residual spray'', where none of the sprayed particles may be less than 50/im in mean diameter. Particle size measurements were made by the now- obsolete and very difficult Yeomans Method, which Table X Falling Rate, As a Function of Droplet Size (Stoke's Law) Time Required to Fall 1.00 Meter (3.281 feet) Diameter Qua) 0.1 0.5 1.0 5.0 10.0 20.0 40.0 50.0 100.0 200.0 Density - 0.8g/ml 48.0 da 1.9 da 11.5 hr 27.5 min 7.2 min 3.6 min 26.0 sec 16.5 sec 4.2 sec 1.1 sec Density - 1.2 g/ml 32.4 da 1.3 da 7.8 hr 18.3 min 4.7 min 2.3 min 17.5 sec 11.0 sec 2.8 sec 0.7 sec Note: A particle 0.1/tm in diameter has a volume of 5.2 x 10 16 ml and a particle of 10.0/im in diameter has a volume of 5.2 x 10"13 ml. Because of lateral wind currents the falling rate of particles below about 5/im in mean diameter may have little pragmatic meaning. involved spraying the aerosol towards a wax-coated glass microscope slide for a very brief period, then measuring the diameter of the micro-craters produced by the impact of individual particles containing solvent and P-l 1 components. After one or two hundred such measurements were taken, using a microscope with a reticulated scale, the diameter of the depressions was converted to the original diameter of the particle by a complex equation. The bottom of the range was at a depression diameter of about 0.0002 " (5/tm), corresponding to a particle diameter of approximately 2/tm. With the advent of modern laser-based aerosol particle size counters, such as the Malvern ST-1200 Analyser and the even more recent LAC 326, 16-channel Hiac/Royco Instruments Division analyser (Menlo Park, CA), which could now record vast numbers of particles in the submicron area (range 0.1 to 300/tm), the categorical definitions for pesticides have become antiquated and have fallen into disuse; that is, all except the generalization that "residual spray" products must have a particle size distribution lying above about 50/tm. Particle size categories are quite different in other countries. For example, in the Republic of South Africa the Department of Agriculture is now (1982) considering a proposal by the Aerosol Association that a pesticide "space spray" have at least 50w% of the particles under 50/tm and at least 95w% less than 100/tm, measured with a Malvern instrument at 20 " (50 cm). Similarly, a "surface spray" must have no more than 7.5w% of the particles smaller than 50/tm and no more than 20w% of the particles larger than 250/tm, measured at 12 "(30 cm). There are several reasons for this concern with particle size distribution. Certain relatively toxic insecticidal actives are permitted in "residual sprays", simply because the large particle sizes preempt them from entering into the pulmonary system of the body. The heavy particles fall to the floor quite rapidly, see Table X, and this effectively keeps them out of the nasal and tracheobronchial cavities. Several of these toxicants have recently been criticized (The Lancet, August 8, 1981, etc.), such as organophosphates, including mala- thion and dichlorvos (DDVP), and carbamates, such as propoxur ('Baygon'). Laboratory studies reportedly show that these insecticides and their derivatives can be mutagenic, hematoxic and leukemogenic when inhaled. Dichlorvos is permitted in "space sprays" in many countries, but generally with restrictions limiting
Aerosol Toxicology 273 use to 0.5 to 1.0% of the total formula. It is being increasingly scrutinized in relation to its biological effects. In the U.S.A. certain valve manufacturers have installed Malvern ST 1800 Analysers for the determination of particle size distributions and will provide this data to fillers or marketers who submit aerosols for such analyses. Particle size information may be presented in tabular form (see Table XXX - Propellent chapter) or in graphic layouts. The graph shown in Figure 8 relates to 100% full cans 1, 2 and 3 in Table XXX of the Propellent chapter. They each contain the same formulation: 15.0 % Toxicants in Odorless Mineral Spirits 17.0 % 1,1,1-Trichloroethane-inhibited 40.0 % Methylene Chloride - inhibited 28.0 % Propellent A70 Blend (Propane/isoButane) packed under identical conditions and with the same valve specification. The differences in particle size distribution are not detectable visually, yet Can No. 3 contains only 4.8% of total particle weight in the 0.5/on to 6.0/im pulmonary impaction range, where Can No. 1 contains 8.3% and Can No. 2 contains 8.9%. The difference is most probably due to very minor variations in valve geometry, which affect turbulent vaporization in the chamber, stem and actuator, and "flash-off efficiency": propellent separation just outside the terminal orifice of the button. The per cent by volume of aerosol particles under 10/ttn, and thus likely to impact in the pulmonary system, varies widely between products and even within product categories. For example, CFC/hydrocarbon type antiperspirants had from 0.85v% to 63v% in this range, according to a 1981 survey covering six countries in Europe. Similarly, a survey of 18 fly sprays showed that from 0.6v% to 58v% of the particles were in this range. Water-based air fresheners showed from 1. lv% to 10v%, and polishes showed 0.33v% to 2.7v%. Classical residual sprays such as starches, ironing aids, window cleaners and oven cleaners generally had no more than 0.2v% below 10/tm. Another survey showed that average single-application amounts of water-based air freshener, water-based flying insect killer (FIK), hair spray and antiperspirant Figure 8. Particle Size Distribution of Anhydrous Insecticide unit 1 full ION DM. • 22.31 unit 2 full MEAN DM.- 2133 unit 3<jli ML>H Di/.- 31.?1 PARTICLE SIZE ( m)
274 The Aerosol Handbook produced between 1.4 to 3.0 million particles in the 0.3-5.0/im range per square foot of floor area (0.093 m), and that the particles had a half-life ranging from 2.3 to 28.4 min. These levels compared with the smoke output from one cigarette in a large room: 6.9 million particles per square foot (0.093 in) and with a half-life of 30 sec, although here the particle size ranged from about 0.012/tm to 0.35/tm. Sub-acute Dermal (and Transcutaneous) Toxicity This is another area of rare involvement for the aerosol formulator. Where skin lotions or other dermally applied aerosol products are under development, the ingredients should be checked for compatibility by contacting the supplier. A typical test of this type would involve daily applications of the test substance to the pre-shaved dorsal skin area of the rat, with exposures lasting from 1 to 6 months. Dosages of about 500 mg per 20 cm of skin are about average. The skin is examined each day for edema, erythema and possible slough formation. If the time period extends to six months and the histologic appearance testing is elaborated by more sophisticated pharmacodynamic, mutagenic, teratogenic, reproductive, hematologic and other studies, then the program will have taken on chronic testing overtones. The results of these tests on raw materials should be reviewed carefully by the aerosol formulator, especially where any unusual substances are being considered. Chronic Toxicology. As indicated in Figure 4, chronic toxicological studies involve an exposure time of from about 3 months to the lifetime of the test animal, but most commonly, these durations are between 6 months to 24 months, with emphasis on the latter time period. They are designed to determine the effects of repeated or continuous exposure to a chemical. They are also used to determine if a compound is potentially carcinogenic (causes cancer), as well as to define a no-effect level. The objective is to actually find toxicity; to determine the harmful effects of a given substance. If such effects are not produced, the study will not have succeeded in a major objective, and it will not mean that the substance under test is nontoxic. As a consequence, some very high dosages may be administered, simply to produce the toxic effect within the time frame of the study. Only by this means can a safe dosage level be assessed with a reasonable margin of safety. There are special exceptions to this general rule in the areas of carcinogenic and teratogenic testing protocols. Standards of comparison are used often, where a new drug or other substance is screened against a reference standard that has been in the field for many years and is considered acceptably safe. Sub-acute Oral Toxicity This area is of relatively little interest to the aerosol industry, although such tests have been conducted with specific solvents and a few food aerosol formulations. A common technique is to administer about 1 to 2 g/kg/ day for about 15 weeks, using gavage or an intragastric tube. Animals are checked for food consumption, variations of body weight, activity and so forth. Pharmacodynamic studies may be made, such as determining effects upon metabolism and learning how rapidly the material may be excreted. At the end of the test about half the animals are sacrificed for pathological data; the rest are observed for any delayed changes, toxic effects or disturbances in progeny. Teratogenic Studies A teratogen is a compound that interferes with the normal development of the fetus (or baby). Technically, this is a one-time change and will not continue into the following generation. In the case of a mutagen, the change will appear in all the offspring produced thereafter. Although it has been recognized since 1945 that certain drugs and other substances may be teratogenic, still, the science did not really get underway until the thalidomide disaster, when an estimated 8,000 children were born deformed. There are at least eight known human teratogenic groups of agents. They include thalidomide, excessive Vitamin D, radiation, androgens, cytotoxic agents, rubella, cytomeglic virus and toxoplasmosis. Studies involve the use of chick embryos, the rat, mouse, rabbit and other animals. In a typical routine, the product is administered to the pregnant test animal by inhalation or oral dosing, during the critical mid-trimester period. For the rat this is from the 4th- 16th day of gestation; for the rabbit, from the 5th-20th day. The fetus is often delivered by Caesarean section, sacrificed and autop- sied, looking especially for abnormalities in the brain, eyes and gonads. The abnormalities are often very difficult to diagnose, especially tumors of the liver in rats
Aerosol Toxicology 275 and subcutaneous sarcoma (skin cancer) in the mouse and rat. A very large number of commercial and potential CFCs have been evaluated for possible teratogenic activity. P-113 showed partial or complete eye closure at 2%, during exposure only. P-21 showed no direct teratogenicity, but such effects may be implied from the fact that 60% of rats exposed to 1% of the vapor in air showed resorbtion of the early stage fetus by the body. P-22 may be weakly teratogenic in that there was evidence of a non dose-related 0.45% incidence of offspring with microphthalmia or anophthalmia in tests with 1,996 rats. P-133a caused resorbtion of about 60% of the fetuses at 0.2% and this was essentially 100% at over 0.5% levels. The hydrocarbon propellents have shown no indication of teratogenic behaviour. Methylene chloride was tested at 1,250 ppm with no indication of teratogenic, maternal, embryonal or fetal problems. Certain in vitro clinical tests may yield information that has teratogenic overtone significance. For instance, the in vitro cell transformation test, using rat embryo cells, showed that methylene chloride caused a 100% incidence of fibrosarcomas. Thus it was more potent than 1,1,1-trichloroethane - inhibited, or trichloro- ethylene. Such tests have screening merit only, and if positive results are encountered, more persuasive studies should then be conducted. Mutagenic Studies A mutagen is a substance which can cause a biological change to appear in the offspring and also in subsequent offspring. Many mutagens are also carcinogens and the two areas are closely related. A number of in vitro screening tests have been developed during the 1970s to provide a quick assessment of the mutagenicity/carcinogenicity of various substances. By far the most celebrated is the Ames test using bacteria. These assays provide results that range from about 40 to 80% of actual; in other words, they often indict compounds that have either no or an acceptably low mutagenic or carcinogenic potential when later tested against higher life forms. The Ames test, devised by Dr. Bruce Ames about 1972, uses Salmonella typhimurium, strains TA1535, Table XI Modified Ames Test Results Using Aerosol Grade Hydrocarbon Propellents Compound (Negative Control) (Positive Control) Methylene Chloride Propane n-Butane isoButane n-Pentane isoPentane Metabolic Activation* + + + + + + + III 2 2 50 50 50 50 50 50 10 10 10 10 Strain TA1538 10 30 16 52 14 16 18 37 7 16 8 22 14 16 Average Histidine Revertants Per Plate of S. Typhimurtium Strain TA98 29 38 234 237 18 21 22 48 26 26 22 18 15 22 Strain TA100 138 155 900 1066 144 88 122 134 108 98 138 116 124 124 *(-) Indicates that the metabolic activation system was not present. ( +) Indicates that the metabolic activation system was present. Only the highest dosage groups are shown in the interest of brevity. Only three strains of five tested are shown. The positive control (methylene chloride) was mutagenic in strains TA98 and TA100. None of the hydrocarbon propellents were mutagenic under the conditions of test; e.g. six hour exposure, followed by incubation for 42 additional hours before scoring. Reference: Kirwin, C.J. and Thomas, W.C.J.Soc.Cosmet.Chem. 31, 367-370 (1980)
276 The Aerosol Handbook TA1537, TA1538, TA98 and TA100, which are all histidine auxomorphs by virtue of mutations in the histidine operon. When these histidine-dependent cells are grown on a minimal media Petri dish containing a trace of histidine, only those cells that revert to histidine independence (his + ) are able to form colonies. The small amount of histidine allows all the plated bacteria to undergo a few subdivisions. In fact, this growth is generally essential in order for mutagenesis to occur. The his + revertants are determined readily as substantial colonies against the slight background growth of the histidine-dependent original forms. Within each of the Table XII Results of the Ames Screening Test For Mutagenicity, With Added Carcinogenicity Assays Substance Carbon Tetrachloride Vinyl Chloride Vinylidene Chloride Methylene Chloride P-11 P-12 Propane Butanes Pentanes Nitrous Oxide Folpet (Phaltan insecticide) Dieldrin (Insecticide) Chrysene (Polynuclear aromatic) Anthracene (Polynuclear aromatic) Mutagenicity 0 w + w + + * 0 0 0 0 0 0 + 0 + 0 Malathion (Dithiophosphate insecticide) - Thiourea Ethyl Carbamate (Urethane) Cyclohex'ane Acetone Acetic Acid Ethanol Isopropanol n-Butanol 0 0 0 0 0 0 0 0 EDTA (Ethylenediamine tetraacetic acid)0 DM SO (Dimethyl sulfoxide) Dimethylnitrosamine N-nitrosomorpholine N-nitrosopyrrolidone Guanidine Hydrazine Sulfate Hydroxylamine Hydrochloride Sodium Nitrite 0 w + w + w + + w + 0 w + Carcinogenicity + + + ? - 0 0 0 0 0 0 0 + w + cO 0 w + + + ? 0 0 0 0 0? 0 0 + + + + + 0 0 + =A positive result. 0 - A negative result, w + = A weakly positive result. 0? = Probably negative; more work needed. 'Positive with three mutant strains of Salmonella typhimurium, but shown to be negative via results of more elaborate tests and retrospective surveys. Most data from McCann, Choi, Yamasaki and Ames, Proc.Nat.Acad.Sci.USA 72 5135 (1975). strains the mutational frequency is relatively constant, but if a mutagen is added to the agar the frequency may be enhanced greatly. Another aspect of the test is the addition of a rat liver enzyme fraction to the agar in some plates, in order to simulate the ability of such enzymes in the liver, lung and kidney to metabolize various clinically inert chemicals to others, which may be carcinogens. If the mutation rate is enhanced on only those plates that contain the chemical plus the added enzyme (S-9 mix), then the chemical may be regarded as a co-mutagen, rather than as a direct-acting mutagen. During 1980 the hydrocarbon propellents were tested for mutagenic potential using the Ames test, with and without the metabolic activation system, and by exposing the Petri dishes to the highest concentration of vapors the bacteria could tolerate for six hours without lethal consequences. Methylene chloride, which normally gives a mutagenic result with two and sometimes three of the bacterial strains, was used as a positive control. The negative control was ordinary air. The abbreviated results of the test are shown in Table XI (Page 275). The Ames test, while it does yield indicative information has the defect that bacterial changes cannot be equated scientifically with the DNA changes in mammals that lead to mutations and cancer. Specific shortcomings are as follows: a. Bacterial cells have no nucleus; mammalian cells do. Bacterial DNA is in the general protoplasm. b. Bacterial DNA is bare, lacking the extensive protein coatings that envelop mammalian DNA. c. Bacterial DNA is a circular molecule; mammalian DNA is a long chain type. d. Mammalian DNA has many sites for the same gene, acting as a safety feature or spare parts mechanism. Bacterial DNA has almost none. e. DNA repair mechanisms differ between bacteria and mammals. f. Disturbances in bacterial membranes can seriously affect integrity and replication of their DNA, but in mammalian cells DNA is protected by protein coats. Methylene chloride is definitely mutagenic to the TA100 stran of Salmonella typhimurium on a linear dose response basis. It is about eight times as potent as 1,1,1-trichloroethane and trichloroethylene in this test. Yet is has been cleared of any mutagenicity or carcino-
Aerosol Toxicology 277 genicity on the basis of two-year studies using rats and hamsters. It does not bioaccumulate to any significant extent. A very large number of substances and mixtures have been subjected to the Ames screening test. The results obtained with some 32 substances which might be included in aerosol formulations are set forth in Table XII. Although the Ames test remains by far the most popular screening test for mutagenicity and carcinogenicity, due to cost factors, relative reliability of the results and so forth, at least six alternate studies are also fairly popular, and no less than 33 have been developed to date. The "second place" assay involves the ability of compounds to cause mutations in Drosophila melano- gaster, a species of the fruit fly, by a recessive lethal test technique. In the case of methylene chloride, some 14,600 insects were tested in this manner, with exposure for three days to a 0.1 % concentration of the solvent in their drinking water. No mutagenic activity was observed. One of the problems that has plagued methylene chloride is the mutagenicity/carcinogenicity of highly similar compounds. The retrospective human study that condemned vinyl chloride as a relatively potent carcinogen, causing a special type of liver cancer known as hemangiosarcoma, responsible for about 0.001% of all cancer deaths, also acted to indict other simple chlorinated hydrocarbons, merely on the basis of structural similarity. The theory was strengthened by the finding that 1,2-dihaloethanes have considerable mutagenic activity, as do X-CH2-Y geminal dihalocarbon compounds; see Table XIII. Perchloroethylene (CUCiCC^) was found to act as a carcinogen in rats and mice when administered by gav- age in the dosage range of 386 to 1072 mg/kg/day for 78 weeks. Dose unrelated hepatocellular carcinomas were observed in 40 to 60% of the mice, compared with a control level of about 10%. Results were inadequate to prove carcinogenicity in the rats on a conclusive basis, since many died during the study from dose-related toxic nephropathy and lung lesions indicative of pneumonia. Several studies involving the administration of chloroform (CHC13) have shown that this compound has significant carcinogenic activity. Vinyl chloride was used to some extent in aerosol hair sprays and a few other products until about 1965 when it was banned from such applications by the joint action of the EPA and FDA. Chloroform has been used in certain residual insecticides as a solvent, and perchloroethylene has been a component of a few pre-laun- dry cleaners and industrial products, again as a solvent. These uses have practically disappeared, at least in the U.S.A. and Canada. Carcinogenic Studies Carcinogenicity is so closely linked with mutagenicity that some aspects have already been covered above. In 1982 probably 1 to 4% of all cancer deaths may be due to past exposure to occupational chemicals, down from about 1 to 5% in 1978. The reason is that more safety measures were installed into workplaces about 1960 and later, as the science of cancer control developed. Cancer resulting from exposure in the U.S.A. workplace in 1982 is estimated as less than 0.5% of all cancer cases. This would indicate that the vast preponderance of cancers are caused by lifestyle factors. Many clinical scientists suggest that the present figure of some 370,000 cancers per year in the U.S.A. could be reduced by 50% by forsaking alcohol, cigarettes and meat products. (Meats contain dietary fat and sometimes nitrosamines.) There are several supporting pieces of evidence for such statements, such as epidemiological surveys of certain religious groups in the U.S.A. and various ethnic cultures abroad. Chemicals associated with cancer can be divided into three categories: direct carcinogens, procarcinogens, and promoters/inhibitors. Those in the first group will, by themselves, cause the malignant transformation of cells. They are nearly all highly electrophilic species and Table XIII Mutation Activity of Various Compounds on Drosophila Melanogaster (Fruit Flies) Compounds Control Methylene Chloride; CH2C12 Methylene Bromochloride; CH2BrCl Methylene Dibromide; CH2Br2 Dosage (mg/24 hrs) 0 5 to 10 100 5 to 10 100 5 to 10 100 Mutations (%)' 0.27 ±0.08 0.12±0.10 0.24 ±0.16 0.38 ±0.18 1.78 ±0.55 0.33 ±0.16 0.48 ±0.22 •Filipova, et al, Genetika 8 134-7 (1967).
278 The Aerosol Handbook include epoxides, certain solvents and even some anticancer drugs. The procarcinogens constitute the preponderance of important carcinogenic compounds. In their natural form they are not potent neoplastic agents, but can be metabolized and transformed by enzymes in cells to generate one or more strong carcinogens. The promoters/inhibitors constitute a large and ill-defined class. They do not cause neoplasms. But ethanol, various hormones, phorbol esters and other chemicals do act to promote and amplify the cancer-producing abilities of other compounds. Conversely, certain antioxidants, cellular molecules and vitamins are able to inhibit cancer by blocking the attack of carcinogens on sensitive DNA sites. Carcinogens create cancer by either directly damaging the DNA or by promoting or facilitating the manifestation of some inherent tendency toward malignant transformation. In 1982 at least, the theory of mutation by genetic damage is in favor. Regardless of the mechanism, the change results in a cell that has lost control of its growth cycle. It proliferates rapidly. The induced alteration is not lethal to the cell, but rather is perpetuated by its progeny. This is a neoplasm. The length of time between exposure and the appearance of a neoplasm can be surprisingly long. For vinyl chloride the period was between 14 to 29 years. Cigarette smokers may have 30 to 40 years of exposure before a tumor is manifest. And in the case of pregnant mothers who took diethylstibesterol, the cancers finally developed in their daughters. The evolution of a cancer is a slow, multistep process that requires decades to complete. The process is affected by age, hormonal status, competence of the immune and repair systems, rapidity of tissue growth and presence of promoters. The likelihood of tumor development following exposure to a carcinogen seems dependent upon total dose. These doses are additive; one big exposure or several small ones lead to the same end. If aerosols are implicated in the complex processes that may lead to cancers, the central concern must be the route of entry. Inhalation is the only one of importance. Solids, liquid particles and gases can all be inhaled. Solid particles that are about 8/im or less can be carried to the alveoli and absorbed in some cases. For filamentous particles, sizes up to 30-60/tm can reach the alveoli, as is evidenced in such conditions as asbestosis and talcosis. Mesothelioma is a cancer of the lung that is commonly equated with exposure to small- fiber materials, such as asbestos. Talc is a material used in certain aerosol products: some powder-type antiper- spirants and most after-bath perfumed body sprays, for instance. Because of the possibility of mesothelioma, only asbestos-free talcs should be used. Two such talcs are Whittaker, Clark and Daniels No. 1621 Italian talc and Alpine 123 talc, but there are others. (Incidentally, talcs that are chlorinated to kill bacteria and reduce iron content are sometimes capable of hanging on to residual chlorine that can harm the odor of aldehydic perfumes when formulated into aerosols. Simple heat-treated talcs are preferred.) Several marketers have elected not to use nitrite containing aerosol formulations, because nitrites may react with secondary amines to form N-nitrosamine carcinogens. Sodium nitrite is the main target, but n-propylammonium nitrite and other organic nitrites are also involved. West Germany is considering a ban on sodium nitrite, nitromethane and 1-nitropropane in aerosols, provided sufficient supportive data can be assembled by petitioners. Liquid materials that are used in aerosols and are suspected as being carcinogens include a number of important solvents. In 1982 the CPSC were still looking at methylene chloride and 1, 1, 1-trichloroethane, despite firm assurances from industry that exhaustive testing supported their continued use in aerosols. They were also concerned about xylene as a possible teratogen and carcinogen, perchloroethylene and formaldehyde. Cellosolve Solvent and dimethylformamide (DMF) are on their study list for review processing, but no action is planned in the near future. They have cleared hydrocarbon propellents of any possible chronic toxicity and probably will not take any action on chloro- carbons, even on a long term outlook basis. The Japanese report that triethanolamine (TEA) is a primary irritant and possible carcinogen checked routinely. During 1981 a report released by the National Academy of Science on "indoor pollutants" suggested that exposure to airborne chemicals is much greater in newer, more tightly constructed houses than in older houses or outdoors. The report centered upon carbon monoxide, radon gas, nitrosyl halides, formaldehyde and so forth, but chemicals originating from aerosol spray applications were also mentioned. Chronic studies are now underway at the National Laboratories at Oak Ridge, TN. Whatever these studies may show, the CPSC is just about through with responses that would result in bans. Their thrust would now be to reduce exposures to acceptable risk levels.
Aerosol Toxicology 279 Aerosol propellents available for general purpose uses in the U.S.A. have all been cleared of any possible carcinogenicity by means of a variety of testing programs. Newer propellent possibilities, not yet fully cleared as to carcinogenic potential, include P-22, P-142b and dimethylether(DME). P-22 gave a weakly positive Ames test, but a lifetime study on mice and rats showed no problems except for a minor incidence of salivary malignant tumors at 50,000 ppm exposures in the case of the oldest male rats. Final reports should become available in 1982, but the present conclusion is that P-22 is safe under TWA = 1000 ppm and reasonably anticipated consumer use conditions. P-142b has been subjected to a two-year chronic toxicity/carcinogenicity study at Bio-Dynamics, Inc. (East Millstone, NJ) with no adverse compound-related effects. Dominant lethal and cytogenic studies conducted during the first year of the overall study showed that P-142b was not mutagenic under the conditions of test. Complete results will be available about mid-1982 and should serve to permit unlimited applications of this propellent. In the case of dimethylether (DME), as reported earlier, a two-year study is in progress, and until the results are obtained and assessed (about 1983) du Pont has limited its uses to those involving minimal inhalation. It is not permitted for sale to those who might wish to use it in cosmetics or air fresheners, for example, under the company's product stewardship program. However, in Europe it is sold without restraint. The activities of government agencies have been mentioned throughout this chapter. They often arrange for long-term testing of chemicals by such groups as the National Cancer Institute (NCI), Battelle Memorial Research Institute \Columbus, OH), the National Institute of Safety and Health (NIOSH), and in the U.S. Department of Health and Human Services (DHHS). NIOSH periodically issues Current Intelligence Bulletins on various compounds covering their general toxicology or else their specific clinical behaviour in one or more areas. About six of their 38 bulletins (to early 1982) have dealt with chemicals important to aerosol formulators, such as formaldehyde. They are revised as new data is assessed. The EPA is active in controlling chemicals of possible toxicity t under FIFRA, TSCA, CAA and other Public Laws. Chemicals with both high exposure and high risk will be given priority consideration. An Interagency Testing Committee, composed of members from 21 government agencies and commissions, routinely makes recommendations to the EPA, and the EPA must then respond within one year as to whether it will require industry to conduct further tests. Late in 1981 the EPA proposed that industry test methylene chloride, 1, 1, 1-trichloroethane and nitrobenzene for health and environmental effects. All are being used in aerosols, although nitrobenzene uses are extremely limited. The TSCA mandate that a better system be developed for collection and retrieval of chemical information has resulted in the establishment of the Chemical Substances Information Network (CSIN). Planning is being done by about 25 government agencies with EPA playing a pivotal role. CSIN is designed to gather and sort many kinds of data, which includes the biological properties of substances, exposure data and any regulations that may apply. Government policies and regulations in the complex carcinogen area may be expected to become fully developed during the 1980s, as a result of unrelenting pressure from consumerist groups, plus an increasing reliance on improved short-term testing methods. Retrospective Epidemiological Toxicology Surveys The final step in the assessment of toxicity involves detailed studies of persons who have been exposed to a chemical under study, preferably for long periods of time. Many toxicologists consider this the ultimate and best test for toxicity. Animal tests have many shortcomings. An animal species, even primates, may not respond to a given chemical in the same way as humans. For instance, rodents develop more tumors when fed polyunsaturated fats as opposed to saturated fats. Humans have the opposite response. Many common substances, such as table salt, Vitamins A & D2, penicillin, estrogens, phenobarbitol, calcium compounds and saccharin are found to be either definite or suspected carcinogens in animal studies, although most are beneficial for humans, taken at realistic dosage levels. One large study has been helpful in establishing the safety of methylene chloride. It was carried out at the Eastman Kodak Company (Rochester, NY) about 1974. In some rooms used for film manufacture, the methylene chloride levels ranged from 30 to 125 ppm and peaked at 350 ppm. Some 750 white males worked in these rooms; about half for over 20 years, some for as high as 37 years. This was an important consideration
280 The Aerosol Handbook since some cancers have a latency period of 20 years, or even longer. For those persons still living, examinations showed no increase in cardiovascular, gastrointestinal (including liver), genitourinary, or central nervous system disease, compard with zero-exposure employees manufacturing film in the plant. Companion studies on people who had died, statistically showed that the causes of death for these people (comparing the figures with the expected number of deaths in various categories of disease for control persons) were actually less than the control group, and even less than that for the general population of the State of New York. The observed deaths from both malignant neoplasms (as cancer) and circulatory diseases were less than expected, based upon New York rates. Finally, the survivorship of the 20 + year employees was checked for some 13 additional years and was found to be better than that for Kodak Park, New York State and the United States as a whole. More scientific research is badly needed to better define how society can safely interact with the myriad of chemicals that are all about us and in our bodies. Essentially 100% of them are toxic and probably 10% are carcinogenic, in sufficient dosages. Like our skin, which constantly renews and repairs itself, our bodies can adapt to reasonable environmental conditions, using tolerance abilities that relate to gene redundancies, enzyme repair mechanisms, metabolic and physical elimination, cellular systems for resiliency and repair, and a host of other natural defense mechanisms — provided exposure levels are limited to reasonable amounts of toxic substances. The aerosol formulator must keep such concepts in mind, taking care not to expose people to relatively untested substances of unknown toxic potential, or conversely, only using those chemicals known to be safe under the gamut of reasonably forseeable conditions of use.
281 CRIMPING crimping is certainly one of the most critically important steps in the production of an aerosol package. A tight, dependable crimp effectively locks the formulation within the package, guaranteeing that it will not seep away at an excessive rate, thus creating a defective unit. Factual, definitive data on crimping is rather hard to come by. Perhaps the first such information was provided by the Crown Cork & Seal Company for their "Spra-tainer" cans about 1950. They listed two measurements, that of crimp diameter, suggesting 1.065 ±0.005" (27.05 ±0.13 mm); and crimp depth, recommending a specification of 0.242 "±0.005" (6.15 ±0.13 mm). This latter distance was measured from the top plane of the valve cup curl to the bottom of the 3/64" (0.047" or 1.19 mm radius) crimping collet. Because of the many controversies and complaints which arose as a result of these published specifications, Crown has probably wished, in retrospect, that they had been promulgated by some other source. Nevertheless, they have served a useful purpose and are still in use today, restricted to'' Spra-tainer'' applications, and with the crimp depth specifications revised to 0.195 ± 0.005 " (4.95 ± 0.13 mm) to reflect a measurement which can be used to check cans directly, rather than crimper settings. The distance now extends vertically from the plane of the valve cup curl to the center- line of the %4 " collet radius. As such, it differs by exactly one %4" collet radius, or 0.047" (1.19 mm), from the previous specification. The Crown "Spra-tainer'' figures remained the only published crimping data until about 1960 and 1961, when several articles appeared which provided similar data for three-piece tinplate cans. Compensations for the use of aluminum valve cups and unique can bead dimensions were also provided. During those days there were very significant differences between the 9
282 The Aerosol Handbook dimensions of three-piece can beads. Some canmakers supplied very tightly curled beads; others supplied relatively large ones. Different throat contours were used. Measuring methods for the thickness of the curl around the one-inch opening (G-Dimension) differed in both choice of contact point and angle of measurement. These and other factors delayed the establishment of firm crimping diameter and depth specifications for the most common of all aerosol containers. Meanwhile, similar difficulties were being encountered in the case of glass and plastic-coated glass aerosols. Variations in the finish dimensions of the glass, thickness of plastic coating, and thickness of valve gasket and housing flange all accrued to obstruct the determination of a useful crimping specification. Indeed, this complex matter was resolved by about 1968, after industry agreement on a formula approach, where the dimensions of the crimp were determined against those of the aerosol unit being considered. Aluminum cans and tubes present special problems, due to the large variation in bead contours (the smallest units do not even have a bead, as such), and the radial drawing grooves (eye lashes) which often cause leakage to occur. Even the bead dimensions of an individual can may sometimes show surprising latitudes. Much progress has been made on all these crimp- related problems during the past decade, and much more should logically be made in the near future as large committees of aerosol experts from both the CSMA and (in Europe) the FEA tackle the complex relationships involved in crimping valves to aerosol containers. Because of the diversity of special-situation crimping problems, and since the state of the art is such that many important questions still remain unresolved, no crimping specifications given in this book are to be construed as necessarily having official significance, or even the benefit of general industry agreement. They should not be used in the litigation of product liability cases. Valve manufacturers sometimes feel that the publication of crimping specifications might place them in an unfavorable position in such actions—particularly in the case of crimping maximums for the diameter measurement. General Considerations Recognizing the importance of the crimping operation (sometimes called clinching, hermetic sealing or swaging) most fillers pay special attention to this step. Dimensional attributes of the can bead, valve cup and gasketing compound are generally checked rather thoroughly. Crimp diameters, crimp depths, and sometimes torque resistances are taken at frequent intervals during the production run. The practice of hot-tanking is followed at nearly all aerosol plants. It is required by law for most metal containers, e.g. as certain heat- sensitive products may be exempted. However, it is not a requirement for glass and plastic aerosol units. Hot-tanking is a simple process, yet one which sometimes conveys a sense of false security. Only very high- rate leakers will be detected in the hot tank, as shown in Table I. The three minute time is that during which the container is completely submerged in a slow moving, full length hot-tank. Ten seconds is average checking time (waiting for an additional gas bubble or two) with the operator standing in one position, such as behind a vertical Plexiglas shield near the end of the tank. The 48 Table I Propellent Loss (Gas volume compared to weight loss of dispenser) Propellent Nitrogen Methylene Chloride* Propellent-12 Propellent-11 Propellent-114 Iso-butane Propane Carbon Dioxide** Weight Loss Per Year at70°F(21°C) 2.84 2.84 2.84 2.84 2.84 2.84 2.84 2.84 48 hours 13.6 4.6 3.3 2.9 2.3 6.55 8.94 8.94 Seepage Rate (ml at 70 °F (21 °C) 3 minutes 0.0142 0.0048 0.0034 0.0030 0.0024 0.0067 0.0091 0.0091 10 seconds 0.00079 0.00027 0.00018 0.00016 0.00013 0.00037 0.00051 0.00051 •Slightly soluble in 140°F hot-tank water. *'Significantly soluble in 140°F hot-tank water.
Crimping 283 hour readings refer to results in the CSMA Standard Seepage Rate Test. In the case of soluble gases, such as carbon dioxide, Propellent-152a, and so forth, a 25% brine solution could be used instead of water, but this is quite impractical except in a laboratory setting. Assuming that an alert operator could detect seepage at the rate of 0.02 ml per ten seconds in the hot tank, this still relates to extremely high annual weight losses; e.g. 150 g/yr. for isobutane and 300 g/yr. for Propel- lent-12. The solubility of carbon dioxide in heated water is such that hot tanking is almost valueless as a means of detecting low rate seepage losses of propellent. Finally, hot tanking cannot be used effectively to detect latent leakage problems, caused by changes in the shape, size or porosity of the flowed-in gasket, due to long-term actions of the product upon the elastomer. Particularly insidious are products which contain large amounts of gasket shrinking ingredients, such as etha- nol, with no compensating solvents which might exert a corrective swelling action. In spite of certain limitations, the hot tank remains a vital part of the aerosol filling operation. It detects extravagant leakers, defective cans and improperly made valves. It also provides an effective water flush to rinse product from the exterior of the can. Where a labeling job is required, warm cans will be found much more convenient to work with during the pick-up gluing operation. Three machines are utilized in can crimping operations, depending upon availability and the overall filling requirements: a. Standard Crimper i. Air-operated (noisy). ii. Electric motor operated via flexible shaft. (Rare.) iii. In-line type. Rated up to 70 cans per minute per head. iv. Rotary type. Normally three to six stations. b. Vacuum Crimper i. Requires high capacity vacuum pump as auxiliary equipment. ii. Rotary type. Normally three to six stations. c. "Under-the-Cap" Gasser by Kartridg Pak Company. i. Vacuum or atmospheric. ii. Rotary type; nine or eighteen head frames. d. Composite Filler/Crimper/Gasser Rotaries. Regardless of the machine used to make the crimp, it is necessary to feed the cans and adjust the device in such a way that the units will be essentially vertical at the time of crimping. Otherwise, depending upon the spring pressure, either a slanted crimp, or a "flat" crimp in a slanted can bead and valve will result. In the second instance, the downward spring pressure may be sufficient to drive the high part of the valve and can bead downward slighdy into the breast portion of the can dome. "TJnder-the-Cap" machines are normally supplied with 175-pound springs (more rarely, 310-pound springs for use with higher pressure propellents) and this is usually enough to depress the valve and can bead. Some distortion of the can bead itself may take place if the can is non-vertical during crimping, regardless of spring pressure. Gasket redistribution problems may result as a result of both uniform and non-uniform pressure applied during can crimping. This may or may not be beneficial, depending upon extent. A certain amount of controversy has arisen on the matter of spring pressures during crimping. Many experts feel that compressing the valve cup downward on the can bead immediately prior to crimping is undoubtedly helpful, but not vital in most instances. This is done on an exclusive basis in some laboratory crimpers. Aerosols containing only the concentrate can be crimped very effectively with no mechanical downward pressure. The crimping action itself generates Figure 1. Split Ring and Nut for Temporary Seal Assembly unit for temporarily sealing aerosol valves to one-inch (25mm) can bead. Assembly consists of a 3" (76mm) diameter knurled ring, split and hinged, with an inward flange at the base of the 1.238" (31.45 mm) hole to fit below the can bead, plus a knurled cap ring, threaded inside to fit the split ring. The split ring is positioned on the can dome and closed under the bead. A valve is placed in the ring. Then the cap ring is screwed down, sealing the valve to the can. This assembly allows valves and cans to be used repeatedly, and product changes to be compared, using the exact same valve each time.
284 The Aerosol Handbook Figure 2. Closed and Open Curl Configurations both a horizontal and downward force vector, with the latter being quite effective in snugging the valve down upon the can bead. For "problem" products, such as formulas which tend to shrink flowed-in gasketing compounds, and for "Sepro-can" products of all types, the downward spring pressure approach would be particularly recommended, plus the use of crimp depth dimensions that will help insure a tighter seal. The amount of spring pressure which should be used seems to be largely a matter of opinion and experience. Some years ago it was suggested that the range was normally between 55 lbs (25 kg) and 88 lbs (40 kg), with some manufacturers of crimpers setting about 74 lbs (33.6 kg) as an upper limit. The Alusuisse Metals, Inc. firm, which markets Boxal aluminum cans in the U.S.A. has recommended the use of a maximum down- Figures 3 and 4. lOx and 20x Magnifications of Open and Closed Curl Configurations
Crimping 285 ward pressure of 176 to 198 lbs (80 to 90 kg) for aluminum cans that contain only concentrate. In the case of Under-the-Cap (U-t-C) gassers, we have a special situation because the propellent is normally added to the cans just prior to the crimping stage. As a result, the head must be forced down upon the can valve with extra pressure to prevent a possible ' 'blow- by" event. A spring pressure pad with four "brown" springs is provided by Kartridg Pak as standard equipment. The springs are rated individually at compressions of 175 lbs/inch (3.13 kg/mm) and considering the various deflections used, are sufficient for all propellents except the highest pressure types, such as propane A-108 and CO2. For these gases a combination of diagonal "brown" and "blue" springs is recommended. A more complete discussion of this topic is found in the Aerosol Filling and Packaging Equipment chapter, under Kartridg Pak and Mace U-t-C machines. A practical approach to the determination of optimum spring pressure is that the can curl must not be deformed significantly during crimping and the Flowed-In® * gasket (if used) should be compressed by at least 0.005" (0.13 mm). Cut gaskets and the PE- sleeve gaskets are more uniform in thickness and are probably not compressed more than about 0.002 " (0.05 mm) as a result of normal crimping operations. Another area in which there has been substantial industry disagreement is the contour of the can bead, as it may affect the sealing integrity of the crimp. Since 1953 aerosol three-piece cans had been made with a so- called "closed curl"; that is, where the cut end of the can curl was tucked all the way underneath so that it contacted the can metal at the throat area, generally at about a 90° angle. But about 1965, when "Under-the- Cap" gassers came into widespread use, complaints about "phantom leakers" began to reach serious proportions. Actually, a fraction of a gram of propellent had been forced within the can curl during the gassing cycle, under about 600 psig (4.14 MPa) of liquistatic pressure, from which it afterwards escaped, either rapidly or slowly. The rate was dependent upon tightness of the metal-to-metal seal and other factors. Some of the "slower" cans entered the hot tank and gave signs of apparent leakage through the crimped seal. These were the' 'phantom leakers'', which were, in some instances, hard to distinguish from the true crimp leakers. Reacting to these complaints, the canmakers enlarged the plug diameter for domes going through the •® A registered trademark of the W.R. Grace Corporation. punch press, causing the formation of so-called "open curl" tops, where the cut end was perhaps 0.02 " from the metal at the throat section. With this alteration, ' 'phantom leakers'' ceased to be a problem. For crimping purposes, however, it seemed that this new bead contour was less satisfactory since it could be deformed more easily. When the crimp is effected, the metal of the valve cup wall is pressed tighdy against the metal at the can throat. This is essential if the valve is to be wrapped sufficiendy under the can curl so that the crimp is tight. In most cases mere is a very slight outward movement of the throat section, due to the crimping force. With a "closed curl", where an essentially 90° angle exists at the cut edge and mroat junction, the can bead itself is also pushed upward and out slightly during crimping. This exerts an extra compressive action upon the flowed-in gasket, resulting in a tighter fit without undue metallic distortion. This advantage does not apply to the "open curl", which is not normally contacted during crimping. At this point, it should be noted that if a "closed curl'' can is made wimout the approximately 90° angulation, so that the cut edge of the can bead can slip upward along the throat metal during crimping, or if the crimping operation is sufficiendy out of control so that excessive mroat distortion will cause such cut edge slippage even with good angulation, then a much greater potential problem may ensue. By slipping upwards, the can bead is rendered smaller in diameter, sometimes by as much as 20% in the "G" dimension, and the compressive seal of the flowed-in compound is abrogated. Unless the formula exerts a swelling action on the compound, such units are very likely to become latent leakers. This type of leaker appears to have a satisfactory seal for several weeks or months, after which a relatively high level of seepage commences. For curl comparisons see Figures 2,3, and 4. In practice, conversion to the "open curl" appeared to bring about a serious leakage problem at several plants which specialized in filling hair sprays. Three factors seemed to be involved whenever such crimp leakage was noted: a. Use of "open curl" cans. b. Storage of finished units in the inverted position. c. Use of an U-t-C Propellent Reclaim unit during production. Inverted storage had been used as a cure for problems caused by concentrate entrapment in the dip tubes
286 The Aerosol Handbook Figure 5. Dimensions Surrounding Crimped Can Curl Used in the Calculation of Crimp Settings as a result of container evacuation prior to gassing in the U-t-C. It is now thought that the "open curl" is able to deform downward to a certain extent under the combination of the downward force vector resulting from crimping, plus the downward pressure applied by the four springs in the U-t-C. When the spring compression force is removed after crimping, the valve cup can then recover and spring back slightly, more so than the shorter radius arm can bead. This has a loosening effect upon the flowed-in gasket. The absence of any reinforcing from the cut edge part of the bead would have a similar slight loosening effect upon the throat wall. These two effects would then act in concert to make the gasket more accessible to the product, particularly in cases where the can was stored inverted. It is known that, after several weeks of such inverted storage, some hair spray formulations (principally the P-l 1 or methylene chloride ingredients) can extract enough material from GK-45 gasketing compound so that it will become relatively porous, causing leakers to appear. Sub-committee "C" of the Aerosol Division Commercial Standards Committee, CSMA, was formed around 1969 to investigate this and related problems and continues to be very active. Thus far, the hair spray situation has not been completely explained, particularly the involvement of the reclaim units, unless this was fortuitous, as some now think. By changing to GK-70 as the gasketing material, it appears that the problem can be avoided completely, since this elas- tomeric blend is more resistant to extractions than GK-45. However, it is somewhat more expensive, said to cost about $1.50/M more, as a part of finished valves. In 1977, when CFC propellents were replaced with hydrocarbon types, the problem vanished altogether. The aerosol filler exercises control of the crimp during the crimping operation by adjustments in crimp diameter and crimp depth. Various changes in the dimensions of other critical factors can often be compensated by altering the crimp settings. Correspondingly, crimp specifications which can be used to cover a particular production run can be calculated from a knowledge of the dimensions of the other critical factors. It is necessary to measure each of the component dimensions, checking a sufficient number of parts for each one so that the actual dimensions and tolerances can be established with reasonable precision. A knowledge of the relationship of these factors is also useful as a means of determining the cause of crimping problems. The interrelationship between crimp diameter and crimp depth can be scaled out geometrically or calculated trigonometrically from Figure No. 2, devised by Roy Rousseau of the Kartridg Pak Company. As a crimp diameter decreases, so must the crimp depth (on a lesser scale) in order to maintain the same degree of crimp tightness. This is found to be a change of 0.002 " in crimp depth for a change of 0.005 " in crimp diameter. The variation is direct, over a reasonable range of typical values. Crimping Specifications for Metal Cans The CSMA Crimp Committee (Subcommittee C) has not yet developed any recommendations on what specifications should be adopted for crimping. Actually, the committee takes the view that it would be unwise and perhaps impossible to recommend a standard crimping practice until basic standards are first developed on how crimp should be measured. Sample lots of containers have been shipped to laboratories of about ten companies participating in the crimp study to see if reproducible results can be obtained by these laboratories in measuring crimp, and to determine how closely the results obtained by any one laboratory will match those obtained by others. Different gauges, such as the Federal Tool Company and Kile Machine Shop crimp diameter and crimp depth gauges are currently
Crimping 287 being compared for reproduceability and accuracy by Sub-committee C. The variations have been considerably larger than anticipated. Participating laboratories have also been asked to report on what procedures they follow in measuring crimp. Some companies take a gauge reading on every segment of the crimp—others measure at a single point. A few measure between segments, but most firms measure from the middle of each segment. The committee plans to urge all in the industry to follow a standard procedure in measuring crimp, taking a reading for depth and diameter in the middle of each segment. Only after they have standardized procedure in measuring crimp, and been able to demonstrate that different laboratories can obtain reproducible results, will they be in position to approach the eventual goal of developing basic standards for crimping. Some years ago the committee devised and approved a listing of sixteen critical mechanical considerations which affect the crimp. Roy Rousseau has assigned specifications and other conditions to these dimensions, based upon geometrical and mathematical analysis. The individual dimensions are taken from accepted manufacturing standards. The data presented in Table II (Page 286) illustrate this relationship. Similar relationships can be established to show the way in which a number of other critical dimensions affect optimal crimp depth. The following five dimensions are now considered: a. Gasket material thickness. b. Collet foot thickness. c. Tinplate thickness of valve cup. d. Can curl thickness, (G-Dimension). e. Diameter of the can opening. When the crimp diameter is fixed at 1.070 ", a crimp depth setting of 0.185 " is used when these five dimensions are all at their midpoints or targets. The individual effect of each of these critical dimensions upon These dimensions are provided in the CSMA "Aerosol Guide' Seventh Eauion, (1981) as "Industry Specifications for Tin Plate Fabricated Aerosol Cans". Critical Dimensions of the Can 1. Diameter of can opening 1.000 ±0.004" 2. Can Curl Thickness: 0.130 ± 0.007 " Critical Dimensions of the Valve Cup These dimensions may be considered as ' 'Proposed Tentative Standard Dimensions" provided through the CSMA. They apply only to tinplate valve cups. 3. Outside Cup Diameter: Bv 4. Inside Skirt Radius: Ry-Tv 5. Tinplate Thickness: Tv 0.011 ±0.001" 6. Flowed-In Gasket Thickness (Dry) Dv 0.023 ±0.010" 7. Flowed-In Gasket Length: Ev Critical Dimensions of the Crimping Collet Applies only to 6-segment, 3/W radius collets designed for standard one-inch valves. 8. Collet Foot Radius: 0.047 ±0.002" 9. Check Diametral Integrity of Collet in Expanded Positon. (Ring Gauge) 10. Check Corner Radius at Each Edge of all Segments. (Radius Gauge) Critical Dimensions of Crimped Valve Cup These dimensions apply only to one-inch tinplate valve cups, crimped onto tinplate cans. 11. Measure Crimp Diameters Across All Segment Impressions: 1.070 ± 0.005 " 12. Measure Crimp Diameters Across all Segment Gaps:* 13. Measure Gap Width Between Sections of Crimped Impressions:* 14. Check for Contact Between Can Curl and Valve Cup at Segment Impression:* Check for Contact Between Can Curl and Valve Cup at Gaps Between Segment Impressions: * 15. Measure Crimp Depth at Each Collet: 0.185 ± (Variable) 16. Measure Mounting Cup Gasket Compression at Top of Can Curl, after Crimping:* a. Measure gasket thickness before crimping. b. Measure distance between top of can curl and inside surface of metal valve cup. *Industry specifications not developed as of 1982.
288 The Aerosol Handbook Table II Crimp Depth vs. Crimp Diameter Settings Crimp Diameter 1.065" 1.068" 1.070" 1.072" 1.075" Crimp Depth 0.183" 0.184" 0.185" 0.186" 0.187" Table III Crimp Depth vs. Gasket Material Thickness Gasket Thickness (I n-crimped.) Gasket Thickness (Crimped) Crimp Depth Value Ah Valu< 0.013" T9" ..j23" 0.027" 0.033" 0.007" 0.010" 0.012" 0.014" 0.017" 0.180" 0.183" 0.185" 0.187" 0.190" —0.005 —0.002 0.000 0.002 0.005 Table IV Crimp Depth vs. Collet Radius Collet Radius 0.045" 0.047" 0.049" Crimp Depth Thickness of Valve Cup 0.010" 0.011" 0.012" Crimp Depth 0.183" 0.185" 0.187" Table V vs. Valve Cup Crimp Depth 0.1844" 0.185" 0.1856" Ah —0.002" 0.000" 0.002" Thickness Ah —0.0006" 0.000" 0.0006" Table VI Crimp Depth vs. Can Curl Thickness Can Curl Thickness Crimp Depth Ah 0.123" 0.127" 0.130" 0.133" 0.137" 0.178" 0.182" 0.185" 0.188" 0.192" -0.007' -0.003' 0.000' 0.003' 0.007' adjustment of the crimp depth can be elucidated from the "Delta h" values in the five tables which follow. The total adjustment of crimp depth thus becomes 0.185 " ± the sum of these five "Delta h'' values. Gasket Material Thickness The thickness of the flowed-in gasket material had earlier been specified as 0.022 ± 0.007 ". The origin of this specification appears uncertain, but it is now regarded as too tight for gaskets made under ordinary methods of production and control. A more reasonable specification is 0.023 ±0.010". In the preparation of a crimp of proper tightness, the gasket is ideally compressed to about 50% of the initial thickness, or to a final specification of 0.012 ±0.005". A change in the final thickness of the gasket will require a correspondingly large change in the crimp depth setting. A variation in the thickness of an uncrimped gasket will necessitate a half-sized change in the crimp depth. These ideas are illustrated in Table III. Collet Foot Thickness Both V32" (0.031" or 0.79 mm radius) and %<" (0.047 "or 1.19 mm radius) crimping collets are available, but the V32" size is less reliable and is being phased out in favor of the %4 " collet. These discussions consider only the 764 " collet size, which has a foot radius specification of 0.047 " ± 0.002" (1.19 ± 0.05 mm). A change in this radius affects crimp tightness by a direct relationship, as shown in Table IV. Thickness of Tinplate Valve Cup Tinplate valve cups are nearly always produced from 100# plate, which has an average thickness of about 0.011" (0.28 mm). Variations are usually within ± 4% for a given lot of valve cups, but may extend to as high as ±10% for different lots. A change in metal thickness of the valve cup requires a corresponding change of about 0.6 the amount in crimp depth, to maintain the same crimp tightness. This relationship is shown in Table V. An increase of 0.001" (0.025 mm) increase in crimp depth, due to the vertical vector introduced at the crown of the cup, plus a decrease of 0.0004 " (0.01 mm) due to the vertical vector of the thickness at the point of hard contact. The net result is an increase of 0.0006 " (0.015 mm). For all practical purposes the effect of plate thickness on crimp depth can be neglected, unless the cup is
Crimping 289 made from aluminum alloy, in which case the effect is significant because the cup is much thicker. Can Curl Thickness (or "G" Dimension—CSMA) Can curl thickness is a measurement taken at an arbitrary angle of 20° from the horizontal, using a special micrometer. The barrel type micrometer was developed by the Commercial Standards Committee of the Aerosol Division of CSMA, and has since been slightly modified by the manufacturer. The can curl thickness measurement carries a specification of 0.130 ±0.007"(3.30 ±0.18mm), as applied to cans made in the U.S.A. and Canada. The dimension relates, in a generalized way, to the effect of the can bead in the establishment of correct crimp depth. A change in curl thickness requires an equal change in crimp depth, as seen in Table VI. Since the can curl thickness may be determined accurately and rapidly, and since it exerts a greater effect upon the establishment of proper crimp depth than any of the other critical factors, the measurement should be taken from at least three points around the can curl, and the results averaged. The can curl thickness measurement should not be confused with a similar measurement: that of contact height, which is used widely in Europe. The normal range of contact heights for U.S.A. tinplate cans can be given as 0.163 ±0.007", (4.15 ±0.19 mm), as determined by the BAMA or Kroplin (S-2002) "ball-and- anvil" gauges, or the Boxal gauge, which is of die "drum-and-anvil" type. If one of these gauges is available (the BAMA and Boxal cost about $600 each, but the unofficial Kroplin gauge costs only about $180), it may be used to determine the height of the can bead as it directly affects the crimp depth; e.g. Table VII. Diameter of the Can Opening A variation in the diameter of the can opening affects the tightness of the crimp in an inverse fashion. If the assumption is made that an increase in the minimum diameter of the opening, normally 1.000 ± 0.004" (25.4 ±0.1 mm), will relate to an equal increase in the diameter at the point of hard contact, usually about 1.028 ± 0.004 "(26.1 ±0.1 mm), then, if the contour of the can throat at the point of contact is at an angle of about 36° to 54°, increasing the radius of the can opening by 0.001" (0.025 mm) will require a decrease in the crimp depth of 0.001" (0.025 mm) in order to maintain tightness. The relation to the can opening diameter, then, is an inverse 1:2 ratio, as shown in Table VIII: Table VII Crimp Depth vs. Bead Contact Height Can Bead Contact Height Crimp Depth Ah 0.155" 0.159" 0.162" 0.165" 0.169" 0.178" 0.182" 0.185" 0.188" 0.192" —0.007" —0.003" 0.000" 0.003" 0.007" Table VIII Crimp Depth vs. Can Opening Diameter Diameter of the Can Opening Crimp Depth Ah 0.996" 0.998" 1.000" 1.002" 1.004" 0.187" 0.186" 0.185" 0.184" 0.183" 0.002" 0.001" 0.000" —0.001" —0.002" Figure 6. Device to Measure Throat Radius of the Can Dome [II o Assembled and separated views of a device engineered by the American Can Company and produced by the Paramount Machine & Tool Corp., Fairfield, NJ, to determine the throat radius of the can dome. The three small circles at right in the picture below are gauge standards.
290 The Aerosol Handbook Figure 7. Upper Portion of 211-Diameter Can Where the can contour at the point of hard contact is between about 30° to 36° with the horizontal plane, the ratio between crimp depth and can opening diameter becomes about an inverse 2:5 relation. A more precise ratio can be derived trigonometrically for any particular contour, but such refinements are rarely necessary. Figure 9. BAMA Gauge Figure 8. Can Dome and Upper Body of Aerosol Upper portion of aerosol can is encapsulated in clear amber plastic and cross-sectioned. After polishing the cut surface, exact measurements can be taken at critical areas. The technique is used to measure key dimensions without allowing can areas to warp or deform due to cutting. Sealing efficiency, potential strength can be studied. Device developed by the British Aerosol Manufacturers Association to determine "point of hard contact" for various can domes. Gauge setting standard ring is illustrated at side. Table IX Variation of Crimp Depth as a Function of Dimensions of Six Factors Critical Factor DeKchption of Crimp Ideal Crimp 1.070" 0.000" 0.012" 0.000" 0.047" 0.000" 0.011" 0.000" 0.130" 0.000" 1.000" 0.000" 0.185" 0.000" Typical Crimp 1.068" -0.001" 0.015" t 0.003" 0.047" 0.000" 0.011" 0.000" 0.127" —0.003" 1.002" —0.001" 0.183 —0.002" Abnormal Situation 1.075" + 0.002" 0.017" + 0.005" 0.049" + 0.002" 0.012" + 0.0006" 0.137" + 0.007" 0.996" + 0.002" 0.2036" +0.0186"" Crimp Diameter Measurement Difference from Ideal (Ah)* Casket Material Thickness Measurement Difference from Ideal (Ah) Collet Foot Thickness Measurement Difference from Ideal (Ah) Tinplate Thickness of Cup Measurement Difference from Ideal (Ah) Can Curl Thickness Measurement Difference from Ideal (Ah) Diameter of Can Opening Measurement Difference from Ideal (Ah) Crimp Depth Measurement Difference from Ideal Depth •Represents amount of crimp depth adjustment necessary for compensation *Sum of maximum positive crimp depth adjustments, as given in Tables II, HI, IV, V, VI, and VIII
Crimping Calculation of Crimp Depth Having described the six critical factors which influence crimp depm, it is now possible to illustrate meir quantitative effects by citing three examples: an ideal situation, a typical situation and a highly unlikely situation, where each factor acts to increase the required depth. This is shown in Table IX. From this development it might appear that the crimp depth should be specified as 0.185 ±0.019" (4.70+0.48 mm), in the event that the six critical dimensions which affect the depth dimension are all at the positive limits (or the negative limits) of their individual specifications. However, these circumstances have an occurrence probability of less than a million to one. Note: For practical purposes the crimp depth may be specified as 0.185 ±0.005" (4.70 ±0.13 mm), unless some particular deviation in the other critical dimensions is noted, making it desirable to change the midpoint of the crimp depth specification accordingly. Note 2: Assuming the tolerances represent normal 2-sigma values (95.46% confidence levels), the chance for all six to be at their maxima or minima at the same time is calculated as one in 1.142 x 10e. If no preliminary study of the six critical dimensions which affect crimp depth is undertaken, then the tolerance for the crimp depth must be derived from the theorem that the standard deviation of the sum of any number of independent variables is the square root of the sum of the squares of the standard deviations of the independent variables. In the present instance: Independent Variable Crimp Diameter Gasket Material Thickness Collet Foot Thickness Tinplate Cup Thickness Can Curl Thickness Diameter of Can Opening X' 1.070 0.012 0.047 0.011 0.130 1.000 2rr* 0.002 0.005 0.002 0.0006 0.007 0.002 o~' 0.001 0.0025 0.001 0.0003 0.0035 0.001 So that: 't/c'cDi*2 * K""GMT>2 ♦ <°"CFT>2 * <°"TCT>2 * <°"cCT>2 + <°" DCO>2 =~\/<0.001)2 + (0.002S)2 + (0.001)2 + <0.0003)2 + (0.003S)2 + (0.00I)2 »", CD 21.59 x 10-" 3 Valve Cup 1.2 mm Radius (0.047") Figure 10. Point of Hard Contact mm (1.067") Diameter * 'CD = 4-646 " 10' 2o- 'CD = 0.0093 Contact Height of the Can Bead As mentioned previously, the concept of contact height was developed in Europe, where it has been widely used since about 1969. Contact height may be defined as the vertical distance from the top plane of me can bead to the centerline of a measuring ball (of radius equal to the thickness of the proposed valve cup, plus the radius of the proposed clinching collet toe) when the ball is positioned so as to touch the can throat profile at the "Point of Hard Contact". See Figure 10. The "Point of Hard Contact" in turn, is an exact position, horizontally around the can throat, which represents the uppermost point of contact between can and valve cup, during normal clinching. It is also the highest point at which the valve cup is still under direct control of the clinching collet. To measure this point, a hardened steel ball of about 0.059 "(1.50 mm) radius is positioned within the can so that it touches the wall lightly at this exact location, and the measurement is taken in terms of contact height, as described above. The vertical centerline through the ball will be found (trigonometrically or mathematically) to be about 0.0135" (0.34 mm) inward from the radius of the can curl—or about 0.4865 "(12.36 mm) from the centerline of the can. This offset distance is dependent upon the can having a normal mroat profile, the valve cup having a normal diameter of 0.992 ±0.004" (25.20 ±0.10 mm), and on other factors as shown by the formula: From this treatment it can be seen that the 2-sigma specification for crimp depth, as an average figure plus deviations for the six critical dimensional factors, will be 0.185 ±0.009 "(4.70 ±0.23 mm). This specification can be narrowed to the more usual one of 0.185 ±0.005 "(4.70 ±0.13 mm) only if it is first ascertained that high-influence factors such as compressed gasket thickness and can curl thickness are pre-checked and found to be within tighter limits than their normal specifications would indicate. This is often the case on individual lots. R + t- (S + 2t —D) (FEA Standard 401 E; indicating derivation) ; or alternately, by the simplified formula:
292 The Aerosol Handbook Contact Height Variable Measured by Means of Dial Gauge Measuring Anvil 1.5 ran (0.059 ' Radius .55 mm (.014") Constant Built — into instrument Figure 11. Gauge to Measure Contact Height in which: R = t = S = D = Radius of the clinching tool — normally 0.047 " (1.2 mm) in the U.S.A. and Europe. Plate thickness of the valve cup — normally 0.010" (0.25 mm) in the U.S.A. and 0.012 " (0.30 mm) in Europe; allowing a 0.001" (0.025 mm) reduction during drawing. Diameter across expanded clinching collet — normally 1.070" (27.18 mm) in the U.S.A. and 1.067" (27.10 mm) in Europe. Internal diameter of the can opening — normally 1.000" (25.4 mm) in the U.S.A. and Europe. The value for "X", (0.0135 " or 0.014" in Europe), can be calculated for U.S.A. cans and clinching specifications as: X =0,Q47"- (1-070-1.000") 2 X =0.012" (or 0.305 mm) The value for the diameter of the hardened ball "RB ", (0.059" in Europe), can also be calculated for U.S.A. cans as: RB =R+t RB =0.047"+0.010" RB =0.057" (or 1.45 mm) These deviations from the European situation are small, but even then, since the U.S.A. ball (0.002" smaller in radius) is brought 0.0015 " (0.033 mm) closer to the can wall, the original situation is restored almost exactly. Typical specifications for contact height are provided in Table X. At least for U. S. A. tinplate cans, a direct relationship appears to exist between crimp depth and contact height: Crimp Depth = Contact Height ± t + Gc, in which t = Plate thickness of the valve cup — normally 0.010" (0.25 mm) for tinplate and 0.015 " (0.38 mm) for aluminum, allowing for a reduction of 0.001" (0.025 mm) during drawing. Gc = Flowed-in gasket thickness after crimping — normally 0.012 " (0.30 mm). Thus, for tinplate: Crimp Depth =0.163" +0.010" +0.012" Crimp Depth =0.185" (or 4.70 mm) For aluminum: Crimp Depth =0.171" +0.015" +0.012" Crimp Depth =0.198" (or 5.03 mm) These results match generally accepted figures for crimp depths in the United States, provided the crimp diameter is targeted at 1.070" (27.18 mm). Since curl thickness (CSMA "G" Dimension) is taken at an arbitrary 20° angle, there is no direct relationship between it and contact height. The contact height circle appears to be about 0.014" (0.36 mm) higher on the can throat than the curl thickness circle, in the case of tinplate cans. A similar relation exists with aluminum cans, except for J.L. Clark Manufacturing Company tubes where the throat profile will not permit a 20° measurement, so the company proposes one made at about 10°. The BAMA (British Aerosol Manufacturers Association) gauge is the most favored one for measurements of contact height. It is available from British Indicators, Ltd., Acrewood Way, Hatfield Road, St. Albans, Hertfordshire, England, at a cost of about $600. The Boxal gauge is fairly popular in France and may be purchased from Boxal France, S. A., 38 Beaure- paire, France. The principle is similar to that of the BAMA gauge. The main difference in construction is that a ' 'barrel'' or' 'drum'' with a vertical axis replaces the ball. The Kroplin S-2002 gauge is best known, although unofficial. It operates on the ball principle.
Crimping 293 Flowed-In Gaskets A highly es.sential element in the job of sealing the valve into the container is the mounting cup gasket. Its major function is to serve as an effective sealant for the valve into the clinched seam. This is accomplished in two ways. The primary seal is provided by the shoulder portion of the film of gasketing material. The thicker, channel portion of the film provides a necessary secondary seal, thereby insuring sealing latitude to the filler. It also serves as a cushioning device during the crimping operation. This is of particular importance when containers are being gassed and crimped on automatic machines such as Under-the-Cap fillers. The material from which the flowed-in gasket is compounded must have physical properties so that initial sealing will be provided against gas leakage, and the gasket must also resist product attack and gas transmission during the shelf life of the product. Because of the wide range of products packaged as aerosols, and the variety of propellents used, the development of satisfactory gasketing materials has presented quite a problem. Early in the development of aerosol containers, the need for a valve mounting cup gasket which would seal effectively yet would remain in the cup through valve assembly and filling operations was met by the Flowed- In® Gasket. In 1952, the Dewey and Almy Chemical Division of W.R. Grace & Co. introduced a peptized, vulcanizable dispersion of chloroprene rubbers (neo- prene) which could be applied in a "flowed-in" operation. The compound, properly cured, provides a rubbery, highly resistant gasketing material. Now, thirty years later, the aerosol industry still uses a modification of that original compound, as Darex® GK-45 NVH. Other early attempts to provide a sealing system considered alternate approaches such as a natural latex gasketing system, Darex Cap 48, some of which is still used, but only on a special order basis. A modification of that formulation, called Darex Cap Compound 1564 was developed in England for the European market, since raw materials for the GK-45 formulations were not available in Europe. The 1564 Compound provided a thicker, somewhat softer film, which proved suitable for the sealing conditions encountered in the European market. Today it is an important compound used to seal aerosol valve mounting caps in Europe. In a given country, compound selection involves a combination of factors, not the least of which is the gasket's ability to perform under a specific set of conditions. Which material is used depends on the domestic availability of raw materials for manufacture, the sealing requirements of the local aerosol industry, the types of cans used, and the methods for filling them. For example, GK-45 NVH is used in many of the major Table X Contact Height Specifications for Various Cans and Valve Cups Continent No. America No. America No. America Europe Europe Europe Can , Material E.T.P. E.T.P. Aluminum E.T.P. E.T.P. Aluminum Valve Material E.T.P. Aluminum Aluminum E.T.P. Aluminum Aluminum Valve Wall Thickness 0.009" to 0.011" 0.015" to 0.017" 0.015" to 0.017" 0.012" to 0.016" 0.020" to 0.024" 0.020" to 0.024" Contact Height Knglish I'nits 0.1634 i 0.006'"' 0.1634 i 0.008"" 0.1712 t 0.008"" (No data) 0.1575 ± 0.006"* 0.1653 ± 0.006"* 0.1673 ± 0.006"* Specifications Metric Units 4.15 ± 0.15* 4.15 ± 0.20" 4.35 ± 0.20" (No data) 4.00 ± 0.15* 4.20 ±0.15* 4.25 ± 0.15* 'Figures supplied by F.E.A. (Italians, suggest 4.25 ± 0.15mm) ""Figures supplied by Editor from tests.
294 The Aerosol Handbook GAGING COMPONENT SPECIFICATIONS A B C 0 E F BASE INDICATOR BALL DIA WEIGHT VALVE CUP PLATFORM DIAL INDICATOR TOTAL WEIGHT OF BALL AND MECHANISM FEDERAL PRODUCTS OR EQUIVALENT 093 DIA GRAMS 3 POINT SUPPORT EQUALLY SPACED 001 - 1.000 RANGE WITHOUT SPRING 55-60 GRAMS Figure 12. Gasket Thickness Gauge Diagram of Thickness Gauge for 1-inch valve cup flowed-in gasket. SET-UP: 1. Check that ball indicator point is screwed tightly into indicator stem. 2. Ball point must rest on one of the three valve cup platform supports. 3. Remove gasket from one of the lot of valve cups to be measured. 4. Place the stripped valve cup on the platform, and with ball indicator resting in gasket groove rotate the dial to point zero. 5. Remove valve cup from platform and proceed to measure valve cups. PROCEDURE: 1. Raise indicator stem and place valve cup on platform, release indicator gently and record thickness shown on dial indicator. (This will be thickness of the gasket only). 2. Raise indicator stem, rojate valve cup approximately 90 degrees, release indicator down gently, and record second reading. 3. Rotate cup 90 degrees two additional times, proceeding as in step 2; record readings #3 and #4. 4. Record average of the four readings, plus the high and low reading of each cup measured. Available from Alpha Gage & Machine Tool Co., Downers Grove, IL. aerosol markets, but only to a vanishing small extent in Europe. It seals effectively the entire range of aerosol products packaged, and performs extremely well in Under-the-Cap filling. In the European market, there is still a great deal of curl dimension and profile variation among countries and among different types of containers. The natural rubber latex compounds, Darex Cap 1564 and 1586, used in Europe, provide a thick, soft gasket which will seal over this wide range of curl configurations. While 1564 Compound is used successfully in many Under- the-Cap filling operations, it does not typically exhibit the wide latitude that GK-45 NVH demonstrates in these applications. Improvements are being made to the 1564 type of compound to improve its performance in Under-the-Cap filling. The relative cost of these compounds will vary from country to country. For example, the Darex GK-45 NVH series compounds would probably be more expensive than Darex Cap 1564 in Europe. Conversely, in the U.S.A. the reverse is true. Cost is primarily a function of the availability of raw materials and the manufacturing equipment located in that country, but may also be affected by tariffs and trade agreements, if the material is not manufactured in that country. To review the chronology of the currently-used sealants in the U.S.A., the original GK-45 compound was introduced in 1946. It consisted of a solvent solution of peptized, vulcanizable special neoprene rubbers which upon drying and curing formed the final gasket. The first major improvement in this type of compound was Darex-45 NV which eliminated the necessity for vacuum stirring before application and greatly reduced the incidence of gasket pinholes. A higher total solids version offering certain application advantages, Darex GK-45 NVH, was developed subsequent to the GK-45 NV version and is now the standard Flowed-In® gasket type in the U.S.A. In response to an industry need for a sealing material with more latitude for ethanol-containing products which tend to shrink GK-45 series compounds, Darex GK-70 was developed. This material, which swells in the presence of alcohol or pure propellents, increases the margin of sealing latitude available to the filler. It is now only rarely needed, and available only on special order. Most commonly used gasket thickness specifications call for a .025" ±.007", or .022"±.010" for ® Registered trademarks of the W.R. Grace & Company.
Crimping 295 GK-45 NVH. Allowable side-to-side variation (high to low) may be from .005 " to .015 " depending upon the requirements of the individual user. Standard quality control procedures should ascertain film thickness and variation and insure that the compound film is continuous, without voids which might develop into leakage paths. It is also important that the gasketing system be fully cured to develop its best resistance properties. A color cure chart, which gives a visual indication of cure, is available from the Dewey & Almay Division for most compounds. Years of field experience and compound testing indicate that the major factor in obtaining a good seal is a good clinching operation. The gasketing material functions as sealing insurance to allow for variations in package components and process, as well as to provide abuse resistance in handling and distribution. The sealing compound's latitude allows the filler to operate an efficient high-speed operation with the equipment and personnel conditions common to the industry. It is the consensus among industry experts that most field leakage complaints are a function of less than satisfactory clinching practices. For a one inch tinplate mounting cup with a GK-45 NVH gasket, a clinch depth of .185 ±.005" and a diameter of 1.070 ±.005" are considered to be best. Crimping practices may vary somewhat from filler to Figure 13. Photo of Device to Measure Gasket Thickness within the Arch of the Aerosol Valve Cup. Cups are positioned on three studs. Platform is rotated to obtain three or more readings per valve cup. The device was developed by the Aerosol Division, CSMA. filler due to special situations. It is not yet clear as to whether there is a real difference in clinch formation or perhaps a difference in technique and methods of measuring clinches. Investigatory work is still being conducted in this area. In summary, the Flowed-In Gasket system provides the aerosol package with efficient, field proven, sealing insurance. A substantial and complementary discussion of valve cup gaskets is provided in the Aerosol Valve chapter Table XI Properties of Flowed-In Gasketing Compounds Compound Total Solids Specific Gravity (Dry Film) T>|M- Com pound Film Weight Commercial Cycle Range (WET) Casket Gauge Milligrams Range DAREX GK-45 NV 56-58% 1.45 Chloroprene Rubber Solvent Solution I hour air dry 1 hour @ 155° F 1 hour <» 200° F 1 hour C"> 325° F 505-545 .018 "-.03 2" DAREX GK-45 NVH 60-62% 1.45 Chloroprene Rubber Solvent Solution 1 hour air dry lhour<S 155° F 1 hour <» 200° F 1 hour @ 325° F 470-510 .018"-.032" DAREX GK-45 W DAREX GK-70 DAREX CAP 1564 60.5-62.5% 45-47% 84-87% 1.50 Chloroprene Rubber Solvent Solution 1.51 Chloroprene Rubber Solvent Solution 2.50 Natural Latex Dispersion "lhour air dry 1 hour @155° F 1 hour <? 250° F 1 hour <? 325° F * 1 hour air dry 1 hour @ 155° F 1 hour @ 250° F 1 hour @ 325° F 2 hours @ 165° F 485-525 .018"-.032" 595-635 .015"-.029" 750-800 .030"**
296 The Aerosol Handbook and should also be consulted. This material also includes in-depth descriptions of cut gaskets, which are the most widely used form in Europe and enjoy significant use in the U.S.A. [especially for aluminum cans with one-inch (25.4 mm) openings], as well as the Precision Valve Corporation PE-sleeve gasket, first used commercially in 1981. The PE-sleeve gasket is probably the most important single development in the valve gasket area in thirty years and should capture a large share of the worldwide aerosol market during the 1980s. In order to accommodate the 0.012 to 0.014 "(0.31 to 0.36 mm) thick sleeve on the side wall of the valve mounting cup and still have it fit within the 1.000 ±0.004" (25.4 ±0.1 mm) can or plastic bottle openings, the cup has been modified to have a side wall i.d. of 0.944 ±0.003" (23.97 ±0.07 mm), and o.d. of 0.964 ± 0.003 " (24.49 ± 0.07 mm). Production experience has shown that new or fairly new 6-segment crimping collets often have difficulty in entering these smaller diameter valve cups. They may not come back out, once forced in for the crimping operation, and this causes "hang-ups" in the crimper or U-t-C gasser. Depending upon the degree of wear, the 6-segment collet will cause various degrees of vertical scoring or scratching on the inside wall of the valve cup — often right down to the steel itself. A new 6-segment collet will have a fully compressed minimum average diameter of 0.946 " (24.03 mm) and is generally slightly larger. The six segments do not come together in a true circle, but as a sextet of arcs representing the original diameter of the bar stock used to make the collet, which is variously 1.060 " to 1.070 "(26.92 to 27.18 mm), depending upon the manufacturer. As a consequence, the diameters Table XII Influence of Crimp Cap Height Upon Valve Cup Gasket Leakage Rate Formula: 5% Isopropanol, 65% Methylene Chloride and 30% Hydrocarbons A-46 Valve: PVC, with 0.020" stem, 0.080" body, 75A Durometer Viton stem gasket, dimpled cup, Latex WDH cup gasket Crimp Diameters: 1.076 to 1.080" as noted Crimp Depths: 0.173 to 0.177" Temperature: Ambient Can No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Crimp Diameter Range 1.077- 1.078" 1.077- 1.078" 1.077- 1.079" 1.076- 1.078" 1.077 - 1.079" 1.077- 1.078" 1.077- 1.078" 1.077- 1.078" 1.076- 1.079" 1.077- 1.078" 1.077- 1.078" 1.077- 1.078" 1.077- 1.079" 1.078- 1.079" 1.078- 1.079" 1.078- 1.080" 1.077- 1.079" 1.078- 1.080" 1.077- 1.080" 1.078- 1.080" 1.078- 1.080" 1.078- 1.080" 1.078- 1.079" 1.078- 1.080" Sum of 1 to 4 0.011" 0.012" 0.014" 0.014" 0.012" 0.015" 0.012" 0.014" 0.012" 0.012" 0.013" 0.012" 0.014" 0.013" 0.013" 0.012" 0.013" 0.012" 0.013" 0.012" 0.012" 0.012" 0.011" 0.012" Opposing Crimp Gap Heights* 2 to 5 0.013" 0.013" 0.012" 0.012" 0.012" 0.013" 0.014" 0.012" 0.014" 0.017" 0.012" 0.013" 0.012" 0.012" 0.012" 0.016" 0.013" 0.014" 0.013" 0.011" 0.014" 0.018" 0.013" 0.018" 3 to 6 0.011" 0.014" 0.013" 0.014" 0.014" 0.013" 0.011" 0.014" 0.017" 0.013" 0.012" 0.014" 0.012" 0.012" 0.012" 0.017" 0.014" 0.012" 0.012" 0.015" 0.012" 0.012" 0.013" 0.012" One Low Prediction 2.75 4.05 3.63 3.95 3.34 2.53 210.50x 266.81x 11.82x 61.33x Year Weight Loss at 100°F Medium Prediction 5.95 6.07 6.29 5.99 3.79x 7.24 10.18 13.18 254.72x 312.78x 310.73x High Prediction 9.68x 32.58 311.70 'Average of adjacent crimp diameters less gap diameter. Note: individual opposing gap heights may be considerably different; e.g. they are not necessarily one half the sum of opposing gap heights. xPrediction was incorrect, based on gap height sums (9/24 or 37.5% wrong.) Cans 12, 14, 18, 20 and 22 showed partial gasket outward extrusion.
Crimping 297 across the splits in the fully closed segments are about 0.004" (0.1 mm) larger than the average, or about 0.950 " (24.12 mm). Since this diameter is equal to the average i.d. of the valve cup it is not hard to visualize how a below average i.d. cup would be "hung-up", badly scratched or possibly distorted by 6-segment collets. As an example of collet-making, one major manufacturer uses a 0.060" (1.52 mm) wide grinding disc to slice the formed bar stock into the six desired segments. As the abrasive disc wears, one can expect that the kerf of these slices would drift down to something below 0.060" (1.52 mm), and this would have the effect of making the fully compressed diameter of the sextet of segments somewhat larger. For instance, if the grinding kerf became an average of 0.057 " (1.45 mm) due to wear on the discs, the fully compressed diameter would increase by the same 0.003 " (0.08 mm) difference. This would then act to exaggerate the problem. It would, of course, be possible to use grinding discs of greater thickness to cut the collet segments from the original shaped bar stock. Using a 0.070" (1.78 mm) grinding disc on 1.060 " (26.92 mm) diameter bar stock would give a 6-segment collet with a fully compressed minimum average diameter of 0.927" (23.55 mm) across the toes, which would resolve the problem of crimping the PE-sleeve type cup. However, when the collet is spread to a typical 1.070 " (27.18 mm) to effect the crimp, the segments will then be separated or gapped to an excessive 0.075 " (1.90 mm) and gap leakage (often related to latent leakage) will be invited. A study of gap height (which is a function of gap length — the greater the length the greater the height) Figure 14. Kile Crimp Diameter Gauge The Kile Machine Shop aerosol crimp diameter gauge, shown with a slotted turret accessory for increasing accuracy, and particularly for the determination of gap diameters between crimping indentations. Figure 15. Eight Segment Crimping Collet Initial diameter of uncut bar across collet toe's is 1.060", shown as segments 3 and 4. The fully compressed (minimum average) diameter is 0.943", shown as segments 1 and 2. Typical crimping (average diameter is 1.070", shown as segments 5 and 6 (Range ± 0.001"). The maximum crimping (average) diameter is 1.075", shown as segments 7 and 8 (Range ± 0.001") has been made on the basis of a one-year weight loss assessment. The results are reported in Table XII. Data was obtained with the crimp diameter gauge and holder shown in Figure 14. The predictions of leakage rate, as low, medium or high, were 62.5% accurate, which is probably significant statistically, considering that an average height of opposing gaps was used (not the true individual gap heights), and that a number of other factors influenced weight loss. During 1980 it occurred to Franklin D. Haase of the Peterson/Puritan, Inc. research staff that, if an 8-seg- ment collet were to be used the kerf of the dividing cuts could be much less than for the 6-segment collets and still allow the fully compressed collet toes to slip within the PE-sleeve type valve cup. About the largest 8-seg- ment collet that will still work easily with the PE-sleeve valve cup is illustrated in Figure 15. When the segments are opened to produce a 1.070 " (27.18 mm) crimp—measured across the center area of each opposing crimping indentation—the collet gap is then only 0.050 " (1.27 mm), which is substantially less than that of any 6-segment collet. Haase arranged for the preparation of some 8-segment collets, meeting the
298 The Aerosol Handbook dimensions indicated in Figure 15, and found that they were able to apply an excellent, scratch-free crimp on PE-sleeve valve cups. In addition, weight loss studies using both high-alcohol and high methylene chloride formulations showed conclusively that average weight losses were reduced, probably because of the significantly reduced gap length and gap height. Production tests later showed that this particular design had an average life-span of only about 200,000 Figure 16. Device to Measure Valve Cup Inside Diameter and Fully Closed Diameter of Crimping Collets The tool is machined to initially include the dotted portion at the bottom. This area is turned to an i.d. of 0.960 * for a vertical distance of 0.100 * in order to establish a base point for the 1:50 taper. Taper dimensions are: A = 0.900" B = 0.959* C = 0.960" The bottom 0.147" portion is cut off after the taper is produced in order to facilitate closed diameter measurements for 3/64" radius crimping collets. To measure the closed diameter, insert the collet firmly into gauge. Measure protruding length. Subtract from total length to obtain the inserted length "Y". Calculate closed diameter from the expression: CD. = 0.960" -0.020Y Closed collets should have maximum diameters of 0.942" for PE- sleeve type mounting cups and 0.965" for regular Flowed-ln or cut- gasket mounting cups. The 0.941" "go/no-go" gauge at the top is designed for incoming inspection of PE-sleeve type valve mounting cups, which should have an inside diameter of 0.944 ±0.003". If the gauge end goes into the cup quite easily the cup is satisfactory. If it enters with any difficulty or friction, then the cup i.d. is too small or out of round. crimps, whereas the average 6-segment collet averages about 550,000 crimps, when used for a variety of products. (Some products, such as starches, shorten the life of a collet considerably, whereas non-aqueous solution type products enhance collet life. Collet cleanliness is also important.) In response to the short life-span problem, Haase then set about designing a greatly improved segment profile. By switching to a different alloy he was able to both harden and case harden the new collets to about the Brinnell 64 level, making them substantially more wear resistant than the average collet. The new Mark V 8-segment collets are currently (1982) passing the 850,000 crimp level in a production setting, with a variety of products, and none has broken or shown any appreciable sign of wear. A series of Mark IV 10-segment crimping collets have also been prepared and these are performing satisfactorily as well, on production lines running a variety of products. In this case, the gap length and gap height are reduced still further. The evaluation of any benefits from additional weight loss reduction will have to await the results of tests now in progress. As a part of the research program relating to the crimping of PE-sleeve valve cups and the development of 8 and 10 segment collets of a superior design, Frank Haase also devised a testing device (a) to check PE- sleeve type cups for acceptably large inside diameters on a go/no-go basis and (b) to determine the maximum circumscribing diameter of the fully closed collet across the collet toe area. The device is illustrated in Figure 16. Not all well-worn 6-segment collets will work with the PE-sleeve for crimping purposes; many still scratch the inner cup wall and leave the exposed steel free to discolor or corrode. Not all 8-segment collets work either, for that matter. Collets of this type have been sold by the Mace Engineering Company (California) and at least two other firms for a number of years, and none of these particular designs appear to work in production with the PE-sleeve cups. By using the gauge in Figure 16 one can predict whether a particular lot of PE-sleeve valve cups will work in production with a specific group of crimping collets. Causes of Container Leakage at the Crimp The largest single cause for defective crimped seals is the use of an incorrect setting for crimp depth. It is necessary to consider this dimension rather carefully, and in context with the six critical factors which influence it. Special circumstances, such as the use of alumi-
Crimping 299 num valve cups, aluminum cans, pre-formed gaskets, PE sleeves, unusual aerosol compositions and so forth may also have to be considered. The CSMA, FEA, and some can suppliers are against the publication of any specific figure for crimp depth, since so many factors significantly influence this dimension. The usual aluminum can with inward or outward curl will seal at a typical 1.069 " (27.15 mm) diameter and 0.193 " (4.90 mm) depth (Boxal specification for flowed-in gaskets). Aluminum cans with solid beads (certain two-piece varieties) are rarely encountered in the U.S.A., but they require a depth of about 0.202 ±0.006" (5.13 ±0.15 mm) for a good seal. The use of extra-thick or double-thick flowed-in gaskets can pose substantial problems unless the crimp depth is let out by some 0.006 " to 0.012 " in compensation. The relative novice may use the normal crimp depth figure of 0.185 " with little or no appreciation of the many related factors. Generally the figure will give a good crimp, but there are enough instances where it will not, so that industry associations and suppliers naturally hesitate to propose what may be looked upon as a hard figure; one mat will always provide a good crimp. Crimp diameter is usually specified as 1.070 ± 0.005 "(27.18 ±0.13 mm) in the United States. In Europe crimp diameter is specified by die FEA as 1.067 ( +0.008/-0.004") of 27.1 the metric equivalent 27.1 +0.2/-0.1) mm. The range of 1.063" to 1.075" matches very closely the most recent U.S.A. range of 1.065" to 1.075". These specifications apply only to three-piece tinplate aerosol cans, fitted with tinplate valve cups. Since an aluminum valve cup is about 0.005 " (0.13 mm) thicker than a tinplate cup, at least in the U. S. A., compensation must be made for this fact in the settings of both crimp depth and crimp diameter. The depth should be deepened, as previously described. The diameter could be specified as 1.060 ±0.005", but is usually set for a litde more than this to compensate for spring-back effect. Aluminum valve cup alloys are more subject to cracking than tinplate, and hot tank leakers are sometimes seen where the gas bubbles emerge from metal splits at the end of one or more crimp indentations. Procter & Gamble and other firms have made an intensive study of this problem, and as a result, specifications are now available for suitably rounding the edges of the crimping collet toe so that split leakage is minimized, while still retaining a good hermetic seal. Aluminum tubes and cans are more difficult to crimp satisfactorily than are those of tinplate construction. The can curl is almost always more variable in terms of contact height, planarity and metal smoothness. Some containers have radial grooves resulting from the forming operations running across the crown of the curl area. This condition can be detected better by running the fingernail very lighdy along the crown than by direct visual scrutiny or other methods. Crown grooves will sponsor crimp leakage with flowed-in gaskets unless the seal is made very tightly. The use of cut gaskets improves seal reliability. Extra thick flowed-in gaskets can be supplied by some cup manufacturers, which also improve crimping integrity. A study on die optimum crimping of 1.375" and 1.500" diameter aluminum tubes has shown that U.S.A. aluminum valve cups are best sealed using a crimp diameter of about 1.091" and a crimp depth of about 0.164 ". The work was performed on "Peerasol'' tubes, and is not necessarily relatable to tubes made by other manufacturers. Glass aerosols are generally more difficult to crimp than metal cans, one reason being that there is more variation in the shape of glass containers than mere is in metal cans; thus it has not been possible to set up as tight specifications for glass botdes as for cans. Crimping has been a particularly severe problem on plastic coated glass aerosols. 1.231 « 0. 008" Figure 17. Shoulder Profile of Aluminum Can
300 The Aerosol Handbook One of the reasons why crimping of glass aerosols has continued to be a problem is because testing glass aerosols for crimp has itself been a problem. Grip test, torque test, study of crimp profile — none of these test methods has been satisfactory for glass. Thus Ed Budzilek of Wheaton Aerosols Company has suggested (Aerosol Age, Apr. 1967, pg. 40) that the same method used in checking crimp on metal cans be applied, with modifications, to glass aerosols — using a crimp height and crimp diameter measurement. But, instead of establishing a single specification for heights and diameters, he suggests establishing separate measurements for each combination of valve and container from different suppliers. His suggested system, and a formula to be used in its application, are described in the article in Aerosol Age referred to above. Modern crimping machinery can usually apply crimps at depth and diameter tolerances of ± 0.005 " ( ±0.13 mm). With close attention, diameters can be held to ± 0.002 " ( ± 0.05 mm) for the three diameters (1-4, 2-5 and 3-6) on an individual can, and to about ± 0.0035 " ( ± 0.09 mm) for cans and valves out of single lots. Crimp depths can rarely be held much better than ±0.003" (±0.08 mm) for the six indentation depths on a single can (or the eight indentation depths on single cans clinched with eight segment collets). For cans and valves within the same lot, ±0.005" ( ±0.13 mm) is a minimum tolerance. The "Under-the-Cap" gassers made by Kartridg-Pak, Inc. may be fitted with either molded seals or simple "O" ring seals. With the molded seals, crimp depth tolerances of ±0.005" ( ± 0.13 mm) can be held, but problems leading to production line slow-downs may occasionally develop. The "O" ring seals give better overall machine performance, but the depth tolerances must normally be increased to ± 0.008" or so. A broken piece of a segmented collet can be replaced with a new one. However, this practice may produce an unbalanced collet, where the new tooth may indent the valve cup somewhat more deeply than before, or produce a groove a few thousandths higher or lower than before. It is often better, whenever possible, to replace a broken segment with a used one from another collet. In any event, the repaired segmented collet should be checked carefully by crimping a few cans and measuring the diameter and depth of the six indentations. Alterations in the new segment can sometimes be made by careful grinding. A particularly good crimp must be made whenever the aerosol formulation may be expected to exert a strong solvent effect on the flowed-in compound gasket, or whenever the formulation will cause gasket shrinkage. Some formulas, such as diethyl ether types, will often do both. The ideal aerosol composition, from a gasket standpoint, is one which will cause a mild swelling effect, in the area of 4% to 15%, without bringing about plasticizer extraction or other solvent related problems. Weight loss data, taken in part from unpublished results obtained by the Specialty Chemical Corporation, show that most of the seepage from an aerosol takes place through the valve itself. See Table XIII. The seepage weight loss from this aerosol composition is probably about 0.2 g/yr through the crimped seal, and about 0.2 g/yr through the container double SCALING MAM VALVE FEMULE RUMER CASKETS SEALING MADS VAIVE FERRULE RUMER GASKETS SEALING *£AC« VAIVE FERRULE Figure 18. Glass Valve Figure 19. Latent Leaker Figure 20. Plastic Bulged Correctly Crimped Incorrectly Crimped Too Loose Crimped Too Tight and Too High
Crimping 301 Table XIII Weight Loss Through Precision Valves, for a Hair Spray in a 202x509 Can Time in Storage (mo.) 1 3 6 9 12 75" 0.2 0.5 0.9 1.6 2.0- Bu na Gaskets 100 0.3 1.2 2.1 3.3 4.5 130 0.4 2.6 — — — Wei 75 0.1 0.4 0.6 0.9 1.2 ight Loss During Neoprene Gasket 100 0.3 0.8 1.4 2.0 2.8 Upright 130° 0.5 1.5 — — — Storage of H 75 0.0 0.2 0.3 0.4 0.6 Vi air Spray ton Gask 100 0.1 0.2 0.6 0.9 1.2 (Grains) ets 130 0.1 0.3 — — — Blar 75" 0.0 0.0 0.2 0.3 — ik Valve Cup 100 0.0 0.1 0.1 0.3 — 130 0.1 0.2 0.3 0.7 — Simulated Hair Spray Formula: (Fill - 200 grams) Propellent-12 25% 1,1,1-Trichloroethane 10% Ethanol - Anhydrous 50% Methylene Chloride 15% seams, at a temperature range of from about 70°F to 105°F. These figures are quite low, considering that the average aerosol container shows a weight loss of about 3.0 g/yr. Methylene chloride, acetone, xylenes and Propel- lent-21 are ingredients which cause strong solvent and leaching effects upon the flowed-in gasket compound. They are profound gasket swellers, often causing the gasket to expand and push partially out of the normal position, provided they can contact it sufficiently well. Weight losses of products high in these solvents will often be in the range of 6 to 12 g/yr. Ethanol, isopropanol, diethyl ether, propylene glycol, polyethylene glycols, Propellent-12 and Propel- lent-114 exert either a negligible swelling effect, or a shrinking effect upon ordinary Dewey & Almy GK-45 NVH neoprene-based gaskets. The shrinking effect of ethanol is about 7 v%. In the case of products containing these solvents without die presence of substantial amounts of swelling type solvents, such as personal deodorants, feminine hygiene sprays and engine starter fluids, the gasket must be drawn up very tighdy during the clinching operation, or leakage may result. This type of leakage is often described as "latent leakage" since it does not commence until a certain degree of gasket shrinkage has taken place: a matter of a few weeks or months. For example feminine hygiene sprays have been crimped most successfully into tinplate cans, less successfully into beaded aluminum cans with one-inch openings, still less successfully into beaded aluminum cans with openings for 20 mm ferrule closures, and with least success into aluminum tubes with "corrugated" finishes, also designed to accommodate die 20 mm ferrule-type closure. In any closed aerosol system die gasket compound tends to build up an equilibrium relationship with the formulation after about two weeks. At this time, die rate of weight loss stabilizes, and several other parameters also cease to fluctuate. The effect of the solution upon the gasket is direcdy proportional to die availability of contact between the two. A tight crimp will strongly reduce diis contact, but maintaining the dispenser in an upright condition will also be quite beneficial. The use of lower temperature storage reduces die concentration of vapors in die outage space and also minimizes the solvent activity of diese vapors. These considerations show die wisdom of storing aerosols cool and upright, wherever possible. Certain gasket materials are more resistant to aerosol solutions dian others. For instance, Dewey & Almy GK-70 material is less affected by edianol and diethyl ether than is GK-45, and is therefore a preferred composition for use widi diese solvents. More on diis is presented in die section dealing specifically widi flowed-in valve gaskets. Measuring the Finished Crimp Crimped aerosol cans are measured for crimp diameter and depth widi good frequency in any well organized operation. See Figures 21 and 22. In a few instances, especially where the product is hard to hold,
302 The Aerosol Handbook me can is measured for diameter between crimp indentations. This figure varies, but is often about 1.040". When it becomes less, there is a possibility of leakage between indentations. Double crimping, which statistically will remove over 90% of diese higher areas, has been shown to reduce the seepage rate of personal deodorant formulas (mostly edianol and P-12) to less man half me former averages. It is not feasible for production purposes. Finished aerosols are sometimes checked by means of a torque tester. The tester developed by Dr. Winston Reed is by far the most popular in die U.S., and is available as a set of specific tools widi accessories designed to clamp onto die housings of various aerosol valves. Under no circumstances should any torque tester clamp outward against die crimped seal, or inward against die maximum diameter of die valve cup, since this will distort die very area under measurement. Widi die tester attached, die can is held rigidly in place and die torque arm is slowly rotated, noting die dial gauge, until die valve cup begins to turn in its seat. The maximum dial reading is recorded. As a rule, a value of between 30 and 60 inch-pounds indicates a satisfactory crimp. This test, which has die disadvantage of destroying die aerosol unit, is a poor measure of comparative sealing efficiency. The torque reading is a rough summation of such conditions as: a. Out-of-roundness of die crimp sealing area, as ellipticity. Figure 21. Kile Gauge for Crimp Diameter A dial read-out crimp diameter measuring gauge, made by the Kile Machine Shop, Danville, IL. Considered by many to be the most accurate and reproducible device available for such measurements. Operation is simple and direct. J *<> b. Smoodi versus rough finish on die gasket compound. c. Burrs or odier interruptions of die smoodi metal surface. d. Lubricity of product spills on die can-to-valve interface. e. Formulation of plastic jacket of aerosol botdes in relation to frictional effects. One cannot determine what portion of all these extraneous conditions is present to affect die final reading of crimp tightness. The test will definitely not determine gasket diickness variations, gasket channels, grooves or odier imperfections, or slight-to-moderate can bead distortions. The Reed instrument, complete widi various accessories, costs about $420. Torque testers are in use in die United States, Canada, and Italy, but do not seem to be widely used elsewhere in the world. Perhaps die best method of full laboratory crimp evaluation, but used to a limited extent, is die determination of crimp profile. A gauge for tiiis purpose is shown as Figure 23. It has been used to determine tiiroat profiles of a given can bodi before and after crimping, as illustrated in Figure 24. W.E. Hensen and J.W. Thomas of S.C. Johnson, Inc., described such a mediod, which diey developed, at die May, 1970, meeting of die CSMA Commercial Standards Committee in Chicago. They pointed out Figure 22. Kile Crimp Depth Dial Gauge Unlike some gauges, the depth is read as the distance below a knife edge laid on the crown of the valve cup, directly over the crimping indentation to be measured. Thus, any non-planarity or molded cap seal impressions are not able to influence the determination. c /
Crimping 303 © ^. Figure 23. Kile Gauge for Throat Profile A compound gauge for the determination of throat profile in the depth range of 0.06 to 0.25 * (1.52 to 6.35 mm) below the top plane of the can bead. A dial gauge radius may be read for each depth setting of the needle connected to the barrel micrometer. Readings are then plotted to show contour. Made by Kile Machine Shop, Danville, IL. Figure 24. Throat Profile Graph .500 y NSQ -si -^ THROKX PH0f.lLE. ^-—■ —s-^. *N AMERICAN CAN COMPANY ".. j: ,£O2'S09 CAN ' ! j 1 ! ""NA $Q 30-LI91 NO. 90798 -CHICAGO \\\\ \ . ptr^ENptqN& h TOTAL CAN HEIGHT j\ PUJ& X.D. » j COAL. O.O l ! CURL. DIAMETER. IM0*U-) ,'* / CUflL *fi" rHMBNSION aerobe,-'' -' e.A ma. point op hard ,„-' y' CONTACT (A) ^,^'APTER CRIMP OlAMBTeP. "■^f--^. CRIMP OEPTH ^"^Ov GAP f.9ADPL£> DIAMETER \\ COLLET SEGMENTS A--^\ NOTE DOTTED t-MEB A N/N^ THROAT PfiQFtL.E ', \ ^^£J£fORE CRlMPfN* THROAT PPOFILd . ' — AFTER CRIMPING- . .530 .Gil .TOO .«2f, .1150 .(J?5 .TOO BEFORE J.33S". C.9M" l.£ffc" O. HZ' O.tZI* O. lk$S" - - - - AFTER . . .CfUMPjfita ! s.aat* , , OM3' *. 333"*. a./|i". ! O IIS" . . o. /xsefi I.07& *O.OJOO* <5.«Z5* 0.0005 j.otr^o.ooi" 6 HE ESTIMATES- .725 ZI-JM-I98L .750 .775 XNNER THROAT F*RQFtLE FOR JtOZ-tMAMErER AtfEtA/CAN CAN COMPANY CAN -CHICAOOFU.ANT. BMPORC AND AFTB.R CffWftW- XN THIS CASS CRIMP/H0 DBPRMMMO rop OP GVA*. mr o.oie" aho CAvsmo fiattenm* ©f both cv*l ah0 ovsr covet apma op vomm. A ■ POINT OP HARD CONTACT (SANA OAVtG. RA1IILS (Moas il from vertical ccnlcrllne ol container.) (inches) Figure 25. Inner Throat Profile Graph that, when an investigator measures crimp diameter and depth, he sees and studies only the external configuration of the crimped valve. It was their purpose to see what actually happens inside the can after the valve is crimped, and thus be able to observe the cause of the crimping problem. They observed mat the method of examining the cross section of a crimped valve by exposing a cross section by cutting would provide some insight into crimp integrity. However, this mediod would not allow them to observe the actual state of the crimped valve, because me very act of cutting dirough the can dome with a saw would release pressure on the dome, permitting it to spring from the crimped position and resulting in deformation of me crimp seal. What diey determined to do to avoid this problem was to cast die can dome and crimped valve in plastic before cutting through dome and valve widi a saw. They would dien examine the exposed cross section under magnification. The stepwise procedure is as follows: a. Puncture can base and expel die contents. b. Remove dome at top chime widi EKCO can opener or similar instrument. Wipe dome and valve section clean and dry of product. Remove diptube. c Pour liquid resin into casserole for casting. The resin (Castolite Company, Woodstock, Illinois) is mixed widi one part catalyst to 99 parts resin. Immerse can section in resin, using care to minimize trapped air. d. Place sample in vacuum chamber at about 20" Hg° for 15 minutes to further remove entrapped air.
304 The Aerosol Handbook e. Allow resin to harden slowly over 24 hours at 40°F. Tacky resin is then conditioned at about 110°F for 2 to 4 hours until hard. f. Make a vertical cut dirough die center of die valve, using a fine toodi band saw. g. Rough polish sample on a drum sander to remove saw toodi marks. h. Do final polishing widi waterproof abrasive paper in a sink with water runing continuously over sample. Polish widi #320 paper and men #600 paper. i. Dry and polish widi Johnson's "Favor". j. Project sample image widi Model 814 Ex-cell-o contour projector set for 10 x magnification. Tracings of die image can then be prepared. k. Relate tracing to standards in effort to determine cause of crimp failure. Preparation time for a sample is approximately 30 minutes, and it takes an elapsed time of approximately 24 hours from start of die test until die sample can be inspected. Thus this mediod will, die developers believe, be limited to crimp study projects or production troubleshooting studies, and is not adapted to routine production application. Most crimp failures are the result, not of a single out- of-specification dimension, but of two or tfiree which reinforce each odier — acting in concert. Thus, a slighdy low crimp depdi of 0.192 " (4.88 mm), will not ordinarily cause any problems—unless die crimp diameter is less than about 1.060 ", or die can curl diickness is less dian about 0.123 ", and so forth. Many crimp problems seemingly solve diemselves when a new lot of cans or valves is brought in. But actually, die new component may simply have dimensional attributes that act to correct die deviation of some odier factor. Table XIV Crimping Dimensions for "Sepro-Cans" and Effects Thereof Crimp Can No. Diameter Crimp Depth Can Condition 1. 1.075 " 0.150 " Depth too shallow so bag is almost severed. Can curl is deformed. No immediate leakage. 1. 1.070" 1.175" Good crimp. No tendency to cut the bag or deform curl. No immediate leakage. 3. 1.060" 0.190" Depth too deep. Giving very loose crimp which immediately leaked. Crimp failures widi glass and plastic-coated botdes often give rise to latent leakers through die rubber-glass interface. In one major instance of such leakage, 0% showed leakage up to ten days, 17% showed leakage between ten and fourteen days, and about 2% showed leakage between fourteen days and diree months. Non- leaking samples of diis lot were easily forced to leak by cycling from -20°F to 130°F to -20°F in as litde as diree cycles. By means of a new mediod for crimp evaluation, originated by Edmund Budzilek* and now an official CSMA mediod written into the Aerosol Guide, it has become possible to define a good crimp depth in terms of the dimensions of die valve components and botde finish. Latent leakers may be eliminated if diis procedure is followed. It is described more fully in die chapter on Glass Aerosols. The crimp depdi on ferrule type valves can be determined by means of an optical comparator, by vernier calipers, or by means of a "ball-and-anvil" gauge similar to diat described for die determination of contact height. These dial gauges have so far been made to order by two or more large marketers who specialize in glass and plastic coated glass aerosols. They are not a commercial item. The Kroplin S-2002 "ball-and- anvil" gauge for contact height can be used for die determination, widi only slight modifications and insertion of a correction factor. Ferrule crimps made on small aluminum tubes must be considered using the same parameters as for glass botdes. The tube end will be either curled or waved. Trigonometry can be used to derive clincher settings, based upon die metal of die tube protruding at least 35% into die large rubber sealing gasket of die valve. It is necessary to press down radier forcibly upon valve ferrules to help get die penetration into die rubber needed to create a hermetic seal between die valve and die glass or aluminum container. The use of proper hold-down devices or "nests'' is valuable in minimizing valve distortion. The nest should be contoured for each valve used. The "Sepro-can" carries a dome widi slighdy enlarged plug diameter and smaller curl size. Based upon known variations occurring widi "Sepro-can" dimensions because of die extra variable due to die "Conoloy" or polyediylene bag, these specifications should be used only as a general guide for set-up purposes. *E. Budzilek is a world authority on glass aerosol technology and is currently a consultant for the Wheaton Aerosol Company.
305 AEROSOL PROPELLENTS 10 An aerosol propellent is defined as an essentially non-toxic aeroform fluid capable of exerting pressure when held in a sealed container at room temperatures. A more specific industry definition enlarges the scope to those fluids which boil at or below 105°F (40.6°C) at normal atmospheric conditions. This has the effect of including methylene chloride as a propellent. Anomer definition considers what is termed die "true propellent' ': a material capable of expelling the contents of an aerosol container. Such commodities as trichloro- monofluoromediane (P-ll), isopentane and methylene chloride would men be excluded. According to regulations issued by the Department of Transportation (DOT) in the U.S.A., all true propellents are identified as compressed gasses. Within industry circles, this term is more or less reserved for the high pressure propellents, such as emane, carbon dioxide, nitrous oxide and nitrogen. Almost all the aerosol propellents exist as liquids at room temperatures. Exceptions are gases like nitrogen and helium. Emane is borderline, wim a critical temperature at 90°F (32.3°C) above which the liquid phase cannot exist. Propellents can be classified broadly as: a. Fluorocarbons i. True fluorocarbons CwHxFy. ii. Chlorofluorocarbons CwHxClyFz iii. Bromochlorofluorocarbons C^BRxCl^ b. Hydrocarbons CWHX c. Ediers i. Dimediyl edier and homologues CwHxO ii. Terra- and perfluorodimemyl CwHxFyO ediers (Discontinued) d. Compressed Gases CO2, N20 N2, A, etc. e. Memylene Chloride CH2C12
306 The Aerosol Handbook f. Miscellaneous i. Methyl bromide (fumigant) CH3Br ii. Ethylene Oxide (sterilant) C2H40 The earliest aerosol propellent was undoubtedly carbon dioxide, recorded as early as the 1860s in U.S. Patent 8,834 and odier documents as a means of expelling milk products and odier beverages in aerated form. Fifty years later Gebauer and other firms sold cans and glass tubes of ediyl chloride (B.P. = 54°F or 12.3°C) to chill and partly anesdietize the skin prior to minor surgery. The most popular was Kelene, by Gebauer. In Rotheim's early patents, starting about 1931, die Norwegian "fadier of aerosols" recognized the advantages of using liquefied gases to expel products out of cans. He used various hydrocarbons, mediyl chloride and dimediyl ether. Some of his samples survive today, in working order. During the 1930s Thomas Midgley of E.I. duPont deNemours Co. developed a number of fluorinated refrigerants, of which Freon 12 was the most important. U.S.D.A. scientists Lyle Goodhue and William Sullivan used Freon 12 in 1943 to develop their famous ' 'World War II Bug Bombs'', which usually contained about 90% of the propellent. Beginning about 1947 odier firms started joining DuPont in the manufacture of chlorofluorocarbons for bodi aerosols and refrigeration purposes. The hydrocarbon gases, which became the dominant propellent type worldwide in 1979, did not actually attain any importance until 1954 because of a general lack of low-odor material, plus a strong feeling that they were too flammable to be used safely in aerosols. Three diings happened in 1954: the first reliable mechanical break-up valve was developed (at Risdon Manufacturing Co.), Phillips Chemical Co. started to offer bulk quantities of essentially odorless "Pure Grade" propane and butanes, and a famous court batde started that upheld a U.S. Patent on the use of chlorofluorocarbons propellents for shave creams. This had the effect of precipitating the industry into water-based hydrocarbon products, such as window cleaners and shaving creams. Technically, three ethers qualify as aerosol propellents, using the expanded 105°F (40.6°C) definition: dimethyl ether (B.P. = -12.1°F or -24.5°C), methyl emyl ether (B.P. = 51.4°For 10.8°C) and diediyl ether (B.P. = 94.1°F or 34.5°C). Dimethyl ether has unique solvent properties and is fast gaining in importance. The memyl ediyl ether will probably not ever be used. The pressure is too low and toxicological clearance costs would be very high. In the case of diediyl ether we really have a product, rather than a propellent. It is used uniquely in engine starter aerosols, where a typical formula would contain 90.5%, plus about 0.5% of lubricating oil and 9% carbon dioxide. The carbon dioxide provides a good pressure which survives rather well even at -25°F (-31.7°C), which is a requirement for this particular product. The fluorinated ether propellents, typified by 1,1,2,2-tetrafluorodimethyl ether (CHF2 • O • CHF2) and perfluorodimediyl edier (CF3 • O • CF3) have been offered first by W.R. Grace & Co. and later by Phillips Chemical Co., but are now discontinued, probably due to cost and die expense of completing the toxicological studies. They would have been ideal propellents from a number of important aspects. Those fluids which are handled as liquid propellents extend from ethane/propane blends (B.P. = -50°F or -45.6°C) to the chlorofluorocarbon known as P-114 (B.P. = 38.4°F or 3.6°C). These pure or blended liquids are contained in sealed pressure tanks and normally gassed into aerosols either through die valve (T-t- V) or around the valve cup (U-t-C). In rare instances, the non-flammable, chlorofluoromethanes may be filled by refrigeration methods, which (incidentally) was once die dominant method for adding propellent to aerosol containers. On die world scene at least two firms are adding hydrocarbon propellents to containers by a cold fill mediod, but diis is considered extremely dangerous from a flammability standpoint. The higher pressure aeroform liquids, such as carbon dioxide, are stored in "receptacles," where the internal pressure is maintained at about 300 psig (2.07 MPa) by a combination refrigeration and heating system. A gas stream is withdrawn from the outage space and piped to the gassers or gasser-shakers, as die case may be, for injection into aerosol units. Even though the liquid temperature in die heavily insulated "receptacle" tank approximates 0°F (-17.8°C) at equilibrium, significant withdrawals from the gaseous phase results in cooling of the liquid, so that a heating unit must be used to restore the original temperature. Of the non-liquefiable propellents only nitrogen gas is of commercial importance. The gas is purchased normally in die form of unitized banks of five-foot (1.52 m) cylinders, all piped to a common outlet. The cylinder pressures, which start about 3000 psi (20.7 MPa), are
Aerosol Propellents 307 reduced to about 250 psig (1.72 MPa) using a pressure regulator and the medium-pressure gas stream is then piped to the U-t-C gasser or gasser-shaker machine used to inject the propellent into aerosol cans. Larger installations are very rare, but in such cases cylinders of liquid nitrogen are used. The gas may be employed also in aerosol plants for dry blanketing of tanks containing moisture sensitive materials, and for the purging of moist air from aerosol containers to be filled with these same materials. The non-liquefiable propellents could also include argon, air and methane, all of which have been looked at, although probably none have been used to any significant commercial extent. They are sometimes called "fixed" or "permanent" gases. Nitrogen and the related gases probably are not used to pressurize more than about 0.1 % of all aerosol cans. Many aerosol formulations are pressurized using a single propellent, and this has certain advantages in terms of pressure uniformity during use of the product, but limits the formulator in terms of pressure selection, delivery rate and other parameters. As a result, many aerosols use blends of two and sometimes three propellents. In addition to improvements in the product, these blends sometimes provide economic advantages. Perhaps the most common of all propellent mixtures are those of propane and isobutane. They offer the formulator a pressure range of from 31 to 109 psig at 70°F (214to751kPaat21.1°C). Although very few blends are technically contra- indicated, there are many that provide no particular formulation or economic advantage. Examples of useful blends include the addition of modest amounts of propane to isobutane to get Propellent A46, which is the standard blend for shaving creams. Widi isobutane alone, a puff of shave cream foam would undergo some residual expansion, but with Propellent A46 this does not occur. Going higher in pressure than Propellent A46 serves no purpose and could even require an extra- strength container. Another example is the addition of P-l 1 to isobutane to reduce the production of irritating, air-borne dust in the case of hydrocarbon-propelled antiperspirants. The P-l 1 helps to carry the aluminum chlorhydrate particles to the underarm area, after which it evaporates quickly. This particular application of P-l 1 is now prohibited by regulation in the U.S.A. but a very similar effect can be achieved by replacing the isobutane with a mixture of about equal parts of propane and isopentane. In diis case, the isopentane acts as the carrier fluid. As a last example, a rather old patent covers the addition of 15% carbon dioxide to nitrous oxide, to give a blend that has neither die tart taste of CO2 or the sweetish taste of N20. The blend, sometimes called "White's Propellent", has been used in pressurizing whipped creams. Production considerations are important whenever propellent blends are specified. For the filler without propellent blending equipment, die stipulation of a new blend may require the allocation or purchase of a bulk storage tank and associated foundation, pump, filter, piping system and so forth. In 1979, such a storage system cost $45,000 installed; by 1981 this had risen to $56,500. Many of the larger aerosol fillers have either manual or digital (automatic) blending equipment. In 1979 a typical Foxboro Corp. two-stream manual system cost about $11,500 exclusive of tankage requirements. The cost rose to $14,000 during 1981. Automatic installations are more convenient, but breakdowns require repairs by the supplier's service personnel as a rule, with more lengdiy downtime of the equipment. For a two-stream automatic system the 1981 price was $46,500 and for a three-stream system $57,500, again excluding tankage needs. One thing to keep in mind with such systems is that the quantity of blended propellent should not exceed the production requirement. If it does, the heel quantity in die line tank will have to be adjusted specially to revise it to the subsequent blend. A final approach to die production of aerosols widi two propellents is to fill the propellents separately. The chlorofluorocarbon antiperspirants provide a classic example of this technique. The concentrate, consisting mainly of aluminum chlorhydrate and isopropyl myri- state, is slurried with cooled P-l 1 in a sealed vessel. The mixture is then transferred to a filler by means of a recirculating piping system. After filling into cans die P-l2 is added. In a more complex fashion, blends of carbon dioxide and hydrocarbon are added separately to aerosol cans, first by injecting die CO2 via the Kartridg-Pak "Under-the-Cap" (U-t-C) gasser by an impact gassing technique, after which the sealed units move downstream to a "Through-the-Valve" (T-t-V) gasser where the hydrocarbon is added. Careful attention must be paid to die relationship of pressure and container strength in this type of gassing operation. The Chlorofluorocarbon Propellents During 1971 the U.S.A. aerosol industry used about 420,000,000 pounds of chlorofluorocarbon (CFC) pro-
308 The Aerosol Handbook pellents, about 57,000,000 pounds of hydrocarbon gases, and only a few million pounds of the other propellents. The hydrocarbons were almost always used as propellents for water-based aerosols, but rarely for anything else. In fact, their only significant application in anhydrous formulas was in hair sprays. They were added in amounts up to about 11 % to make the product more economical yet not too flammable. As in previous years, the main CFC propellent was P-12, followed closely by P-l 1 and then by P-l 14. The remaining CFCs aggregated only to about 1 or 2% of the total usage. The CFCs were used in about 55% of all U.S.A. aerosol products. In Europe, which in 1971 had an aerosol production about half the size of that in North America, the CFCs accounted for at least 85 % of the units sold. During the following five years (1971 thru 1976) modest additional inroads were made by the hydrocarbon propellents, so that in the peak CFC production year of 1976 in the U.S.A. only about 51% of all aerosols still used CFCs, either as the total propellent or as a significant portion of a blended CFC/hydrocarbon propellent. This was the lowest percentage figure of any country. In the U.K. during 1976 about 64% of all aerosols contained CFC propellents. In the less advanced countries domestic productions carried from about 80% to 100% CFC type propellents. In 1972 the CFC producers became concerned about the ultimate fate of these very stable gases after they were released into the atmosphere, so they formed what is now the Fluorocarbon Program Panel under the aegis of the Chemical Manufacturers Association (CMA) in Washington, D.C. to study the situation. Among other activities, the panel retained Dr. J.E. Lovelock of Reading University (England) as a consultant. Using extremely sensitive gas chromatographic detection equipment he was able to detect traces of P-l 1 and P-12 in the troposphere. Concentrations were in the order of 100 ppt (parts per trillion) and the measuring threshhold of the instrument was about 10 ppt. Lovelock's figures were a key factor in advancing the research of two atmospheric scientists in California, Professor F.S. Rowland and Dr. M.J. Molina, who published their hypothesis of ozone depletion by CFCs in 1974. This highly controversial theory, which is still unproven eight years later, brought untold agony to the aerosol industry worldwide, but nowhere more acutely than in the U.S.A., where regulators in the E.P.A. and F.D.A. invoked a virtual ban on non-essential aerosol uses of the CFCs. Rowland and Molina Theory The theory specifically dealt with P-ll and P-12, which are by far the most common two CFCs and probably make up about 85 to 90% of all CFC emissions to the atmosphere. However, Roland and Molina considered other fully halogenated CFCs, such as P-l 14 and P-l 13, to be just as dangerous, and suggested that there were significant risks in the case of hydrogen- containing chlorofluorocarbons (as P-22) and some chlorinated hydrocarbons. The degree of risk was related directly to the stability of the vapors in the atmosphere and the chlorine content. The main elements of the theory can be summarized as follows: a. For CFCs P-ll and P-12 the quantities measured in the atmosphere are approximately equivalent to the total amount produced since the 1930s, thus there appear to be no destructive processes of any significance in the troposphere. b. The CFCs are diffusing slowly into the stratosphere. c. At sufficiently high altitudes they are decomposed by the sun's ultraviolet radiation to liberate chlorine atoms which are then available to initiate a cycle that has the destruction of ozone as the net result: CC13F (P-ll) + hv (radiation) - CC12 F + CI CI + O3 - CIO + O2 CIO + O - CI + O2 d. The CI is removed from its active ozone- destroying status by certain reactions, for instance with methane gas to produce HC1, which is inactive so far as ozone is concerned. Eventually the HC1 diffuses downward and is removed by rain. Not all the HC1 suffers this fate however; some reacts with OH radicals, forming water and regenerating the original CI. e. All the relevant stratospheric chemistry had been taken into account in building their model. Based upon the new hypothesis, Rowland and Molina then did a calculation utilizing the limited information then available about reactions, reaction rates and other phenomena in the lower stratosphere, about 20 miles (32 km) high, where ozone has its greatest density. There are over a hundred reactions now recog-
Aerosol Propellents 309 nized as important within the ozone layer. The significance of many was not recognized in 1974. Where rates were not available, they were estimated, sometimes arbitrarily. Thus, having reduced the complexity of atmospheric physics into mathematical equations, the scientists cranked diem into a computer capable of doing a time-dependent one-dimensional analysis (die single spatial dimension was vertical) and came up with results that indicated that the continued release of CFCs at the 1972 rate would result in an eventual reduction of stratospheric ozone of about 7 to 13% — and diat diis would take about 100 years to develop, owing to the slow transport of CFCs to die ozone layer and the mechanisms involved. Even diough most CFC vapors are four or five times as dense as air, when diey are released at die earth's surface, wind currents disperse them throughout die troposphere within just a few mondis. The troposphere is the turbulent atmospheric layer nearest the earth, extending up between 6 to 12 miles (10 to 20 km), where winds blow, rain falls and temperatures decrease with altitude. At die top of die troposphere is the tropopause, die transition layer separating die troposphere and stratosphere. The temperature at die tropopause averages -67°F (-55°C). Above die tropopause lies the huge stratospheric layer, extending up anodier 20 miles (32 km) or so to die stratopause and, above die stratopause, die meso- sphere. The stratosphere is characterized by lateral wind currents (the lowest of diese are the familiar "jet streams"), relatively litde vertical air motion, an absence of particulate moisture except for very tall diunderheads, and a gradual warming with increasing altitude, up to about 28°F (-2°C). Once the CFC molecules pass through the tropopause and into die stratosphere they take an average of ten years to travel upward anodier 15 miles (24 km) or so into die upper reaches of the broad ozone layer, where they can be bombarded effectively by the shorter wavelengths of die sun's ultraviolet light, as yet not filtered out by resident oxygen and ozone molecules. The bombardment slowly generates CI which, it is theorized, then attacks die ozone. This extended time- scale, or lag effect, prompted Rowland and Molina to state mat we could not afford to wait for empirical proof diat die ozone layer was being depleted, thus proving the hypothesis, before deciding whether or not to take action. In addition, diey said diat the accumulating burden of CFCs in die troposphere provided die system wim so much inertia diat even widi a total immediate ban on further production die depletion of ozone would increase for about 15 years. Anodier 50 years would be needed for die depletion to fall to half die maximum value. In 1974, the year the hypothesis was first publicized, worldwide CFM (the saturated chlorofluoromemanes; e.g. predominandy P-ll and P-12) was 2,028 million pounds or 920 metric tons. This figure includes an estimated 10.8% contribution from die communist countries, in addition to die reported data. About 93.9% of me annual production figure, or some 1,904 million pounds (865 metric tons) in 1974 was emitted to the atmosphere in eidier that year or shortly mereafter. CFCs packed into aerosols, or used for sterilant gas mixtures, flexible foams or solvents were 100% emitted. Those used in refrigerators, air conditioners and rigid foams were emitted slowly. Aerosols accounted for 75.6% of me total emissions, and just two categories, antiperspirant/deodorants and hair sprays, made up over 77% of die aerosol total. Rowland and Molina recognized these relationships, at least to some extent, and diey responded by calling for an immediate total ban on the use of CFCs in aerosols, which diey deemed "non-essential" in any event. The news media were quick to single out aerosols as destroyers of the earth's protective ozone layer, and concentrated dieir attack on underarm and hair care products, calling them the worst offenders of all. The scientific community reacted quickly to the Rowland and Molina Theory, and to their strident warning diat die situation was critical. Despite the fact diat die supporting evidence was very limited, and mat experimental verification of the dieory was largely lacking, many atmospheric scientists regarded die hypodie- sis as sufficiendy plausible to be taken seriously. The prestigious National Academy of Science studied the dieory and its portents in 1975 and concurred that there might indeed be a looming problem of major proportions. One committee chairman suggested strong federal action to limit CFC emissions, at least until more scientific investigations could be conducted to prove or disprove the theory. Investigations were started radier quickly, and produced isolated results of limited merit, especially when die audiors concluded diat diey either proved or disproved the hypomesis. A very large number of more detailed and difficult experiments are now in progress and sound results have begun to emerge.
310 The Aerosol Handbook Preliminary Atmospheric Chemistry Without any doubt the presence of stratospheric ozone is beneficial to life on earth by absorbing harmful ultraviolet radiation. Non-melanoma skin cancers have been ascribed to many years of human exposure to sunlight high in ultraviolet content. While non-melanoma skin cancers are the most common skin cancer for Caucasians, they are also the most treatable form of skin cancer. Malignant melanoma, a much less common but life-threatening skin cancer, on the other hand, does not appear to be linked directly to exposure to sunlight. Some scientists feel that Caucasians may suffer about a 2% increase in the incidence of non- melanoma skin cancer for every 1 % reduction in the amount of stratospheric ozone. During the mid-1970s a German team even went so far as to develop a tenuous hypothesis that the precipitate demise of the dinosaurs was coincident with a supernova some 90 million years ago, which depleted the ozone layer by at least 50%. Not having the protection of a furry, hairy or scaley coat, they succumbed to skin malignancies. Fanciful stories such as these were very much in the news during 1975 and 1976. A second concern was the effect that increased ultraviolet radiation might have on the food chain. Animals should be relatively immune, but marine life forms might be affected, since ultraviolet light can penetrate several meters into clear water. Bacteria, algae and plant life also might be affected. The major question of all this is the matter of degree. Life forms can adapt to environmental changes up to certain limits. Thus, a 5% depletion of the ozone layer might pose no significant problems, while a 50% reduction could be disastrous. Although much of the science has yet to be developed, there are many known examples of beneficial effects in insect, plant, marine and crop life, but they have received scant mention outside of trade and technical journals. The third and last concern is that of the so-called greenhouse or temperature elevating effect that might result from an attenuated stratospheric ozone layer. In 1980 the EPA claimed that climatological effects of a projected eventual 16.5% ozone depletion would include an increase in the mean, global temperature of perhaps 0.6°F (0.3°C) and that this would be significant, causing an expansion of desert areas, reductions in crops and melting of polar icecaps. Yet, in other reports prepared for the agency in that same year, it was concluded that modest warmings of up to about 1.5°F (0.9°C) might be beneficial, whereas larger ones like that projected for C02 effects — 5.5°F (3.0°C) from 1982 to 2035 — would be adverse. Actually, the warming trend predicted from many sources indicates that CO2 will be ten times as important as CFCs as the causative agent. CO2 levels have risen from an assumed pre-industrial level of about 250 ppm (more scientifically expressed as 250 x 10"6 VMR, or Volume Mixing Ratio) to 340 ppm in 1983 and might increase to 680 ppm by the year 2035. Aside from the noted average global increase, such warmings are calculated to reach as high as 13 to 18°F (7 to 10°C) during the winter over the North Pole area and could lead to a 20 foot (6 m) higher ocean level by the end of the next century. All of these effects are based on projections widi large uncertainties. The carbon dioxide greenhouse effect is based on the concept diat increased carbon dioxide would alter die way the earth loses heat. Incoming radiation warms the earth's surface, which loses heat by radiating infrared radiation into space. Observed temperatures thus result from the dynamic balance between incoming solar radiation and outgoing infrared radiation. Certain gases, including carbon dioxide, ozone and CFCs, absorb and emit infrared radiation. Increased concentrations of carbon dioxide, for instance, would absorb more of the outgoing infrared radiation, but the net process causes a "high-C02 planet" to emit radiation less efficiently than a "I0W-CO2 planet." Since incoming and outgoing energy must balance, the high-CC*2 planet warms up slightly to reestablish the dynamic balance. The process, which incidentally has virtually nothing to do wim greenhouses, is extremely complex because many other factors, including ice and snow cover, clouds, etc. would also be affected by temperature changes and can themselves affect radiation equilibria. These other factors can potentially enhance (positive feedback processes) or counteract (negative feedback processes) the highly simplified concept described. These feedback processes are, therefore, major sources of the large uncertainties associated with these calculations of long-term temperature changes. Solar radiation that includes wavelengths throughout the entire ultraviolet range strikes the upper atmosphere, but wavelengths shorter than about 180 nm do not penetrate as far as the stratosphere. Those in the range of 180 to 260 nm reach into the upper stratosphere and are absorbed by molecular oxygen, which ruptures into oxygen atoms. The energetic oxygen
Aerosol Propellents 311 ^8S? .""Sgj ^-J TT.r.r "—V- „.___ j— z='rrrr~ I"-- l- ::t_4 _~ll zz_:h^:-_ + :.-_-_■:- , 777=t77 —7-"- =T^-. ^ ^ ^^ "Zl-^ L-" - - , _.. 1 - ----K- ^+_ — — r :"_... l"^_i.i" r " S^_| ^^1*9* -"-"- r^^ :■_: .:".. —' i -:'" ■■- . ..--! ' _.--h - * .77t;^ 7rrlF7j ^pj __""_! -r-::L:--: ■ ] _": [ ' ' ^fesd : !*^^W r^ ! ■ _ I - - jjfggjS&i gggaggp 111 :-..r -.. --::|--:- "i - I ^SL ^^fc^ ^^§k ^8 ^ ;^^ -ggg^iP §ftj|j|i L- : ': - ---<--- --_: f -:j - - -- ■ : . 1."—: : !: .. i ^ yIISl !§§§» ifiHI l§f§^ wr ■ * ■ OZONE CONCENTRATION (molecules per cm-1) Figure 1. Concentration Profile of Atmospheric Ozone atoms combine with oxygen molecules to produce ozone. All the ozone in the stratosphere is formed in this fashion. The ozone inventory of the atmosphere stretches continuously from the earth's surface to at least 50 miles (80 km) in the mesosphere, by which time it has thinned out to an estimated 5 x 106 molecules per cm3, too attenuated to be measured. Figure 1 shows the concentration profile of ozone with altitude. The concentration is expressed in absolute terms: as molecules per cm3. If it had been given in relative terms, such as ppm or ppb, a very different shape would have resulted, since the air thins so profoundly at upper altitudes. For example, at 12.5 miles (20 km) the air pressure is only about 13 mm (0.25 psi or 1.7 kPa), which is 1.7% of normal pressure at sea level. Considering the maximum of the measured ozone range, an easy calculation suggests a relative ozone concentration of 2.4 ppb at sea level and one of 1.8 ppm at 12.5 miles (20 km), about 750 times higher. The ozone layer provides its greatest absorption of ultraviolet radiation at an altitude of about 13 miles (21 km). It is not truly a "layer" at all, although if one were to be fantasized it would lie conveniently in the range of 8 to 20 miles (13 to 31 km), since this band should generally contain at least 3 x 1012 molecules per cm3. The concentration of ozone is quite variable at different points on the earth. It ranges from a low of about 225 milliatmosphere-cm (Dobson Units) at the equator to almost 400 D.U. at the northern tip of Quebec. The NYC area has about 320 D.U. of coverage while southern Florida has only 275 D.U. and this 14% difference in ozone overlay accounts, in part, for the faster tanning or burning of skin in southern Florida. The comparison invites the suggestion that a 14% reduction of ozone in the stratosphere, ignoring other factors such as latitude, would cause the equivalent of Florida sunshine in NYC, and one notes that the flora and fauna of Florida are doing well. The amount of ozone at any one location also undergoes a substantial change. Ozone decreases slightly during the night and increases slightly by day. In the spring, ozone may be 30% more plentiful then in the autumn. Strong weather fronts may change the concentration by as much as 34%, although equilibrium is restored quickly. And finally there are the so-called eleven year sun spot cycles which change ozone by about 5%. Once formed, ozone itself can absorb the sun's ultraviolet radiation, breaking down into an oxygen atom and oxygen gas in the process. It absorbs most strongly at about 250 nm, and absorption is also important between about 200 to 310 nm. (A modest absorption range also exists from about 460 to 750 nm in the visible spectrum, which is why concentrated ozone looks blue.) In addition, atomic oxygen is capable of attacking ozone to form oxygen gas. Much of the early work on these reactions was done by Chapman, and they have become known as the Chapman reactions. More recently they have been described as "odd- oxygen processes" since an atomic oxygen unit or ozone itself has been involved in each. The term also has a relationship to other processes that deplete ozone. Odd-oxygen processes (Chapman Reactions): 03 + hi> (at 210 to 300 nm or so) — O + 02 03 + O - 202 Three additional processes act to deplete ozone. Each of these is a cyclic type; that is, the original initiating compound is regenerated in a catalytic fashion and continues to react until it is removed from the site by diffusion or by reacting with other compounds to form temporary or permanent sinks. The odd-nitrogen process is the most important: Odd-nitrogen process: NO + O3 - N02 + O2 NO2 + O - NO + O2
312 The Aerosol Handbook The odd-hydrogen process is very similar: HO + O3 - HO2 + O2 HO2 + O - HO + O2 By summing up eidier of these cyclic reactions die overall process is seen as one where a molecule of ozone and an oxygen atom (itself a precursor of ozone) is transformed to two molecules of oxygen gas, dius depleting ozone. The last significant reaction cycle for die possible depletion of ozone was that discovered in 1973 or so and termed die chlorine oxide cycle. Chlorinated organic compounds injected into the stratosphere from such diverse sources as volcanoes, biospheric reactions, die space shuttle, industrial emissions and aerosols could be stripped of their chlorine content by ultraviolet radiation, and the chlorine atoms might dien attack ozone. Chlorine oxide cycle: CI + O3 - CIO + O2 CIO + O - CI + O2 As before, ozone and oxygen atoms are transformed to oxygen molecules as die net result. Finally, diere are a host of minor reactions diat can, at least theoretically, act to deplete ozone. For example, bromine can be stripped by radiation from bromine compounds, and can dien react in a bromine oxide cycle, perhaps even synergizing die chlorine oxide cycle in die process, making it about 10% more potent, according to some researchers. Also, some ozone is undoubtedly lost from die stratosphere as a result of downward travel to die troposphere, even diough diis is partially offset by ozone in die troposphere formed as a result of electrical storms, combustions and other reactions, which diffuses to the stratosphere. An extremely important aspect of the three cyclic reactions is how long diey can be sustained. On a statistical basis, does an NO, HO or CI particle react with ozone a hundred times or a hundred thousand times before something happens to break die chain? The NO2 and OH entities are required for die perpetuation of their respective cycles, yet they can also react with each other to form nitric acid in die presence of a third body. Nitric acid is reasonably stable, but can be attacked eidier chemically or photolytically to some extent so that the initial oxides are reintroduced. In diis sense it functions as a temporary sink, eliminating reac- tants only for a limited time. However, if it diffuses down and is removed by rain, then it can be regarded as a permanent sink. During 1976 an important new sink was discovered, involving die reaction between CIO and NO2 to form CINO3, chlorine nitrate. As a sink, CINO3 has bodi temporary and permanent properties. It can be degraded more readily dian nitric acid, but it is also able to rapidly hydrolyse to HC1, HCIO and HNO3 widi moisture and be rained out. The introduction of CINO3 in die calculations caused many dieoreticians to reduce dieir ozone depletion figures downward to about half die earlier values. The relative importance of die known major sinks involve many factors, including die concentration of the reactants and die reaction rates. Both of diese vary widi altitude and temperature. In a crude sense, the ozone inventory can be likened to die amount of water in a baditub, with the faucet adding more and die drain partially open to take some away. The rate of "addition" is as constant as die quantity of the sun's ultraviolet radiation. The rate of "drainage" can be affected by die level of bodi natural and andiropogenic injections of ozone-depleting chemicals into die stratosphere and by die amount of ozone present. Using die data available in 1978, estimates are made of the relative importance of the major depletion reactions. This is illustrated in Table I. An indication of die sensitivity of die data to concentration and reaction rate factors can be obtained from die Cress Report No. 131, prepared by SRI International for the EPA in mid-1980. In contrast to die Sanders* data die report claims diat nitrogen oxides (NOx) are less effective in reducing ozone dian CFCs. Also, odier halogenated species are less important depleters than CFCs. During the 1970s several potential ozone direats, including die SST and nitrogen based fertilizer episodes, have waxed and waned as new information has caused changes in die results from die computer calculations. *Dr. Paul Sanders of E.I. du Pont de Nemours & Co. Table I Stratospheric Removal of Ozone (Estimated) 1. Odd-oxygen processes (Chapman) 15 to 20% 2. Odd-nitrogen cycle 50 to 70% 3. Odd-hydrogen cycle 10 to 15% 4. Chlorine oxide cycle 20 to 0% 5. Other processes 1 to 2% Bromine oxide cycle Transport to troposphere Others - known and unknown
Aerosol Propellents 313 Another factor of extreme importance is die continuing search for sinks: mechanisms that remove effectively potential ozone-depleting compounds and thus act to decrease ozone depletion rates. One type of sink would act to prevent or delay potential ozone depleters from forming in die first place. For instance, very dry sand particles, in the presence of strong sunlight, absorb P-ll and perhaps P-12 from die troposphere and possibly change diem to P-21 (CHCbF) and perhaps P-22 (CHCIF2), respectively. The presence of unexplained higher levels of P-21 downwind from die Sahara Desert has been suggested as empirical evidence of such a sink. However, researchers have not yet been able to quantify this effect. Anotiier possible sink involves die entrapment of P-l 1 in the upper layers of die Antarctic ice mantle. Some CFC emissions find tropospheric sinks in die seas, but die concentrations are quite low and fall off rapidly witii increasing deptii. Again, die significance of tiiis effect is not known. The intriguing point of all tiiis is tiiat die model calculations are very sensitive to such CFC sinks. Even slow tropospheric removal processes could reduce substantially ozone depletion calculations. Other processes witii die potential to alter present calculations are possibly to be found in die stratosphere. The products from die reaction between hypochlorite (CIO) radical and hydroperoxyl (HO2) radical are of current interest because they might help explain the high 2 and 8 ppb CIO levels found by James G. Anderson in mid-1977 and later. The theory calculates about 1.0 to 1.5 ppb. If confirmed, they could alter the ozone depletion calculations. One research team has considered the two most probable reactions: CIO + H02 - HOC1 + 02, CIO + HO2 - HC1 + O3 and commenting that, if the second reaction accounts for as much as 10% of the total mechanism, current predictions for eventual ozone depletion would drop by a factor of about three. In measuring reaction rates, frequendy only die disappearance of reactants is measured, not die rate of reaction product formation, and sometimes the nature of the products is only assumed. Yet they are quite important. If there is a significant reaction between the CIO and HO2 radicals, any HC1 formed would provide the CI moiety with an enhanced downward path to the troposphere where it could be rained out. In the same fashion, any HOC1 formed would be decomposed by ultraviolet radiation. If CI + O were formed, the ozone should increase; if OH + CI were formed, it should have almost no effect, and if H + CIO were to be formed, tiiere should be a decrease in ozone. The values given for die degree of ozone depletion have generally been based upon die model suggesting a continuous emission of CFCs at die 1976 levels, until a steady state is reached, sometime after about 2100. Steady state is approached asymptotically, so tiiat the selection of an actual date becomes somewhat arbitrary after about 2060. The values start with a 1974 range of 13 to 18% ozone depletion, as proposed by Rowland and Molina. As the science progressed they fluctuated, both up and down, and the present values are mostly between 5 to 7 %. The theoretical variations are shown in Figure 2. In addition, it is appropriate to recognize that uncertainties remain with the latest and much lower calculations, and that further revisions are likely. A limitation in the theories set forth by Stolarski and Cicerone, Rowland and Molina and other atmospheric scientists during the mid-1970s is tiiat they were % DEPLETION' OF STRATOSPHERIC OZONE Figure 2. Per Cent Distribution of Stratospheric Ozone
314 The Aerosol Handbook necessarily based upon one-dimensional computer models. The atmosphere obviously has three dimensions, and to analyse such complex components as the ozone system by the use of a one-dimensional scenario requires major simplifications. Crudely put, it is a bit like trying to define and describe a person by looking at the individual through an extremely thin slit. In addition to assumptions that had to be made concerning reactions and rate constants, further assumptions were required to accommodate limitations of the computers. Although the investigators admitted that they could not handle many known complexities, because of die fixed parameterization of atmospheric dynamics which is an adjunct of one-dimensional modeling, and were therefore resorting to concensus assumptions, this important fact was apparantly lost on the press and the regulators. These groups only recognized that a number of supposedly independent groups were coming up with very similar results and conclusions, not that they were using essentially die same science, the same assumptions and the same computer hardware, so diat the development of an equivalent end product was reasonably well assured. Limited two-dimensional computer models, used since about mid-1978, show diat ozone concentrations, and any depletion, is somewhat dependent upon latitude. As mentioned earlier, ozone levels are much higher near the poles, and particularly in die north Hudson's Bay area of Canada. Somewhat greater ozone depletions are now predicted to take place during die polar winters where the intensity of ultraviolet radiation is small to begin widi, and where the attendant increase in radiation would also be low. The population above 60°N latitude is quite small and diat Table II Increase in Carbon Dioxide Volume Mixing Ratio (1800 - 2060) CO* Level Year (VMR x 10«) Historic level) 250 1800 275 1925 290 1972 325 1983 340 2020* 425 2030* 600 2060* 1100 •Assuming the burning of fossil fuels and deforestation trends are sustained. below 60°S latitude is nil. Sunbathing or odier activities involving high exposure of die skin to sunlight would be impossible in climates where the sun is generally below die horizon and die temperatures range from -30 to -75°F (-34.5 to -59.5°C). Further work elaborating on the earth's ozone system is continuing, with a significant portion funded by industry. Studies are concentrated in a number of key areas. For example, the reaction rate constants of the interactions between OH radicals and various species are leading to a lessening of the discrepancies between dieoretical and actual CIO concentrations. A better knowledge of vertical transport rates in die stratosphere is needed, since modelers have cautiously assumed very low rates, and such assumptions have acted to increase die calculated figures for eventual ozone depletion. Still further confirmations are needed to prove that HC1 concentration decreases with increasing altitudes over about 19 miles (30 km), since the observed decreases fly in the face of die theory. More work is also in progress to better define the significance of some unpredictably high CIO variations to date. Studies are needed to extend our knowledge of coupling (reciprocal interference) between the various catalytic cycles. They are interrelated so closely that they cannot be assessed on a separate basis. The continuing question of tropospheric sinks urgently needs further study. The investigators of the mid-1970s felt uiere was no reduction; that P-11 and P-12 had lifetimes in excess of 100 years. For example, if it could be shown that these CFCs are sinked (removed more or less permanently) at 5% per year, the ultimate ozone decrease predicted by the theory would have to drop by 60% or so. And finally, diere is the question about die effects of increasing carbon dioxide injections into die stratosphere. The data of Manabe, et al (J. Atmos. Sci., 1975) and other teams have suggested a growing CO2 presence in die atmosphere, as shown in Table II. Using uiis data, Luther, etal(/. Geophys. Res. 1977), Groves, et al (Nature 1978 and 1979) and odier investigators have considered die effect of increasing concentrations of CO2 on die ozone inventory. The computations all point to a lowering of upper stratospheric temperatures which would result in significant increases in total ozone column density. The photonic Chapman reactions that generate ozone are expected to proceed with increased efficiency, while the rate of any CFC depletion reactions is expected to slow. Since OH and HO2 radicals have key roles in controlling ozone
Aerosol Propellents 315 above 25 miles (40 km), any increase in tropospheric temperature resulting from CO2 increases would affect ozone by increasing the supply of water vapor to the stratosphere through the equatorial "cold trap". Although computers available to date have not been able to handle such attendent complexities as the sensitivity of atmospheric circulation to changes in radiative field in the lower stratosphere, the dynamics of transferring ozone downward, where it is better conserved, and the effect of concentrations of CO2 in excess of two times the current atmospheric levels, still the overall effect from these parameters can be analysed to show that increased CO2 significantly increases ozone. The latest paper by Groves, et al (1979) considers the effect of raising the CO2 concentration from 275 to 600 ppm (volume) in an atmosphere also containing 0.75 ppb methyl chloride (CH3Cl), 0.13 ppb carbon tetrachloride (CCU), 0.8 ppb P-ll and 2.3 ppb P-12, with the latter two molecules relating to steady state 1975 rates. This so-called chlorine chemistry model showed that the effect of increasing the CO2 level would result in an overall increase in ozone of 2.3%. A recent development of substantial interest is the ability to perform model calculations in which several emissions calculated to affect stratospheric ozone are considered simultaneously. Previously, calculations varied one emission, for instance CFCs, while the other atmospheric inputs were kept constant. This was clearly an unrealistic scenario. When CFCs, carbon dioxide and nitrogen oxides from aircraft operations and denitrification of synthetic nitrogenous fertilizers are considered simultaneously, important offsets and interactions are found to occur. To date, only calculations for the period 1960-1965 have been published (National Aeronautical & Space Agency and World Meteorological Organization [NASA/WMO]: The Stratosphere 1981 - Theory and Measurement), but these show that the overall effect upon ozone is negligible — less than a 0.2% increase or decrease for the period. It is important to emphasize that this does not eliminate the concern, since major uncertainties in the calculations remain and further scientific research is essential. However, what it does mean is that, as far as the urgency for further regulation is concerned, (1) we are clearly not faced with a crisis, (2) there is ample time to obtain a clearer scientific picture without significant risk to human health and the environment, and (3) to date there is no proof that CFCs or any of these other activities are having any real impact on ozone. Empirical Ozone Measurements The high variability of the earth's ozone inventory according to diurnal, seasonal and sunspot cycles has been mentioned. It also changes with latitude in a complex fashion. Even vulcanism is a factor. During the 1976 eruptions of Mount St. Augustine in Alaska some 400 million pounds (180 million kg) of chlorine (as various vaporized compounds) were injected straight into the stratosphere. This amounted to about 36% of the chlorine going into CFCs in that year. These disturbances have made actual measurements difficult and the construction of hemispheric or total world inventory figures even more difficult. The classical instrument for measuring atmospheric ozone is the Dobson spectrophotometer. Measurements are made in Dobson Units (D.U.), layer thickness expressed in milliatmosphere-cm. For example, the ozone column isopleth (concentration contour line) that cuts through the New York City area is 320 D.U., which means that if all the ozone were concentrated into a layer of pure gas at sea-level conditions it would be 0.126" (0.32 cm) in thickness. Ozone monitoring stations at Oxford, England and Arosa, Switzerland have been in operation since 1925. During the 47 year period ending in 1972 they measured an irregular total gain of about 6% in the ozone layer. However, the earlier measurements are subject to some questions of accuracy. A more reliable survey has come from a range of up to 39 Dobson station results between 1958 and 1975, showing a 4% gain in the Northern Hemisphere. The data in Figure 3 (Page 316) uses the results of several recent measuring sequences to suggest a 5% increase between 1954 and 1978. The significance of these increases is not known. Fewer measurements have been made in the Southern Hemisphere, perhaps because less than 10% of the chlorofluorocarbon industry is located there. CFC emissions in the Soudiern Hemisphere are also probably less tiian 10% of those in the Northern Hemisphere. With this background it is interesting to note that the increase of ozone below the equator has occured at only about 25% of the rate in the Northern Hemisphere. Again, the significance of this estimate is not known. Although the exchange rate between hemispheres is very slow, due to trade wind influences, nevertheless, there is speculation that some of the excess ozone in the north may have drifted south. This would suggest that long-term measurements of ozone over die
316 The Aerosol Handbook Northern Hemisphere have given increase figures that would have been larger, had it not been for the drain-off effect. Until about 1980 all diat could be suggested was that die sum total of natural and anthropogenic (man- made) injections of various chemicals into die stratosphere, plus other ozone-affecting factors, seemed to have caused a net increase in ozone averaging about 2 % per decade and possibly increasing in rate. It was also recognized diat about 4.7 billion pounds (2.13 million metric tons) of P-ll and 7.35 billion pounds (3.33 million metric tons) of P-12 had been produced by the Free World by die end of die 1960s, and that about 80 to 90% of diis total amount had been released to die atmosphere. Given a ten year period for die slow vertical transport dirough die stratosphere and into die upper ozone layer area, one could point to an infusion of about 10 billion pounds (4.5 million metric tons) into the ozone layer by die end of the 1970s, and yet die only empirical result seemed to be a possible increase in ozone. During die year 1980, satellite data was used to confirm that die results of die many ground-based ozone monitoring stations were globally representative, diat no geographical bias was caused by the distribution of the stations throughout die world. But perhaps even more important, the complex technique of "ozone trend analysis" was developed. The technique involves die mathematical removal of all known natural variations in ozone concentrations using computers. After diis, if the remaining ozone averages were changing from year to year, this would be due to man's activities, such as die production and emission of CFCs, or to hidierto unrecognized natural variations. The results of Reisel and Tiao at die University of Wisconsin, for instance, have shown diat during die 1970s die most likely trend in ozone was an 0.8% increase globally. The calculated 95% confidence limit of diis result is ±1.3% for the decade. In other words, it was very likely diat die ozone inventory in die 1970s changed from die initial value to a range of from 2.1% upward to 0.5% downward. When compared widi die 1979 computer model results showing a range of from 0.6 to 3.6% downward (widi a reduction of 2.1 % being considered most probable), it is clear diat die best empirical results obtainable are inconsistant widi those obtained by the theoretical models in 1979. However, widi the much-reduced 1981 calculations, one can only conclude that models and actual observations are not necessarily inconsistant and that further work to refine calculations and ozone trend analysis techniques is necessary. In 1981 the technique of ozone trend analysis had developed to the point where a change of about ±1.3% in ozone averages could be detected. In subsequent years, with additional ozone measurements, die sensitivity and confidence of ozone trend analysis is expected to increase. During die 1970s the cumulative Figure 3. Total Ozone Over the Northern Hemisphere
Aerosol Propellents 317 Free World production of P-ll grew to 7.7 billion pounds (3.5 million metric tons) and P-12 increased to 11.2 billion pounds (5.0 million metric tons). These figures show an overall CFC inventory increase of 57%, discounting sinks. Regulatory Activities Almost immediately after the Rowland and Molina theory was promulgated in Nature and various other periodicals in 1974, the press and consumer groups applied pressure on Washington, D.C. to eliminate any further production of chlorofluorocarbons, especially for aerosol uses. Within several months a preliminary assessment was reported by the President's Council on Environmental Quality, which became known as the IMOS document. It cited the issue as a legitimate cause for concern, and that if the National Academy of Science confirmed the theory and predictions, then uses of P-ll and P-12 should probably be restricted to the recharging of existing refrigeration and air conditioning equipment. New fluids would have to be developed for essentially all other then current uses of CFCs. The National Academy of Science first assessment was issued in September 1976 and acted to condemn the CFCs, based upon what was then known and conjectured. The report by their Panel on Atmospheric Chemistry suggested that ozone would be depleted slowly at about 0.07% per year, to a calculated 7% steady state reduced level in 100 to 200 years. However, the data was so uncertain that the probable range of final depletion could only be established within a range of from 2 to 20%. The second NAS report was provided by their Committee on Impacts of Stratospheric Change, sometimes called the Tukey Report. It suggested a moratorium of not more than two years be set up for the establishment of further test data, after which, in the absence of evidence to show that ozone levels would be reduced by no more than a few percent, various forms of restrictions on CFC uses should follow. While noting that such sanctions were a political matter, the report stated that aerosols were a major source of CFC release and that ozone depletion was a global concern requiring international attention. Other areas covered environmental concerns, such as skin cancers, climatological effects and so forth. Under the Federal Clean Air Act Ammendments, the Toxic Substances Control Act and other legislation it became apparent that three Executive federal agencies: EPA, CPSC and FDA had ultimate jurisdiction in regulating the CFC problem. Of these, the EPA had very broad authority over not only aerosols but all other uses of CFCs. It therefore became the lead agency. During 1977 the CPSC indicated they would leave most future CFC decisions to the EPA and FDA. After assessing the NAS reports and hearing other testimony, the EPA and FDA proposed a phase-out schedule for CFCs in aerosols, except for a few special medical items and other justifiable products. Under the regulations no CFC aerosols could be shipped interstate after April 15, 1979, unless exempted. (See Table IV page 320.) The EPA officials then attempted to export their policies to the rest of the Free World. In 1978, for instance, only 39% of the world production of CFCs was made in the U.S.A., with practically all of it going into non-aerosol applications, such as refrigeration, air- conditioning, solvents, flexible polyurethane foam, rigid foams, sterilization mixtures, fire extinguishers and fast-freezing. Canada rapidly passed regulations eliminating CFC propellents from certain toiletries, such as underarm products and hair spray aerosols. Since about 82 % of CFC aerosol usage in both the U.S.A. and Canada had gone into cosmetic and toiletry products, the Canadian decision was very effective in limiting the further use of CFCs in aerosols. (Solvent- based applications of P-ll are still permitted in Canada, for all aerosol products.) Meanwhile in Europe the nine-country bloc eventually reacted by asking for a voluntary 30% reduction in aerosol CFC uses (based on 1976 levels) by the end of 1981. This was accomplished with only moderate pain, and the Ministers are now recommending a voluntary "freeze" for the future at the end of 1981 level. But in the interim, a number of specific countries have become concerned over the highly publicized dire predictions of the EPA and consumer groups. They have now either enacted or are considering legislation which would restrict aerosol uses of CFCs on a unilateral basis. Norway and Sweden adopted virtual bans in 1980 and 1981, respectively. Denmark may ban propellent uses of CFCs during about 1983, or else slowly snuff them out by about 1986 to 1988. Switzerland is seeking regulatory authority to propose a propellent ban, if further reassuring data is not developed by about the beginning of 1983. In Portugal an investigation into the CFC/aerosol situation is in progress, with the industry hoping to avoid a ban. And in Austria, a CFC aerosol ban may be enacted if feasible alternatives become available locally. Japan and Latin American countries
318 The Aerosol Handbook have not taken positions, altiiough Japan may well go the way of Europe if CFC aerosol bans on that continent become widespread. One of me current Japanese problems involves a long-standing law tiiat forbids die use of any flammable propellents in cosmetic aerosol products. This law is now being challenged by firms wishing to sell dimetiiyl etiier (DME) and other propellents in this important marketing area. The effect of die U.S.A. regulations was to reduce die use of CFCs in aerosols from a peak of approximately 500 million pounds (230,000 metric tons) in 1973 to about 14 million pounds (6,300 metric tons) in 1981. Furthermore, die size of die aerosol industry itself was reduced by over 35 % in die process. While diis half billion pound (225,000 metric ton) reduction was significant, representing about a quarter of die world production figures for each of die years 1973 tiirough 1976, the EPA noted that tiiey would be unable to meet their goal of 5% maximum ozone reduction, based upon die National Academy of Science (NAS) figures. They also noted a slow domestic growth in die use of CFCs for non-aerosol applications: from about 370 million pounds (180,000 metric tons) in 1973 to some 550 Table million pounds (250,000 metric tons) in 1979. Faced witii only slight success in Europe, and total frustration in Latin America, Africa and Asia, die EPA again turned tiieir attack on American industry, tiiis time to die non-aerosol CFC applications. See Table III. On October 7, 1980, the EPA issued an Advance Notice of Proposed Rulemaking (ANPR) on CFCs. They started witii the premise that the 1979 NAS figure of a 16.5% ozone depletion at sustained 1977 production levels was still valid. Also, that the world production of CFCs would grow at 9% (and the U.S.A. production by 7%) during the decade of the 1980s unless somehow stifled by regulations, thus, theoretically increasing ozone depletion into die 35 to 60% range. The agency then proposed placing a cap on domestic CFC productions, for instance at the 1979 level. Then, as one scenario, choke off even this much by instituting 25% reductions in both 1983 and 1988. To handle the relationship to ozone depletion, instead of pounds of CFCs they introduced the concept of the "permit pound". The greatest potential ozone depleter on a weight basis was correctly identified as P-ll, and a permit pound of any other CFC was III Production and Uses of P-ll and P-12 Year World Production* (Kilotonnes**) P-ll P-12 World Production* (Pounds X 10s) P-ll & P-12 U.S.A. Production (Pounds x 106) Total Aerosol 1935 1940 1945 1950 1960 1965 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 0 0 1 52 123 235 256 303 342 377 310 330 315 296 0 1 7 98 190 324 340 385 440 452 410 428 412 359 0 2 17 331 690 1230 1314 1516 1724 1827 1587 1671 1602 1444*** 0 2 16 720 755 797 822 861 782 647 615 560 551 0 0 10 38 420 398 440 446 408 326 142 68 18 15 14 'Excludes the small increment from the Communist Bloc States, e.g. 11%. **One kilotonne (metric ton) is 1000 kg or 2,204,000 pounds. •"About 50% of the 1978, 1979 and 1980 totals consisted of aerosols. In 1979 U.S.A. CFC sales were valued at $375 million; with world sales at $1.00 billion. In 1981 U.S.A. CFC sales were valued at $505 million, due mostly to price increases. In 1980 and 1981 the EPA forecasted a 9% worldwide annual increase in CFC production, also quoting a worldwide production figure of 1,927 million pounds in 1977, which undoubtedly included the contribution of the Communist Bloc States.
Aerosol Propellents 319 defined as the number of actual pounds of that substance calculated to be capable of equaling the depletion effect of one pound of P-11. The agency then proposed to stipulate the maximum permissible annual CFC production in terms of permit pounds and allocate permits by some method, for instance by holding auctions. If CFCs should have to be further regulated, the permit pound is a logical concept. The EPA recognized that some CFCs would be less likely to survive in the troposphere, and thus would be less likely to harm the ozone layer. An important key to this is the relative rate of their reaction widi tropospheric hydroxyl radical. For instance, in the case of P-22 the reaction: CHC1F2 + HO - H20 + CC1F2 acts to produce water and chlorodifluorocarbon radical much faster than the corresponding reaction of P-ll with hydroxyl, which is so slow as to be currently unmeasurable. In addition, P-22 has only one chlorine atom that can be stripped off by stratospheric photolysis, whereas P-ll has diree. Using diese and odier considerations scientists at E.I. du Pont de Nemours & Co. have calculated that P-ll poses about 34 times the ozone depletion potential of P-22. Thus, die equivalent of one permit pound (a pound of P-ll) would be 34 pounds of P-22. Table IV provides the relationship of real pounds and permit pounds for the six most important CFCs. Similar information is presented for two chlorocarbons that the EPA will most likely also evaluate in this connection. The permit pound results published by die EPA are acknowledged now to be in error, since all the CCI3F CC12F2 CC1F2.CC12F CC1F2.CC1F2 CC1F2.CF3 CHC1F2 CH2CI2 v-»l"l3.v-'V-'l3 *Rate Constant K (at 265°K), as cm3-molecule~' sec"1. **Later shown to be incorrect; not all relevant factors considered. ***The reciprocal of relative ozone depletion against P-ll. (Sanders, P.A. - 1979). relevant factors were not included during their development. An alternative to auctioning permit pounds might be to tax permit pounds, with the EPA planning figures unofficially estimated as ranging from 25<t initially to 65c by 1990. This would pose a disastrous burden for die small businessman, who could not afford to invest in costly recycling or other conservation equipment. The EPA proposal also ignores the beneficial aspects of CFCs, such as non-flammability, good performance and good economics. A Battelle Institute report, prepared for du Pont and submitted to the EPA, stated mat die energy penalty associated with a ban on certain specified CFC uses would total die equivalent of as much as 50 billion gallons (190 billion liters) of fuel during the first decade the ban was effective, assuming alternatives such as ammonia were substituted. If P-22 were considered as the alternative, the difference would be about 28 billion gallons (106 billion liters) of fuel. For a benchmark, 9 billion gallons (34 billion liters) of fuel per year is equivalent to die energy output of 29 nuclear power plants for one year. As one of dieir efforts to control the misdirected enthusiasm of the EPA, the business community has formed die Alliance for Responsible CFC Policy, which had over 500 members in 1981. With the alliance's support, Congress is now dealing directly with the CFC issue. Bills to amend die Clean Air Act and provide for more research on the ozone layer and stratosphere in general have been introduced by Sen. Lloyd Bentson (D. Tex.) as S.517, and by Rep. Thomas A. Luken (D. Ohio) as H.R. 1853. These were incorporated more recently into H.R. 5252. Table IV Relative Ozone Depletion of CFCs and Certain Chlorocarbons CFC Calculated HO Calculated Number of Real Number Chemical Name Reaction Rate* Pounds per Permit Pound EPA Data* * Du Pont Data P-ll P-12 P-113 P-114 P-115 P-22 — Trichloromonofluoromethane Dichlorodifluoromethane Trichlorotrifluoroethane sym.Dichlorotetrafluoroethane Monochloropentafluoroethane Monochlorodifluoromethane Methylene Chloride 1,1,1 -Trichloroethane <4xl0-'« <5xl0-'« <5xl0"16 < 7 x 10"16 6 x lO"16 24 x 10-16 870 x 10"16 150 x 10"16 1.00 1.27 1.30 2.04 5.00 5.56 — 1.00 1.00 1.22 1.64 2.86 34.00 (330.) (50.) Formila
320 The Aerosol Handbook It is hoped that the results of this work, when added to research already done (du Pont alone has spent over $30 million to date) will ensure that the EPA considers only the most recent scientific developments and seeks a rational international concensus. To its credit, the EPA in 1981 has repeatedly emphasized diat die agency has made no decision on whether further regulation of Table V U.S.A. Exemptions From the Bans on Chlorqfluorocarbon Propellents 1. Aerosol propellents, when not used to expel liquid or solid materials different from the propellent; e.g. CFC refrigeration or aid conditioning system refills, boat horns, fire extinguishers and so forth. 2. Mercaptan (thiol) stench warning devices for use in mines. 3. Release agents for molds used in the production of plastic and elastomeric materials. 4. Flying insect pesticides for use in non-residential food- handling areas and for space-spraying of aircraft. 5. Diamond-grit spray. 6. Non-consumer articles used as cleaner-solvents, lubricants or coatings for electrical or electronic equipment. 7. Articles necessary for the safe maintenance and operation of aircraft. 8. Uses essential to the military preparedness of the U.S.A. as determined by the EPA Administrator and the Secretary of Defense. 9. Metered-dose steroid human drugs for nasal or oral inhalation, 10. Metered-dose adrenergic bronchodilator human drugs for oral inhalation. 11. Contraceptive vaginal foams for human use. 12. Metered-dose ergotamine tartrate drug products administered by oral inhalation for human use. 13. Use of P-115 (chloropentafluoroethane) alone or with carbon dioxide, nitrous oxide, propane, and octafluorocyclobutane as an aerating agent for sprayed or foamed food products, with any propellent effect being incidental to and no more than is minimally necessary to achieve the aerating function, except that use is not permitted for those standardized foods that do not provide for such use. 14. Other temporary or permanent exemptions as may be approved from time to time, such as a blowing agent for polyurethane foams and a unique insect spray for tobacco barns. Note: In a Final Rule (40 FR 55241, Nov. 27, 1978) aerosol propellents were clarified to positively include those substances such as P-ll and P-l 13, which have no gauge pressure at 75°F (23.9°C) or less. CFCs is warranted, will submit future technical reports, for instance, from NAS, to careful peer review, will evaluate competent cost/benefit studies, and seek an international concensus on what further steps, if any, are needed. During the opening months of 1982, as diis is being written, the EPA has continued their 1981 stance. They are evaluating the huge industry response to dieir ANPR of October, 1980 and consulting with industry, scientific institutions and Congress in an effort to develop long-term and more rational strategies for die regulation of CFCs. Only slight and often temporary relaxations have been made by eidier the EPA or FDA in permitting die utilization of saturated CFCs in aerosol products. As of 1982 the listing shown in Table V represents just about all the sanctioned aerosol uses for these propellents. Costs of Conversion to Alternate Propellents In 1975, almost 50% of die 2.7 billion aerosols produced in die U.S.A. contained a saturated CFC propellent or solvent, and die production of diese fluids (for both aerosols and odier uses) amounted to almost 800 million pounds (360,000 metric tons). Six domestic firms synthesized CFCs, and dieir shares of die aerosol propellent market in diat year were about 39% du Pont (Freon), 39% Allied Chemical (Genetron), 11 % Penn- walt (Isotron), 6% Union Carbide (Ucon), 4% Kaiser Chemical (Kaiser) and 1 % Racon (Racon). About 326 million pounds (150,000 metric tons) of CFCs were used in aerosols, contrasted with about 180 million pounds (82,000 metric tons) of hydrocarbons and much smaller amounts of CO2 and other propellents. By 1981 diis picture had changed radically. CFC production for aerosol uses had dwindled to almost nothing. Some firms, such as Union Carbide, dropped out. Hydrocarbon gases were now the major aerosol propellents, with about 300 million pounds (136,000 metric tons) of Aerosol Grade and Commercial Grade n-butane, isobutane and propane (and their blends) being used during the year. Over 90% of all U.S.A. aerosols now used hydrocarbon propellents. During die late 1970s du Pont and other producers looked for CFCs that would be marginally less stable in the troposphere than P-ll and kindred compounds, yet not so unstable that they would contribute to smog formation, as does trichloroethylene. Many hydrogen- containing CFCs were found to have this desired intermediate stability. In addition, the true fluorocarbons
Aerosol Propellents 321 (which do not contain chlorine) were found to be acceptable from the standpoint that they do not contribute to any known ozone depletion mechanisms. Some fourteen initial compounds were singled out as candidates and all of them contained hydrogen in the molecule. They are included in a rather comprehensive listing provided in Table VI. The most promising are P-22, P-142b and P-152a, although admittedly die last two are still somewhat flammable. Despite some very preliminary evidence diat P-22 and P-142b might be very weak mutagens, comprehensive studies covering die toxicological profile of diese fluids should be completed in 1982 and die data dius far looks extremely encouraging. P-152a has now been fully cleared. A full profile of acute, sub-chronic and chronic toxicological tests now costs several million dollars and can take up to about four years to complete. Because of its relatively low price and desirable properties, it looks like P-22 will become the workhorse of the U.S.A. CFC industry, particularly if die Rowland Table VI The Commercial Properties of Major Chlorqflnorocarbons and Alternative Compounds CFC Number 11 12 13 14 21 22 23 31 32 113 114 115 116 123 124 125 132b 133a 134a 141b 142b 143a 152a 3110 C-318 — Formula CC13F CC12F2 CCIF3 CF, CHCbF CHC1F2 CHF3 CH2C1F CH2F2 CC12F.CC1F2 CC1F2-CCIF2 CC1F2.CF3 CF3CF3 CHC12.CF3 CHCIF.CF3 CHF2.CF3 CH2C1-CC1F2 CH2C1CF3 CH2F.CF3 CH3CC12F CH3CC1F2 CrT3'CrlF3 CH3-CHF2 C4F10 C4F8 (CHF2)20 (CF3)20 (CH3)2Q H-1301 CBrF3 H-1211 CBrClF2 (LP Gases) C3H8) etc. Boiling ] °F 75 -22 -115 -198- 48 -41 -116 16 -61 118 39 -38 -164- 82 12 -55 116 45 -16 90 14 -54 -13 28 22 28 -67 -13 -72 28 Point °C 24 -30 -82 128 9 -40 -83 9 -52 48 4 -39 109 28 -11 -48 47 7 -27 32 -10 -48 -25 -2 -6 -2 -55 -25 -58 -2 Toxicology Low Low Low Low Toxic Poss.v.wk.mutagen Low Toxic Low Low Low Low Low Low Low Assumed low Very incomplete Embryotoxic Very incomplete Weak mutagen Very weak mutagen Incomplete Low Low Low Very incomplete Very Incomplete Low Low Low Low Comm. Mfg. Flammability Process None None None None None None None Yes Yes None None None None None None None None None None Slight Slight Moderate Moderate None None None None Yes None None Yes! Excellent Excellent Good Fair Fair Excellent Fair None None Excellent Excellent Good Fair None None None None None (USA) None Developmental Good None Excellent Discontinued Fair Discontinued Discontinued Very Good Very Good Very Good Excellent Worldwide Present or Potential Significant Commercial Applications Aerosol Refrig./A-c. Blowing AG. Excellent* Excellent* None None None Good None Fair None Good* Excellent* Good* None None None None None None (USA) None None Good None Very Good Fair Fair Fair Fair Excellent Specialized Specialized Excellent Excellent Excellent Good Fair Excellent Fair None None Good Excellent Good Fair None Fair Fair None None None None Fair Fair Good Good Poor Specialized Specialized None Excellent Excellent None None Good None None Good Excellent Good None Fair Slight None Poor Fair Fair Good Good None Good None None None None None None List Price (Dec-1981) */Lb. */Kg 0.64 0.74 11.00c 18.62c 1.14 13.46c 0.79 1.02 2.55-c 4.90c — — 1.75c 1.55 11.00" 12.00" 0.57 3.50= 2.00c 0.22 1.41 1.63 24.30c 41.06c 2.51 29.68c — 1.74 2.25 5.62'c 10.80c — 3.86c 3.42 24.00cc 26.00" 1.26 7.72c 4.40c 0.48 •Banned in the U.S.A. for aerosols and partly banned or reduced in other countries. CFC-11 and 12 banned in Norway and Sweden. Prices are for bulk (f.o.b.) unless noted by "c" = small cylinders (80 pound average net) or "tc" =ton cylinders, "e" represents an estimated price. Some data may be slightly misleading due to brevity and those interested should pursue the available literature for more precise information.
322 The Aerosol Handbook and Molina theory continues to be sustained by the EPA for a number of additional years. Plant expansions have to be made to handle increased requirements. For instance, Allied Chemical added 25% capacity in 1980, and began a $50 million HF expansion at Geismar, LA in that same year. As of the beginning of 1982, P-22 had not been used in any aerosol productions. The use of P-142b (Penn- walt) was vanishingly small, due to the unresolved tox- icological situation and other things, and the utilization of P-152a was significant but very small. It may have been included in up to 1 % of U.S.A. aerosols. Outside the U.S.A. it probably was unobtainable. A very major consideration in formulating aerosols is (of course) the cost of ingredients. Since the alternate fluorocarbon propellents cost between 5 to 8 times as much as the hydrocarbons, they must provide some special attribute to the product besides the simple propellent function in order to be used. The non- flammability factor, which applies only to P-22, is normally unimportant, since the other major ingredients of the formula, such as alcohols, petroleum distillates and the like, are flammable, thus making the total composition flammable. Borderline exceptions to this generalization can be made in the case of 1,1,1-trichloro- ethane, or for blends of methylene chloride and 1,1,1-trichloroethane, when they are used in large percentages. The alternate fluorocarbons do show far better solvency than the hydrocarbon propellents, which accounts for some of their uses. As dimethyl ether becomes more thoroughly tested, it may act to replace propellents such as P-152a, since it is a superb solvent and much less costly. Aside from research and manufacturing costs to develop alternate propellents, the industry had to develop and test literally thousands of new' 'non-CFC'' aerosol products. Of the approximately 65,000 aerosol formulas on the market in 1975, about 30,000 had to be reformulated due to the regulatory ban in the U.S.A. An additional 10,000 have been reformulated in Canada and Europe, and this process is continuing. Much of this work can be classed as duplicative, with one new formula generalization specifically being applied to a number of products. When it is considered that the costs are not merely those of reformulation, but include toxicological testing, efficacy testing, field testing and possible EPA re-registrations, the cost can be viewed as extremely high. The cost of the laboratory work alone has been estimated at about $340 million. The work occupied the full time resources of virtually every aerosol laboratory in the U.S.A. for almost three years. During this time research in all other directions was terminated, and the industry suffered many opportunities foregone, due to the EPA and FDA bans. It is impossible to measure the ultimate cost of this backslide. Production costs increased, mainly due to the need to more safely handle hydrocarbons since these propellents were the principal heirs to the CFCs and were almost doubling in rate of use. There are an estimated 550 filling lines in the U.S.A., ranging in production speeds from about 10 to 380 cpm. In 1973 about 25% of these lines were "more or less" equipped to produce hydrocarbon-type aerosols. Depending upon the funds available to the filler and his commitment to safety, amounts of between $10,000 to $700,000 (in 1978 dollars) were spent for each line upgraded. The larger marketers and fillers, with larger production facilities, generally spent the higher amounts, from $175,000 to $700,000 per line. A rough calculation suggests that the purchase and installation of both improved and new safety equipment cost the aerosol industry about $55 million (in 1978 dollars). The figure is about one-third of the "state of the art" cost and reflects the limited capital most fillers had after the aerosol business dwindled by about 35 % in the U. S. A., in the aftermath of the Rowland and Molina theory and the bad press that came with it. The "missing" two-thirds of a full commitment to safety is possibly evidenced by the procession of fires and explosions that has occured in filling plants during the last several years. When the costs of reformulation, toxicological testing, consumer testing, new formula market introduction, safety engineering, new equipment, public relations programs, ozone studies, fires and so forth are fully considered, the penalty of the CFC ban in the U.S.A. amounts to an estimated $1.0 to $1.2 billion in 1982 dollars. The impact of industry shrinkage (plant closings, consolidations, etc.) has not been included, nor has the upstream effect upon suppliers of precursor chemicals and component parts. This huge cost has, as always, been passed along to the ultimate consumer. Considering the production during the period of 1975 through 1981, it would amount to an increment of about 7.5c per average can. Outside the U.S.A. industry costs for conversion have been substantially less. In Canada, where CFCs are imported and many formulations now use alternate
Aerosol Propellents 323 propellent technology developed in die U.S.A. under die regulatory sword, die cost of dieir partial ban on CFCs has been estimated at about 1% of die U.S.A. total. In Europe, die EEC countries are typified by die U.K. which went from 95 million pounds (43,000 metric tons) of CFCs in 1977 to an estimated 66 million pounds (30,000 metric tons) in 1982. Production volumes in bodi years were about equal. The loss was compensated by an increase in hydrocarbon usage: from 28 million pounds (12,900 metric tons) to an estimated 38 million pounds (17,000 metric tons). Relatively little pain was caused by diis voluntary transition, since die time frame was generous, diere was little bad press, and die bulk of die change was handled by the top 20 or so of die 126 contract and marketer fillers. Nearly all of diem already had hydrocarbon facilities, at least to some degree. In Norway and Sweden, which now have CFC bans, die process of change was very costly, forcing many smaller firms to go out of business and inviting a huge increase in imports from nearby Denmark and Germany. At diis time, no large aerosol-producing country appears in danger of a ban, and diere is hope diat die CFC/ozone dieories may be so strongly modified by new data during die next two or diree years diat no further political interdictions or bans will take place. Properties of the CFC and FC Propellents Because of the current ban on saturated CFC propellents in die U.S.A. only minor coverage will be accorded to P-ll, P-12, P-113, P-114 and P-115. The first four are still very important outside die U.S.A., where they were estimated to account for about 480 million pounds (218,000 metric tons) of CFC production in 1980. The forerunner of die line is P-12, followed by P-ll and dien (far behind) P-114. Only P-12 and P-l 14 can be considerred as true propellents. P-ll and P-113 are incapable of forming a spray at room temperatures and are commonly thought of as volatile non-flammable solvents. P-12 is used most commonly at levels between 20 to 50% of die total formula. At 20% the spray is fairly coarse, and light-bodied volatile concentrates are required to get a satisfactory spray down to die end of die can. Such solvents include 1,1,1-trichloroediane, edianol and isopropanol. If a less volatile concentrate is required, dien the minimum level of P-12 will have to be raised to about 25%. Where the concentration of P-12 is relatively small die distillation effect must be considered. As die dispenser is sprayed, die outage space expands and P-12 vaporizes out of die liquid phase to maintain die equilibrium pressure. The result is a gradual reduction of the per cent P-12 in die liquid phase, becoming more serious near die end of the can since diere is less of a reservoir to draw upon. The pressure and delivery rate can be expected to decrease at least slightly as any aerosol is used up, but die effect is more pronounced for products containing low percentages of propellent. The properties of P-12 are shown in Table VII (Page 324) along widi diose of odier common CFCs. Succinctly stated, it has a vapor pressure diat can be tolerated at any concentration (aldiough a "DOT Specification 2P" or' 'DOT Specification 2Q_'' can may be needed at levels of over about 70%), it is non-flammable, non- hydrolysable and a radier poor solvent. On die basis of economics, and perhaps bans or odier sanctions, products which used to have 20 to 25% P-12 as die propellent have now been reformulated to contain 3 to 5% CO2. The spray may be a little coarser, particularly as die package is sprayed down, and perhaps somewhat more sensitive to propellent leakage rates, but odierwise diere are very few problems widi die transition. Products such as disinfectant/deodorants, wasp and hornet sprays, modiproofers, engine degreasers, carburetor and choke cleaners, bug killers and so forth may be sprayed widi eidier propellent. The early hair spray formulations typically contained 35% edianol-based concentrate, plus 65% of a propellent blend consisting of about 20 parts P-12 and 45 parts P-ll. The large percentage of CFCs were used to give elegant sprays (with die valves then available) and only a slight degree of flammability, such as an 8 inch (200 mm) flame in die Flame Projection Tester. However, in die U.S.A. at least, edianol was only about half as costly as the CFCs, and this economic fact forced CFC levels inexorably downward, until by about 1968 hair spray formulas averaged about 50% concentrate, 26% P-12, 14% P-ll and 10% isobutane A31. The flame projection was now in the 16 to 18 inch (400 to 457 mm) range. During diese transitions to less costly, more flammable products, die industry closely monitored die market to see if diere were any hazardous consequences. Essentially none were reported. In 1975 through 1977, when the CFCs had to be removed from most U.S.A. aerosols, diese data encouraged most marketers to go directly to edianol/hydrocarbon formulations. A few more cautious ones tried to use CO2, Next Page
Aerosol Propellents Previous Page propellent technology developed in die U.S.A. under die regulatory sword, the cost of dieir partial ban on CFCs has been estimated at about 1% of the U.S.A. total. In Europe, die EEC countries are typified by die U.K. which went from 95 million pounds (43,000 metric tons) of CFCs in 1977 to an estimated 66 million pounds (30,000 metric tons) in 1982. Production volumes in bodi years were about equal. The loss was compensated by an increase in hydrocarbon usage: from 28 million pounds (12,900 metric tons) to an estimated 38 million pounds (17,000 metric tons). Relatively little pain was caused by uiis voluntary transition, since die time frame was generous, uiere was little bad press, and die bulk of die change was handled by the top 20 or so of the 126 contract and marketer fillers. Nearly all of diem already had hydrocarbon facilities, at least to some degree. In Norway and Sweden, which now have CFC bans, die process of change was very costly, forcing many smaller firms to go out of business and inviting a huge increase in imports from nearby Denmark and Germany. At uiis time, no large aerosol-producing country appears in danger of a ban, and uiere is hope mat die CFC/ozone dieories may be so strongly modified by new data during die next two or diree years mat no further political interdictions or bans will take place. Properties of the CFC and FC Propellents Because of the current ban on saturated CFC propellents in die U.S.A. only minor coverage will be accorded to P-ll, P-12, P-113, P-114 and P-115. The first four are still very important outside die U.S.A., where they were estimated to account for about 480 million pounds (218,000 metric tons) of CFC production in 1980. The forerunner of die line is P-12, followed by P-ll and dien (far behind) P-114. Only P-12 and P-l 14 can be considerred as true propellents. P-ll and P-113 are incapable of forming a spray at room temperatures and are commonly thought of as volatile non-flammable solvents. P-12 is used most commonly at levels between 20 to 50% of die total formula. At 20% the spray is fairly coarse, and light-bodied volatile concentrates are required to get a satisfactory spray down to die end of die can. Such solvents include 1,1,1-trichloroeuiane, euianol and isopropanol. If a less volatile concentrate is required, dien the minimum level of P-12 will have to be raised to about 25%. Where the concentration of P-12 is relatively small die distillation effect must be 323 considered. As die dispenser is sprayed, the outage space expands and P-12 vaporizes out of the liquid phase to maintain die equilibrium pressure. The result is a gradual reduction of the per cent P-12 in die liquid phase, becoming more serious near die end of the can since uiere is less of a reservoir to draw upon. The pressure and delivery rate can be expected to decrease at least slightly as any aerosol is used up, but die effect is more pronounced for products containing low percentages of propellent. The properties of P-12 are shown in Table VII (Page 324) along widi uiose of ouier common CFCs. Succinctly stated, it has a vapor pressure diat can be tolerated at any concentration (aluiough a "DOT Specification 2P" or' 'DOT Specification 2Q_'' can may be needed at levels of over about 70%), it is non-flammable, non- hydrolysable and a rauier poor solvent. On die basis of economics, and perhaps bans or ouier sanctions, products which used to have 20 to 25% P-12 as die propellent have now been reformulated to contain 3 to 5% CO2. The spray may be a little coarser, particularly as die package is sprayed down, and perhaps somewhat more sensitive to propellent leakage rates, but ouierwise uiere are very few problems widi die transition. Products such as disinfectant/deodorants, wasp and hornet sprays, mouiproofers, engine degreasers, carburetor and choke cleaners, bug killers and so forth may be sprayed widi eiuier propellent. The early hair spray formulations typically contained 35% euianol-based concentrate, plus 65% of a propellent blend consisting of about 20 parts P-12 and 45 parts P-ll. The large percentage of CFCs were used to give elegant sprays (with die valves then available) and only a slight degree of flammability, such as an 8 inch (200 mm) flame in die Flame Projection Tester. However, in die U.S.A. at least, euianol was only about half as costly as die CFCs, and this economic fact forced CFC levels inexorably downward, until by about 1968 hair spray formulas averaged about 50% concentrate, 26% P-12, 14% P-ll and 10% isobutane A31. The flame projection was now in the 16 to 18 inch (400 to 457 mm) range. During diese transitions to less costly, more flammable products, die industry closely monitored die market to see if diere were any hazardous consequences. Essentially none were reported. In 1975 through 1977, when the CFCs had to be removed from most U.S.A. aerosols, diese data encouraged most marketers to go directly to edianol/hydrocarbon formulations. A few more cautious ones tried to use CO2,
324 The Aerosol Handbook but even when up to 20% methylene chloride was included the sprays were still considered too coarse. One very promising formula, using 60% concentrate, 15% methylene chloride, 14% isopentane and 6% CO2 was abandoned after about 500,000 cans had been made, due to manufacturing hazards involving the isopentane, plus the unreliable supply situation for that ingredient. The U.S.A. is rather unique in having unlimited supplies of specially denatured ethanol (95v% and anhydrous) at prices of about $0.30/lb. ($0.66/kg) on a 1981 and 1982 basis. In the past this has acted to depress the per cent of the relatively expensive CFCs in hair sprays, personal deodorants and other ethanol- based products. But now, since it is 50% more expensive than the Aerosol Grade hydrocarbons, there is at least some incentive to increase the amount of propellent. The cost of ethanol in virtually all other countries is much more than either the CFCs or hydrocarbon gases. Thus, hair sprays and other ethanol formulas are designed with a minimum of this alcohol. In Mexico, hair sprays have been sold with as little as 12% ethanol and the balance mainly CFCs. In various European countries, a heavy tax is applied to ethanol (also sometimes to isopropanol), with extreme conservation as the end result. The pressure and densities of various P-12/P-11 blends with anhydrous ethanol are given as Figure 4 and Figure 5 respectively. The pressure data was developed using a refrigeration filling technique (now obsolete for production purposes in nearly all countries), simply as a means of excluding the partial pressure of air that always enters into the total pressure of pressure-filled aerosol products. When the percentage of P-12 reaches about 40% to 96%, the products give a finely particled spray pattern, progressing to the area of a 3/*m average particle size at the 90% level. For particularly good break-up and soft, slow delivery rate sprays, valves with vapor-tap orifices are often used. The chilling or cooling effect is also reduced, and this has been important in such products Table VII Physical Properties of Chlorofluorinated and Fluorinated Hydrocarbon Propellents (Common Types) p-11 p-12 p-21 p-22 P-113 P-114 P-115 P-152a P-142b Formula Molecular Weight CCI3F CCI2F2 CHCI2F CHC1F2 CC12FCC1F2 CC1F2CC1F2 137.4 120.9 102.9 86.5 187.4 170.9 CC1F2CF3 CH3CHF2CH3CC1F2 154.4 66.1 100.5 Boiling Point °F) Freezing Point (°F) Pressure (psi-g. at 70°F) Pressure (psi-g. at 130°F) Density (gm./ml. at 70°F) Density (gm./ml. at 130°F) Vapor Density at B.P. (gm./l. Water Solubility (ml./lOO gr.)* Kauri-Butanol Number Solubility Parameter Hydrolysis in Water (gm./yr.)" Hydrolysis in 1 % Na2C03 (gm./yr.)" Hydrolysis in Water with Steel Strips Present (gm./yr.)** Flammability Limits in Air v% 74.8 -168. -1.3 24.3 1.485 1.403 5.861 20. 60. 7.5 0.005 01.20 19. none 21.6 -252. 70.2 181.0 1.325 1.191 6.258 5.7 18. 6.5 0.005 0.040 0.82 none 48.1 -211. 8.4 50.5 1.323 1.193 4.570 226. 102. 8.0 0.010 330 5.2 none -41.4 -256. 122.5 300. 1.209 1.064 4.827 85. 25. 6.5 0.010 220 0.14 none 117.6 -31. -9.2 3.4 1.574 1.493 7.330 31. 7.2 0.005 none 38.4 -137. 12.9 58.8 1.468 1.360 7.83 12. 6.2 0.005 0.010 1.4 none -37.7 -159. 104.9 252.1 1.309 1.149 8.781 7.4 7. 5.7 0.005 0.005 0.08 none 11.2 -179. 61.7 176. 0.911 0.813 3.38 116. 11. 7.0 0.005 0.005 0.010 5.1/19.1 15.1 -204. 29.1 92.0 1.119 1.028 4.84 33. 20. 6.8 0.010 0.20 9.0/14.8 *At one atmosphere and 77°F. **VaIues expressed as grams HCl/liter of propellent/year, at 68°F when solutions of approximately 25% Propellent, 25% Water and 50% Isopropanol are stored in ampules.
Aerosol Propellents 325 50 1 30 ^ - - 1 ^ p T —i ~^b^ ^~ -rf— - 1 ' 1 4 | i bi emi >er ati re ' 1 1 j i 1 hrrr k(l°F 1 rz i 1 i " Curve A: Curve B: — Curve C: Curve D: C *ur ve E: XiLJjJifl \- ! ]__ ^ — — — — P-12/11 (50:50) P-12/11 (45:55) P-12/11 (40:60)- P-12/11 (35:65) P -12/11 (30:70) 40 50 60 70 %-PROPELLENT BLEND 80 90 Figure 4. Pressure of CFC-11/12 Mixtures with Ethanol (Air Free) as feminine hygiene sprays where P-12 is usually over 90%. For these products, a second advantage of the vapor-tap is that the dispensers can be sprayed satisfactorily either upright or inverted. P-12 comes close to being an ideal propellent, but a significant drawback has been the fact that it is a poor solvent. This is due to the CF2 moiety in an essentially apolar molecule. Numerous polar materials, such as stearic acid and the other carbolyxic acids, methylene glycol and certain other glycols, certain deodorant chemicals and so forth are essentially insoluble. Some substances are soluble, but have no affinity for the propellent and therefore exert relatively little vapor pressure depressent effect. In formulation of aerosols that contain P-12 as the propellent, it is common to add cosolvents. Methylene chloride, 1,1,1-trichloroethane, P-ll, ethanol, isopropanol, acetone and the intermediate ketones have all been used for this purpose. P-ll has been used in aerosols almost as long as P-12. It may have been used first in 1946 by H.E. Peterson (then at Continental Can Company, Inc., Chicago) when he added it to insecticides of the P-12/ kerosene type to achieve a suitably fine particled spray pattern, while keeping the pressure at or below 25 psig at 70°F (172 pKa at 21.1°C) in order to meet certain interstate commerce regulations in force at that time. 28t 160 1?(1 04( 02( prv 98( 961 94C 92C 90C 86C 8 4C y^^ Tei ipe ra:ur , L e f 7lo0i'. ' 1 | y s\/ c c c 1 A t 7\7 r / i I _+_i ! urve A: urve B: urve C: urve D: 1 i I 1 1 C O 1 1 P-12/11 (30:70) P-12/11 (50:50)- P-12/11 (70:30) P -12 1. 1. 1. 1. 1. 1. 1. 1. 1. - 1. £ 1. d u 2 0. >. 0. is °- \ 0. a 0. 0. 0. 0. °" ""46 45 50 55 6"0 65 70 75 80 85 90 FLUOROCARBON PROPELLENT BLEND (Weight-percent) Figure 5. Density of CFC-11/12 Mixtures with Ethanol When added to P-12 formulas, P-ll also adds solvency and density. Being non-flammable, it reduces the flam- inability of aerosols whenever it replaces a portion of the concentrate. It is commonly purchased as a prepared blend with P-12. A format has developed for the nomenclature of these particular blends; for example a combination of 60% P-12 and 40% P-ll would be stated: P-12/11 (60:40). The "12" always appears first. Unlike P-12, which resists hydrolysis in aqueous solutions or dispersions below about pH 12.5, P-ll is readily hydrolysed under most conditions. At least three unrelated reactions are involved, leading to such products as P-21 (CHCUF), itself unstable in alkaline media, P-112 (CC12F.CC12F), COz, HC1 and HF. It may be stable in acidic or neutral systems if held in glass or plastic. But in aerosol cans, even double lined tinplate variables, the presence of tiny traces of iron, tin and copper is often sufficient to cause a 10,000-fold increase in hydrolytic decomposition rate. By adding about 0.1% nitromethane to the formula, these reactions are almost 100% eliminated. Nitromethane likewise inhibits P-ll hydrolysis in hydroalcoholicsolutions containing at least as high as 98% pure ethanol. In essentially anhydrous alcohol solutions, P-ll can react with the ethanol in a free radical mechanism to produce
326 The Aerosol Handbook Table VIII Amounts of Phosgene (mg) Formed by the Pyrolysis of One Gram of Propellents Temperature °F °C 392 200 572 300 752 400 932 500 1112 600 1292 700 1472 800 1652 900 1832 1000 p-ll Steel 0 0 0 0 0 0.002 0.013 0.21 19. Against Quartz 0 0 0 0 0 0 0 0.07 7.04 P-12 Steel 0 0 0 0 0 0 0.001 0.009 0.13 Against Quartz 0 0 0 0 0 0 0 0 0.002 Methylene Steel 0.007 0.06 1.3 10.4 — — — — — Chloride Against Quartz 0.0005 0.0025 0.0035 0.0440 1.60 9.3 22.0 18. 18. Propellent/air mixtures held about four hours in steel or quartz tubes. Phosgene is a product of only one of several known reactions. Ta'ble IX Pressure of Pure Fluorocarbon Propellents at Various Temperatures Temperature 40°F 50°F 60°F 70°F 80°F 90°F 100°F 110°F 120°F 130°F 140°F 150°F 160°F 170°F 4°C 10°C 16°C 21°C 27°C 32°C 38°C 43 °C 49°C 54°C 60°C 66°C 71°C 77°C P-ll -7.8 -5.9 -3.9 -1.3 1.6 5.0 8.9 13.4 18.5 24.3 30.8 38.2 46.3 55.2 P-12 37.0 46.7 57.7 70.2 84.2 99.8 117.1 136 158 181 207 235 265 297 P-21 -2.2 0.7 4.3 8.6 13.3 19.4 25.7 41.0 61.2 85.0 P-22 68.3 85.4 104.4 123.3 145 168 193 255 340 343 P-113 -12.1 -11.2 -10.4 -9.3 -8.0 -6.1 -4.4 -2.0 0.7 3.7 7.2 11.0 16.1 21.6 P-114 0.5 4.0 8.1 12.9 18.3 24.6 31.7 39.7 48.7 58.8 70.1 82.0 95.3 110.0 P-115 58.3 72.1 88.2 104.9 123.7 143 166 189 216 252 291 335 376 422 Table X Pressure ofP-12/P-ll Blends at Various Temperatures Composition P-12 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% p-ll 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 40°F 4°C 37.0 33.0 29.0 25.0 21.0 16.9 12.6 8.0 2.9 -2.7 -8.7 70°F 21°C 70.2 63.9 57.3 50.8 44.2 37.5 30.5 23.0 15.3 7.1 -1.3 Temperature 100°F 38°C 117 107 97.3 87.3 77.2 67.1 56.8 45.9 34.2 21.9 8.9 130°F 54°C 181 167 151 136 121 107 91.9 76.3 60.1 42.8 24.3 160°F 71°C 265 244 223 202 180 158 137 117 94.6 71.3 46.3 Pressures in Table IX and X are noted in psig. To convert to kPa multiply by 6.895.
Aerosol Propellents 327 P-21 (CHCUF), acetaldehyde (CH3CHO) and HC1. Nitromethane can again function as an effective inhibitor. In commercial products such as hair sprays, alcololysis rarely occurs, but when it does the results are disasterous. The rarity is due to the presence of other ingredients, which either act to destroy traces of peroxide free radical reaction initiators or else exert direct chain-breaking effects of their own. Recognizing the beneficial effects of nitromethane, several CFC manufacturers have offered a blend known as P-11S to interested customers. It consists of a mixture of 99.7% ethanol and 0.3% nitromethane, and is designed to give a 0.1 % level of the inhibitor in the average ethanol- type aerosol product. The "S" stands for stabilized. P-ll should never be used in conjunction with anhydrous ethanol formulations in aluminum cans, since here a curious reaction may occur, producing P-21 (CHCI2F), acetyl chloride (CH3COCI) and H2. The acetyl chloride will promptly ruin the formulation and the nascent hydrogen will rupture the dispenser unless it can penetrate the seal rapidly enough to dissipate before creating intolerable pressures. From time to time the CFCs have been blamed for excessive rusting of steel furnace surfaces. Tests have shown that P-12 does not react with steel or iron below about 1450°F (790°C) and P-ll fails to react below about 1220°F (660°C). These temperatures are readily attained in the combustion area, but not outside this zone. Thus, some rusting of the steel may take place, where it is in contact with the flames, and this rate of oxidation may increase if traces of P-ll or P-12 are present in the furnace air intake, provided it is not supplied from outside the house. A more important consideration is meuiylene chloride, which can attack steel at temperatures at least as low as about 360°F (182°C). Several reactions occur, and products include phosgene (COCb), HC1, HF and C02. The acid fumes attack the steel, forming divalent halides, which are then hydrolytically oxidized to iron (III) oxide, or rust. Rust accumulations on the heated exterior surfaces of the furnace are highly visible and have caused the bulk of field complaints and bad press. The generation of phosgene (COCl2) by pyrolysis of P-ll, P-12 and methylene chloride is shown in Table VIII. When P-ll, P-12 and particularly methylene chloride or 1,1,1 -trichloroethane are burned, such as by the ignition of an aerosol spray, significant quantities of phosgene (COCI2) carbon oxychlorofluoride (COC1F) and related compounds are formed. The phosgene (MAC = 50 ppb) has never proved fatal, but can cause nasal irritation, a burning numbness in the lungs and various stages of diarrhea. The accompanying fumes of HC1 and (particularly) HF cause similar irritations and also attack metal surfaces. For these reasons, flame pro- TableXI Pressure of P-.12/P-114 Blends at Various Temperatures Composition P-12 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% P-114 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 40°F 4°C 37.0 34.2 31.3 28.1 25.1 21.5 17.8 14.1 9.9 5.2 0.5 70°F 21°C 70.2 65.7 61.1 56.1 51.0 45.6 39.9 33.6 27.2 20.2 12.9 Temperature 100°F 38°C 117 110 104 96.3 88.6 80.3 71.8 62.5 52.5 42.2 31.7 130°F 54°C 181 172 162 150 139 127 115 102 87.8 73.6 58.8 160°F 71°C 265 250 236 221 205 187 172 155 136 116 95.3 Pressures are noted in psig. To convert to kPa multiply by 6.895.
328 The Aerosol Handbook 90 80 70 _ 60 u PS 40 D 30 20 10 260 T fifl 7(1 'F 1 ..,J P-12 P-114 10 20 30 40 50 60 70 80 90 100 PERCENT PROPELLENT-1Z Figure 6. Pressure of P-12/Ethanol and P-114 Ethanol Mixtures jection tests, the closed drum test and other combustion type studies should always be conducted in a well ventilated hood. P-114 is the third most commonly used propellent; also one of the more highly fluorinated ones, since it contains 44.4% fluorine. Because of this it exhibits outstanding chemical, hydrolytic and thermal stability, as well as a very low odor level. Its low pressure has made it especially interesting as a propellent for glass aerosols, either straight or blended with P-12. The pressure of various CFC propellents is compared with temperature in Table IX. In addition, since P-12/11 and P-12/114 are blended very commonly to achieve special properties, the pressures of respective blends are shown at various temperatures in Table X and XI, respectively. P-114 is a very poor solvent. About 78.7% P-114 even 95v% ethanol becomes immiscible at 70°F (21.1°C). The corresponding value for P-12 is 91.1%, and for P-l 1 it is 100.0%. The more highly fluorinated CFCs and CFs are even poorer solvents in general. Propellents such as P-l 15 and P-C318 are among the poorest solvents known. P-114 is actually a commercial mixture of about 92% sym, dichlorotetrafluoroethane (CC1F2.CCIF2) and 8 % 1,1 -dichloro-1,2,2,2-tetrafluoroethane (CCI2F.CF3). The second isomer, technically known as P-l 14a, boils only 0.6°F (0.3°C) away from the first and has virtually identical properties. Throughout the world more P-114 is used for cologne and perfume sprays than any other application. A comparison of old and new formulations is shown in Table XII. The hydrocarbon version is used only in the U.S.A., as a result of the CFC ban. When fragrance products are packaged in aluminum tubes instead of glass or coated glass there is no further need to limit pressures, and so formulas much higher in P-12 content are used. The pressure of various P-12, P-114 and anhydrous ethanol compositions is shown in Figure 6. The higher and lower fluorine analogs of P-l 14 are identified as P-l 15 and P-l 13, respectively. Both have been used in aerosol formulations to some extent. P-l 15 is a rather high pressure fluid having poor solubility in both water and alcohol, as well as many oils. It disperses well, and this, coupled with its certification as a food-approved propellent, has led to its major use, as an adjuvant propellent for whipped toppings. By adding it to nitrous oxide or carbon dioxide, using a special system, the mixture can be used as a food propellent for puffed products, giving them more stability in the foamed stage and also allowing the last portion of the dispenser to dispense product that is not overly dense or runny, as would be the case for the compressed gas propellents alone. One interesting application has been for a chocolate ice cream topping. Without P-l 15, at about 1 % of the total formula, the puff of product slowly lost its micelle structure at the surface, becoming progressively darker. This was very noticable when the puff was touched with a spoon, exposing the much Table XII Glass Cologne and Perfume Aerosol Formulations Ingredients Perfume Oil Ethanol (Anhydrous) Ethanol (95v%) Ethanol (90v%) P-114 P-12 Propane A108 n-Butane A17 U.S.A.: Europe: 1952-1960 — 3** 37 — — 60 — — — 1091-1977 1961-1981 3** — 57 — 36 4 — — 1978-1981 Future* 3*' — — 77 — — 5 15 *DimethyI ether may also be used. **This ingredient varies widely, and may go up to 12% or more in the case of perfume sprays.
Aerosol Propellents 329 lighter interior area. The stabilizing effect of the P-l 15 corrected the problem. It also allowed more product to be filled into a given can size, while still preventing any serious runniness or dense foam problems at the end of the can. P-l 13 is not a true propellent, but rather a nonflammable, volatile solvent. It has been used as a specialty cleaner for electronic and television equipment, as a super-pure solvent for medical adhesives and as a component of colloidal Teflon dispersion-based aerosol dry lubricant sprays. Its density of nearly 1.6g/ml has helped keep the Teflon in suspension. The pressures of P-l 13, P-l 14 and P-l 15 at various temperatures are shown in Figure 7. During the 1960s E.I. du Pont de Nemours & Co. developed Freon Food Propellent C-318 (perfluoro- cyclobutane, C+Fa) specifically for use in food aerosol products. That was a time when there was a gread deal of optimism about the possibility of expanding aerosols into the food specialties area, which unfortunately did not occur. Like P-l 15, P-C-318 helped produce more 100 90 80 70 P-115 W OS D to to W OS a. Po : I lu jrc ca :bc ns P- P- P- L14 LI' LI! P-114 P-113 40 50 60 70 80 90 100 110 120 130 140 TEMPERATURE (°F.) Figure 7. Vapor Pressure vs Temperature for Fluorocar- bons P-113, P-114 and P-115 Table XIII Physical Properties of Fluorinated Hydrocarbon Propellents (Uncommon Types) Formula Molecular Weight Boiling Point (°F) Freezing Point (°F) Pressure (psi-g. at 70°F) Pressure (psi-g. at 130°F) Density (gm./ml. at 70°F) Density (gm./ml. at 130°F) Vapor Density at B.P. (gm./l.) Water Solubility (ml./lOO gm.)* Kauri-Butanol Number Solubility Parameter Hydrolysis in Water (gm./yr.)** Hydrolysis in 1% Na2C03 (g/yr)** Hydrolysis in Water with Steel Strips Present (gm./yr.)** Flammability Limits in Air v% P-13 CCIF3 104.4 -114.6 -294. 456. — 7.01 2.20 0.005 none P-23 CHF3 70.0 -115.7 -247.7 603. — 35.1 0.005 none P-l 16 C2F6 137.9 -108.8 430. — 1.5 0.005 0.010 0.05 none P-132a CHCI2CHF2 146.9 -136.1 -149.1 - 11.4 -1.8 1.492 4.66 751. none P-133 CH2C1CF3 118.5 41.8 -158. 11.3 56.1 1.344 91. 0.010 0.06 none P-227a C3HF7 170.1 -15.5 -258. 65.3 178. 1.0 0.005 P-218 C3F8 188.1 -38.0 297. 1.29 0.5 0.001 0.005 0.04 none none P-3110 C4F10 238.1 28.4 -121. 1.30 0.5 0.001 0.002 0.005 none C-318 C4F8 200.0 21.5 -42.5 25.4 92.0 1.515 9.30 0.5 5.1 5.64 0.0003 0.002 0.040 none *At one atmosphere and 77°F. **Values expressed as grams HCl/liter of propellent/year, at 68°F when solutions of approximately 25% Propellent, 25% Water and ! > Isopropanol are stored in ampules.
330 The Aerosol Handbook stable foam structures and inhibited runniness and other problems when cans were nearly empty. One of the major incentives was to allow the marketing of whipped cream topping cans that were 70v% to 80v% full of product, instead of the 50v% standard that was developed out of concern for the runniness problem. However, when these new, more completely filled dispensers appeared on the market they were shunned by the consumer because of the higher price being charged for cans that seemed to be the same size as before. Eventually, sales of both food-grade propellents dwindled and have been almost discontinued. This is a sad commentary, considering the many millions of dollars spent in attaining their food-approved status. The properties of FP-C318 (as it is often identified) are given in Table XIII (Page 329), along with those of eight other CFCs and FCs that are too uncommon in aerosols to mention here. The Alternate CFC and FC Propellents In the U.S.A. the virtual unavailability of the saturated (fully halogenated) CFC propellents, due to the regulatory ban of 1978, has led to a concerted search for other propellents. The hydrocarbons have major flammability and minor solvency problems, and the compressed gases, such as CO2 and N2O, have excess pressure, which limits their use to coarse spray products containing 6% or less of propellent. These deficiencies spurred research on propellents that seemed to offer either no or moderate flammability, better solvency, reasonable pressures, low toxicity and (of course) relativly low prices. One early combination seemed to be mixtures of P-21 and P-22, covering a pressure range of 8 to 123 psig at 70°F (55 to 845 kPa at 21.1°C), but toxicity studies initiated about 1976 quickly showed problems. The P-21 was considered toxic. Inhalation of 0.1% in air (6 hr daily, 5 days/week x 13 weeks) caused liver damage and excess mortality in the rat, although not in dogs. In addition, inhalation of 1 % in air by pregnant rats (6 hr daily x 10 exposures—days 6-15 of 21-day gestation) was embryotoxic in 15 of 25 rats. The P-22 was considered possibly very slightly mutagenic and teratogenic. The Bruce Ames test for mutagenicity in Salmonella typhimurium bacteria was positive, and a standard teratogenicity test involving inhalation of various concentrations (100 to 50,000 ppm) by pregnant rats (6 hr daily x 10 exposures) showed an 0.45% incidence of microophthalmia (smaller than normal eyes) or anophthalmia (no eyes) in the fetuses. The statistical significance of this finding, particularly below the highest level of 50,000 ppm or 5%, remains questionable. Comparably exposed rabbits were not affected. During 1979, results from du Pont's Haskell Laboratory and from a large scale European teratology study have suggested that no teratogenic hazard for women exists at the OSHA workplace standard of 1000 ppm (v/v). A chronic two-year inhalation study has been conducted on mammals in England. As of January 1, 1982 only the summary results have been made available. They are very encouraging, showing that P-22 is not a teratogen or mutagen at any reasonable exposure level. In fact, there are no effects until long-term exposures at 10,000 ppm or higher are involved. Tumors of the salivary gland were found at 50,000 ppm, long-term, but not at 10,000 ppm. Once the results of the two-year (lifetime) study can be assessed fully it is highly likely that P-22 will be approved and offered for sale as an aerosol propellent in the U.S.A. and Europe. Aside from being non-flammable it has other interesting properties. For example, below 34% P-22, its mixtures with ethanol have lower pressures than corresponding P-12/ethanol blends. A blend of 30% P-22 and 70% ethanol has been suggested for glass aerosols; the pressure is 24 psig at 70°F (164kPaat21.1°C). As of early 1982 the only alternate fluorocarbon propellent in commercial use for aerosol applications was P-152a (CH3CHF2). The physical properties are described in Table VIII. It is chemically very stable, and since it contains no chlorine or bromine it is not involved in the CFC/ozone controversy and is free from any regulatory restrictions. It is a rather ideal propellent, except that it is flammable and some seven times as costly as the competing hydrocarbons. The molecular configuration makes P-152a dipolar and a Table XIV Borderline Solubility Compositions of P-152a, Ethanol and Water Ingredients Ethanol (100%) Water P-152a A 30 10 60 Composi B 45 20 35 tions C 47.7 27.3 25.0 D 45 40 15 The addition of a tiny amount of either water or P-152a to any of these formulas will cause phase separation. In every case the air-free pressure is 62 psig at 70°F (427kPaat 21.1°C).
Aerosol Propellents 331 P-152* WATER Figure 8. Pressure and Phase Diagram for Blends of Ethanol, Water and P-152a Pressure isobars are on an air free basis. Temperature is 70°F (21.1°C) good solvent for both apolar and other dipolar liquids. It is soluble in water to the extent of 0.28% at atmospheric pressure and 77°F (25°C), and to a level of several times that (1.66%) under its own vapor pressure at die same temperature. It is soluble in all proportions in a solution of 47.7% ethanol in water, at 77°F(25°C). Several borderline solubility compositions for the Ethanol/water/P-152a system are shown in Table XIV and the overall picture in Figure 8. Although P-152a is technically flammable, the pure propellent spray cannot be ignited in the flame projection test, and the lower explosion limit (LEL) is 3.9v% minimum in air, compared with 1.6v% minimum in air for isobutane. Actually, P-152a/air mixtures are about a hundred times more difficult to ignite than hydrocarbon/air blends, but this fact has practical importance only when spark sources are used for mixtures that are fairly close to the LEL or UEL compositions. Approximately 32% of either P-12 or P-114 would have to be added to P-152a to make the overall composition non-flammable. Perhaps the single largest product application of P-152a in the U.S.A. is the indoor fogger, due principally to the development of such formulations by a single filling firm. This product is designed to be placed in the center of a room or area to be cleared of both crawling and flying insects, actuated using a latch- down valve design, and sprayed until the can is empty. After three or four hours, during which the toxicants will presumably have penetrated into just about every nook and cranny and have killed the insect population, the area is reentered and aired out. This type of product poses a set of new constraints on the flammability of the aerosol. Instead of spraying just a few grams, as in die case of most insecticides and other aerosol products, the indoor fogger sprays from about 150 to 200 grams into a closed area at one fell swoop. This new and different dispensing mode caused marketers to worry about flammability from a total use standpoint. If the can were to be actuated near a floor furnace, or in a confined area containing a stove or hot water pilot light, could the spray cause an explosion and fire? To minimize that possibility, formulations were developed according to two schools of diought: Ingredients Petroleum Distillate and Toxicants 1,1,1 -Trichloroethane Mediylene Chloride P-152a Propane A108 P-152a Type 8% 48% 20% 24% — Propane Type 8% 60% 20% — 12% The propane type is much less expensive, but is it more flammable? Considering the 1,1,1-trichloroethane as neutral in terms of relative flammability, one must decide if 24% of a somewhat flammable propellent is more or less hazardous than 12% of a very flammable one. Closed drum tests indicate the two formulas are extremely comparable, but there may be other criteria, such as vapor density and diffusion rate, that must be considered for a total answer. The same exercise has been applied to a choice between P-152a and hydrocarbon propellents in the case of plain glass aerosols, which could discharge die entire content upon breakage. The hydrocarbons seem to be preferred strongly in this case, perhaps because the package size is so small (normally 20 g or less), and there would be someone diere to cope with a small fire if it should get started. The final use of P-152a is where its solvent properties are required. In one instance, a medical concentrate high in non-ionic surfactant content could not dissolve
332 The Aerosol Handbook enough isobutane to produce a satisfactory spray. Taking 50 g of concentrate, phase separation took place when over 21 g of isobutane was added. The final formulation consisted of 50 g of concentrate, 25 g of isobutane and 25 g of P-152a. It produced the desired spray pattern. In this case, the P-152a acted as a co- solvent, propellent and pressure booster. Pressure enhancement occurred as a result of its azeotropic properties. In the second case, a surfactant solution designed to provide a fairly unstable sprayed foam was pressurized with a combination of 1 g of isobutane and 4 g of nitrous oxide. The hydrocarbon enhanced foam stability, while the nitrous oxide increased the breaking rate. The combination gave the degree of instability that was desired. As it turned out, these propellents were sufficiently hard to add accurately to the dispenser, that production rates were very poor. In addition, the last portions of the product were delivered with poor foamability, due to the depletion of propellent in the concentrate as the head space increased in volume. All these problems were solved when about 2.5% P-152a and 0.5% hydrocarbon A63 (isobutane/propane) were premixed and added as the 3.0% total propellent. However, the cost did increase to some extent. As a final example, P-152a (along with a small percentage of ethanol) has been used in the formulation of quick-breaking foam products. In the case of the 100 80 e to #60 ft H M 50 40 30 20 10 BO. BUTANE A31 P-133a (CHoCl'CFal — 0 10 20 30 40 50 60 70 80 90 100 PER CENT P-152a Figure 9. Pressure for Blends of P-152a/lsobutane and P-152a/P-133a. Temperature: 70°F saturated CFCs and hydrocarbon propellents, much higher levels of ethanol would be needed; perhaps more than would be wanted to develop the optimum formulation. Rather interestingly, preliminary studies have shown that dimethylether (DME) can probably replace P-152a in each of these examples, although its much greater solubility would necessitate using less of it in the case of quicker breaking and less stable foam structures. It is currently priced at about a third that of P-l 52a, and this merely adds another incentive. P-l52a exhibits a fairly rare property for an aerosol propellent: it forms azeotropic blends with essentially non-polar propellents. Thus, its mixture with 21 % propane exhibits a pressure of 122 psig at 70°F (841 kPa at 21.1°C) and the mixture with 29% isobutane has a pressure of 71 psig at 70°F (490 kPa at 21.1°C). These are the azeotropic maxima, substantially higher than the pressure of any of the pure propellents. On the other hand, with a polar substance such as P-l33a (CH2CI.CF3) a perfectly normal pressure-composition curve is formed. The isobutane and P-133a curves with P-l52a are illustrated in Figure 9. The last commercially significant propellent in this category is P-142b. Like 152a, this fluid was offered to the aerosol industry over thirty years ago. P-152a was known as P-l00 and P-l42b was identified as P-l01 in those early days. Neither enjoyed any significant aerosol applications, perhaps because of their flam- mability and somewhat higher cost. P-142b (CH3.CC1F2) is a CFC and thus must be considered in terms of the ozone question. No regulatory sanctions have been imposed yet, but they are anticipated from a reading of the EPA's ANPR of October 7, 1980, discussed earlier in this chapter. The calculated tropospheric lifetime is 24 years (compared with P-ll at about 91 years) and the ozone depletion relative to P-ll is about 0.09. As a result, approximately 20 pounds of P-l42b would have the same predicted effect upon ozone as one pound of P-l 1. (The figure for P-22 is 34 pounds.) Several observers feel that the regulatory situation being considered by the EPA against all uses of CFCs, including the permit-pound concept, probably will not materialize due to business and political opposition. Firms considering the use of P-l42b should regard the CFC status as only a mild deterrent. P-l42b appears to have a satisfactory toxicological profile, despite an early Ames test result that classified
Aerosol Propellents 333 it tentatively as a very weak mutagen. It appears not to be a teratogen. For instance, pregnant rats inhaling up to 50,000 ppm P-142b in air, 6 hr daily for 10 days during mid-term exhibited no abnormalities in either mother or fetuses. A dominant lethal mutation study, where male rats were exposed to P-142b and then mated, showed no problems in the case of the offspring. The key test is a chronic mutagenic/carcinogenic study underway at Biodynamics Laboratories (Millstone, NJ) with completion set for late 1982. Mammals are exposed to 1,000, 10,000 and 20,000 ppm of P-142b in air for six hours per day. Interim results at six months and twelve months have not shown any ill-effects. The toxicology picture thus far has encouraged at least one supplier to offer P-142b commercially in the U.S.A., another manufacturer has decided to await further data development before making it available for aerosol uses. P-142b is made by reacting HF with 1,1,1-trichloroethane in the presence of selected catalysts and conditions. Despite the similarity between P-142b and P-152a, the latter is made by quite a different route, involving the addition to HF to acetylene. P-142b has a higher density and lower pressure than P-152a. Their properties are compared in Figure 10 and Figure 11. P-142b is probably the most dipolar of the ethane- based propellents, except for P-143a (CH3CF3). Yet it is only about a third as soluble in water as P-152a and has a slightly lower solubility parameter. The departure from expected behavior is due probably to the larger size of the molecule. P-142b is only slightly flammable, having flam- mability limits in air of 6.0 to 15.0v%. By the same test, a blend of 74% P-142b and 26% P-12 is non-flammable, although borderline, 66% P-12 is required to produce the same effect with P-152a. Both P-142b and P-152a are incapable of producing a flame extension when sprayed. They evaporate completely from flash point testers without giving any flash point or fire point. At this time, due to the uncertain toxicological and regulatory situations, plus the fairly high price, P-142b is not used to any measurable extent in aerosols. In the past it has found a few applications in glass aerosols because it is a better solvent for perfume ingredients than P-l 14 (or the butanes), and has also been used in one or two quick-breaking foam products. One report suggests that the addition of a P-142b/propane propellent to shaving creams will result in richer foams, with a more pearl-like or satiny surface and texture. The defatting effect of P-l42b would have to be evaluated carefully for such applications. 1.25 1.20 1.15 1.10 0.90 -^H4^ I I—1 P| 1 ^*V^ : 1 1 * P-152a 40 50 60 70 80 90 100 TEMPERATURE (°F.) 110 120 130 140 180 140 £ 100 P-142b £ S en W tt 60 a. 1— ,P-152a ■142b 40 50 60 70 80 90 100 110 120 130 140 TEMPERATURE (°F.) Figure 10. Density of P-l42b and P-l52a at Various Figure 11. Pressure of P-l42b and P-l52a at Various Temperatures Temperatures
334 The Aerosol Handbook The Bromochlorofluorocarbons and Bromofluorocarbons These aeroform fluids can function as aerosol propellents but are not normally used as such, so their discussion is brief. There are about six or seven commercially available compounds, all under the tradename of Halon, but only Halon 1301 (CF3Br) by duPont and Halon 1211 (CF2ClBr) by I.C.I. United States Inc. are of any real importance. They are used almost exclusively as fire extinguishing agents, breaking the combustion reaction chain and cooling the fire. Two major reaction chains are involved: free-radical and ionic. The major decomposition products are CO2, HBr, HC1 (if CI is present) and HF, but minor amounts of Br2 (bromine), COBr2 (carbonyl dibro- mide), COCh (phosgene — if CI is present), COF2 (carbonyl difluoride) and carbonyl mixed halides are formed. Although the Halons have not been implicated directly in the regulations relating to the CFC/ozone 0 ■—*—i—J—1—1—1—'—'—'—'—'—'—'—'—'—' ' '——* 40 50 60 70 80 90 100 110 120 130 140 TEMPERATURE (°F) controversy, the omission probably arises from their disassociation with aerosols in general. They are manufactured in more limited quantities than the major CFCs. Certain Halons are very susceptible to tropospheric reactions. For example, Halon 1211 in the presence of 400 ppm of moisture will hydrolyse and produce sufficient acid to perforate a tinplate aerosol can within 24 hours. It would not be expected to survive hydrolysis in the troposphere to any extent, and may therefore be considered as non-threatening to stratospheric ozone. The Halons have a wide pressure range, and blends have been used often. Combinations with P-12 and also CO2 have been employed, mainly to increase die pressure of Halon 1211. The pressures and densities of selected Halons and blends are shown in Figure 12 and Figure 13. The 20% P-12 and 80% Halon 1211 mixture is now used widely for smaller fire extinguishers outside the U.S.A. They may be found in cars, boats, garages, workshops, laboratories and in some houses. Some con- l i i 1 1 ' 0.9 —!—!—|.—j—1— A = Halon 1211 __! I_J l_ l_ B = Halon 1301/1211 (30:70) j J ! I ' | C = 209c P-12 + 80% Halon 1211 0.8 ——|—i—!—p- D = jjajon 130i I I i ' . , , , , . 40 50 60 70 80 90 100 110 120 130 140 TEMPERATURE (°F) Figure 12. Pressure of Common Halons and Blends Figure 13. Density of Common Halons and Blends
Aerosol Propellents 335 tingency studies are being performed using a 16% P-22 and 84% Halon 1211 composition, in case sanctions against P-12 are increased. On a practical basis, to sell a fire extinguisher in the U.S.A. one must obtain Underwriters Laboratories (UL) approval. This is an extremely complex, long and costly affair; so much so that no ordinary aerosol dispenser has yet been approved. One of the numerous test requirements involves the extinguishment of an n-heptane fire having a fuel surface of 1.0 sq. ft. (305 x 305 mm) at -40°F (-40°C). The relatively large, heavy- duty fire extinguishers, typically holding from 4 to 7 lbs. (1.8 to 3.2 kg), are formulated by adding sufficient CO2 to Halon 1211 to generate a 70 psig minimum pressure at 70°F (483 kPa at 21.1°C) in order for the product to put out fires with an operating range of -40° to 120°F (-40°C to 49°C) minimum. Such products have a Class B fire rating and Class C electrical rating. They must have a small (patented) pressure gauge integral with the dispenser to assure that no CO2 leakage has occured, dius preventing proper operation at very low temperatures. The British Standards Institute, which is the equivalent of the UL in the United Kingdom, is not as strict, and for this reason aerosol fire extinguishers of the non-returnable type represent a significant portion of the aerosol busines in that area. Similar situations apply over much of the rest of the world. The toxicology of the Halons has been rather well defined. Once these substances are used to put out a fire, the noxious nature of the reaction products (typically at the 10 to 50 ppm level) will be sufficient to limit human exposure to both the unreacted Halon and its decomposition residues. One of the less common Halons is unique in that it has one of the most intense cardiac sensitization and arrhythmia profiles ever recorded. This is not a significant problem with the common Halon materials. The Hydrocarbon Propellents The hydrocarbon propellents became the dominant type worldwide during 1979. During that year and through at least 1982 these gases will have accounted for about 90% of all U.S.A. aerosol units, and for a requirement of about 300 million pounds per year (136 million kg/yr). In Canada about 82 % of all aerosols contain hydrocarbon propellents, although sometimes in combination with CFC types. The figure is the result of a selective ban, directed at hair sprays, colognes and underarm products, since these accounted for the great bulk of CFC sales in that country. Rather interestingly, the ban results only to "true propellent" uses; not to solvent or carrier uses. This tends to exempt P-11 and P-113 from consideration. As one result of this situation, the leading antiperspirant spray now uses a formulation consisting of about 10% concentrate, 65% P-11 and 25% hydrocarbons. It is considered superior to the straight hydrocarbon types since it does not inject so much acidic dust into the air during use. The liquid droplets of P-11 carry over 88% of the astringent aluminum chlorhydrate to the underarm area and then quickly evaporate. In contrast, the isobutane in straight hydrocarbon propellent types evaporates almost immediately upon release, leaving nothing but a bit of oily material (isopropyl myristate and/or volatile silicone) to carry the aluminum compound to the skin. As a result, only about 55% is actually transferred; the rest floats about as a dusty, irritating cloud in the air, to the aggravation of the user. This situation is further elucidated in Figure 14. In Europe the use of CFCs also decreased substantially during the post Rowland-Molina period, and particularly during 1978-1982. After a review of the UNDERARM; ICFC FORMULATION 4% Aluminum Chlorhydrate FORMULA TYPE HAP FORMULATION 14% Aluminum Chlorhydrate TRANSFER EFFICIENCY ("o) 1I/P-I2 (CFC) (Old U.S., present Japan, etc.) 88-91 P-11/25%Isobutane (CFC/HAP) (Canada, Australia, etc.) 83 - 86 ■Isobutane (HAP) (Present U.S., some Canada, etc.) 48-59 Propane/Iso.pentane (HAP) 78 - 81 Propane/n. Butane/1,1,1-Trichloroethane 72 Fatty Acid/Silicone Gum (U.K. #1,589,229 & 1,589,230) 75 - 82 Iso.butane/Water (Sea-Chem, experimental) 75 - 80 Optimum Package/Formula (U.K. #1,591,312 & 1,591,365) No data. CFC = Chlorofluorocarbon propellent HAP = Hydrocarbon aerosol propellent Figure 14. Anti-Perspirant Transfer Efficiency
336 The Aerosol Handbook CFC/ozone theories the EEC asked for a voluntary reduction of 30% in CFC aerosol uses by January, 1982, compared with the 1976 level, and promised a mandatory reduction if this was not accomplished. The reduction was in fact realized, although much more so in some countries than others, and the EEC has now recommended a continuing voluntary freeze at a level not to exceed 102% of the Jan. 1, 1982 figure. The results of a Metra, Ltd. survey of the 1979 propellent selections for various European countries are incorporated into Table XXV of the Aerosol Marketing chapter. The 1982 usage level varies widely from country to country in Europe. For example, it extends from a level of about 70% of all aerosol units in France, where about 25% of their production is in 100% CFC type fragrance products, to only 2% in Norway and Sweden, where virtual bans on CFCs are in place. The usage level also varies widely from filler to filler, partly depending upon the filling facilities that are available. The data in Table XV illustrate the differences between the four largest filling installations in Switzerland, as well as the breakdown of uses between product categories. From 1982 on, the European consumption of hydrocarbon propellents will increase further, as marketers Table XV Aerosol Propellent Use Profile in Switzerland (1977-1978) Filler 1. 2. 3. 4. Product Mix All kinds of aerosol products Principally cosmetic items All kinds of aerosol products Only cosmetics Propellent Usage CFCs HAPs 73% 82% 82% 100% 27% 12% 18% 0% Per Cent of Use (By Weight) Product Group CFC Only CFC/HAP HAP Only Cosmetics Hair Sprays Underarm Products Perfumes/Colognes Others House and Garden Chemical/Technical Paints and Lacquers Pharmaceuticals and Veterinarian Items Overall 64.7 90.4 100.0 12.6 7.9 85.2 10.5 88.5 47.2 35.3 3.2 0.0 10.1 36.4 0.0 0.0 7.6 16.0 0.0 6.4 0.0 79.3 55.7 14.8 89.5 3.9 36.8 Courtesy of Dr. Willi Roth - ASA become more confident of the new formulas, and as fillers develop more sophisticated gassing facilities to handle these more economical gases. In the U.S.A., isobutane is by far the most popular hydrocarbon propellent, accounting for about 70 to 75% of the total aerosol use of hydrocarbons. This is despite the fact that this gas accounts for only 4% of the composition of well-head LP-gas mixtures and is the most expensive of the common hydrocarbons. Propane occupies about a 15 to 20% market share, while n-butane has around a 10 to 15% share. In other countries the use of hydrocarbon often depends upon what is available locally. For example, the natural gas fields in southern Australia yield a combination of approximately 60% propane and 40% butane that is refined and sold as is for most aerosol uses. If a higher or lower pressure propellent is needed, it is produced from the basic blend by distillation and sold at a modest premium. About 20% of all the n-butane that goes into aerosols enters as a co-propellent, as a recognized ingredient in isobutane and (to a much lesser extent) in propane. In a similar fashion, co-propellents include up to about 3 % ethane in propane and 3 % isopentane in blends high in n-butane. The purified, Aerosol Grade propellents are specified to have a minimum purity of 95.0 w%, and this leaves ample room for the co-propellents as mentioned. For some aerosol products, such as paints, lacquers and certain industrial types, the use of purified (low-odor) Aerosol Grade hydrocarbons has been deemed unnecessary by many marketers. The Commercial Grade LP-gases are used instead. On the average, these compositions have a higher odor level and a broader pressure range than the Aerosol Grade gases, but they are also significantly less costly. As a general rule the Commercial Grade materials can be considered to have purities above about 90.0 w% for the individual gases, but specifications are tied more closely to pressure range than actual composition. Most of the Commercial Grade aerosol propellents are either propane or blends containing a substantial amount of propane. In early 1982 propane was selling at $0.39 per gallon ($0.10 per liter) and ethane at only $0.21 per gallon ($0,055 per liter). This price difference indicates the incentive for refineries to inject as much ethane into their Commercial Grade propane as possible, within the pressure limit of 224 psig at 100°F (1.54 MPa at 37.8°C) laid down by the American Petroleum Institute (API) and other groups. Whereas the pressure of Aero-
Aerosol Propellents 337 sol Grade propane is 114 psig at 70°F (786 kPa at 21.1°C) as a maximum, the pressure of the Commercial Grade material may get to 128 psig at 70°F (883 kPa at 21.1°C), as a result of an ethane content approaching 4.0%. Steps are underway to allow the introduction of even higher amounts of ethane. The presence of ethane is not a problem, except that it may act to elevate the pressure of the finished aerosol product. Ethane will provide a finer break-up of the spray than propane, but this is rarely a disadvantage within the limits involved in this case. The LP-gases have natural origins, being extracted from both crude oil and natural gas supplies. U.S.A. natural gas contains an average of 25.9% ethane (1981 figure; dropping about 0.8% per year), 12% propane, 7% n-butane and 3.7% isobutane. The largest component of natural gas is methane, generally at over 50%. Smaller constituents include n-pentane, isopentane and the isomeric hexanes. Carbon dioxide is usually present. Finally, there are a large number of other compounds in die raw gas streams which are considered undesirable for aerosol applications, due to odor, reactivity or other factors. They include the unsaturated hydrocarbons, such as ethylene CH2:CH2, propylene CH3 • CH: CH2, 1-butene CH2: CH . CH2 . CH3, 2-butene CH3 • CH: CH • CH3, isobutylene (CH3)2C:CH2, the pentenes, acetylene CH:CH, methyl acetylene CH3.C:CH, allene CH2:C:CH2 and butadiene CH2:CHCH:CH2, as well as sulfur compounds; e.g. hydrogen sulfide H2S, akylthiols (formerly mercaptans) CH3SH, etc. and dialkyldisulfides RSSR'. Moisture may also be present. In any given well these individual components may vary quite widely. Some wells have had to be capped because the gas stream contained over 50% hydrogen sulfide and mere was no practical way of using the product. Others are unusually rich in acetylene, which is an impurity difficult to remove. These particular wells are shunned by the firms who purify LP-gas into aerosol propellents. Finally, the ratio of n-butane to isobutane varies from about 80:20 to about 60:40, depending on the well. Wells with the higher stream contents of isobutane are preferred for aerosol purposes. Despite the fact that only 0.1 percent of the U.S.A. propanes and butanes are directed to aerosol propellent applications, this segment amounts to sales of about $70 million per year. About 58,000,000 gallons of raw feedstock are purified to Aerosol Grade materials, and an * * AEROPRES CORPORATION PHILLIPS CHEMICAL CO. | U.S. CONSOLIDATED GAS CO. CITY SERVICE COMPANY TECHNICAL PETROLEUM CO. DEMERT AND DOUGHERTY INC. INDUSTRIAL HYDROCARBONS DIVERSIFn-D C&P CO. .* [ SKELLY OIL CO. (ETC.) "UTURE - ' >- $ 1 § K W i i IVE PAINT & COATINGS Figure 15. Refiners and Resellers of Aerosol Hydrocarbon Propellents Two of the largest resellers of Aerosol Grade hydrocarbons in the U.S.A. and Canada are Diversified Chemicals and Industrial Hydrocarbons. additional 11,000,000 gallons or so are sold directly to aerosol fillers as the Commercial Grade product. Six firms are currendy engaged in the purification of one or more of the gases in the group consisting of propane, n-butane and isobutane. They are listed in Figure 15. The Aeropres Division of Aeropres Corp., the Phillips Chemical Co. subsidiary of the Phillips Petroleum Co., the City Service Co. and the Technical Petroleum Co. are basic suppliers of Aerosol Grade hydrocarbons. They can provide tiiis grade of propane, n-butane and isobutane, or virtually any mixture of these gas liquids. On the other Hand, U.S.G.L., Inc. of the U.S. Consolidated Gas Co> can supply only isobutane. DeMert & Dougherty, Inc. is a Chicago area aerosol filler who installed a purification unit during 1980 and is willing to sell excess propane and n-butane. There are several resellers of Aerosol Grade hydrocarbons in the U.S.A. and Canada. Two of the largest are Diversified Chemicals and Propellents Co. (Chicago area) and Industrial Hydrocarbons, Inc. (Los Angeles area). Diversified Chemicals and Propellents Co. provides their Aeron® gas liquids via seven distribution terminals across the U.S.A. and also does business in Canada. They are now installing their own propellent purification facilities. On the other hand, Industrial Hydrocarbons, Inc., sells Phillips 66's A-17® (n-butane), A-31® (isobutane), A-108® (propane) and blends primarily in the Western States. Both firms sell purified hydrocarbons for other purposes, and have business interests that include CFC applications, resale of methylene chloride, and so forth.
338 The Aerosol Handbook 1.40 1.30 1.20 . 1.10 1.00 0.90 0.80 0.70 0.60 OrSO 0.40 0.30 0.20 0.10 ISO. EUTANE AND N.BUTANE LIST "JFMAMJJASONb^FMAMJjASbNDJfMAMJJASOND -^ 19 7 9 T-r< -19 8 0- :*-.- - 19 8 1- *- Y E A R a Figure 16. Field Grade and Aerosol Grade Prices of the Common Aerosol Hydrocarbon Propellents Spot prices for Field Grade hydrocarbons are updated weekly. Prices for Conway, KS hydrocarbons are illustrated. Prices for Mt. Belvieu and Sarnia (Canada) gases are generally within ± 10% of the Conway KS figures. They are for tankcars, f.o.b. source. List prices for Aerosol Grade materials are for tankcars, f.o.b. source. For those aerosol paint fillers and others who may wish to purchase a Commercial Grade hydrocarbon propellent, there are sellers such as Phillips Petroleum Co. (out of the U.S. Industrial Chemical Co.'s plant in Tuscola, IL, for example), and Dome Petroleum Ltd. (Sarnia, Ontario, Canada) Terminals also exist at Conway, KA, Mont Belvieu, TX and other locations. This grade of propellent is also known as feedstock quality, fuel grade, and field grade. The prices are revised on a weekly basis. They are compared with the Aerosol Grade prices for propane, n-butane and isobutane in Figure 16. The price of propane, n-butane and isobutane is affected by massive factors outside the realm of the aerosol industry. Natural gas is the major source for these gas liquids, and the extent to which it is needed for a myriad of other uses controls the cost. After the natural gas undergoes CCvstripping, deethanization and other operations, the gas-processing plant uses a depropanizer unit to separate the propane, after which the isomeric butanes are separated in their turn. The remaining feed stock is distilled into relatively pure n-pentane, isopentane, hexanes and other light fractions according to need, but these are of limited interest to the aerosol formulator. The mixed butanes may or may not be separated. They are very often used directly as components of liquefied petroleum gas (LPG) and synthetic natural gas (SNG). Starting in 1980 the mixed butanes (especially about 60% n-butane and 40% isobutane) began to be used along with propane in the formulation of certain purified, lower cost aerosol propellents. The blends had pressures in the range of about 24 to 70 psig at 70°F (165 to 483 kPa at 21.1°C) and were sold under such tradenames as Aeropin® (Aeropres) and Aerosol BIP® (Phillips). Their lower cost could be justified on the basis that the approximate $0.10 to $0.14 per gallon cost (depending on freight increment) of separating the butanes was saved; also, n-butane was less costly than isobutane, and this dictated a savings when compared with the usual isobutane/propane combinations. The domestic market for propane, n-butane and isobutane divides into three categories: fuel use, chemical use and net refinery use. The Aerosol Grade propellents were effectively taken out of the fuel classification through an action of the U.S. District Court for the Western District of Louisiana (June 15, 1981) which disallowed any Department of Energy regulation of these gas liquids as fuels. Thus they were, in effect, placed in the "chemical uses" category. Regardless of how they are classified, the aerosol gases compete with fuel and other applications that require propane, n-butane and isobutane. These gas liquids in 1981 accounted for 67.3 % of all ethylene production, leading to polyethylenes. About 3.6 billion pounds per year (1.6 million metric tons per year) of n-butane finds its way into chemicals: ethylene, acetic acid, maleic anhydride and butadiene, for example. Almost 1.0 billion pounds per year (0.44 million metric tons per year) of isobutane is used, mainly for tertiary butyl alcohol, but also for making propylene oxide via the Oxirane process, now owned by Arco. Propane will be the cheapest feedstock for steam crackers over the next decade. The Oxirane process is of special interest to aerosol people. It involves a two-stage reaction mechanism, with isobutane, oxygen and propylene reacting to produce tertiary butyl hydroperoxide (CHj)3C.O.OH as an intermediate, which then produces propylene oxide and also tertiary butyl alcohol as a co-product. The peroxide is characterized by having a strong, chlorinelike odor even at very low levels. It has been a sporadic site-generated contaminant in bulk tanks that hold isobutane or blends containing isobutane. It is particularly
Aerosol Propellents 339 likely to be produced in those tanks that may have previously contained P-ll. The catalytic effect of iron/iron oxide and some moisture seems to allow the reaction to build up to at least 80 ppm. of the peroxide during ordinary outdoor storage conditions. To prevent a recurrance of the problem, many fillers empty, degas, and then sand-blast the affected bulk tank. By far the major uses of the butanes are in the fuel area, in both heating gas and in gasolines. n-Butane is added directly to gasoline stocks to increase volatility for winter driving conditions. Isobutane is also added, to some extent, directly from the isomeric blend with n-butane, but mostly after alkylation. The butane alkylate has a high octane number and is much in demand. Anticipating periodic shortages of isobutane (and thus a higher price) Phillips, Tenneco and Marathon have all installed isomerization units to convert n-butane to isobutane. The large unit at Phillips' Borger, Texas refinery is used to convert mixtures of isobutane and n-butane to essentially 100% isobutane for aerosol purposes, among other applications. Unsaturated C4 compounds (mainly isobutylene) are always present in the butanes feedstock, and by adding slightly over the stoichiometric amount of hydrogen, all these high odor impurities are converted to their saturated counterparts during the basic isomerization process. A typical reaction involving 1-butene would be as follows: Cri2:Cri.Cri2'CH3 + H2 -* Cri3.Cri2'Cri2-dri3 (1-butene) Cri3.Cri2-Cri2-Cri3 —* (Gri3)2CrI.Gri3 (n-butane) (isobutane) Phillips isobutane, made by this process, is unique in that it has much less than 1 ppm. of remaining unsaturates, whereas the industry standard for Aerosol Table XVI Pressure Specifications for Aerosol Grade Hydrocarbon Propellents Temperature = 70°F(21°C) Hydrocarbon Propane A-1-8 Isobutane A-31 n-Butane A-17 Aeropres 110 ± 4 31 ± 2 17 ± 2 De Mert & Dougherty 123 (max.) — 17(min.) Diversified 108 ± 3 31 ± 2 17 ± 2 Technical 110 ± 4 31 ± 2 17 ± 2 Phillips 108 ±3 psig 31 ± 2 psig 17 ± 2 psig Note: At an industry meeting in 1979 with representatives from five suppliers or resellers present, typical properties of Aerosol Grade hydrocarbons were agreed upon as: propane 108 ± 6, isobutane 31 ±2 and n-butane 17 ±2 psig at 70°F. These were later printed in an industry publication. Grade gases is 10 ppm. maximum. Butane samples from other countries have been examined with the finding that they sometimes contain as much as 475 ppm. of these odorous and relatively reactive impurities. Purification of Field Grade Propane, n-Butane and Isobutane Field grade hydrocarbons suitable for rectification into Aerosol Grade propellents generally contain at least 95% w% of the primary hydrocarbon ingredient and have 70°F (21.1°C) pressures in the stipulated range for the final product, as shown in Table XVI. Maintaining the pressure specification is particularly difficult in the case of propane. The absolutely pure compound has a pressure of 109.3 psig at 70°F (754 kPa at 21.1°C), but each 1% of ethane that is added increases the pressure by 3.9 psi (27 kPa). Introducing butanes to propane does very little to depress the pressure within the narrow limits that can be added. Rejection or blending with lower pressure propane are the only realistic solutions. The purification of field grade stocks consists of the strong reduction or removal of active and odorous unsaturates and sulfur compounds, plus water. The total content of these ingredients is in the range of about 0.005 to 0.200%, with an average of about 0.015%, although the figures vary widely between sources and even within a given source, measured at different times. Two pipeline supply sources are known to vary in acetylene content from below 0.0001% to above 0.2200%. This can be a serious affair, because this impurity is very difficult to remove by passing the feedstock through absorbent solids. A rather typical analysis profile of the in-plant feed, field-grade propane, field grade isobutane and field grade n-butane streams at Dome Petroleum Ltd.'s
340 The Aerosol Handbook "National Gasoline Plant" at Sarnia, Canada is given in Table XVII. Not shown is the condensate stream, composed of about 25% n-pentane, 25% isopentane, 50% hexanes and higher, and about two-thirds of the C4 unsaturate content of the in-plant feedstock. Several methods are available for the removal of unsaturates, sulfur compounds and water. One procedure, used little in the U.S.A. but known in other parts of the world, involves the ambient temperature reaction of these impurities with 99% sulfuric acid. Propylene absorbs to give a series of polymers, plus some propyl hydrogen sulfate that yields isopropanol when hydrol- ized. Isobutane absorbs even more easily, to give 2,4,4-trimethylpentene-l and many other polymers, plus some tertiary butyl hydrogen sulfate that produces tertiary butyl alcohol on the addition of water. This alcohol has a strong camphor type odor and may contaminate the hydrocarbon with this odor unless washed thoroughly with water. Butene-1 and butene-2 are polymerized to some extent and also yield secondary butyl alcohol on the addition of water. Acetylene is not polymerized by sulfuric acid, but yields acetaldehyde CH3CHO and crotonaldehyde CH3CH:CHCHO instead. Hydrogen sulfide, alkythiols and alkydisulfides are oxidized by sulfuric acid, giving sulfur dioxide, monosulfoxides and monosulfones as illustrative of the large variety of possibilities. After the acid treatment the cleaned gas liquids are scrubbed through a Raschig ring column of 10% sodium hydroxide, followed by a column containing clean water. At a typical operating temperature of 60°F (15.6°C) propane dissolves 129 ppm. of water and the butanes dissolve only about 54 ppm. This means that the usual reduction to the specification of 25 ppm. water (maximum) can be accomplished readily with solid drying agents. If the butanes are below 40°F (4.4°C) no desiccation is necessary; only entrapment of water droplets with aluminum turnings or some similar hydrophilic maze-like material. Optionally, the finished gas stream can be further "polished" by passing it through a granular type of activated carbon, such as Darco S-51, then through a very fine filtration unit and into a storage tank. In the U.S.A. the sulfuric acid purification process is used generally only if unsaturate levels are about 0.25 to 1.00%, which is fairly rare, or if sulfur compound levels are excessive. Even then, it is only a preliminary purification step, with the final process involving absorption of contaminants by means of activated carbon and zeolyte (molecular sieve) mixtures. A basic sketch of such a system is shown in Figure 17, for the purification of field grade isobutane. This system can be used for other propellent gas liquids, or expanded to simultaneously run other hydrocarbons by adding storage tanks, piping and purification towers. A suggested procedure involves the fairly rapid (high-stream) passage of the gas liquid through a preliminary tower containing trays of activated carbon granules and Zeolytes 4A and 13X, then a slower passage through a (low-stream) tower filled with the Table XVII Plant Feed and "Field Grade" Hydrocarbon Analyses (Typical month, at Dome Petroleum Ltd. Sarnia, Canada.) Ingredients Methane Ethane Propane Isobutane n-Butane Isopentane n-Pentane Hexanes, etc Unsaturated Hydrocarbons Sulfur Compounds Water Plant Feed 0.05 1.7 50.3 9.8 17.3 5.0 4.6 11.3 0.03 trace trace F.G. Propane 0.1 2.9 94.9 2.0 0.1 0 0 0 0 trace trace Per Cent By Weight F.G. Isobutane 0.01 0.03 2.4 96.2 1.3 0.05 0.03 0 0 trace trace F.G. n-Butane 0.01 0.02 0.4 1.9 96.0 1.9 0.2 0 0 trace trace The in-plant feed is distilled to the "Field Grade" gases, plus condensate, consisting of about 18% of the in-feed and composed of C5, Ce and some C7 hydrocarbons. For propane and n-butane, unsaturates are generally below 42 ppm. sulfur compounds are almost always below 0.6 ppm, according to one user.
Aerosol Propellents 341 180 FOOT ENCIjOSURE Figure 17. Butane Purification Facility C.H. = Control House(14'x28') P.U. = Purification Unit R.U. = Regeneration Unit F.G.I. = Fuel Grade Isobutane (Waste) Cost: $1,800,000 (1982) Capacity: 3 million gallons per year Available consultants: George A. Brock & Associates, Inc., and Linde Division, Union Carbide Corporation same absorbents. Molecular sieve absorbents are supplied by W.R. Grace & Co. and the Linde Division. Each of the three absorbent materials has a well-defined spectrum of utility, and ratios should be selected in keeping with the type and amounts of impurities to be captured. For example, Zeolyte 4A is particularly useful as an absorbent for water. For larger units (those above 1 or 2 million gallons of pass-through per year) it is generally recommended that absorbent reactivation equipment be installed. Eventually even a large tower will reach impurity saturation widi respect to some specific ingredient. Then, if elution continues, some other impurity may be absorbed preferentially, displacing the saturated first ingredient as a line slug. For example, acetylene is weakly absorbed by the zeolytes, and once saturation occurs, it can be supplanted easily by such large-scale impurities as isobutylene. Pure acetylene has only a very slight odor, and without constant gas chromoto- graphic surveillance, could easily be displaced totally into the Aerosol Grade propellent storage tank. Depending upon the make-up of the field grade gas liquids and the size of the purification tower, anywhere from about 200,000 to 1,000,000 gallons can be passed through before impurities start to percolate into the finished product line and it becomes obvious that regeneration is necessary. Zeolytes in particular are expensive commodities, so that replacement is not feasible. They must be regenerated, either in site or at a remote service location. There are two major types of regeneration equipment, both in the $500,000 range: salt bath heaters and burning bed heaters. Both operate at about 700°F (370°C). The salt bath heater of about 2.5 million BTU seems to be preferred. The tower is pumped free of any gas liquids and the absorbents are then heated for a four hour period, using hydrocarbon gas that has been heated by passage over a hot salt bath. After temperature is reached, the hot gas is pumped off to a cooling unit, carrying with it all the impurities, which may total as much as 2,000 to 4,000 pounds (907 to 1814 kg) depending on elutants and tower size. This takes about four hours and is followed by a final hour period for cool down of the unit. A typical, well-conducted regeneration will only deplete absorptive efficiency by about 1 or 2%, due to powdering and unsaturated gas polymerizations on the zeolytes. However, if periods much longer than four hours are used for the two heat-utilizing stages, bed life can be shortened considerably. At the cooling tower the heavily contaminated gas liquid will form a layer over the condensed water, allowing the water to be decanted and sewered. The remaining 1,000 to 2,000 gallons (3,790 to 7,570 liters) of malodorous liquid gas can be eliminated in various ways, perhaps by being vended to a local fuel dealer as No. 5 Grade heating gas. A typical 12,000 pound (5,440 kg) tower can hold up to about 110 pounds (50 kg) of acetylene, 1,050 pounds (476 kg) of unsaturates such as propylene, isobutylene, butadiene and so forth, and up to 3,000 pounds (1,360 kg) of any combination of water and sulfur compounds. Tower capacities are generally in the 8,000 to 16,000 pound (3,630 to 7,260 kg) range and nearly all installations have regenerative capacity built into the system. At least two large marketer-fillers (captives) of aerosol products have purification towers to "polish" Aerosol Grade gas liquids for use in cosmetic products. Up to about 1979 some suppliers provided Aerosol Grade stocks relatively high in unsaturates, giving the products a rather stale, undesirable odor. As an example, the Aeropres Division used to offer two grades of propellent: Aerosol and Cosmetic grades. They were specified as having maximum unsaturate content of 1,000 ppm. and 100 ppm., respectively. But later on, manufacturing improvements allowed Aeropres to produce all their propellents with a maximum unsaturate content of only 10 ppm. This included me "Aeropres"® propellents (Aerosol Grade propane, n-butane and isobutane, plus propane/isobutane blends) and after June 1, 1980 the new "Aeropin"® blends made from propane and mixed butane feedstocks.
342 The Aerosol Handbook In other parts of the world many aerosol fillers have their own absorption equipment, although some has fallen into disuse as local gas suppliers have improved their quality. In England and France, where hydrocarbon odors are taken very seriously, many fillers still operate ' 'polishing'' columns. In Latin America at least one filler has installed an activated carbon ' 'polishing'' tower to remove occasional high levels of acetylene that contaminate the local Aerosol Grade gas liquids. The tower can be regenerated easily by heating to 150°F (65.6°C) and can also remove sulfur compounds rather effectively, if they are present. As in the case of molecular sieve columns they should be used only for the intended purpose of purifying hydrocarbon propellents. For example, the introduction of CFCs, methylene chloride or other chlorocar- bons into the hydrocarbon stream, such as might arise from bulk tank transfers, will act to blind the sieve components and greatly impede their efficiency. Inspection of Purified Propane, n-Butane and Isobutane The several suppliers of aerosol hydrocarbon gas liquids have developed various specifications over the years, and the differences between them are rather remarkable. Typical product specifications are illustrated, in Table XVIII. When typical 30,000 gallon (114,000 liter) tankcars or 8,300 gallons (31,440 liter) tanktrucks of product arrive at filling plants they are sampled prior to unloading and the sample is then checked for pressure, odor level and composition. No further tests are performed. Smaller fillers, who may lack a recording gas/liquid chromatograph, will not be able to check the composition. To test odor, a favorite method is to pour the liquid propellent down the side of a glass beaker (contained in a well ventilated hood) until about 5 ml have been col- Table XVIII Hydrocarbon Propellent Specifications Aeropres Property Purity-Wt. % (minimum) Purity-Mol.% (minimum) Pressure (psig) 70°F(21.1°C) 100°F (38°C) 130°F (54°C) Initial Boiling Point (°F) Dry Point (°F) Flash Point (°F) Specific Gravity of Liquid (60°F) Moisture (ppm) (maximum) Sulfur (ppm) (maximum) Unsaturates (ppm) (maximum) Residue (g/100 ml) (maximum) Total Saturated Compounds (w%) Acidity of Residue Odor (Panel) Prop. 95 110 ± 4 25 5 10 0.0005 Neut. Pass isoBut. 95 31 ± 2 25 5 10 0.0005 Neut. Pass n-But. 95 17 ± 2 25 5 10 0.0005 Neut. Pass Diversified Prop. 95 108 ± 3 172 ± 3 257 ± 3 -46 -42 -156 0.508 <5 <1 0 >99.9 Pass isoBut. 95 31 ± 2 59 ± 2 97 ± 2 9 15 -117 0.563 <5 <1 0 >99.9 Pass n-But. 95 17 ± 2 37.5 ± 2 67 ± 2 28 33 -101 0.584 <5 <1 0 >99.9 Pass Phillips Prop. 98 108 ± 4 5 0.0005 >99.9 Neut. Pass isoBut. 95 31 ± 2 5 0.0005 >99.9 Neut. Pass n-But. 97 17 ± 2 5 0.0005 >99.9 Neut. Pass
Aerosol Propellents 343 Table XIX Typical Composition of Aerosol Grade Propellents Composition (mol%) Ethane Propane isoButane n-Butane Pentanes Propane 0.5 max. 95.0 min. 5.0 max. 0.5 max. — Isobutane 3.0 max. 95.0 min. 5.0 max. 0.1 max. n-Butane 1.0 max. 3.0 max. 97.0 min. 2.0 max. lected. The beaker is swirled to facilitate evaporation. At the point where the last amount is about to volatilize the contents are sniffed for possible off-odor. In some cases odors are compared with those of standards. More propellent is rejected for off-odor than for any other reason, by far. The gas/liquid chromatographic (GLC) analyses is aimed at determining the composition of the major components, those over 0.05 to 0.10%, rather than scanning for contaminants. A typical GLC trace is shown in Figure 18, for Aerosol Grade isobutane, using an instrument with integrator and recorder. A recent CSMA publication contains a consensus of the hydrocarbon suppliers regarding die typical compositions for the three common propellents. They are shown in Table XIX. To reduce this to a practical basis the figures may be compared with those listed on laboratory test reports covering tankcars of isobutane received from four major suppliers, as shown in Table XX. All four lots were approved as excellent, during 1980. If a GLC assay yields good results, pressure testing may be superfluous, unless the partial pressure of air is in question. Unlike the CFCs, air is absent in hydrocarbon receipts, for all practical purposes. Pressure tests are normally made at 70°F (21.1°C), so diat a direct comparison with the specification pressure range at that temperature can be made. For blends, the 70°F (21.1°C) pressures should be that stipulated in the blend designation + 2 psi (14 kPa). Both suppliers and fillers often prefer to check pressures at temperatures between 60°to 80°F (15.6° to 26.7°C) instead of equilibrating die sample to 70°F (21.1 °C). They then convert the result to 70°F (21.1 °C) standard temperature by means of a chart. For example, an isobutane pressure of 36.00 psig at 75°F would convert to 31.75 psig at 70°F using a factor of 0.85 psig/°F. (In the ISO system, isobutane pressure 3.95 7.38 12.40 1155403 15SS6 1.423 97.24 1.337 (Propane) (lso.Butane) (n.Butane) Figure 18. G/L Chromatographic Analysis of Aerosol Grade Isobutane Supplier's analysis: 0.01% ethane, 1.91% propane, 96.08% isobutane and 2.00% n-butane (June 30,1980). Note: The arrow indicates a possible peak for ethane, not integrated in the illustrated analysis. Table XX Laboratory Results Accompanying Isobutane Shipments (From four major Aerosol Grade suppliers) Attribute C2 Ethane** C3 Propane IC« Isobutane NC4 N-butane C5 + (Isopentane, etc.) Unsaturates Sulfur Moisture Residue (g/100 ml) Acidity of Residue Pressure (psig at 70°F) Odor A 0.01 1.91 96.08 2.00 0.00 < 0.0003 0.0001 < 0.00012 0.0001 Neutral 31.95 Pass Compan; B 1.29 97.13 1.58 31.5 7 c 0.33 96.30 3.37 Trace 30.9 Pass D.* 0.01 99.97 0.02 31.0 Pass 'Supplier does not provide analyses. Tests performed by filler. **GLC results supplied as mol.% and liquid volume %. Converted to mol.% throughout, for uniformity. Note: All four lots approved by the filler as excellent quality. In a survey of 100 lots of Aerosol Grade isobutane, the highest level of propane was 2.26% and the highest level of n-butane was 3.75%. The two lowest isobutane assays were 94.37% and 95.43%.
344 The Aerosol Handbook measured as 248.2 kPa at 23.9°C would change to a pressure of 218.5 kPa at 21.1 °C, using a conversion factor of 10.6 kPa/°C.) A similar technique is used for measuring the specific gravity of bulk shipments. Prices are based upon U.S. Gallons at 60°F (15.6°C). For example, a standard tanktruck with a water capacity of 10,450 gallons is 79v% loaded with 8,255 gallons of iosbutane at a temperature of 75°F (23.9°C). Using a temperature conversion factor of 0.981 the volume is changed to 8,098 gallons at 60°F (15.6°C). If the truck is weighed before and after unloading payment is made according to weight loss, converted to U.S. Gallons at 60°F (15.6°C) by dividing the weight loss in pounds by 4.6937 pounds of isobutane per gallon at that temperature. Chemical tests are rarely performed during inspections of hydrocarbon propellents. If a chlorine or hypochlorite bleach type odor is detected, it may be due to tertiary butyl hydroperoxide (CH3)3COOH, produced in situ by Grignard RMgCl or other types of reactions. A sophisticated laboratory can detect this contaminant by GLC procedures, but wet-method testing for peroxide moieties is often sufficient in assigning cause. If acetylene is suspected for any reason, the same philosphy applies. It can be determined by GLC instrumentation, but also by the simpler procedure of bubbling the gas liquid through ammoniacal copper (I) or silver (I) solutions to precipitate the sparingly soluble metallic acetylides. (Caution! These are explosive when dry and should be destroyed with acid.) Properties of the Aerosol Grade Hydrocarbons Over half of the total consumption of aerosol hydrocarbons is in the form of the individual gas liquids. For example, neariy all antiperspirants and many hair sprays use isobutane. On the other hand, n-butane is almost never used any more as a single propellent, due to the sensitivity of such products to variations in temperature. At one time the two largest volume window cleaners were pressurized with n-butane, since somewhat less was needed than with isobutane. But at temperatures below about 55°F (12.8°C) the air-free Table XXI Physical Properties of Purified Hydrocarbon Propellents Property Ethane* Propane Isobutane N-butane Isopentane* Formula Molecular Weight Vapor Pressure (psig at 70°F) Freezing Point (°F) (1 atm.) Boiling Point (°F) (1 atm.) Specific Gravity (liquid) (60°F) Specific Gravity (gas) (60°F) (Air = 1) Critical Temperature (°F) Critical Pressure (psig) Critical Density (g/ml) Flash Point (°F) Lower Explosive Limit (v% in air) Upper Explosive Limit (v% in air) Heat of Combustion (BTU/lb.) Dispersion (Gas at 1 atm and 70°F) From 1 g (ml) From 1 ml (ml) Solubility of Water in Propellent (70°F) Solubility of Propellent in Water (70°F) (w% at 1 atm) C2H6 30.06 543 -297.8 -127.5 0.35 1.02 90.1 707.1 0.203 <-200 3.12 15.0 22,190 793 276 est. 0.0'31 0.008 VJ3-H-8 44.09 109.3 -305.9 -43.7 0.508 1.55 206.2 616.1 0.220 -156 2.20 9.51 21,620 540.2 272.3 0.0168 0.0079 C4H10 58.12 31.1 -255.3 10.9 0.563 2.01 274.8 528.1 0.221 -117 1.78 8.40 21,298 414.0 229.3 0.0088 0.0080 CiHio 58.12 16.92 -216.9 31.1 0.584 2.08 305.6 550.1 0.228 -101 1.84 8.48 21,318 400.6 233.9 0.0075 0.0080 C5H12 72.15 -3.5 -255.8 82,2 0.620 2.61 370.0 482.6 0.234 <-60 1.39 7.97 21,102 na na 0.0063 0.0084 •Usually considered as co-propellents — present in commercial propellents. Next Page
344 Previous Page The Aerosol Handbook measured as 248.2 kPa at 23.9°C would change to a pressure of 218.5 kPa at 21.1 °C, using a conversion factor of 10.6 kPa/°C.) A similar technique is used for measuring the specific gravity of bulk shipments. Prices are based upon U.S. Gallons at 60°F (15.6°C). For example, a standard tanktruck with a water capacity of 10,450 gallons is 79v% loaded with 8,255 gallons of iosbutane at a temperature of 75°F (23.9°C). Using a temperature conversion factor of 0.981 the volume is changed to 8,098 gallons at 60°F (15.6°C). If the truck is weighed before and after unloading payment is made according to weight loss, converted to U.S. Gallons at 60°F (15.6°C) by dividing the weight loss in pounds by 4.6937 pounds of isobutane per gallon at that temperature. Chemical tests are rarely performed during inspections of hydrocarbon propellents. If a chlorine or hypochlorite bleach type odor is detected, it may be due to tertiary butyl hydroperoxide (CH3)3COOH, produced in situ by Grignard RMgCl or other types of reactions. A sophisticated laboratory can detect this contaminant by GLC procedures, but wet-method testing for peroxide moieties is often sufficient in assigning cause. If acetylene is suspected for any reason, the same philosphy applies. It can be determined by GLC instrumentation, but also by the simpler procedure of bubbling the gas liquid through ammoniacal copper (I) or silver (I) solutions to precipitate the sparingly soluble metallic acetylides. (Caution! These are explosive when dry and should be destroyed with acid.) Properties of the Aerosol Grade Hydrocarbons Over half of the total consumption of aerosol hydrocarbons is in the form of the individual gas liquids. For example, nearly all antiperspirants and many hair sprays use isobutane. On the other hand, n-butane is almost never used any more as a single propellent, due to the sensitivity of such products to variations in temperature. At one time the two largest volume window cleaners were pressurized with n-butane, since somewhat less was needed than with isobutane. But at temperatures below about 55°F (12.8°C) the air-free Table XXI Physical Properties of Purified Hydrocarbon Propellents Property Ethane* Propane Isobutane N-butane Isopentane* Formula Molecular Weight Vapor Pressure (psig at 70°F) Freezing Point (°F) (1 atm.) Boiling Point (°F) (1 atm.) Specific Gravity (liquid) (60°F) Specific Gravity (gas) (60°F) (Air = 1) Critical Temperature (°F) Critical Pressure (psig) Critical Density (g/ml) Flash Point (°F) Lower Explosive Limit (v% in air) Upper Explosive Limit (v% in air) Heat of Combustion (BTU/lb.) Dispersion (Gas at 1 atm and 70°F) From 1 g (ml) From 1 ml (ml) Solubility of Water in Propellent (70°F) Solubility of Propellent in Water (70°F) (w% at 1 atm) C2H6 30.06 543 -297.8 -127.5 0.35 1.02 90.1 707.1 0.203 <-200 3.12 15.0 22,190 793 276 est. 0.0'31 0.008 VJ3-H-8 44.09 109.3 -305.9 -43.7 0.508 1.55 206.2 616.1 0.220 -156 2.20 9.51 21,620 540.2 272.3 0.0168 0.0079 C4H10 58.12 31.1 -255.3 10.9 0.563 2.01 274.8 528.1 0.221 -117 1.78 8.40 21,298 414.0 229.3 0.0088 0.0080 CiHio 58.12 16.92 -216.9 31.1 0.584 2.08 305.6 550.1 0.228 -101 1.84 8.48 21,318 400.6 233.9 0.0075 0.0080 C5H12 72.15 -3.5 -255.8 82,2 0.620 2.61 370.0 482.6 0.234 <-60 1.39 7.97 21,102 na na 0.0063 0.0084 •Usually considered as co-propellents — present in commercial propellents.
Aerosol Propellents 345 pressure sank below 9 psig (62 kPa) and the spray deteriorated to one with a streaming center. The physical properties of the purified hydrocarbon propellents are given in Table XXI. The only ones of real importance to the formulator are the pressures, densities and flammability. As a consequence, supplementary information on pressures is provided in Figure 19., and data on the variation of density with temperature is shown in Figure 20. The degree of flammability can be measured in terms of BTU/lb. (as one of several criteria). The BTU values of the hydrocarbons are very high, and they are compared with those of the lower alcohols and other important aerosol ingredients in Table XXII. Ethane is a relatively high pressure gas, now used only because it is a co-propellent almost always found in propane. It has no odor and is completely inert physiologically. It is available in states of high purity, since the only practical contaminants, methane and ethylene, are considerably more volatile. It may be purchased in five-foot cylinders, but the propellent suppliers continue to state that they have no plans to sell ethane in larger vessels. One intriguing idea has been to "beef up" Aerosol Grade propane by the addition of up to about 7.6w% ethane. This would act to elevate the pressure to 156.0 psig at 70°F (1.076 MPa at 21.1°C) which is the same as Polymerization Grade propylene. Table Thus, such a blend could be transported in tankcars like propylene, but higher pressure compositions could not. Theoretically, such a blend should be about 3.5% less costly than propane. It should also possess about 16 to 20% more dispersive power, depending upon the properties of the aerosol concentrate. Ethane has been used in the formulation of a number of experimental aerosol products, often with satisfactory results, but these have come to nothing because of both the supply problem and the fact that it could usually be replaced with either carbon dioxide or nitrous oxide, which have pressures about 44% higher than ethane and solubilities about 25 to 30% lower. Ethane would have to be introduced into aerosol units using instantaneous impact gassing techniques on either T-t- V or U-t-C gassing equipment, unless an explosion- proof gasser-shaker was available in a suitable enclosure. Propane is a fairly high pressure propellent and is used either pure or in blends whenever a propellent pressure of greater than 31 psig at 70°F (214 kPa at 21.1°C) is needed. Outside the U.S.A. it is sometimes used at concentrations of about 8 to 9%, with a preponderance of P-11 and concentrate levels of 10 to 20%, in order to give non-flammable sprays of excellent break-up. At least 30 to 35% P-12 would be required for the same dispersibility. Propane is also XXII Heat of Combustion for Various Aerosol Ingredients Molecular Kg-cal. Kg-cal. Ingredient Weight 30.05 44.06 58.08 72.15 86.21 100.22 114.24 128.26 142.29 156.31 32.03 46.05 60.10 46.05 58.08 84.93 BTU/lb. 22,190 21,620 21,298 21,152 20,887 20,741 20,601 20,471 20,376 20,304 10,238 13,309 14,390 13,586 13,226 2,262 100 g 1226 1195 1183 1163 1150 1144 1140 1137 1132 1128 533.5 711.4 799.5 754.8 734.8 125.7 BTU/gMW 1463 22089 2728 3328 3930 4552 5171 5789 6392 6999 679 1300 1908 1380 1694 424 gMW 368.4 526.3 687.2 838.3 989.9 1146.5 1302.7 1458.3 1610.2 1763.1 170.9 327.6 480.5 347.6 426.8 106.8 Ethane Propane iso-Butane Pentane Hexane Heptane Octane Nonane Decane* Undecane** Methanol Ethanol isoPropanol Dimethyl Ether Acetone Methylene Chloride Heats relate to combustions initiated at 20°C and one atmosphere, resulting in gaseous CO2, liquid H2O and heat. Hydrocarbons through pentane, as well as dimethyl ether are burned in the gas state. 'Corresponds to mineral spirits or light kerosenes. •'Corresponds to standard kerosenes.
346 The Aerosol Handbook used in conjunction with combinations of about one- part methylene chloride and three-parts 1,1, 1-trichloro- ethane (and up to 10% active materials) to produce heavy, residual sprays (at about 10%) or typical space sprays (at about 16%). A number of automotive products use propane as the propellent, because it is able to disperse heavy oils, greases, undercoatings and similar concentrates when used at 12 to 20% levels. Propane, along with the butanes and pentanes, is characterized by non-polarity, a total lack of hydrogen bonding, and very poor solubility in conjunction with polar substances, such as water, glycols, certain hair spray fixatives and many perfume ingredients. One measure of solvency is Kauri-Butanol value: a measure of incompatibility with a solution of Kauri resin in n-butyl alcohol. This is an old test and the results are somewhat artificial, but still used widely. A more fundamental measure of solvency is the solubility parameter concept, developed in 1916. It is a measure of Keesom (hydrogen bonding) forces and other forms of molecular attraction. When substances have similar solubility parameter values, they are usually miscible. Where a solution has a solubility parameter value close to that of an aerosol sealing gasket, there will most likely IMMISCIBLE REGION ko.butane 10 20 30 40 50 60 70 80 90-*-ethanol compositions are in weight percent Figure 21. Solubility of the EtHanoi, Water and Isobutane System at 70°F (21.1°C) be severe valve leakage and elastomer swelling, regardless of hydrogen bonding capacities. The K-B and S-P values for propane and other hydrocarbons are included in Table XXIII. 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 TEMPERATURE (<>F) 0.590 0.580 0.560 0.550 0.540 0.530 0.520 0.510 -0.500 a \ * 0.480 CO Z 0.470 Q 0.460 0.450 0.420 kli ": i ; ii i | i i i i ! . i>m ! : i i ! 1 j 1 ! Ml! 1 . Sv^ i ! ! j 1 \! ' Nv, N. BUTANE . >\ ' ■■ : |S|.. j 1 ; ' N - - 1 I i ! 1 ! ; 1 ' Xi ! , . | | i ■■ ■ i ' >Sj • ! i , , ! i i . "V^ ^Nv— 1 1 1 1 1 i L ' ' 1 : ! ; ' . ' N^ 1 1 1 • \ 1 ISO. BUTANE ^v ' N. ! 1 . 1 . , . Xl V ' 1 X. < 1 i 'II!' :Xpropane 1 ' ■ i ■ "N. 1 ! 1 i i j 1 1 j i ; 1 [ ■ ! ! | 1 : ! ! i i ; ' X >V 1 I ' \l 1 1 l ■ i i i ; ; : Mi _i. ! 1 ; ! i : .lV , ■■ : i ■ .. .; Li i . 11 ! ; I , . i\ ' : ' • ' ■ 1 ■ j ! i '■ . ' 1 i ' ' i\ ■ i ■ ' ■ I i ! i i i i II ' 1 ' i i : \ ■ : ' l i III: ' M I ! ■ 1 III 1 1 ! I "- ; "m ; ■ ' ■ IV ■ ' ; II I \l ! 1 i 1 1 1 ; \ 1 ' : i ' I 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 TEMPERATURE (°F) Figure 19. Pressure of Hydrocarbon Propellents at Various Temperatures Figure 20. Density of Hydrocarbon Propellents at Various Temperatures
Aerosol Propellents 347 Propane and the butanes are essentially insoluble in water. However, modest percentages of water can be included in such products as disinfectant/deodorants and hair sprays by taking advantage of the co-solvent effect of ethanol. For example, if 69.5% ethanol is present in a formulation, the remaining 30.5% of water and propane can consist of any ratio of these two components and remain as a one-phase solution at 70°F. For isobutane/ethanol/water systems, those with over 68.0% ethanol are miscible and in the case of n-butane/ ethanol/water compositions, ones with over 68.8% ethanol are always soluble. This relationship is illustrated in the case of isobutane/ethanol/water by means of a triangular graph, Figure 21. Isobutane is the workhorse of the hydrocarbon propellents, often used in a non-blended form, since the pressure of about 31 psig at 70°F (214 kPa at 21.1 °C) is sufficient for many applications. Although the distinction is more or less academic, isobutane (and n-butane) may be considered slightly more flammable than propane. They have lower LELs, and the vapors are heavier and tend to collect in floor level areas more readily. Comparing the combustion equations: C3H8(propane) + 502 - 3C02 + 4H20 C4HI0(butane) + 6.502 - 4C02 + 5H20, Table XXIII Solvent Properties of Propellents and Other Substances Substance Propane Isobutane n-Butane Isopentane Mineral Spirits P-ll P-12 P-22 P-113 P-114 P-142b P-152a P-C318 Dimethyl Ether Methylene Chloride Chloroform Carbon Tetrachloride Ethanol Isopropanol n-Butanol MEK MIBK Butyl Acetate Butyl Cellosolve Toluene Xylenes BunaN Neoprene GN Butyl Rubber Natural Rubber Polyethylenes General Solvency Poor Poor Poor Poor Poor Good Poor Fair Fair Poor Good Good Very Poor Very Good Excellent Excellent Excellent Very Good Very Good Good Very Good Very Good Very Good Very Good Very Good Very Good na na na na na Hydrogen Bonding 0 0 0 0 0 0 0 Fair 0 0 Low Low 0 High Good Good 0 High High Fair High High High High * ** ** * ** Kauri-Butanol Value 15.2 17.5 19.5 21.3 34-40 60 18 25 31 12 20 11 10 91 136 208 113 105 95 na na na na na Solubility Parameter 7.1 7.1 7.1 7.1 7.2 7.5 6.1 6.5 7.2 6.2 6.8 7.0 5.0 7.3 9.5 9.1 8.6 12.8 11.9 11.4 9.3 8.4 8.4 8.9 9.4 9.2 8.1 8.3 7.4 Notes: Substances having similar solubility parameters will usually be miscible. Where solutions have solubility parameters near those of valve elastomers pronounced swelling and valve leakage may result, regardless of hydrogen bonding capabilities. *High hydrogen-bonding capacity. * "Low hydrogen-bonding capacity. ""Zero hydrogen-bonding capacity, except for certain parameters.
348 The Aerosol Handbook The isodiermal increases in gas volume are 17% and 20%, respectively. In a closed space, this would give only a slight increase in pressure. The large pressure increase noted during fires or explosions is due mainly to die temperature effect. At die LEL, for instance, 1.8v% of isobutane will combine widi 11.5v% of oxygen in a chemical reaction generating intense heat. This heat instantly dissipates through the 86.7v% of non- reacting molecules (mainly nitrogen) in die mixture and causes an immediate expansion to several times die original gas volume in accordance with Charles' Law. If there is an impediment to diis expansion, then the pressure will increase and die impediment (such as a room or building) may or may not give way. When the isobutane concentration increases beyond 3.0% it is then capable of reacting widi all the oxygen in die gas mixture and must then reach beyond the immediate reaction locale to find additional oxygen. Reactions at supra-LEL levels are substantially more violent dian diose at die LEL, with bodi flame travel rate and fireball size being magnified. When die pressure increase gets to more than 0.04 psi (0.28 kPa) windows may blow out, roofs may bulge and odier things may happen in the resulting "whoosh". At less than this level die pressure increase may be felt only in the ears. The key to all this is the relationship of the amount of flammable gas mixture to die size of the enclosure, and, to some extent, the sturdiness of the construction. Isobutane is the most common propellent for anti- perspirants, window cleaners, starches, hair sprays and a host of other aerosol products. Many aerosol fillers use it also in die production of lighter fluids and refill tubes. For paints, shaving creams and other applications where higher pressure propellents are needed, isobutane is commonly blended with propane, by eidier the supplier or the filler, using explosion-proof proportioning blending equipment. n-Butane is rarely used in die pure form, but it does find a minor place in the production of some colognes and perfumes, being used at about 16% to 20% of such formulations. Its low pressure of 17 psig at 70°F (117 kPa at 21.1°C) makes die spray pattern susceptible to deterioration at temperatures below 55° to 60°F (13 to 16°C). Nearly all die n-butane diat finds its way into aerosols does so in the form of blends: up to about 4% in compositions high in isobutane, and up to 60% in blends of propane with the unseparated butanes, as is discussed later. Isopentane is the last hydrocarbon propellent of any significance. Since it has a boiling point of 82.2°F (27.9°C) it is a very volatile liquid and not a true propellent. It occurs as a co-propellent in certain commercial and Aerosol Grade blends, particularly those of propane and die natural butane mixtures, where it may get as high as 3.0%. In die pure form it is used as a latent puffing or foaming agent in certain Sepro-can type shaving creams. There are two major roadblocks that must be overcome before isopentane can be a higher volume aerosol ingredient: odor, and its unique flammability hazards. The highly purified material can be purchased in tankcar or (at least formerly) tanktruck quantities, but not as an Aerosol Grade material. One supplier will (somewhat reluctandy) spot-check die odor level of available tankcars and ship the lowest ones to interested aerosol customers, who may or may not have dieir own purification towers. The odor level of hand-picked, good quality lots of Commercial Grade (gasoline grade) isopentane is generally very close or even equal to diat of the purified material. The odor of the hydrocarbon itself is slightly higher uian diat of isobutane, but comparable with diat of n-butane. Except under rather unusual circumstances the odor of isopentane is not a formulating problem. Because isopentane is such a volatile and flammable liquid it has been treated as a true propellent in filling plants. Using sealed systems, the material is pressure loaded into containers using T-t-V or U-t-C techniques. But, even here it is felt that isopentane may pose an extra or even unacceptable level of hazard, due to the fact that it is essentially a liquid substance. For instance, a rupture of a 600 to 800 psig (4.14 to 5.52 mPa) isopentane hose in the gas house could act to release a radier large amount of liquid before a sufficient quantity of gas is produced, so diat the detection system would sense it and react by electrically activating the interlock circuitry. If a fire was initiated die fuel pool on die floor could sustain it, in spite of some of the sprinkling systems now in use. Such a situation would not occur with propane or the butanes, since they would not form liquid pools unless very cold (and non- warmed) propellent supplies were being used. Isopentane has been used in at least a million cans of hair spray, widi typical formulations consisting of about 5.5% C02, 15% isopentane, 12% methylene chloride and 67.5% emanolic concentrate. They provided extraordinarily good spray patterns at all stages of use,
Aerosol Propellents 349 but were discontinued in favor of formulas that were safer for the plants to produce. The "fuel pool" disadvantage of isopentane is eliminated if the material is brought into the gas house as a blend with propane. Since isopentane is only slightly higher in price than propane, such blends are economically attractive. Some filling has been done with such blends. The so-called distillation effect, where propane would preferentially escape from the liquid phase, is not a problem, provided the propane content of the total formulation is over 10 to 12 % and a non vapor-tap valve is used. Certain higher pressure propane/isopen- tane blends can be used with vapor-tap systems. In any case, since the propellent suppliers do not blend isopentane with Aerosol Grade propellents, such mixtures have to be produced by the fillers themselves. Blends of Hydrocarbon Propellents Almost half of the hydrocarbon aerosol market is held by blended gas liquids. The oldest and still the most common mixtures are combinations of propane and isobutane, giving pressures which range from 31 to 109 psig at 70°F (214 to 752 kPa at 21.1°C). The lower pressure blends of this series are the most popular. The propane isobutane mixtures are most commonly identified in the U.S.A. by designations such as A-36, A-40, C-70, C-85 and so forth. The "A" stands for Aerosol Grade and the "C" stands for Commercial Grade. The number which follows signifies the pressure at 70°F (21.1 °C), with a pressure specification generally ± 2 psi (14 kPa) from that figure. The various "A" type designations, such as A-36, were copyrighted with the U.S. Patent Office by Phillips Petroleum Co. during the 1950's, when they pioneered the Aerosol Grade products and blends. The terms became very popular and are used generically by almost everyone in the aerosol industry. That liberty is taken here, for simplicity, but recognizing that they are Phillips Petroleum Co. trademarks and that the industry owes this company much for their foresighted investment into specially purified aerosol propellents that are so important to us today. Outside of the U.S.A. and Canada, these blends are identified by stating the ingredients and the pressure in bars at 20°C (68°F); for example: propane/isobutane, 2.7 bars. This mixture is the equivalent of A-41.7 in the Phillips Petroleum Co. designation, assuming the hydrocarbons are in a purified state. Propane/isobutane blends are also identified in terms of mol%, volume % and weight % by the suppliers, and this has led to a great deal of confusion in the filling segment of the industry. Since weight is the basis on which virtually all aerosols are formulated and filled, various supplier data expressed in mol% and volume % must be laboriously converted to weight % in order to be meaningful. Charts and graphs are available to help make the conversion, and a short summary of the interrelationship is provided here as Table XXIV. The table is idealized, as if only mixtures of ultra- pure propane and isobutane were involved, when actually up to 5% of other hydrocarbons can be present within the scope of the Aerosol Grade specification. Thus, a typical composition for A-46 might be 0.08% ethane, 19.59% propane, 78.34% isobutane, 1.97% n-butane and traces of other components. The pressure of several standard blends is given at various temperatures in Figure 22 and the density versus temperature relationships of the same mixtures are shown in Figure 23 (Page 350). Blends have been made commercially using isobutane and n-butane. Of these, only A-24 is significant, but others include A-20, A-28 and A-29. They are of some interest in the formulation of glass aerosol products. Table XXIV Conversions Between Mol, Volume and Weight Per Cent for Blends of Propane & Isobutane Pressure Pressure Propane Content (psig 70 °F) 31.1* 34.0 40.0 46.0 52.0 59.0 62.0 67.0 70.0 76.0 80.0 85.0 92.0 96.0 109.1** (kPa21°C) 214 234 276 317 359 407 427 462 483 524 552 586 634 662 754 Mol% 0 3.8 11.4 19.0 26.8 35.6 39.5 45.9 49.8 57.3 62.5 68.9 77.9 83.0 100.0 Volume % 0 3.2 9.8 16.5 23.5 31.7 35.5 41.7 45.5 53.1 58.4 65.1 74.8 80.4 100.0 Weight % 0 2.9 8.9 15.1 21.7 29.6 33.1 39.2 41.9 50.6 55.8 62.7 72.8 78.7 100.0 'Aerosol Grade isobutane; known as A-31. "Aerosol Grade propane; known as A-108. AH other compositions are standard industry blends now in commercial use, e.g. A-34, A-40, A-46, etc.
350 The Aerosol Handbook About 1979 the n-butane/propane series of propellent blends became commercially important. They had always been available, but in 1979 they were starting to be priced lower than comparable pressure isobutane/propane mixtures. This was a reflection of the considerably lower price tag for field grade n-butane, compared with field grade isobutane. It was inappropriate to call these blends by the A-17 to A-108 type designations, since this would invite confusion with the standard isobutane/propane compositions. As a result, a series of other terms were developed. For example, the 46 psig at 70°F (317 kPa at 21°C) blend became known as Aeropres B-46, Aeron NP-46 (Diversified), Propellent BP-46 (Phillips), and so forth. At least nine of these n-butane/propane blends have been sold commercially. A listing of stylized compositions (as if they contained only ultra-pure n-butane and propane) is provided in Table XXV, along with pressure and density figures for 70°F and 130°F (21.1°Cand54.4°C). An examination of these mixtures as possible replacements for isobutane or isobutane/propane blends shows that they do not have quite as much dispersant ability. This minor shortcoming can be corrected by using about 1.08 times as much propellent in 350 300 250 a. w200 w « 180 D S 160 W ? 140 120 100 80 60 40 20 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 TEMPERATURE <°F) Figure 22. Pressure of Propane/lsobutane Propellents at Various Temperatures [/■ y s A- A A 1( -4 -.< 8, U / / / f the formula, or by revising the composition to the next higher pressure level. (Intermediate blends can be supplied as easily as the standard ones, if needed.) The higher pressure approach is generally the easiest for the formulator. Any slight increases in delivery rate can be removed by selecting a valve with a slightly smaller rate-limiting orifice size. As the amount of propane in the n-butane/propane blends increases, there is less and less need for such adjustments, since the n-butane, which causes the differences, is diluted into relative insignificance. During the spray-down of any aerosol composition, except an air-free ultra-pure single propellent, the pressure moves downward, rather fast at first as head space air is diluted, and then more slowly, due mainly to evaporation of propellent out of the liquid phase into the expanding head space. If the propellent consists of a blend, the pressure decreases during use at a rate somewhat greater than is the case for a single propellent. Where the formulation contains a relatively high percentage of propellent, the distillation effect is reduced, since the liquid composition is changed less by evaporation of the most volatile components into the enlarging head space. 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 TEMPERATURE (°F) Figure 23. Density of Propane/lsobutane Propellents at Various Temperatures
Aerosol Propellents 351 This is illustrated by taking a standard anhydrous hair spray as an example, where the commercial formulation consists of a concentrate, plus 20% A-31. By substituting a blend of n-butane/propane (31 psig 70 °F for 214 kPa at 21 °C) for the isobutane, the pressure will decrease during use as shown in Table XXVI. The delivery rate drops significantly and the quality of the spray deteriorates during the second half of the can spray out. By using a higher pressure blend of n-butane/propane the quality of the spray pattern is improved, but changes in delivery rate. Relative fineness of the particles still change as a result of the selective evaporation of the rather small propane inventory. The n-butane/propane blends in the range of B-70 to B-90 work much more satisfactorily, and are virtually indistinguishable from the regular A-70 to A-90 blends. They are used to a significant extent in paint and coatings, and in several automotive products. The use of vapor-tap valves places an additional strain on the n-butane/propane blends, since propane is lost not only to the expanding headspace, but to the atmosphere as well, through the valve vapor-tap orifice. Such valves should be used with n-butane/propane blends only when the relative amount of propane is reasonably high, and when the percentage of propellent blend is rather high as well. Before leaving these blends, a small economic aspect should be noted. Considering A-31 and B-31 as an example, the density of A-31 is 0.564 at 60°/60°F (15.6°/15.6°C), while that of B-31 is 0.5736 at the same references. The difference in density is 1.7%. Since hydrocarbons are purchased by the gallon and sold by the pound, there is an additional economic incentive of 1.7% (roughly $0.02/gallon) to purchase B-31 instead of A-31. However, as greater amounts of propane are included in the "B-" blends, the incentive becomes less. In June, 1980, after about two years of research and preparation, Aeropres Corp. introduced their Aeropin blends. They are prepared from combinations of propane with naturally occurring n-butane/isobutane Table XXV Composition and Physical Properties of n-Butane/Propane Propellent Blends Propellent Blend B-24* B-31 B-40 B-46 B-59 B-70 B-80 B-85 B-90 Mol% 8.0 16.0 25.0 31.7 44.7 57.5 68.3 73.7 79.0 Propane Level Wt.% 6.2 12.6 20.2 26.1 38.0 50.7 62.1 68.0 74.1 70 °F 24 31 40 46 59 70 80 85 90 Pressure (psig) 130 °F 81.4 96.1 114.4 126.4 153.0 176.3 198.0 207.2 219.0 Density (g/ml) 70 °F 0.570 0.565 0.558 0.553 0.543 0.535 0.527 0.522 0.517 130 °F 0.530 0.523 0.513 0.506 0.494 0.485 0.474 0.467 0.459 *Aeropres B-24, Aeron NP-24 (Diversified), Propellent BP-24 (Phillips), or like blend from other propellent suppliers. The same for other propellent designations. Table XXVI Decrease in Pressure as Aerosol Hair Spray is Discharged (For hair spray, with 20.0% propellent.) Propellent 25 Pressure (psig at 70°F or 6.89 kPa at 21°C) Per Cent of Product Dispensed 50 75 A-31 B-31* BI-31" BI-34 BI-36 30 30 30 33 35 23 19 20 22 23.5 22 16 17 20 22 20 14 16 18 20 17.5 12.5 14.5 16.0 17.0 •Aeropres B-31, Aeron NP-31 (Diversified), Propellent BP-31 (Phillips), etc. **Aeropin 31 (Aeropres), Aeron NIP-31 (Diversified), Propellent IBP-31 (Phillips), etc. Approximately 8w% propane, 37w% isobutane and 55w^ n-butane.
352 The Aerosol Handbook stocks. These stocks may contain up to about 3 mol% isopentane, so this co-propellent must be considered also. The economic attraction is that the distillation step used normally to separate the isomeric butanes need not be conducted. The Aeropin butanes are drawn from east Texas gas wells where the concentration of isobutane is unusually high, approximately 40.0 w% of the total butanes content. The Aeropin propellents start Table with Aeropin-24 and then, by adding increasing amounts of propane, they extend upward to Aeropin-70. By 1981 other hydrocarbon suppliers also offered equivalent series of propellent blends. The Phillips products were called Propellents A-(number) IBP and the Diversified blends were designated Aeron NlP-(number), for example. A comparison of the compositions of A-46, B-46 and BI-46 propellents is provided in Table XXVII. XXVII Typical Compositions for Hydrocarbon Propellent Blends Having a Gauge Pressure of 46 psig (3.22 kg/cm2 or 317.1 kPa) At21.1°C(70°F) Ingredients Propellent A-46* Aeropres 46** Aeron A-46*** Per Cent by Weight Propellent A-46*BP Aeropres B46** Aeron NP-46*** Propellent A-46'IBP Aeropin 46** Aeron NIP-46*** Ethane Propane Isobutane n-Butane Pentanes Hexanes Unsaturated Hydrocarbons Sulfur Compounds Water 0.08 19.59 78.34 1.975 0.010 0.001 0.001 (max 0.0005 (max 0.0025 (max •) ■) •) 0.25 26.00 2.00 69.236 2.500 0.010 0.001 (max 0.0005 (max 0.0025 (max •) •) •) 0.29 21.67 30.09 45.236 2.700 0.010 0.001 (max.) 0.0005 (max.) 0.0025 (max.) *Trademark of the Phillips Petroleum Company. "Trademarks of the Aeropres Corporation. "Trademark of the Diversified Chemicals and Propellents Co. Table XXVIII Typical Compositions of the Aeropin Propellents (Considering only propane, isobutane and n-butane) Propellent Aeropin-24* Aeropin-29 Aeropin-31 Aeropin-46 Aeropin-52 Aeropin-70 Density (60 °F) 0.5742 0.5708 0.5696 0.5591 0.5547 0.5411 Composition 1.65 6.19 8.03 22.27 28.34 47.93 Propane - Isobutane - ■ N. Butane (Weight Percent) 39.29 37.53 36.78 31.09 28.67 20.83 Typical 58.96 56.28 55.19 46.64 42.99 31.24 •Registered trademark of the Aeropres Corp. Typical Compositions of the Phillips BIP Propellents Propellent A-31* BIP A-46* BIP A-70* BIP A-80* BIP A-85* BIP Ethane 0.0 0.0 0.0 0.0 0.0 Propane 9.0 22.2 47.7 60.6 66.9 Composition i (Weight Per Cent) Typical** Isobutane 36.1 30.9 20.7 15.7 13.1 n-Butane 54.2 46.4 31.3 23.5 16.8 Pentanes 0.7 0.5 0.3 0.2 0.2 "Registered trademarks of the Phillips Petroleum Co. * "Specification maximums for ethane = 1 mol%, and for pentanes = 1.5 mol%.
Aerosol Propellents 353 The BI- propellents (propane, isobutane/n-butane blends) are true Aerosol Grade products. The saturates content is above 99.99 mol%, and unsaturates are below 0.001 %. Moisture is below 25 ppm and typically 1 ppm. Sulfur is below 5 ppm and typically below 1 ppm. Residue, acidity of residue, odor and so forth are comparable to the Aerosol Grade propane and iso- butane blends. Typical compositions of these new propellents are shown in Table XXVIII for two major suppliers. Compositions offered by other suppliers are equivalent. The pressure drop during use is greater than for the propane/isobutane blends, but less than for the propane/n-butane mixtures, as would be anticipated. Small orifice vapor-tap valves can be used for certain Table products, provided the percentage of propellent is rather high. It helps to have a higher pressure blend for these applications, to provide a greater inventory of propane for its preferential volatilization from the concentrate, which occurs during use. A marginal situation is encountered in the case of antiperspirant formulas, which commonly contain about 68 to 74% propellent, but where lower pressure types are used, principally isobutane or sometimes A-40. The data presented in Table XXIX represents results obtained in a study conducted on a commercial antiperspirant. To complete the discussion of hydrocarbon blends, the combination of propane and isopentane is mentioned, again with the caution that it is theoretically very inexpensive, yet not readily obtainable on a commercial basis. In this case, because of the wide XXIX Effect of Propellent Selection on the Properties of a Typical Antiperspirant Propellent A-31* A-31** Aeropin-31 Aeropin-34 Aeropin-36 Aeropin-40 Aeropin-46 Initial Delivery Rate (g/»0 0.61 0.60 0.61 0.63 0.64 0.66 0.69 Initial Flame Prog'n. (in.) 19 19 19 20 21 22 24 Initial Spray Pattern Diameter ("at 7") 1.5 1.5 1.5 1.7 1.8 1.7 1.9 Delivery Total (g-) 114.9 115.0 116.5 117.1 116.3 116.8 116.2 Residual Weight (g0 2.3 2.1 1.3 1.5 1.7 1.5 0.9 Initial Solids Transfer Efficiency 48.8% 48.0% 48.7% 49.6% 48.0% 47.2% 43.1% 100% 34 33 36 38 40 45 51 Pressure - 70 °F (ai. P"g. l°C) Fill Amounts 75% 32 30 30 33 35 38 45 50% 31 29 28 31 32 37 41 25% 30 27 27 29 29 34 38 "Production control units - vacuum crimped at 200 "Hg°. 'Laboratory control units - vacuum crimped at 20" Hg° Notes: a. All results represent the average of six cans tested. b. The spray pattern of units pressurized with Aeropres 34 and 36 most closely matched the particle size and pattern of the standards, throughout the life of the test cans. c. While Aeropin blends were selected in this test series, other propane/isobutane/n-butane blends of essentially the same composition should give fully equivalent results. Table XXX Composition and Pressures of Various PIP Propellents (Propane and isoPentane Propellent PIP-(-3) PIP-17 PIP-31 PIP-36 PIP-40 PIP-46 PIP-60 PIP-70 PIP-80 IsoPentane Content (wt%) 100 89 80 76 73 68 56 47 38 70 °F -3 17 31 36 40 46 60 70 80 Pressure (psig) 100 °F 6 32 50 59.5 65 74 95.5 111 127 130 °F 20.5 53 78 90 97 109.5 138 158 180.5 160IF 40 — — 126 135 149.5 179 — — Note: These blends were not commercially available in 1982; however, interested fillers might be able to mix their own requirements.
354 The Aerosol Handbook discrepancy in vapor pressure between the two component hydrocarbons, distillation effects can be expected to be at a maximum. The most useful of these blends are the higher pressure ones, used preferably at reasonably high concentrations in the total product. Table XXX provides composition and pressure data on these so-called PIP compositions. In a second study, this time involving an anhydrous insecticide high in 1,1,1-trichloroethane and carrying 30% of hydrocarbon propellent blend, particle size measurements were taken at the 100% full, 50% full and 25% full levels, to compare the break-up of the A-70 standard propellent with both a propane/iso- butane/n-butane (PIN-70) blend and the propane/iso- pentane (PIP-70) blend as the dispensers were emptied isothermally at about 70°F (21.1°C). The results of this Malvern type analysis are shown in Table XXXI and also in a particle size profile in the Aerosol Toxicology chapter, Figure 8. The data show that both the A-70 and PIN-70 propellents give comparable results, whereas the PIP-70 particulation is a bit coarser, but probably acceptable commercially, and undoubtedly correctable by changing to a higher pressure blend, such as PIP-80. Ether Type Aerosol Propellents These propellents are not yet commercialy significant in the U.S.A. or other countries in the Western Hemisphere, but one (dimethyl ether, or DME) has achieved fairly large scale use in certain European countries and in Japan. DME is said to account for 20% of the aerosol unit production in Belgium (1980), 17% of that in The Netherlands (1980) and 18% of the total in Japan (1979). About 22 million pounds (10,000 metric tons) were produced in Europe in 1980, account- Propellent Can Fill Mean Diameter (/un) A-70 A-70 A-70 Aeropin-70 Aeropin-70 Aeropin-70 PIP-70 PIP-70 PIP-70 1, 2&3 1, 2&3 1, 2 & 3 4, 5&6 4, 5&6 4&5 7 7 7 100% 50% 25% 100% 50% 25% 100% 50% 25% 25.63 29.25 36.25 22.18 30.88 30.62* 20.03 33.72 41.07 *Can 6 (25%) input deleted from average — appears to have developed vapor-tap characteristics. Table XXXI Particle Size Distribution of an Anhydrous Insecticide Spray (Malvern Analyser) (36% Hydrocarbon Propellent) Fill Propellent 0.5 1.0 6.0 Cumulative Weight of Particles Below: (/un) 10 20 30 40 50 60 70 1 1 1 2 2 2 3 3 3 4 4 4 5 5 5 6 6 6 7 7 7 100 50 25 100 50 25 100 50 25 100 50 25 100 50 25 100 50 25 100 50 25 A-70 A-70 A-70 A-70 A-70 A-70 A-70 A-70 A-70 Aeropin-70 Aeropin-70 Aeropin-70 Aeropin-70 Aeropin-70 Aeropin-70 Aeropin-70 Aeropin-70 Aeropin-70 PIP-70 PIP-70 PIP-70 .13 .04 .09 .18 .10 .21 .07 .14 .04 .30 .26 .16 .20 .25 .05 .18 .20 .41 .40 .33 .14 .42 .15 .27 .54 .35 .55 .24 .39 .13 .85 .69 .49 .61 .66 .19 .54 .58 .95 .93 .97 .50 8.4 4.6 4.7 9.1 7.0 6.6 4.9 5.6 3.2 11.7 8.1 6.5 10.3 7.8 4.5 9.1 8.2 7.9 13.2 9.4 6.3 19.0 11.7 10.3 19.5 15.9 12.9 11.2 11.7 7.9 23.6 15.9 12.5 21.8 15.3 11.0 19.5 16.7 14.1 25.3 18.0 14.1 49.6 37.1 28.1 48.2 43.1 30.6 32.0 29.8 25.0 53.2 36.7 30.0 53.0 35.5 33.4 48.2 40.4 29.5 61.1 35.2 35.4 74.4 63.2 46.8 71.6 67.5 47.5 53.7 47.8 44.9 75.3 55.3 45.9 76.0 53.9 56.9 71.6 61.4 43.4 82.3 52.9 54.1 91.1 82.2 63.2 88.4 84.0 61.9 71.5 63.2 63.2 88.4 70.0 60.1 89.6 68.6 75.7 86.4 76.9 55.2 89.1 67.0 67.6 96.1 92.9 76.0 94.2 93.1 73.3 84.0 75.3 77.6 95.0 80.7 72.0 96.0 79.5 87.9 94.2 87.1 65.0 96.3 79.8 81.3 98.8 97.6 85.2 97.8 97.4 81.8 91.8 84.1 87.4 98.0 88.1 80.2 98.7 87.0 94.7 97.8 93.2 72.9 97.9 90.1 87.3 99.7 99.3 91.4 99.2 99.1 87.9 96.1 90.1 93.5 99.3 92.9 86.4 99.6 92.1 97.9 99.2 96.6 79.2 99.2 91.6 89.0
Aerosol Propellents 355 ing for about 4.6% of all European aerosols. During 1979 the Japanese production amounted to about 13 million pounds (6,500 metric tons), going into about 60 million cans. DME was used by inventor Eric Rotheim of Norway as early as 1922 in preparing aerosol compositions. It was unavailable in the U.S.A. from several firms during the period 1950-1968, but then discontinued as a commercial item, although cylinder supplies could be ordered from specialty houses. In 1981 E.I. du Pont de Nemours & Co., Inc. entered the U.S.A. market with a highly purified material, made from a less purified form which they used internally as a reaction intermediate in the production of dimethylimide for making textile polymers. The price of DME during 1982 was $0.57/lb. ($1.26/kg) in bulk lots, f.o.b. plant. In Europe, the West German firm of Union Kraft- stoff, Gmbh. decided to purify their DME for aerosol uses at the request of a Dutch filler, Aerofako bv (AKZO), and this resulted in the 1966 introduction of the first DME aerosols: hair sprays, on the French market. With the recent expansion of the aerosol market for DME, Union Kraftstoff has increased the yield of their manufacturing process to provide a production capacity of up to 100 million pounds (45,400 metric tons) per year. The price of DME in Europe was said, to be in the order of $0.27/lb. ($0.59/kg) in mid-1982. DME is produced in Japan by four companies as a by-product of high pressure methanol synthesis. The market was said to have grown by 22% between 1979 and 1980, but supply is not viewed as a potential problem there. In Canada, production interest has been expressed by both CCL Industries Ltd. (Toronto) and Alberta Gas Chemicals Ltd. (Montreal). The latter cur- rendy is a producer of 99.85% methanol by high pressure synthesis in the province of Alberta. About 60% of the anticipated CCL Industries Ltd. production would be available for purchase.* Purity and Physical Properties of DME. The most effective manufacturing processes for DME begin with the reaction of bituminous or lignitic coals with steam to give water gas (CO, H2, CH4, etc.), which is then passed over finely divided nickel or an alternate catalyst at 660°F (350°C) and 450 psig (3.00 'The firm prefers to use the terms dimethyl oxide or DMO for this product, feeling that the word ether has an unpleasant connotation of flamma- bility, anesthesia and odor. MPa) conditions to form formaldehyde, which is then reduced to methanol and a small amount of DME. Depending upon conditions, these last two products can be reduced by the hydrogen to form methane and water, but this is not allowed to occur to any significant extent. Where the reaction is adjusted to give methanol as the final product, only about 1.5 to 4.0% of DME is formed as a by-product. But by minimizing the steam content and changing other process conditions the output of DME can be increased, to as high as 40% of the total. The propellent can be considered to be formed by the dehydration of methanol. The specifications for DME will vary depending to some extent upon the synthesis procedure, but more particularly upon the purification process. Specifications for European and U.S.A. products are given in Table XXXII. In the presence of oxygen (or air) and ultraviolet light, DME will slowly form a rather unique peroxide: H2C(OOH)OCH3. Since peroxides can be thermally or mechanically unstable, and have led to explosions in the case of diethyl ether and di-isopropyl ether, the significance of this reaction was studied in the case of DME. It has not been found to present a problem in either glass or metal containers, with DME alone or in formulated products. Conjecturally, this may be because ultraviolet radiation of a sufficiently short wavelength to cause peroxidation cannot penetrate the glass or metal dispenser. Another potential concern was the generation of bichloromethyl ether (BCME), which is considered to Table XXXII Specifications for Dimethyl Ether (DME) Specification Organic Purity Water Methanol Methane, ethane, propane & butanes Sulfur compounds Mineral oil Formaldehyde •Private communication: **Private communication. 0.2 ppm Du Pont 99.8%) min. 99.9% typ. 0.05%) max. 0.02% max. is typical. Union Kraftstoff 99.6% min. 99.8% typ. 0.05%) max. 0.001% max. 0.4%) max. 0.2% typ. 0.0001% max.* 0.003% max. trace** Although not stated in specifications, traces of acetone, ammonia and acetic acid may be present in the 0.001% range.
356 The Aerosol Handbook be a powerful carcinogenic compound. Some early data indicated 10 ppb of BCME in several aerosol formulas containing both DME and chlorinated compounds. However, later tests on formulas up to four months old showed no BCME, using special instrumentation with a threshhold sensitivity of 1 ppb. In fact, inoculated BCME formulas showed anywhere from slow to rapid decomposition of the added compound, due to reaction with water, ethanol or other polar ingredients. No BCME was formed upon spraying DME/chlorocarbon formulas into ultraviolet irradiated air, even after an hour of aging time and under humidities ranging from 0 to 57%. In this study the instrument had a sensitivity of 100 ppt (100 pg/g). The suggested BCME carcinogen problem can thus be dismissed as fiction. The physical properties of DME are provided in Table XXXIII. The propellent is a clear, water-white, virtually odorless liquid having a low viscosity and surface tension. It is unique among propellents in that it has a high solubility in water and functions as an excellent solvent for many other polar substances. See U.S. Patent 3,207,386 (Sept. 21, 1965). Table XXXIII Physical Properties of Dimethyl Ether (DME) Formula Molecular Weight Vapor Pressure at 70°F (21.1°C) psig Vapor Pressure at 130°F (54.4°C) psig Freezing Point Boiling Point Specific Gravity (liquid) at 68°F (20°C) Specific Gravity (gas) at 68°F (20°C) Air = 1 Critical Temperature Critical Pressure Critical Density (g/ml) Flash Point Lower Explosive Limit (v% in air) Upper Explosive Limit (v% in air) Heat of Combustion (BTU/lb) Auto-ignition Temperature Solubility of Water in DME at 68°F (20°C) and 63 psig (w%) Solubility of DME in Water at 68°F (20°C) and 63 psig (w%) Solubility of DME in Water at 68°F (20°C) and 1 atm. (ml gas/ml) CH3.OCH3 46.07 63.03 174. -217.3°F(-138.5°C) -12.7°F(-23.7°C) 0.66 1.617 231.6°F(126.9°C) 777.5 psig (5.361 MPa) 0.242 -42°F(-41°C) 3.4 18.2 13.586 660°F (350°C)* 5.84 34.17 36.5 ml/ml •West German sources report 455°F (235°C). The difference may relate to the tester or testing conditions used. Because DME is such a strong solvent, special precautions must be used in the selection of valve gaskets and crimping specifications. The formulator can have a lot of nasty surprises in these areas. Crimping specifications are suggested as 1.070 ±0.005" (27.18 ±0.13 mm) for diameter and 0.182 " (4.62 mm) maximum for crimp depth, except in the case of the Precision PE- sleeve cup gasket, where the differences in geometry suggest a crimp depth specification of 0.185 ±0.005" (4.70 ±0.13 mm). In the case of stem gaskets, neoprene (with its low degree of hydrogen bonding capacity) is good unless the methylene chloride content of the formula exceeds about 25%. Buna is possibly the best from a weight loss standpoint, but even small additions of methylene chloride can be disastrous. The modified bunas used in Europe and to a small extent in the U.S.A. are very good and have less sensitivity to methylene chloride. Butyl rubbers are generally excellent, but are subject to a $5.00/M upcharge in the U.S.A. Rather surprisingly, the Viton fluorinated polymers are extremely poor, often turning into a mush with significant concentrations of DME. Cup gaskets also present a complex picture. GK-45 neoprene has fair resistance in the absence of methylene chloride, but weight losses increase to three or more times the normal rate when 20% of this solvent is included in formulations. The Precision PE-sleeve gasket is rated as excellent. A bit of weight loss may take place for a day or two, but then the PE seems to cold-flow and seal off any crevices or imperfections, so that further losses become quite low indeed. (This also occurs with other high-solvent formulations.) Cup gaskets of the cut or pre-formed type show varied performance. Neoprenes are acceptable in general, but buna is good only where methylene chloride is absent. European studies have shown that the three common water-based cut gaskets are acceptable, as are some of the new laminated cut gaskets using buna/neoprene at different Durometers for optimum sealing. Viton cut gaskets are totally unacceptable. Weight losses as low as 0.3g/yr have been reported for the combination of butyl stem gaskets and PE-sleeve gaskets under ambient storage using a 50% ethanol and 50% DME formulation. Replacing the PE-sleeve with a GK-45 gasket increased the loss to 0.5 g/yr. In the case of a higher solvent formulation: 10% petroleum distillate, 40% 1,1,1-trichloroethane, 20% methylene chloride and 30% DME, valves with butyl stem gaskets
Aerosol Propellents 357 and eidier PE sleeve, water-based flowed-in or various cut type gaskets gave ambient losses of 2 to 4 g/yr. With GK-45 this increased to 7 g/yr. In fact, die GK-45 gasket will give an unusually wide spread of individual container leakage rates widi many DME formulas. In one sequence of 72 cans rates ranged from 0.4 to 73.4 g/yr. In any event, the above information should be regarded as indicative only. Extensive weight loss studies should always be run, preferably using stem and cup gasket combinations suggested by die valve companies for the formulation type under consideration. The toxicological profile of DME is very good. It has a low order of acute, subacute and subchronic inhalation toxicology. Chronic studies funded by du Pont are now in progress. In one key study, rats were exposed to as high as 20,000 ppm of DME for seven mondis. There was no gross, clinical or histiopadiologic evidence of toxicity, odier dian a 2% decrease in liver weight for rodents exposed at die highest DME level tested. There are no mutagenic or teratogenic effects, at least up to die tested limit of 28,000 ppm. The propellent is metabolized rapidly in die body. It is a very weak cardiac sensitizer. In studies at two laboratories an effect level (EC5o) of about 200,000 ppm (20v%) in air was established. After a review of die toxicological data to date, the Dutch government adopted a provisional no-effect exposure level of up to 10,000 ppm (lv%) for DME. The E.I. duPont de Nemours Co. has established an acceptable exposure limit (AEL) of 1,000 ppm for workers. Until die long-term, two-year inhalation studies are complete die company requires diat dieir DME be used only where inhaled concentrations will Table be very low. They will not offer die propellent for cosmetic and air freshener applications, for example. In Japan, where flammable propellents cannot be used for cosmetics or personal products by order of die Ministry of Healdi, a petition has been filed to allow die use of such propellents, provided die flame extention of die final aerosol product does not exceed 8 " (20 cm). DME is not of concern as a possible depletion agent for stratospheric ozone. The material is attacked rapidly by tropospheric hydroxyl radicals and nitrogen oxides under die influence of ultraviolet radiation. This accounts for about 99.9 + % of DME and an additional 0.02% or so is rained out into die aquatic environment. Somewhere between about 0.10 to 0.01% of die gas is diought to penetrate into die ozone layer some 10 miles (16 km) high, given a sufficient span of years, but even dien no depletion-related reactions are expected to occur from diis off-sourced contaminant. Solubility Aspects of DME The water solubility properties of dimediyl edier are quite unique. They have paved die way for die commercial introduction of certain water-based paints and are being studied for numerous odier applications. In die formulation of polyurediane aerosols, die introduction of very minor amounts of DME acts to tie up traces of moisture that would odierwise affect adversely the long-term stability of die urediane pre-polymer. For example, widiout 2 or 3% DME many formulas will turn very viscous or even harden widiin about 6 to 12 mondis at ambient storage. Widi it, diese same formulations have exhibited up to 30 mondis of good storage in tests conducted to date. (These data relate to aerosol units that have never been actuated. After an XXXIV Solubility and Pressure Development for DME and 25%P-152a/75%DME Mixtures With Water, Ethanol and 50/50 w% Solutions of Ethanol and Water Pressure 64 63 60 50 40 30 20 10 0 DME Water* 0 63 72 79 85 90 94 100 Propellent Ethanol 0 13 41 57 71 82 91 100 50/50 (W:E) _ 0 21 48 63 75 85 93 100 Water* * 0 93 + 93 96 89 98 + 99 99 + 100 25% P-152a/75% DME Ethanol 0 3 10 35 53 66 78 89 100 Propellent 50/50 (W:E) 0 3 10 44 74 84 93 99 100 'Insolubility range: 6 to 34% water. (Blends over 6w% ethanol are miscible.) **Insolubility range: 3 to 92% water. (All compositions over 27w% ethanol are miscible.) Next Page
Aerosol Propellents Previous Page and eidier PE sleeve, water-based flowed-in or various cut type gaskets gave ambient losses of 2 to 4 g/yr. With GK-45 this increased to 7 g/yr. In fact, die GK-45 gasket will give an unusually wide spread of individual container leakage rates widi many DME formulas. In one sequence of 72 cans rates ranged from 0.4 to 73.4 g/yr. In any event, the above information should be regarded as indicative only. Extensive weight loss studies should always be run, preferably using stem and cup gasket combinations suggested by die valve companies for the formulation type under consideration. The toxicological profile of DME is very good. It has a low order of acute, subacute and subchronic inhalation toxicology. Chronic studies funded by du Pont are now in progress. In one key study, rats were exposed to as high as 20,000 ppm of DME for seven mondis. There was no gross, clinical or histiopadiologic evidence of toxicity, odier dian a 2% decrease in liver weight for rodents exposed at die highest DME level tested. There are no mutagenic or teratogenic effects, at least up to die tested limit of 28,000 ppm. The propellent is metabolized rapidly in die body. It is a very weak cardiac sensitizer. In studies at two laboratories an effect level (EC5o) of about 200,000 ppm (20v%) in air was established. After a review of die toxicological data to date, the Dutch government adopted a provisional no-effect exposure level of up to 10,000 ppm (lv%) for DME. The E.I. duPont de Nemours Co. has established an acceptable exposure limit (AEL) of 1,000 ppm for workers. Until die long-term, two-year inhalation studies are complete die company requires that uieir DME be used only where inhaled concentrations will Table 357 be very low. They will not offer die propellent for cosmetic and air freshener applications, for example. In Japan, where flammable propellents cannot be used for cosmetics or personal products by order of die Ministry of Healui, a petition has been filed to allow die use of such propellents, provided die flame extention of die final aerosol product does not exceed 8 " (20 cm). DME is not of concern as a possible depletion agent for stratospheric ozone. The material is attacked rapidly by tropospheric hydroxyl radicals and nitrogen oxides under die influence of ultraviolet radiation. This accounts for about 99.9 + % of DME and an additional 0.02% or so is rained out into die aquatic environment. Somewhere between about 0.10 to 0.01% of die gas is diought to penetrate into die ozone layer some 10 miles (16 km) high, given a sufficient span of years, but even dien no depletion-related reactions are expected to occur from diis off-sourced contaminant. Solubility Aspects of DME The water solubility properties of dimediyl edier are quite unique. They have paved die way for die commercial introduction of certain water-based paints and are being studied for numerous odier applications. In die formulation of polyuremane aerosols, die introduction of very minor amounts of DME acts to tie up traces of moisture that would odierwise affect adversely the long-term stability of die urediane pre-polymer. For example, widiout 2 or 3% DME many formulas will turn very viscous or even harden within about 6 to 12 mondis at ambient storage. Widi it, diese same formulations have exhibited up to 30 mondis of good storage in tests conducted to date. (These data relate to aerosol units that have never been actuated. After an XXXIV Solubility and Pressure Development for DME and 25%P-152a/75%DME Mixtures With Water, Ethanol and 50/50 w% Solutions of Ethanol and Water Pressure 64 63 60 50 40 30 20 10 0 DME Water* 0 63 72 79 85 90 94 100 Propellent Ethanol 0 13 41 57 71 82 91 100 50/50 (W:E) _ 0 21 48 63 75 85 93 100 Water* * 0 93 + 93 96 89 98 + 99 99 + 100 25% P-152a/75% DME Ethanol 0 3 10 35 53 66 78 89 100 Propellent 50/50 (W:E) 0 3 10 44 74 84 93 99 100 'Insolubility range: 6 to 34% water. (Blends over 6w% ethanol are miscible.) **Insolubility range: 3 to 92% water. (All compositions over 27w% ethanol are miscible.)
358 The Aerosol Handbook actuation, effects induced by the non-metallic valve components may cause strong increases in viscosity after 30 to 60 days.) The water-ethanol-DME system is of particular interest. DME is soluble up to 35% in water. If 6% ethanol is added to any ratio of water and DME, complete solubility will occur. DME dissolves in water with the evolution of a fair amount of heat, indicating that strong bonding forces are involved. The physical affinity between the two is so intense that pressure builds up slowly as DME is added. Also, because of this same intra-molecular attraction, the particle size of the spray tends to be coarser than anticipated. By adding ethanol, these properties are diluted and the spray pattern improves. Du Pont has recommended the use of P-152a (CH3CHF2) in conjunction with DME. P-152a contributes the pressure requirement while DME provides solvency and adds to the total percentage of propellent present. Both have about the same pressure and flam- inability levels (similar LELs) and this is a further benefit. The pressure properties of DME in ethanol, water, and ethanol/water (50:50 w%) solutions are compared with those of 25% P-152a/75% DME in the same solvents in Table XXXIV (Page 357). DME is similar to ethanol in that its affinity for water is sufficient to cause a relative contraction in the density of its water solutions, compared with the theoretical densities. This is illustrated in Table XXXV. The strong solvent powers of DME are beneficial in the formulation of cologne and perfume aerosols. Table XXXV Pressure and Density of DME Solutions in Water Temperature = 70°F(21°C) Density DME Content 0% 5% 10% 15% 20% 25% 30% 35%' 40%* 60%* 80%* 100% Ps'g 0 10 19 29 38 48 57 63 63 63 63 63 Pressure kPa 0 67 135 197 264 331 393 434 434 434 434 434 Theoretical g/ml 0.999 0.975 0.953 0.929 0.907 0.889 0.871 0.852 0.833 0.769 0.724 0.668 Actual g/ml 0.999 0.994 0.986 0.976 0.966 0.952 0.935 0.905 0.894 0.820 0.746 0.668 *An immiscible, two-phase solution is formed. Essential oils contain heavy notes or fonds: resinous substantive ingredients that are easily precipitated upon the addition of apolar substances to the concentrate. This has posed problems in the case of hydrocarbon propellents, mostly resolved by using carefully screened perfume bases and a minimum level of propellent. With DME, even at rather high concentrations, the perfume ingredients remain soluble, providing a clean solution and a more balanced fragrance. The DME also helps lift or exalt the perfume notes. It allows the introduction of more water to the formula, if desired. It is also less flammable than the hydrocarbons and provides a lower flame extension plus greater relative safety, if a bottle is ruptured near a flame source. And finally, since it smells rather like ethanol (with which it is isomeric), DME fragrance products are said to have truer odors than those that use other propellents. During 1981 a well known multi-national marketer in Europe successfully launched a line of hydroalcoholic perfume and deo-cologne sprays, all based on DME. Hydroalcoholic and water-based bathroom air freshener sprays containing DME have been sold successfully in several European countries for a decade. The cans are set in a frame attached to a wall surface and are activated with a pull cord or chain. Hydroalcoholic hair sprays containing up to about 15% water, along with 35 % ethanol and 50 % DME, have been developed and show fast drying times, essentially no curl retention problems, and flame projection test results of only 12 " (300 mm), compared with 16" to 20" (400 to 500 mm) for the anhydrous hydrocarbon types. These products are now commercial in Europe. Underlying all these product developments is the element of cost. Both ethanol and isopropanol are taxed and are thus very expensive in Europe. By using a larger amount of propellent (facilitated by DME) costs can be reduced since less alcohol is required. A similar rationale can be made for using more water, which (again) is facilitated by DME formulations. Typical prices in Holland at the beginning of 1981 were as follows: DME: 0.66 Guilder/liter = $1.293/U.S. gallon = $0.232/lb. Ethanol: 8.00 Guilder/liter = $15.50/U.S. gallon = $2.370/lb. Isobutane: 0.50 Guilder/liter = $1.00/U.S. gallon = $0.265/lb.
Aerosol Propellents 359 Table XXXVI Solubility of CO2 and N2O in Selected Solvents Solvent Solubility (w/w% at 100 psig and 70 °F) COj N20 Ethanol(100%) Water Dimethyl Ether (DME) 5.37 1.23 10.38 5.53 0.39 11.39 Bohnen (Aerofako bv) reports the NaO solubility in DME as 19.1 g per 100 ml at 145.5 psig and 68°F(1.00 MPa at 20°C.) Solubility is thus 28.9 g per 100 g of DME. Similarly, he reports the COi solubility in DME as 17.4 g per 100 ml at 145.5 psig and 68°F (1.00 MPa at 20°C.) Solubility is thus 26.4 g per 100 g of DME. Using the tabulated data the N2O and CO2 values in the following formulas can be calculated: Ethanol(100%) Water Dimethyl ether N,0 25.0% 45.6% 25.0% 4.4% Ethanol(100%) Water Dimethyl ether co2 25.0% 45.5% 25.0% 4.5% for 100 psig at 70°F (689 kPa at 21°C) conditions. Actually, the gas concentrations are about 10% lower than shown, probably because some of the binding capacity of the DME is used in attracting the water. at a time when the Guilder was $0,518. One year later the exchange rate had slipped further, to $0,393, presumably making the chemical costs even less expensive in terms of U.S. dollars. The fiscal situation in the U.S.A. is remarkably different. Our ethanol is tax-free and sells for about 10% of the Dutch price, while DME is marketed at $0.57/lb. by the sole U.S. supplier, which is around over two times the estimated current price in Europe. As a result, marketers wishing to use DME must first be prepared to pay more for their product, even if more water is used. This key factor is expected to strongly depress U.S. sales of DME except in those specific circumstances where the use of this unique propellent provides a benefit that outweighs the financial disincentive. One interesting approach for reducing the level of expensive DME (in the U.S.A.) is to add C02 or N20 propellents. Aside from dimethyl sulfoxide (DMSO), DME probably has a higher solvency for these gases than any other liquid or gas liquid. Solubility data are supplied in Table XXXVI. In the examples illustrated, about 4% of either CO2 or N20 can be injected into 25% DMW formulas. Such amounts are capable of significantly reducing particle size, or of allowing the use of more water and less DME while preserving the original particle size. Addition of small, solubilized or floating amounts of propane have been considered for the same purposes. Flammability of DME Formulations DME may be considered as a partly burned form of ethane. Experimentally, it has 63.8% of the caloric content of propane. In the flame projection test pure DME typically produces a 12" (300 mm) flame, whereas pure hydrocarbons typically generate flames of 24" (600 mm). The flame is generally light blue, small and transparent, unless significant amounts of liquid or gas liquid hydrocarbons are included in DME formulations. Some typical results are provided in Table XXXVII. Another aspect of flammability is the volume of flammable vapor-in-air mixture produced by the spray. The volume may be measured in a time frame, or in terms of the weight of product. Since aerosol valves can vary widely in delivery rate, the volume of LEL gas/air mix- Table XXXVII Flame Projection Results with Dimethyl Ether (DME) Formulas (At valve delivery rates of 0.8 g/sec. and a temperature of 70°F (21°C) Composition 9 10 11 12 13 14 Ethanol (100%) Petroleum Distillate Methylene Chloride P-113(CCl2F.CClF2) Water Dimethyl Ether (DME) 50 45 40 35 30 25 35 0 50 5 50 10 50 15 50 20 50 25 50 14 80 — 10 15 20 20 25 — — 15 — — — — 55 — 50 — — — 55 — 35 — 65 55 60 — — 30 25 20 25 20 20 45 Flame Projection (inches) (mm) 12 12 10 8 4 0 0 11 0 300 300 250 200 100 0 0 325 0 0 10 8 14 6 0 250 200 350 150 Flashback (inches) 4300000 0000 000
360 The Aerosol Handbook ture per gram of product has often been taken as a standard of flammability. Experimentally this is measured most often in a closed drum tester of 55 gallon (200 liter) capacity. For gas mixtures with no liquid components it has also been measured using a 4 "i.d. x 32" high (100 mm i.d. x 813 mm high) Lucite tube fitted with a spark plug next to the head of a wooden match. The tube is partly evacuated (typically to 200 mm pressure) and then refilled with the desired partial pressure of test material, plus air back to atmospheric pressure. The tube is inverted several times, allowing three or four loose rubber stoppers to fall through the gas space to facilitate gas mixing, and the ignition source is then actuated to see if the gas mixture is flammable. This device, developed by du Pont, is useful in determining LEL and UEL values. The LEL for DME is 3.4v% in air (86 g/m3), while that of a comparable pressure propane/isobutane blend is about 1.95v% in air (53.6 g/m3). In the closed drum test the comparison is 14.7 g to LEL for DME to only 8.3 g for hydrocarbon A-63. These relationships have significance in circumstances where aerosol products are totally discharged at one time, either during normal use (such as an indoor insect fogger) or by dispenser leakage or rupture. If substantially more product is needed to cause a possible fire, then that product is inherently safer. A final flammability consideration is BTU content. Because DME has only 13,310 BTU/lb (755 K.cal/100 g) compared with a typical figure of 21,350 BTU/lb (1204 K.cal/100 g) for the hydrocarbon propellents, and because DME formulas often contain more water, they are generally much lower in BTU/lb or fuel content value. As an example of this, two typical hair spray formulations can be compared: 67% Ethanol Concentrate 8% Water 25% Propane/isobutane A-36 14,250 BTU/lb (808 K.cal/100 g) 35% Ethanol Concentrate 15% Water 50% Dimethyl Ether (DME) 11,450 BTU/lb (650 K.cal/200 g) The formulations have essentially the same spray characteristics, wetness and other properties, yet the DME type has only 80.3% of the BTU/lb of the hydrocarbon version. This is of interest to warehousemen and fire fighters, since the lower fuel content formula presents less of a potential fire hazard. In summary, dimethyl ether is a highly interesting propellent, capable of doing many things better than the conventional propellents. It is destined for a greater role in European and Japanese aerosol products. If the price decreases in the U.S.A. and Canada, its utilization in those two countries should increase remarkably in the coming years. Methylethyl Ether and Diethyl Ether Methylethyl ether (CH3OC2H5) has a boilingpoint of 45.7°F (7.6°C), a density of 0.697 g/ml at 70°F (21.1°C) and a pressure of 9.8 psig at 70°F (67.6 at 21.1 °C). It is thus far a laboratory curiosity, commonly made by the method of Williamson, from ethyl iodide (C2H5I) and sodium methoxide (CHsONa) in yields of about 81 %. If needed commercially it can be made by the dehydration of methanol and ethanol, although in much lower yield, since dimethyl ether and diethyl ether are large by-products. About 18w% of water can be dissolved in MEE under its own vapor pressure at 70°F (21.1°C). It has a pronounced ethereal odor. If MEE is ever commercialized other propellents will have to be added, since it does not have a vapor pressure sufficient for aerosol uses. Diethyl ether (C2H5OC2H5) has a boiling point of 94.3°F (34.6°C), a density of 0.708 g/ml at 700°F (21.1°C) and an ability to dissolve 7.4w% water at 70°F (21.1°C). It is not a true propellent. DEE is available as a by-product of the preparation of ethanol by hydrating ethylene with sulfuric acid and water. It is also obtained in good yield by the reaction of Senderens: heating ethanol over alumina inoculated with iron (III) chloride, at about 500°F (260°C). The material possesses a very strong typically ether-type odor, recognizable by some people at concentrations below 1 ppm in air. The only commercial aerosol use of DEE is in the preparation of engine starting fluids. A typical formulation might contain 0.5% lubricating oil, 90.0% DEE and 9.5% of carbon dioxide. Since DEE has the fairly unique ability to shrink valve elastomers, making crimp dimensions very critical if leakage is to be avoided, one or two marketers have elected to include very small amounts of methylene chloride in their products to help counteract the shrinkage problem. The odor of DEE can be smelled at the valve of any engine starting fluid aerosol by simply removing the protective metal cap.
Aerosol Propellents 361 Bis(diiluoromethyl) Ether and Bis(trifluoromethyl) Ether During 1977 W.R. Grace began promoting two compounds: the first is variously called bis(difluoro- methyl) ether, sym-tetrafluorodimethyl ether, per- fluorodimethyl ether and finally 6-FDME. They were proposed as non-flammable propellents having good solubility and free from any implication with the stratospheric ozone layer. They are made, rather expensively, by the electrolytic fluorination of dimethyl ether and the company holds several U.S. Patents covering this art. For the price to get under about $2.00/lb. (1982 basis) the fluorination process would have to be done by means of reactions of a regular chemical nature, involving hydrogen fluoride. Preliminary toxicology yielded good results, such as acute toxicity and erythmial tests on the monkey, five and ten day ingestion and irritation studies and a 90 day inhalation test. Results of the Ames mutagenicity test were negative. 4-FDME and 6-FDME exhibit physical properties as shown in Table XXXVII. By adding 10% 6-FDME to 4-FDME the vapor pressure is elevated from 20 psig to 36 psig at 70°F (138 to248kPaat21.1°C), and by adding 25 % of 6-FDME a pressure of 50 psig at 70°F (348 kPa at 21.1 °C) is attained. 4-FDME has a strong affinity for such polar solvents as water and ethanol; a 50% 4-FDME and 50% ethanol (95v%) solution has a pressure of only 5 psig at 70°F (35 kPa at 21.1°C). These propellents dissolve significant amounts of such items as propylene glycol, dibutyl phthalate and sorbitan trioleate. They do not swell diptubes, but may extract the black colorants from exposed buna rubbers r as in glass aerosol valves. In summary, there are no commercial plans for these potentialy useful propellents as yet, largely due to the cost of completing the toxicological profile and the cost of the materials themselves. The Compressed Gases The compressed gas propellents are generally considered to consist of carbon dioxide (CO2), nitrous oxide (N20) and nitrogen (N2). Theoretically the field is much larger and also includes ethane (C2H6), which was described earlier, argon (A), helium (He) and difiuoromethane (CH2F2). However, these latter gases do not have any commercial aerosol applications in the pure form and are therefore not usually discussed. The term ' 'compressed gas'' is denoted by the industry to mean a high pressure propellent that must be injected into containers in the gaseous form instead of as a liquid under pressure. This is in marked contrast to the regulatory definition, as set forth by the Department of Transportation (DOT) and various agencies, and which is supported by the Compressed Gas Association (CGA) and other standard-setting groups. According to the DOT, a compressed gas is, "Any material or mixture of materials having in the container either an absolute pressure exceeding 40 psi at 70°F or an absolute pressure exceeding 104 psi at 130°F, or both, or any liquid flammable material having a Reid (ASME Test D-323) vapor pressure exceeding 40 psi- absolute at 100°F.'' From all this it is possible to have a substance defined as a compressed gas, even if it exerts a pressure as low as about 4 psig at 70°F (27 kPa at 21.1°C), provided it is flammable. The aerosol technologist presently considers that the "liquefied propellents" are those which can be shipped by ordinary tankcar and tanktruck, and thus have pressures equal or less than that of Polymerization Grade propylene; e.g. 156 psig at 70°F (1.076 MPa at 21.1°C). These gas liquids can be added to aerosol dispensers by standard T-t-V or U-t-C gassing techniques. Probably the highest pressure example of such propellents that has been filled to date is a blend of 4w% ethane and 96w% propane with a pressure of 128 psig at 70°F (883 kPa at 21.1°C). At pressures above Table XXXVIII Properties ofSym. Tetrafluorodimethyl Ether and Perfluorodimethyl Ether Property Formula Molecular Weight Vapor Pressure (psig at 70°F) Vapor Pressure (psig at 100°F) Freezing Point - approx. (°F) Boiling Point (°F) (1 atm) Vapor Density at Boiling Point (g/ml) Density of Liquid (70°F) (g/ml) Flammability Sym-Tetrafluoro- Dimethyl Ether (CHF2)20 118 20 54 -240 28.4 0.005304 1.3 None Hydrolysis in 1 % NaOH Solution None (80°F) Perfluoro- Dimethyl Ether (CF3)20 154 217 345 -240 -67 0.011733 1.4 None None
362 The Aerosol Handbook 1200 1100 1000 f 3 900 w p 800 w to W * 700 P. 600 500 400 200 100 I -_. 1 1 i 1 ! ! . 1 i \ I i i i i — -- — — < :1tl iOp -- i bal — lm nts 1 N?( ) — — 0 10 20 30 40 50 60 70 80 90 100 TEMPERATURE (°F) Figure 24. Pressure of C02 and N20 Propellents at Various Temperatures 1.06 1.00 0.95 n -- i i — N K 1 ! i i 1 i 1 — Xk 1 N ! i 1 I ;~1 ■ - ! i — ... — V ^ --* '~i~" 1 ! N i - ~t 1 — .... - 1 i ! Ctl — tlcal Point ' 1 1 ^_ — i 1 1 1 I 0.75 S5 W 0.70 a 0.65 0.60 0.55 0.50 0 10 20 30 40 50 60 70 80 90 100 TEMPERATURE (°F) Figure 25. Density of C02 Propellent at Various Temperatures this, end-buckling of tinplate cans could occur, especially under warm gassing conditions. From all this we can suggest that the "aerosol compressed gas" category embraces gases with pressures higher than about 135 to 155 psig at 70°F (930 to 1068 kPa at 21.1°C), and which must be gassed into containers by gasser-shaker, pre-saturation gassing, T-t-V instantaneous impact gassing (with an appropriate valve design) or U-t-C instantaneous impact gassing methods. The term "fixed gas" or "permanent gas" relates to those gases such as nitrogen, helium and argon that are always gaseous (never liquid) at ambient temperatures. These are older terms, now rarely encountered. The physical properties of several aerosol compressed gases are indicated in Table XXXIX. The compressed gases were the first aerosol propellents, CO2 having been used as early as about 1840 in the pressurization of certain milk products. Since then CO2 and N2O have been used in a number of food products, such as whipped creams, ice cream toppings, fruit flavored concentrates for addition to water or milk, chocolate milk concentrates, salad dressings, meat sauces, simulated butter sprays, popcorn sprays, garlic sprays, squirt-type drink mixes (such as in the home bar compounding of Manhattans of Daiquiris) and even an experimental pancake batter. Outside the food field, CO2 is used often in such diverse products as starting fluids, bug killers, stain repellents for upholstery, disinfectant/deodorants, engine cleaners and windshield de-icers. Since both CO2 and N2O have significant solubility in water, they can be added to foam products to destabilize the foam to various degrees. For instance, if nitrous oxide is added to a standard shave cream, the foam structure at the surface of the puff will "melt" to give an enhanced, pearly appearance. When the gases are added to various hydrocarbon-propelled cleaning products, the stability of the foam layer decreases and it is more readily absorbed into the cleaning cloth, rather than just being pushed around without significantly wetting either the cloth or the surface. The addition of about 50 psi (345 kPa) of nitrous oxide is usually sufficient. Conversely, a chocolate flavored ice cream topping propelled with nitrous oxide displayed surface darkening of the foam structure after a minute or so, and this was quite obvious by contrast when the topping layer was spooned, exposing the lighter product below. By the addition of a water insoluble propellent, such as
Aerosol Propellents 363 Freon FP-C-318 or Freon FP-115, at about 1%, the foam was stabilized and the problem resolved. The foam destabilizing properties displayed by CO2 and N2O can be duplicated and even exceeded by other propellents showing water solubility, as well as by the addition of ethanol, isopropanol, glycol monomethyl ether (methyl cellosolve), silicone antifoams and other specific chemicals according to need. To get to the so- called quick-breaking foam stage a significant amount of co-solubilizing material is usually needed. About 25% of either dimethyl ether or ethanol may be sufficient, especially if a water soluble propellent such as CO2, N2O or P-152a can be included also. The compressed gases have high pressures, actually far beyond the strength of ordinary aerosol cans. The pressure-temperature curves for both CO2 and N20 are shown in Figure 24. The related density-temperature curve for CO2 is shown in Figure 25, and the curve for N20 (not shown) is almost identical to it at ambient temperatures. Because of the high pressure characteristic, solubilities of these gases must be expressed as a function of both pressure and temperature. As the gases are added, the pressure increases linearly with concentration, starting with that of the original contents as a baseline. This concept is quite accurate to about 200 psig (1.380 MPa), and thus covers all aerosol applications. Up to 200 psig (1.380 MPa) of CO2 and N2O have been added to a number of pure substances and several solutions without causing phase separations. The miscible status of barely miscible solutions might be altered by additions of these gases, but this has not been tested. In some cases considerable heating accompanies the introduction of CO2 (and to a lesser extent N2O) into certain solvents, such as ethanol and acetone. At least some heating (the Joules Effect) occurs for almost every solvent tested. Except in the case of water, where CO2 reacts to form carbonic acid, the usual compressed gases do not combine chemically with aerosol ingredients. The solubility relationships of CO2, N2O, N2 and other gases have been described classically using such concepts as the Ostwalt Solubility Coefficient, mol% solubility per atmosphere of partial pressure and so forth. In order to convert between the OSC (X) and the weight of gas filled into an aerosol container under a set Table XXXIX Physical Properties of Certain Compressed Gas Propellents Property Formula Molecular Weight Vapor Pressure (psig 70°F) Freezing Point (°F) Boiling Point (°F) Specific Gravity (liq.) (70°F) Specific Gravity (gas) (70°F) Air = 1 Density (gas) g/1 32°F 760 mm Density (solid) (-109.2°F) Critical Temperature (°F) Critical Pressure (psig) Critical Density (g/ml) Flash Point (°F) Explosive Limits in Air Solubility in Water (ml/100 ml water at 32°F) Solubility in Water (ml/100 ml water at 70°F Carbon Dioxide CO2 44.0 830. -69.9* -109.2" 0.721 1.530 1.9768 1.561 87.80 1056. 0.468 none none 179.7 85.4 Nitrous Oxide N2O 44.0 745. -131.5 -127.26 0.720 1.530 1.977 97.7 1052. 0.457 none none 130.52 69.62 Nitrogen N2 28.0 na -345.93 -320.44 na 0.971 1.258 -232.6 491.5 0.311 none none 2.35 1.51 Helium He 4.0 na -456.1 -452.0 na 0.138 1.176 -450.2 33.2 0.0693 none none 0.97 1.02 Argon A 39.9 na -326.6 -302.6 na 1.383 1.793 -187.6 704.2 0.531 none none 5.60 3.0 ♦At 76.3 psig (526 kPa). **Sublimes.
364 The Aerosol Handbook of experimental conditions we can use the equation of Hsu: XX = (WRT/VCMP) + (X-l), where: X = Ostwald solubility coefficient (OSC) X = Volume of liquid divided by volume of the container W = Weight of compressed gas added (g) R = Gas constant (82.06 ml-atm/mole-°K) T = Temperature (°F) Vc = Volume of container (ml) M = Molecular weight of compressed gas P = Total pressure (atmospheres, absolute) Such concepts seem bulky and academic to the aerosol chemist, and they pose some rather lengthy translational difficulties for those who must consider solubilities in the more pragmatic framework of grams per can. In formulation work, a result based on theory would be checked experimentally in any event, to avoid possible errors or inaccuracies. A more practical guide has been developed, using air-free 202 x509 aerosol cans (287 ml) filled to 80v% of capacity (230 ml) with various pure solvents or propellents. The weight of CO2 or N20 required to produce a pressure of 100 psig at 70°F (690 kPa at 21.1°C) was then determined. It was recognized that the 20v% head space would contain a portion of the gas; actually 0.0139 g/ml, or 0.792 g/can, and that this could be a very important percentage of the total gas weight if the solvent or propellent could dissolve only a small percentage. The data provided in Table XL shows the results of this study. To be more exact, as gas is added the liquid volume swells, by about 1.3 ml per gram of CO2 or N2O, and Table XL Solubility of CO2 and N20 in Certain Aerosol Liquids and Propellents Solvent Isobutane n-Butane Odorless Min. Spirits Water Ethanol (100%) Isopropanol (99.5%) Acetone Dimethyl Ether Methylene Chloride 1,1,1 -Trichloroethane P-ll (CChF) Gas N2O co2 N20 co2 N20 cc-2 N20 C02 N20 C02 N20 C02 N20 C02 N2o C02 N20 C02 N20 C02 N20 C02 Solvent Weight Per Can (g) 128.1 129.3 133.5 133.5 170.5 170.5 229.2 229.7 177.7 177.6 176.4 177.2 180.1 179.1 151.9 151.7 301.0 300.5 296.4 296.5 357.4 355.8 Gas Wt. To Reach 100 psig at 70 °F (g) 10.17 7.25 11.26 7.81 9.76 6.27 1.68 3.50 10.80 10.48 9.46 7.95 20.31 24.06 19.65 17.75 20.25 16.92 16.90 13.35 18.50 13.00 Gas Wt. Required to Reach 100 psig at 70 °F (w/w%) (g/100ml)* (g/100ml)'* 7.33 5.31 7.78 5.52 5.41 3.46 0.729 1.500 5.73 5.57 5.10 4.30 10.13 12.08 11.48 10.46 6.31 5.34 5.40 4.32 4.92 3.53 4.42 3.16 4.90 3.40 4.25 2.73 0.733 1.524 4.70 4.56 4.11 3.46 8.83 10.45 8.54 7.72 8.80 7.37 7.35 5.80 8.05 5.65 3.98 2.82 4.44 3.04 3.71 2.36 0.392 1.224 4.32 4.18 3.59 3.19 7.91 9.22 7.65 7.03 7.87 6.73 6.71 5.40 7.21 5.26 70 °F 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 Pressure (psig) 100 °F 143.5 141.0 141.0 134.5 125.5 122.0 135.0 140.0 136.0 136.0 124.5 122.0 133 143 136 135 131.0 132.5 136.0 135.5 130°F I — 151.5 142.0 174.0 182.0 175.0 172.5 152.0 146.0 179.5 176.0 *Of solvent; e.g. gas weight divided by 2.30. (Discounts head space gas.) "Of solution. Excludes head space gas, figured at 0.000139 g/ml/psig of N20 or COa paitial pressure, at 70°F.
Aerosol Propellents 365 this makes the head space smaller. In the case of avid solvents, such as acetone and dimethyl ether, there is a contractive effect due to intermolecular forces and the volume growth then diminishes to only about 1.0 to 1.1 ml per gram of dissolved gas. A quick survey of Table XL would suggest that acetone is the strongest solvent listed. But it must be remembered that in the case of dimethyl ether, the gas pressure is built upon a base of 63 psig at 70°F (434 kPa at 21.1°C), and that by the time sufficient CO2 or N20 is added to reach 100 psig (689 kPa) the amount dissolved is already 76 to 97 % as great as in acetone, resp. The spray pattern reflects the level of CO2 or N2O in the formula. A volatile solvent also contributes to a finely particled spray. For instance, a 12% solution of CO2 in acetone sprays like a dry gas, and a solution of 6.0% CO2 in equal parts of acetone, methylene chloride and odorless mineral spirits (OMS) gives a very fine spray, like an anhydrous air freshener. A 5% solution of CO2 in anhydrous ethanol gives a spray considererd marginally too wet for hair spray use. However, 6.4% solutions are considered satisfactory, although pressures are too high for tinplate cans. The addition of volatile solvents, such as methylene chloride (up to 20 %) or isopentane (to 15 %) act to bring the particle size of 5% CO2 hair sprays into a good range. A 4.0% solution of either N20 or CO2 in vegetable oil (usually with traces of carotene dye and butter flavoring) makes a very coarse spray suitable for spraying popcorn and even bread slices in institutional kitchens. A similarly coarse spray is obtained with 3.0% CO2 and various odorless or low-odor petroleum distillates, for such products as bug killers and engine degreasers. Finally, there are sprays so low in gas that the only break-up is afforded by using a mechanical break-up valve. They include a commercial line of pet sprays, where the concentrate is about 95% water and where only 0.39% of dissolved N20 is the sole propellent. These sprays are soundless, or almost so, and as such they do not startle pets when actuated. A major concern with CO2 and N20 products involves the inevitable pressure drop during use, as propellent escapes from the liquid phase to enter the enlarging head space. For example, a product very high in ethanol and containing 5% CO2 starts out at a typical pressure of about 90 psig at 70°F (621 kPa at 21.1°C), and during use this pressure dwindles to about 49 psig (338 kPa). due to frictional factors, the delivery rate only drops by about 25 to 30% during this time, and this goes unnoticed by the consumer. In general, the pressure drop aspect has been over-emphasized, along with the concomitant factors of slower delivery rate and a coarsening of the spray. In development, aerosols made at the low end of the pressure specification should be tested for spray acceptability by spraying down to emptiness. Also, vapor valves should never be used, and special care should be taken to assure crimp reliability. Crimp leakage has been more of a problem with CO2 and N20 formulas than others (especially ethanol types). This is due to the high pressures in the can and the fact that these gases are very small molecules, and thus are better able to wriggle through elastomeric seals than the much larger hydrocarbons and fluorocarbons. Only a few grams of propellent loss can have a significant effect upon the product quality. Cans containing both methylene chloride and CO2 and held in upright storage have been checked for both pressure and weight loss after a year, with the finding that over half the weight loss consisted of methylene chloride. Similar results were obtained with 1,1,1-trichloroethane, although loss rates were only 10 to 20% of the methylene chloride packs. Nitrogen gas has been used to pressurize concentrates to be delivered as streams or as very coarse sprays produced by a mechanical break-up valve. One interesting use is the wasp and hornet spray. The concentrate is predominantly a C10H22 type deodorized kerosene, pressurized with about 0.3% N2 to 100 psig at 70°F (689 kPa at 21.1°C). With the proper valve a stream can be projected up to about 16 to 20 ft (4.9 to 6.1 m), which provides a better range and enhances operator safety, although attacking wasps sometimes fly back along the stream to sting the user. When such products are formulated using CO2, sufficient break-up occurs that they are virtually unusable beyond about 6 or 7 ft (2 m). Nitrogen has been used to pressurize toothpaste in non-compartmented aerosol units, probably now obsolete, although on the market for up to about ten years. When used to pressurize food items such as honey or pancake syrups, the product can be dispensed looking like it usually does, but after a second or two it undergoes a metamorphosis, turning translucent, then milky as the nitrogen forms ever larger gas bubbles in the liquid matrix. Eventually, in perhaps ten or twenty seconds, the gas rises to the surface and escapes, leaving a normal product. This would probably be "too much magic" for the consumer, and such products have never entered the market except in very small numbers.
366 The Aerosol Handbook Toxicological Considerations; C02 and N20. The toxicology of CO2 is well defined. It is present in normal air at about 300 ppm, so it is obviously compatible with life forms. CO2 functions as a regulator of the breathing function, and an increase will accelerate the rate of breathing. At 0.1 to 1.0% levels there is a slight but unnoticable increase, while at 2% there is a 50% increase, and at 3% a 100% increase. At 5% the increase rises to 300% and breathing becomes laborious. A level of 10% CO2 can be endured for only a few minutes. From 12 to 15% soon causes unconsciousness and 25% will cause death in several hours. The thresh- hold limit has been established at 5000 ppm (0.5%). The gas has a pungent odor, sharp and acidic, but not unpleasant. The solid form (dry ice) can cause severe frostbite. The toxicology of nitrous oxide has been studied exhaustively. It is well recognized as a medical and dental anesthetic, the so-called "laughing gas" being a mixture of about 80% N20 and 20% O2. Various studies suggest that chronic exposure can cause a number of effects, particularly on frequently dividing cells. They are time and dose dependent. They impair vitamin B12 metabolism and the production of tetra- hydrofolate, which can affect DNA synthesis. Symptoms of sub-chronic exposure include early sensory complaints, loss of balance, leg weakness, gait ataxia, impotence and sphincter disturbances. Changes have been seen in lysosomal lung cells in mice, and damage has been found in the cortical cells of rats. Epidemiologic work has uncovered higher risks of spontaneous miscarriage, liver disease and other serious health problems. A number of deaths have resulted from deliberate deep inhalation, a drug abuse form designed to provide a psychedelic experience but also leading to intoxication, autolethal acts and often simple asphyxiation. Exposure of pregnant rats to N20 showed it to be fetotoxic and a teratogen. The mechanism was not related to the intrinsic mechanism for anesthesia. Xenon gas, a very similar anesthetic, was without effect on the rats. While these toxicological findings may seem a bit grim, and might be sufficient to cause the cancellation of development work on some new propellent, the controlling factor is that about 600,000 clinical and hospital personnel and over 100,000 dental personnel work with the gas during many days each year and yet have suffered no ill-effects. N20 exposures at aerosol filling plants should be far less, and the consuming public would have virtually no exposure at all. It is fortunate that the epidemiological 100 year history of safe use far outweighs the concerns relating to the effects of high- level repeated exposures. Nitrogen (and helium and argon) propellents are probably used in fewer than 1 to 2 million aerosol units per year in the U.S.A., and they are formulated at very low levels, generally in the range of 0.1 to 0.5% of the product. There are no toxicological constraints other than the obvious but remote possibility of asphyxiation in a grossly misengineered and mismanaged production setting. Production Aspects of C02, N20 and N2 Gases CO2 is available as the liquefied gas in either 60 lb (27.2 kg) net cylinders or in tankwagons of varying capacities. The Commercial Grade product contains 99.5%min. CO2, plus 0.342%max. N2, 0.086%max. O2 and 0.072%max. H2O. Although "bone dry" grades and even purities of up to 99.995 % CO2 are also available at a price, virtually all fillers use the Commercial Grade product. Banks of interconnected cylinders can be purchased for smaller operations, but otherwise the so-called "CO2" receptacle" is recommended. It consists of an insulated horizontal bulk tank bolted to a frame that also carries a refrigeration and heating system. Between the two, the propellent is maintained at 2 ± 4°F (-16,7 ±7.2°C) and this keeps the CO2 pressure at 300 ±20 psig (2.069 ±0.140 MPa). Between productions the refrigeration unit operates periodically to keep the liquid sufficiently chilled. During productions, as gas is withdrawn from the top area of the tank a cooling of the liquid phase takes place due to evaporative replacement. When the pressure drops to the base of the established range, a relay turns the heating system on to restore the mid-point temperature. For cylinder banks evaporative cooling can be more of a problem. If nothing is done to rewarm them the liquid CO2 will drop to about -40°F (-40°C) and there will then be insufficient pressure generation to continue the production function. Also, the cylinders will quickly develop a thick coating of ice. To prevent all this, a person should frequently spray the banks with warm water from a hose. Nitrous oxide can be purchased in up to a 99.99% ultra high purity grade, and also in a 99.93% medical grade, but the Chemically Pure Grade at 99.0%min.
Aerosol Propellents 367 N20 is almost always sufficient. The main impurity is nitrogen. N2O is normally made by the thermal decomposition of ammonium nitrate (NH4NO3). Any entrained powder and traces of reactive nitrogen oxides are removed by dissolution in water, after which the purified gas is dried and stored. N2O may be used out of the same type cylinders (60 lbs net, or 27.2 kg) and the same receptacles as were described above for CO2. All conditions and comments apply equally to N2O operations. Unlike CO2, nitrous oxide is a strongly endothermic gas. Heat is absorbed when it is theoretically formed from the elements. The standard heat of formation (AHf°) is 19.49 kg-cal/mol. Although it is essentially unreactive at ambient temperatures, it becomes increasingly active when heated. At above about 450°F (232°C) it functions as a strong oxidant. Recognizing this, any frictional or other heating should be stringently avoided if there is any chance that combustible material may be present, such as lubricating oils or greases. In one memorable occasion a 3/4-inch (19 mm) i.d. steel pipe, carrying 300 psig (2.07 MPa) N20 from a receptacle to a gasser-shaker machine suddenly became red hot at the midsection, just below the ceiling of the gas house. Within another 15 seconds or so it became white hot and then melted, with the released gas jet blowing molten globules of steel in all directions. In another instance, a solution of N2O in methanol (CH3OH) at about 200 psig (1.38 MPa) pressure caused a relatively small pre-saturation tank to detonate in the premises of a Chicago area filler, causing severe consequences. And finally, N2O managed to slowly decompose to N2 and O2 when packed in aerosols with a relatively acidic food condiment, causing cans to explode several months after filling. The product, called "Sizzle Spray", was abruptly discontinued. These three episodes, along with many others, have never been satisfactorily explained. It is known that N2O decompositions are very sensitive to catalysis, and that once initiated on a micro scale they might produce a hot spot that might rapidly enlarge. Catalytic actions might be the key to these mysterious ocurrences. During the early days of the aerosol industry CO2, N2O and their mixtures were injected into sealed cans backwards through the valve, using in-line gasser- shaker equipment, such as the LeMay Machine Co. 's 8 to 11 station machines. The rate of gas addition was a function of the smallest orifice size in the valve, the pressure differential between inlet line and can, the viscosity of the product, the fill volume and the selection of gas. For instance, N2O usually dissolves more slowly than CO2, and with less heat of solution. The shaking efficiency depended, in part, upon the relative size of the head space. If the head space was less than about 16v% (or even 20v% for less fluid products) the gassing time was lengthened because the liquid could no longer be agitated so violently. As of this writing, gasser- shakers are still used widely. They extend from the small, semi-automatic types such as that made by L'Air Liquide, S.A. of France, rated at 8 to 16 cpm, to the advanced 6, 12 and even 18-head rotary types, such as those offered by Andora Automation, Inc., which are capable of speeds up to 160 cpm, depending upon conditions. During the late 1950s in the U.S.A. Kartridg Pak, Inc. developed a pre-saturation method for adding these gases. Considering a typical bug killer for example, consisting of 2 % toxicants, 95% petroleum distillate and 3% CO2, a pre-mix of about 47 parts petroleum distillate and 3 parts CO2 was prepared in a pressure-resistant, baffled, mixing vessel of about 20 to 60 gallon (75 to 227 liter) capacity. The petroleum distillate was maintained at a volume level, and the CO2 was added using a supply line fitted with a pressure regulator which, in this case would be set at about 185 psig (1.276 MPa). After filling the can with 2 parts toxicants and 48 parts petroleum distillate, an equal weight of the pre-mix would be added, using T-t- V or U-t-C propellent gassing techniques. The final can pressure would be about 88 to 90 psig (607 to 621 kPa). The small apparent loss of pressure would actually relate to the fact that the pre-mix was only about 98% saturated, and would also provide gas for the head space of the aerosol can. A schematic diagram is shown in Figure 26 (Page 368). The final injection method, known as instantaneous impact gassing, is undoubtedly the best procedure available, provided the concentrate is reasonably fluid; e.g. about twice as fluid as corn oil. The gas is brought to either the T-t-V or U-t-V gasser under a pressure of typically 625 psig (4.31 MPa) and a fixed volume is rammed into the can at great speed. Before the pressure in the can is able to rise to critical values, the liquid is blasted into a fine mist so that it can absorb the injected gas almost completely. If the process is conducted correctly, the excess pressure (that amount over the equilibrium pressure) will only be about 10 psi (69
368 The Aerosol Handbook kPa), and it will subside completely in a day or two. A term called Impact Gassing Efficiency relates to this pressure difference: % IGE = Equilibrium Pressure x iQ0% Actual Pressure The contents temperature must be the same when measuring both pressures. As a part of the procedure for Actual Pressure determination the can temperature should be measured using a thermistor probe of the "skin temperature" profile. Because of the Joules Effect, measuring the concentrate temperature prior to gas injection will give low temperature results. If the %IGE is below about 80%, the system should be examined. The head space may be too small for adequate agitation. The valve cup wall (in U-t-C operations) may overly concentrate the ram-jet effect of the entering gas, causing different degrees of concentrate break-up. The material may be too viscous, the valve (in T-t-V operations) may not allow ultra-quick entry of the gas into the can, the pressure may be too low, or various settings on the U-t-C may be incorrect. When 7K 5> '&9 <J r-Q* ^ © 1. Product to be packaged in aerosol form. (In this scheme 100% is pre-pressurized.) 2. Transfer pump. 3. Saturator. 4. Compressed gas supply. 5. Pressure regulator. 6. Pressure gauge. 7. Excess pressure pump. 8. Metering pump, or gasser. 9. Aerosol container. Figure 26. Pre-Saturation Equipment for the Addition of C02 and N20 to Aerosols everything is functioning smoothly, rates as high as 288 cpm have been obtained using a re-engineered Kar- tridg Pak 9-head U-t-C gasser with cans as large as the 211 x 713 size. Methylene Chloride With a boiling point of 103.55°F (39.75°C) methylene chloride is not a true propellent, but functions more as a propellent adjuvant or extender. The 1981 production of 545 million pounds (247,000 metric tons) in the U.S.A. was expected to drop to 530 million pounds (240,000 metric tons) in 1982. The major end uses consist of paint removers (30%), aerosol propellents (20%) and degreasers (10%), and this 106 million pound (48,000 metric ton) aerosol propellent market is expected to remain about flat to very slightly upward in the next few years. The price of methylene chloride (inhibited) was listed at $0.305/lb ($0.673kg) at the beginning of 1982, but with a domestic capacity of up to about 825 million pounds (375,000 metric tons) there is great downward pressure on pricing. Imports were 60 million pounds (27,000 metric tons) in 1981, causing still further price problems. Other properties of methylene chloride include, M.W. = 84.94, Freezing Point = -139°F (-95°C), density = 1.3255 g/ml at 20/4°C and water solubility = 2.0% at 70°F(21.1°C). Because of early concerns expressed by the Food and Drug Administration (FDA), the toxicology of methylene chloride has been examined exhaustively. To repeat the total of this work, using 1982 prices, would cost in excess of $20,000,000. The industry position is that methylene chloride should pose no significant hazard to health or the environment when used within established guidelines, according to all animal and human toxicology data now available. Perhaps the key element in the entire battery of about two dozen programs is the massive study, cosponsored by Diamond Shamrock, Dow Chemical Co., Imperial Chemical Industry (U.K.), Stauffer Chemical Co., and Vulcan Materials. The study, conducted by Dow Chemical Co., involves a two-year inhalation of methylene chloride vapors at concentrations of 500, 1500 and 3500 ppm in air by hamsters and rats of both sexes. The test results are based on examination of 90,000 tissue samples taken from 1,896 animals. The final compilation of results shows no increase in malignant tumors in the hamsters and female rats, and only a slight in-
Aerosol Propellents 369 crease in the male rats at the highest solvent level tested. This last finding does not indicate significant risk of cancer or ouier known adverse heakh effects when memylene chloride is used according to accepted exposure guidelines. The LD15 orally in rats is 1.6 ml per kg. It is a narcotic to humans in high concentrations. Methylene chloride is used in aerosol formulations, generally at levels of below about 25%, although levels to 35 % are known in some coating products. An insecticide made in Holland is known to contain about 72%. At above 20% or so, some rather difficult containment problems may occur, simply because methylene chloride is such a strong solvent and can easily cause swelling and penetration of elastomeric seals. Buna gaskets have the lowest resistance, and neoprene types should be used at over about 20%. Considering the aspects of solubility parameter (See Table XXIII) and so forth, neoprene should be affected almost as drastically as buna gaskets. But neoprene is such a dense, tough material that it resists deformation and consequent permeation. Neoprene stem and mounting cup gaskets should be used for products having more than about 20 to 25% methylene chloride. Although weight losses are often five to ten times higher than for non methylene chloride formulas they successfully hold compositions containing as high as 80% of the solvent, provided storage temperatures do not exceed about 104°F (40°C) and a good, tight crimp is applied. Dimensions of about 1.075" crimp diameter and 0.175" crimp depth are recommended. The best valve seal for methylene chloride is Viton, but me very high expense tends to limit its use. Valves with Viton stem gaskets and neoprene-based flowed-in gaskets have been successful with insecticide and paint stripper formulas containing as high as 70 to 80% methylene chloride, even at temperatures to 120°F (49°C), although occasional gross leakers may be encountered, even under ideal crimping conditions. Even better performance can be obtained where bom me stem and cup gasket are composed of Viton. However, Viton cut gaskets for valve cups are so costly that mis ultimate approach is almost never used in practice. Weight loss data for a high methylene chloride insecticide formula are given in die chapter on Crimping. The use of methylene chloride in cosmetic products has been banned in some countries, and limited to 35% or other percentages in odiers. In die U.S.A. and Canada there are no limitations, nor are any being considered. Hair sprays constitute the largest cosmetic product containing methylene chloride, with the solvent incorporated into quite a large number of formulas, generally in the range of 12 to 24%. Consumers start to pick up the solvent odor and skin tingling effects at over about 16%, but they do not develop any purchasing resistance until solvent levels over 20% are used. Many hypo-allergenic persons cannot use memylene chloride hair sprays without developing edema, rash or ouier irritations of the scalp and adjacent skin surfaces. For the manufacturer, memylene chloride facilitates the production of hair sprays by speeding the dissolution of several important film-forming resins mat are sold in solid form. However, it does cost somewhat more than the formula block of about nine parts ethanol and one part A-31 to A-40 which it replaces. It also has a higher evaporative loss rate. Production losses of between 6 to 9% are commonplace, and they get even higher if the methylene chloride is purchased in 600 lb (275 kg) steel drums. Figure 27. Effect of Methylene Chloride on the Cloud Point of Aerosol Hair Sprays (2.00% Resin 80% neutralized with AMP*, in ethanol and with 20. 00% A-4C) « P Jh 20 < s W H 0 — 1 — |S -- t — — i iS i ■^ i s! ~1 ^\7 _S j - — — i i " i Js n! ! — -- ! I ! 1 1 TLj " L iSi — - — - _.._ "t" T" ! r\ i >J i . i i 1 11 -j 1 >v ^slNl - x. ' 'Sl \ I !^L — .._ — - . 1.. rSJ I T\| Sj_±j__llj> ! >< : ; ! -(1.7 H < ■12.2 W P. 3 w -17.8 H -23.4 5 10 15 20 METHYLENE CHLORIDE (',; ) (National S&C Corp.) (National S&C Corp.) (National S&C Corp.) (National S&C Corp.) (GAF Corporation) * This polyiner requires less neutralization; it is 9% neutralized with AMP. Note: Clear points are about 11°F (6°C) higher than cloud points. A = Resyn 28-1310 B = Luviskol VA-28 C - Luviskol VA-37 D ■= Resyn 28-2930 E = Gantrez ES-225*
370 The Aerosol Handbook During product development, methylene chloride provides the formulator with additional latitudes. An important consideration in hair spray formulations is the cloud point: that temperature below which the resin falls out of solution as a white cloud. Usually it goes back to solution when the temperature is raised to about 10°F (6°C) above the cloud point, but the process may be a slow one. Cloud points below 30°F (-1°C) are generally considered acceptable, those between 30 to 40°F (-1 to 4°C) are somewhat worrisome, and those over 40°F (4°C) are definitely unacceptable, since they will result in consumers encountering clogged valves, erratic sprays and white flecks on their hair in some cases, with practically no holding power. Methylene chloride (and also water) acts to depress substantially the cloud point of resins in ethanol/hydrocarbon and ethanol/C02 solutions. Because of this they permit the use of higher percentages of hydrocarbon propellent (a cost saving measure), the use of less compatible resins (such as Resyn* 28-1310 and Luviskol* VA-28), a greater variety of neutralizing agents and (if desired) larger degrees of neutralization than would be otherwise possible. Figure 27 serves to illustrate the effect of methylene chloride as a cloud point suppressant in the case of several hair spray resins. In a similar fashion Table XLI shows the percentages of methylene chloride, and also water, needed to bring several hair spray formulations down to a cloud point of 0°F(-18°C). Salon tests have shown that the addition of up to at least 8 % water or 16 % methylene chloride to hair spray formulas has no negative effect so far as consumers are concerned. This is true even in the so-called "unscented" formulas, where the chemical odor of methylene chloride shows through the very light, nondescript perfumes that are used routinely. On the negative side, the solvent action is sometimes strong enough to loosen hair dyes, dull the plastic frames of eyeglasses, cause skin irritations, and bring about long term degradation of the stem gasket in the aerosol valve, so that the button may tend to stick in the down or actuating position. The solvent has both failed and passed the Ames Mutageniety (screening) Test, and because of the failure, some salesmen selling brands that are free of methylene chloride will rather unscrupulously show buyers copies of various documents, including one in the Federal Register, which cite the Ames test failure and the subsequent concerns of the FDA at that time. This has been a marketing problem to some Table XLI Effect of Methylene Chloride as a Cloud Point Suppressant in Hydrocarbon Type Hair Sprays Formulations with cloud points of 0°F (-18°C). 2.0% Resyn* 28-1310 and 0.18% AMP neutralizer: Propellent A-40 Ethanol Concentrate Methylene Chloride 7.5 92.5 0.0 10.0 84.0 6.0 15.0 71.0 13.5 20.0 61.5 18.5 25.0 51.0 24.0 30.0 41.0 29.0 35.0 30.0 35.0 2.0% Resyn* 28-2930 and 0.18% AMP neutralizer: Propellent A-40 Ethanol Concentrate Methylene Chloride 18.0 82.0 0.0 20.0 78.5 1.5 25.0 70.7 4.3 30.0 62.0 8.0 35.0 52.5 12.5 2.0% Gantrez** ES-225, 9% stoichiometrically neutralized with AMP: Propellent A-40 Ethanol Concentrate Methylene Chloride 20.0 80.0 0.0 25.0 72.0 3.0 30.0 64.0 6.0 35.0 54.5 10.5 2.0% Resyn* 28-1310 and 0.18% AMP neutralizer: Propellent A-40 Ethanol Concentrate Water 7.5 92.5 0.0 For Comparison 10.0 88.7 1.3 15.0 81.2 3.8 20.0 74.6 5.4 25.0 67.7 7.3 30.0 insol. insol. 35.0 insol. insol. 'Registered trademark of the National Starch and Chemical Corp. •Registered trademark of the GAF Corp. 2% solids, or 4% as supplied in 50% ethanol solution form.
Aerosol Propellents 371 extent, for those firms selling hair sprays that contain methylene chloride. Space does not permit any further in-depth product descriptions of formulas that include methylene chloride, but in summary, this solvent is very important to the industry, its safety has been fully established when it is used under reasonable conditions. It is valuable as a strong solvent, flammability suppressant, pressure depressant and viscosity thinner. The outlook for future growth in aerosol applications suggests a marginally upward trend. Specialty Gases that Function as Propellents There are a number of products that contain propellent-type substances where the fact that they are the pressurizing agent is incidental to the central use. Rather common examples include the use of P-12 (CCI2F2) in 100% form as refrigerant refills, boat horn energizers, and for fire extinguishers, personal hazard alarm whistles, cocktail glass chillers (now obsolete) and as a dry, inert purging gas in laboratory settings. Similarly, butanes are used as lighter fluids and propane is used as a fuel source for home and industrial paint stripping and welding. Less routine applications include the use of 100% methyl bromide as a fumigant, particularly for flour and grain products. It is useful for the disinfection and disinsection of commodities on a smaller scale as well. The gas liquid is highly irritating and toxic. It must be handled and filled using extravagent precautions to protect plant personnel. Since it has a boiling point of 38.3°F (3.5°C) and a pressure of 12.9 psig at 70°F (89 kPa at 21.1°C) it is easily handled. The density is 1.732 g/ml at 32 °F (0°C). The usual procedure is to strongly refrigerate the material, then pour it into two-piece aerosol cans of a nominal 12-ounce size (actual 368 ml capacity) and crimp the unit with a threaded valve cup. The density allows the can to easily accommodate 1 lb (453.6 g) fills. In order to use the container, a special valve is screwed onto the cap. It carries a needle-like piercing pin that can puncture the cap, and then, upon withdrawal, allow the gas (or liquid, if the can is inverted) to flow out of the can and through a flexible hose connection to the point of use. Since the gas is toxic and also weakly flammable, precautions must be observed during use, similar to those for filling. In the U.S.A. pre-marketing requirements include product registration with the EPA. The filling of sulfur dioxide [sulfur (IV) oxide; SO2] into aerosol type cans has taken place in the past but may now be obsolete, at least in the U.S.A. The gas liquid has been used as both a refrigerant and fumigant. It has a boiling point of 14.0°F (-10°C) and a vapor pressure of about 60 psig (250 kPa) at 70°F (21.1°C). It is pungent, poisonous and non-flammable. The usual packaging process is the same as described above for methyl bromide. The final example of an aerosol dispensed specialty gas is ethylene oxide (C2H4O). In the pure form it is a very low pressure gas, with a boiling point of 51.3°F (10.7°C). It is extremely irritating and toxic, as well as flammable. The density is 0.887 g/ml at 45.0°F (7°C). Ethylene oxide is used principally as a gas sterilant, but the sterilizer equipment must be explosion-proof and maintained in special rooms with ventilation, blowout sections and other precautionary features. A more acceptable procedure is to use a non-flammable mixture of either 12% EtO and 88% P-12, or 10% EtO and 90% CO2. The first of these compositions is conveniently blended and packaged into aerosol cans by Ben venue Laboratories (Ohio) and a few other fillers. The usual product consists of a 1 lb (453.6 g) fill in a two-piece aerosol can of 357 ml capacity. The pressure is about 66 psig (455 kPa). These containers may be connected to non explosion-proof sterilizing cabinets in ordinary treatment rooms. In practice, a moderate to deep vacuum draw is made on the cabinet enclosure, after which the ethylene oxide mixture is introduced to a pre-set sub-atmospheric pressure. Steam may be pulsed into the chamber during or after the evacuation stage in order to get the relative humidity up to at least 30 % and preferably 50 % to produce spore hydration so that the EtO cidal activity is accelerated. It also helps warm the chamber to the final sterilizing temperature, which is usually somewhat higher than ambient in order to speed up the first-order sterilizing action. The effects of vacuuming, repressurization and temperature must be carefully evaluated if packaged products are being sterilized, for they could be distorted, lose their sealing integrity and fail in their end-use performance. The FDA has been concerned about the local and systemic toxic effects of EtO and its reaction products, ethylene chlorohydrin (ETCH) and ethylene glycol (ETG), as well as reports of the mutagenic effects of EtO and ETCH. As a result, in 1978 they established a "Daily Dose Limit" on drugs amounting to 30 g/kg/-
372 The Aerosol Handbook day for 30 days in the case of EtO, as well as an identical level for ETCH and a limit of 1 mg/kg/day for 30 days for ETC In addition, they will generally defend no EtO sterilization use on foods or cosmetics. On the other hand, cans and bottles can be sterilized, and one firm reliably supplying such a service (for aerosolized drugs and other products) is the Microbiotrol Division of Griffith Laboratories, Inc. in Alsip, IL. The aerosol filling of EtO/P-12 products represents only a micro-segment of the aerosol industry, with a volume of only several million units per year. Nevertheless, it stands as an interesting innovation enlarging the scope of beneficial aerosol products into new areas.
AEROSOL PRODUCTION EQUIPMENT 373 11 The establishment of a major aerosol filling and packaging facility can be an enormously complicated enterprise, and one that is quite costly as well. In the U.S.A. high-speed aerosol lines rated at 160 to 280 cpm will cost about $1.0 to $1.5 million each, depending upon the degree of automation. Added to this will be the value of hydrocarbon gas-house facilities, propellent bulk tanks, compounding equipment, piping and so forth, plus any extra machines added to the production line to enable it to handle a greater diversity of products. The total cost can then rise to over $2.0 million for a first-rate facility. The initial consideration in designing a line is to consider what product(s) will be run and how much production is needed per year. A comfortable production cushion is generally built in to allow for peak periods, where seasonal sales, special promotions, introductions or other factors may double the average requirement. Many captive lines and a few lines operated by contract fillers are set up to run only one product type, such as shave creams, antiperspirants or hair sprays. These lines are relatively simple and can be run very efficiently. In one line that ran a disinfectant/deodorant almost exclusively, shift production figures ranged only about 1.5% from the average and percentage yield figures for both components and chemicals were extremely high, usually within 1% of theoretical. A few lines in the U.S.A. and many lines throughout the world are designed to run only CFC propelled aerosol products. They are not outfitted with the sophisticated gas-houses that are needed for hydrocarbon propellents. At least one line was designed specifically to run only a carbon dioxide spray product at high speeds. Over ten years later the marketer decided to add a hydrocarbon type product and was forced to purchase and install a complete new production line. Most contract fillers are preempted from filling whipped
374 The Aerosol Handbook creams, because of the need for high-speed gasser- shaker equipment, food-grade compounding and handling equipment, a suitable area for conducting food- compounding and food-filling operations and finally, the need for a large cooler in which to store finished merchandise. On the same basis, only a few specialty houses can effectively fill very small drug and cosmetic aerosols, since special fillers, clinchers and other machines are required. In the U.S.A. there are only 20 to 22 aerosol lines capable of clinching 20 mm or other size ferrule-type valves onto bottles and aluminum tubes. The filling of paints and coatings is generally regarded as a specialty business. With perhaps two exceptions, the 300 million per year U.S.A. production of these products is handled by a large group of small to moderate size establishments. The larger fillers usually have several lines, with each one made as versatile as is reasonable, and with each line complementary to the others, in order to insure a maximum level of product adaptability, consis- tant with equipment costs and other factors. Yet even for these fillers many relatively unusual products must be turned down because they cannot be adapted to the lines that are available. A listing of the different kinds of aerosol products follows, as looked at by plant engineers and other production people: a. Aerosol glass and tube lines — for 13 mm ferrule- type valves. b. Aerosol pharmaceuticals — with "white room" capability and CGMP compliance. c. Food aerosol lines — for whipped creams, requiring coolers and so forth. d. Food aerosol lines — for spray products. e. Food aerosol lines — for piston-can products, requiring gasser-plugger machines. f. Paint and lacquer lines — with clean-up versatility g. Aerosol co-dispensing product lines — "Y-shaped", rare in the 1980s. h. Miniature plastic aerosol lines — purse size spin welded base type; now rare. i. Compartmented can lines — for Sepro Cans, Alucompack Cans and others. j. Large plastic aerosol lines — for OPET bottles, with undertucked valve cup sealing. k. Lines for DME (DMO) propellent aerosols — with Class C electrical system in gas houses. 1. Lines for highly viscous products — caulkers, gel cosmetics, toothpastes, etc. (In some cases only the concentrate is viscous.) These twelve representative product types illustrate the diversity of aerosol formulations and packaging forms now on the market. Every new product makes its own particular set of demands upon compounding equipment, production facilities, or the establishment in general. For example, in the case of a 100,000 unit run of an antiperspirant, the relatively small amount of concentrate had to be made in a rather large mixing tank, relatively far away from the production line. Despite attempts to minimize losses, the dished tank bottom, handling system, filler bowl and other components held back so much product that the loss was almost 20%. Had the run been 200,000 units the loss would have been only 10%, and so forth, showing one attribute of volume on costs. Production facilities can often be modified slighdy to accommodate new product requirements. The addition of some 600 to 1000 pucks can transform a regular (tinplate) can line into one capable of handling aluminum cans. For very large concentrate fills a double-bank Cozzoli Machine Co. filler may be modified to fill half the concentrate amount through each 8-nozzle bank. However, by doing this the filling speed of the machine drops to 50% of normal. To fill a powder spray, a Diehl-Mateer or similar auger-type powder filler must be added to the line. Filamatic fillers (National Instrument Co.) are sometimes added to lines if some small ingredient must be added accurately. For a gel-type cosmetic, a case-shaker was inserted at the end of the line to mix the gel and propellent phases together. In many instances these "minor modifications" severely downgrade the production capacity of the line. If a filler expects a line to generate a certain gross income during a shift, an action that reduces overall line speed to 50% of average will also cause the services charge to double. Sometimes these speed reductions are not fully anticipated. A Chicago filler was asked to drop a mixing-ball into a rather unusual product. Not having done this before the filler merely charged for the cost of two or three additional people. But when the time came for production it was found that this operation was the limiting one. People couldn't drop balls into cans quickly enough. After a few unprofitable shifts, the firm purchased an automatic ball dropper and the problem was resolved.
Aerosol Production Equipment 375 With U.S.A. aerosol production at 70% of the peak 1974 level (prior to the CFC/ozone controversy) filler undercapacity is not normally a problem. It may become so in the future, since in the past two years a capacity of over 200 million cans per year has been lost, due to fires, plant closings, Chapter 11 bankruptcies and other causes. If a marketer needs more product than his captive facilities can produce, he has the option of employing a contract filler to provide the extra temporary volume needed. These marketer situations are brought about by peak load requirements, and also by strikes, large constructions, fire, serious equipment failures and other problems. Peak loads can usually be anticipated and can sometimes be handled by stockpiling or overtime work, both of which are increasingly expensive these days. On the other hand, smaller marketers sometimes carry "contingency thinking" too far and invest large amounts of capital in an oversized production line. Here we can only suggest, "If you have a bag of peanuts, don't buy an elephant — it may become a white elephant!" Basic plant layout must be considered carefully. Usually it is a matter of positioning an aerosol line within an existing building, or readjusting equipment to accommodate an addition to the building. There is nothing quite like an ample warehouse for raw materials and filled stock, yet this panacea is very elusive. Boards of Directors and stockholders always consider capital requests from the standpoint of Return on Investment (ROI), and warehouses are not moneymakers — at least not directly. Because of this, many marketers and fillers find themselves leasing or renting available space around town, and paying premiums for local transportation, travel time and shipping wear. Uncrowded warehouses allow better segregation of raw and filled stock, approved and rejected stock (in accordance with CGMP concepts) and filled stocks of similar appearance. Warehouse transport becomes more efficient and damage to goods decreases. At this time, experimental facts are emerging to suggest uiat flammable aerosol products require extra sprinkler protection beyond die 0.3 gpm/ft2 (12 liters/m/m2) in use for General Purpose Warehouses. Where floor-standing piles of two or diree palletloads high are involved, alcohol-based products seem to require about twice this sprinkler density, liquid petroleum liquid based products appear to require about three times this much, and antiperspirants apparently require about four times this flow rate. In addition, special Viking' 'high challenge'' 160°F (71°C) thin band sprinkler heads must be used for quick response and maximum effect. In time it is thought uiat many warehouses will install heavy duty sprinkler equipment under roof, according to needs and insurance company demands. If uiis takes place in time, then a further segregation of filled stock will be necessary for most warehouses. Whenever segregation is required the warehouse becomes less space-efficient. The U.S.A. warehouse approach is toward one large room for smaller structures and a few large rooms for larger ones. Individual areas amounting to 30,000 to 80,000 ft2 (2,790 to 7,435 m2) are not uncommon. On the other hand, die European approach is to divide warehouses into much smaller units with areas ranging from 1,000 to 10,000 ft2 (93 to 930 m2) and use not more than 60% of the floor space for actual product storage. Walls between the areas are usually of one-hour fire resistance and often are fitted with self-closing fire doors. The floor plan for a typical European type aerosol filling plant is illustrated in Figure 1 (Page 376). The main building is rectangular and has an area of about 36,500 ft2 (3,400 m2). The space allocated for the two production lines is only about 4,700 ft2 (435 m2), or about 13% of the total plant area. This particular plant was designed to produce only one product; as a result, die production lines are identical and the size of the compounding area is quite small. There is no space allocation for drums of "drain out" concentrates — product left over from previous production runs — as there would be in a plant producing a number of aerosol products. The free area to the left of die production lines is normally used for staging those components brought out of the warehouse to be used in die filling operation for that day. Any rework would normally be done in that area as well. One measure of plant efficiency is the in-plant distance that an average component or chemical must be transported before it leaves in the form of finished merchandise. In Figure 1 the average distance is 340 ft (104 m), or 84% of the length-plus-width of the structure, which is considered good. A figure of 100% length-plus-width is considered average, and many plants calculate out to 125% or more, which means extra man-hours for lift-truck drivers, and more wear and tear on both lift-trucks and stock. The lay-out in Figure 1 could probably be improved by enlarging the quality assurance and plant offices, combining them with engineering and odier plant- related offices and situating the lot above the maintenance workshop and rooms to the right. A stair-
376 The Aerosol Handbook way could provide access to the plant or the outside. The plant general manager could then overlook the production area to monitor the progress of the operation. In larger aerosol plants a more or less square construction is probably best. The production block should have the compounding area located about midway between banks of production lines, such as three aerosol lines, compounding, two aerosol lines and a liquid line. A departure must be made if the plant fills foods and/or drug products, since in these cases separate compounding facilities for each such line will be required to prevent cross contamination. If widely divergent products, such as insecticides and hair sprays are to be run in a plant, it will be highly desirable to physically separate the lines with a wall or partition. The chemical compounding area should be laid out for maximum flexibility, especially where the filler expects to encounter new formulations in the course of time. Bulk tanks of solvent should be located inside or outside, depending upon freezing point. Outside tanks should be surrounded by a low wall of reinforced concrete, an embankment or berm, able to contain the contents of the largest single tank in case of rupture, fracture or overfilling. Inside tanks should likewise be within a low concrete barrier and have the floor fitted with a drain. As a rule, solvents can be stored in plain or lined steel tanks and piped into the compounding area with ordinary steel 154 " to 2 " (38 to 51 mm i.d.) pipe. Brass or bronze valves can be used except for ammonia solutions or amines. Where food or drug products are involved these metals are no longer acceptable. Commodities like corn oil (for frypan release sprays) and isopropyl myristate/palmitate (for antiperspirants) require stainless steel #304 or #316 tanks and piping. If the filling plant produces only anhydrous household products, such as insecticides or paints, then the use of plain steel tanks and steel piping may be marginally acceptable, but otherwise, stainless steel is strongly recommended. A minimum of # 304 stainless steel should be used for all tanks, piping, pumps, filters, OFFICES •Carton Store 83 m (272'-4")- Finished Goods OUT Carton Store Valve Store Finished Goods warehouse' jHrehdi I to Warehs cu Ol 01 C (0 M CapStore -• 'i q c m Self door of fi A-Butane B-Propane C-LPG Propellent D-Propellent Scrubber Raw Materials IN Raw Materials IN Propellent Supply over Road on Overhead Gantry st=Solvent Tank 28 m (92'-0") Figure 1. Floor Plan for a Typical European-Style Filling Plant with Two Aerosol Filling Lines and Provision for a Third Line
Aerosol Production Equipment 377 homogenizers and other equipment. Hoses of reinforced neoprene rubber or Tygon (PVC) with Dracon braiding may be used for temporary connections, provided they are compatible with the product being transferred. Equipment made of #316 stainless steel has become increasingly popular for food and drug products. It is an alloy much like that of #304 but also contains 2% molybdenum, and thus has greater chemical resistance to moderately acidic sulfates, phosphates, citrates or certain other anions. It commands a premium of 10% to 25% over #304 in price and delivery times are often longer. For food products, tanks should be provided with a No. 4 (Food Grade) finish for better durability, drainage and cleaning. In the case of food items special quick-disconnect #316 piping is also required. It maybe noted that #316 is not immune to food products. For instance, saline vinegar solutions such as Worchester- shire Sauce will cause perforation of Schedule 10 (thin wall) #316 tubing after two or three months of use. The medium to large fillers routinely install 2500 to 4500 gallon (9460 to 17,000 liter) compounding tanks — although one filler (now defunct) had a giant 25,000 gallon tank used especially for the preparation of a window cleaner concentrate. When full, this tank had a gross weight of 215,000 lbs (94,000 kg). Ideally, tanks should be set upon balance platforms with the tops protruding a few feet above a mezzanine operations area. The weight is then shown on a 24" (610 mm) dial, also protruding through the mezzanine deck, close to the point where additions to the tank are made. For example, the dial may have a "face range" of 2,000 lbs (907 kg), but an additional 18,000 lbs (8,165 kg) may be cranked in, using counter-poise weights, and this additional weight shows in a small box on the dial face and must be added to the amount showing on the dial itself. The scale capacity of 20,000 lbs (9,070 kg) is the equivalent of 2,400 gallons (9,070 liters) of water or 3,040 gallons (11,500 liters) of anhydrous alcohol at ambient temperatures. In some operations, water and certain solvents are added to compounding tanks by means of ordinary or temperature-correcting gallon-metering equipment. In others, batches are made up to various heavy scratch marks on the inside of the tank. This last approach is more accurate than one might guess. Where the accuracy of a 20,000 lb (9,070 kg) scale is about ± 20 lbs (9.1 kg), the accuracy of gallonmeter and "to the scratch" additions is in the order of +60 lbs (27.3 kg) for equivalent amounts of product. In weighing materials into tanks the contents of full bottles, buckets and bags are often recorded using the net weight listed on these containers. Partial container amounts are weighed separately on a small scale and then added to the tank batch. The contents of 55 gallon (200 liter) drums are added most efficiently by raising the drum on a special hoist and pouring them into the batch tank. Food and drug products (in the U.S.A.) must be compounded using Current Good Manufacturing Practice (GMP) techniques. Everything must be weighed or measured in accordance with a Master Formula Card and reported on an Individual Batch Production Record, which is signed by the batchmaker and countersigned by a second person who was present and verified the weights or measures. This practice is a good one and is being increasingly applied in the preparation of cosmetic products. Tanks should be equipped with heating and cooling jackets, preferably of the dimple-jacket types, which are now fairly standard. The least expensive dimple-jacket designs are those with the jacket girdling the lower side- wall of the tank. The more desirable types provide jacket coverage of most of the side wall and also the bottom shell or cone. According to requirements, the dimple-jacket connections are made to cold water, hot water (as from a steam-heated tube-and-cylinder heat exchanger) or straight boiler steam. Many water based concentrates require both heating and cooling. The heating step may be done as a preliminary to forming an emulsion. The emulsion must then be cooled down to 110°F (43.3°C) or so to facilitate the addition of perfume, formalin and any other volatile or sensitive ingredients. Almost all compounding tanks are vertical and are agitated by variable speed, top-entering stirrers. Ideally, motors should be at least 5-HP, since a viscous product may come along that may require the full capacity of such a motor to stir it properly. Side- entering stirrers are certainly used, but they have several disadvantages. When the tank is 30 to 40% full they tend to throw the liquid about and unduly aerate the product. Aeration is not a problem for most products, but for gels and oxygen sensitive compositions it is certainly contraindicated on a tramp ingredient basis. Side entering agitators commonly leave quiet areas near the bottom of the tank on the far side.
378 The Aerosol Handbook In larger operations, compounding tanks should be available in different sizes, and agitation systems should utilize stirrers ranging from small propellers to wide sweeping or even wall scraping blades. The larger blades are useful in the preparation of more viscous items. Some propeller shafts carry two or three propellers at different heights. They may extend down to the bottom of the tank and may even be socketed into a female fitment there. Rotational speeds of from about 40 to 240 rpm will cover most requirements. The compounding area should be well lighted and well ventilated. Many aerosol chemicals are noted for their toxicity (a better phrase might be "physiological response factor") or for their flammability, making vapor build-ups rather dangerous. If practical, explosion-proof motors should be used throughout. Someday this may be a requirement under developing OSHA regulations for plant safety. Floor drainage should be provided, either by round drains or via narrow channels covered by gratings. In many instances, an extensive wastewater purification program must be carried out. This may involve the conversion of many acres of ground into settling lagoons, aeration ponds and other water collection areas to facilitate bacterio- chemical clean-up and thermal equilibration programs. Analyses for BOD, COD, pH, trace elements and other factors are made frequently to control the operation of the system. One factor that truly characterizes an aerosol filling plant is the presence of large quantities of propellent — sometimes 300,000 gallons or more at a time. The largest inventories are normally carried by the leading contract fillers, as they struggle with the task of pro- Figure 2. Propellent Blending System Schematic diagram for batch and in-line propellent blending systems. In-line blending eliminates tanks and complicated piping for mixing chemical products. IN-LIKE BLENDING ELIMINATES TANKS AND COMPLICATED PIPING. viding an ever-increasing diversity of pure and mixed propellents to their customers. The aerosol industry in the United States has been slow to change over to inline propellent blending, preferring to do their own batch blending or else have their suppliers undertake this for them. However, in-line blending, despite the expense and other problems, must come. The advantages can no longer be denied or discounted. Economic justifications for in-line blending are many. Foxboro, which has installed many propellent blending systems, claims a 25 % reduction in tankage is typical. In addition, blending time is reduced over 50%. There is a wide range in the cost of blending equipment, depending on the quality of the equipment and the number of optional devices included. Mechanical, electronic or pneumatic controls are used to maintain the proper ratios between the individual components of the product. Keene Corporation (Greenville, Tenn.) supplies a basic mechanical system which costs about $9,800 per stream and which has a blending rate of 0.1 to 250 gpm. Digital Blending Systems, Inc. (Providence, RI) offers a moderate size electronic blender for two components for about $25,000 or so. Foxboro Corporation (Foxboro, MA) and the Fischer & Porter Company (Warminster, PA) also supply electronic systems. Blending accuracies normally range between ±0.25 to ±1.0%, although minimum expense installations can go to ±1.5% Other economic advantages result from reduced propellent inventories, less labor, lower propellent loss, fewer chances for human error, reduced analytical requirements, more accurate blending and simplified piping arrangements. Aerosol plants which do no blending usually have losses of 7.5 to 8.0% propellent per year. Those with bulk tank blending facilities usually lose more than 9.0% per year. There is always the odd blend left over from a packaging run, which may not be used again for several months. In a high quality operation this would either be saved or blown to the atmosphere in order to free up the tank. In a low quality operation the blend is sometimes added to much greater volumes of similar propellents or blends on the basis that the difference will not be apparent. The magnitude of propellent losses may seem surprising to some, but it is factual, having been reported in plant after plant. Most of the loss occurs at the gassing machines. Depending upon the gassing adapter, the amount of propellent lost to the atmosphere when separation of the head from the can takes place will
Aerosol Production Equipment 379 amount from 0.07 to 2.8 ml. Adapters that make a direct connection to the valve stem cause the least loss, but all the liquefied propellent, under a liquistatic pressure of 800 to 1000 psig (5.52 to 6.90 MPa), must pass through the stem orifice and tailpiece orifice. This may have a severely limiting effect upon production rates. In addition the valve button will have to be tipped onto the stem later on, and possibly oriented to the dip tube curvature. One of the least efficient gassing adapters is a standard design with a large rubber boot that makes a seal at the bottom of the valve mounting cup and depresses the valve stem liquistatically. In the case of a typical pedestal opening of 0.130" (3.3 mm) the actuating pressure exerted by an 800 psig (5.52 MPa) liquistatic propellent pressure calculates to 10.6 lbs (4.82 kg), which is more than enough to open both vertical and toggle-action valves. A substantially improved adapter design for through-the-valve (T-t-V) gassers is one that effects a seal near the top of the side wall of the valve cup pedestal by the inward compression of a small neoprene "0"-ring. An instant later the "X"-slotted top of the adapter cavity actuates the valve button or valve stem mechanically, to allow gassing to occur. At the end of the injection phase the stem is allowed to move upward to reseal the valve, after which the connection with the cup is broken. By working in this fashion much less propellent loss results when the gassing head lifts off the container. In addition, valve shut-off is more positive and this results in more accurate propellent weights. These two adapter designs can be compared with respect to loss difference by filling the respective cavities with water and measuring the increase in weight. The difference amounts to about 1.2 ml. While this may not seem too significant, for isobutane A31 it amounts to 0.66 g/can at about 70°F (21.1°C) and if 100,000 cans are run during the shift the loss from this cause alone will be 66 kg or 31.7 gallons of propellent at a current (1982) cost of $34.50. Other losses of propellent arise from leaking molded cap seals in the gassers, the venting of pipeline contents to the air before changing propellents in the gas house, leaks at pump seals and so forth. In the U.S.A. at least, no heel credit is given for the small portion of propellent returned to the supplier in commercially emptied tank trucks and tankcars. Because of this most fillers attach a compressor to the exit line of the emptied vehicle and suck out the remaining material, down to a 23 " Hg° (-77.7 kPa) vacuum or so. In a typical tank truck of 9200 gallon (35,000 liter) capacity, isobutane A-31 gas at 70°F (21.2°C) will weigh 576 lbs (261 kg). If 76.8% of these vapors can be drawn out by the filler, the net gain is 95.4 gallons (361 liters) of liquid, for a current (1982) value of $104. This analysis assumes an absence of residual liquid, but in fact there always is a certain amount of this also, which would be vaporized and the vapors partially withdrawn, adding to the savings. The Aerosol Production Line The average aerosol production line is composed of ten to twenty pieces of equipment linked together by conveyors. Perhaps the simplest operation would be to stretch everything out into a straight line, but this might run into several hundred feet and make it difficult for supervisors and maintenance men to get from one end of the line to the other. The more practical approach is to use a layout with a minimum of corners and to provide these corners with small rotary discs to carry the cans around and eliminate dead-plate problems. Aerosol lines are usually categorized according to speed rating in terms of number of units per minute. Four classifications are considered, as illustrated in Table I. There are many circumstances under which a high speed aerosol line will be able to operate only at a fraction of its nameplate capacity. This is more commonly encountered by contract fillers than marketers, since fillers must try to handle many kinds of products and packaging requirements on a limited number of lines, some of which do not "fit" as well as others. In one instance, a 160 cpm rated line was slowed to 78 cpm because nitrous oxide (N2O) had to be injected by means of an Autoproducts, Inc. (formerly Andora Automation, Inc.) gasser-shaker. In another, it was slowed to 105 cpm because the gel-type concentrate had to be shaken mechanically into the propellent phase and four Red Devil (single case) shaker machines were all that were available. In a final example, the same line Table I Production Line Ratings According to Speed In cpm Type of Container Tinplate cans Aluminum cans Glass bottles Plastic coated glass Plastic Slow 0-50 0-30 0-25 0-25 0-25 Production Speeds (cpm) Moderate 50 - 125 30-80 25- 75 25-70 25-75 High Very High 125 - 200 200 - 500 80 - 125 125 - 175 75-110 — 70 - 100 — 75-110 —
380 The Aerosol Handbook was reduced to a speed of 120 cpm because there was not sufficient length on the packaging line for people to perform a complex assembly operation any faster than this rate. Viscous concentrates, large filling weights, excessive quality assurance requirements, paper labeling and other factors also reduce line speeds. Paper labeling will lower rated speeds by 6 to 10% as a rule, but "problem" labels, such as those which are a little too tall, will force larger reductions. Some years ago, the through-the-valve (T-t-V) filling of valves occasionally caused slow-downs due to reduced gassing rates. This was particularly true for certain valves with a restricted tailpiece orifice. By now there is such a diversity of pressure-filling valves, with gassing rates of faster than 300 ml per second, that the limitation has just about vanished. In one unique situation the removal of perchloro- ethylene from a cleaning product, and replacement with additional odorless petroleum distillate, caused the concentrate volume to be so large that the head space in Figure 3. Plastic Container Carrier Pucks the can was reduced to below the critical level of 15v% that must be available for efficient "instantaneous impact gassing" of CO2. During the summer months, the product could not be run in this manner without first cooling the concentrate to enlarge the headspace in the can. The production rate became a function of how rapidly the available refrigeration unit could draw the concentrate from ambient to about 40°F (4.4°C). Tinplate cans can be run at very high speeds, partly due to the fact that they are ferromagnetic. They can be held down and guided by magnetic can handling equipment when necessary, as for instance in most hot tanks. In addition, they are cylindrical, which greatly aids can handling. There are a number of aerosol production lines in the U.S.A. which operate at about 280 cps, plus a few which use the Kartridg Pak 18-head Under-the-Cap (U-t-C) gasser to reach speeds of about 360 cpm. Reportedly the fastest aerosol line in the world is a captive line in Holland, with speeds variously reported as 450 to 550 cpm. Aluminum cans and tubes often require insertion in polyethylene or nylon pucks for both stability and magnetic hold-down. Two puck suppliers are mentioned in the chapter on metal aerosol containers. Figure 3 shows several pucks distributed by Terco, Inc. (Schaumburg, IL). Some aluminum tubes are so tall (height/diameter = 8) that pucking is mandatory to prevent fall over. But in other cases, lines that are designed especially to handle more reasonably proportioned tubes can do so without the need for pucks. D.H. Industries Ltd. (England) conveyor systems, for example, are engineered to very close tolerances for aluminum tubes, to prevent bouncing and moving about. Delrin starwheels are used for in-feeds, as well as converging and diverging operations with a typical clearance of only 0.008 " (0.2 mm), and deadplates are very small and adjusted for the smoothest possible transfer. The feed worms are kept as close as possible against the backup plates. Variable speed drives and photoelectric controls are also useful in such lines. In the case of plain glass aerosols, it is important to maintain the pristine exterior surface of the glass. For this reason pucks are strongly preferred, although they are not always used, especially in the case of round bottles on manually-operated or low speed lines. Plastic coated glass can be handled about like aluminum; without pucks if a sufficiently sophisticated transfer system is used.
Aerosol Production Equipment 381 Aerosol production lines can be categorized according to design, as summarized in the following listing. Speeds in terms of units per shift are also included. a. Laboratory units. 800 to 2,500 ups. b. Manually operated lines. 7,500 ups. c. Single indexing, in-line assemblies. 14,000 ups, or 35 upm d. Double-indexing, in-line assemblies. 28,000 ups, or 70 upm. e. Rotary operations. 14,000 ups and higher. (Single and double indexing) The so-called laboratory units can be used with surprising effectiveness for simple operations. It is thought- provoking to see certain plant operations in Mexico, South America and Africa, where one or more moderately sized rooms are set aside for the filling of glass or aluminum tubes by one or two people. To make a typical cologne, the concentrate is added volumetrically to the empty unit with a buret, filled every few minutes from a copper tube extending out through the wall of a refrigerator. Very cold CFC propellent is then added to a preset gross weight. The container is then crimped, allowed to warm up and bulk-packed for shipment to the marketer. One person can do as many as 1250 units per shift on crude lines of this type, making direct labor costs roughly comparable with those of much larger aerosol lines. The manually operated lines consist typically of a lever-operated filler, a crimper and a gasser, mounted separately on a work table, sometimes followed by a three-basket hot tank. The lines are unusually air- operated. One is illustrated in Figure 4. If the program is simple, two people can often produce between 6,000 to 8,000 units per shift. On the other hand, if paper labeling or other auxiliary operations are required, either more people will be needed or the operation will have to proceed more slowly. The individual operating units can be of many makes and descriptions. One good way to combine the crimping and gassing operations and gain a large measure of packaging latitude is to use a single-head Kartridg Pak U-t-C gasser. It is not inexpensive. With the vacuum pump, Grayco high-pressure propellent supply pump, and sometimes other accessories, it can cost about $16,000. Single-indexed lines are available in both in-line and rotary styles. Sometimes the two forms are mixed, so that an in-line filler will be used with a rotary gasser. Straight line indexing lines require more space than rotary equipment. But maintenance is generally easier, since there are fewer filling, crimping and gassing heads, especially when comparing larger lines. The best drives use the so-called Geneva design, which provides accurate container positioning with a smooth, fast, non-jerky transfer motion. It is much better than the air-cylinder crank operated drives. Electric operated drives are always preferred over air- operated types, regardless of the actuating mechanism. Most indexing machines have an electrical inter-lock control circuit, that prevents recycling until the slowest component has completed its operation. This system results in automatic adjustment to the maximum production rate of the machine, without regard for container volume, concentrate viscosity or several other factors. It also insures against slack-filled units by making adequate time available for each operation. To eliminate production problems the fillers and gassers should be provided with container-sensing valves that provide a no-container, no-fill operation. A single-indexing, single-line, in-line system will produce up to about 35 units per minute. A double- indexing, single-line, in-line set-up will produce twice that rate, by conducting operations on two units at once for each operating step. The fastest in-line assembly is the double-indexing, double-line, with operating units on both sides of a common frame or machine table. These lines have nameplate ratings of about 120 units per minute, but can often be coaxed to go about 20% faster than that by means of various drive adjustments. However, they may wear out more rapidly on that Figure 4. Manual Production Filling Line Product is transferred manually to each step of the operation. Pcopellant charger Product filler
382 The Aerosol Handbook MODEL DSLD DlU^rnmK CRIMPERS (4) PROPEILANT REJECTORS (4 OPTIONAL IN-FEED | 1 °Ml F'llERS «5SSg?!« TRANSFER DISCOR CONVEYOR DOALPURGERS CHARGERS<4) FEEDER DRIVE OR CLEANERS (2) MODEL SLD 3' 1 r 2-4" "-—ft ; M$mmtiT~a3Z. Ji S i' PH »!!<9l:T "~"i INFEEO TIMING SCREW DUAL FILLERS PURGER Figure 5. Nalbach Design of Single and Double Row, Double-Indexing Lines Figure 6. Rotary Line Including Filler/Crimper/Gasser With single-indexing, this line achieves speeds of 35 to 40cpm; with double-indexing, speeds move up to about 70 cpm. Design by John R. Nalbach Engineering Co. N Explosion proof hydrocarbon charging room Automatic aerosol valve sorter and inserter Packaging room wall Can de-palletizer Figure 7. Double-Indexing Loading Line John L. N«lb»ch Engineering Company, Inc. basis. Examples of single-row and double-row double- indexing lines are illustrated in Figure 5. Perhaps the simplest rotary line is one where the filling, crimping and gassing operations are all consolidated into one machine. In U.S.A. operations the machine is normally placed in an explosion-proof hydrocarbon charging room, or gas house, preferably outside the main production building. These lines normally operate at from 35 to 70 units per minute and are readily available to containers of different sizes and constructions, as well as to the requirements of a wide variety of different products. A schematic of such a line is shown in Figure 6. The higher speeds require double- indexing at the rotary filler/crimper/gasser. As an alternate, the key steps can be handled by a combined filler/crimper rotary, followed by a rotary propellent charger. Again, bom single and double- indexing variables can be obtained from several suppliers. A double-indexing line of this kind is illustrated in Figure 7. This line has a rating of 40 to 50 units per minute. A similar, single-indexing line is rated at 25 to 30 units per minute. It has only a single-track hot tank, no disc accumulator and a simple 36" (914 mm) disc-type container feeder. The largest aerosol lines are almost always rotary in design, since in-line equipment seems to have a practical limit of about 140 to 160 units per minute at best. Rotaries may go to three times that rate and are much more space efficient. In die U.S.A. large rotary lines seem to center around high-speed rotary gassers made by The Kar- tridg Pak Co. (Davenport, IA). There are two types: Under-the-Cap (U-t-C) and Through-the-Valve (T-t-V), in both 9-head and larger models. They are discussed later on. A number of machinery suppliers offer "core assemblies": an integrated single piece of equipment for doing several operations at the heart of the aerosol production operation. Figure 6 illustrates this machine in layout form, if the in-feed transfer disc is omitted. Five operations are performed by this composite unit. A similar in-line unit by the J.G. Machine Works, Inc. is shown in Figure 9. In the case of rotary equipment an outstanding example of the "core assembly" principle is the Star Pak M-20 Filling Machine by Aerofill Ltd. (England). The base unit accommodates six metering heads and seven omer heads and will produce at rates of 20 to 45
Aerosol Production Equipment 383 cpm, handling either cans or bottles. A twin unit has double this range. Typical of the operating heads that can be integrated with this machine are concentrate fillers, a can cleaner, ball dispenser, valve inserter, valve sensor, crimper or vacuum crimper, propellent fillers, valve rim stamp coder, checkweigher and liquid purger. With optional extras the machine fills slurries, powders or compressed gases. Odd shaped bottles can also be accomodated. The machine is illustrated in Figure 10. In some instances the' 'core assembly'' is extended to include machines normally before it and behind it on the production line; e.g. an "extended core assembly". All three devices are bolted directly together. In the Terco, Inc. unit shown in Figure 9 only the hot tank is conveyorized. Individual' 'core assemblies" will only handle up to 45 or 60 cpm, which limits them to moderate speed operations. For faster lines the concept must be abandoned in favor of individual machines. Here again, a number of suppliers, such as Aerofill, Ltd. (England), The Kartridg Pak Co. and Coster Aerosol Filling Equipment Division (Italy) can produce high-speed machines. Higher speed lines are often assembled by selecting the best filler, gasser, case packer and other components, setting them out in a certain arrangement, Figure 8. Rotary Filler by Terco, Inc. Rotary filling machine with water bath will process up to 40 cpm. It is air operated. All stations interlocked so slowest operation controls overall output speed. Machine consists of 4'x6' table, coder, 2 product fillers, vacuum crimper and 2 propellent chargers. Figure 9. Core-Assembly Machine High-speed line by J.G. Machine Works, Inc. The core-assembly machine is the heart of an aerosol filling line. 1 ••»• \i 1 I »■ 1 Figure 10. Star Pak M20 by Aerofill, Ltd. Lower photo shows the Star Pak filling machine with automatic valve inserter/sorter. Photo above shows the working heads in more detail. The machine can accomodate six metering heads and seven other heads. It is the core assembly unit of any associated aerosol line. IW1A«*f* ALVft M*i'Hltt'lll|»n I! f i^kll-
384 The Aerosol Handbook and then linking them together with conveyers. Some lines are far more mechanized than others, and the extent to which mechanization is introduced depends largely upon the attitude of the company management and the amound of funds available. A minimally mechanized 200 cpm production line can be installed for approximately $500,000 whereas costs for the highly mechanized equivalent can total up to $850,000 or so. As more machines are added, the average production rate drops somewhat, more warehouse space is consumed and maintenance costs are increased, but the tremendous savings in labor more than justify these shortcomings. Individual machines are often purchased on the basis of pay-off time evaluations. If a rotary valve inserter costs $65,000 and saves the expense of six extra people on the production line, using a two-shift analysis, it is possible to calculate how quickly the $65,000 can be saved in labor in order to justify purchase. If the six workers were each paid $150 per week, Figure 11. Lehn & Fink Hi-Speed Aerosol Line © ® © List of Production Equipment 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. II. Depalletizer. Unscrambler. Can Cleaner. Can Bottom Coder. Concentrate Filler Sorter Station of Valve Inserter. Hopper of Valve Inserter. Varidyne Motor. Electrical Control Panel. Valve Inserter. Repair Benches. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. Undercap Filler. Propellent Pump. Heat Exchanger. Checkweigher. Water Bath. Capper. Cap Sorter Station. Accumulator Table. Case Packer. Box Former. Case Sealer. Compression Unit and Case Coder Station. Palletizer. to which a 50% benefits and overhead figure could be added, the total cost per week for these people would be $1,350. The pay-back or Return On Investment (ROI) period would then be about 48 weeks. This is normally sufficient justification for purchase, even in times of fairly tight money. But if the same plant were only running on a one shift basis, with no outlook toward two shifts, the ROI period would become about 96 weeks, which might be considered too long. Other important factors involve the financial condition of the company and its access to the required capital. The design features of an aerosol line can be greatly simplified if only one or two produts are to be run on it. A classic example of a captive line of this kind is the high speed facility installed by 1966 by the Lehn & Fink Products Corp. at their plant in Lincoln, IL. It runs almost exclusively, even today, on a single hydroalco- holic product that is marketed in three can sizes. The line is rated at about 160 to 210 cpm, depending upon package size. Changeovers are in the area of thirty per year and require about 70 operator-hours each. The line is located in an area of about 60 x 90 ft (18 x 27 m). The original design, illustrated in Package Engineering many years ago, was so well conceived that relatively few changes have been necessary. One involved a necessary propellent change. Another was to add some sophisticated new equipment, such as a Currie Machinery Co. pallet loader. The basic "U"-shaped layout provides the best communications and control capability of any design, and this general shape was used by Lehn & Fink engineers, as shown in Figure 11. Because of its limited product range, the Lehn & Fink line does not include such items as a paper labeler, auxiliary concentrate filler, hydrocarbon gassing capability (to date) and can shakers. However, the contract filler nearly always has to build these extra facilities into his aerosol lines to gain added flexibility. In many instances, a new line may be installed with spaces left for future additions of packaging machinery. In a typical example, room was left near the end of one aerosol line for a future box former, case packer and palletizer. It is important to consider space requirements for accumulating tables, mechanized, manual or automatic weigh stations, record desks, repair benches, heat exchangers, vacuum pumps, control panels and one or two satellite production control stations when laying out a new line. Ample room should be provided for special packaging operations, such as unit boxing, addition of
Aerosol Production Equipment folders, hand cleaning, hand application of special actuators, domes or stickers, and unique display case packaging programs. These "extra allowances" may add significantly to the total space requirement, but they nearly always pay off handsomely in the long run. Aerosol lines are frequently tailored or modified to perform specific operations. A line used only for aluminum or glass containers will have no provision for a depalletizer, since a puck-type carrier is normally used. Lines used for the production of whipped creams will not have a gasser in the usual sense, but either a rotary gasser-shaker for moderate or slow speed operations, or a U-t-C gasser with either an ' 'instantaneous impact gassing" modification or "saturation" accessory for higher-speed productions. A can cleaner would have no real value on a tube and bottle line unless it is designed specifically for these containers. A U.S. Bottler's cleaner is available which grips these particular units, inverts, blows and then vacuum cleans each one individually. This is now done in place of the integrity check for glass, where the bottles were pressurized to 120 to 150 psig (827 to 1034 kPa) with compressed air or nitrogen, and it was assumed that any lint, corrugate dust or other light materials would be blown out when the pressure was suddenly released. Special requirements are often handled by the addition of mobile equipment to the production line. The line is modified to readily accept insertion of such items as a paper labeler, auxiliary concentrate filler, ball dropper and accumulator. If the equipment is not needed elsewhere in the plant, the mobile units may be left in the line as non-functional fillers. An individual line may be required to handle concentrate fills of from about 6 to 600 g, as well as propellent fills over a similar range. This is usually accomplished by the use of special orifices and different sized charging cylinders, so that greater absolute fill weight accuracies can be obtained for the smaller fill requirements. Very small aerosols are sometimes filled to tolerances of as little as ± 0.05 g for both concentrate and propellent portions. In a marginal situation a 2 Av. oz, (56.7 g) shave cream had a two-sigma propellent fill weight specification of 1.93 ±0.6 g. The contract filler could not meet this requirement with high speed T-t-V equipment. The best that could be managed was a two-sigma tolerance of +0.85 g. Figure 12 shows that too little propellent would result in an overly dense or soupy foam, while too much would cause the foam to be dry and hard to apply to the face or body. Rather than have the product filled with extreme accuracy, but on a slower line and 1.0 1.5 2.0 PROPELLENT WEIGHT (g) Figure 12. Product Acceptability vs. Weight of Propellent A-46 for a 2 Av. oz. Shave Cream therefore at an increased cost, the marketer decided to move the target fill upwards by 0.20 g. The histogram for a specification of 2.13 ±0.85 g is not shown but is still almost entirely within the "relative acceptability" curve. This situation would be totally unacceptable for aerosols with ±0.05 g tolerances. In such cases fillers and gassers with unusual accuracy are needed. Pamasol and a few other firms supply this equipment, often for Class 100 clean room pharmaceutical productions and less frequently for meter-spray perfumes and a few other products. The larger equipment suppliers will often provide prospective customers with a lay-out of a proposed aerosol line as part of their bidding and business solicitation programs. Figure 13 (Page 386) illustrates a production line designed by Aerofill Ltd. (England) for a marketer who wished to make only one aerosol product at rates of 120 cpm minimum. Rotary equipment is used for filling, crimping and gassing. In contrast, a highly versatile high speed line consists of a relatively large number of individual items of production equipment. Auxiliary equipment, such as pumps, filters, electrical control boards and hot tank heat exchangers are often located nearby. Figure 14 shows such a line. A summary of the production equipment is given in the accompanying list (Page 387). A fully versatile aerosol can production line should include the following machines or operations: a. Semi-automatic depalletizer. b. Can cleaner.
386 The Aerosol Handbook c. Can coder. d. Empty can counter. e. Ball dropper Optional. f. Powder filler. Optional. g. First concentrate filler - volume to 250 ml. h. Second concentrate filler - volume to 750 ml. i. Line speed indicator. Optional. j. Automatic concentrate checkweigher. Optional. k. Valve inserter. 1. Valve cup depresser - or cup seater. m. Accumulating table. n. Under-the-cap (U-t-C) 9 or 18 head gasser. o. Through-the-valve (T-t-V) 12 head gasser. p. Rotary 12 or 18 head gasser-shaker. Optional. Figure 13. Lay-out of an Aerosol Production Line Description: 1 ■ Rotary Unscrambler-Extended loading 3-6/12 Head Rotary Product Filler with Guard 7-6/12 Head Rotary Vacuum Crimper 14 - 6/12 Head Rotary Propellent Filler with Guard 21 -Checkweigher 23 - Six Lane Test Bath 25 - Rim Coder 27 - Tamperproof Seal Applicator Aerosol line by Aerofill, Ltd. of England is designed to run one product at 100 cpm. q. Automatic product checkweigher. r. Valve button tipper. s. Can washer. Optional. t. Hot tank and blow drier - 4 to 6 lane. u. Accumulating table. v. Wrap-around paper labeler, on conveyor shunt. w. Capper. x. Overhead compression unit - to seat caps. y. Assembly, cleaning, inspection and packing table. z. Cartoner- 2, 3, 4, 6 and 8 pack. Optional aa. Case packer. bb. Case sealer and compression unit, cc. Case coder, dd. Case counter, ee. Case shaker. Optional. ff. Case palletizer frame - manual packing. Notes: Additional accumulators may be added if desired, such as just before the can washer. Box formers, sorter stations and other units not in the main sequence have been omitted. Conveyors and smaller quality assurance devices have been omitted, such as a no-button reject station prior to the capper. Items designated as "optional" are often omitted, depending on product mix or preference. AEROFILL LTD. Y«»/ol/
Aerosol Production Equipment 387 A smaller size rotary line, with far fewer stations, is shown in Figure 15. It has a working capacity of about 120 cpm, with six filling heads mounted on a nine- station U-t-C. The line is designed for straightforward, easy-to- handle aerosol products. It has almost no accumulating (surge table) space. There is no provision for manual operations except for on-loading empty cans, packing, sealing and pallet-building. About seven people are needed to operate this line, as a minimum. Aluminum cans with one-inch (25.4 mm) openings can be produced on versatile can lines of the types shown, such as the one in Figure 14, using puck containers, but for 13 mm, 20 mm and similar small size tubes and bottles a special line is required. The Schering-Plough Corp. (Pharmaceutical Division) tube line in St. Louis, MO is an outstanding example of what is required. The product run on this line is Figure 14. High Flexibility Production Line List of Production Equipment 1. 2. 3. 4. 5. 6. 7. 8. 9. :'0. 1 1. 12. 13. 14. 15. 16. 17. Busse Depalletizer Overhead Conveyor. Unibelt Conveyor Unibelt Conveyor Fleetwood Can Cleaner and Blower Unit Conveyor and Worktable Kiwi Coder Conveyor and Worktable Cozzoli I6-Head Concentrate Filler Conveyor and Six-Foot Manual Weigh-Table By-Pass Conveyor PMC Valve Inserter—Rotary Applicator PMC Valve Inserter—Disc Sorter PMC Valve Inserter—Valve Supply Bin Outside Conveyor—Covered Head Outside Conveyor—Covered. Inside Worktable Double-Width Conveyor 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. KP "Undercap" Gasser and Propellent Reclaim Conveyor "Metramatic" Checkweigher Conveyor and Worktable; Two Track Split at End Double-width Outside Conveyor—Covered Four Track Splitter, Terco Hot Tank and Blowers Can Accumulator—Six Tracks, Eight Feet Long By-Pass Conveyor and Blowers. Labeler Insertion. Conveyor, Blowers, Electric-Eye Button Detector and Discard Table "Pneumacap" Capper Conveyor With Compression Wheel and Worktable Box Former SKC Automatic Gluer, Compression Unit and Case Coder NOTE: Work Tables Are Not Shown on Drawing Optional pack-off table ■ Cap seater Single line unscrambler Can cleaner , Product filler Hydraulic pump /ri,Vacuum Q \J pump Undercap Conveyor dnver Overcapper Can drVer Cap sorter 20-foot waterbath Figure 15. Simple Rotary Line, Rated 120 CPM The Kartridg Pak U-t-C gasser in this line is outfitted with six filling heads in the 1,2,4,5,7 and 8 positions on a standard nine-head frame.
388 The Aerosol Handbook "Vanceril", a 54 Av.oz. cannister of inhalant, where the drug is suspended in a mixture of P-l 1 and P-12 and dispensed via a metering valve. The line components are listed as follows: a. Unscrambler. Rondo b. Accumulating turntable. c. Tube cleaner. U.S. Bottlers d. Filler. Pamasol i. Product filler turret. ii. Valve seating transfer disc, iii. Crimping turret, iv. Gassing turret. e. Checkweighers - two required. Anritsu f. Printer. A.B. Dick g. Heat tunnel leak detector, h. Bulk packaging station. Standco The line normally runs at 110 to 120 tubes per minute and is crewed by five people. The bulk containers of finished aerosols are transported to another area of the plant for final pressure checking, assembly to the inhaler nozzle and final packaging. The Pamasol filler operates within an enclosed area that is the practical equivalent of a Class 100 clean room. In addition, it has its own enclosure and a laminar flow of air under positive pressure. D.H. Industries Ltd. (England) was the primary contractor for the equipment. Individual Production Equipment Items General descriptions and sources of the more important pieces of production equipment are of interest to persons wishing to purchase or improve aerosol installations. Although a number of suppliers are cited, listing such names should not be construed as any particular recommendation by the author, expressed or implied. Can Depalletizers and Other In-Feed Equipment Most tinplate cans are now shipped to fillers in palletized form. In large-scale operations these standard units are mounted on the in-feed conveyor of an automatic depalletizer and then hand stripped of their bandings, polyethylene wraps and top sheet of chipboard. The hoist unit then moves the palletload upward until the top layer of empty cans is level with an accumulating table about 48 " (1.22 m) wide. By pushing a button on the control board an operator causes a rake to move over the cans and draw them forward, onto the metal belt conveyor that feeds a rotary disc which then supplies cans to a single track conveyor leading to the production line. After the layer of cans has been transferred, the second layer of chipboard is removed from the palledoad, it is raised another tier, and die rake again sweeps them onto the broad metal mesh belt. In some installations mirror imaged units are placed about three feet (0.92 m) apart so that one operator can handle both machines at once. In one case such a duplex installation handled over 400,000 cans in a 21 hour period. A popular automatic depalletizer is one made by Busse Bros., Inc. and known as the Busse Hydraulic Empty Can Depalletizer, Model WD-300. Another is made by Coster Aerosols Ltd. (England), known as their FIMS 1200, rated at 400 cpm. Container in-feeding on a less costly scale is done by rotary discs, multiple conveyors, conveyorized rotary discs, unscramblers and semi-automatic depalletizers. The rotary discs consist of XA " (6.4 mm) thick sawed circles of steel or stainless steel from 36 " to 48 " (0.92 to 1.22 m) in diameter, let into the countertop of a stationary tray, as shown in Figure 16. Cans are unloaded onto the tray by hand and pushed onto the disc, which then feeds either one or two single lane conveyors. The smaller disc will handle at least 40 cpm and the larger one will do about 60 cpm. These can feeders are the least expensive ones available. The next more sophisticated can feeder is a device like the above, but where the short stationary tray is replaced by a wire mesh belt that can hold 500 to 1000 Figure 16. Economical Tray-and-Disc Can In-Feeder Unit
Aerosol Production Equipment. 389 cans and feed them onto the disc as they are needed. A step beyond this involves the integration of the belt-fed disc unit with a three-sided pallet guide fitted with a hydraulic scissor-lift, thus creating the semi-automatic depalletizer unit. Cans are unloaded against either the side or the end of the wire mesh conveyor belt, from which they enter the disc and then the conveyor system. Since full palletloads are about 54" (1.37 m), which is obviously higher than standard conveyor heights for production lines, two designs for semi-automatic conveyors have been developed. In what is often called the Terco design the wire mesh belt and disc are elevated to about 48 " (1.22 m) to accomodate the top layer of cans on a palletload. The disc then unloads onto a magnetic lowering conveyor section to reduce the height to the 34 " to 38 " (864 to 965 mm) range used for the production line. In the so-called Nalbach design the pallet guide is positioned at the edge of an 18 " (457 mm) deep hole. The palletload is moved across the hydraulic jack, which is then lowered into the pocket or hole until the top row of cans is even with the wire mesh conveyor belt and ready to be unloaded. Air powered clutches and sensing valves are used to integrate the operations. An illustration of the Nalbach semi-automatic depalletizer is provided in Figure 17. Figure 17. Semi-Automatic Depalletizer Unit by John R. Nalbach, Inc. Can Cleaners These devices were unknown on aerosol lines of the 1950s, became optional in the 1960s and were standard in the 1970s, at least for lines producing foods, drugs and cosmetics. They generally function by inverting the can over a blast of dry, filtered air, so that not only are dust, lint, cardboard fibers and other lightweight trash removed from empty cans, but heavier items as well. Things like solder pellets, a magnesium rod from a can- packing rake and even a pencil stub have fallen out of inverted cans during cleaning. Tinplate cans or pucked aluminum cans can be inverted using magnetic wheels. Non-magnetic containers can be inverted by squeezing them between two long "inner tube" sections as a carrier mechanism. Smaller units are often cleaned without inversion. A magnetic wheel unit is sold by Fleetwood Systems, Inc. (Countryside, IL) and several other suppliers. Can cleaners have been identified as a major potential source of tramp moisture in aerosol cans. Air compressor tanks always have some condensed water in the bottom. Unless it is effectively filtered out using baffles and desiccants, water can be blown into cans from the air nozzles, causing contamination, can rusting and even perforations. In one instance a stuck indicator dial on a desiccating unit eventually permitted water to travel dirough the air line undetected. It entered aerosol cans in amounts from about 0.01 to 0.80 ml and ultimately caused the rejection of almost 200,000 units due to internal rusting and product discoloration. I ,?l I JJliJi ' ' t f ■'J ' i;'.Til i » ' i | \ Can Coders A very large number of can coders, sometimes called code daters or bottom coders, are supplied for aerosol filling operations. Perhaps the most widely used are machines made by the Kiwi Coder Corp. (Chicago, IL). With a few exceptions they all do a good job, requiring very little maintenance. Typical pieces of equipment are: a. Model 631-A Production Flow Bottom Coder — Control Print Corp. (Cedar Grove, NJ) Speed to 550 cpm. b. Model AO Date Coder — John R. Nalbach Engineering Co., Inc. (Chicago, IL) Speed to 60 cpm. c. Kiwi Model 15-36-B Automatic Hi-Speed Coder — Kiwi Coders Corp. (Wheeling, IL) Speed to 120 cpm.
390 The Aerosol Handbook d. Kiwi Model 15-72-B Automatic Hi-Speed Coder — Kiwi Coders Corp. (Wheeling, IL) Speed to 400 cpm. e. Ertel Bottom Coder — Ertel Bottom Coder — Ertel Engineering Co. (Kingston, NY) Speed to 120 cpm. f. Markocoder Model BD-1 Bottom Coder — Adolph Gottscho, Inc. (Union, NJ) Speed to 250 cpm. g. Markocoder Model SWB Bottom Coder — Adolph Gottscho, Inc. (Union, NJ) Speed to 550 cpm. h. Code-A-Top — M.E. Cunningham Company (Ingomar, PA) Speed over 100 cpm. i. Code-A-Can; Mark II — M.E. Cunningham Company (Ingomar, PA) Speed to 136 cpm. j. Code-A-Can; Model 66 — M.E. Cunningham Company (Ingomar, PA) Speed to 500 cpm. on single line of cans. k. Top Bead Code-A-Can — M.E. Cunningham Company (Ingomar, PA) Speed over 100 cpm. Machines "a" through "g" function by rotating sets of pre-inked rubber type against the bottom of aerosol cans. Either Baselock or Kiwi channel type is used in various heights. The machine in "h" cuts the code into the side wall of ferrule-type valves and thus provides a way for indelibly coding glass bottles. The Cunningham machines, "i" and "j" operate by forcing a marking head hard against the vertical wall of the bottom double seam, so that a series of letters and numerals are impressed horizontally into the can metal. The machine in ' 'k'' is similar, but inscribes the top head. In the U.S.A. there has been a strong preference for inked-on codes. At first there were some groundless concerns about the continuing hermetic integrity of coded bottom seams, but now the greatest fear is that a customer will reject aerosols with an indelible and incorrect punched-in code. With open code dating and rigorous government requirements the need for correct coding is now more critical than ever before. At least with inked-in codes any incorrectly marked containers can be corrected in the rework area, with solvent and hand restamping. Recent developments in this area include the so- called microscopic coding, using extremely small numbers and letters, and also laser beam coding. Compact laser coding systems are available from Laser Applications Ltd. and Laserprint Hull Ltd. in England, as well as "Laser Mark" equipment from Lumonics, Inc. (Ottowa, Canada) Codes with smudged or missing numbers or letters usually constitute a major defect and sometimes a critical defect, depending upon product category and marketer attitude. For this reason the operation of a coder should be checked frequently. If a problem is encountered all cans produced with a defective code will probably have to be segregated for rework. All coders have practical limits in terms of the number of lines (usually two) and characters per line. The limits must be considered during product development or in the quoting process. Can Counters Starwheel actuated devices are available at very low prices for counting cans passing any point on the aerosol line. Differences between two or more of these counters provide information relating to can losses during production. Powder Filler This type of filler is needed for the addition of talc, silicas, bentonite clays, dry starch derivatives and other finely divided solid materials to aerosol cans. In some instances limited amounts of these materials may be added alternately as a slurry, provided sufficient carrier is used that the slurry is not too stiff. Up to 16% aluminum chlorhydrate is added to antiperspirant cans in the form of a slurry, but in most cases the amount of powder that can be added is less than 6%. Direct addition of powders provides an alternate approach, and is frequently the only way to add relatively large amounts of powder, particularly if the amount of solvent carrier is very limited. Thus the addition of individual or blended powders to aerosol cans provides better formulation flexibility and may solve other handling and mixing problems as well. The Diehl-Mateer line of powder fillers by the Mateer-Burt Co. are quite popular, especially for lower speed lines. They are available in both in-line and rotary models. Up to four in-line units have been mounted on aerosol lines, depending upon indexing and trackage. The Model 10A powder filler design is of interest in that it incorporates an electronic volume control feature. A solid state digital counter scans the auger shaft revolutions to provide improved accuracy. The system is available as a kit to improve fillers made before about 1968.
Aerosol Production Equipment 391 A second line of powder fillers is the CMR series: a series of higher speed rotary machines capable of virtually dust-free operation at up to 450 cpm. Most of these fillers incorporate the Perry Accofil system for greater filling accuracy. The machines are produced by Perry Industries, Inc. In a few instances powders must be filled into non- metallic containers, and here static charges can be a serious impediment to obtaining a clean, accurate fill. Herbert Products, Inc., the 3M Company and other firms have deionizing equipment that can effectively eliminate this difficulty. Liquid Concentrate Fillers The selection of the concentrate filler may involve one of die most difficult and cost-intensive decisions a packager must make during equipment selection. A series of compromises must be made in relation to price, job requirements, maintenance and other factors. Some of the general types are: a. Vacuum or vacuum-gravity — constant level — liquid. b. Piston — volumetric — liquid, semi-viscous. c. Pressure-time — liquid, semi-viscous. d. Pocket filler — volumetric gravity — liquid. e. Time-gravity — liquid. The first consideration is die type of concentrates which must be handled. For the contract filler this will normally mean a wide variety of liquids, ranging from low viscosity to barely pourable types. Filling weights may vary between 6 and 600 grams, and diis particular variation is generally best handled by the use of change- parts; e.g. different orifices or different cylinder sizes. The captive filler may use his machine for die filling of only one or two products, in which case the buying decision is much easier. Other considerations may be summarized as follows: a. Time required for mechanical changeover from one can diameter to another or from one height to anodier. b. Cleanability of the machine. Time required to break down and dioroughly clean all contact parts such as filler bowl, filling nozzles, pistons, cylinders, valves and so forth. c. Maintenance accessibility. Access to die motor, gear reducer and drive train is very important in case of breakdown as well as for regular maintenance. d. Maintenance level. Consider die degree of protection given to the motor, power train and other moving parts so diat concentrate spills and flush liquids will not come into contact widi diem and reduce their operational life. Maintenance often increases as die number of elastomeric seals increases. The seals must be made of materials compatible with die concentrates. e. Ability of the machine to function reliably without the need for a machine operator. This saves on labor but may increase maintenance requirements. f. Cost. A good high speed filler will cost from $20,000 to $80,000 if purchased new. A used filler has a much lower initial cost, but maintenance costs will be much higher, and production losses due to breakdowns more frequent. Older machines tend to leak and have less accuracy. A very large number of equipment manufacturers offer concentrate fillers. Each has unique advantages and disadvantages. It has been said that die experienced maintenance man or filler operator can detect a "personality" in every filler, and that even supposedly identical fillers will respond quite differendy to various production situations. By developing a rapport with filler idiosyncrasies die maintenance man can predict problems, lay in stores of change parts known to have short service livfes, and make adjustments that will enable the machine to give maximum performance. Typical fillers are listed as follows: a. The "JG Volumetric Product Filler" (also designated as the "Model VOF-A Automatic Volumetric Filler" when mounted with conveyor system) is available from die JG Machine Works, Inc. (Patterson, NJ) The Model VOF-A has a reported accuracy of ±0.25% which makes it very interesting. Interchangeable product fill cylinders are available in 30 to 550 cc. capacities. The Model VOF-A provides speeds up to 65 cpm. depending on fill and viscosity. b. "Cozzoli Filler", by the Cozzoli Machine Company (Plainfield, NJ) The 8-head model does about 50,000 units per shift under average fill conditions and the 16-head can do almost 100,000 units per shift on a similar basis. Highly versatile, Next Page
Aerosol Production Equipment Previous Page A second line of powder fillers is the CMR series: a series of higher speed rotary machines capable of virtually dust-free operation at up to 450 cpm. Most of these fillers incorporate the Perry Accofil system for greater filling accuracy. The machines are produced by Perry Industries, Inc. In a few instances powders must be filled into non- metallic containers, and here static charges can be a serious impediment to obtaining a clean, accurate fill. Herbert Products, Inc., the 3M Company and other firms have deionizing equipment that can effectively eliminate this difficulty. Liquid Concentrate Fillers The selection of the concentrate filler may involve one of the most difficult and cost-intensive decisions a packager must make during equipment selection. A series of compromises must be made in relation to price, job requirements, maintenance and other factors. Some of the general types are: a. Vacuum or vacuum-gravity — constant level — liquid. b. Piston — volumetric — liquid, semi-viscous. c. Pressure-time — liquid, semi-viscous. d. Pocket filler — volumetric gravity — liquid. e. Time-gravity — liquid. The first consideration is die type of concentrates which must be handled. For the contract filler this will normally mean a wide variety of liquids, ranging from low viscosity to barely pourable types. Filling weights may vary between 6 and 600 grams, and this particular variation is generally best handled by the use of change- parts; e.g. different orifices or different cylinder sizes. The captive filler may use his machine for die filling of only one or two products, in which case the buying decision is much easier. Other considerations may be summarized as follows: a. Time required for mechanical changeover from one can diameter to another or from one height to anodier. b. Cleanability of the machine. Time required to break down and dioroughly clean all contact parts such as filler bowl, filling nozzles, pistons, cylinders, valves and so forth. c. Maintenance accessibility. Access to die motor, gear reducer and drive train is very important in 391 case of breakdown as well as for regular maintenance. d. Maintenance level. Consider die degree of protection given to the motor, power train and other moving parts so diat concentrate spills and flush liquids will not come into contact widi diem and reduce their operational life. Maintenance often increases as die number of elastomeric seals increases. The seals must be made of materials compatible with die concentrates. e. Ability of the machine to function reliably without the need for a machine operator. This saves on labor but may increase maintenance requirements. f. Cost. A good high speed filler will cost from $20,000 to $80,000 if purchased new. A used filler has a much lower initial cost, but maintenance costs will be much higher, and production losses due to breakdowns more frequent. Older machines tend to leak and have less accuracy. A very large number of equipment manufacturers offer concentrate fillers. Each has unique advantages and disadvantages. It has been said that die experienced maintenance man or filler operator can detect a "personality" in every filler, and that even supposedly identical fillers will respond quite differendy to various production situations. By developing a rapport with filler idiosyncrasies die maintenance man can predict problems, lay in stores of change parts known to have short service livfes, and make adjustments that will enable the machine to give maximum performance. Typical fillers are listed as follows: a. The "JG Volumetric Product Filler" (also designated as the "Model VOF-A Automatic Volumetric Filler" when mounted with conveyor system) is available from die JG Machine Works, Inc. (Patterson, NJ) The Model VOF-A has a reported accuracy of ±0.25% which makes it very interesting. Interchangeable product fill cylinders are available in 30 to 550 cc. capacities. The Model VOF-A provides speeds up to 65 cpm. depending on fill and viscosity. b. "Cozzoli Filler", by the Cozzoli Machine Company (Plainfield, NJ) The 8-head model does about 50,000 units per shift under average fill conditions and the 16-head can do almost 100,000 units per shift on a similar basis. Highly versatile,
392 The Aerosol Handbook with product cylinders from 20 cc. to 600 cc. The 20 cc. size provides tolerances of better than ±0.1 gram, even with slurries. The 16-head can also fill two concentrates, one in each 8-head in-line section, or the same concentrate twice, if an especially large volume fill is needed. Filler speeds are decreased to about 50% under these conditions. c. The Filler Machine Co. (Philadelphia, PA) supplies versatile piston fillers in rotary, multi-in-line and single in-line models. Their 8-head rotary operates from 120 to 200 cpm, depending upon fill conditions. d. The National Instrument Company (Baltimore, MD) manufactures alarge line of "Filamatic" inline and rotary piston fillers which are versatile, very accurate and fairly inexpensive. While many Figure 18. Food Aerosol Machine Nalbach Model 16-RS r I I 1J I1 I"'../ *»'X I. M t I ! ■« <A models have limited speeds, the larger in-lines and their Model 400R 16-station rotary can handle the needs of any high speed aerosol filling operation. A wide variety of accessories are available, such as pumping units to push high viscosity products fully into the piston filling cylinders, final filters that locate between the discharge valve and filling nozzle to "polish" concentrates immediately prior to filling, and heaters for handling gel-type and similar products that must be filled in the 150°-200°F (66°-93°C) range. e. The U.S. Bottlers Machinery Co. produces a line of rotary vacuum fillers which are excellent for water-based aerosol concentrates. The 36 head unit will handle the largest aerosol fills at speeds of 280 cpm. f. '' Levelmatic Filler'', by the New Jersey Machine Co. High speed, uses a unique fluidic sensor to control liquid level in the can, eliminating need for an overflow system and speeding up cleanup and changeovers. g. The New Way Packaging Machinery Inc. firm (Hanover, PA) produces an extensive line of product fillers and accessories. Their Model 700 Automatic Rotary Liquid Filler can be used for filling medium to larger size aerosols, and actually other containers up to about one-gallon (3.785 liters) in size for "duplex" (aerosol and non- aerosol) production line requirements. The 24-head filler can run to 200 cpm in the case of foaming or non-foaming products and will fill fairly viscous items, but more slowly. A smaller product filler, the 12-head Model A31, will do up to 72 cpm with fills ranging from 10 g to several liters. h. In England a number of advanced-design fillers are available from such firms as the Neumo Division, P&L Industries Ltd. (England); C.E. King, their "Technfill" machines with a dial-a-dose volumetric control to below ± 0.5%, starting at 1 ml fills; DH Industries Ltd., where mini-fillers are available to handle inhaler aerosol slurries, for instance, and use a recirculating system with an air-operated filling nozzle on the end of a slave cylinder; and Adelphi Manufacturing Ltd., whose new Mark V Accramatic electronic filler will handle from 1 to 700 ml fills at low to
Aerosol Production Equipment 393 moderate speeds. A single length of tubing acts to both draw and dispense liquids. Additional firms that supply product fillers include: a. The Kartridg Pak Co. (Model 124 rotary, 24 head, ±0.5 ml.) b. Cherry-Burrell Corp. c. MRM/Elgin Packaging Machinery Corp. d. Terco Inc. e. Pneumatic Scale Corp., Ltd. f. Pacific Packaging Machinery Co. g. John R. Nalbach Engineering Co., Inc. h. Hercules Inc. Several of these firms provide integrated fillers and crimpers, or filler/crimpers/gassers. The Nalbach Model 16-RS Food Aerosol Machine, illustrated in Figure 18, includes twin sanitary product fillers, automatic valve sorting, a valve crimper and coder in one compact unit. It will handle about 30 cpm, or 25,000 units per day on a two shift basis. In the Terco Indexing Rotary Filling Machine, rated at 100 cpm and illustrated in Figure 19, the product fillers are only one small component of the overall integrated assembly. Such lines often contain propellent charging equipment. In this case close-coupling of the gassers may fail to consider the need for separate gas houses for hydrocarbon injection. The Terco Inc. 40 cpm rotary equipment shown in Figure 20 is completely air operated and, for hydrocarbon gassing operations, is designed to be located in a gas house. All stations are interlocked, so that the slowest controls the line speed. It also has a no-container no fill-feature. Situated around the three foot (914 mm) plastic disc are a can cleaner, coder, twin fillers, a purger, crimper and two propellent chargers. Various accessories are often added to concentrate fillers, some more necessary than others. For example, one company has developed various types of continuous sonic defoaming systems for reducing problems often encountered with rug cleaner concentrates, bathroom cleaner concentrates and other high-foaming liquids. The Herman H. Sticht Co. (New York) has their Standco Model 450 and other dial gauges for continuously monitoring the production rate of fillers as a function of die revolutionary speed and number of heads. Some fillers have built-in screens or filtration systems, but in most cases a final filter is placed on die ho* mwj hoi*** *hi in** haihwi •ar* Figure 19. Rotary Filling Machine 100 CPM Indexing rotary filling machine by Terco, Inc. incoming product line, just before the filler. The larger fillers are very complex machines, with over a thousand individual parts, and it is necessary to maintain a suitable supply of replacement items: springs, gaskets, adapters, sealing rings and so forth. It is a good idea to permanendy number the individual filling heads of both in-line and rotary fillers, using solvent-resistant colored tape made for such purposes. The filling of glass aerosols requires specialized equipment, as illustrated in Figure 21. Here a Nalbach Figure 20. Rotary Filling Machine 40 CPM Unit with cleaner, coder, fillers, purger, crimper and gassers. Made by Terco, Inc. -i Tl J >t . V Jl K r i »$ V 4 K
394 The Aerosol Handbook Glass Aerosol Filler and Crimper is used for the slow- speed rotary filling of various glass, plastic-coated glass and 20 mm type aluminum tubes (in pucks, if they are very slim), with either hand or.conveyorized container entry. Checkweighers These small machines became important during the early 1960s as a permanent quality control feature of larger aerosol lines. A typical unit is the "Metramatic" Model 121806, by the Metramatic Corp. Most highspeed lines have one of these checkers, usually situated right after the gassers and often in the gassing house. But some also have a checker located after the filler as well. It basically comes down to a matter of dedication to quality and available funds. Because the checkweighers can only determine the gross weight, and since the weight of the empty metal cans will often vary up to about ±8% (generally within ±5 g, however) die checkweigher readings will not replace production control and quality control weight Figure 21. Tube and Glass Aerosol Filler and Crimper by John R. Nalbach Engineering Company [ \ . u % validation routines. The checkweigher may be set to reject units weighing outside ± 6 g of the target weight, since on the basis of taking the square root of die sum of the square of can variation and the square of fill variation, mis would allow for a can variance of ± 5 g and a fill variation of ± 3.3 g. Cans rejected by the air blast or air-operated ram at the end of die checkweigher move into a small collection area and are normally rechecked by hand on a small balance. Overweight cans are often sprayed down to the desired range. Underweight cans may be "short-shotted" with a few grams of additional propellent. Both practices are being increasingly frowned upon by highly quality conscious marketers, however, and may be used to a lesser extent in the future than now. The prevailing opinion is that an off- weight can is out of specification because of under- or over-filling of eidier the concentrate or the propellent; not bodi. The balance between the two is dierefore upset and die can does not contain die stipulated percentages of each. The "whitewashing" type corrections just mentioned do nodiing to rectify the underlying problem, except fortuitously in the case of short- shotting. Checkweighers are readily available that are rated for 200 to 300 cpm. When one is used at speeds faster than the nameplate rating it will tend to kick out more correct weight cans than die normal 0.1% or so. Checkweighers for very small aerosols often have lower speed ratings of 40 to 80 cpm. Microprocessor controls automatically compute various statistics. Valve Inserters Both in-line and rotary models of these large machines are available from a number of suppliers. When purchasing one of diem certain considerations should be given to attributes such as: a. Changeover time, for the range of cans to be run on that line. b. Change parts which will be needed. c. Delivery schedules — sometimes very long. d. Maintenance accessibility e. Can handling capabilities. The sorting abilities of most valve inserters are about the same. Special problems may arise when attempting to sort aluminum valves, stainless steel valves, valves without diptubes or valves with extra-large diameter diptubes. In some instances, a so-called "dummy dip-
Aerosol Production Equipment 395 tube" can be applied to valves designed for inverted actuation, thus facilitating can handling. Various sensing devices improve quality control aspects of this operation. For instance, a mechanism using either a micro switch or electric eye may be used to reject valves with no diptubes as they pass along the slot conveyor toward the inserter station. Valve inserters are quite large. The PMC Industries, Inc. Model VP2 and CR-1200 inserters consist of a valve bin, a separate sorter connected to the bin by means of a magnetic escalator belt, and the rotary inserter unit, connected to the sorter by the slot conveyor. The units may be arranged linearly or in an angular fashion, depending on space allocations. The linear length can easily exceed 18 feet. If all units are floor-mounted, the ceiling height should be 10 feet or more, but it has now become fashionable to place the sorter and bin sections on a mezzanine and lead the slot conveyor to the inserter through a rectangular hole in the deck. This arrangement is desirable in that it also provides for valve storage, case knockdown and stacking, and generally affords better raw material access than is available through the congested production area. Perhaps the smallest inserter is Nalbach's Model VS Sorter plus Model VP Inserter, capable of 35 cpm. The in-line Kartridg Pak machine operates between 50 and 360 cpm and costs about $60,000. It is illustrated in Figure 22. Inserter mechanisms may differ in small but significant ways. When the Precision Valve Corp. PE-sleeve innovation was first production-tested in the U.S.A. at the end of 1981 it was found that the PMC inserter would not work with the new, smaller mounting cup, without one very minor change. The inside wall diameter of the four available PE-sleeve cup variables is 0.944" ± 0.003 " (24.00 ± 0.07 mm) instead of the usual 0.969 "±0.003" (24.61 ±0.07 mm) — like the PVC nylon (Zytel 101) clad valve cups which are 0.963 " ± 0.003" (23.80 ±0.07 mm). In the PMC inserter a double-split nylon tube is used to spring-fit very snugly into the mounting cup, so that the valve can be lifted and then inserted into a waiting aerosol can. The tube has a diameter of about 0.980" +0.002 " (24.89 ±0.05 mm) and it could not bend inward sufficiently to fit within the smaller PE-sleeve valve cups. By making four additional slits in the tube (or a total of eight) a workable tube is possible, but a better method is simply to machine an existing one to about 0.955 " ± 0.002 " (24.26 ±0.05 mm) and use it only for PE-sleeve or nylon clad PVC valve cups. Valve Crimper In the case of one-inch (25.4 mm) cans the valve crimper may be a separate in-line or rotary machine, a functional station in an in-line or rotary device that performs several operations, or a functional phase in a complex machine such as a Kartridg Pak U-t-C gasser. Where 13 mm or 20 mm ferrules are involved, die operation is done either separately or as one operation of an in-line or rotary multiplex device, such as that illustrated in Figure 21. Although die area of terminology is somewhat blurred by misuse, "crimping" is normally thought of as die outward spreading of collet segments or jaws to make an hermetic seal. The operation is commonly called "swaging" in the United Kingdom. On die odier hand, "clinching" is a term reserved for die inward compression of valve ferrules by means of collet tines, to make an air-tight seal. "Roller-clinching" has been used to describe a process where several flat wheels converge inwardly on a ferrule or (less commonly) a one-inch (25.4 mm) valve cup to seal them on various containers. In die new PET (polyemylene terphdialate) plastic botdes, developed in Europe in 1980, and cur- rendy under development in much larger sizes in die U.S.A., it appears that roller-clinching is the preferred method of closure. Before diis die only time one-inch (25.4 mm) valve cups were clinched or roller-clinched was in the case of die old Risdon Model JBR "turret- type" valve of the 1950s. Valves may be either atmospherically crimped or vacuum crimped. Vacuum crimpers of both in-line and Figure 22. Automatic Valve Sorter and Inserter by The Kartridg Pak Co.
396 The Aerosol Handbook rotary formats were introduced about 1957, but they did not become popular until the 1960s. At that time many CFC type products were cold-filled and propellent vaporization very effectively removed the tramp air from the head space. For pressure loaded products air could be removed by means of CFC gas jets and drips, or by means of CO2 gas streams. (CO2 was then priced at only about $0.03/lb. ($0.066/kg) in bulk, at least in many parts of the country.) The early rotary vacuum crimpers were able to draw up to a 25" Hg° (-84.7 kPa) vacuum in cans having head spaces of about 150 ml or less, which is about 83.6% of a full vacuum and rather phenominal by today's standards that normally range from about 16 to 21" (-54.2 to -70.9 kPa) for K-P Under-the-Cap machines and other composite equipment. Drawing partial vacuums on cans is somewhat useful in minimizing full-can pressures and in slowing the effects of some forms of corrosion, but in general the advantages of vacuum crimping are overstated. A single-head one-inch (25.4 mm) valve crimper is nominally rated at about 60 cpm, but they have been driven to 75 or 80 cpm on some lines by the application of modest engineering changes. When these same heads are used for vacuum crimping, the rate often falls as the evacuation level increases. An indication of the amount of air withdrawal necessary to achieve certain vacuum levels is shown in Figure 23. VOLUMES OF AIR WITHDRAWN (Each volume is equal to the size of one headspace.) Figure 23. Theoretical and Typical Can Evacuations The single-head units made by Nalbach, such as Models 1-HVC and 1-HCRP, can use either the outward crimping collet for one-inch (25.4 mm) valves or the inward clinching collet for ferrule type closures. Large machines are available from this supplier. Their Model 4-HVC consists of four heads in a rotary frame and can handle from 50 to 150 cpm, depending upon head space size and the degree of can evacuation reqired. A still larger unit with eight heads runs at rates of 80 to 240 cpm on the same basis. The J.G. Machine Works, Inc. produces a line of quality standard, vacuum and ferrule type crimpers of the one-head design, rated at up to 60 cpm. Crimpers are also sold by The Kartridg-Pak Co., Terco Inc. and other suppliers. Ferrule crimping is done by changing over standard crimpers with standard change parts, or by using regular ferrule clinchers. Clinching is often considered to be a more demanding operation than crimping, since there are several bottle finish diameters (and thus ferrule diameters) and several depths according to the container profiles. Different settings are required for plain glass, plastic coated glass, various types of aluminum tubes and straight plastic aerosol containers. At least five top finish designs are used for aluminum tubes. As an added complexity, the Rudy Lechner barrier pressure packs (distributed by On-Line Equipment subsidiary of John Lelliot Ltd. in the U.K., Ireland and the Middle East, and by Aerosol Services, A.G., Switzerland, in the rest of the free world) use an internal aluminum tube or pouch with a flange and thin cut gasket that fits between the monobloc aluminum can curl and the valve. The ferrule clinching height must be adjusted downward to allow for the inserted flange and gasket. The Lechner system is also available for one- inch (25.4 mm) cans, and the same considerations apply. A bottle crimping collet is much larger than the collet for cans having a one-inch (25.4 mm) plug, and several times more expensive. The adjustment of clinching depth is made by adding or removing shims from under the valve sealer. The shims are generally from 0.005 " to 0.010" (0.127 to 0.254 mm) thick and are made of hardened steel. The distance between the valve sealer and collet jaws governs the tightness of the clinch. For a plain glass bottle with a typical 0.209 " ferrule skirt, the distance from the bottom of the valve sealer to the bottom of the collet is about 0.235 " (5.97 mm). The same setting is used for plastic coated glass containers, where the skirt length may extend to 0.335" (8.51 mm) in
Aerosol Production Equipment 397 order to bind the plastic to the glass more effectively. The Kartridg Pak Co. supply their Model 919 for slower speed operations, plus a variety of machines for speeds running to 120 cpm, and even higher. Similar equipment is available from several other suppliers. Propellent Gassers Pressure chargers can be classified into two main categories: those that fill through die crimped or clinched on valve and those that fill around crimped on valves. The first is sometimes called a T-t-V (Through- the-Valve) type and includes bodi the liquid injection machines and die gasser-shaker for gaseous gases. The second is generally called the U-t-C (Under-die-Cap), from terminology suggested by the supplier: The Kartridg Pak Co., who like to call a cup a cap. T-t-V liquid injection chargers act to force liquefied propellents dirough the valve under pressures that are typically in die range of 650 to 1,100 psig (4.48 to 7.58 MPa) but most often in die middle half of that pressure span. The injection pressures are derived eidier from an air-powered booster cylinder assembly or liquistatically operated booster pumps, such as Union or Wheadey types. A very large number of valves are designed specially to accept propellent at rates of 300 ml/sec. They are called pressure filling or PF valves. One very effective design by Precision Valve Corp. is known as die "splined cup and hex-gasket" valve. The availability of all these valves has rather effectively reduced the gassing speed barrier that used to be a fair-sized problem for die T-t-V fillers. A very low speed, very simplistic filling, crimping and gassing operation is shown in Figure 24. Even on diis small scale it would be considered inappropriate to gas products widiin anything odier than a separated explosion-proof structure with high ventilation, propellent sensing and all the odier features that make up what is commonly called a gas house. For any installation much larger dian diis, die propellent must logically be transported to the filling location in eidier tank cars or tank trucks and be stored in above-ground bulk tanks. Many of the larger fillers have one or two dozen such tanks, ranging in size from 1000 to 30,000 gallons (3785 to 113,600 liters) in nominal capacity. (Actual overflow capacities are about 8% larger.) Figure 25 is a panoramic view of a very sophisticated propellent storage system for chloro- fluorocarbon and hydrocarbon propellents now in use by the Samuel Taylor (Pty.) Ltd. Division near Sydney, Australia. A full description of the engineering and safety requirements for propellent storage installations can be obtained from any of die propellent suppliers (see Aerosol Propellents chapter) and would be too lengdiy to discuss here. In brief, the propellent is withdrawn from die bulk tank or blending facility and pumped through a welded piping system containing excess flow check valves, excess pressure relief valves, screen filtering equipment, an accumulator and odier devices, finally entering the gas house. This structure should consist of a small room, preferably set completely outside the main building and outfitted with explosion- proof equipment (Group 1, Class D for hydrocarbons or Group 1, Class C for dimediyl ether). A typical gas house is shown in Figure 26. Cans are brought in dirough die 8 "(203 mm) wide aperture at the left, using a hooded conveyor to protect them from rain if they are not already crimped. They are T-t-V or U-t-C gassed in the upper right-hand quadrant of the gas house and then returned through die 8" (203 mm) opening at die right. Experts are strongly divided about die wisdom of including odier devices in the gas houses, but in diis sketch, space is allocated at die left for die installation of a high-pressure propellent pump and vacuum pump needed for U-t-C operations. The building itself is ideally constructed from reinforced 6 " to 8 " (152 to 203 mm) concrete (or from concrete block as an alternate), except for one wall Figure 24. Terco Inc. Hand Operated Filling Machine with Production Heads Shown at left, front: explosion proof vacuum pump; left rear, mechanical charging valve; center, vacuum sensing valve and propellent handling system; right, product nozzle, product tank.
398 The Aerosol Handbook fitted with blow-out panels held in place with shear-pin fittings. The 2 '0 " (610 mm) opening provides the fresh air inlet for the ventilation system. Ideally, air is swept across the floor and drawn up into registers just under the blow-out sections. From there it rises through a duct terminating about 10 -0 " (3.05 m) above the gas house roof. The gas house should also be outfitted with hydrocarbon gas detection systems (which will also detect dimethyl ether, if that propellent is to be used). This equipment typically uses infrared spectroscopy and microcomputer-controlled components to detect propellent gases and provides read-outs and response modes in terms of percentage LEL (lower explosive limit). Instrument capabilities range from portable, single purpose analyzers, such as the Sierra Monitor Model 2000 Portable Combustible Gas Leak Detector by the Sierra Monitor Corp., (Sunnyvale, CA), which is sensitive to 25 ppm, but not recommended except for small installations and back-up purposes) to the large, permanently installed equipment by such firms as the Mine Safety Appliances Co., the Foxboro Analytical Division (Norwalk, CT) and the Fenwal Corp. (Chicago). These instruments provide audible, visual and/or electrical interlock alarm operational modes, including complete shut-down of the propellent supply and production facility if the gas concentration becomes too high, typically 50v% of the LEL concentration. A large number of small, single head aerosol pro- m — U'-4" i i Blow-^ut panels ■rei T Smooth concrete floor pitches toward drain, 1" per lO'-O". -*- 2'-0" -*4*- 2'-0" -*-j 64*-*|l'-Oj ■« "IS V A"* I *CANS door I 2 &' i i j i » ij *cfNs I fcANS ' ' R" ' _x Figure 26. Floor Plan of Gashouse pellent chargers are available, such as the Nalbach Model HPC pneumatic type illustrated in Figure 27. Figure 25. Propellent Tank Farm Chlorof luorocarbon and hydrocarbon tank farm. Samuel Taylor Division, (Pty.) Ltd. Sydney, Australia. Illustration shows 22-bulk tanks Imperfections in the photograph are due to compositing three views, and protective sprinkler system with heat deflectors over most indicated by the thin separation lines in the picture. sprinkler heads. New 30,000 gallon (114,000 liter) storage system is in construction at right. (i * * jr i it '1 i . * "—mv ■ 1' • r ,K- /.r \ _ > j "^ 4 7
Aerosol Production Equipment 399 This particular unit can be supplied with measuring and charging cylinders from the 5 to 50 ml range to the 30 to 300 ml range. Unless the valve is impeded, these hand-operated gassers will easily do 25 to 30 cpm. For in-line gassing operations, speeds are generally limited to 100 to 140 cpm, on the basis of a double- indexing, double row production facility using four chargers. But for speeds of over about 75 cpm the option of going to a rotary gassing system should be considered very seriously. Some rotary systems, such as those by Terco, Nalbach, Aerofill and Coster are of the "core assembly" type mentioned previously, and as illustrated in Figure 10. But for high-speed production lines, it is best to consider the gasser as a separate functional unit. Several rotary gassers are available. Through-the- Valve (T-t-V) types are made by Kartridg Pak, Coster, Pamasol and other firms. They appear to be more popular in die U.S.A. than in eitiier Europe or Japan at this time. The Coster Technologie Speciali s.p.a. (Italy) RTV-128 rotary is a high speed machine sold and serviced by AyPak Machinery, Inc. (Closter, NJ). By far the most popular T-t-V type rotary gasser in the U.S.A. is the Kartridg Pak "small base" line of machines. They are rated at 25 cpm/head (max.) for Model 70 fixed can handling and at 18 cpm/head (max) for Dial-O-Matic can handling, and are available in models carrying 3, 6, 12 and 15 heads. The production rate is determined from the expression: For example, for a 240 ml propellent fill and a valve diat gases at a rate of 80 ml/sec, a 12-head machine will provide 156 cpm. (This figure is validated by noting that it is under the maxima of either 300 or 216 cpm, depending on die method of can handling used.) These machines are outfitted widi propellent cylinder liners diat provide for fills between 4 and 550 ml with a maximum accuracy of ± 0.8 ml, but optional liners can be obtained to provide filling ranges of 2 to 100 ml and 4 to 1000 ml with the same accuracy. (The earlier 1 to 35 ml liner has been discontinued.) Propellent is normally supplied to die machine pre- warmed to about 100°F (37.8°C) and at a pressure of from 400 to 1000 psig (2.76 to 6.90 MPa). The warming step is useful as a means of reducing die liquid density by 5 to 10% and thus reducing die weight of propellent lost to the gas house atmosphere each time the machine releases a can at die end of the cycle. But it is also important in keeping the various Disogrin, Buna N, Neoprene and Viton gaskets warm and supple, and at their ideal dimensions. (Here it is again noted that Viton and other standard gaskets may be incompatible with dimethyl edier, DME, and they should be checked carefully in diis high-solvency propellent, prior to any productions.) The propellent pressure can be regulated by turning the square-headed screw on top of die line regulator. Below 400 psig (2.76 MPa) there is not sufficient pressure to motivate rapidly key components in the machine. At over 1000 psig (6.90 MPa) machine wear is increased. As a general rule the machines should be run at about die lowest pressure diat will satisfy production rate requirements. Many fillers make die mistake of operating in the 1000 to 1200 psig (6.90 to 8.27 MPa) range, using only a small portion of the machine's filling cycle. This is a poindess exercise and increases wear on the moving parts. Measured with a meter or special balloon at any one time, these gassers will almost always show a certain amount of normal propellent leakage. The leakage rate is a lot less at 600 psig (4.14 MPa) than it would be at 1200 psig (8.27 MPa). The Kartridg Pak "large base" T-t-V gasser is an 18-head machine required only for the very highest speed operations. Under ideal conditions it can easily achieve speeds in excess of 400 cpm. It is a massive s t Figure 27. Nalbach Propellent Charger Production Rate - Valve Filling Rate (ml/sec) x fi0 >w.yTT1,n y Number of Heads 1.54 Propellent Volume (ml/can)
400 The Aerosol Handbook device, costing over $100,000 and having many constructional and operational differences when compared to the "small base" gassers. Only a limited number have been sold to date. Perhaps the most commercially successful of all gassers is die Kartridg Pak U-t-C 9-head unit. This machine actually performs three individual functions: air evacuation, propellent filling (around die slightly lifted valve cup) and crimping,, as the can revolves within it at speeds of from 3.3 to 27.0 rpm. Figure 28 illustrates the planetary sequences. In terms of accuracy and reliability it is not a highly effective machine. For instance, the accuracy is listed as ± 2.0 ml maximum, and a number of firms have a program for "beefing up" new U-t-C's when diey come in. On die odier hand, the high-speed capabilities, flexibility and tripartite operational mode have won wide acclaim, especially in the U.S.A. From a minimum fill of 4 ml, diree charging cylinder liners provide maximum fills of 100 ml (optional), 550 ml (standard) or 1000 ml (optional). The last size, for instance, would be used only for aerosols of a quart (946 ml) or more in size, and where a major proportion of the fill was propellent. Many aerosol people feel that the 9-head U-t-C will operate at up to 20 cpm per head, but this is only an estimate. The method of can handling, fill size and degree of evacuation versus container head space volume are all important factors. With fixed can handling (Model 70) the 9-head machine will fill up to 180 ml per can at rates up to 25 cpm per head, provided evacuation is not a speed deterrant. This size fill equates to about 100 g for the hydrocarbons and to over 240 g for the chlorofluorocarbons, which is more than most filling specifications. But where fills larger than 180 ml are needed, the maximum rate can be calculated as 4500/fill in ml/head. For example, a 300 ml fill can be delivered at up to 135 cpm for a 9-head machine. Considering die range up to 180 ml of fill volume, it follows that a 9-head machine should operate up to 225 cpm, if there is fixed can handling and no can evacuation drawback. In practice, many machines have been re-engineered (different sprockets, etc.) to provide maximum rates in die 285 cpm area. Additional wear has to be accommodated by maintenance programming, but this is a modest price to pay for increasing production from 94,500 to 120,000 units in a typical eight-hour (actually 420 min) shift. For Dial-O-Matic in-feeds the 9-head U-t-C will produce up to 18 cpm/head at fill volumes up to 250 ml. Above this the equation 4500/fill in ml will give the rate. The U-t-C will draw 20 " Hg° (68 kPa) of vacuum in an empty 500 ml can at 18 cpm/head rates, using a 5HP vacuum pump capable of about a 29 " Hg° (98 kPa) tank vacuum under no-load conditions. For higher vacuums the speed of die machine must be reduced. It is important to note mat the actual vacuum drawn upon the can is not the amount shown by the vacuum gauge on the machine. There is always some loss, in the area of 10 to 15% if good maintenance is observed. To check actual can evacuation levels, the machine must be run under normal "on the fly" equilibrium conditions, but with die propellent flow cut off from one or more heads by merely moving die lever arm of die Jamesbury or odier valve at the head. Because of the cost in underfilled cans mis quality assurance check is made no more frequently than necessary. If the associated pumps and drive are considered, die power requirement for a 9-head U-t-C will be 15 HP for a supply of 15 gpm (56.8 liters/min) using a Triplex pump, or 13 gpm (49.2 liters/min) using a Duplex propellent pump, under maximum operational conditions. The machine is used occasionally with 3 or 6 heads on die 9-head frame; and in these cases the power requirement is substantially less although the rating is generally the same. The U-t-C is an extremely complex instrument. Many options are possible. There are pre-set and pre- FRONT OF MACHINE Figure 28. Can Evacuation, Filling, Crimping Sequential Operations of a Kartridg Pak U-t-C Gasser with Nine- Head Frame
Aerosol Production Equipment 401 open types, molded cap seal and "0"-ring cap seal types, and at least a dozen other variations to handle various propellent types, regular and bottom-filling cans, and so forth. There are certain hazards connected with the U-t-C, as there are with most complex machines. In one case, a typical machine was operated under conditions where the valve cup was able to be sucked up against the cap seal, thus shutting off most of the vacuum, so far as the aerosol can was concerned. Had the condition been noticed, the maintenance response would have been to turn down the collet pre-set adjustment (to expand the collet in its relaxed state) to the point where a slight drag is felt against the cup. The cup could not then be sucked up to shut off the vacuum. If the lower vacuum seal or the cap seal leaks, the result will be the same: a blow-by will occur and propellent will be drawn into the vacuum hose, where it will evaporate instantly and soon cause hose frosting. In an extreme situation, a large amount of propellent entered the vacuum hose, being drawn into the vacuum pump tank and then compressed out of that tank and into the plant area a good distance from the gassing enclosure. Eventually, the consequences were disastrous. The machine may be operated in either a right hand or left hand direction, but cannot be converted from one to the other without great difficulty. Can handling is from conveyor to a cast worm screw, and then into either a "fixed can handling" center in-feed and fixed starwheel or a "Dial-O-Matic" center guide and "Dial-O-Matic" starwheel. The "Dial-O-Matic" feature allows for the almost instant conversion of the &■ I f r i ■<& ■JZJ — T ©Ob . fi A * © •• • °0 oO • » SOLUBLE IAS SUPPLY PRODUCT UNOEKCAP PROPELLENT SOLUBLE IA3-PMOUCT FILUM* STATION PUMP IMPftESNATOR Figure 29. U-t-C and Saturation Unit Layout Typical Kartridg Pak design U-t-C from one can diameter to another, but the speed of the machine suffers somewhat as a consequence. Exiting is by starwheel, which places finished cans on a single-track conveyor. It is at this point that cans are occasionally gouged and perforated, so that powder- containing aerosols sometimes are able to develop a sufficient static charge that the contents can be ignited when a spark leaps to a grounded surface. This is discussed in detail in the flammability chapter. Kartridg Pak also produces a one-head U-t-C, designed mainly for laboratory and small production facilities. It can be hand or conveyor fed and can do 15 to 20 cpm. Larger laboratories often use them to simulate large-scale production equipment. The technique of U-t-C "instantaneous impact gassing" was developed by Paul D. Hughett about 1970, using such a machine at the Peterson/Puritan, Inc. research center in Danville, IL. Before this development, carbon dioxide (CO2) and nitrous oxide (N2O) were introduced into aerosol cans either with a LeMay, Andora, Nalbach or other type of gasser-shaker; or at faster speeds by means of a Kartridg Pak U-t-C system equipped with a "saturator tower". This tower, sometimes called a "soluble gas product impregnator", was used to pre-agitate approximately 40 to 60% of the product with a fixed pressure of propellent gas. Ungassed product entered in one part of the tank and was sent through a baffle system and mixing area, so that it dissolved 88 to 94% of the equilibrium amount of propellent for that pressure and temperature. The gassed product then left the saturator and was fed to the U-t-C as if it were a regular propellent. By using a pressure in the 220 psig (1.52 MPa) area, the final equilibrium pressure of the aerosol would be 90 to 105 psig at 70°F (620 to 724 kPa at 21°C). This system was fairly good for very low production runs, but had a number of problems, such as the loss of all the material in the tower after each run. See the schematic drawing in Figure 29. The principle of "instantaneous impact gassing" is thought to have been first considered in West Germany, about 1968, for cans fitted with extremely high gassing rate Precision valves. It suggests that the act of blasting high pressure soluble gas into an aerosol can containing a concentrate will disrupt the liquid into something akin to a super thick mist with an enormous surface area; thus facilitating absorption of the gas before the pressure can rise to can-bursting levels of 220 to 280 psig (1.52 to 1.93 MPa), at least in the case of tinplate cans. Experimentally, it was found that when
402 The Aerosol Handbook super-fast injection pressures reached about 575 psig (3.96 MPa) the break-up action overcame the pressurizing action and the process was successful, at least where there was at least about 19v% headspace for expansion and mixing, and where the concentrate was not too viscous. The optimum pressure range is 625 to 650 psig (4.31 to 4.48 MPa). Above 650 psig (4.48 MPa) the system still works well enough, but this range may not be attainable with cool CO2, due to condensation. To our knowledge, N2O has never been gassed into cans by instantaneous impact gassing techniques, except under laboratory conditions, where it works out as well as CO2. The reason for this lies in its strongly endothermic character, and the worry about decomposition with heat generation and other sequelae. More recently, it has been shown that nitrogen (N2) can be impact gassed, which was rather a surprise because very few grams of nitrogen can be absorbed by solvents — in the area of 10% that of C02 and N20. But with very special modifications to the U-t-C this can be done, and has proven very useful for a number of nitro- sol products. The engineering particulars used in adapting U-t-C (and T-t-V) gassers to this general type of gassing operation are only partly disclosed in the two existing U.S.A. patents, and there is no reason to delve into this complex matter in these pages. The Kartridg Pak Company produces an 18-head U-t-C gasser (Model 1967-18), which could be the most complex machine an aerosol filler would ever purchase, and perhaps the most expensive. We would estimate Figure 30. Propellent Supply System to Kartridg Pak U-f-C Gasser the cost at about $140,000 depending upon choice of accessories and other factors. Few fillers require higher speeds than the 225 to 285 cpm generally afforded by the 9-head U-t-C machines. Even if they do, there is the option of dividing the production line into a'' Y'' design just ahead of the gas house and using two 9-head machines. We would estimate that only one of the massive 18-head U-t-C gassers is sold for every 40 regular 9-head U-t-C gassers. They should provide speeds of up to 450 to 560 cpm, provided the other line equipment can be up-sized accordingly. The propellent supply system to any of the Kartridg Pak T-t-V or U-t-C gassers is a fairly complex one. A typical lay-out is illustrated in Figure 30. Liquid propellent is withdrawn from the bulk tank through a double valve, strainer and then a low pressure transfer pump, where the pressure is increased to at least 15 psi (103 kPa) and preferably at least 60 psi (414 kPa) over the regular vapor pressure. The propellent then travels to the vicinity of the gasser and goes through a second strainer, then a Wheatley or other high pressure booster pump, capable of developing 1000 to 1200 psig (6.89 to 8.27 MPa) and rated at from about 10 to 25 gpm (38 to 95 liters/min) depending on gasser size. A high pressure line then passes a safety relief valve set at about 1300 psig (8.96 MPa) and splits to form a return line to the tank via a by-pass valve and a line going toward the gasser. The gasser line goes through an accumulator and filter, then a pressure gauge (0 to 1500 psig; or 0 to 10.34 MPa) and into a short length of high pressure flexible hose that leads to a Deublin right-hand or left-hand upper rotary union on top of the gasser. The vacuum line also connects into ALTERNATE .^ACCUMULATOR -* TANK " 1
Aerosol Production Equipment 403 this union. Check valves have not been mentioned, but are included. Pressure relief valves should be placed everywhere in the system where propellent could be locked in between two valves or other shut-off points, to prevent liquistatic rupturing. And finally, it is very important to place an excess flow valve as near to the gasser as possible, to minimize loss of dangerous propellent in the case of blown or split hoses, fracture of poppets or sudden seal failure. If the excess flow valve is within the gas house the valve relief opening should be piped to an outside location. The U-t-C gassers make their initial hermetic seal to the can at the flat dust-cover area, or the comparable area, in the case of aluminum containers. A pressure pad above the inner bell is assembled with four "brown" springs (each rated at 175 lbs per inch of compression). The springs are given an 0.065" pre-load compression, so that the set of four creates a force of 45 lbs (20.4 kg). During the initial can evacuation stage, since they do not deflect any more than this, a 45 lb (20.4 kg) force is maintained downwards on the can dome. During propellent filling they are moved another 0.190" (4.8 mm), which allows the inner bell and cap seal to compress hermetically onto the can dome with a force of 133 lbs (60.3 kg). And then finally, for the crimping operation they are deflected an additional 0.440 " (11.2 mm) to provide a downward force vector on the valve cup of 308 lbs (140 kg) while still maintaining the 133 lbs (60.3 kg) force on the can dome. The combined downward force on the can is thus 441 lbs (200 kg). ^ la. ~\ Pt^Ot^LLAuT CVLIWOCR. J/4 6TK.PKg 1-OP-STtttfM.fc r^^ft o- of- &T<co<.enTrLru^ vA L V* ' *■ ■■■■* £=I 1 Figure 31. Nalbach Sepro-Charger Accessory for Their Various Rotary Units In addition to the standard "brown" springs, Kar- tridg Pak can provide Danley "blue" springs having a 310 lb rating per one inch compression, or even "red" springs with a 790 lb rating. For straight propane A108 or some of the higher pressure butane/propane blends (like A90) the' 'brown" springs may not provide a sufficiently strong seal at the can dome, and some blow-by may occur, with consequent light fill weights. This can be corrected by using a diagonal combination of two "brown" and two "blue" springs, for a 185 lb (84 kg) full dome compression, or four "blue" springs, for a 236 lb (107 kg) force. Aerosol cans are made with a minimum 285 lb (129 kg) dust shelf crush, so these forces can be tolerated. Theoretically, a force of 133 lbs (60.3 kg) will handle propellent pressures to 64 psig (441 kPa), but in practice they will tolerate somewhat more than that because of differential displacement compression of the seal. The large downward force exerted in the can during crimping, 441 lbs (200 kg) in the case of "brown" springs, would seem to be sufficient to crush the can. However, the countereffect of the propellent pressure must be taken into account. Nevertheless, many aerosol cans show a clear imprint of the molded cap seal on the arch of the valve mounting cup, indicating the considerable pressures that are exerted at this stage. In some cases, the U-t-C may be used only as a vacuum crimper, with the gassing being done by a downstream T-t-V or gasser-shaker. Kartridg Pak then recommends the use of four very weak springs (e.g. Associated Products No. CO-720-055-1000) which deflect to a force of only 11.5 lbs (5.2 kg) on the container. No valve cup distortion will then occur from the seal. In using a U-t-C gasser as a vacuum crimper, care must be taken not to bottom out on the third cam operation (springs fully compressed) since the container will then crush from the hydraulic pressure. The gassing of Sepro cans, from the bottom, can be handled by the U-t-C gassers, provided they are adjusted to perform this function. The necessary accessories can be installed during manufacture, or a field conversion kit can be provided and installed into existing machines. In 1981, the conversion cost for an existing 9-head machine was $33,000, with exchange of the dial housing. Terco Inc. also produces Sepro can gassers. Their single-head unit will produce 40 cpm at a cost of about $20,000 and a four-head, in-line Sepro-charger (which is still on the drawing board) should run at 140 to 160
404 The Aerosol Handbook cpm and would cost $52,000 in 1981. The propellent weight tolerance is said to be ±0.5g. The John R. Nalbach Engineering Co., Inc. also provides an air-operated, automatic Sepro-charger that can be used with their Model 16-RS, Model VB-16 and Model VB-32 rotary indexing machines, Figure 31. In the "at rest" position the crimping head is up, the Sepro-charger head and the pistons in its two supporting cylinders are down and the propellent charging cylinder piston is retracted and ready to charge. When the indexing starwheel moves the Sepro can into contact with the can sensing valve, the four-way valve on the crimper is shifted and air flows into the top port of the crimping head to perform the crimping operation. At the same time, air flows into the bottom port of the head, raising the cylinder and causing the piston to move up 0.75" (19 mm), which raises the Sepro charging head to seal it against the bottom of the can and open the Sepro valve. Simultaneously, the air flows through the charging cylinder four-way valve and causes the propellent charging cylinder piston to move forward, discharging a pre-set volume of liquefied propellent and forcing it through the Sepro can valve at high pressure. After charging, the "end-of-stroke" sensing valve is depressed which causes the four-way valve on the propellent charging cylinder to shift. This causes the piston to return to its normal "at rest" position. At the same time, it allows air flow into the bottom part of the seating cylinder. The 0.31 " (7.9 mm) motion of the piston in this cylinder seats the Sepro valve. At the end of its stroke, the seating cylinder piston actuates the "end-of-stroke" sensor valve, which then shifts the crimper four-way valve, returning the crimping head and Sepro charging head pistons to their normal "at rest" positions, ready for the next cycle. In smaller and moderate size operations compressed gases (CO2, N2O and N2) are injected into sealed aerosol cans by means of either in-line or rotary gasser- shakers. The rotary devices made by Autoproducts Inc. (formerly Andora Automation, Inc.) are now considered the standard machines for this type operation and in-line machines have almost vanished. The Autoproducts Inc. rotaries are made in 6-head, 12-head and special 18-head models at a 1982 cost of about $3,600 per head. Typical applications include the insertion of CO2 or N2O into windshield de-icers or ether starting fluids, or the injection of these gases into various whipped cream products. The operating rate is dependent upon valve design. A valve with a restrictive tailpiece or small stem orifice can take a very long time to fully pressurize the can. The machines are rated at about 10 cpm/head, but this rate is for wide-open valves, such as the Clayton and Super-Whip valves. In practice, rates are from 50 to 75% this high for most other valves. The ±10% to ±15% variation of valve orifice diameters (depending upon size) also affects gassing rate. If these valves were to be gasser-shakered for a very long time, such as several minutes, all the containers would come to the same equilibrium pressure. But in actual practice, the dwell time (the time gas is actually injected) is around six seconds, and under these conditions the valves with the larger orifices receive more gas and those cans come to higher pressures. The gasser-shaker unit is often the speed-limiting device in an aerosol production line, and for that reason various methods are used to try and maximize its output. Increasing the pressure at the inlet is an obvious approach. With the generation of from 90 to 115 psig at 70°F (621 to 793 kPa at 21°C) pressures in the can as the usual goal, inlet pressures of up to about 200 psig (1.38 MPa) have been used to force the gas in more quickly, particularly near the end of the cycle, when back-pressures in the can become significant. However, the higher the inlet pressure the larger the variation in final equilibrium can pressures will be. Factors like exact time of shaking, valve orifice, fortuitous mixing efficiency, line pressure drops and so forth all become more important under high inlet pressure conditions. Cooling the concentrate generally assists in reducing gasser-shaker time. Whipped cream concentrates are usually filled at about 38°F (3.3°C) to keep the product as fresh as possible; but in some instances, other concentrates are also cooled prior to gassing, to improve rates. For some there will be some optimum temperature between ambient and the practical cooling maximum where gassing is most efficient. Above this temperature, back pressures inhibit gassing rates more, and below it viscosity inhibits gas absorption to a greater degree. When cans emerge from the gasser-shaker, they are not under equilibrium pressure. There is always a significant surplus of compressed gas in the head space, which will largely dissolve in the product after about two minutes of simple mechanical shaking (as with a Red Devil paint shaker), or about five minutes of fairly
Aerosol Production Equipment 405 vigorous hand shaking, or upon overnight standing. In a production operation the equilibrium 70°F (21°C) pressure can be best determined by noting the equilibrium pressure that results after mechanical shaking, then determining the contents temperature using a "skin type" thermocouple and thermistor, and finally converting to the 70°F (21°C) standard by using a temperature correction factor obtained from a chart. Hot Tank The hot tank has always been a vital part of nearly all aerosol production lines, and is actually required for most self-pressurized products under the Department of Transportation (DOT) regulations. With the aim of bringing the can pressure up to at least the equilibrium level for 130°F (54.4°C), the water in hot tanks is maintained at from about 140° to 165°F (60° to 74°C), depending upon product formula, can size and container strength. For instance, the large 300 x 709 (76 x 192 mm) can will sometimes invert at 152°F (67°C) in the case of water-based formulas pressurized with isobutane A-31, and so under these conditions the water bath is best reset at about 145°F (62.8°C). The hot tank serves to detect leaking dispensers, plus those that are lower than normal in pressure resistance. It tends to clean or rinse off unwanted chemical residues on the can, if any are present. Warm cans are almost always easier to paper label. And from time to time, hot tanking will show up unsatisfactory lithographic work, where for instance the top varnish coat is either missing or too thin, causing tackiness or even running of the print coat. An alert operator is a necessity for proper hot tanking of aerosols. Many cans leak at very low rates. For example, if an operator notes a gas bubble attached to the welded side seam of a can, it should be watched carefully for a few feet (a meter or so) for possible growth, thus indicating a slow seam leaker. If a group of these insidious leakers is spotted, a second operator should be added for still more careful scrutiny. In some cases, the second person merely turns the incoming cans about to make sure the welded side seams are directly visible to die regular inspector. Slow CO2 leaks are especially hard to detect because die gas is soluble in water. In diis case, suspected leakers can be immersed individually in a 20% brine solution, in which the gas is essentially insoluble. The smallest commercial hot tanks are the three basket and five basket models. They work best where small non-magnetic containers are being produced, but have been used for all odier kinds of aerosols as well. The basket consists of a heavy steel mesh square container with a lid of similar construction that can be latched in place. Usually, the basket is dipped in PVC to prevent rusting and any scratching of the aerosol units. It is immersed in the hot water tank and then checked to see if any bubbles are produced by the containers. The larger hot tanks have from one to six single- width tracks, or else one or more double-width tracks, each split by means of a stainless steel center rail. Squat "horseshoe" magnets are positioned under die metal tracks every few inches (150 mm) or so for hold-down purposes. Otherwise, cans might slide down the end inclines, become floaters or have odier problems. The total immersion time varies from 30 to 90 seconds, according to length and belt velocity. Figure 32 illustrates a typical double-row Nalbach hot tank with a capacity of about 100 cpm. The unit is preceded by a Kiwi coder and followed by a Nalbach automatic capper. Protective steel mesh covers are shown at die far end of the trough. Hot tanks can be rather dangerous appliances if not used and maintained properly. During die 1970s a filler in New Jersey had a chain reaction of exploding shave cream cans mat literally almost tore die hot tank in two. Had diese cans contained a formula high in hydrocarbon content die consequences could have been even more serious. Many large hot tanks have ventilated Figure 32. Nalbach Double Row Hot Tank and Can Blower i€
406 The Aerosol Handbook hoods for the quick exhaustion of any hydrocarbon gases released from fast leakers or rupturing cans. The enclosures usually have plexiglass observation ports that can be opened easily to wididraw defective cans and are lighted widi explosion-proof fixtures. This type of lighting is available from the Holophane Division of Johns-Manville, Inc. (Denver), and other suppliers. Most baths are die straight-run type, but a few are of die wide bed variety, where cans move back and forth several times on different conveyor belts before emerging. Some of these tanks are eight or more tracks wide. One problem with such models is diat the cans often travel too rapidly, making eddy currents diat interfere widi inspection. Another is diat diey are often too far away for good vision and ready removal of defectives. Some baths are equipped with small pincers diat grip individual cans and carry diem along. This is a good innovation for non-magnetic containers, but is not recommended for over 150 cpm rates. Most baths are heated widi low pressure steam (up to 15 psig or 103 kPa), using steam heat exchangers, or else heat exchangers widi electric elements. Odiers are heated widi commercial gas-fired or electric hot water heaters, or with electric elements or steam coils submerged in die tank itself. The cost of heating hot bath water is often neglected or underestimated. It varies with the aerosol load and with the rate of drainage. Not much can be done about the former, but die cycling rate can generally be reduced to a mere trickle if the dispensers are of good quality and are relatively clean going in. In 1981 the cost of steam averaged $4.00 per million BTU in Canada and $5.10 Figure 33. Hot Tank Showing Water Heater and Pump Nalbach Model 1-L1 I per million BTU in die U.S.A. Aerosol cans require from 10 to about 85 BTU (with a 30 BTU average) for a temperature elevation of 60°F (33.3°C). Considering other losses, from radiant heating, conversion inefficiency, drainage and so forth, a hot tank that uses steam should have a power cost of $300 per million cans. If it uses electric heat, die figure will move up to about $2,000 per million average cans. Blow-off hoods are located at die end of virtually all conveyorized hot tanks. Low pressure air jets blow water out of valve cups and dome countersink areas widi varying degrees of efficiency. Many fillers supplement the blower system widi high-pressure air jets directed at specific hard-to-dry areas, such as under die rim of die valve cup. These jets are often constructed of 1/8" or 1/4" (3.2 to 6.4 mm) copper tubing, pinched partially off at the end. It is important to get die can dome and valve cup as dry as possible, and to delay attaching the overcap for as long as practical, to minimize die possibility of rusting. In critical cases, the cans may be heated a little hotter to expedite evaporation of trapped moisture. Most hot tank water is treated with sodium nitrite (NaNC^) to form a solution of about 0.05% concentration, which acts to inhibit can corrosion to some extent. Detergents may also be added to hot tank water for die purpose of promoting drainage and solubilizing any oily residues that may be on the cans. The choice of detergent is broad. Quite often obsolete chemicals are used, if diey are available. Figure 33 shows die "back side" of a relatively small Nalbach Model 1-L1 hot tank and serves to illustrate the water heating and circulating system. Tipping Machines In some cases, the valve button must be applied by the filler, and this operation is performed either before or after hot tanking. Large size buttons must always be tipped, because the crimping collet cannot ride over them to make the crimp. The acknowledged leader among equipment suppliers in diis small area is the Haumiller Engineering U.S.A., Inc. firm. They provide the Liberty and Super Liberty Automatic Spray Tip Applicator, and in 1981 introduced an air-operated tipping machine at a relatively low cost, rated at 90 cpm. The Haumiller machines are compact, feeding buttons onto valve stems from a revolving, vibrating bowl, then hammering them down lighdy to seat them properly. Any button orientation must be done by hand.
Aerosol Production Equipment Capping Operations Most lines that operate over about 70 cpm are now outfitted with automatic capping equipment. One of the more popular is the "CaPeM" unit, by Consolidated Packaging Machinery Corp. Their Model TG-8-15 provides rates, of up to 300 units per minute. Resina cappers and the Pneumatic Scale Corporation's "Pneumacap" machines are also quite popular. Other makes are also available. One of these is the specialty capper made by Nalbach for "stalk-type" (Clayton and Super-Whip) valves. The caps are applied from a sorting helix, where they are positioned upright and dropped over the valve, they are then centered and pressed down forcefully, enabling the plastic lugs to grip under the rim of the valve cup. The cap placing unit has a Geneva Drive to facilitate a smooth, fast operation. Similar units are made by Aerofill Ltd. and other suppliers. The Nalbach machine is illustrated in Figure 34. Aerosol Can Packaging A number of operations take place at the end of the aerosol production line, and many of them are performed mechanically on the larger installations. The aerosol case loader machines replace one line operator for about every 40 cpm of line speed. Cases are set up either by hand or with the aid of a box-maker and are fed to the case packer via a skate wheel or roller conveyor. In the packer, collected cans are dumped into the waiting carton through thin shives. Once filled it is given a sideways shove onto a second conveyor, where it travels to the case sealer. Roller conveyors used in this area may be energized using a padded chain drive, such as those available from the Rapistan Division (Grand Rapids, MI), their Model 1276, or filled cases may be raised using a rubber-belt conveyor and deposited on a simple skate- wheel or roller type, pitched downward slightly, so that a row of cases can be fed to the case sealer. In the sealer, normally both top and bottom outside carton flaps are glued, and then closed and compressed against the inner flaps for 30 seconds or so to make the seal. Other sealing options are used less commonly. For instance, the case bottom can be stapled shut with a device such as the Bostitch Division's FC95-B motorized carton bottomer, using wide crown copper-toned staples. Some marketers prefer to use tape to seal carton tops. During the compression cycle, while the glue seizes, 407 case codes are able to print identifying information on the side or end wall of the box. A few are able to code simultaneously both side and end sections. Case sealing systems are made by Standard Knapp Corp., the Elliott Manufacturing Co. (Model 68-12), and in England by Paklocker, Ltd. (Andover, Hants). Some of the Standard Knapp equipment is over 40 ft (12.2 m) long. Completed cases are usually stacked on pallet boards by hand, often using a two-sided steel frame to bump the cases against. However, a few firms offer automatic case palletizers, such as the Currie Machinery Co. They are large machines and often become still larger when conveyor in-feeds are considered. During recent years, pallet wrapping has become fairly popular. Pallet wrapping turntables with a spiral elevator design provide for the ascent and descent of the polyethylene wrapping film. Economical "Victory" and "Commander" machines are available from Stevenson Industries (Chatsworth, CA), and in Europe from Ballinger-Rawlings Ltd (Watford, Herts, England) and Lantau BV in Holland; e.g. their "FLM Savr System". Future Aerosol Filling and Packaging Equipment Current indications suggest a trend toward moderate speed, no frills equipment, at least in the U.S.A. Lines are available in the 60 to 120 cpm range, where only 7 or 8 operators are necessary. They can often be purchased for less than $200,000 in 1982 dollars. When they are inevitably compared with high-speed production lines, able to go about twice as fast, using twice as Figure 34. Rotary Cap Placer Machine and Sorter
408 The Aerosol Handbook many operators, and costing several times as much, it can be persuasively argued that two moderate speed lines may very well offer better overall economics than one large, sophisticated, high-speed line. The smaller lines also provide quicker changeovers and can therefore handle smaller production volumes more efficiently than the high-speed types. Many contract fillers, who use only moderate speed equipment, do not consider the contract fillers with only high-speed facilities as true competitors. They aim for business in the area of 5,000 to 50,000 units per order, knowing that the larger fillers generally "bottom out" between 25,000 to 50,000 units per order, due to the need to flush large tanks, complex handling equipment and fillers, plus the fact that their change-overs may require many hours of work. If a production line must be changed over to a new product during normal production time, then there will be a lengthy period where all the investment in equipment, "brick-and-mortar" and labor produces no income. Considering a high-speed operation running on a two- shift basis, it can be suggested that individual productions of less than 160,000 to 200,000 units will force a changeover during the normal work period. In fact, even with runs of this many units, if the production is started during the work period, a changeover will be required during work on the following day. High-speed lines often produce far less than the theoretical numbers of units, and return on investment (ROI) is often much less than anticipated, simply because of the very high cost of changeovers. As the present high cost of money continues into the 1980s, it is likely that one result will be an increasing interest in the moderate speed production lines. ' During the 1980s increasing attention will be given to the six basic criteria that affect the productivity growth of a plant: a. Manpower — planning, training, control, reduction of absenteeism. b. Capital budget control. c. Quality control/assurance. d. Purchasing control. e. Maintenance control. f. Cost control. In the manpower area, more attention will be given to management planning, the annual budget cycle, departmental objectives and management performance. Formal training will increase as business becomes ever more complex. Probably 1 to 2% of the total work force will be doing nothing but training for higher positions. Plants will perform productivity objective analyses. They will include lost time due to accidents as a per cent of total hours worked, the absenteeism rate — which is expected to cost the U.S.A. $115 billion and Canada about $9 billion in 1982, or about eleven times as much as strikes — and "idle time" on the job. Most labor utilization figures are calculated only when a line is running and are therefore not a total picture. "Idle time" data should be dollarized. Periodic capacity planning should be undertaken to forecast labor and other needs and thus avoid expensive catch-ups. In the typical well run aerosol production plant, capital funds are spent about as follows: a. 16% for existing products — to maintain current capacity. b. 27% for existing products — to increase current capacity. c. 44% for cost reduction. d. 3% for new product requirements. e. 10% for "necessities" — safety needs, security programs, employee comfort, etc. During the next few years, other plants may move closer to this balance of interests. For many of them, there will be a decreasing desire to increase current capacity, but to aim selectively more for cost reduction. This will eventually mean the maximizing of profits from operations(PFO) as a primary goal and maximizing return on investment (ROI) as a secondary one. Quality control/assurance will be increasingly looked upon as a productivity improvement tool, and eventually this will also be applied to a major portion of the research and development effort. In 1982, probably fewer than 5% of U.S.A. aerosol firms maintain any quality control cost analyses. Typical costs in a well run plant now run about 30% for "failure", 60% for "appraisal" and 10% for "prevention" — such as planning, maintenance and improvements. Great stress will be placed toward the reduction of "failure", since mistakes are becoming more and more expensive, and the public is less tolerant of business errors. The quality control/assurance program should cost about 5% of the direct costs for the average aerosol plant. It will obviously be higher for plants involved in pharmaceutical or food activities, probably approaching 8% or so as a limit. If the cost is greater than these figures, an analysis of the quality oriented activities should be made with reduction of "busy work", scrap
Aerosol Production Equipment 409 analyses, rework activities and so forth in mind. Many plants currently discard over 2% of their incoming components and chemicals as scrap. In one notable instance, a well organized program to reduce scrap from 1.7% to a lower figure was initiated in 1978. Plant personnel were advised of the cost of materials and the cost of plant scrap each month. A second checkweigher was installed on each line, after the concentrate filler. There was more surveillance and more questioning of the reason for scraping cans. By mid-1980 the scrap rate was reduced to 0.66%. The increasingly high cost of materials will make such programs more commonplace during the 1980s. Under purchasing control, increasing attention will be given to maximizing trade discounts, allowances, rebates and similar benefits. The practice of' 'ordering well ahead" (to ensure production schedules) will be optimized in view of the high cost of money. Purchasers will increasingly ask suppliers to have their anticipated needs produced and set aside, for shipment no earlier than it is actually required. For example, some propellent suppliers now park tankcars on sidings a few miles from the final destination, so that delivery can be made more expeditiously upon the customer's release. Services of this type will increase. Maintenance control will be upgraded and many haphazard activities done today will be formalized in the future, such as check-off lists for lubrication schedules and analysis of parts replacement needs to predict minimum future needs and highlight possible problems. Maintenance people will be better trained and organized in their activities, with more attention given to preventive actions than to ' 'putting out fires.'' Finally, under cost control there will be increasing use of computer technology to expedite data collection and analysis. Microprocessors will be Used more often to smooth and sophisticate production operations. For instance, MPs could speed up lines to achieve optimum conditions or slow down certain sections to allow for possible breakdowns. They can also sense impending motor or drive failures on the basis of variant amperage draws. A micro-processor-based quality control system will provide a way to reduce errors and labor requirements in weight checking procedures. A typical system, such as that recently afforded by the Syscon Corporation's QCT-1000, will automatically record weight deviations, signal out-of-tolerance conditions for every head of both filler and gasser, and totally eliminate the present need for manual data recording of tare and filled weights. By 1982, the only chemicals not costing at least $0.30 per lb. ($0.66 per kg) in bulk were water, CO2, the hydrocarbon propellents and some of the lower-grade hydrocarbon liquids. Because of this, there will be added pressures on suppliers of filling machines to increase accuracy as a means of reducing the average concentrate filling weight per can. A few super high accuracy fillers are available, and we can recite as an example the Oden Corporation's (Suffern, NY) Pro/Fill 2000 solid state filler, with digital computer logic controlled process circuitry. This interesting machine exhibits up to ±0.1% accuracy at speeds up to 75 cpm. The filling range is from 0.1 ml on up, and it can handle rather viscous lquids and gels, strong acids and bases, high-foamers and low-foamers, hot fluids and cold fluids, and thixotropic or rheopectic emulsions. It also has an electronically controlled anti-drip system. Expansion modules are available for multiple fill station capability, within the 4.0 gpm (15.1 liter per minute) maximum flow rate per port. Machines of this sophisticated nature will probably replace the "nonelectronic "types in time. During the decade of the 1980s we forsee the commercial develoment of various all-plastic aerosol containers, and their production utilization starting about 1983 or 1984. By the end of the decade, they will probably account for more than 50% of all aerosol containers, mainly because of economics. Eventually even valve cups will be replaced with plastic fitments that hold the valve components and seal onto both the inside and outside of the bottle finish using a thin polyethylene gasketed multiple set of barbs on each surface. The development of these components will have a profound future effect upon aerosol production. The bottom of the PET or other plastic bottle may be shock-jacketed with a magnetic plastic snap-on fitment to facilitate can handling. Special design features at the top of the bottle may allow the survival of U-t-C gassing techniques, but at the expense of extra plastic there. Otherwise gassing will have to be done on a T-t-V basis. In summary, great challenges lie ahead in the filling and packaging of aerosols, and the industry will survive and prosper by using them to their advantage, as they have done with so many innovations in the past.
411 THE AEROSOL LABORATORY 12 Figure 1. Statistics of New Product Development ONE SUCCESSFUL 20% 30% 40% S0% 60% 70S »N 90S B«u>ulta 1 H«Mlto* in ftttuiOi MWrtnHM Research and Development activities have done much to create the present aerosol industry. Indeed, many of the more renowned figures in the industry started out in research, developing new cans, valves, formulations and so forth. During 1982 it is estimated that some $48 million will be spent for aerosol research by marketers and contract fillers alone. In terms of real dollars diis represents a figure about on a par with that of $27 million in 1972. Before 1972 research growth ranged between 7 to 11% per year. Afterward there was a severe slump from 1973 to 1976, followed by a catch-up period of growth as research teams strove to convert thousands of aerosol products from the condemned chlorofluorocarbon propellents generally into hydrocarbon types. We are now on a plateau. Probably the greatest slump in true research and development has taken place within the contract filler area. In 1982 contract filler research will probably not exceed about $4 million. Only a small fraction of that will be spent in new product development, since there are very few new product possibilities left these days and such programs are very costly. A recent analysis by Booz • Allen & Hamilton Inc. suggests that there are about 58 new product ideas for every actual development of a new commercial product. If the idea is generated by a marketer and is screened before sharing it with a contract filler with a request to develop it the odds drop to about 13 to 1. The statistics are more fully laid out in Figure 1. There has historically been an unwarranted level of optimism that new product ideas brought to contract fillers (or to research departments in general) will culminate in new products. Actually, only about 10% become commercial, depending on how much screening and business analysis has been conducted beforehand.
412 The Aerosol Handbook When an idea for a possible new product is brought to a contract filler for development, a number of factors should be considered before a commitment is made. Some of these are now listed and explained. a. Is the product possible? i. Is aerosol hardware available? ii. Are the anticipated chemicals compatible with the dispenser? Are there any regulatory barriers? Can the desired claims be achieved? Are the economics reasonable for the intended use? m. IV. v. vi. Is the assembly within reasonable production limitations? b. Will the program have reasonable proportions? i. Will the usual interminable time periods be needed to obtain Underwriter's Laboratory (UL), Factory Mutual (FM) or Good Housekeeping (GH) approval? ii. Will special approvals be required by the EPA, FDA, DOT or other agencies? Will special hardware have to be developed by others? Is success related to a New Drug Application (NDA) or other long-term activity? Is the quality of the inquiry sufficient? in. IV. O- OOOOOOS " METAL THICKNESSES AKE MlflLr TRANSPARENT OMOOCJ' METAL THICKNESSES ARE TRANSLUCENT O 10 E" W J s Figure 2. Pictorial Comparison of 0.1 OW ETP and 0.25# ETP Steel Plate i. Is the inquiring firm actually a marketer, a distributor, or a person with an idea? ii. Is the firm currently selling aerosol products? In what volume? iii. Is the proposed compatible with the product mix of the firm? iv. Does the product idea have top level support . . . or is it simply an idea by one or two people who would like outside assistance? v. Is the firm currently a customer? vi. Is the firm financially sound? vii. Has screening and some degree of business analysis been done on the idea? viii. Is reasonably sustained business likely to result? d. Miscellaneous aspects. i. Would the product seem to have a reasonable chance of success in the market? ii. Are there any patent or trademark impediments? iii. Are significant capital commitments needed for production? And will these be picked up or shared by the inquiring firm? iv. Does the filler have people and talent available for the requested project? v. Is the anticipation of developmental success reasonably high? vi. Has the inquiring firm been offered a preliminary quotation and found it to be acceptable? [Relates to a.(v.)] Inquiries which should generally be turned down politely might include requests for a barrage of ten or more product types, requests for co-dispensing aerosols, and a suggestion from a person with a few wealthy friends for a few "new and different" products for evaluation. On the other hand, requests for reasonably standard, off-the-shelf aerosol products can be handled easily. Much research is now directed toward reducing costs, a's it always has been; but now there seems to be an added urgency or impetus. For example, tinplate cans are now available (in 1982) with 0.10/0.10# ETP and 0.10/0.20# differential ETP systems. The difference between a 0.10# ETP finish and the minimum 0.25# ETP finish of previous years is illustrated in Figure 2.
The Aerosol Laboratory 413 The canmakers feel that the electrochemical protection afforded by 0.10# ETP is the equivalent of that provided by conventional 0.25# and even 0.50# ETP finishes. Cans with the thinner tinplates cost from about $1.00 to $3.00/M less because less weight of expensive tin metal is used, and this has given marketers an incentive to use them if possible. The task then falls to the research laboratory to see if these new cans can truly contain various aerosol products as well as the older ones, or at least well enough for commercial uses. In the case of certain stripping-type detergent solutions, it was found that iron could be dissolved more rapidly in the case of 0.10# ETP cans, turning the product from essentially water-white to a light straw, then amber and finally to dark amber (due to colloidal iron oxide hydrates), over a number of months of ambient storage. By the application of a relatively high vacuum: about 20 "Hg° ( - 68 kPa), this development was significantly slowed, since dissolved oxygen was a key factor in the solubilization of iron. But, this finding brought researchers into conflict with yet another cost-reducing innovation by the can companies: the use of DR-8 (double reduced - effective temper of about 8) body plate which could be used at thicknesses as low as 70# for 211-diameter (65 mm) and 75# for 300-diameter (76 mm) cans. While these extra tough plates were quite satisfactory in holding pressures, they were slightly deficient in holding vacuums without crumpling. Under dynamic production conditions vacuum crimps higher than 16 " to 17 "Hg° ( - 54 to - 58 kPa) might cause crumpling, sometimes also called "paneling". Without the ability to draw the higher vacuum levels, the aerosol cans would still be subject to slow product discoloration. In 1982 still another can making innovation occurred. It was found that completed welded can bodies (unflanged) could be compressed carefully into thin ovals, about 5 to 6 times as wide as they were high, con- veniendy shipped to satellite plants where they would be rolled round again and flanged, and then have the end sections attached. In the rounding process there is the possibility that extremely small "micro-cracks" may form as the tin metal is stretched at both ends of the oval. This would cause a general breeching of the protective coating and a lesser breeching of the electrochemical protection. These cans would have to be examined for continuing compatibility with existing aerosol products. These three examples of innovations in the can making field point up the defensive need for research on present aerosol formulations. When valve innovations, filling changes and other attributes are included, this type of activity can represent a significant portion of the workload of an aerosol laboratory. The new all-plastic aerosol containers, scheduled for introduction in about 1983 or 1984 in the U.S.A. (and perhaps earlier in Europe), will cause an enormous amount of research of this type, aimed at determining compatibility, strengm, solvent effects, permeation rates and so forth. In many aerosol plants the research department is increasingly called upon to resolve difficult production problems. These may involve can leakage, can corrosion, valve pluggage, phase inversion of emulsion systems and so forth. In some cases, research groups may work on the development of improved crimping collet designs, better and simpler adapter designs, and on ways to reduce chemical losses during the compounding, handling and production operations. These activities either make or save considerable sums of money for the company and are thus strongly encouraged. Many aerosol laboratories are add-ons to existing research facilities. There are almost no "pure" aerosol laboratories, since few if any firms are engaged only in the business of making or selling aerosol products. Nearly all contract fillers also have liquid facilities and some also fill powders, tubes and other product forms. In many research facilities operated by major marketers, the aerosol laboratory and possible pilot plant are merely one section or division in the overall research center. In this setting many of their technical requirements are supplied by other units in the center. Some of these inputs may include: a. Literature and patent searches. b. Analysis of competitive products. c. Use of instrumentation as an aid in formulation. d. Clinical studies to assure product safety. e. Microbiological studies to insure product safety and stability. f. Small "focus group" workshops to provide consumer evaluation data. g. Government registration for economic poisons and certain other products. h. Pilot plant studies to determine the production limitations or adaptation.
414 The Aerosol Handbook i. Development of analytical methods manuals for proposed products. j. Consultation. The independent aerosol laboratory must respond to the challenge by adjusting to handle those special areas which can still be brought within the scope of their bud- getry limits, or by arranging to have at least some of them handled by outside consulting laboratories or by suppliers. Consulting laboratories are used by small and large research laboratories alike. Typical requirements best handled by the consulting firm are: a. Special microbiological assays. i. Studies on M. tuberculosis, for "Tuberculoci- dal" label claims. ii. Studies on Influenza A2 virus, for "Virucidal" label claims. iii. Studies on CI. botulinum, for specific bactericidal information. b. Trace metal determinations; e.g. iron, tin, lead and copper. c. Clinical studies, to assure safety. d. Clinical studies, to assure efficacy. e. Entomological studies, such as Peet-Grady fly- chamber tests. The essential responsibilities of the aerosol laboratory include research, development, scientific liaison and quality control. The chemically oriented activities of quality control are often taken care of in the general laboratory, but as companies get larger and inevitably become'more departmentalized, these functions are frequently separated into an indendent operating unit. In the aerosol industry, true research is generally linked to the creation of new and improved products. Thus it becomes equatable with formulation, plus container selection. After research has brought the aerosol package into existence, the development phase then takes over. Further tests are conducted to assure the company that the package is a potentially marketable commodity. Quite often the research man will handle many phases of the development program. Formulation An aerosol formulation can usually be considered as a composite of three segments: a. Active Ingredients — those chemicals which characterize the product. b. Solvent/Diluent System. c. Propellent. The determination of optimum percentages is usually most difficult in the case of active ingredients. The formulator can usually rely on many sources for assistance in arriving at approximate levels. Some of these are: a. Previous work done in the laboratory. b. Supplier literature or comments. c. Library sources, including aerosol oriented periodicals. d. Analysis of competitive products. e. Label declarations on competitive products; especially economic poisons and medicinal items. f. General knowledge. g. Testing of prototype formulations, h. Government restrictions. A typical situation of this type can be illustrated in the case of the development of an aerosol first aid spray for cuts and abrasions. Some elements of the formula- tive thought processes might be: a. What bacteriostat(s)? Hexachlorophene would be ideal at about 0.025 % in a formula high in volatile ingredients, but the FDA has, for all practical purposes, placed a ban on its further use. A good replacement is Ciba-Geigy's "Irgasan DP-300" (or "Triclosan") since it has had the benefit of a great deal of testing on the skin, with very good results. "Irgasan" is reportedly 20% to 40% stronger than hexachlorophene, so use about 0.020%. Since "Irgasan DP-300" is weakly effective against Pseudomonas and certain other microorganisms, a back-up bacteriostat is desirable. Most dermal flora are Gram-negative, and these are best controlled by means of quaternary ammonium salts. Use BTC-50, which is specifically approved for skin applications and is one of the more efficacious of the old reliable types. According to literature, and considering evaporation, 0.015% should be adequate as a minimum. Since blood, serum and certain proteins partially deactivate quaternaries, perhaps 0.020% would be a more realistic figure. b. Topical pain killers? Choices are benzocaine, n-butyl-p-aminobenzoate, Lidocaine (Xylocaine)
The Aerosol Laboratory 415 and others. Benzocaine is probably best because of an elaborate history of safe use. It is compatible and relatively low in cost. About 0.30% should do. This will concentrate to 10% on the skin. c. Perfume? Possibly a trace of lemon . . . Perfumes are not normally used and might even irritate. Use chlorothymol if an odor is needed. d. Carrier? Some extremely bland solvent is needed, mainly to hold the active ingredients onto the skin. Isopropyl myristate and isopropyl palmitate are poor solvents for the quaternary. Oxo-process hexadecanol is too oily. About 3 % of Polyglycol 600 is liquid, non-oily and will keep the scab relatively soft. e. Co-solvent? Polyglycol 600 sometimes needs assistance to dissolve in propellents. The addition of about 3% of either ethanol or isopropanol will maintain phase stability down to about 50°F. Isopropanol is preferred since this eliminates AT&F ethanol regulations and problem of adding denat- urants. Odor difference is of no consequence at proposed use level. Very slight sting will be considered as a sign of effectiveness by many users. f. Other ingredients? Subjective area. Use of allan- toin might promote more rapid healing, but FTC requires direct proof of such claims, which would escalate costs of clinical program. So forget it. Use of dyes is contra-indicated because of scattering effect of spray and possible misuse. g. Principal solvent and diluent. Propellent-11 is best, since it is bland, non-inflammable and evaporates readily. Is a fair solvent for ingredients. However, while this would be acceptable in Canada, Europe (except for Norway and Sweden) and the rest of the world, the use of P-ll for this purpose is banned in the U.S.A., so a substitute solvent and diluent has to be found. The two most logical candidates are ethanol and water. Ethanol has the disadvantages of flammability, sting and cost. An aqueous product will require shaking before use and must also include one or two emul- sifiers. The corrosion potential of the product would have to be determined in whatever can is desired: tinplate or aluminum. h. True propellent. From 24 to 28% P-12 will give an ideal spray, where its use is permitted (see above). Higher levels will cause "fines" to get into the nasal passages, where some irrit&tion might result from the quaternary compounds. The addition of about 7.5% propane A108 or 25% isobutane A31 could be considered as a replacement for the P-12 to save money. If ethanol is used instead of P-l 1, then 35% isobutane would be a reasonable propellent choice. In the case of water-based formulas one could consider 32% A46 or about 40% dimethyl ether (DME). These considerations would then result in the establishment of a prototype formula. In the case of the P-ll and P-12 option it might be the following: Formula 1 First Aid Spray for Cuts and Abrasions 0.02% Irgasan DP-300* (Ciba-Geigy, Inc.) 0.02% BTC-50** (OnyxChemical Co.) 0.30% Benzocaine, USP 2.66% Polyglycol 600*** (Dow Chemical Co.) 3.00% Isopropanol — anhydrous 70.00% Propellent-11 24.00% Propellent-12 * 2-Hydroxy-2',4,4,-trichlorodiphenyl oxide. ** Alkyl dimethyl benzyl ammonium chloride — 50%. **• PoJyoxyethylene glycol. The formulation of this product is relatively simple, yet even here it is seen that a number of ingredient interrelationships apply. The BTC-50 broadens the antimicrobial spectrum of the Irgasan DP-300, for instance. The effect of one or more ingredients on another must be kept in mind during most formulation activities. Typical examples are: a. Co-solvent Effect. Semi-polar ingredients such as ethanol, isopropanol, acetone and methylene chloride can bring immiscible liquid phases together. b. Combination emulsifiers of different HLB (Hydrophilic/Lipophilic Balance) values usually act more effectively than either one alone. c. Water scavengers, such as 1,2-propylene glycol or epichlorohydrin, act to remove traces of moisture from oil-based formulas containing DDVP (2,2-dichlorovinyl dimethyl phosphate — Vapona) or carbon dioxide. Otherwide items such as dimethylphosphoric acid and carbonic acid would form and cause product deterioration, can corrosion or both.
416 The Aerosol Handbook d. Toxicant synergism is nearly always used in the case of pyrethrins and allethrins insect sprays. Typical synergists are piperonyl butoxide and MGK-264 (N-octyl bicycloheptene dicarboxi- mide). Some toxicants, such as SBP-1382, do not require synergism. e. Preservatives are often used to protect sensitive ingredients against bacterial attack. Most cosmetic emulsions, all starches and some food products are susceptible to degradation unless preservatives are included. f. The addition of non-ionic detergents and certain other ingredients has the effect of inactivating phenolic bacteriostats and must be generally avoided in such formulas. But in a few instances such materials act as enhancers. g. The addition of anionic detergents to formulas containing cationic detergents, bacteriostats, softeners, rinses and so forth will result in deactivation, and even precipitation. A more complex formulation is an aerosol shaving cream. Here it often helps to set forth a product profile that can be used as an aid in devising prototypes. Profile factors that should be considered are: a. Firm, stable foam. i. Dense foam. ii. Good texture. iii. Good handle. iv. Smooth consistency. Use palmitate/stearate soaps, modified with coconut soap. Potassium stearate up to 0.5% often gives more body and a denser foam. b. Emulsion Stability. Include glyceryl monostearate, generally as the self-emulsifying, acid-stable mixture with poly- oxyethylene stearate. Also include up to 10% Tween-20/Tween-80, or up to 4% Arlacel 165. c. Rich, copious foam. Use 7% to 9% total fatty acid, including myris- tate (preferably) or stripped coconut fatty acids up to 12% to 24% of this total. Triethanolamine gives an aura of richness to foams, especially at over 20% coconut acids. d. Non-irritating foam. Avoid ordinary coconut fatty acids, which contain up to 4% capric acid, C9Hi2- C02H. Include about 0.15% of PVP K-30, which functions as an anti-irritant. Select perfumes with care. If desired, add 0.05% maximum of DL-Menthol; undetectable by odor, but capable of exerting a mild cooling effect on skin. e. Good foam appearance. Add up to 0.5% cetyl alcohol to get velvety texture. Also helps add body. Enhance shape retention by including 0.10% PVP K-30, or up to 0.80% Veegum. These polymers also give good sheen and more consistency. f. Whisker wettability. Increased by adding sodium lauryl sulfate at up to about 1.50% A.I. Also by use of other auxiliary emulsifiers, such as polyols, self-emulsifying glyceryl monostearate, lauric diethanolamide and specific Arlacels. g. Close shave lubricity. Retain 1 % to 3 % unreacted fatty acid. This provides superfatting action, plus more lubricity and emolliency than soap itself. Over 3% may give formulas a pearly sheen. Diethanolamides also provide superfatting action and lubricity. h. Razor glide. Silicone fluids are of some benefit if properly selected. Coconut oil is better, and lauric diethanolamide types are best. i. Long drying time. To keep lather wet longer, add 3.5% to 10.0% of polyols, Sorbo (sugar alcohol), glycerin or similar humectants. Use of auxiliary emulsifiers has some effect, so that only 3.5 to 5.0% of humectants are needed. j. Corrosion inhibition. Not normally a problem. For tinplate, use 0.04% borax 10 mol, and for aluminum use about 0.25% of sodium silicate 35°Be. solution. k. Water dispersibility. Good rinsability of remaining foam on face and razor crevices is obtained by including hydrophilic emulsifiers, such as Tween-20. 1. Dispensing properties. Dictated by propellent selection. Use 2.9% to 3.5% A-46 blend for the best results. (Fluorocar-
The Aerosol Laboratory 417 bons will usually give finer textured foams at 6.5% to 9.0%, but are too expensive, even though the Spitzer Patent has expired.) m. Freeze-thaw stability. Not normally a problem if over 3 % glycerin or similar humectant is present and significant amounts of oils are absent. n. Product preservation. Not usually needed. One formula containing sodium lauryl sulfate required routine preservation. Where coconut oils, oleates or ricinoleates are used, add an anti-oxidant such as 0.012% BHT, in order to avoid possible rancidity. o. Dermal antisepsis. Use of 0.05% ofIrgasanDP-300, 0.05% Vancide BN or alternate bacteriostats is sufficient to inactivate most skin-resident bacteria. Helps reduce possible infections from acne or razor cuts. p. Can retention. Use of excessive amounts of thickeners, gellents or pituitous ingredients will cause retention of an excessive amount of product in the "emptied" can. This must be corrected by reformulation or overfilling. q. Emolliency. Conferred best by hydrophilic lanolin derivatives, such as Lanol, Lanogel 21, Atlas G-1441 and so forth. Also a property of free stearic acid. r. Good application. The ability of the foam to be applied as a smooth, even layer upon the face depends upon fineness of bubble structure, presence of thickeners, humec- tants and other special ingredients. s. Perfume selection. Floral, citrus and light non-descript perfumes are used most often. Lemon-lime is a favorite. Levels range from 0.15% to 0.65% depending upon potency, positioning of product, and other factors. t. Color selection. Obtained through use of D&C or FD&C dyes. Pastel yellows are most popular for men's shave creams. Nacreous or pearlescent ingredients can be included for special effects. u. Unique ingredients. Allantoin TGA (200 mesh) may be added at about 0.05% to promote more rapid healing of cuts. (Should not be so labeled, since this amounts to a drug claim.) Special wetting-type formulas, when used with an excess of propellent, will enable the claim of "Twice as much foam per can" to be made. Use of Purcellin oil, Mink Oil and similar specialty oils gives special spreading and skin softening properties. Adjust formula to leave oil on skin by maintaining pH below 8.9 and so forth. Use of special organic compounds can sponsor the claim of "Protects blades. Makes them last up to 30% to 50% longer." Elimination of sodium and potassium ions in favor of triethanolamine, while not giving a superior product, can result in the claim of "Contains no metallic compounds." (This might be considered as an unfair practice, making the most of the present ecological turmoil.) Further considerations are necessary when formulating self-heating or externally heated shave creams. In the latter case, the dispenser must operate satisfactorily without preliminary shaking, and the ingredients must be heat stable to at least 200°F. Triethanolamine, which is not particularly heat stable in a shaving cream environment, turns the product tan or light brown. Perfumes may also give problems. Application of the concepts developed in the shave cream product profile lead to the following typical formulation: Formula 2 Aerosol Shaving Cream 4.85% Double-pressed Stearic Acid 1.60% Stripped Coconut Fatty Acids 4.30% Triethanolamine — 99% 0.35% Triethanolamine Lauryl Sulfate 8.00% Glycerine — 99% 0.75% Veegum 0.03% IrgasanDP-300 0.32% Perfume 0.06% DL-Menthol, USP 76.89% De-ionized Water 2.85% Propellent A46 16w% Propane A108 84w% Isobutane A31 (R.T. Vanderbilt) (Ciba-Geigy, Inc.)
418 The Aerosol Handbook Quite often, the cost of a formulation must be limited to some predetermined figure per thousand cans. Even though cost cutting can be an agonizing finale to the development of a superior formulation, it is, nevertheless, a fact of business life. Typical approaches to cost reduction can be given for the shaving cream formula: a. Eliminate the expensive DL-Menthol, USP. b. Replace the 8.00% glycerin, with a mixture of 5.00% glycerin -and 3.00% propylene glycol. c. Use a less costly perfume. d. Use 85% grade of triethanolamine. e. Use a slightly higher ratio of stearic acid to coconut fatty acids. f. Use a reduced net weight per can. g. Eliminate the Irgasan DP-300. In the case of shaving creams and most other water- based aerosol products the so-called solvent-diluent and propellent portion cannot be further reduced in price. But in anhydrous systems the large-percentage ingredients offer prime targets for savings. An insecticide marketer with sales of about 2 million bug killer cans per year changed to a low-odor petroleum distillate which cost about $0.01 per gallon less than the previous one and saved over $2,500. Most anhydrous formulas contain a balance of hydrocarbon propellent and solvent and perhaps either methylene chloride and/or 1,1,1-trichloroethane; so that, with the proper choice of valve, the spray will often not be classed as "Extremely Flammable" or "Flammable" under the conditions of the Flame Projection Test, Closed Drum Test and Modified Tag Open Cup Flash Point Test. These tests are fully described in the Flammability Chapter. A great deal of balancing, or "fine-tuning'' is usually done in order to achieve the best product with a low cost and as little flammability hazard as possible, when used correcdy. Once the aerosol laboratory has formulated a new product, it must be tested to establish not only conformance with regulations, but good performance in the hands of the consumer. The product can be evaluated in accordance with standard laboratory check lists, such as the following: a. Formulation i. Is formula compatible over temperature range anticipated during use? ii. Can formula be filled using available production equipment? iii. Is the propellent blend consistent widi production and storage limitations? iv. Is the pressure sufficient, yet not excessive? v. Can formula be compounded and filled without special hazards of toxicity, irritation, flammability and so forth? vi. Can desired weight be placed in container while still maintaining head space requirements? vii. Is product non-flammable, as dispensed? viii. Is pH value consistent with application? ix. Has lack of toxicity been established? x. Is formula as inexpensive as possible? xi. Does the product perform as indicated on the container label? xii. Is can retention minimal? xiii. Is formula highly effective for intended use? xiv. Is product delivered in acceptable form throughout life of container? xv. Does product conform to all applicable regulations? b. Dispenser Compatibility i. Does product affect container adversely? Check for: Can perforations. Pressure increase — aluminum cans only. Plastic botde permeation or distortion. Can lining effects — blistering, stripping or dissolution. Rust formation. Detinning effects. Valve deterioration — gasket swelling, "blow-by", nylon/alkali problems, diptube distortion or button fall-off. Valve plugging. ii. Does container affect product adversely? Check for: Product discoloration. Changes in product odor — tinny odor or gasket plasticizer odors. Emulsion breakdowns — often due to polyvalent ion generation.
The Aerosol Laboratory 419 Formation of complexes or clathrate compounds. Formation of sludge products. Changes in taste, for food products. Other organoleptic effects. iii. Has adequate storage experience been obtained? Ideally, a twelve month canmaker's warranty should be available. In-house 70° and 100°F (21° and 38°C) storage should provide good results for at least six months. Data for weight loss should indicate ability of dispenser to hold formula without excessive seepage. Spray rate and spray pattern should remain good after several months of 70° and 100°F (21° and 38°C) storage. iv. Have simulated use studies been made? Check for: Changes in pressure as can is emptied. Changes in spray rate and spray pattern as can is emptied. Effect on valve of intermittent spraying — plugging, hard to operate or "vapor-tap" effects. For emulsions: effect of shaking can versus not shaking. Effect of product on overcaps, dome enamels or button attachment. Effect of predictable consumer misuse. Changes in seepage rate as container is used. In-home problems associated with use of dispenser — rust rings, paint stripping, furniture spotting, sticky deposits on can. c. Quality Assurance i. Are individual ingredients susceptible to physical and chemical analysis? ii. Can concentrate be analyzed for presence of all ingredients? iii. Can concentrate and finished aerosol be analyzed quantitatively for key ingredients, such as toxicants? iv. Can product be produced under acceptable control conditions? v. Can product be performance tested quickly, during production? vi. Has a "Quality Assurance Manual" been prepared? vii. Is product sensitive to moisture, carbon dioxide, certain metals or certain types of mixing? viii. Can product be frozen during transit? Where the formulated product is presented in a com- partmented can, with a co-dispensing valve or with some other unique feature, special attributes must be considered also. These can be added to the check list. Lay-Out of An Aerosol Laboratory The floor plan of an aerosol laboratory can take an almost endless variety of forms, depending upon size, functions required and space availability. When the aerosol facility is located within a larger, more general laboratory, one or more rooms should be given over to the aerosol operation. For purely aerosol laboratories, the number of work areas reflects the size of the facility. Three typical lay-outs are listed: a. Small Aerosol Laboratory i. Product Formulation, Quality Control and Storage Area. ii. Adjoining Office Area. b. Medium Aerosol Laboratory i. Product Formulation Area. ii. Quality Control Area, iii. Storage Area, iv. Conference Room. v. Office Space. 1 J2 Li § c ™£Siw IBM] ■ H i u y.ui 18) II El ^ Figure 3. Peterson/Puritan Laboratory, Main Floor
420 The Aerosol Handbook c. Large Aerosol Laboratory i. Product Formulation Room No. 1. ii. Product Formulation Room No. 2. iii. Quality Control Room. iv. Analytical Equipment Room. v. Can Storage Area. vi. Valve Storage Area. vii. Room Temperature Test Storage Area for Finished Aerosols. viii. 100°F Test Storage Room for Finished Aerosols. ix. Chemicals and Propellent Storage Area. x. Pilot Line Room. xi. Office Area. xii. Technical Director's Office. xiii. Conference Room & Library. xiv. Special Services Area; e.g. Microbiology or Focus Panel Testing Room. The Research Center for Peterson/Puritan, Inc., at Danville, IL, is perhaps typical of a large aerosol laboratory. The floor plan is shown in Figures 3, 4 and 5. Within the various rooms and work areas, the layout of laboratory benches, desks, storage shelves, hoods and other furnishings is about the same as for any standard laboratory. Formica-topped benches are usually quite sufficient, and certainly cost less and look better than soapstone or synthetic stoneware tops. Stainless steel sinks can be used instead of corrosion resistant types. The gassing area should be made explosion proof if possible and, in any event, provided with good ventilation to reduce the hazard from hydrocarbon propellent vapors. Since a great deal of spray testing is usually done, it is a good idea to provide one or two hoods for vapor removal. Fluorocarbon vapors can be harmful or at least irritating if released in large quantities in rooms where open flames are present, such as under a hot water heater. Equipment Requirements In addition to the standard glassware, pH meters, electroviscosimeters, stirrers and other routine hardware, the aerosol laboratory requires a large number of relatively special items. There are now several suppliers catering to the unique needs of aerosol research people. Among these are: a. Aerosol Laboratory Equipment Corp. R.D. #1 Route 10 Box 75 Walton, NY 13856 Crimpers, crimp gauges, pressure testers, burette pressure fillers, burst tester, freezers, hoses, connectors, compatibility tubes, etc. b. Aerosol Service A.G. Comes Maschinenbau 21 Steinligasse CH-4313 Mohlin, Switzerland Spray testing device, spring force tester, can curl meter, pressure gauge, flame extension measurement apparatus, COMES FLM PILOT LINE COMPOUNDING AREA 1 1 jo™. ta la Pn fa STORAGE AREA 23'9"*23'4" / \ <c. 23'9" k 34'6" Itnutr, kettlea, pump*. EMPTY ALUMINUM CAN AND TUBE STORAGE AREA Jlllf WORKBENCH RESERVE AREA (For «pannon..l 23"?" x 28'2" / AEROSOL VALVE STORAGE AREA AEROSOL VALVE STORAGE AREA 4'9" x 17'2" EMPTY CAN STORAGE RESERVE STORAGE AREA onf.) EMPTY GLASS t, PLASTIC AEROSOL STORAGE AREA to Figure 4. Peterson/Puritan Laboratory, Second Floor Figure 5. Peterson/Puritan Food Pilot Line
The Aerosol Laboratory c. Field Emission Company Melrose & Linke Streets McMinnville, OR 97128 Faxitron Model #805 X-ray Machine. d. The Kartridg Pak Company 807 West Kimberly Road Davenport, IA 52808 Crimpers, "Under-theCap" crimpers, pumps, leak test tank, fillers, etc. e. EJ. McKernan Company P.O. Box CA Garden Grove, CA 92642 Various new and used equipment. f. Mine Safety Appliances Company 600 Penn Center Pittsburgh, PA 15235 M.S.A. Portable Oxygen Indicator M.S.A. Explosimeter Model #2. g. National Instrument Company, Inc. 4119-27 Fordleigh Road Baltimore, MD 21215 Filamatic fillers, net weighing machines, filters, filling stands, etc. h. Scientific and Process Instruments Division Beckman Instruments, Inc. Fullerton, CA "Aerosol Head Space Sampler and Oxygen Analyzer,", pH Meters, Gas Chromatographs and Spectrophoto- metric equipment. Many devices used in aerosol formulation and testing procedures must be custom built; generally in a machine shop. In some instances prints may be available from the CSMA "Aerosol Guide", supplier literature or other sources. In others the device must be developed from scratch. Typical examples of research and control equipment which must be custom built are as follows: a. Aerosol Flammability Testing Devices. i. Flame Propagation Tester, ii. Closed Drum Tester. iii. Tower Tester. iv. Trough Tester. v. Flame Propagation Tester — Mechanical (Roth) Method: FEA X-601E. (Figure 6). b. Aerosol Viscosity Testing Devices. i. Delivery rate from container under constant nitrogen pressure. ii. Falling ball, released magnetically in glass aerosol. Piezoelectric detection of strike. Standard or solid state electronics. Figure 6. Flame Propagation Tester. FEA X-601 a. b. c. d. e. f. R- h. i. k. 1. m. n. Guide rails. Main switch Frame. Rolls Cotton thread. Micro-switch I. Clamp. Belt. Synchronous motor. Pointer. Scale. Micro-burner. Aerosol container. o. P q- r. s. t. u. v. w. X. z. Support. Lever. Micro-switch II. Sight diaphragm. Pointer for flame flash back Counterweight. Rolls. Control lamp. Fixation screws. Hold down screws for the motor Fixing rolls for the threads. Figure 7. Flame Extension Measurement Apparatus Unit developed for COMES, Aerosol Service AG, Switzerland. Ignition is by an electric arc generated between two electrodes. In this way the inflammability of the spray stream alone is measured. The flame extension is measured visually against a graduated scale.
422 The Aerosol Handbook c. Aerosol Spray Pattern Testing Devices. i. DuPont apparatus with rotating cut-out sector over pick-up surface. Surface modifications include: (a) Glass plate coated with magnesium oxide; photographed. (Dixon) (b) Paper disc coated with talc-plus-dye; photographed. (Root) (c) Absorbent paper, with dye added to test can. (Gunn-Smith & Piatt) (d) Paper treated with phenolphthalein or thymolphthalein; photographed. (Johnsen). ii. Calibrated glass plate held flat. Sprayed from a fixed distance, such as seven inches. For starch dispersions and detergent sprays. d. Particle Size Testing Devices. i. Battelle Institute "Cascade Impactor". ii. Malvern ST-1200 Analyser; Malvern Instrument Company. iii. BAMA Method. Draft finalized in 1969. iv. World Health Organization Method; "WHO Research Series No. 125, 1957, 28. e. Delivery Rate Determinatin. i. CSMA Method. (No special equipment). See "Aerosol Guide". Seventh Edition. 1981. ii. Sun Tube Method. Drawing & Part No. B-1261. iii. General Kinetics Apparatus GK-66-DR. 5245.00. Figure 8. Valve Delivery Rate Tester Apparatus custom built for Peterson/Puritan, Inc., accurate to four significant figures. It consists of a solenoid-operated can holder/ actuator, stop clock measuring to ± 0.001 second, solid state relay and operating push button switch. iv. Peterson/Puritan, Inc. Apparatus. Precision ±0.0006 gram/second. See Figure 8. f. Density Determination. i. CSMA Hydrometer Method. See "Aerosol Guide". Seventh Edition. 1981. ii. CSMA Pychnometer Method. See "Aerosol Guide". Seventh Edition. 1981, 53. iii. Graduated Pressure Tube Method. g. Device for Determining the "A-D" Dimension for Valve Dip Tube Depth. See' 'Aerosol Guide'' Seventh Edition, 1981. h. Device for Charging "Sepro Cans" and "Mira- flo" cans. i. Device for Determining Air Content in Aerosol Cans. i. Zahm-Nagel Apparatus. For carbon dioxide packs, only. ii. Perchlorethylene Absorbtion Tube apparatus. For fluorocarbons and hydrocarbons only. iii. Gas Chromatograph, with special pressure valve. j. Adaptors for Connecting Pressure Gauges and Charging Devices to Valves. Some testing devices are highly specific and are used on only one or two aerosol products. Such an apparatus is the Drag Tester, used to determine the slickness of textiles treated with starch or fabric finish sprays. A motorized pulley arrangement is used to pull a heated iron at 44 inches (1.12 m) per minute over freshly treated cloth. A coil spring attached to the iron gives the force necessary to overcome the frictional resistance of the cloth/iron interface. By adding certain silicones or other lubricants to the starch, readings as low as 14g can be obtained. \ Laboratory Techniques An experienced aerosol formulator always makes test units and samples in ways that reflect the production situation. One of the more important production limitations, for instance, is air removal from the filled container. Although refrigeration filling provides 90 to 95% air removal, this production method is cosdy, cumbersome and fast disappearing. Other ways to remove air involve vacuum crimping, sparging and Next Page
422 Previous Page c. Aerosol Spray Pattern Testing Devices. i. DuPont apparatus with rotating cut-out sector over pick-up surface. Surface modifications include: (a) Glass plate coated with magnesium oxide; photographed. (Dixon) (b) Paper disc coated with talc-plus-dye; photographed. (Root) (c) Absorbent paper, with dye added to test can. (Gunn-Smith & Piatt) (d) Paper treated with phenolphthalein or thymolphthalein; photographed. (Johnsen). ii. Calibrated glass plate held flat. Sprayed from a fixed distance, such as seven inches. For starch dispersions and detergent sprays. d. Particle Size Testing Devices. i. Battelle Institute "Cascade Impactor". ii. Malvern ST-1200 Analyser; Malvern Instrument Company. iii. BAMA Method. Draft finalized in 1969. iv. World Health Organization Method; "WHO Research Series No. 125, 1957, 28. e. Delivery Rate Determinatin. i. CSMA Method. (No special equipment). See "Aerosol Guide". Seventh Edition. 1981. ii. Sun Tube Method. Drawing & Part No. B-1261. iii. General Kinetics Apparatus GK-66-DR. 5245.00. Figure 8. Valve Delivery Rate Tester Apparatus custom built for Peterson/Puritan, Inc., accurate to four significant figures. It consists of a solenoid-operated can holder/ actuator, stop clock measuring to ± 0.001 second, solid state relay and operating push button switch. The Aerosol Handbook iv. Peterson/Puritan, Inc. Apparatus. Precision ±0.0006 gram/second. See Figure 8. f. Density Determination. i. CSMA Hydrometer Method. See "Aerosol Guide". Seventh Edition. 1981. ii. CSMA Pychnometer Method. See "Aerosol Guide". Seventh Edition. 1981, 53. iii. Graduated Pressure Tube Method. g. Device for Determining the "A-D" Dimension for Valve Dip Tube Depth. See' 'Aerosol Guide'' Seventh Edition, 1981. h. Device for Charging "Sepro Cans" and "Mira- flo" cans. i. Device for Determining Air Content in Aerosol Cans. i. Zahm-Nagel Apparatus. For carbon dioxide packs, only. ii. Perchlorethylene Absorbtion Tube apparatus. For fluorocarbons and hydrocarbons only. iii. Gas Chromatograph, with special pressure valve. j. Adaptors for Connecting Pressure Gauges and Charging Devices to Valves. Some testing devices are highly specific and are used on only one or two aerosol products. Such an apparatus is the Drag Tester, used to determine the slickness of textiles treated with starch or fabric finish sprays. A motorized pulley arrangement is used to pull a heated iron at 44 inches (1.12 m) per minute over freshly treated cloth. A coil spring attached to the iron gives the force necessary to overcome the frictional resistance of the cloth/iron interface. By adding certain silicones or other lubricants to the starch, readings as low as 14g can be obtained. \ Laboratory Techniques An experienced aerosol formulator always makes test units and samples in ways that reflect the production situation. One of the more important production limitations, for instance, is air removal from the filled container. Although refrigeration filling provides 90 to 95% air removal, this production method is cosdy, cumbersome and fast disappearing. Other ways to remove air involve vacuum crimping, sparging and
The Aerosol Laboratory 423 purging, none of which is particularly effective. An average vacuum crimper — either an independent unit, or a segment of an "under-the-cap" gasser — will pull only about a 16 " Hg° vacuum under all head space conditions. This amounts to about 54% air removal. With volatile products, even as little as a 10" Hg° vacuum may cause boiling, making it necessary to fall back to a lower figure. For water-based products with head space volumes not exceeding about 200 ml, vacuums up to 20 " Hg° (67% air removal) can be attained. Vacuum crimping equipment is not generally available for aluminum tubes, glass bottles or plastic bottles. In this case, air removal is done by means of purging. A condensable gas, such as P-12, is poured into the opening of containers just before the valve is attached. The gas stream may be measured or continuous, and in some cases liquid propellent is dripped into the container, where it volatilizes on contact with the concentrate. Purging ranges from 15% to 65% in effectiveness, under the usual production conditions. Liquid purging is more effective than gas purging. Sparging, where nitrogen or a similar inert gas is forced into the liquid under pressure, separating as it is filled into aerosol cans, is another form of purging. It is rarely better than 5 to 10% effective in removing air, and therefore is always used in conjunction with vacuum crimping or purging. Sparging serves to replace a minor portion of oxygen in the head space with nitrogen, in addition to displacing most dissolved oxygen from the concentrate, and has no effect upon the final can pressure. Perhaps the maximum amount of air removal on a production basis was accomplished during the filling of an acidic fruit juice concentrate where the presence of oxygen exerted a dramatic can corrosion effect. Testing showed that Organosol lined cans of good quality were stable up to one year if oxygen removal was better than 85%. A combination of 23" Hg° vacuum crimping, carbon dioxide purging and nitrogen sparging was used. As a result 87 to 92% of the original air was removed, judging from remaining oxygen. Zahm- Nagel results showed 15 to 20% non-condensables (oxygen plus nitrogen). Calculations showed the mixture was about 12% oxygen. The reason for production difficulties in achieving high performance vacuum crimps lies in the fact that the process of air removal becomes less efficient as more and more air is removed. More dwell time is required to provide a 23" Hg° vacuum crimp than an 18 " Hg° one, for instance. This is shown in Table I. The 29.92 " Hg° vacuum listed in the table is theoretical, since this would require a 100% efficient pump of infinite size. The 25.00 " Hg° vacuum is a practical upper limit for most industrial pumps. The figures for degree of evacuation would decrease if any sealing leaks were present near the container. In the laboratory, vacuum crimps of up to 25 " Hg° can be obtained readily, and in certain instances, all the way to 29 " Hg°. Purging can be done with air removals of 95 to 99%. Under these conditions, cans made in the laboratory will have lower pressures, lower delivery rates, a slightly coarser particle size and generally less corrosion than corresponding production units. As a secondary effect, they will give better results in any Flame Propagation or Closed Drum flammability tests. Since laboratory samples must represent production units, care must be taken to leave the proper amount of air. For vacuum crimping, this can be done by use of a throttling valve on the vacuum pump system. An accurate can pressure, compared against pressures of 99% purged and atmospherically crimped cans, should give a measure of air removal to within about ± 10%. The pressure increase due to air is generally between 13 and 21 psi. The higher figure is obtained when sizeable propellent volumes are pressure loaded into aerosol cans. Oml. 50 ml. 100 ml. 200 ml. 300 ml. 400 ml. 500 ml. Table 1 Crimping Efficiency as a Function of Air Withdrawal Volume of Air Removed From Can with 100 ml. Head Space Percentage of Original Air Remaining in Can At 29.92' % of Air Removed ' Hg° Vacuum Degree of Evacuation At 25.00" % of Air Removed ' Hg° Vacuum Degree of Evacuation 100 60.5 36.7 13.4 4.9 1.8 0.65 0 39.5 63.3 86.6 95.1 98.2 99.35 0" Hg° 12" Hg° 19" Hg° 25" Hg° 28.5" Hg° 29.4" Hg° 29.7" Hg° 0 32.9 52.7 72.3 79.4 82.0 83.0 0" Hg° 10"Hg° 16"Hg° 22" Hg° 23.7" Hg° 24.5" Hg° 24.8" Hg
424 The Aerosol Handbook Most laboratories maintain two sets of gauges for taking the pressure of aerosols. The so-called "Inspector's Gauge", costing about $56.00, is accurate to about ±0.5 psi. Most laboratories maintain a small stock of these gauges in the popular 60 psi and 160 psi dials, using them only where the work at hand requires such accuracy. They are used as "Master Gauges", for checking the accuracy of the less expensive, routine gauges which cost from about $5.00 to $20.00. These gauges are accurate to about ± 3 % of the dial face range. Careful handling and use of pressure gauges is a requirement for good laboratory practice. The pressure of an aerosol can be determined via a number of procedures, depending upon the accuracy desired. The usual method is to bring the container to a fixed reference temperature (70°F or 130°F in the United States, and 77°F or 131°F in Europe) and attach a pressure gauge to the valve. By actuating the valve the pressure is obtained. The units of measurement are pounds per square inch — gauge (psig) in the United States, and kilograms per square centimeter (kg/cm2) or kPa in Europe. A convenient cross reference is that 100 psig is almost exactly 7.00 kg/cm2 or 689.5 kPa. Every so often pressure data is given in terms of pounds per square inch — absolute (psia). These figures are obtained by adding the atmospheric pressure to the pressure gauge reading, in order to obtain the container pressure in reference to absolute vacuum condi- (Teimperature » 70°F.) PERCENT BY VOLUME OF LIQUID Figure 9. Graph of Air in Liquid and Vapor Phases Distribution of air between P-12/11 (50:50) liquid and vapor phases as a function of percentage by volume of liquid. tions. The average atmospheric pressure at sea level is 14.7 psi (103 kPa) whereas, within about 200 miles of Chicago it averages 14.3 psi (98.6 kPa) due to the prevailing altitude of about 750 feet. An aerosol can with an absolute pressure of 50 psia would provide a reading of 35.3 psig (243 kPa) in New York City and 35.7 psig (246 kPa) in Danville, Illinois, provided barometric readings were at their average levels. During stormy weather both gauge readings could drop as much as 0.5 psi (3.45 kPa). These considerations show the advantages of the psia scale where accurate results must be presented. It is almost impossible to prepare aerosols where the increase in pressure due to air is insignificant. CFC propellents carry dissolved air in amounts sufficient to elevate their pressure by 0.5 to 5.0 psi (3.45 to 34.5 kPa). In those rare instances when extremely accurate work is necessary, much of the dissolved air can be removed by allowing the pure propellent liquids to boil gently in a glass separatory funnel with a four foot (1.22 m) long piece of glass tubing corked into the top. After about a third of the liquid has boiled off, the propellent can be poured into aerosol cans through the bottom outlet of the funnel. Depending largely upon the method of preparation, the partial pressure of air in aerosol dispensers will vary between about 0.5 to 22.5 psig (3.45 to 155 kPa). The higher pressures are produced when the container is crimped atmospherically and then pressure loaded with a considerable volume of propellent. This is particularly important for low-pressure formulas in plain glass aerosols, where the pressure due to air may even exceed the gauge pressure of the propellent. When air is present in an aerosol container part of it remains in the head space and the rest dissolves in the liquid phase. The distribution ratio between the liquid and vapor phases is constant at equilibrium and is independent of the amount of air present. The ratio is determined by the volume fill in the container, the solubility of air in the liquid phase and the temperature of the dispenser. The distribution of air between liquid P-12/11 (50:50) and the head space above it can be seen in Figure 9. From the graph it is evident that the available air is divided evenly between the liquid and vapor phases when the container is 65 volume per cent filled. If an empty can is crimped atmospherically and then pressure loaded to a 65 volume per cent fill with P-12/11 (50:50), then one half of the original air will remain in
The Aerosol Laboratory 425 the 35 volume per cent head space, under 70°F conditions. From the formula: £± x Original Air Pressure (psia) = Final Air Pressure (psia) F2 Fi = Fraction of original air in head space F2 = Fraction of original head space the air pressure can be determined as: ^- x 14.7 psia =21.0 psia (145 kPa-abs.) 35% If, in the same example, the propellent is filled to 75 volume per cent, then 62% of the air will dissolve in the liquid phase and the air pressure in the head space works out to be 22.4 psia (154 kPa-abs.). If the air were to be insoluble in the liquid phase, as would be the case for mercury and a few other substances, the pressure of air in the 25 volume per cent head space would become 58.8 psia (405 kPa-abs.). Taking the pressure of an essentially air-free aerosol package is a simple matter, and almost any kind of a gauge system can be used. A non-prepressurized gauge will give the same result as a prepressurized one. But when the aerosol contains a fair amount of air, accurate pressures can be achieved only with prepressurized gauges. In this case a gauge is used which is fitted with a toggle valve and aerosol can valve adapter. The adapter is connected to an aerosol can of P-12 or other suitable propellent and the toggle valve opened to allow pressure to enter the Bourdon tube of the gauge. The valve is closed and the unit disconnected. Generally, the pressure of the sample aerosol container is known within reasonable limits. The toggle valve is cracked to allow slow escape of propellent vapor from the gauge until the upper limit of the probable pressure range of the sample unit is reached. The gauge system is then connected to the sample unit and the toggle valve opened. A more perfect pressure equilibrium is sometimes reached if the sample unit is shaken or jolted with the gauge open to it. This simple method is the one used most commonly in nearly all aerosol laboratories. Significant errors do not arise unless the maximum sample pressure is badly misjudged, or unless a large gauge system is used to check the pressure of a small sample unit with high air content. An alternate method, which has achieved some prominence is one in which three consecutive readings are taken on the same aerosol can, using non-prepres- surrized equipment. The true pressure of the sample is referred to as the "0th" pressure reading, obtained by backward extrapolation of the results. For instance, if the readings are 28, 27 and 26 psig, the original sample pressure is considered to be 29 psig. This method is more cumbersome than the prepressurized gauge method just described. One of the surest ways to harm a pressure gauge (short of dropping it) is to allow various aerosol residues to collect in the Bourdon tube so that its motion is distorted. Prepressurizing helps, but it is good practice to flush out gauge sysems using special aerosols containing either water or methylene chloride under pressure. Flushing should be done after every test or test series in order to prevent drying or corrosion. A seldom used alternate approach is to outfit the gauge with a protective diaphragm. These devices are fairly costly, running about $30.00, and are also bulky, with typical dimensions of 2 " x 2 " x 2 ". Diaphragm distortion can make gauge zero points tend to drift. Like the gauge, the protector unit must be flushed clean, or residues may build up around the diaphragm which will cause distortion of the pressure readings. Another primary measurement taken on aerosol cans is the valve delivery rate. In prescribed limits, it provides assurance that the product has about the right pressure, viscosity and density; and that the orifices of the valve are about the right size. Since delivery rates are affected by so many variables, the largest being the tolerance of valve orifice diameters, it is quite common for them to vary within a range of ± 15% from the target value. Since entrapped air increases the pressure, aerosols with significant amounts of air start out with higher delivery rates than normal. The delivery rate decreases moderately as the can is used up, unless the valve is of the vapor-tap variety. In this case, the delivery rate decreases rapidly, since the air is discharged direcdy from the head space, and more air boils slowly out of the solution to replace it. The delivery rate of air-free aerosols will also decrease as the container is used up, but very slowly, perhaps unnoticeably in many instances. This is due to propellent fractionation, which takes place when any
426 The Aerosol Handbook propellent is dissolved in a concentrate or in additional propellent. The more volatile propellent goes into the expanding head space preferentially, causing a pressure decrease. The delivery rate of an essentially full can of P-12/11 (50:50) will decrease about 8% from beginning to end. Air-free cans of pure, single propellents, or of such propellents over a concentrate in which they are immiscible, will give constant pressure readings and delivery rates throughout the life of the container. Most delivery rates are taken very informally. The container is temperature equilibrated to 70°F (80°F for insecticides) weighed, sprayed for exactly ten seconds and reweighed. The rate is usually expressed as grams per second, but some firms prefer grams per minute. Because of the large variations in delivery rate, it is generally poindess to determine individual readings wiui any better than the accuracy of ± 1 % or so, which this method provides. Various mechanical devices are available, but they are rarely used. They depress die valve button magnetically and measure seconds with an electrical timer connected to the solenoid. In at least one instance, such a device demonstrated a precision of ± 0.0006 gram per second. It served as a research tool for determination of high kinematic viscosities, extent of product/valve interactions and effect of varying force direction on valve button. Delivery rates can be a problem where three-phase systems, dispersions of solids and certain emulsion systems are involved. The first two tend to settle out, generally causing the delivery rate to increase from second to second. Some emulsions tend to hold gas bubbles in solution if shaken, causing a reduction in apparent delivery rate. The ten second delivery time is preferred over others. For one thing, it corresponds more closely to the average time of a consumer use. Also, at less than ten seconds, the accuracy of the time check is impaired. At longer than ten seconds, such things as product setding, cooling of the formula (especially with vapor tap units) and warming of the formula (from warm air, or from grasping the container) all act to create aberrations which affect accuracy adversely. Prior to taking pressures, delivery rates, flamma- bility studies or other measurements, the container must be equilibrated to a fixed temperature, usually 70°F (21.1°C). An error of 1°F (0.55°C) can easily cause errors of from 0.6 to 5.0% in pressure and delivery rate determinations. The larger errors are found with lower pressure formulations. The time required to bring the aerosol dispenser to the desired temperature is a function of a large number of factors: a. Magnitude of temperature change required. Longer times are needed for larger adjustments. b. Specific heat of the formula. Compositions with high specific heats, such as water-based types, change temperature more slowly. c. Viscosity of the formula. Compositions with higher viscosities resist heating or cooling, due to poor convection. d. Shape of the container. Compositions in squat cans change temperature more slowly than those in slim cans. e. Size of the container. Larger cans change temperature more sluggishly than smaller ones. f. Type of container: i. Metal cans conduct heat better than glass. Glass conducts better than plastic-coated glass. ii. Compartmented cans conduct heat very slowly, due to the insulating effect of the plastic bag and (especially) the exo-space between can and bag. "Sepro" cans change temperature more slowly than "Powr-flo" dispensers, since the bag is uiicker, has less contact with the can wall and surrounds the product completely, except for the valve cup. iii. Co-dispensing dispensers take longer to heat or cool, since the plastic bag or botde serves to insulate the Phase II inner solution. g. Fill in the container. A half-empty can will equilibrate faster than a full one. h. Agitation. An agitated can will equilibrate much more rapidly than a still can. Cans in agitated water baths equilibrate somewhat faster than cans held under quiet conditions. Aerosols are temperature equilibrated in several ways. Reference temperatures of 70°F (21.1°C) and 130°F (54.4°C) are those used most commonly for taking pressures, but the 70°F (21.1°C) figure is used for nearly all other standard tests. Two levels of accuracy have been established informally: routine and research. The routine procedures are used where only moderately accurate pressures or other test results are required. All methods use water as the heat transfer
The Aerosol Laboratory 427 medium, and in every case the final temperature of the water should be used as the reference temperature. The following procedures apply to low viscosity aerosols in standard metal cans: a. Routine procedures. i. Swirl cans in at least twenty times their weight of water for 5 to 10 minutes. ii. Immerse cans in at least twenty times their weight of water for 15 to 30 minutes. b. Research procedures. i. Immerse cans in a circulating or agitated constant temperature bath for 30 to 60 minutes. ii. Immerse cans in at least forty times their weight of water in an insulated tank for 60 to 90 minutes. For glass aerosols, use twice the suggested time periods. For plastic-coated glass aerosols, use three times the proposed times. For "Sepro" cans, use at least twelve hour immersion times. For formulas which contain carbon dioxide or nitrous oxide, cool the can to at least 25 °F ( - 14°C) below the reference temperature before immersion. Shake occasionally during equilibration to help excess gas escape from the liquid phase. Where pressures, delivery rates and certain other determinations are involved, test results can be converted to 70°F (21.1°C) conditions by applying experimentally derived correction factors. Storage tests represent an important phase of nearly all product evaluation programs. If an established product is revised in some minor fashion, such as a change in the percentages of inert ingredients or the substitution of a new perfume oil, storage testing can be abbreviated or even eliminated. However, on occasion, revisions which appeared to be minor have brought about disastrous consequences. Typical examples are: a. The addition of 10 ppm of tartrazine dye to an emulsion of kerosene and water caused so much corrosion, that the product was withdrawn. b. The replacement of 4% isobutane with P-12 caused can perforations in an aerosol oven cleaner within three months. c. The use of 96v% ethanol in place of anhydrous ethanol reduced the shelf life of a line of hair sprays from several years to nine months. d. The replacement of a neoprene gasket with a buna gasket in a "female" valve caused a routine window cleaner to exhibit "blow-by" in two weeks. e. The addition of sodium omadine to an aqueous dispersion at a level as low as 0.01 % caused severe lead solder reactions and formation of precipitated crystals that plugged valves. From this it follows that, if there is any doubt whatever about the effect of a change in the formula or dispenser, adequate storage testing should be undertaken. Over 99% of all aerosol storage tests are conducted at either room temperature or 100°F (37.8°C). (Room temperature is generally considered to fall within 68°F to 77°F or 20° to 25°C.) There is now general agreement that finished aerosols will be stored at temperatures between about 68°F to 100°F (20 to 38°C), during most of their inventory and service life. Short exposures down to 32°F (0°C) and up to 130°F (54.4°C) seem to have no effect upon most products. Feezing affects most starches and a few other aerosol water- based products, and the effects of such exposures should be looked at in the case of such items. A few marketers like to use 110°F (43.3°C) storage, and one can company checks test cans for a month at 130°F (54.4°C). The value of testing at temperatures over 100°F (37.8°C) is certainly questionable; quite often test results are obtained which are very misleading. Cyclic testing has been used, but it is time consuming to transfer cans from 130°F to 40°F (54.4° to 4.4°C) and back again every two days or so. This procedure is rarely used except under special circumstances, such as accelerated testing of crimped seals thought to be defective. Storage results obtained at temperatures between 120°F and 130°F (48.9° to 54.4°C) can often be subject to gross misinterpretation when attempts are made to relate such data to more reasonable storage conditions. Consider these four examples: a. A bug killer containing about 99% petroleum distillate, pressurized with carbon dioxide gave excellent storage results at 130°F (54.4°C) but caused rapid can perforation at room temperature. Analysis showed a moisture content of about 160 ppm of water. At lower temperatures, the water came out of solution and formed a few small droplets which were saturated with carbon dioxide and were therefore relatively acidic. In the absence of inhibitor or can linings, the droplets bored holes through the can. At 130°F (54.4°C) the corrosive action was so diffuse as to become negligible.
428 The Aerosol Handbook b. Sodium lauryl sulfate in certain dispersions attacks tinplate far more vigorously at room temperature than at 130°F (54.4°C). This led to serious field problems in at least two instances. c. Perfumes, sensitive pharmaceuticals and other chemicals can degrade rather quickly at 130°F (54.4°C), but are stable almost indefinitely at 70°F(21.1°C). d. Plastic bottles leak by permeation at rates which are exponential with temperature. Leakage will increase by a factor of up to 250 times when uncoated Celcon bottles are raised from 75°F to 120°F (23.9° to 48.9°C), depending on content. The examples cited illustrate the folly of using high temperature storage unless such storage tests are integrated into a balanced testing program which includes a preponderance of storage at room temperature and 100°F (37.8°C). The skilled aerosol chemist will usually glean a lot more data from storage tests than merely information concerning compatibility. The following should be collected, especially since the added time requirement is minimal: a. Live Storage Testing i. Rate of weight loss between actuation times. ii. Delivery rate for every actuation. iii. Visual examination of spray pattern for abnormalities. iv. Can retentions. v. Misc. effects, such as staining of the can dome, etc. b. Dead Storage Testing i. Cumulative weight loss, extending out until container sacrifice. ii. Pressure of containers about to be sacrificed. iii. Delivery rate of dispensers about to be sacrificed. iv. VI. pH value of units about to be examined. Examination of formula for containers about to be sacrificed. (Color, odor, sediment, trace metals, phase separation rate, etc.) Examination of container for signs of incompatibility. Most laboratories test from 6 to 12 containers per variable. Variables include a formula change, valve change, storage temperature [usually two: R.T. and 100°F (37.8°C)] and storage position (normally two: upright and inverted). For a given dispenser and formula, 24 to 48 units are tested. Some chemists prefer to make either 5 or 10 dispensers per variable, storing them in six-pack or twelve-pack cases where the extra space is used to contain bottles of concentrate and/or empty sealed cans, to be used as controls at the time when evaluations are to be made. Storage is generally for one year. Two year studies are sometimes made, but this is a very long time to have to wait in order to approve a product for container compatibility. The can companies almost never offer can warranties for periods longer than one year. Changes in the concentrate can sometimes provide a more sensitive measure of can corrosion than direct Table II Increase of Metal Ion Concentrations in a Starch Formulation Packed in 202 x 406 Lined Cans Up to One Year at 70°F and 100°F (21.1°C and 37.8°C). CAN SPECIFICATIONS / CV / 1019 .25 1020 .25 1019 .25 1019A .25 1020 .25 1060 .25 1061 .25 /I Single Single Single Single Single Single Double °0 / Co Yes Yes 2/98 Tin. 2/98 2/98 Tin. 2/98 2/98 Nl /4^PbS 70 0 70 0 100 0 100 0 100 0 100 0 100 0 0 0 0 0 0 0 0 CONCENTRATION OF LEAD TIAL n Fe .12 .12 .12 .12 .12 .12 .12 3MON" Pb 2.3 1.1 0.9 Sn 1.0 0.5 0.5 "HS Fe 0.68 0.68 0.46 TIN AND IRON PRESENT (IN PPM. 5 MONTHS Pb 2.3 0.2 Sn 1.0 0.5 Fe 0.68 0.10 6 MONTHS Pb 2.8 1.7 1.8 Sn 4.0 0.5 0.5 Fe 0.68 0.36 0.30 OF CONC.) 12 MONTHS Pb 4.0 .1 4.6 0.1 Sn 5.0 0.6 10. 1. Fe 0.52 0.54 0.80 0.60 Analyses for lead and iron are accurate to ±0.05 ppm. Analyses for tin are accurate to ±0.5 ppm.
The Aerosol Laboratory 429 examination of the container itself. Development of buff colors indicates solution of iron. Increases in pH may signify that metal is going into solution, with metal ions replacing hydrogen ions. Differences in emulsion stability, odor, solid residues and so forth also give clues to indicate corrosion. Direct determinations of iron, tin and lead are sometimes made. The data in Table II show metal ion build ups for a typical aerosol starch when tested in four can variables: The results of this analytical study show: a. A single lining is adequate; double linings affording no further protection. b. Use of a side seam stripe reduces lead and tin corrosion by about 50%. c. Iron concentration grows to about 0.6 to 0.8 ppm and levels off. d. The rate of tin corrosion is about ten times as fast with 2/98 solder as with pure tin solder. e. The metal corrosion rate is roughly 50% faster at 100°F (37.8°C) than at 70°F (21.1°C). f. The amount of tin which goes into solution does so at an increasing rate for non-striped cans, reaching 5 to 10 ppm at one year. This may cause organoleptic problems. The product was commercialized as Code 1060, which uses a single lined 0.25# ETP can, striped and 2/98 soldered. After about 15 months of field experience there have been almost no problems. (It has now been revised to a welded side seam can.) The weight loss figures determined during storage can be used to determine the extent to which the aerosol container should be overfilled; that is, the amount of fill over the labeled net weight. This figure is derived from a consideration of at least four factors: a. Can Retention (Average Experimental Figure, less Test Allowance if any) b. Filling Machine Tolerlance (Two-Sigma Basis) c. Weight Loss in Dead Storage (Two-sigma Basis) d. Contingency Overfill Average (To Account for Exceptionally Long or Hot Storage, etc.) Can retention is usually only a few grams, and if a test allowance is subtracted the factor gets down to only a gram or two. Viscous products would be an exception. The two-sigma filling machine tolerance should be determined on the basis of the machines destined to fill and gas the product, with figures based upon their known performance with similar products. The tolerance is determined by taking the square root of the sum of the squares of the individual machine tolerances. For instance, if the two-sigma tolerances for filler and gasser are established as ± 3.0 g each, the total two-sigma tolerance will be ±4.2 g. (Not ±6.0 g.) Dead storage weight loss figures are usually presented in terms of g per year, or ounces per year. They can be applied in this form if the marketer considers that better than 90% of the product will move off the retail shelf within one year. If the product is a fast seller, slow seller or seasonal seller, different dead storage times will have to be considered. An insecticide produced during February will be sold within eight months if it moves well in the market; otherwise it may take up to twenty months (two selling seasons) before being sold. A greater overage must be added to slow moving products to make sure the State Inspectors will not find lightweight cans and institute seizure proceedings. In many cases, a marketer may establish a minimum overage in order to provide a small cushion of safety to further insure against field problems. This is sometimes referred to as a contingency overfill, and helps to compensate for such things as: a. Time filler or gasser may be out of control before detection and correction. b. Bicyclic control pattern of most fillers and gassers. (Cycle over drift.) c. Imperfection of statistical treatment of variable factors. d. Effect of unforseeable storage conditions upon weight loss. i. Unusually long storage. ii. Unusually hot storage. e. Difference in rate of average weight loss between laboratory results and various production lots. As an example, consider the rather unusual insecticide formula for a flying insect killer on page 430. Suitable test packs were prepared for upright and inverted storage at 75°F and 100°F, using ARCo. valve variables identical except for choice of gasket material. In addition, 24 cans of each valve were prepared and tested for live storage performance on a two-day cycle basis. The results of the 75°F (23.9°C) weight loss storage tests are recorded in Tables III, IV and V.
430 The Aerosol Handbook Table HI Flying Insect Killer. Weight Loss After Actuation —Buna-N Gasket (Losses shown in grams) Can No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Average Two days .2083 .2184 .2154 .2149 .2285 .2566 .2443 .2217 .1924 .3141 .1952 .1924 .1852 .2198 .1705 .1607 .1769 .2155 .1945 .2028 .2347 .2221 .2049 .1847 .2114 Two days .1871 .1804 .2380 .2459 .2138 .2487 .2381 .2276 .2093 .3053 .1959 .1937 .1880 .2107 .1805 .1689 .1597 .2155 .1916 .2038 .2330 .2370 .2069 .2119 .2121 Two days .2072 .1547 .2155 .2093 .2023 .2258 .2030 .2020 .1919 .3007 .1755 .1856 .1822 .1843 .1807 .1596 .1725 .2015 .1769 .1801 .2195 .2173 .1915 .1862 .1969 Total 6 days .6026 .5535 .6689 .6701 .6446 .7311 .6854 .6513 .5936 .9200 .5666 .5717 .5554 .6148 .5317 .4892 .5091 .6325 .5630 .5867 .6872 .6764 .6033 .5828 .6205 Loss/Ye 36.6 33.6 40.6 40.7 39.1 44.4 41.6 39.5 36.0 55.9 34.4 34.7 33.7 37.3 32.3 29.7 30.9 38.4 34.2 35.6 41.7 41.1 36.6 35.4 37.7 Table IV Flying Insect Killer. Weight Loss After Actuation — Neoprene Gasket (Losses shown in grams.) Can No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Average Two Days .1745 .2076 .1946 .1769 .2065 .1674 .2112 .1605 .2248 .2200 .1950 .2412 .1969 .2289 .1582 .1968 .2042 .2877 .2091 .1898 .1915 .2196 .2261 .1868 .2036 Two Days .1691 .2105 .1740 .1795 .1858 .2254 .2217 .1460 .2330 .1844 .1243 .2385 .1848 .2268 .1615 .2178 .1930 .2007 .2059 .1729 .1709 .2227 .2417 .1802 .1905 Two Days .1712 .2033 .0751 .1552 .2028 .2220 .2063 .1358 .2195 .1633 .1981 .2087 .1705 .2279 .1517 .1872 .1823 .2083 .1969 .1784 .1450 .2065 .2318 .1644 .1841 Two Days .1698 .2267 .1670 .1703 .1858 .2365 .2203 .1386 .2264 .1784 .2279 .2121 .1607 .2371 .1517 .2114 .1786 .2213 .1912 .1668 .1444 .2129 .2345 .1593 .1929 Two Days .1176 .1835 .1260 .0934 .2143 .2129 .2113 .0924 .2159 .1147 .2050 .2126 .0918 .2260 .0853 .1836 .1258 .2051 .1190 .0932 .1225 .1420 .2115 .1145 .1550 Two Days .1710 .1875 .1825 .1868 .1954 .1832 .2310 .1471 .2356 .1808 .2215 .2215 .1619 .2306 .2535 .1785 .1829 .2347 .2036 .1617 .1397 .2159 .2321 .1885 .1970 Total 12 Days .9732 1.2191 .9191 .9621 1.1906 1.2474 1.3018 .9204 1.3552 1.0466 1.1718 1.3345 .9666 1.3773 .9619 1.1753 1.0668 1.3578 1.1257 .9628 .9140 1.2196 1.3777 .9337 1.1267 Loss/ Year* 29.5 37.0 27.9 29.2 36.1 37.9 39.5 24.9 41.1 31.8 35.6 40.5 29.3 41.8 29.2 35.7 32.4 41.2 34.2 29.2 27.7 37.0 41.8 30.2 34.25 'Highly extrapolated values. Used to show magnetude in more familiar frame of reference; e.g. gms./yr.
The Aerosol Laboratory 431 Formula 3 Flying Insect Killer 0.51% Vapona Insecticide; 99% Tech. 0.24% SBP-1382 Insecticide; 85% Tech. 0.05% Epichlorohydrin 0.15% Perfume 15.80% 1,1,1-Trichloroethane 63.25 % Methylene Chloride 20.00% Propellent Blend A70 50v% Isobutane A31 50v% Propane A108 Tables III and IV are informational only. They do not relate to the factors used to determine product overage. However, examination of the Buna-N valve gaskets following live storage showed that they had swelled and become softened to such an extent that the sharp corner of the stem orifice cut into many of them, tearing bits of rubber from the inner surface. This did not occur in the case of neoprene due to the toughness of the swelled elastomer. As a result of this finding, the Buna- N gaskets were eliminated from further consideration. Can retention was found to vary between 3.2 and 4.6 g, on four cans tested. The average was taken as 3.9g. The tolerance in the concentrate filler was considered to be ± 3.1 g on a two-sigma basis, from results with a related product. The tolerance for the "Under-the- Cap" gasser is stipulated as ± 2.0 ml by the manufacturer, when 550 ml cylinders are used. This converts to ± 1.1 g of A70 propellent. Table V Weight Loss Storage Tests Can Number 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Average: Range: Deviation (2 Weight Loss (Grams/year) Buna-N Valve Gasket Upright Storage 11.8 9.8 12.8 13.2 9.0 12.4 14.1 12.7 10.0 13.6 11.5 5.1 cr^) + Inverted Storage 16.3 14.1 14.4 15.8 13.0 10.9 15.5 13.8 14.7 15.1 14.4 5.4 3.4 Neoprene Valve Gasket Upright Storage 13.7 14.0 15.2 11.7 9.7 15.1 13.2 9.6 12.8 11.1 12.7 5.6 Inverted Storage 14.1 17.7 13.1 15.5 11.8 14.3 18.0 15.2 11.3 16.1 14.7 6.7 + 4.1 The contingency overfill was set at 2.0 g by the marketer. It was also decided that the product would have a maximum life of 20 months in channels of trade. The total overage is derived from the sum of the individual overages, plus the combined two-sigma tolerances: Ot = R-net + Sav. + C + V Ftol.2 + Gtol.2 + Stol.2 The terms may then be filled in from the Flying Insect Killer example, using a twenty month maximum dead storage plan. The individual factors become: Rnet Rnet R-NET R-NET Ftol. Ftol. Gjol. Gtol. Sav. Sav. Sav. C = Net Can Retention = Average Retention — Test Allowance = 3.9-3.5 = 0.4 g. = Concentrate Filler Tolerance = ±3.1 grams. = Propellent Gasser Tolerance - ±1-1 g- = Dead Storage Weight Loss for the stipulated time period. = 13.7 ±4.1 g per year x 1.67 = 22.8 ±6.8 g. = 2.0 g. so that the total overage is given by: Ot =0.4+22.8+2.0+ V3.12 + l.l2+6.82 0T=25.2+ V5T2" 0T = 32.8g. Using the same contingency, similar calculations can be used to show that an overfill of only 15.8 g is needed for an eight month dead storage time. Conversely, a 20.0 g overfill equates to a storage time of 11.1 months. An average of about 5% of the cans will be found slightly underweight if tested by the standard wet tare method at the end of the respective time periods. This is not sufficient cause for seizure by regulatory authorities. Product Use Tests It is not enough to design an aerosol that has good economics and the proper physical attributes of pressure, delivery rate, spray pattern, storage stability and so forth. It must also perform well. A window cleaner must clean without streaking and a room deodorant must provide a pleasing fragrance without nasal irritation. In many cases product testing can be a complicated business, requiring a good deal of special equipment.
432 The Aerosol Handbook For hair spray product testing, the following methods are suggested: a. Film Hardness (Sward Rocker Method). Films cast on a glass plate at 50 % RH and 70°F to 80°F (21.1° to 26.7°C) are examined for hardness at 1, 2, 3 and 4 hours. Satisfactory values are those in the 18 to 28 range. b. Drying Time. Product is sprayed five seconds on standard glass plate. Drying time is rated as the time when the film becomes dry to the touch. Most products are between 3.5 to 5.0 minutes. Shorter times are better. c. Film Clarity. Product is sprayed to make an even film on glass. After ten minutes for complete drying, examine for clarity. Repeat at one hour. d. High Humidity Curl Retention. Two gram swatches of 12 " (305 mm) Remi, Blue String, European brown hair, (De Meo Bros., 39 West 28th St., NYC.) are washed, well sprayed, curled and held at 140°F (60°C) for 30 minutes and then overnight at 50% RH and room temperature. Remove holding clip, so curl spirals downward. Attach to retention board and measure increase in length every 30 minutes at 90% RH and 70°F (21.1°C) for a period of three hours. Mean Per Cent Curl Retention should be about 30.0% over the test period, as determined by: b. Wet Cloth Drag Test. Subjective evaluation of ease of wet ironing phase. Iron should not stick, stretch or bind on cloth. c. Scorch Test. Pass iron, preheated to 300°F (150°C), across cloth ten times. Compare cloth to standards rated 0 to 10 for degree of yellowing or tanning. d. Ironing Odor. Rate odors arising during ironing, as, "Formalin Type", "Burnt", "Overly Sweet", "Pleasant", etc. e. Handle Test. Subjective evaluation of cloth feel after ironing. Consider scratchiness, abrasive character, smooth, full, slick, stiff, limber, wrinkle ease, etc. f. Brightener Test. Place square of ironed cloth in ultraviolet view- box. Examine for presence and evenness of brightener under long wavelength ultraviolet light. g. Sole Plate Test. Iron a 24" x 24 " (610 x 610 mm) section of cloth previously dipped into the starch concentrate and wrung out until an equal weight of concentrate remains. Examine the sole plate for presence of starch adhesion. h. Flaking Test. Proceed as in the sole plate test, but examine the Curl Retention (%) = L(fully extended)-L(after exposure) vino L(fully extended)-L(before exposure) e. Combing Test. A subjective evaluation of adhesion, flaking, snarling, gloss and general effect on combing characteristics of aerosol hair sprays on hair. For specific testing of spray starch and fabric finishes we suggest these methods: a. Dry Cloth Drag Test. Attach spring scale of about 100 gram capacity to standard iron. Spray and iron test fabric until dry. Attach string to scale and draw iron across fabric mechanically at about 44 inches (1.12 m) per minute, noting tension. Reading should be 15 to 20 gon 100% cotton. ironed cloth for detachable flakes of dried starch, as well as glossy spots. Use dark colored cotton, i. Soak-In Test. Spray test fabric until fully covered. Iron. Watch for rate of foam die-away. Iron should not push foam across to any extent. Furniture polishes are tested by comparison with controls, since this method gives the best results. The test substrate is cleaned with mineral spirits, divided, and the two or more sections polished, using one or two applications depending on the surface. Evaluation is begun five minutes after the last application. The following properties are rated on a scale of 0 to 5, with 5 considered excellent:
The Aerosol Laboratory 433 a. Ease of Rub-up to Maximum Gloss. (Made during applications.) b. Gloss. (Evaluated as depth of gloss.) c. Uniformity. (Examine for streaks, dry spots and general uniformity.) d. Film Clarity. (Look for clearness and sharpness of reflections.) e. Smear and Mar Resistance. (Check for smear or oiliness by making an "S" widi finger. Check for mar by hitting surface a glancing blow with the knuckles. Note degree of film damage.) f. Film Healing. (Observe length of time for smear and mar to disappear.) g. Rebuffability. (Observe ease and completeness of repairability when smears and mars are buffed with polishing cloth.) h. Cleaning. (Check removal of old polish and common soils, as beverage stains.) i. Water Spotting. (Wait two hours after application. Allow penny-sized water drops to remain on surface 5, 15, 30 and 60 minutes. Blot off. Check for presence and degree of film damage.) j. Gloss Retention. (Compare degree of gloss of new and old wax films.) k. Dust attraction. (Compare dust accumulation against control up to one week.) Personal deodorants, after-bath body sprays and similar products are tested as follows: a. Antibacterial Efficacy. (Several standard microbiological tests may be used.) b. Feel of Skin After Spraying. (Not wet or excessively oily.) c. Chill Factor. (Use Chilling Effects Machine, developed by Allied Chemical Corporation, to measure relative drop in surface temperature on spraying.) d. Odor. (Fragrance, level and duration. Possible nasal irritation.) For new aerosol items, special methods must be worked out. Whenever possible, the test method should bear a relation to consumer use conditions. Product Economics The aerosol formulator fights a constant battle to minimize the cost of his product, or to reduce the cost of an existing product. This is a potent tool for die contract filler in obtaining new business. To the marketer it means more profits, and often an expansion in sales volume. More money can be saved by revisions of formulas than by manipulations on cans and valves. Typical areas for study include: a. Replacement of high-priced perfume oils with less expensive ones. b. Replacement of high-priced solvents, oils, extenders or diluents with less costly counterparts. c. Addition of water to edianol or isopropanol formulas as a partial replacement for the alcohol while still retaining compatibility. d. Substitution of hydrocarbon propellents for fluorocarbon types whenever possible, and within limits dictated by flammability considerations. e. Use of lowest cost hydrocarbons, instead of isobutane. f. Replacement of costly active ingredients with less expensive ones. Most aerosol products now on the market can be rendered less expensive through the effects of a concerted research program. Quite often a single-lined can may be used instead of a double-lined container, or the lining on a valve cup may be eliminated by the addition of a trace of vapor-phase inhibitor to die formula. Sometimes the use of good vacuum crimping can reduce the corrosion potential of the formula to the point where less expensive packaging can be used. Every aerosol product category can be considered to have an optimum perfume cost, based on the price of the fragrance and the amount used. For disinfectant/deodorant sprays a $6.00 fragrance, used at about 0.10%, is best for fluorocarbon types, while a $5.00 oil, used at about 0.16%, appears best for hydrocarbon varieties. Up to about 0.25% of $5.00 to $7.00 perfume seems preferred for shaving creams, unless some special odor significance appears in die product advertising. An aerosol cologne will carry about 3 to 5% of a $12.00 fragrance. There are no hard and fast rules, of course, but if excessive perfume costs make a product less competitive, a lower priced perfume should be considered. The increasing scarcity of isopropyl myristate has now escalated die cost of diis lipophilic carrier to well over $1.00 per pound. Isopropyl palmitate, and odier esters have been recommended as replacements. Water may be added to various colognes, disinfectant/deodorants and odier products to reduce costs. In
434 The Aerosol Handbook some cases increases in product acceptability have resulted. The extra water is often needed to stay safely inside flammability limits. Perhaps the greatest potential for cost reduction is in the area of substituting hydrocarbon propellents for fluorocarbons. Nearly all U.S.A. antiperspirants used about 90% of approximately P-12/11 (35:65) until about 1977. By replacing this with hydrocarbon A31 at 75 to 80% a huge reduction in propellent cost was effected. Similarly, hair sprays are on die world market with 30 to 50% fiuoro- carbon propellent. The average U.S.A. hair spray now contains 20 to 25% hydrocarbon propellent — about A36. The effects of die increasing differences in price are being felt during 1982, and so it would be wise to start programs to determine the effect of replacing isobutane witih blends such as 16 v% propane and 84 v% n-butane. Similarly, A46 might be replaced with a mixture of about 34% propane and 66 v% n-butane. Extensive work on pressure, delivery rate, particle size, spray patterns and vapor-tape partitionment will have to be done in order to authenticate the new blends. Finally, die replacement of cosdy active materials provides an interesting area for cost reduction. Recendy a fabric finish was reformulated to use "Technical Grade" CMC materials instead of die more expensive "Standard Grade". The only significant difference was in salt content. In anodier instance, a series of insecticides was reformulated to use die syndietic pyrediroid SBP-1382 at 0.20% as a replacement for 0.20% pyredirins plus 1.00% piperonyl butoxide. The syndietic product was less cosdy dian die pyredirins, and required no synergist. The final factor in achieving maximum product economics is one often neglected during product development. The aerosol must be designed for production under high speed conditions. Any deviation adds cost. Special attributes, such as oversized valve buttons, aluminum cans, or multi-stage filling requirements, will always increase production costs by making die line run more slowly or by requiring additional people to accommodate die increased packaging requirements. By keeping all diese factors in mind, die aerosol chemist should be able to develop aerosols widi good consumer acceptance and good economics. Such products, will have die maximum chance for survival in today's competitive markets. Specialized Equipment for Aerosol Testing tr * •> *u Figure 10. Reed Pressure Burette Figure 10A. Burette by Aerosol Lab. Equip. Corp. Reed Valve Torque Tester This device, which measures die amount of force required to twist or rotate a valve cup on die bead of die can to which it has been crimped, consists of a hand- wheel diat holds a collet, a tee-bar wrench to lock die collet on die hub, and an adaptor connecting die hand- wheel to a torque wrench. The equipment is supplied packed in a box, widi a set of collets. It is used to detect poor crimps which might not be apparent on die basis of depth and diameter measurements. The device can be used on glass bottles as well as on metal cans. Available from W.H. Reed Co., Punta Gorda, FL at a price ranging from $459 to $629 depending on number and type of collets included. Pressure Burettes These devices are useful for a number of types of studies around die aerosol research and developmental laboratory: experimental filling of aerosol packs; exam-
The Aerosol Laboratory 435 ination of pressurized liquid systems; measurement of density, vapor pressure, etc.; determination of viscosity, surface tension, miscibility boundaries, etc. The burette handles a wide range of container sizes from 5 ml glass botdes to 20 oz (590 ml) 9 " (229 mm) tall cans. It accommodates two sizes of tubes: the 240 ml tube graduated in ml, or a 60 ml tube with 0.2 ml divisions. Available from W.H. Reed Co., Punta Gorda, FL at a price of $829 for die basic unit. The Reed burette is shown as Figure 10 on page 434. A burette by Aerosol Laboratory Equipment Corp., Walton, N.Y. is shown in Figure 10A page 434. The pressure filling burette is equipped with gas handling system and aerosol valve adapter, mounted on a stand. The 50 ml glass burette (within a Lucite protective cylinder) is charged with liquid propellent. The natural pressure is sometimes augmented by' 'topping off' with nitrogen, to facilitate flow. Alternately, the aerosol can and contents may be cooled. The adapter is connected to the can. The increase in gross weight is noted, since this is more precise man volumetric measurements off the burette scale. Several gassings and weighings may be needed to come to the exact desired propellent weight addition. Hydrostatic Bursting Unit for Aerosol Cans Specialized equipment for applying hydrostatic pressure to aerosol cans to determine susceptibility of the container to bursting or distortion is available. The unit is equipped widi a pressure gauge measuring up to 1,000 psi, and has a needle type can piercing coupler. Universal fitting valve caps are supplied. The device should be useful in testing the new anti-bursting, pressure-relief containers such as American Can Company's RVR container. All of them could be tested by the device as it is supplied, but the valve types would require the addition of a side-piercing ring. Available from Aerosol Laboratory Equipment Corp., Walton, NY. Can Puncturing Device A simple, inexpensive can puncturing device has been developed by the Freon Products Division of E.I. duPont de Nemours & Co. Inc., Wilmington, DE. It is small, easy to assemble, and the can to be punctured can be positioned in the equipment in the most convenient way. Cost is between $5.50 and $8.50 to make. In assembling the device, a piece of 1" x 2 " x J4 " steel is drilled and tapped for J4 " NPT straight thread in the center of a 1" x 2 " face. Two Aero-Seal M44 hose clamps hold the steel plate to the side of die can. The can is punctured by threading a "Fitzall" Can-O-Gas puncturing valve through the plate and into the can. The gasket on the valve provides the necessary seal. An alternate device, which is not quite as strong, can be made by bending the prongs on die clamps furnished with me Fitzall valve to a horizontal plane. The two opposed prongs are dien pressed into contact with the can by two Aero-Seal M22 hose clamps. The can is punctured by threading die puncturing valve dirough the can clamps in die normal manner. Valve Thickness Gauge (CS-100-70) A gauge for measuring the combined tiiickness of die valve cup and die flowed-in compound in an aerosol valve is available through the Chemical Specialties Mfrs. Assn., 1001 Connecticut Ave. NW, Washington, DC 20036. Aerosol Decrimper A Decrimper unit is offerd which makes it possible to readily remove die valve from an aerosol container and recover die contents for re-use. The container can dien be refilled and resealed if desired. The unit is capable of pulling die valves from 800-900 cans per hour, or inserting new valves in 400-500 cans or botdes per hour. Supplied by Aerosol Laboratory Equipment Corp., Walton, NY. 1 I i 'i I Figure 11. Aerosol One-Inch (25.4 mm) Valve De- Crimper, Showing a Second Adapter and Collet
436 The Aerosol Handbook Figure 12. Precisionaire Valve Tester Apparatus made by Sheffield Division of Bendix Corporation. Model B60103063. Measures air flow through a valve under fixed pressures by means of an air-float ball in a calibrated one foot (305 mm) glass tube. Valve Delivery Rate Tester This device measures air flow through a valve under fixed air pressure conditions. The valve is attached to the device for testing. Made by The Sheffield Corp. (A Division of Bendix Corp.) Dayton, Ohio, this piece of testing equipment is called The Sheffield "Compact" Precisionaire. Aerosol Spray Test Apparatus Equipment for determining the spray characteristics and other properties of aerosol products has been developed by Haarmann & Reimer GmbH, Holzmin- den, Germany. It is also useful in checking valve performance. The device measures such characteristics as spray pattern, spray rate, angle of spray cone, droplet size, quality of dose, functional control, and degree of evacuation. It can be pre-set to spray the contents of a container at selected time intervals, with spraying and pause periods being set on two relays. The standard unit is fitted with an actuating plunger for vertically actuated valves, and special plungers can be installed to actuate tilt-type valves. Where it is desired to carry out tests on a number of aerosol packs at one time, it is possible to connect several of the spray devices so they can be actuated by a single control unit. The unit is sold by Aerosol Service AG, Switzerland. Figure 14. Spring Force Tester Figure 13. Aerosol Spray Testing Apparatus Spring Force Tester for Aerosol Valves An instrument is offered for measuring the force and/or travel required to actuate an aerosol valve. It is useful in checking incoming valves received by the filling plant. It measures, not only the strength of the valve itself, but also the force required to actuate it, including spring pressure and the sealing effect of the gasket. It also measures the travel required to open the valve. Excessively low measurements will warn of the possibility of leakage, while valves that require a great deal of effort to actuate may cause difficulty in use. Supplied by Aerosol Service, Switzerland, at a price of about $652. Device for Measuring Crimping Force A dynamometer is offered for measuring the force exerted on the top an aerosol container when the valve is crimped on. The device is useful for checking when leakers of undetermined origin occur. By its use it is possible to determine if the cause of leaking may be insufficient force applied during crimping. The device measures the actual load applied to the gasket during crimping. A standard spring is held in a stationary
The Aerosol Laboratory 437 base, with a movable pan above the spring. A gauge measures the length of the spring, reading the amount by which this length is diminished during crimping of the valve. The value is read on the gauge in millimeters, which can be translated into kilograms of pressure applied to the can by referring to a conversion table. This equipment was developed in Italy by F.D.G. Aerosol Filling Equipment Co., Bologna, Italy. Available in the U.S.A. from Aerosol Laboratory Equipment Corp., Walton, NY. Meter for Checking Mechanical Stability of Aerosol Can Curl Because the stability of the curl of an aerosol container is an important factor in obtaining a tight seal of the package, a device has been developed for measuring mechanical stability of the curl. The sawed-off upper portion of an aero can is placed in the stand, with the opening downward. A punch is then lowered onto the inside of the curled neck and pressure applied similar to that which would be applied during crimping, causing the curl to deform. After the strain has become stabil- I Figure 15. Can Curl Meter I r ized, the impingement distance is measured by a meter. The unit is sold by Aerosol Service AG, Switzerland.
438 The Aerosol Handbook STANDARD AEROSOL CAN VALVE NOMENCLATURE C.S.M.A.. CAN VALVE COMPONENT NOMENCLATURE A. B STAUQARO (RECOMMENDED) ALTERNATE. ACTUATOR SPRAY HEAD BUTTON -|MOUNT^Q CUP MOUNTING COVER WOUUTKGv CUP GASKETl IFLOWED-1N GvASKEVi STEM BASKET 5EAL\MG\ O^ASKETT VALVE. SEAT STEM SF»R\KiQ BODV HOUSNQ SPRING, CUP SHELL C»f=> TUBE. OTHER TERMS SUGGESTED FOR STAMP AR.DVZ.AT\ON. A. ~ ACTUATOR ORIFVCE: ID~QODV ORlF\CE. IB~ STEM ORIFICE C~ VAPOR TAR OR\FlCE
QUALITY ASSURANCE 439 13 Quality Assurance is defined as "all those planned or systematic actions necessary to provide adequate confidence that a product or a service will satisfy given needs." It involves making sure that the quality is as it should be. This includes a continuing evaluation of adequacy and effectiveness with a view to having timely corrective measures and feedback initiated where necessary. In contrast, Quality Control is defined as "all those operational techniques and the activities which sustain a quality of product or service that will satisfy given needs; also the use of such techniques and activities." Further elaborations can be obtained from the ANSI/ASQC Standard A-3-1978. The most essential function of any quality assurance group is to conserve money for the company. This is done in several ways; for instance: a. By minimizing losses due to the production or sale of sub-standard merchandise. b. By minimizing losses due to production downtime. c. By minimizing over-filling losses of materials. d. By suggesting optimum filling procedures and techniques for specific products so that smooth production of high quality merchandise will result. A less obvious benefit is that a good quality assurance and control program enhances the corporate image, both internally and externally, so that better employees and additional customers will be attracted to the firm. For example, many marketers now sell "drug" products, such as aerosol antiperspirants, athlete's foot sprays, sun screens and other items, all of which must be filled under the FDA's Current Good Manufacturing Practices (CGMP) program. A well trained and staffed quality assurance group is essential in bringing a firm up to the many standards now required. A
440 The Aerosol Handbook number of contract fillers are unable to meet these criteria for record-keeping, plant cleanliness and sanitation, procedure development and so forth and are thus denied access to certain types of aerosol business. Increasingly, cosmetics and toiletries are being produced under what amounts to CGMP conditions, and the Cosmetics, Toiletries and Fragrances Association (CTFA) has recently petitioned the FDA to extend their formal CGMP requirements to these products as well. This could well happen during the next few years. Suppliers quickly learn that it is far better to provide a good quality grade of merchandise to quality conscious customers than to face a possible rejection. Starting about 1980 a number of contract fillers and marketers began to us the "Report Card" system for evaluating their suppliers. The report covered many aspects, such as pricing, meeting delivery schedules, customers service support, new innovations, frequency of sales contacts, and also (very importantly) the quality of the products provided. A supplier with a good report card might be able to look forward to enlarging his share of the customer's business, or to other benefits. In a general sense, the size and caliber of the quality effort will depend upon management's assessment of the importance of selling a quality product and the financial justification of maintaining the required degree of control. Organizational Relationships The quality control group can be integrated into the overall organization in a number of ways, some better than others. One common scheme is to make it one of the essential divisions of the technical department. Thus, a typical chain of command would be: Executive Management Technical Director Quality Assurance Director Quality Assurance Managers Quality Assurance Technicians The approach has the distinct advantage of maintaining the integrity of the technical department, so that technical people report to those who understand their problems, except perhaps at the highest level. A less favored approach is where the quality control department reports directly to executive management. This plan may have a divisive effect upon the technical and laboratory operations, partly resolved in some instances by the creation of two technical centers; one for research and the other for control. Where the expense of duplicate laboratories cannot be justified, various compensatory factors may be introduced. The Technical Director may be given "dotted-line authority" over certain technical aspects of the control program. Or he may be made responsible for those laboratory operations involving chemical analyses, recordkeeping, customer contacts and so forth, advising the Quality Control Manager of any results which might affect his sphere of operations. There is a growing tendency to place quality control under the direction of the General Manager. Since quality and quantity do not always go hand in hand, this sort of relationship sometimes generates internal problems. In any event, the special needs of the General Manager must be considered carefully. A quality control program made too stringent can turn in upon itself, resulting in excessive plant downtime, large quantities of rejected stock, and friction between employee factions. In most operations the General Manager will provide a special group of relatively lower-skill people who conduct production control operations under line supervisors. Ideally, every person in the company should consider himself quality oriented, acting constructively to improve control whenever possible. In practice, of course, this is rarely the case. Every organizational plan must take many factors into account, such as the size and orientation of the company, the absolute and relative capabilities of key individuals, and the location of these various people. The can companies usually have their management locations and research centers so completely separated from their plants that quality control operations fall under the Plant Managers with less difficulty than is usually the case. In certain small marketing concerns, particularly those that make outside purchases of finished products, quality control may come under the Marketing Director or the Director of Purchases. Many larger firms add special positions, such as Corporate Director of Quality Assurance, in order to strengthen certain control areas or to gain uniformity among their various manufacturing locations. Regardless of the organizational structure, it remains the exclusive responsibility of executive management to insure that the quality control program is always uniformly superimposed over the activities of the purchasing, manufacturing and marketing departments. They must also make it clear that quality activities are a serious consideration of the organization, otherwise
Quality Assurance 441 they will be quickly relegated to a subordinate position. Consistently satisfactory product quality will occur only when all levels of the organization are held equally responsible for the consequences of quality decisions, as well as for the consequences of technological and production decisions. One important aspect of organizational responsibility lies in the matter of the "quality control over-ride". Most concerns have had to develop routines for handling situations where a rejection (or, more rarely, an acceptance) of material is stipulated by the Quality Control Manager, in conflict with the views of others in the company. Many smaller concerns have plans that provide for an over-ride by specific individuals, such as the Technical Director, Plant Manager or Senior Marketing Executive. The President may ultimately be determinative. Some larger organizations divide the responsibility for an over-ride among the Division Heads of various sections of the company which might be affected by the release of sub-standard stock. As a rule, all Division Heads must agree to release; otherwise the merchandise remains rejected. Final disposition is then made by reinspection, rework or destruction. Scope of Quality Control Operations The quality control program should be applied to all raw materials as they enter the manufacturing plant, and should remain in effect until the finished goods are shipped out. More recent government regulations have made it highly desirable to generate a "trial of paperwork", by which all approvals, routings, dispositions and other data relating to lots of incoming merchandise can be traced through the various operations until release as finished stock. These are, admittedly, ideal circumstances. They are rarely attained. They can be carried out only if the quality control department has sufficient and qualified personnel, and receives the complete cooperation of other departments within the manufacturing and warehousing areas. When control operations fall short of the ideal, they begin to reflect outside influences to the extent that certain products will be controlled more effectively than other. Household products are less controlled than cosmetics; and aerosol foods are less stringently looked after than pressurized pharmaceuticals. Products that are more difficult to manufacture are better controlled; also those more susceptible to storage problems. In a sense this is risk insurance. Contract fillers find they can exercise better control over larger productions than small ones. They may be expected to assign extra control measures to the products of customers who themselves are more quality oriented; or who say they are. Certain marketers may have specifc areas within the control program which they regard as being far more important than the others. Quality control departments have had to develop an uncanny ability to detect these idiosyncrasies, adjusting their activities accordingly. Whenever sub-standard material is detected, the department must act immediately to promulgate pertinent information. They must notify all other departments, first by telephone and then by confirming memoranda. If a supplier is at fault he should be notified at once, preferably by telephone, followed by confirming letter and illustrative samples. Records should be maintained to cover losses such as production downtime, extra labor and amount of defective merchandise. These are especially valuable if financial restitution appears appropriate. The modern aerosol manufacturing plant is so complex and integrated that failure to report quality problems immediately can have serious consequences. Another major quality assurance area involves preventative activities. The department is expected to HOLD RELEASE REQUEST No. Date_ DESCRIPTION OF PRODUCT OR MATERIAL Quantity REASON FOR HOLD __^___^ REASON FOR RELEASE REQUEST^ REQUESTED BY ^^_ Date_ APPP0yAL_TO_RELEASE_0N_EXTRA0RLINARY_QUALITY_BASIS ACCEPTED DENIED SIGNED DATE R&D MANUFACTURING MARKETING COMMENTS DISPOSITION Note: All approvals are on a one-time basis only. Figure 1. Hold Release Report
442 The Aerosol Handbook detect and correct any problems which might lessen the probability of producing good finished merchandise. Ideally, they should participate in a program for "first in, first out" rotation of warehouse stocks. They should require segregation of like materials to minimize confusion and extra handling, and to help insure that improper stocks will not be inadvertently brought to the production lines for filling. Compounding facilities should be inspected to see that proper procedures and precautions are being observed. The department should have frequent supplier contacts, in order to review mutual problems and agree on corrective procedures. Certain more sophisticated control groups maintain a point system analysis of supplier quality, reporting cumulative data and any special remarks to each supplier monthly or every quarter. In this manner the supplier is made aware of how he measures up against his competition, and what elements of his manufacturing operation most urgently Your Company {fame QUALITY CONTROL" REJECTION REPORT Date Line 12 3 4 Shift A B C_ Product Size_ Cu s t ome r Empty Cans - Dented or Bad Litho: Supplier Filler ] Filled Cans - Before Gasser Crimps Filled Cans - After Gasser (Includes Rejects Separated by Packers) Gasser Bath Pa ck i ng E. Other Rejected Components (List part and quantity) Quality Control Inspector_ Figure 2. Rejection Report require correction. Even though the supplier's product may never have been actually rejected, poor performance on the point rating system may result in loss of business until his quality is brought up to parity. By far the most complex task of the quality control department is that of monitoring production line operations. They must collect, tabulate, analyze and interpret data that will ultimately lead to reduced losses and higher product uniformity. They are required to correct these operations when they are unsatisfactory, allowing them to run without interference when they are satisfactory. Most important, they must know the difference between these two conditions; and this can only be determined by statistical means unless gross deviations are involved. Development of filling machine control charts, for instance, challenges each machine operator to improve his work and gives him the assurance that his workmanship is being observed and recorded because of its importance. The data can also be used to determine the capability of the machine to meet certain requirements. This prevents time being wasted in an attempt to coax greater precision from the machine than it can deliver. The quality control department is expected to do a great deal of record keeping. This is especially the case where CGMP programs are maintained. Reports of nearly all their activities are kept on file in case of field problems, court litigation, government inquiries, customer requirements and so forth. Statistical data must be available from previous production operations in order to know if process quality is the same from one time to the next and to establish a consistent economic balance between production quality capabilities and market quality requirements. In addition to records, samples of key raw materials, batches and finshed aerosols are maintained for re-evaluation in the event of field problems. Storage should be within a temperature-controlled, limited-access area. Records should be held for a minimum of three years, and samples for a minimum of one year. It is vitally important that the quality assurance activity be extended beyond the routine acceptance or rejection of incoming component lots and the control of in-process activities. The information gained through these operations becomes of much greater value when calculated, recorded and fed back to those responsible for initiating and improving package design, function, testing and evaluation. Only then can a proper quality assurance interlock be established through all parts of the organization.
Quality Assurance 443 Establishment of a Quality Assurance Program At the core of any quality assurance program there are three considerations: a. What tests should be conducted? b. At what frequency? c. At what acceptance or rejection level? The approach to these questions varies widely, depending upon the size and capabilities of the department, and on the specific product to be controlled. Programs are often enlarged to conform to special situations, such as: a. Specific customer requirements that extend beyond normal control levels. b. Production where one or more components are only marginally acceptable. c. Production where experience shows the need for extra control. d. Production of new products — or on new filling lines. The size, diversity and acceptance levels of any control program are generally worked out by a Quality Control Engineer or similarly oriented person, utilizing general information and also specific data relating to the product being manufacturd. Quite frequently a conference is then held so that the program can be reviewed with production, research, marketing, process control and other departments in order to gain agreement in principle. Further inputs and refinements are nearly always applied to the program during these meetings. Many customers request conferences with their contract filler in order to review their proposed control programs, prior to productions. In some instances, where extra personnel must be added by the filler to handle requirements of an above-normal nature, the cost of these people must be added to the filler's service charge. Any quality control test must be meaningful. It must define or measure an attribute necessary to the functionality or appearance of the final package. Ideally it should be rapid and lead to a positive result. For this reason physical tests are run in preference to chemical tests, whenever possible. The size of the acceptance sampling program for incoming materials, batched material and final aerosol products may vary from 0% to 100%. It may fall into any of these five categories: a. No testing whatever. b. Spot-checking. c. Scientific sampling. d. Constant-percentage sampling. e. 100% testing. Occasionally components or chemicals are received which are not inspected but are sent directly to storage, processing or assembly. Such treatment is often reserved for situations where: a. The material is used for production almost immediately upon receipt. b. The commodity has a history of high quality. c. Reasonable deviations in quality will not adversely affect the final aerosol. d. A certified analysis sheet, or a certified control chart concerning the process is provided by the vendor. FtfPAM IN TWLlCAIf COKPAKY WWE SUPPLIERS RESPONSIBILITY D0«NTI«E •»•» TIM* C«»M*I L>H Tia* . 0*i#» •! Iw fli ill. PRODUCTION DEPARTMENT t QUALITY ASSURANCE OR LABORATORY IDENTIFICATION OP DEFECTIVE PART ' t if" M. .i»Ui_ -■■lltll- SHIPPING t. OFFICE USE r»iMf Figure 3. Supplier's Downtime Report
444 The Aerosol Handbook e. The material is not readily subject to meaningful testing. f. The control program cannot be extended to include the commodity without adversely affecting other, more vital, control areas. If the material turns out to be defective, this fact may not be known until batching or production is begun. Costs related to chemical losses, defective aerosols, production downtime and so forth can then work out to many times the cost of the defective material itself. Under these conditions, the supplier may willingly replace the defective material, but will often balk at picking up the other, much larger charges, feeling that the customer should have exercised a reasonable degree of inspection. These situations easily result in strained vendor-consumer relationships. Spot-checking of random shipments is a compromise measure which will theoretically stop some defective material from entering production, but not the rest. It gives an element of flexibility to the control program, inasmuch as this type checking is often done only when there is the time or talent to do so. Scientific sampling plans provide the best compromise between 100% sampling and no check. They have the virtue of distinguishing between critical and less critical characteristics, the risk level of making a wrong decision is known, and all material of the same classification is subjected to testing of similar discriminatory power. (The large lots are not discriminated against, nor are the small lots under-inspected.) Constant percentage sampling is used often, although its popularity is dwindling in favor of scientific sampling. The most notorious of these plans is the 10% sample from each lot of material. The risk of accepting defective material under this plan is less than under the no-check and spot-check plans, but greater than that under the scientific sampling program at the same overall workload. The greatest fault is that large lots are over-inspected, while small ones are under-inspected. The 100% sampling program is rarely undertaken because of the exorbitant cost. It is encountered where a component is known to exhibit low or marginal quality, where it is expensive, or where perfect functionality is essential. Metered spray valves are a good example. They are often subjected to an extra-charge 100% inspection by both the supplier and the customer. Unfortunately, the efficiency of any checking technique decreases as the number of checks is increased, so that 100% inspections are sufficiently conducive to sloppy inspection practices and the true inspection level rarely gets beyond 85 to 90%. The acceptance levels will vary according to the general concept of the plan and the nature of the defect. The tighter the plan is, the more costly it will be to implement, and these costs must be reconciled against the added benefits to be derived. Defects vary in their ability to create economic losses. A minor container defect affects only one package, but not to the extent of making it unsaleable. A major container defect that can be detected during production is not as critical as one that would pass through production and later cause trouble in the field, such as a latent leaker or loose solder defect. A defect in a particular chemical might be enough to ruin an entire batch, or, if not detected, might jeopardize thousands of finished aerosols. The more serious defects are naturally subject to reduced acceptance levels during sampling. Scientific (Statistical) Sampling Statistical sampling is necessary to get the most reliable data for the least expenditure of time and money. Data inputs must be accurate. The sampling must be truly random and the results from the testing program must be honest and accurate. The use of a statistically sound sampling program in no way enhances the value of sloppy or erroneous data. The first consideration in establishing the sampling plan is to determine the desired degree of discrimination between acceptable and reject materials. The most valuable tool for doing this is the "Operating Characteristic Curve", commonly called the O.C.Curve. This curve permits the evaluation of the efficiency of the sampling plan under varying conditions of incoming material and is an excellent way of illustrating the risks that are inherent in all sampling plans. Consider the O.C.Curve for a sampling plan which provides for a sample of ten pieces taken from a lot of one hundred pieces. If the sample contains zero or one defectives, the lot is accepted. If the sample contains two or more defectives, the lot is rejected. In symbol form this is written: Lot size: N = 100 Sample size n = 10 Acceptance number: c = 1 The O.C.Curve shows the probability of accepting a lot if it contains a certain percent of defectives. For instance, if the material was actually 10% defective, the
Quality Assurance 445 sampling plan would accept about 74% of the lots and reject the other 26%. For other levels of defective material the curve gives *hese results: Table I Percent Defectives vs. Probability of Acceptance (From Figure 4, O.C.C.) OPERATING CHARACTERISTIC CURVE % Defective 0 5 10 15 20 25 Probability of Acceptance 100% 93% 74% 54% 36% 23% This level of discrimination is not very satisfactory, so that the example points to the need for a more elaborate sampling program. For a sampling program to operate satisfactorily it must accept nearly all lots considered to be of "good quality" and reject nearly all lots which are worse than this. The use of the world neatly provides recognition of the risks involved in sampling. Sampling fluctuations will occasionally cause erroneous results, and consequently result in an erroneous decision. The usual sampling plan is set up arbitarily to accept at least 95% of the lots which are as good as, or better than, the standard for "good quality". Conversely, up to 5% of the lots may be sent back to the supplier as reject goods when they really do meet the "good quality" standard. This is sometimes known as "Supplier's Risk". The figure can be reduced if the supplier provides material of better quality than the standard for acceptance. The quantification of what is meant by "good quality" is an essential consideration, whenever acceptance sampling is applied. What percentage of defectives can be tolerated? There is no simple set of rules. Most decisions are based upon past experience and general guidelines. Many fillers are provided with manuals by their more quality conscious customers stipulating what acceptable quality levels (AQL) to use for particular situations. The marketer often regards the filler's plant as a simple extension of his own manufacturing facilities, and thus provides for the uniform control of his products without regard to location. The AQL may be defined as the percentage of defectives that will be tolerated before rejection of the lot. •8 0.20 0 10 20 30 40 Percentage of Defectives in Incoming Lots Figure 4. Operating Characteristic Curve Sometimes, for special purposes, AQL is regarded as the maximum permissible number of defectives per hundred units sampled. A converse term, RQL, or rejectable quality level, specifies a measure of rejectable quality. This is where the quality is so bad that acceptance would invite substantial difficulties, either in the production process or in the quality of the finished aerosols. RQL is usually two or three times as large as AQL. As the value for RQL approaches that of AQL, the sampling plan becomes more discriminatory and larger sample sizes are required. Because of the risks inherent in any sampling plan, sample fluctuations will sometimes result in acceptance of sub-standard material. This risk cannot be eliminated except by 100% inspection, but it can be limited to some specified percentage. It is often called "Customer's Risk", and is usually set at 10% of the lots examined. These four quality considerations: a. Acceptable Quality Level—AQL b. Rejectable Quality Level — RQL c. Supplier's Risk—normally 5% d. Customer's Risk—normally 10% can be integrated into an O.C. Curve to show the degree of discrimination of the sampling plan. Assuming AQL is 3% and RQL is 8%, a curve can be constructed.
446 The Aerosol Handbook 3% AQL 0 10I2030 40 Per cent of Defectives in Lots 8% RQL Figure 5. Operating Characteristic Curve The intersection of the AQL line and the 95% confidence level line (5% Supplier's Risk line) provides the top point as indicated. The bottom point lies at the intersection of the RQL line and the Customer's Risk line. Typical values can be taken off the graph in Table II. Because of the relative proximity of the AQL and RQL values, somewhat over 200 samples were required for this curve, yet the probability of risk remains relatively substantial. It is always well to take Table II Percent Defectives vs. Probability of Acceptance (From Figure 5, O.C.C.) c/< Defective 0 2 3 = AQL 4 5 6 7 8 = RQL 10 Probability of Ac 100% 99% 95% 81% 50% 27% 17% 10% 0% Table III Acceptable Quality Levels — Aerosols Defect Rating Critical Major Minor Cans 0.10 to 0.65 1.00 to 2.50 4.00 to 6.50 Valves 0.04 to 0.10 0.40 to 0.65 1.00 to 2.50 Covers 0.40 to 0.65 1.00 to 2.50 2.50 to 6.50 Final Product 0.40 to 0.65 1.00 to 4.00 6.50 to 10.0 as many samples as can be handled, especially in critical situations, and where the time consumed in examination is minimal. Rather than go through the tedious mechanics of developing charts for sampling plans, based upon O.C. Curves, A.O.Q. Curves (Averaging Outgoing Quality Curves) and other considerations, it is best to use plans already developed by experts. The most widely used plans are presented in MIL-STD-105D, published April 29, 1963. This document is offered for sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. (See chapter on Test Methods for text). The MIL-STD requires the selection of an AQL. This necessitates the classification of a particular characteristic as critical, major or minor. The acceptance level for critical defects is much smaller than that for major defects, and the figures for major defects are likewise much smaller than those for minor ones. The AQL also conforms to the relative quality available. For instance, recognizing that valve quality is much superior to can quality, acceptance levels for valves are made correspondingly tighter. Table III gives some typical ranges Critical defects are defined as those which render the aerosol unsaleable, unusable, hazardous or malfunctioning. Major defects are considered as those which render the aerosol materially detrimental for the intended application. Minor defects are those which do not render the unit unusable, but are objectionable if present in sufficent numbers. They are often defects in decoration. In some instances critical defects will be treated at different AQL levels, according to whether the defective unit will be detected and culled out during production. A smaller AQL will be applied to critically defective units which would not normally be caught on the production line.
Quality Assurance 447 Most industry standards for acceptance sampling follow the general concepts of MIL-STD-105D. Most programs are not particularly elaborate, and utilize the single sampling plan, at normal inspection levels, as shown in Table V. As an example, if a lot of 1500 pieces is received, to be inspected at an AQL of 1.5, the table dictates a sample size of 125 units, with an acceptance level of 5 defects and a rejection level of 6 defects. When a lot is rejected by a small margin, the usual procedure is to resample at either the same or an expanded level. This is done in the hope that an erroneous result was obtained through the statistical process and that further examination will prove the lot to be acceptable. For a proper treatment all the data should be collected together; e.g. an acceptance upon second sampling should not negate a rejection on the first. More formal techniques are available for double sampling and multiple sampling, and charts for these approaches are provided in the MIL-STD. The MIL- STD also takes note of past performance as a guide to the degree of discrimination to be used in the present. Provisions are made for tightened or reduced inspection, including continuance and switching criteria. Incoming Inspection of Cans Aerosol cans are usually delivered in palletized loads, held in by means of bands, corrugate sleeves or shrink- pack plastics. Any cans on outside rows which are dented or scuffed during shipment are usually discarded and exempted from sampling. Less frequently, cans may arrive in bulk-pack cases, master shippers or standard reshippers. When cans are found spilled in the truck or railroad boxcar it is customary to take Polaroid photographs of the situation, and then institute cleanup on a 100% visual inspection basis. Cases which are badly scraped or gouged may be expected to contain defective cans. Shrink-packed palletized loads are favored, due to visibility factors and the fact that the cans are delivered free of dust and dirt. Table IV Incoming Inspection Program — Cans Class Crit. A Crit. B. Crit. C. AQL 0.1% 0.25% 0.65% Sample 500 500 500 Ac. 1 3 7 Re. 2 4 8 Table IV, for the three critical categories, the tables for the major and minor categories and the descriptions which follow can be used to illustrate the features of a multi-classification inspection program for an incoming lot of 35,000 to 150,000 aerosol cans. Description: Can interior contains solder flash or pellets over 0.009 " across that are loose in the can. Any defect which makes the can inoperative or hazardous. Paneling resistance below vacuum specification. Can not within CSMA dimensional specifications on visual basis. Presence of significant corrosion, flux or dirt; inside or out. Absent or incomplete varnish top coat over litho. Presence of visual construction defects that might cause leakage of over 10 grams per year: a. Double seam cross-over or similar defect. b. Overly tight double seam, so that metal is fractured or weakened. (Evidenced by protruding d.s. compound, thin metal, or sharp edges.) c. Side seam must be properly bumped flat. d. One-inch opening should appear round and with specified (open or closed) bead, Class Major AQL 2.50% Sample 500 Ac. 21 Re. 22 Description: Any deviation from can specifications issued for purchase: a. Can has improper tinplate thickness. b. Can has incorrect decoration on dome or base. c. Can has wrong solder. d. Lot contains cans with alien lithography. Any visual defect that makes the can unfit for sale. a. Dome defects: Scuffs or scratches through to the metal. Dents longer than M> inch. Significant under-varnish marks or stains.
oo Table V MIL-STD-105D (Table 11-A) Single Sampling Plan for Normal Inspection Sample aize code letter Sample aize Acceptable Quality Levela (normal inspection) 0.010 Ac Re 0.015 Ac Re 0.025 Ac Re 0.040 Ac He 0 065 Ac Re 0.10 Ac Re 0.15 Ac Re 0.25 Ac Re 0*0 Ac Re 065 Ac Re 1.0 Ac Re 15 Ac Re 2.5 Ac Re 4.0 65 10 15 Ac Re Ac Re Ac Re Ac R< 25 Ac Re 40 65 100 150 250 400 450 1000 Ac Re Ac Re Ac Re Ac Re Ac Re Ac Re Ac Re Ac Re 13 20 32 50 80 125 200 315 500 800 1250 41 0 1 o 0 I o o £ I 1 2 2 3 1 2 2 3 3 4 2 3 3 4 5 6 3 4 5 6 7 8 5 6 7 8 10 II 7 8 10 11 14 15 10 11 14 15 21 22 14 15 21 22 30 31 21 22 30 31 44 45 30 31 44 45 «o4 0 I O O 1 2 1 2 2 3 1 2 2 3 3 4 2 3 3 4 5 6 3 4 5 6 7 8 5 6 7 8 10 11 7 8 10 11 14 15 10 II 14 15 21 22 14 15 21 22 0 I 0 1 o o o 1 2 -3- 1 2 2 3 1 2 2 3 3 4 2 3 3, 4 5 6 3 4 5 6 7 8 5 6 7 8 10 11 7 8 10 11 14 15 o- o 0 o o o 1 2 1 2 2 3 1 2 2 3 3 4 2 3 3 4 5 6 3 4 5 6 7 8 5 6 7 8 10 11 7 8 10 11 14 15 10 11 14 15 21 22 14 15 21 22 21 22 o 0 1 0 1 2000 0 1 o O o o 1 2 1 2 2 3 1 2 2 3 3 4 2 3 3 4 5 6 3 4 5 6 7 5 6 7 8 10 11 7 8 10 II 14 15 10 11 14 15 21 22 14 15 21 22 21 22 <V 1 2 2 3 3 4 5 6 7 8 10 11 14 15 21 22 10 11 14 15 21 22 14 15 21 22 21 22 o <-% 21 22 30 31 30 31 44 45 44 45 ^r> T^i»" m Uae firat sampling pi as below arrow. II aanple aire equnla, or exceeds, lot or batch aize, do 100 percent inspection ■^t**^* a* Uae first sampling plnn nbove arrow. Ac *> Acceptance number. Re at Rejection number. 3" CD > CD —% O cn O X 01 13 Q. O" O O
Quality Assurance 449 b. Body Defects: Scuffs or scratches through to the metal, and exceeding Vm " x 1" on principal panel or Vm " x 2 " on back or side panels. Dents longer than % inch. Under-varnish blush, marks or stains over 1 % of lithography area. Significant lithography defects. Too dark, too light (per acceptance standards), mis- registered, hazy or illegible printing, upside-down, smeared or with missing letters. Solder not properly wiped free of excess. Side seam unduly flattened and bowed inward. c. Base defects: Scuffs and scratches through to the metal. Dents causing double seam to be significantly out of round or to cause can to wobble on flat surface. (Such dents may also cause hot tank eversion.) Any spots of grease, oil, dirt or grime over J4 " x Vi " in cumulative size. Any can interior containing solder nodules lightly attached but 0.010" in diamater or greater. (If they can be abraded off the can wall with a rubber policeman, rubber eraser or toothbrush, they are considered to be lightly attached.) Class AQL Sample Ac. Re. Minor 6.50% 500 1 Description: Dome Defects: a. Scuffs and scratches not to cumulatively exceed Vs" x % ". b. Dents between J4 " and V% " long. c. Under varnish stains over % " x %" in cumulative area, but not over %" x % " in cumulative area. Body defects: a. Scuffs and scratches through to the metal, not exceeding %t" x 1 " on the principal panel or %t" x 2 " on the side or back panel, yet greater than one half these dimensions. b. Dents or distortions over J4 " long but less than Vi " long. c. Under varnish marking or staining greater than Vs" x )4 " in cumulative area. Base Defects: a. Seam scuffs or scratches Vm " to V32" wide and longer than 2". b. Minor dents in the double seam, insufficient to cause the can to wobble on a flat surface. c. Knock out punch marks or other indentations which might interfere slightly with coding. Any spots of grease, oil, dirt or grime over Vs" x % " in cumulative size, but under J4 " x J4 ". Any interior which contains firmly attached solder pellets which are 0.010 " in diameter or greater. Class AQL Sample Ac. Re. 50 1 Special (— ) Description: Diameter of one-inch opening is outside the CSMA range of 0.996" to 1.004 " as measured with B&S Intrimik or comparable instrument. 1 0 1 Special (— ) Description: Upon side seam tear-down, solder is found to be crystalline, to contain worm-holes, voids, or flux pockets which could lead to leakage. Tabs are found to be unlocked, mis-formed, mis- centered or show draw-back. Lapped areas are less than 90% soldered, indicating loss of strength. Special (-) 10 (Function of degree) Description: Upon one minute immersion in a solution of 20% copper (II) sulfate in 2% sulfuric acid, enameled segments show significant deposition of copper metal, indicating absence of lining. 10 0 1 Special (—) Description: Measurement of total height and total diameter give results outside CSMA prescribed ranges.
450 The Aerosol Handbook - is The ' 'Special Test'' category was developed because of the need to do at least some testing where the nature of the test was time consuming to the degree that the precepts of MIL-STD-105D could not be reasonably followed. Other special tests may be undertaken according to special circumstances. Typical examples are: Figure 6. Micrometer for "G" Dimension A key dimension for the control of can curl geometry is the "G" dimension, measured at an inclination of 20° with the horizontal plane of the can bead with a barrel-type micrometer. This instrument is made by the LS. Starrett Co., Athol. MA as a special order item. \ / 0 » /^ «D I '3 ■** * it Figure 7. Gauge for Baseweight of Metal Made by Precision Material Company (Spring Valley, NY), this gauge reads to ± 0.0001", with a range of 0 to 0.0500 * and may be used for measuring cut sections of tinplate, aluminum or other materials. Various anvils are available to accommodate soft or curved items. **^ * Figure 8. Gauge for Height of Valve Cup The gauge positions the thin foot-like projection at the floor of the valve mounting cup so that the micrometer anvil is centered over the stem or stem hole, depending on valve type. If a stem is encountered, it slips conveniently into a verticle hole in the anvil. The gauge reads pedestal height to about ±0.0005" with a range to 0.500" and is made by Mitutoyo of Japan. It is available from the Bruwiler Precise Sales Company, Los Angeles, CA. a. Weight studies. Done to rapidly establish plate thickness. (Check with can supplier.) b. Solder analysis. Done to assure use of high- strength solders for high-pressure or critical packaging operations. c. Conductivity testing. Done to assure adequate metal coverage for spray-lined cans. Use Wilkens- Anderson (WACO Enamel Rater or equivalent.) d. Microscopic analysis. Done to detect enamel coverage at fillet area. e. Metal thickness studies. Done with ball and anvil dial micrometers or similar instruments to determine baseweights. f. Alcoholic fast flush and filtration. Done to determine degree of lint, corrugate fibers, loose flux, metal and other trash in aerosol cans. g. Determination of can bead 20° crimping diameter. Done with CSMA barrel type micrometer or comparable European instruments suitably corrected. To determine suitability of bead to seal onto valve with proper crimp. Low readings indicate need for shallower crimp depth. Variable readings indicate possible seepage. h. Pneumatic pressure test. Rare. Done to determine resistance to distortion or burst; normally by connecting carbon dioxide into can which is sealed with ARC Model LA-10 or comparable valve. Pressure is increased using a pressure regulation valve, holding can in a safety enclosure. Used for "Specification 2P" and "Specification 2Q_" can studies. The alternate liquistatic test is now officially suggested by the CSMA because of greater simplicity and safety, i. Leakage Test. Done for suspicious cans, to determine if product seepage might occur in storage. Attach valve and gas with a few grams of A-31, then hold unit under warm water and observe for bubbles. j. Can Lining Tests. Done to distinguish between single and double rollercoat systems, for presence of side seam stripe, and so forth. Vinyl topcoats
Quality Assurance 451 are detected by spotting with methylene chloride, where they dissolve to give a sticky solution. Rub- off exposes base coat, if present. Certain products cause the side seam stripe to slough off and cause valve clogging. In such instances, presence of the stripe constitutes a critical defect with an AQL of 0.1%. k. Exterior Lacquer Test. Done to establish presence of clear lacquer on ends. Check using acid copper sulfate solution, antimony chloride solution, or by making a % " scratch and observing for presence of lacquer curlecue with 7X to 20X magnification. Although the classification, description and interpretation of this ensemble of standard and special tests may appear rather rigorous, the program is currently being carried out for a number of larger marketers. Certain aspects of the test series may be of more interest to certain marketers than others, depending upon the particular product and other circumstances. Incoming Inspection of Plain and Plastic-Jacketed Glass Bottles Aerosol bottles are usually delivered in master cases holding from about 48 to several hundred units. Inner dividers and layer cards are provided to minimize abrasions during transport. Cases must be marked with complete information, such as lot number, content identity, customer's part number and so forth. Table VI and the accompanying descriptions can be used to illustrate the features of a multi-classification program for an incoming lot of 10,000 to 35,000 aerosol bottles. Table VI Incoming Inspection Program—Bottles Class AQJ. Sample Ac. Re. Crit.A 0.15% 315 1 Description: Bottle finish is for other than stipulated valve. Clear coated bottles are deficient in ultra-violet cut-off. 315 16 Crit.B 0.65% Description: Botde not within dimensional specifications, on visual basis. Presence of significant grease, dirt or grime; inside or out. W "tiurreM HI n ^ O n M * M M 40 Figure 9. Custom Made Valve Stem Height Tester with Dial Micrometer Readout Figure 10. Measuring Crimp Diameter German-made dial micrometer that can be used to determine crimp diameter or other inside measurements up to 2.000 " (50.7 mm). It is sold in the USA by the National Gage and Tool Co., Glendale, CA. Figure 11. Gauges for Crimp Measurements Federal Products Corporation Crimp Diameter Gauge Model 149P-611 and Crimp Depth Gauge Model 444P-161-R4, with related gauge blocks, used for the determination of one-inch valve crimping dimensions. The firm is located in Providence, Rl.
452 The Aerosol Handbook >« (V> Figure 12. Quicktest Crimp Micrometer The gauge on the left is the Kroplin "Quicktest" dial micrometer, Model S-1538 for measuring crimp depth. Extra 1/16 "or 2/32 "steel balls are available to provide for wear of this part. The larger device is their Model S-1180 for measuring crimp diameter. The toe sections can be screwed outward to allow for wear. Both gauges are very delicate and cannot be mishandled. Available from various sources in the USA, including Alpha Gage & Machine Tool Co., Downers Grove, IL. Absence of vent holes in PVP or Lamisol jackets. Roughness, chipping or other defects in finish area that could lead to leakage of over 10 grams per year. Presence of rockers or leaners. Lot contains bottles with alien silk-screening, where design is sufficiently close to standard as to require 100% inspection. Major 1.50% 315 10 11 Any deviation from specifications issued for purchase. Significant defects in glass—air bubbles, aberrations, strain refractions, cracks or stars. Significant defects in jacket—uneven coating, roughened areas, incorrect texture, surface flaws such as unfused resin, air holes, stars, bubbles, ripples, sags, barberpoling, wash- boarding or occlusions of foreign material. Significant defects in jacket color, color uniformity and decoration. Incomplete silk screening, fuzzy areas, lack of definition, missing or broken letters and smears. Insufficient jacket weight. Lack of adhesion on bonded jackets. Insufficient tensile strength — standard tester. Improper registration. Drop testing program shows defects. Improper registration. Drop testing program shows defects. Scratches on plain or enameled plain glass surface. One or more slits absent, or one or more holes, incompletely punched through the jacket, so that, upon dropping and bottle fragmentation, the release of gas may be so slow that the coefficient of elasticity (4.5 to 5.5) of the plastic will be exceeded and the inflated jacket will burst. High or low necks. Finish flat not horizontal, so that crimping integrity is reduced. Class AQL Sample Ac. Re. 315 21 22 Minor 4.00% Description: Insignificant defects in glass and/or jacket, of the varieties listed above. Broken bottles. Minor dirt on exterior only. Class AQL Sample Ac. Re. 16 1 Special — Description: Botde bursts under application of 150 psig pneumatic pressure for 15 second dwell time. — 1 0 1 Description: Heaviest bottle out of 24 checked for weight, fails to safely contain maximum (two-sigma) fill of product at 130°F. 1 0 1 Description: Gross discoloration of plastic occurs when jacket is exposed to proposed product, where exposure time is one hour and recovery period is 24 hours. — 16 12 Description: Silk screening can be dislodged from glass with fingernail, or from jacket by hard rubbing.
Quality Assurance 453 Under the "Special Test" category are others which are relatively time consuming and are therefore undertaken only when circumstances appear to warrant the added work. Some other special tests are: a. Adhesive Studies. Done to establish suitability of P5, P8 and other label adhesives upon the plastic surface, or of other vinyl adhesives for label attachment to the glass surface. Use of silicones and other surface treatment agents sometimes causes interference. b. Alcoholic fast flush and filtration. Done to establish presence and degree of lint, fibres and other contaminants. c. Glass Analysis. To differentiate between types. To verify use of Type 1 borosilicate for injectables. This program of tests may be varied according to specific requirements and constraints. In some instances, since the routine is simpler for plain glass, a larger sample size is withdrawn from the lot under study, thus improving the level of discrimination. Examination of all-plastic bottles; e.g. Celcon types; will follow the general concepts advanced for glass bot- des. Only one marketer is deeply into this field at this time, so a special treatment is not justifiable. Incoming Inspection of One-Inch Cup Valves Aerosol can valves are nearly always delivered in heavy corrugate cases containing from 1500 to 3000 pieces each. One panel carries printed data relating to the lot number, case number, quantity, general specifications, customer's part number, date of manufacture and so forth. It is desirable to pack the valves in an inner polyethylene bag, to protect them from adverse conditions of humidity, dust, lint, fiber pick-up and other contaminants. The valve is by far the most intricate part of any aerosol. The valve makes the aerosol a device, rather than (simply) a product in a container. The valve has seven or eight parts, all of which must be fitted together with accuracies of from ± 0.0002" to ± 0.0050" in order for the finished unit to function properly. It is a tribute to the valve manufacturers that they have made their product so reliable, at least partly due to the rigorous programs of quality assurance which they have developed and use religiously. Because the valve is such a vital part of the total aerosol package, where almost any "little" thing that goes wrong can lead to disaster, AQL levels are quite Figure 13. Gauge for Double Seam Height L.S. Starrett Company micrometer for measuring total double seam height and also body hook height, modified by Continental Can Company, Inc. Design No. G-37-1C. Range: 0 to 0.500" in 0.001" divisions on the barrel. i^«"' Figure 14. "Go/No-Go" Stem Height Gauges Plastic gauges supplied by the Seaquist Valve Company as used to control the height of the valve stem over the top plane of the mounting cup to facilitate correct adaptation to foam spouts and spray- dome fitments. Figure 15. CSAAA Gauge for "A-D" Dimension An aluminum gauge block is fitted with an accurately positioned 1 steel rule, measuring from 0 to 8 3/4". To determine the A-D Dimen- 1 sion, insert the valve cup into the left end of the device and read the position of the end of the dip tube on the ruler. Figure 16. Oditest Gauge for Can Bead This gauge is used to determine the contact height of Form Z (tinplate) and Form Y (aluminum) can curls, according to FEA (Specification DIN-55-500. It is made by H.C. Kroplin, Gmbh., Schluchtern, West Germany. Shown with standard 4.25 mm gauge block.
454 The Aerosol Handbook often tightened during incoming inspections. In some cases the AQL levels are left about the same as for cans, but the acceptance level is reduced by changing from MIL-STD-105D Normal Inspection to MIL-STD- 105D Tightened Inspection (Table IIB). While this is not in harmony with the concepts of tightened inspection, the modification serves the intended purpose by making the program 20% more critical. Table VII can be used to define the essentials of a multiple classification incoming inspection program designed to check a lot of 35,000 to 150,000 valves. Table VII Incoming Inspection Program — Valves Class AQL Class AQL Sample Ac. Re. 500 1 Critical 0.1 % Description: Any defect that will make the valve inoperative or cause the finished product to be unsaleable. Any valve which leaks — flowrater tester. Any valve which will not shut off—flowrater tester. Any valve which will not spray — flowrater tester. Missing component. Incorrect component. Missing or broken insert in actuator. Kinked, jammed or short spring. Gasket of improper composition, improper size or double gasket. Cracked, split or broken valve body. Loose diptube — 2.0 lb minimum pull force. Diptube split, stress cracked, overly brittle, kinked (if polypropylene or nylon), or attached in any fashion which allows undesired vapor access into valve system from headspace. Lack of specified vapor-tap orifice, if any. Improper weight, thickness range or coverage of D&D Flowed-In gasket compound. Dip tube more than Vi " shorter than specification. Split button or spout. Valve badly cocked or distorted in cup. Components produced from incorrect materials. Sample Ac. Re. 500 8 Major 0.65 Description: Substantial grime, oil, dirt or grease within cup or an assembly. Any rusting on cup. Contamination, mold, dirt or flash inside valve. Incorrect assembly; e.g. dip tube not fully slipped into or over tailpiece. Hard kinks in polyethylene dip tubes that might give trouble in automatic valve inserter unit. Dip tube more than Vt " too long; or between V\ " and Vi " too short. Spray rate significantly different from spec- ficiation; usually over 20% from average. Flowrater tester, with suspicious valves tested with actual formula and then torn down for further inspection. Button is incorrect color. Damaged mounting cup. Mounting cup not epon lined, or not epon coated outside, if specified. Directional dot missing, or 180° misoriented. (May not apply if button is attached, as received.) Loose actuators— 1.0 lb. minimum pull force. Class AQL Sample Ac. Re. 500 14 15 Minor 1.50 Description: Excessive, non-critical flashing on plastic pieces. Minor amounts of dirt, grime and grease on valve. Directional dot missing, or 180° misoriented, where button is attached. Excess marking ink on cup. Directional dot misoriented over 30°, where button is not received attached. Dip tube is outside specification range by more than V32 ", but less then %2". Determined using CSMA Dip Tube Depth Tester. Lack of mounting cup dimples, where specified, and vice versa.
Quality Assurance 455 Dip tube partly folded inward against tailpiece so that stress cracking might ultimately develop. Excessive scratching of open or Organosol lined mounting cups. Mounting cup has improper skirt length, where such defect interferes with reliability of attachment of specified cover or spray dome. Class AQL Sample Ac. Re. Special — 10 12 Description: Gasket i.d. Where a multiplicity of gasket inside diameters is available, as for "female- type" valves, examine gaskets against low power microscope reticule to determine hole size. Compare with chart of standard ranges. — 10 0 1 Description: Insert cups into 0.996" i.d. "go/no-go" gauge block. All cups must fit with moderate pressure. — 10 0 1 Description: For aluminum mounting cups only, prepare aerosols, using standard crimp with rounded collet tines. Gas with a few grams of P-12 and check under warm water for fracture leakage at crimp indentations. — 20 12 Description: Dip tube Curvature. Insert valves into testing jig to determine distance from end of diptube to extension of major axis of valve. Should be at least one inch per six inches for all capillary and standard dip tube diameters. — 10 0 1 Description: Using finger pressure, try to twist housing to test stake tightness. Compare results to standards, since some valves can be twisted or popped out of cup with only moderate force. Other special tests may be conducted as background or circumstances warrent. Examples of such tests are: a. Blow-by Study. Done principally for "female- type" valves. Prepare desired aerosol. Spray. Allow 24 hours for dimensional equilibration and respray. If product oozes or sprays up from gasket-to-button stem interface, valve is defective. b. Properly Plasticized Dip tubes. Immerse dip tubes overnite in p-nonylphenoxy-(EtO)9 -ethanol or comparable non-ionic surfactant. Withdraw, flush and check for splits. Other special tests are required for hermetically sealed valves, metering valves, valves with large diameter dip tubes, double dip tubes, "SA" attachments, codispensing designs and so forth. Glass bottle type valves are checked routinely, except that the mounting cup is now an aluminum or steel ferrule with various finishes. Ferrule skirt length varies according to whether the finished pack involves an aluminum or stainless steel tube, a plain glass bottle, an all-plastic bottle or a glass bottle with plastic jacket. Special tests are often applied to the larger sealing gasket to assure organoleptic compatibility with the product. Such gaskets are often made of special grades of buna rubber, are hot-washed with methanol, may be offered as low- carbon whites, using a titanium dioxide filler, or may contain special plasticizers. Incoming Paper or Paper-Backed Foil Labels Labels should be delivered in bundles of 500 to 1000 pieces, preferably wrapped in foil or moisture-resistant heavy paper. Each bundle should be identified as to contents, either by a specimen label or marking. Bundles should be packed in heavy corrugate or wood cases, so that dog-ears are avoided on label corners. Many labels have a strong tendency to react to humidity upon opening the bundle, curling along the grain. After sampling, bundles should be reclosed and taped shut. Data relating to lot number, supplier identity, number of labels, date of manufacture, customer's part number and so forth should appear on each case. Table VIII may be used to define a program for the incoming inspection of a lot of 10,000 to 35,000 labels. In some instances a new, critical or dubious batch of labels will be tested by attachment to warm cans under production conditions. Although the use of defective labels does not ruin the final product, rework, production downtime and excess label losses can be quite expensive. Certain conditions, such as edge wrinkling, cannot be corrected except by ordering a new lot of labels with improved sizing.
456 The Aerosol Handbook Table VIII Incoming Inspection Program — Labels Class AQL Sample Ac. Re. Critical 0.65% 315 5 6 Description Printing significantly misregistered. Lap margin along incorrect edge. Printing blurry, indistinct or significantly incorrect. Printing is of improper color or shade, compared with standards for acceptance. Key printing is missing; such as E.P.A. REG. No. The label is taller than the average can height between double seams, less V32". (CSMA Dimension F.) More than Vi6" of lap area is revealed upon simulated attachment to specified can. Major 1.50% 315 10 11 Description: When label edge is wetted with lap paste gross horizontal wrinkling occurs. Carry through designs fail to come together within Vie". Colors smear when rubbed with moist fingers, indicating absence of varnish top coat. Label stock exceeds 70# in thickness. Label stock is sufficiently translucent to show pick-up glue stains. Double printing or ghost printing is present. Label is shorter than average can height between double seams, less % ". Top and bottom edge chamfers are missing, where specified. Special — 1 0 1 Description: New label designs which do not conform to government regulations for printing, placement, precautions, spacing, type size and so forth. Minor 6.5% 315% 21 22 Description: Excessive blocking between labels, which could give trouble in labeling operation. Embossing or debossing does not match printing. Labels are excessively dog-eared, bruised, water-marked or wrinkled. — 10 12 Description: Grain of paper does not run as per specification. Wet tube test. Wet label back and it will form a tube running in the direction of the grain. Incoming Inspection of Overcaps In these days of increasing packaging sophistication, overcaps may be made of steel, brass, aluminum or various plastics. They come in sizes from those that fit over 13 mm ferrules to those that cover 300-diameter cans. Overcaps come in cases which contain from several hundred to several thousand pieces, depending upon size. In some instances the fitment serves not only as an overcap protective device, but as a "Child- resistant" closure, a spray-dome, a spray guide, or highly decorative cover. Table IX may be used to illustrate a program for the incoming inspection of 150,000 to 500,000 protective covers. Other special inspections include the checking of "Child-resistant" closure operation, orifice and insert system of spray domes, and so forth. Incoming Inspection of Corrugated Shipping Containers Corrugated shippers are formed by gluing a Kraft paperboard corrugating medium between two Kraft paperboard facings. They are generally used for six- packs, twelve-packs, and twenty-four-packs of finished aerosol containers, in which case they are ordered in 175 and 200 psi. Mullen test bursting strengths. The facings are then 42#/M sq ft with 26#/M sq ft medium; e.g. 42-26-42, for the 200 psi boxes and usually a combination such as 42-33-33, 42-30-33 or 42-26-33 for the 175 psi cases. They are preferably received as 50-pack
Quality Assurance 457 Table IX Incoming Inspection Program — Caps Class AQL Sample Ac. Re. 800 10 11 Critical 0.65% Description: Cap not proper color or surface texture. Cap is sufficiently loose on can that it will not support weight of filled unit. In the case of full diameter caps, cap should support weight of filled unit held at 45° angle. Printing is illegible. Flash is sufficiently excessive as to interfere with operation of unit or cause production problems. 800 21 22 Major 1.50% Description: Cap is overly tight. (Check corresponding can or valve cup diameter before condemning cap.) Portions of plastic are missing, due to cold molding. Cap is dented, distorted, cut, squashed, cracked or badly blemished. Cap is outside of purchasing specifications. Where caps contain sliding segments slides fail to move freely, resulting in sustained sprays or other defects. Antistatic property is missing, when specified. Printing is significantly misregistered or partly missing. Embossments or debossments, special surface textures or other features are substandard or missing. 800 21 22 Minor 4.00% Description: Caps have dust, lint, dirt, grime, soil or oil. 10 0 0 Special — Description: Caps do not match up with specified valve set to proper stem height. Applies to spray domes where actuator is integrated with cover. Special — Description: 10 Caps become extremely loose after being applied and removed several times, indicating severe depredation of hold-down lugs. bundles, combined onto pallets and strapped down with a minimum of five bands. Folded corrugate or scrap cases should be placed at corners under the bands to prevent serious denting or tearing of the top cases. The average filler is not equipped to study and verify Mullen test strength or Compression Strength, even though he is the one responsible for conforming to the Freight Classification Rule 41, which relates Mullen test results to the weight of the packed case; e.g. a 175# case may weigh 20 to 40 pounds when packed. Instead, the filler or aerosol manufacturer generally selects other routes to ascertain proper case strengdi. Table X may be applied to the incoming inspection of 3200 to 10,000 corrugate cases. Table X Incoming Inspection Program - -Cases Class AQl Sample Ac. Re. 20 0 1 Critical 0.65% Description: Size is incorrect, by inside dimensions. a. Width and Depth must be equal to the sum of can diameters and divider thicknesses plus from yi6" to 3/i6". b. Height must equal can height, plus 0" to y8". Boxmaker's specification seal is missing. Printing is grossly misoriented or of incorrect color or shade. 0 1 Major 2.50% 5 Description: Case is so dry or brittle that fold score lines crack upon set up. Glued or taped seal is in poor condition. Box is water-stained, excessively dirty, grimy or oil stained. Box is seriously parallelogrammed upon set up.
458 The Aerosol Handbook Distance between top flaps exceeds !4 " and distance between bottom flaps exceeds %"• (Ideally, flaps should touch about V2 " above made up case. Box has incorrect flute. Minor 6.50% 0 1 Description: Box is severly cut by straps or bands. DOT Precautionary symbol is omitted, where specified. Special tests are sometimes applied in order to cope with special requirements. One major marketer applies a compression test where the top to bottom strength must be 15# per perimeter inch. Those who fill aerosols for this firm are well advised to obtain suitable testing equipment and put it to work. INCOMING INSPECTION REPORT PRODUCTION DESCRIPTION AND SIZE PART NAME PART NO._ PURCHASE ORDER NO. ^___ LOT SIZE SAMPLE SIZE _SUPPLIER'S LOT NO.. DATE RECEIVED REFERENCE: MIL-STD-I05D TABLE II DESCRIPTION OR SPECIPICATICK UKDER TEST Major Functional Defect; AQL- % Minor Functional Defect; AQL= % Major Appearance Defect; AQL= % Minor Appearance Defect; AQL= % INSPECTION DISPOSITION SALVAGE DISPOSITION INSPECTED BY_ APPROVED BY _DATE_ DATE Figure 17. Incoming Inspection Report Incoming Inspection — Final Comments In an aerosol system, where all interlocking components must function jointly, it is common to find that a critical defect is caused by the concerted action of two or three minor defects. Where such instances may arise, past experience may dictate elevation of particular minor defects to the major defect category, or particular major defects to the critical category. Since it is common to use the acceptance number or rejection number to apply to the total of all defects within a given classification, adding description categories to the classification has the effect of making the inspection level somewhat tighter. Many incoming inspection programs are set to contain more or fewer descriptive categories than are presented in the examples given. In many plans one or two reserve categories are provided, to cover the unanticipated type of defect. In others, these are described in a "Remarks" section. In some incoming inspection programs, different language or categories may be used than the critical, major and minor defect groupings used here. An alternate plan is as follows: Major Functional Defect Minor Functional Defect Major Appearance Defect Minor Appearance Defect AQL =0.10% AQL =2.50% AQL =0.25% AQL =6.50% Forms are usually provided for making a permanent record of each inspection, and in many cases customers may ask their filler to routinely submit copies of these for review. The forms contain sections for component description, data presentation, and component disposition. The data presentation section carries a blank column for defect description, usually not longer than a dozen defect possibilities. For each defect type there is a wide space for each classification that might apply. These spaces accommodate "laundry lists" of the "111" variety that may be accrued for each defect as inspection progresses. These lists are never longer than 22, since the attainment of this number signifies rejection, regardless of classification, if MIL-STD-105D Table II is being followed. If rejection is signified under the component disposition section, it is desirable to indicate what means of salvage, if any, may be applied. Sometimes this is not possible, if a delayed final determination is necessary. Causes for the variance from specification are determined, to see if they are justifiable or anticipated.
Quality Assurance 459 Meanwhile, the quality control department sees that a "HOLD" tag is placed on each pallet-load of defective merchandise. If the cause for rejection is marginal, a management decision may be made to override the rejection, in which case an "ACCEPTED" tag is placed over the "HOLD" tags. Such goods are considered to have been approved on an extraordinary basis, due to the nature of the defect, the need for the component in production and so forth. In other instances it may be determined that 100% inspection can be justified to cull out faulty stock. In this case the "HOLD" tag is covered by a "REWORK" tag. When the rework is done and reinspection shows that the stock has attained the proper quality, these earlier tags are covered by an "ACCEPTED" sticker. Finally, where there is no recourse but to destroy the goods or return them to the supplier for credit, a "REJECTED" tag is applied. All these tags are ideally about 1 Yi " by 5" long, come in appropriate colors, are annotated for a brief descriptionof lot and defect, and are produced with gummed backs. Some plants are so arranged that any pallet not bearing an "ACCEPTED" tag will be refused by production. Whenever components are reworked or rejected, an inventory adjustment must be made. To be meaningful, the inventory should consider only accepted goods. A "Reject Inventory Adjustment" form is provided so that correct amounts of rejected components can be removed from good-stock inventories and listed under a separate classification. Care should be taken when transferring from a previously accepted quality control level to a more stringent one without giving due notice to the suppliers. Similarly, a recent Federal Court decision has protected the interest of suppliers by stating, "Acceptance of out- of-specification materials over a prolonged period of time nullifies the right to reject materials within the range previously accepted." Accepted components do not always maintain the level of quality displayed at the time of inspection. If the goods are exposed to: a. Storage for long periods of time, b. Bleaching effects of sunlight, c. Staining effects of rain water—broken windows, leaking roofs, d. Softening effects of humidity and temperature, e. Scrapes, bruises, or scars, caused by inplant translocations, f. Accidents — break in an ammonia line or water pipe — oil spray, g. Depredations of rodents, insects, birds or bacteria, then the quality level will decrease. Such effects can often be minimized by First-In/First-Out (FIFO) warehouse rotations, but it is still a good plan for the quality control group to cursorily reinspect components as they are brought to the manufacturing area. At the same time they can verify age and part number. It is common for certain components to be manufactured under an AQL of 0.10%, for example, and then be found to exhibit an AQL of 0.25% when examined at the customer's plant. The differences involve bruising, dust, abrasions, weather effects and so forth. Incoming Inspection of Chemicals Incoming chemicals should be subjected to a reasonable degree of incoming inspection, at the YOUR COMPANY NAME YOUR ADDRESS • CITY. STATE. ZIP CODE • TELEPHONE NUMBER I REJECT INVENTORY ADJUSTMENT ) Dote Product Customer . „_——— Port Nome & Number Port Description Reason for Rejection No. of Cartons No. of Units. Shift Inspector QC4 Figure 18. Reject Inventory Adjustment
460 The Aerosol Handbook minimum level of one sample per lot, and generally at the level of the square root plus one of the containers in each lot. All containers should be tagged with yellow "HOLD" stickers until released, when a green "PASSED" or similar sticker is placed over the yellow one. This is a mandatory part of any CGMP progam. Depending upon the testing requirement, liquid samples will be withdrawn at the rate of 12-ounces to 32-ounces. Solids will be sampled at the rate of about 8-ounces to 16-ounces. Data relating to lot number, name of commodity, weight involved, date received and so forth should be attached to each sample. Chemicals arrive in various types of containers: tankcars, tanktrucks, compartmented tankwagons, flexible bulk-packs (pillow-packs), drums, bags, fibre drums, carboys, plastic kegs, tins, pails, bottles, wooden cases and so forth. Each packaging mode has its own unique set of subdivisions. For instance, drums may be made of stainless steel, aluminum, extra-heavy gauge steel, plain steel, lined steel, galvanized steel, tinplated steel and other compositions. In some instances either thin, two-piece polyethylene liners or thick, one-piece polyethylene inner drums are used in conjunction with steel outer drums. Unit sizes may vary from 150,000 pounds, all the way down to 1-pound. A lot may consist of one bulk shipment, or from one to about 60 smaller containers. It normally represents the manufacturer's batch, but it may also relate to a composite of two or more batches collected in a storage tank and analyzed as a unit. All chemical YOUR COMPANY NAME YOUR ADDRESS CITY. STATE. ZIP CODE PRODUCT AMOUNT MADE BY DATE CHECKED BY TESTS MADE . REMARKS Figure 19. Typical Label for Batch Samples sampling should be done on the basis of lot number. The sampled drum or other container should be identified by a sticker tying it to the sample bottle identification. (This is required in a CGMP program.) During sampling, the condition of the container should be noted. Abnormalities must be recorded. Repairs should be instituted where possible, such as taping up torn bags and turning punctured drums in such a position that leakage will cease. Any containers without seals, showing rust or foreign materials, found to be punctured, leaking, soaked or lightweight should be "HOLD" tagged and set aside for special disposition. Inventory adjustments and claims may be necessary where substantial leakage has occurred. Certain chemicals are harmed by exposure to air. Sodium hydroxide will liquefy, hydrous zirconium oxide will dry out irreversibly, sodium nitrite will oxidize slowly, and volatile solvents will evaporate. These factors reduce the chance for eventual acceptance of punctured containers. All drums and smaller containers should be adequately labeled or stencilled with content identity, lot number, date, customer's part number, and net weight. Further information is sometimes given, such as gross weight, drum number and purity range. Containers are suspect, where this key information is incomplete or missing. Other problems arise when color-coding is incorrect, or where units are of improper size. The use of wrong construction materials can cause problems. Contract fillers may sometimes have to inventory containers of the same chemical consigned to more than one customer on a specific basis. In this case, special tags must be applied to indicate the customer for whose product the container must be used. Warehouse segregation is suggested for such materials. In fact, certain marketers feel much more confortable if their raw materials are segregated together. When the time permits, propellent tankcars should be checked for valve and flange leakage by applying a detergent solution across the joint, using a common oil can. Any leakage of gas will be translated into foam bubbles for easy detection. Tankcars of petroleum distillates often contain tramp water on the bottom, so it is a good policy to drain some of the liquid through the bottom valve and check for presence of water and rust, prior to bottom sampling. In some cases ten or twenty gallons will have to be poured onto the ground to minimize the amount of water pumped into storage
Quality Assurance 461 tanks. This may necessitate an inventory adjustment and claim. During die sampling of drums it is good practice to peer through die liquid, using a flashlight, to check for off-color, lack of clarity, possible sediment, torn plastic linings and odier problems. Sodium lauryl sulfate solutions and similar detergent liquids will rapidly attack steel and become discolored if die plastic drum lining is breached. Once die sample is brought into die Analytical Services Laboratory or comparable area, it is divided into eidier two or three smaller sample botdes as follows: a. Working Sample of 4 to 16 ounces. This is for immediate analysis. b. Reserve or Reference Sample of 4 to 8 ounces. This is placed in storage for at least one year. c. (Optional) Standard or Pre-shipment Sample to Customer, of 4 to 8 ounces. These fresh botdes are prompdy labeled widi chemical identity, lot number, date of sampling, part number and so forth. Specially prepared labels are often used for diis purpose. If diey are of die "Stik-Tite" variety it is sometimes necessary to add transparent tape to prevent eventual peeling. Where die chemical is expensive, such as perfume, alledirin, SBP-1382 and so forth, it is customary to use smaller botdes for sample purposes. Many marketers require submission of samples for each raw material and batch. In some cases diey will authorize shipment of die chemical or finished aerosols only after diey complete dieir own analyses of submitted samples. In others, die filler must await customer approval of raw materials before making his batch; odierwise he makes die batch and fills on his own recognizance. These procedures are bodi expensive and time-consuming, involving airmail transport of samples, telephones approvals, and still a delay of a week or two during which die filler must inventory large quantities of raw materials and components before filling. In some instances diis approach can be justified by die fact diat many fillers do not possess die expensive devices for instrumental analysis which are needed in order to correctly identify certain chemicals. Raw materials may be analyzed by means of a huge array of mediods. There are diree levels of analysis, in terms of time required: visual, physical and chemical. Far more materials are rejected on die basis of visual analysis; e.g. color, clarity, texture, odor, rough viscosity and foreign matter, dian by die physical and chemical procedures combined. The raw material supplier is often requested to submit a "Certificate of Analysis" widi die shipment. In many cases the certificate will contain information that would be very difficult for the filler to confirm precisely. In such instances a relatively cursory examination will usually suffice. The results of incoming chemical inspections are recorded in bound notebooks, widi die notations dated, signed and counter-signed, and sometimes also on "Raw Material Analysis Form" sheets which may be forwarded on to die marketer. When incoming inspection is passed, a "Raw Material Release" sticker or "PASSED" sticker is affixed to all drums or odier units of die approved lot. The Compounding Department is dien free to use this stock in batchmaking operations. In instances where a material has a limited storage life, such as shellac solutions, sodium hypochlorite solutions and polymer emulsions, a note calling for re-examination before use may be attached to die container. RAW MATERIAL ANALYSIS REPORT MATERIAL ANALYSED DATE GENERAL INFORMATION SUPPLIER DATE RECEIVED SUPPLIER'S LOT NO. OUR LOT NO. QUANTITY CONTAINER CONDITION ROUTINE ANALYSES TEST Color, Odor fe Clarity Specific Gravity @ °C. REFRACTIVE INDEX @ Z5°C. Viscosity, Brookfield @ UC. Spindle No. RPM = pH VALUE @ °C. Solids Content - Pan Dry (Atm. ) Solids Content - Pan Dry ( "Vac ACID NUMBER Acid Titration to pH " Base Titration to pH * IODINE NUMBER Moisture Content (KFM) Hexachlorophene Content RESULTS 1 SPECIFICATION INTER PRET'N SPECIAL ANALYSES Spectrophotometry Trangmittance Spectrophotometry Absorbtion Spectrophotometry Extinction Coefficienj G/L Chromatographic Analysis (Tape chart to back side) Melting Point Analysis Mixed Melting Point Analysis FINAL RESULT ANALYST Figure 20. Raw Material Analysis Form Next Page
462 Previous Page Quality Assurance During Compounding The quality control department is ultimately responsible for certain aspects of the compounding operations. They must assure that a clean set of tanks, hoses, filters, pumps and so forth are available. Debris on top of drums, tank covers and scale heads indicates substandard housekeeping. Tools, food and other personal items should be stored in approved locations. Weigh- scales should be checked regularly for precision. Any non-functioning equipment should be clearly identified as such. Where customers require segregation of their raw materials, such practices must be set up and man- tained. All chemicals brought to the compounding area must be within a proper temperature range. In many instances drums of alcohol, glycols and other solvents must be warmed in order to dissolve solid ingredients at DATE: lg-PtC-lTO SUPERSEDES: 31-OCT-1969 COMPOUNDING INSTRUCTIONS PRODUCT: COMPLETE QERHICIOE SPRAT CUSTOMER: HPKSEKEB LABORATORHS. IMC. PART NO. 117269 117679 117706 11708J 117983 117001 122002 11769li INGREDIENTS Dowlcide Mo. 1 Dowlcide Mo. * Surfactant 0-13 Inhibltrex 0-17 Perfuse #*6-578 De-loniied water (Spec. <i) S.D.Alcobol 40-2 (Anhyd.) Propellent-12 CONCENTRATE TOTAL FORMULA 0.1768* 0.0370* 0.1392* 0.1250* 0.1500* 9.50*5* 89-6675* 0.1*1** 0.0296* 0.111** 0.1000* 0.1200* 7-6036* 71.89*0* 20.0000* NET WEIGHT SPECIFICATION: *08.* « 7-0 grass. METHOD OF FILLING: n.T-C or Tww.f... B.fri,.r.Hn.■ If 0-T-C, use 21" Hg° Tacuua criap. BATCHING INSTRUCTIONS INGREDIENTS Dowicide No. 1 Dowicide No. * Surfactant G-13 Inhibitrex Cj-17 Perfuac #*6-578 Deionized Water (Spec. *) SD.Alcohol <io-2 (Anhyd.) Propellent-12 ( REPORT 0NL1 1000 lba. l.*l* 0.296 1.11* 1.000 1.200 76.036 718.9*0 K200.000) 10.000 lba. l*.l* 2.96 11.1* 10.00 12.00 76O.36 7l89.*0 (2000.00) 50.000 lba. 70.70 1*.80 55.70 50.00 60.00 J801.80 359*7.00 (10000.00) PROCEDURE: Add saall ingredients to alcohol asd than add deionized water. Use etainleae ateel equipaent only. Filter at five Microns. 1000 Cane will require 903 lbs. of total foraula - theory (no losses). 1000 lbs. of total foraula will produce 1107 units -theory (no losses). SUBMITTED: CHECKED: Figure 21. Compounding Instruction Sheet The Aerosol Handbook a reasonable rate. Relatively low melting lanolin derivatives, waxes, amides and other chemicals are preferably pre-warmed in a "hot room" until they become liquefied. It is a good policy to warm for at least 48 hours, and then "stick" the drum to ensure complete liquidity. The drum is then rolled around for a few yards in order to make sure the contents are homogeneous, especially if only part of the contents are to be used. It is desirable to have an approved procedure in making every batch. This becomes critically important for aqueous w/o or o/w emulsions; non-aqueous emulsions and solid dispersions; since phase and particle size may be affected adversely by the use of incorrect compounding methods. Research personnel should be on hand for the first preparation of any new batch. If there are delicate or critical aspects, research control should extend across the first several batches. A "Batch Record" or "Chemical Report" should be filled out for every batch made. Whenever possible, batch sizes should be standard, rather than calculated to meet the inventory of packages to be filled. Details for formulas and batchmaking should be written out on a permanent "Compounding Instruction" sheet. It is common for such sheets to list the complete formula, weights of ingredients for one or two batch sizes, theoretical units filled for each batch size, and a procedure for compounding. When a batch is to be prepared, a blank "Batch Record" sheet is filled out with various details, including the theoretical weight figures for the proposed operation. Whenever these figures are not direcdy available from the "Compounding Instruction" sheet, they are worked out factorially and checked by either the quality control or research department for accuracy. As the batch is produced, each ingredient is recorded on the sheet at the time of addition. Flushing material usages are also recorded. Ideally, the records should indicate the tank number used for compounding and holding the batch. The tanks themselves should also be annotated, in order to avoid the chance of using the incorrect batch in a filling operation. The completed "Batch Record" sheet is submitted for inventory control, and copies are made available to the customer if desired. Samples are withdrawn at the end of each batch, after making certain the batch is well mixed and homogeneous. In some instances interim samples may be taken. For instance, it is a good plan to check the pH
Quality Assurance 463 of hair spray concentrates after only the resin and AMPD are added, simply to make sure the proper degree of neutralization has been achieved. Batch samples are analyzed by visual, physical and chemical methods, such as those oudined in Table XI and XII. Some marketers demand proof of presence for each ingredient. This can bring on some difficult analytical procedures because of masking influences impressed upon the system by other ingredients. Batch analysis forms are always filled out and copies made available to customers on request. Alternately, the customer may ask for a "Certificate of Analysis" to cover research type tests on both the batch and completed aerosol package. During their inspection of compounding facilities, the quality assurance people should check for use of proper pumping equipment, proper filters and special devices, such as shear-pumps or homogenizers, adjusted to proper settings. The use of copper, brass or bronze fittings cannot be tolerated where ammoniacal or sodium lauryl sulfate type solutions are involved. Copper will go into solution and cause can corrosion problems of the most serious types. Periodic samples of deionized water should be taken and rechecked for conductivity. With all these safeguards the total compounding operation—often one of the more troublesome and wasteful steps in the manufacturing process—should be brought into proper control. Manufacturing Procedures Every manufacturing sequence is unique, according to production line and product characterization. On a glass line, for instance, it is customary to pressure check all empty ware by applying a momentary pressure of 150 psig. This is not considered necessary on can and tube lines. The ideal production line will have two Turn to page 467 YOUR COMPANY NAME BATCH RECORD SHEET YOUR COMPANY NAMF CERTIFICATE OF ANALYSIS No. ISSUED TO 0«-« Sn-» CHEr/'CA.S USED [ 1 Pd't l\o 1 OC--MI 1 1 | "^ H 1 j - ' «l 5-i 6 j '' 8 I 9 , iC . " 12 13 771 TOTAL WEIGHTS We.qKt ana Batch Nl Flujh.no, Material el s HoWinq tanl nun-.ber New Mm Drum Out Art ni% M.. V.«n Ar-,ln^l Lot BATCH WEIGHTS Theoret.cal Act^i 1 i 1 Mrtkw tank number Production Code The following data were determined for aerosol productions identified as: PRODUCT NAME _^____ ____ BATCH NUMBER(S) FILLING DATE(S) PRODUCTION CODE(S) TEST 1. 2. 3. 4. 5. 6. 7. e. ANALYSIS ANALYSIS ANALYSIS COMMENTS Figure 22. Batch Record Sheet Figure 23. Certificate of Analysis
464 The Aerosol Handbook A listing of many of the standard physical and chemical methods is as follows: Table XI No. Test Method Process and Significance 1. Ash Content. 2. Aniline Point. 3. Boiling Range of Propellent. 4. Color Index. Gardner Scale. Klett Colorimeter. Tag-Robinson. 5. Conductimetric Analysis. 6. Density (gm./ml.) Westphal Balance. Pychnometer. 7. Freezing Point. 8. Flash Point. Tag Open Cup—CSMA. Tag Open Cup. Tag Closed Cup. Martins-Pensky Cup. 9. Fire Point. 10. Gas Gravity Analysis. 11. Kauri-Butanol Value. 12. Gas-liquid Chromatography. Thermal. Flame-Ionization. 13. Low-Volatiles Content. 14. Liquid Density, under pressure. 15. Refractive Index. 16. Solids Content. Heat to constant weight at 1000°C. Measures metal oxides, usually present as impurities. Heat with aniline until clear. The higher the temperature the more aliphatics and less aromatics. Measure temperature at which 5% and 85% has boiled away. Difference should be less than 1°F. if pure compound. Colors are compared to standard colors. A measure of purity, lack of air oxidation and lack of pyrolytic degradation in manufacture. Immerse two electrodes and measure resistance to flow of standard current. Measures activity; e.g. apparent ionic content, as ppm. NaCl, ppm. CaC03, etc. Measure weight of fixed volume or displaced volume. Compare with standard tables to verify presence and purity of liquids. Cool slowly until freezing commences. Compare with standard values to verify presence and purity. Slowly warm sample in standard cup, periodically testing vapor for flammability with free flame. At flash point, cup momentarily fills with flame. Used to depict type and purity of flammable or combustible solvents. Similar to above, but temperature at which flame becomes self-sustaining. Fill evacuated weighted bulb of known capacity with propellent gas. Net weight converts to molecular weight or average molecular weight. Solvency index in kauri gum plus butanol. Measures polymer solubility parameters. Separates and quantifies components of gas mixtures, solutions and "pure" solvents—preferably using integrator. Preferential absorb- tion principle. Controlled boiling against standard and temperature. Measure volume of known weight of propellent, using calibrated pressure buret at known temperature. Measure, using various refractometers. Compare with standard readings for presence and purity. Warm to constant weight at 105°C, sometimes under partial vacuum. Determines low-volatiles content.
Quality Assurance 465 Table XI — Continued No. Test Method Process and Significance 17. Spectrophotometry Infra-red Visible Ultra-violet 18. Melting Point. 19. Mixed Melting Point. 20. Sieve Test. 21. Solubility. 22. Viscosity. Brookfield Ostwald Prepare sample or derivatized sample in cuvette or on plate. Determine transmission or absorbtion at critical wavelengths or over prescribed wavelengths. Peaks give compositional data. Height gives concentration data. Melt capillary tube of solid against thermometer held under glycerin in a Thiele tube. Compare melting point to standards. Sharp melting point indicates good purity. Intimately mix equal parts of sample and the pure material it is thought to be. Sharp proper melting point signifies pure sample of correct composition. Low, slushy melting indicates different material. Determine percent of sample passing through one or more standard sieves. Compare to specification. Determine ability of sample to dissolve in specified solvents, examining solution for solid impurities. Measure, using viscosimeters, at one or more temperatures. Compare to standards. 23. Specific Gravity. Hydrometer Baume Hydrometer Alcohol Proof Hydrometer 24. Polarimetry. 25. Specialized Tests. Slowly immerse float-ball hydrometer into temperature equilibrated liquid. Read at meniscus. May be done in P-12 bath at -20°F. for most propellents and blends. Then called "Densimetric Analysis". Compare to tables. Determine percentage of optically active compounds by twisting of polarized light slit. Compare to tables. As submitted by various customers. Table XII No. Test Method Process and Significance 1. Ammonia Determination. 2. Acid Value. 3. Aldehyde Content. 4. Copper Content. 5. Chloride Content. Heat sample in strong lye solution to distil ammonia as gas. Catch in water and titrate with standard acid. Use direct titration with standard 0.1 N. NaOH to get neutralization equivalent. Acidometric method where hydroxylamine hydrochloride reacts in ethanol/pyridine to give an oxime and HC1. Extract copper with chloroform after chelating with Neocuproine (2,9-Dimethyl-l,10-phenanthroline). Color. Buchler-Cotlove Chloridometer. Orion potentiometry. Methods of Fajan, Mohr, Volhard or Caldwell.
466 The Aerosol Handbook Table XII No. Test Method Process and Significance 6. Ethanol Content. 7. Ethanol Purity. 8. Hexachlorophene. 9. Aldehyde. 10. Aldehydes & Methyl Ketones. 11. Alcohols or Phenols. 12. Aliphatic Amines. 13. Aryl Amines. 14. Carboxylic Acids. 15. Acetic, benzoic, and dicarboxylic acids. 16. Saponification Equivalent for esters. 17. Unsaturation Equivalent for olefins. 18. Iodine Number, for Fats and Oils. 19. Nitrite Ion. 20. Substituted Phenols. 21. Sulfate ion. 22. Phosphate ion. 23. Lead ion. 24. Air in C02 Aerosol Packs. 25. Specialized Tests. Standard method as approved by Alcohol, Firearms and Tobacco Division; Department of the Treasury. Add potassium permanganate solution. Color fade should be zero to very slight during half hour test. USP Method. 1 Gram of sample in 100 ml. of SDA-3A is titrated potentiometrically with 0.1N. NaOH solution. Heat 30 minutes in 0.8N. sodium hydroxide plus hydrogen peroxide. Titrate for amount of carboxylic acid formed against a blank. React with excess 10% sodium sulfite solution at 32°F. and titrate the alkalinity developed with 0.5N. HC1. Add 2.000 ml. of 15% acetic anhydride in pyridine to 50 mg. of sample. Boil, cool, add 25 ml. water and titrate against blank for loss of acetic acid in formation of alkyl or aryl esters. Use direct titration to pH = 5.5 with 0.1N. HC1 to get neutralization equivalent. Use direct titration to pH = 2.8 with 0.1N. HCI to get neutralization equivalent. Use direct titration to pH = 9.0 with 0.05N. NaOH, preferably against blank, to get neutralization equiv. Dissolve 0.3 g. in 20 ml. water. Add 1 g. KI, 5 ml. of 3% KI03 and 25 ml. 0.1N. Na2S203. After 20 minutes back titrate with standard I2 solution to get neutralization equivalent. Reflux ester with excess NaOH in ethanol standard. Titrate remaining excess with 0.25N. HCI. Wijs Method. Add an excess of standard I2 solution in glacial acetic acid to chloroform solution of sample. After 30 minutes in the dark titrate with standard 0.1N. Na2S20:i solution against blank. Analysis 17, where answer is determined as grams of I2 consumed by 100 grams of sample. On a spot plate add a 10% solution of 3,7-thiaxanthenediamine-5,5- dioxide in 48% HBr to a few drops of sample. Blue color indicates nitrite. Determine U.V. absorbence against standards. To 200 ml. of solution, add 35 ml. cone. HCI, boil, dilute to 400 ml. and add 10% BaCl2 to slight excess. Filter and ignite precipitate. Weigh as BaS04. Acidify solution with HN03. Boil, filter, and add excess ammonium molybdate. Stir and hold overnight. Filter, dry and weigh as ammonium phosphomolybdate. Evaporate sample with an excess of cone. H2S04. Add water, filter, wash with ethanol, and ignite at 550°C. Weigh as lead sulfate. Zahm-Nagel. Pierce can and lead gases through 50% KOH solution in eudiometer. C02 dissolves, leaving air to be measured at known temperature and pressure. Multiply by 0.19 to determine ml. oxygen per can. As submitted by various customers.
Quality Assurance 467 checkweighers; one after the concentrate filler and another after the gasser. Unfortunately, this is rarely met with in actual practice. Minimum quality control coverage is one operator per line. Principal duties will be weight checking, trouble shooting and taking various measurements. This is an undesirable situation unless the line is slow or moderate speed. Many higher speed lines are set up with one permanent controller, operating out of a satellite control station next to the filler, plus central back-up service for longer routines, plus the sporadic coverage of a roving inspector and the supervisor. The degree of control may be varied according to product and customer requirements. Key line personnel are expected to render production control services, such as frequent checking of weights, vacuum, crimp dimensions and so forth. However, any changes in these various parameters must be made with the authority of the quality control operator. PRODUCTION DATA PRODUCT LINE: 1. CONTAINERS; glen bottle aluminum con plastic bottle one piece three piece CAN CODE- P. M. NO. label ( litho { Mocking feature { map lock ( concave j 2. VALVE TYPE. pressure (ill ( ) valve cup ( ) d.p tube ( ) 3 ACTUATOR, orifice 4. OVERCAP: 5 PROPELLENT: cold (ill ( ) 6. WEIGHTS TARGET rnnr*nlrnlt> prnpnllsnt 7 PRESSURE TC-. F 9. TEMPERATURE PSIG P. M. NO. body orifice: item orifice: vapor top: P. M. NO. reverse to par: index: w/dip tube P. M. NO. metol stocking feoture pressure fill MIN. 8. VACUUM prrtp»ll»nt leak test bath- colort arrow-. 1 ) TOLERANCE MAX. GMS GMS GMS IN. OF HG F F OTHFP INST&I IfTlON A typical production line sequence is described as follows, showing integration of the quality control program: a. Depalletizer. b. Unscrambler. c. Can Cleaner. Inspect for use of filtered and oil-free air under good flow conditions. d. Can Coder. Inspect every 20 minutes for complete, non- blurred code. Change code as needed to reflect new batch or new shift. e. Can Counter. f. Concentrate Filler.* Check at least once per hour at all heads for proper fill weights, proper shut off and appearance of product. g. Valve Inserter.* Check at least once per hour for proper working ability. Check any add-on control systems, that contribute to quality by not accepting valves with faulty components or missing button or diptube. h. Gasser (KPUndercap).* Check once per hour for proper gassing weights, proper degree of can evacuation and correct crimp depth and diameter settings. i. Checkweigher. * Check hourly for accuracy and proper operation. j. Water Bath.* Check hourly to ensure proper water temperature and cleanliness. Air driers should have proper air supply. k. Wiping Table. * Automatic or manual can wiping should be checked once per hour. Should be used as a minor quality upgrade and not as a vitally necessary operation due to hot tank malfunction. Wipers must be clean. 1. Missing Button Detector Check every twenty minutes using control can with button off. m. Capper. n. Auto-Packer (or manual packing station). o. Master case packer. Figure 24. Production Data *These functions require production control and frequent checking to assure proper operation.
468 The Aerosol Handbook Production Sequence Cont. p. Case Sealer and Coder. Check every thirty minutes, changing code as required. q. Palletizer. Check stack and place pallet identification tags on finished loads. QUALITY CONTBOL CHART. ■ rLANT . _ TMf CWt "EIGHT _ SPCCINCATION Llum <fll ONTTCL Ltutli (AOJIAT wrtn vcancATtoM u m E * r~ B I eject LMTJ MIT ON IttHGE CHART AmIcm Mo* UPPER C iOM T—(l*(*>vM 1 1 I 1 I 1 II I | | Bm+H4 1 1 1 1 1 1 Gk» 1 I 1 1 I 1 1 1 | [ | 1 1 1 1 1 ] T*Hl 1 1 I 1 1 I 1 I 1 1 1 ww«.^ 1 1 1 1 | | »-•■ 1 1 1 1 1 1 '-— •'! 1 1 1 1 1 ■a 1 IWT ON RANGE CHART = = I E 1 i - B £ f 1 d l**M> U*« Dun. _ TEMPERATURE AT THE FILLM UNJTOFHEASUREHEHT i 1 T g s r 1 B i y --£ i i CM H AD 1 | m i - 1- 1 1 ! M 1 i 1—1 i 1 'f ^= J ] 1 1 1 1 1 1 1 1 Prior to any production, a "Production Data" sheet is filled out and issued to the production line supervisor and quality control operator. It is the responsibility of the operator to make sure that the proper materials are brought in for production, that proper weights, temperatures, crimping dimensions and vacuum settings are supplied, and that all the equipment has been properly cleaned and serviced. In some instances the operator may be required to obtain "on-line" samples of propellent and concentrate for final laboratory approval. Duality Control Sheet Bo.101 * 112 riMfl1" H*<»IWg RBfOW CASS I MO mCHin RMOBT 1,- 1 1 1 * "W,ii(t>—) I A 7 t » 10 1| 13 F.IIWGm* R«>cX C>.** VHM C>4> Oik* Figure 25. Filling, Gassing Reports Figure 26. Quality Control Report Once the production commences, certain control forms must be worked up for key operations. Among these are: a. Filling Report. Covers the weight checks for product added to the can by the concentrate filler, super-concentrate filler, powder filler, various gassers, gasser-shaker and so forth. Average, range and total weight per can are calculated. Temperatures, vacuum, crimp dimensions and related data may be reported, according to design of the form. b. Checkweigher Report. Covers number of cans lightweight and overweight cast aside by automatic checkweigher. Such cans may or may not be amenable to salvage techniques, depending on circumstances. c. Hot Tank Report. (Salvage Report) Cans found defective in the hot tanking operation are to be reported on the reject report form and then discarded. Additional data may be collected in three or four further report forms: d. Inspector's Shift Report. Covers line inspections such as can quality, code legibility, vacuum in cans, crimp readings, case coding and so forth. e. Roving Inspector's Shift Report. Covers use of correct components, correct codes,
Quality Assurance 469 proper stem height, case sealer glue dispersement, cleanliness and so forth. f. Quality Assurance Laboratory Report. Covers determinations of pressure (usually 70°F; sometimes at 130°F), delivery rate (70°F), total delivery, and other special tests as necessary. g. Supervisor's Shift Report. Covers overall comments; downtime causes, responsibility and remedial action; also special problems. All of these forms are normally filed in the central quality control office area and kept for at least one year. As required, copies may be submitted to customers, to other departments, or to suppliers as a part of claim procedures. Process Control Procedures As the production operation moves along, samples are taken and inspected. Based on the results of these inspections the production is judged to be operating in a normal fashion or to be out of control. The determination is usually made from a control chart, showing either variable data or attribute data. A variable chart describes the extent to which samples deviate from an arbitrary target. Certain samples may show such a large variation as to be considered reject. On the other hand, an attribute chart simply lists samples judged as good or bad. Most aerosol control charts are provided for variables data. Variables data charts are generally used for weight control of aerosol concentrates and propellents. They are rarely used for other applications, such as for crimp measurement analysis, vacuum control, line pressure (generally on cans emerging from gasser-shaker equipment), and the like. Attribute data charts might be applied to rework programs and checkweigher results, but it is more convenient simply to derive a sum of the rejects versus units inspected. The control chart for variables (Shewhart control chart) has become known as the X -r Chart. It may be used whenever the inspection data is collected in actual CUSTOMER CHECKWEIGHER REPORT PRODUCT Procedure 1. Set checkweigher to reject all cans (100%) at plus or minus grai from the average. 2. Insert Low Limit Standard and High Limit Standard cans through the machine once per hour, ten passes per can. 3. Record results by inserting actual numbers in column provided. 4. Notify supervisor if the reject level is less than eight in ten passes. MLVACt MPWT TIME | RAccept HIGH LIMIT LOW LIMIT HIGH LIMIT LOW LIMIT HIGH LIMIT LOW LIMIT Reject Accept Re]ect Accept Reiect Accept Reiect TIME I lAccept HIGH LIMIT LOW LIMIT HIGH LIMIT LOW LIMIT |) HIGH LIMIT LOW LIMIT Reject Accept Reject Accept Reject Accept Reject COMMENTS OPERATOR HATUWE or OCFKT 4 U Can cU *> Pni|is In 'lll-aa IkKIm il«. 0—mn< In CltocMaa. OanaHaa » a. tflMWi Dtont. Owl*, kwMt Oaa.. m D**Hv<r*J - S*aa> E*aa>i •••»•*•> - Vac. «. laafc* . Pw Saan> Ota""** • En* Solaa** In Hm Tank iMM> En*1 •ulaaa' In MM Tank » DwH *' Caa".na Machtna « t>—.«—■ 0» *>aair«.an L.« & i t i « n » Can -natM-ly Flllari Cant Ratasftaa - Carnal L-•**•>' - Saatalat Can. Daawaraa - Q.C L+- Tad* Val.a ImatanatlT *lacari . Can kaaraaarly ■ill**' X ii n n 3* IS M 37 Val-a Mnoaj A* HW*. - Cf.maaa VaU. Laafct t—m Om> Onfica - Hat Tank V*l.a Laafct A> Stat* V.ln Laak* At Cl.«ha* Seal Val.a Fail, Ta Oaaraw •raaarl. V.lv. Fall. T. Sh„i Off (Ga( Mwm) «ii«H»«.> . than Tint* - Oaawaa* Tufc* Ta* Lana - Da-aaaa" In Vat.. *akar M SI Can Dafac1.«a - L.nSa . Dan** - Scranha* - V Warn . Etna)* Can Oamaaaa Ow.aa Sh.ainan' IEma.T) Tn» fn4 SJaW In Hat Tana Im* Eaa> •ulaaa' In Hat Tana Can tWs.n..* - Lttha . Oan*« - leratd Ca* Oamaaa< Dm.na ».»•»•■» ("illaal - 0— f »WM«»** Cajn.Haat.wt •DM C-. 1...I UCTION fc*S VALVES Caaa » ■ 3 3 . i 3a T...I Na.al T...I Tat.l T...I TOTAl M Cant ••■< COMTArNC** Caaa » SI u SJ s* ss M V St St «0 .1 T.tal Na.a< Lati n n „ Cut TOME K •stomirT MAXIMAL 0M HOLD (-oof 1ALVA6I Figure 27. Checkweigher Report Figure 28. Salvage Report
470 The Aerosol Handbook RETURN TO QUALITY DAILY QUALITY CONTROL INSPECTORS DAILY REPORT STOC DATE CANS&LlTHO OR LABEL C0D;ng OF CANS PRESS TEMP VACUUM CRIMP DIAMETER OfPTM WATER BATH TEMP PRESSURE AFTER BATH VALVES DIP TUBE LENGTH ACTUATORS CAPS COOING OF BOXES GLUING & PRINTING Numb*' of Unit* Cpn Label Cod* Comment t On F «■ un U.H.. IttdH.. 3.0. Hr 1 4th H> 1 ! 0 C ln*p«elo size _ 5th H.. 6th H> 1 ™ <>„..•<* (T,m.l . L.™ F 7th H. n.thed (Tinw) tth H>. Figure 29. Inspector's Doily Report SUPERVISOR'S SHIFT REPORT PROOUCT CANS PER M>N PEOPLE USED Why? Mar* poopl* uwd Man Kh**»M. DOWN TIME VK^rfaipw n,vl,s„ Ebctriul •utton Ttppar IN MINUTES _h ExpUin: C^mrflU*«<h.WtMi*iMWI E*Uk — DO NOT FILL >N IELOW . measurements. Certain parameters must be predetermined, as: a. What characteristics should be studied? b. How often should checks be made? c. How should we select the samples to be checked? How many? The characteristics are generally the concentrate weight, followed by the total weight, so that the weight of propellent can be determined by difference. The checks are generally made at the beginning of the production, and as often thereafter as the operator can complete the activity cycle. This should come out to at least 30 individual weight determinations per hour. The samples should be selected with maximum randomness, except that, for filling machines, it is good to get samples from different heads. In some cases, one sample is withdrawn from each head. Most X-r Charts are based upon a sample size of 5, with the operator then adjusting frequency of checks to obtain desired control. COMPANY SIZE CAN ROVING INSPECTOR'S CHECK SHEET (In-process Inspections.) PRODUCT LINE INSPECTOR SUPERVISOR _ DATE _ SHIFT Starting Time (or Listings Correct Can and Condition Correct Valve and Actuator Can Code Condition Concentrate Weights Crimp Diameter (") Crimp Depth (») Vacuum in Can ("Hg°>* Propellent Weights Checkweigher or Balance Scale Water Bath Temp.(°F.) Can Pressure After Bath Blow-off of Water Within Valve Cup Spray Test Result Purge or Sparge Status' Actuator Orientation* Stem Height* Lithography or Label Condition Overcap Condition and Fit Final Pack Condition' Shipper Code Condition Case Sealer Glue Dis-. persement Over-all Line Cleanliness Dver-all Pack Cleanliness Dented or Scratched Units Spray Rate* Container Evacuation * Torque (inch-pounds) * l" Hour 1 2"d Hour 3rd Hour 4*h Hour 5th Hour 6*h Hour 7«~ Hour 8th Hour * When applicable. Place any comments on reverse side. Figure 30. Supervisor's Shift Report Figure 31. Roving Inspector's Check Sheet
Quality Assurance 471 STATISTICAL TREATMEHT OF AEROSOL PRESSURE DATA Table XIII X -r Data Tabulation Specification =69.5gm. PRODUCT XYZ Air Deodorant SIZE 9-ounce 202x706 CODE B171PX & B171PY DATE PRODUCED August 19. 1982 Container Pressures at 70°F B171PY B171PX Pressure 45 46 frequency 1 2 5 Pressure 44 45 48 50 52 53 Upper a Liml-t—ry- prequency 6 6 2 48 50 N - 28 X - 47.6 psig Sigma = 2.23 psi R « 44-53 71.4% above specification 0.0% below specification N - 26 X - 46.0 psig Sigma » 1.62 psi R = 44-50 46.2% above specification 0.0% below specification DISPOSITION Accept on exceptional quality basis. COHMENTS Sales has urgent need for stock in St. Louis Area -J*** fi <*&>«_ DATE ^ T JO,/?,** Figure 32. Statistical Treatment of Data < -2 X-r Chart AZ^ZL / '' 6 J— °r- i / i \ irj I s 1 '! •-_,_ h i 'r 1 i r—' H] sample Number Figure 33. X-r Chart for Weight Control The control chart utilizes several sumbols: X =an individual mesurement or observation. Xi =the first of a series of individual measurements or observations. X2 = the second of a series. X =(bar-X or X-bar); the average of Xi, X2, etc. r =the range, or variation of Xi, X2, etc. The typical work-up of raw weight data into an X -r data sheet can be shown as follows: Can Check No. 1 Gross Tare Net Check No. 2 Gross Tare Net 1. 2. 3. 4. 5. Aver. Range 144.0 146.5 145.1 144.1 144.0 75.6 75.3 75.3 75.7 74.9 68.4 71.2 69.8 68.4 69.1 69.3 2.8 149.2 145.4 146.7 145.7 145.9 76.0 76.5 76.1 75.6 76.8 73.2 68.9 70.6 70.1 69.1 70.3 4.3 Check No. 3 Gross Tare Net Check No. 4 Gross Tare Net 144.4 145.6 143.3 146.2 146.0 Aver. Range 74.8 76.3 75.1 76.4 75.8 Check No Can Gross 1. 145.6 2. 145.3 ♦1 3. 145.4 0 4. 145.9 _! 5. 145.7 Aver. Range Tare 75.8 75.1 75.0 75.9 76.8 69.6 69.3 68.2 69.8 70.2 69.4 2.0 .5 Net 69.8 70.2 70.4 70.0 68.9 69.8 1.3 147.0 147.5 145.8 146.3 145.8 76.5 76.2 75.1 75.0 76.8 Check No Gross 147.8 146.8 145.1 144.6 146.2 Tare 77.3 75.6 76.2 75.3 76.4 70.5 71.3 70.7 71.3 69.0 70.5 2.3 6 Net 70.5 71.2 68.9 69.3 69.8 69.9 2.3 Check No. 7 Gross Tare Net Check No. 8 Gross Tare Net 145.6 146.5 147.2 147.7 145.2 Ave. Range 75.2 76.9 77.1 77.8 77.0 70.4 69.6 70.1 69.9 68.2 69.6 2.2 147.0 147.7 144.8 148.1 145.3 75.8 76.9 74.3 77.1 75.4 71.2 70.8 70.5 71.0 69.9 70.6 1.3 The Grand Average, The Average Range, X = 69.9 grams, r = 2.2 grams This "average and range" data can then be presented in the form of a filling machine control chart, Figure 33.
472 The Aerosol Handbook Many quality control departments do not take the trouble to construct X-r control charts. This may be due to the multiplicity of products and conditions of filling or perhaps because the supervisor is not sufficiently aware of the advantages of statistical analysis. In some cases the control chart is plotted and a copy is maintained near the filler or gasser, so that the operator may have an exact feel for the level of quality he is putting out. Whenever analyses are made later on, generally in the central quality control offices, the line operator must record any changes in settings, so the statistical results can be annotated to reflect whether the machine was operating under a steady state or under a condition of progressive adjustment. Statistical analysis of the X -r chart should not be attempted until at least 20 (and preferably 25) plottings have been made. For best results the operator should use an adding machine. This saves times and reduces the chance for error. The_ first calculation generally involves determination of X , the grand average. If the value of the grand average is significantly above the specification average, then chemicals have been I. PLOTTINGS OUTSIOE CONTROL LIMITS UCL- CENTER LINE •LCL 2. SHIFTS UCL- CENTER LINE -LCL- 3. TRENDS -UCL- CENTER LINE -LCL- Figure 34. Chart of Assignable Causes wasted. For instance, on a one shift production of 100,000 units, if X exceeds the target by three grams, about 660 pounds of material will have been used in excess of theory. A heavy dashed line is oftenplaced on the control chart to indicate the position of X . The Upper Control Limit for Averages, UCLx , and the Lower Control Limit for Averages, LCLx, are then determined by calculation. The average range, F , is first calculated from the individual r values. For the X-r control table in the example, the limits would be: Upper Control Limit for Averages, UCLx =X + A2F =69.9+0.577x2.2 = 69.9 + 1.27 = 71.17 Lower Control Limit for Averages, LCLx = X - A2r = 68.6 grams. The value for A2 is obtained from tables and is dependent upon sample size. For a sample size of four it is 0.729, and for a sample size of six it is 0.483. The Upper Control Limit for Ranges, UCLr, and the Lower Control Limit for Ranges, LCLr, are determined similarly: Upper Control Limit for Ranges, UCLr = D4? =2.115 x 2.2 =4.6 Lower Control Limit for Ranges, LCLr=D3F =0x2.2=0 Again, the values for D4 and D3 are obtained from tables and are dependent upon sample size. For a sample size of four they are 2.282 and 0, and for a sample size of six they are 2.004 and 0, respectively. After the four limits have been calculated, they should be placed on the chart as light broken or dashed lines. Many companies use color codes to distinguish the center lines and control limits, since they serve to make the charts more readily subject to interpretation. One use of the control limits is that variations of an uncommon nature can be rapidly detected. Variation may be caused by changes in the operating adjustment and condition of the machine, the manner in which the operator looks after it, and the uniformity of the concentrate or propellent. So long as all these factors of machine, man and material are constant, the process will exhibit a certain predictable degree of variation and give filling weights close to the average measurement. This pattern will continue until some disturbing influence is brought to bear on the system. When a change
Quality Assurance 473 takes place that causes either a change in the average or a change in the amount of variation, then it follows that an assignable cause is involved. For instance, die first concentrate batch is used up and the compounding department changes over to one which is warmer. It is then good practice to state that die machine is out of control limits, and diat an assignable cause has been superimposed upon the normal constant-cause system of variations. The nature of me disturbing influence should be investigated and the machine readjusted as necessary to restore the original balance. About three times in a thousand incidents a plotting subject only to inherent variation will fall outside die limits. Here a search for assignable cause will be fruitless. Although me protrusion of a plot outside the control limits nearly always signifies presence of an assignable cause disturbance, certain shifts and trends which are still wimin the control limits may also indicate a disturbance. A shift may be indicated when there is a sudden transition in the values of X or r. When this transition is more gradual, a trend is indicated, such as a series of consecutive plottings which move either upward or downward. These changes, if significant enough, form an adequate indication of assignable cause. Any process which is said to be "in control" is not affected by assignable causes. If assignable causes of variation are present, the process is said to be out of control. Not all assignable causes are detrimental, some may be beneficial. It is convenient to think of all matters related to filling accuracy in terms of three functions: specification, production and inspection. First, as described above, the filling machine must be tested to find the probable limits of its capability, and men compared with the specification limits. If the result is satisfactory, as determined by checking the natural variation in filling weight under given conditons of operation, then the filling operation can proceed indefinitely. The final step in weight control is to determine whether the filled quantity is what was intended. This is done by determining me standard deviation, represented by die symbol a' or sigma prime. When a significant collection of weights or other data has been made, the standard deviation from X" can be determined by either the control chart method or the frequency distribution method. Using die control chart memod, we can represent: a'w = -J— =2.2/2.326=0.94 d2 for me earlier example. The value for d2 was obtained from a table and is dependent upon sample size. In this case me sample size was five. For four, the value would be 2.059 and for six the value becomes 2.534. The frequency distribution memod is more complex, but avoids the need to construct a tabulation or control chart and select a synthetic number for the value of d2. It is illustrated by the example presented in Table XIV. If the 0.94 and 0.51 readings for standard deviation are compared, the apparent discrepancy arises from the Table XIV X 69.3 69.4 69.5 69.6 69.7 69.8 69.9 70.0 70.1 70.2 70.3 70.4 75.5 70.6 f 1 1 0 1 0 1 1 0 0 0 1 0 1 1 8 fX 69.3 69.4 0 69.6 0 69.8 69.9 0 0 0 70.3 0 70.5 70.6 559.4 X2 4802 4816 4830 4844 4858 4872 4886 4900 4914 4928 4942 4956 4970 4984 68402 fX2 4802.42 4816.36 0.00 4844.24 0.00 4872.12 4886.06 0.00 0.00 0.00 4942.18 0.00 4970.30 4984.36 39118.04 fX = 559.4 g &9925 n o = yiHl8.04 _(69,927 = V4889-76 - 4889.50 = ^0.26 0.51
474 The Aerosol Handbook fact that the value for r is rounded off, and the size of the study is below minimum in terms of weighchecks. Under the circumstances, agreement between the two methods is acceptable. Since the standard deviation of X is a measure of the amount of variation, it has a direct relationship to the "normal curve", e.g. that found by making a histograph of the frequency distribution. The perfect normal curve is symmetrical about the average, X . It is high in the middle and diminishes as the distance away from the average decreases. All curves derived from histogram studies approach the perfect normal curve, so long as a constant-cause system applies to the process under study. The standard deviation indicates how much variation exists about the central value. The curve actually extends to infinity at both ends, but for practical purposes only up to about 99.73% is considered. One standard deviation from the average will pull in 66.26% of all the individual measurements, according to theory. Two standard deviations from the average will encompass 95.46%, and three standard deviations from the average will take in 99.73% of all measurements. Referring to our illustrative example, the relationship of standard deviation to actual specifications is shown in Figure 36. It can be seen that about 5.5% of the weights are outside specification on a ± 3a basis while about 2.7% still remain outside on a ± 2a basis. In many instances the more laborious histograph approach may be preferred, since the work can be handled by less skilled persons, and the results are actu- Areas Under the Normal Curve, by cr- Figure 35. Frequency Distribution Chart i a + u o o L Total Tolorance=4 .ims. Figure 36. Standard Deviation Chart ally precise, instead of merely statistically precise. The histograph can also encompass phases where assignable-cause variations occur, whereas die statistical approach works best when the process is subject only to normal variations. There are two rather distinct phases of work in establishing a control program. First, the control chart must be used to attain control at a level such that the finished aerosol meets specification. Second, the data must be used to maintain control of the process at this level. If an X -r chart indicates that a filling or gassing process is unable to produce proper weights, then one of four choices must be made: a. Change the process. Revise or replace the machine. Change die concentrate. b. Change die specification. c. Continue filling on an extraordinary basis. d. Continue filling without change and sort 100%. Recognize that the checkweigher will have a high reject rate. In many filling plants weighcheck data is recorded and not subjected to statistical analysis or anything but die crudest types of interpretation. In such instances the control program is almost valueless, and could be readily replaced by the normal production control pro-
Quality Assurance 475 cedures of gross weighing substantial numbers of units at the various filling and gassing machines. The approach gives fairly good results provided the weight of the empty container is automatically tared off using one of average weight for the lot. If the empty container exhibits a standard deviation much greater than that of the fill, as is the case with glass and plastic-coated glass aerosol ware, then this type of weight control becomes more complex. Generally, the stress is placed on the bottles falling below the low limit of the control, and slight overfills are overlooked unless conditions are such that headspace requirements are placed in jeopardy. In a circumstance where the standard deviation of container weight is 2.2 g and the standard deviation of the filler capability is 1.0 g, the estimated standard deviation of the total is formulated as: o' total = yj(a'container)2 + (a' filler)2 = V2.22 + 1.02 = V4.84 + 1.0 = V5l$4~ = 2.41 g. After this, a convenient point in the vicinity of -2a is selected, such as -5.0 grams (-2.08a). On a + 3 tr basis, the weights of 98% of the bottles will then fall between -5.0 and + 7.2 grams from the specification target. Inspection of Finished Aersols The sum of all manufacturing shortcomings is collected in the final product. Bad codes, spiraled labels, short fills, cracked buttons, improper height valve stems and so forth all act to make the final aerosol package less than good in quality. So it is here that a significant portion of the inspection program must be expended. One common practice is to simply remove a random case or two from the production line at regular intervals and proceed to examine each can on a close visual scrutiny basis. Sometimes a surprising number of defects can be noted. Many visiting inspectors examine stock this way. Incoming inspections, when marketers receive stocks from contract loaders, are performed in this manner. Where certain circumstances prevail, special measures may be taken. Sometimes cases may be held until a sampling has been checked 48 hours later by a second pass through the hot tank— as in productions of personal deodorants, diethyl ether starting fluids and other formulas that act to shrink the common Dewey & Almy GK-45 NVH neoprene flowed-in gaskets. Even with very adequate incoming and in-process inspection programs, the finished aerosol package may exhibit some appalling defects. In such cases it will often be found that two or more minor defect conditions have acted in concert to bring about a problem of major proportions. Typical examples are: a. The outside diameter of a common aerosol valve cup is 1.276 ± 0.003 ". Using a closed can bead of the Barclay closed curl configuration, and standard crimping dimensions, this diameter increases by 0.002", to 1.278 ±0.003". Now, the "A" dimension, the inside diameter locus of the QUALITY CONTROL REPORT LINE I PALLETI DATE INSPECTOR . CUSTOMER PRODUCT NAME LOT SIZE __ PRODUCT SIZE SAMPLE SIZE A.O.L. t AC.I RE.I CODE SAMPLE CARTON CHECK COOE LABELS LITHO CLEANLINESS DENTS SCRATCHES WATER IN VALVE CUP SPRAY TEST OTHER: TOTALS 1 3 3 4 5 6 7 8 9 10 11 12 total* AM RELEASED REJECTED HELD Figure 37. End of the Line Report
476 The Aerosol Handbook A listing of some typical finished aerosol analyses is as follows: Table XV No. Test Method Process and Significance 1. Product Odor 2. Product Clarity 3. Product Color 4. Foam Stability (or instability) 5. Pressure, at 70°F. 6. Pressure, at 130°F. 7. Delivery Rate (g s) at 70°F.- 8. Total Delivery (grams) 9. Total Delivery at Angle. (Can Retention) 10. Spray Pattern: a. Diameter at 7". b. Uniformity. c. Particle Size. d. Cast. (Distance) 11. Blow-by During Actuation. 12. Filtration or Sieve Test. 13. Moisture Content 14. Densimetric Analysis 15. pH Value. 16. Undissolved Solids. 17. Flammability Tests. a. Flame Propagation. b. Flashback. c. Closed Drum Test. d. Modified Tag Open Cup. e. Trough & Tower Test. 18. Dissolved or Dispersed Solids. 19. Microbibological Analyses a. Germicidal ability. b. Bacteriostatic activity. 20. Chemical Analyses. 21. Instrumental Analyses. 23. Specific Gravity. 24. Refractive Index. 25. Zahm-Nagel Air Analyses. In beaker or on sniff-blotter, against control. In beaker, against control. In beaker, against control. On plate, against control or stopwatch. Record time for hydroalco- holic emulsions to liquify. Simple prepressurized gauge. A check on proper propellent blend and level; also on vacuum crimp. Assures compliance with ICC (DOT) limitations. Assures proper valve and clear orifices. Assures non-clogging situation. Proper tube length. For starches, paints, etc. Assures dip tube length and proper orientation. Compliance with Model Laws. Proper button and dispersion. Good valve. Proper button and dispersion. Good valve. Proper button and propellent level. Good valve. Proper button and pressure. Good valve. Mildly abuse valve during actuation, checking for faults. Puncture and depressurize can. Pour through filter, checking for retained solder, lint, etc. Karl Fischer Method. Cool to -20°F. in P-12 bath. Open and determine density at -20°F. by CSMA Method. Open can and depressurize. Dilute alcoholic solutions 1 to 1 with deionized water. Check. Shows presence of acid/ base items, proper hair spray resin neutralization, etc. For items containing aluminum chlorohydroxide, talc, silicas, etc. Filter, wash and oven dry. Assures compliance with ICC (DOT) and FHSLA Regs. Pan-dry Solids. For starch levels, etc. For disinfectant sprays or cleaners. For emulsions, subject to microbial degradation. As necessary to prove presence or amount. As necessary to prove presence or amount. Generalized Check. Generalized Check. Determines ml. of air or oxygen in headspace.
Quality Assurance 477 three undercuts or lugs on the inner tube of a typical double-shell cover cap, is 1.267 ( +0.007 7-0.005 "). Using the smallest specification valve cup diameter and die largest "A" dimension specification cover cap diameter, the fit interference amounts to only 0.001". This is hardly sufficient to hold die cover cap securely to the dispenser. The use of a vented can bead would help slightly by making the valve cup diameter about 1.281 ±0.003" after crimping. The use of caps with smaller "A" specifications or four lugs is also helpful. b. If the pull-off resistance of a dip tube is less than about four pounds, pressure loading widi P-12 or propane may cause it to separate from die valve. The problem is intensified if the tube extends clear to the bottom of die can, so that backpressures can be created. The problem is also made more critical if the aerosol formula contains sufficient methylene chloride or similar solvent so that sifnificant swelling and loosening of the dip tube can occur. c. The combination of a minimum crimp diameter (c.a. 1.065") and maximum crimp depth (c.a. 0.192") will generally still give a hermetic seal. But a number of secondary factors may add to diis situation to bring about a certain incidence of crimp leakage. The chance for leakage is increased if shrinkage of die DAREX GK-45NVH flowed-in gasket takes place, due to the effect of the aerosol formula. The use of gaskets on die minimum side of the usual 0.025 ±0.010" specification, on the low side of the usual 283 mg weight average, on the high side of the 0.005" allowable thickness variation per valve, or on the high side of the average Durometer, all contribute toward crimp leakage. d. "Blow-by" is a condition which may occur with female-type valves unless the sealing gasket is swelled more than about 0.002" as a result of contact with the product. The swelling action actually tightens the gasket hole by 0.002" or more, making it fit more snugly about the actuator stem. This potential problem is often brought into reality by the use of Buna gaskets in conjunction widi aqueous formulations. The compositions often act to deplasticize the Buna, rendering it hard and non-resilient. The problem may also be brought on by the use of gaskets with overly large bores, rough-cut bores or out-of-round bores. The use of valves with loose stakes (pedestal crimps) will also have an adverse effect. In many instances diese defects can be detected by examination of die finished aerosol. Some latent problems may surface in a day or two, but diey more often require a more lengdiy time period to mature. In order to cope widi the longer term problem, nearly all quality assurance departments maintain a library of filled aerosol cans. A common procedure is to sample one empty can and valve, plus three filled cans, at the beginning of the run, and then pull one additional can after each hour of production. In this way every complete shift is represented by one 12-pack case containing eleven filled cans and an empty unit as a control. The program is adjusted so that one case will also be collected for runs shorter than one shift. The cans are usually weighed to die nearest ±0.1 gram. The library is maintained from six months to one year, after which it is the usual policy to either destroy the cans or make some non-commercial use of them. In some operations, where the filling codes are related to batch code, it may be more convenient to wididraw library samples on die basis of one or two batch codes per case. Gasket No. Product: Date: Valve Lot No.: Wt. = mg. Ml'*^*^ ^^^f-'Wk Wt' = m9' Th. = 0.0 in. M^A BvSli Th- = 00 in- Wt. = mg. ^SrtjL ^fc&y Wt- = mg- Th. = 0.0 in. ^$£M$^%TfZ$jix£r Th. = 0.0 in. Total Weight Applied Total Weight Removed Variation in Thickness Average Thickness Color Figure 38. Flowed-ln Gasket Anolysis
478 The Aerosol Handbook The central quality assurance laboratory is expected to perform a series of visual, physical and chemical tests upon the completed aerosol unit. The results may be entered in bound notebooks, on forms covering analysis of the finished product, or on other forms which combine the results of batch and finished product analyses. Contract fillers are often required to submit samples of finished aerosols, batches, and sometimes incoming chemicals to their customers. The frequency of sampling, method of transportation and other factors must be considered for such programs. Special labels are usually placed on sample boxes in order to avoid confusion and possible mishandling. Shipping papers are usually prepared on such shipments, since it is customary for the customer to pay a fixed price for these samples, plus transportation costs. Special Projects In addition to their routine duties, the quality assurance department may be called on to perform special operations, usually of a one time nature. Unusual controls must be brought to bear during the production authentication of new valves or other components. Recommendations on the improvement of certain machine functions, such as labeling, may be requested. Added sophistications often originate as special projects, where the department must set up added control procedures. Compliance with the FDA's CGMP regulations often requires extension of the control program, such as defining by record the code numbers of products shipped to specific destinations. As a rule, special projects are highly individual in nature and represent activities within the company directed toward better control, maintenance, recordkeeping, inventories, claim actions and so forth. Current Good Manufacturing Practices One of the largest regulatory activities to impact the quality assurance area for some time has been the FDA's Current Good Manufacturing Practices (CGMP) program. The thrust has thus far been confined to drug products and devices, but there is every expectation that there will be an extension into cosmetics and toiletry products within a few years. In fact, the CTFA (Cosmetics, Toiletries and Fragrances Association) has formally petitioned the FDA to provide just such an extension. The agency has actually drafted GMP for cosmetic products. They have not been introduced as new regulations and implemented because the FDAs Division of Cosmetic Technology has insufficient funds and staff. The FDA is currently sending inspectors out into the field to evaluate the compliance of drug manufacturers with the regulations relating to CGMP. A number of aerosol products are involved, such as antiperspirants, sunscreens, certain types of moisturizing lotions, first aid sprays, athlete's foot preparations and so forth. Persons engaged in the filling and/or packaging of these products must comply with the CGMP regulations or face various forms of censure—even including the padlocking of their facilities in the case of flagrant and knowing violations. The FDA inspectors look about for any evidence of cross-contamination, contamination, dirtyness, lack of sanitation, or loosely controlled plant practices that could have the final effect of allowing sub-standard products to enter channels of trade. Record-keeping is of very high importance, and this includes procedure documentation, training records, double-signed and dated analytical records, batch records and so forth. When the FDA investigator presents himself (or herself) at the plant, the receptionist should contact the Director of Quality Assurance or some similar senior person appointed previously by management to be the primary escort. The escort should be knowledgeable, reasonable, articulate and always polite. There is never any pre-notification of an inspector's visit, so none should be anticipated. The investigator should present credentials, which should include name, photograph, and I.D. number, and these should be examined by the escort. Next, the reason for the visit should be determined. That is, whether a specific problem is involved (possibly an employee complaint, a field complaint involving quality, or a re-check of a previous inspection complaint to see if the facility is now back into compliance), or if a general inspection is planned. The inspector will normally profer Form No. 482, which should contain the purpose of the visit. The investigator may have a camera with plans to use it taking photographs of the plant. While this is not specifically permitted at this time, many companies allow picture-taking as a matter of avoiding possible antagonism and a possibly more severe inspection. The issue will undoubtedly be resolved in the courts one
Quality Assurance 479 day. In the meantime, companies should develop a formal policy on this matter. After the formalities, the inspector will start asking various questions about the plant. The visit will normally take 6 to 8 hours as a minimum and about 3 days as a practical maximum, although some have taken weeks or even months. About 75% of the average inspection will normally take place in the escort's office or a convenient conference room, with people and written records being brought in as needed. To develop evidence that written procedures are being followed, the inspector may ask to see incoming inspection records, batching records, analytical reports, bills of lading and so forth. In addition, about 25% of the visit may be taken up by a slow walk through all areas of the plant and immediate environs. The inspector may wish to question some plant employees and they should be BATCH AND FINISHED PRODUCT ANALYSIS REPORT MATERIAL^ANALYZED _ GENERAL INFORMATION Supplier Botch Number Quantity Under Anolyiis TEST Color, Odor 4 Clor.ty Speof.cGrov.ty ■ 20°C. Retroct.ve lr.de* ' 25"C. Moisture Conteni (K.F.M.) pH Value • 253C. Infrared Spe e t roph orome 1 er AIW,mly ' RESULT 1 SPECIFICATION i INTERPRETATION J j 1 ! ! i ! 1 _A£ld,lt _Ac._d Volue __So.ubrl.ry .Solids Mellmg Point Case Wo 55 no "265 550 780 1100" 1365" Pressor j Del Rote _ 1 CAN ANALYSIS Solids C<>sf \o. | 1650 ! 1915 | 2200 ' 2750 ; 3300 j 3850 Pressure Oe-.Rote S.l,d. r- GAS CHROMATOGRAPHIC RESULTS AREA | t con IDENTITY ' ' 1 i i ! [TOTAL RESULT Figure 39. Batch and Finished Product Report allowed to answer, although volunteered information should be discouraged by the escort. Samples of products may be requested and signed for, using Form 484. During the entire interview, the escort should take notes on any comments made by the inspector. The inspector must be allowed to peruse all documents, training manuals, instructions, shipping papers and other records having to do with adherence to CGMP requirements. Two types of records the inspector is not required to see are pricing information and sales figures. At the end of the inspection, the company will be given a copy of Form 483 which lists observations of alleged CGMP deficiencies. This should be presented and reviewed at a final meeting attended by as many senior company officials as possible. A formal reply from the company should be sent to the District Office of the FDA indicating corrective actions. Any serious violations are listed in a "regulatory letter" sent to the company with a prompt response required. Criminal actions are possible for very serious violations. The forms on pages 480-484 have been used by a major contract filler in performing his own internal CGMP audits, to make sure the various plant locations were in full compliance. This practice can be highly recommended. A full set of specific inspection listings has not been included in the interest of space, but the requirements can be determined easily from a review of the regulatory information in the Federal Register or Code of Federal Regulations. Summary We have presented a fairly technical, definitive picture of the quality control program which should be undertaken by contract fillers and marketers of aerosol products. Every company will have its own idea of the degree to which control programs should be undertaken, although for custom fillers the extent is often dictated by their major customers. The AQL levels, nature of tests, interpretation of results and other factors are often highly individualized, so it must be recognized that we have presented procedures and other data simply as a general guide to those who may wish to form, expand or modify their own quality control programs. The literature on aerosol quality control is rather scarce, with most articles being rather short and of limited scope. It is therefore hoped that this more definitive discussion may serve as a general and in- depth guide over the entire area.
480 The Aerosol Handbook PETERSON/PURITAN, Inc. P/P OVERALL FACILITY CONTROL GENERAL PROCEDURE FOR QUARTERLY OR ANNUAI INTERNAL CGMP AUDIT [METHOD NO. 1 I PAGE 1 OF 3 A. Ask for organization chart indicating education and experience of the management group and showing the responsibilities of the quality group. B. Ask to see written procedures for the following: 1. Employee training on the job and in CGMP areas. 2. Management training on the job and in CGMP areas. 3. Records that show the above are being done on a regular basis. 4. Control of packing materials, from receipt through usage using lot identification in packed batches. 5. Control of raw materials from receipt through usage using lot identification in packed batches. 6. Control of finished product from production through shipment including an adequate recall procedure. 7. Product protection insect, bird and rodent control, and other protection from product contamination. (Hairnets, clean clothes, etc.) 8. Washout and sterilization of equipment. C. Choose one or two packed and released batches at random and ask to see all the related paperwork (or batch packets). Verify that: 1. The batch was formulated properly from an authorized Formula Card or Master Batch Sheet. 2. All required information is available and legible and properly authorized. (If full names are not used, an official initial, signature list should be available. ) 3. All quality limits were met and yield calculations were made. 4. Anything out of the ordinary should be fully explained in writing. 5. Raw materials and packing material lots used in the batch must be identified and analytical records must be readily available and indicate they were in limits and authorized for use. These records must be signed and verified, 6. The batch packet must clearly indicate that the batch was released for shipment. PETERSON/PURITAN, Inc. P/P OVERALL FACILITY CONTROL GENERAL PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL CGMP AUDIT METHOD ND. 1 I PAGE 2 OF 3 D. Observe the making and packing of a batch for proper operating procedures and physical conditions. 1. Are written procedures followed? 2. Are proper dispensing and weighing procedures being followed — accuracy, double weighing, sanitation, etc. ? E. Inspect the entire CGMP area — warehouseing, shipping, packing, processing and laboratory — etc. — looking for evidence of CGMP awareness and compliance. Include the following observations: 1. Is the product sream covered? (Including any empty product containers and rework.) 2. Are containers used only as intended? 3. Is the chance of glass breakage minimized near the product stream? (Locate and/or cover lights and gauges so that accidental breakage will not allow glass to enter the product stream.) 4. Are all containers properly marked for the intended use? (Scrap, rework, etc.) 5. Does a high level of general cleanliness minimize the possibility of product contamination? (Check for dirt, insects, birds and rodents.) 6. Is personnel cleanliness high when contacting the product stream? (Clean gloves for container handlers, etc.) 7. Are adequate heir (and beard) coverings used and worn properly? 8. Are obviously ill employees or those with open cuts or sores able to contaminate the product stream? 9. Does the mop water contain adequate disinfectant to prevent bacterial growth? (Two samples should be plated weekly.) 10. Are food items stored and consumed only in designated areas? 11. Are receipts and inventory clean and free of infestation? Are bags and other material containers properly sealed and covered? 12. Are trucks and rail cars clean and free of pests, foreign matter, odors and other possible contaminants? PETERSON/PURITAN, Inc. OVERALL FACILITY CONTROL P/P HGENERAL PROCEDURE FOF QUARTERLY OR ANNUAL INTERNAL CGMP AUDIT METHOD NO. 1 PAGE 3 OF 3 13. Is the building tight to prevent pests from entering? Are doors closed and screens in place ? 14. Are units and partials of raw materials, packing materials and finished product properly identified (hold, quarantine, released, etc^ at all stages of flow? 15. Do bait boxes and traps show any evidence of rodent activity? (Inspect weekly and record inspection date,) 16. Are specific types of materials confined to prescribed storage areas? (Raw materials, finished product, misc. items.) 17. Are released and held materials stored in the same warehouse raw? 18. Are scales used for raw material and finished product weights properly tagged? Applies to both laboratory and packing lines. Tags should show date of inspection, due date and inspector's initials. 19. Does each bag or container of raw material have a release sticker, and have they been properly voided after use? 20. Are errors and corrections on permanent records correctly changed and initialed? 21. Are raw material dispensing spouts, valves and actuators covered to prevent contamination ? 22. Are hoses and adapters properly covered and stored to prevent contamination? 23. Is tobacco usage confined to approved areas ? 24. Foreign material in any product container is to be considered unacceptable when four particles are visible at 30" or ten are visible at 15". Insects, hairs and other gross foreign material will always be unacceptable. PETERSON/PURITAN, Inc. P/P 1. Is Raw Material identification receipt against purchase orde RAW MATERIAL CONTROL SPECfFIC PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL CGMP AUDIT DATE 198 2 | METHOD NO. 2 | PAGE 1 OF 3 YES checked upon r voucher? 2. Are Raw Material code numbers on the material? 3. Are incoming Raw Materials physically quarantined pending release? 4. Are Raw Materials separated by supplier lot number and code number? 5. Is there a written procedure for acceptance of Raw Materials? 6. Are containers of Raw Material visually examined for proper markings, contamination and damage, and by whom? 7. Are procedures available to the Receiving Department and to Quality Assurance personnel on the disposition of questionable Raw Material? 8. Is there a separate area for holding rejected, obsolete or deteriorated material? 9. Are records maintained of the disposition of all obsolete, rejected or deteriorated Raw Material? 10. Who does the actual sampling and inspection of Raw Materials? 11. Is Raw Material samDling under the supervision of responsible Quality Assurance personnel? 12. Is Raw Material samolins and inSDection done in a clean, well lighted area, and under conditions designed to prevent errors or other prob- NO COMMENTS
Quality Assurance 481 PETERSON/PURITAN, Inc. P/P RAW MATERIAL CONTROL SPECIFIC PROCEDURE FOR QUARTERLY OR ANNUAI INTERNAL CGMP AUDIT 13. Are containers of Raw Material from which samples are taken resealed and identified? 14. Are written instructions available to the inspector for sampling Raw Materials? 15. Are there instructions available to the inspector for handling hazardous chemical Raw Materials? 16. Does the inspector follow the sampling and inspection procedures? 17. Are the samples taken representative of the lot of Raw Material? 18. Is a separate laboratory sample and a separate retained sample taken from the same composite sample of Raw Material? 19. Is there a procedure for Raw Material sample retention ? 20. Is twice the quantity of Raw Materials necessary for all required tests retained? 21. Does the Quality Assurance Supervisor check all Raw Material inspection reports? 22. Are Raw Material storage areas clean, well lighted and adequately ventilated? 23. Do any Raw Materials require storage under special temperature or humidity conditions, and is this done? (Hot room storage, etc.) 24. Do the proper temperature and humidity conditions exist in Raw Material storage areas to maintain acceptable quality? PETERSON/PURITAN, Inc. P/p RAW MATERIAL CONTROL SPECIFIC PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL CGMP CONTROL DATE 1982 [ METHOD NO. 2 [ PAGE 3 OF 3~ YES 25. Are Raw Materials on "HOLD" status cominglec with approved lots of Raw Materials? 26. Are Raw Materials indentified upon release ■> 27, How? Each lot by assay numher? Each drum o"r otber container. Each palletload? 28. Are Raw Material rejections identified? 29. Are Raw Material rejections isolated in special areas ? 30. Are Raw Materials reconciled by receiver number and quantity? 31. Are approved Raw Materials rotated in such a fashion that the oldest stock is used first? (e.g. FIFO). 32. Are chemicals reassayed if not used in one year from receipt? 33. Are those Raw Materials that are received with a certification from the vendor tested for identity as a minimum procedure? 34. Does the Manufacturing Department ever use some material before Quality Assurance accept ance. If so, explain. 35. Are special storage areas available and adequate for controlled substances; e.g. alcohols? Auditor Date NO COMMENTS PETERSON/PURITAN, Inc. P/P COMPOUNDING CONTROL SPECIFIC PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL CGMP AUDIT flpATE 1982 1 METHOD NO. 4 ] PAGE 1 OF 4 1. Is each of the reproduction of the batch records checked for accuracy, dated and signed? 2. Are batch records checked by two responsible individuals and dated. 3. Do batch records provide information £jch as processing materials, components, equipment, packaging, process codes, sterilization methods, date of start of production, date ot sterilization, date of Q.A. release and so forth"> 4. Is each significant step documented immediately upon performance ? 5. Is each process specification requirement in the process checked and double checked and initialed by those present? 6. Are all containers and equipment labeled during 7. Do records for machines and equipment used in the process reveal the sequence of products m anufac ture d ? 8. How are automatic and continuous systems controlled and maintained to consistantly produce material in compliance with designated standards (Such as de-ionized water, or propellent blends.) 9. In the de-ionized water process, how often are records, charts, gauges and such instruments examined by ket processing and/or quality assurance personnel ? Is there a formal approval procedure for any change in the manufacture? 10. Are records and charts filed by product or production date — or not filed. PETERSON/PURITAN, Inc. p/p COMPOUNDING CONTROL SPECIFIC PROCEDURE FCR QUARTERLY OR ANNUAL INTERNAL GMP AUDIT PAGE 2 OF 4 11. Are records and charts filed by batch number? 12. Have all previous batch indentifications been removed from tanks, etc. between batches or at appropriate intervals in a continuous product ion episode ? 13. Who records that the equipment is checked? 14. Are machine and equipment clean-up procedures in writing? 15. Are processing steps adequately separated from each other? 16. Are atmospheric conditions in the processing area adequately temp2rature and humidity controlled ? 17. Are any metering pumps used ruid if so, who checks them for accuracy? (e.g. propellents.) 18. How frequently are chemical and water transfer lines cleaned? 19. Are different products isolated from each other during processing? Rooms? Space only? 20. Is there a dirt collection system available and adequate in the processing areas ? 21. Is the manufacturing program operated in such a manner as to minimize cross-contamination or product intermixing, where more than one product is being prepared or exposed in the sam area? 22. Is the intake of air of drying areas free from odors, fumes, dusts or vapor contaminants ? NO COMMENTS Generally not applicable. Generally not applicable.
482 The Aerosol Handbook PETERSON/PURITAN, Inc. P/P COMPOUNDING CONTROL SPECIFIC PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL CGMP AUDIT 198 2 METHOD ND. 4 PAGE 3 OF 4 26. Are product sampling and testing pians documented? 27. Who performs the testing inspections — Q. A. or manufacturing ? 28. Are in-process checks conducted to assure uniformity of product? (No fish-eyes, etc.) 29. Are all product yields checked by two responsible and trained individuals ? 30. who investigates discrepancies? 31. Are count discrepancies recorded and accounted for ? 32. Who can forward or release a hatch with yield discrepancy — P/PI or customer ? Both ? 33. Is rejected material tagged and quarantined? By room, space only... ? 34. Are reusable containers inspected and cleaned prior to use ? 35. Are all finished batch records verified for completeness and forwarded to customers in a timely and orderly fashion? 36. How are lot numbers assigned and who issues lot numbers? (P/PI, customer, both,.. ?) 37. What is the system for lot number designation? 38. Are adequate precautionary steps taken to prevent cross-contamination or mix-ups? 39. Are workers suitably attired or garbed, including hair coverings ? PETERSON/PURITAN, Inc. P/P COMPOUNDING CONTROL SPECIFIC PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL CGMP AUDIT METHOD NO. 4 PAGE 4 OF 4 40. Prepare a simple "Process Flow Chart" and indicate key process steps and all control points. 41. Is material to be reworked stored separately? 42. Are there reprocessing procedures established implemented and controlled to assure that the reprocessed product or component meets the or iginal or subsequently modified and approved specifications ? 43. Are all products rejected during finished product inspection and later reprocessed subject to another complete final inspection for any characteristic of the product which may be ad- verely affected by such reprocsessing. PETERSON/PURITAN, Inc. f>/R PRODUCTION CONTROL SPECIFIC PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL CGMP AUDIT METHOD NO. 5 PAGE 1 OF 3 1. Is there a person responsible for label control? 2. Is there separate storage of labels to avoid mix- ups? 3. Is anyone responsible for label review? 4. Is the printer count of labels accepted or are labels weighed or otherwise counted on receipt? 5. Is there adequate control of labels issued for use? 6. Are the production facilities inspected prior to labeling? 7. Is there a written control procedure to follow if a significant unexplained discreptancy is found between the quantity of finished goods and the quantity of labels issued to production? 8. Are there segregated facilities for labeling one batch at a time ? 9. Are the following requirements for the labeling area and packaging area met prior to the implementation of these operations: a. Is there an inspection of the labeling and packaging area to assure that the product and labeling materials from prior operations are gone ? b. Is this area inspection carried out by a qualified individual? c. Are product and/or labeling materials found during this inspection removed prior to the onset of a new or different labeling and packaging operation? PETERSON/PURITAN, Inc. P/P 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. Are labels stored and mainta that provides proper identific PRODUCTION CONTROL SPECIFIC PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL CGMP AUDIT DATE 19 82 | METHOD NO. 5 ■ | PAGE 2 OF YE5 med in a manner ation ? Are labeled materials examined for identity? Is there a record of label examinations? Does this record include the date and name of the person performing the examination? Are finished goods properly identified? Is there a finished goods inspection plan? Is it documented? Wbo performs it? Are the results documented? Who has release authority? What is the release procedure? Are internal audits conducted to assure that only released products are shipped to customers? Are the storage areas suitable to maintain product integrity? How are warehouse storage conditions monitored? (Plant warehouse... leased warehouses.) Does the finished product require a code, batch number and expiration date? NO COMMENTS 3
Quality Assurance 483 PETERSON/PURITAN, Inc. P/P PRODUCTION CONTROL SPECIFIC PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL CGMP AUDIT I METHOD NO. 5 PAGE 3 OF 3 25. Is this being properly done? 26. Is shift code issuance control documented to assure non-duplication? COMMENTS PETERSON/PURITAN, Inc. P/P QUALITY ASSURANCE CONTROL SPECIFIC PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL CGMP AUDIT METHOD NO. 7 PAGE 1 OF 3 1. Is the facility edequate in size, lighting, work space and ventilation (or air-conditioning) to perform its function? 2. Is it kept orderly and clean? 3. Is food, drink, smoking, etc. allowed? 4. Are drawers, cabinets, etc. labeled to identify their contents? 5. Are all solvents, standard solutions, chemicals and sample containers identified as to contents? 6. Are expiration dates required on any of these? Are such containers labeled and monitored? 7. Are applicable documents available and accessible, such as test method specifications, U.S.P. references and so forth? 8. Are records and results kept by some logical system to allow ease of filing and retrieval? 9. Are reference standards available, such as I. R. spectra, conversion charts, color standards and so forth? 10. Are laboratory notebooks kept? 11. Does each notebook entry indicate the sample identification, lot number, control number, the applicable specifications and test method, with limits — and are all computations and dates recorded? 12. Is each entry signed by the analyt and dated? COMMENTS PETERSON/PURITAN, Inc. P/P 13. 14. 15. SAJ 16. 17. 18. 19. 20. 21. 22. 23. 24. Does a supervisor or person ersign and date each entry? QUALITY ASSURANCE CONTROL SPECIFIC PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL CGMP AUDIT DATE 1982 [ METHOD NO. 7 | PAGE 2 OF 3 YES in charge count- Is there a statement of compliance with the entry? Are completed notebooks safely stored? SPECIFIC CONTROL PROCEDURES 1PLES Are samples adequately identified to prevent loss or error? Is the sample size (such as 8 Av.oz. or 100 g) specified on the applicable specification? Is there any tracking procedure to make sure samples and test requests are properly handled and dispositioned? How is the sample disposed? Are test requests made via a standard form or verbally? How is work assigned? By technician specialty general distribution, randomly? How are the results communicated to the requester? Verbal, written, standard format, control tickets.... Are there special procedures to handle rejections and/or retests? What data is communicated in a release? Lot number, dates, notebook pages, actual numerical results? NO COMMENTS XXX Receipt of sample constitutes a specific testing request. PETERSON/PURITAN, Inc. P/P CALIBRATION QUALITY ASSURANCE CONTROL SPECIFIC PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL CGMP AUDIT DATE 1982 j METHOD NO. 7 | PAGE 3 OF 3 YES 25. Does the Q. A. Department have a calibration program ? 26. Are the Calibration Standards traceable to the NBS when applicable? 27. Is equipment labeled with the last date of Calibration and the next projected date. (Logbook?) 28. Who performs the calibrations? 29. Is there a routine or preventative maintenance program for laboratory equipment'' PERSONNEL — TRAINING — OUTSIDE TESTING 30. Is the Supervisor or Manager in charge qualified by degree, training and/or experience? 31. Are laboratory technicians formally trained, cross-trained and formally qualified to perform specific analyses? Is there documentation of such training? 32. Are outside test facilities used? 33. How are they selected? 34. How are they monitored? 35. How are their results communicated? Standard format, verbally, letter form (multiple), etc. ? Auditor Date NO COMMENTS XXX XXX
484 The Aerosol Handbook PETERSON/PURITAN, Inc. P/P OWNED WAREHOUSE CONTROL SPECIFIC PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL GMP AUDIT METHOD NO 8 PAGE 1 of 2 1. Are products quarantined prior to release by the Quality Assurance Dept.? 2. Are written procedures established and followed for First-In/First Out? 3. Are written procedures established for a system where distribution data on each lot of product is recorded? 4. Are the drug processing and manufacturing areas of sufficient size to permit: a. Orderling positioning of equipment b. Good and effective cleaning? c. Avoidance of component mix-ups? d. Avoidance of contamination? e. Separate storage of quarantined stocks? 5. Is lighting adequate? 6. Is there a defined single area for rejected materials? 7. is storage of released and un-released material separate? 8. Has a sewer back-up ever occurred? Is there an air-break to prevent this—or other device to prevent back-siphonage? {Traps are unsatisfactory.) 9. Is sewage, trash and other refuse removed from the building and immediate premises in a safe and sanitary way? Regulations in South America The following discussion concludes the review of government regulations on Page 544. Some brief comments can now be provided for other countries. In South America, aerosol products are often regarded as dangerous commodities to be closely controlled. Brazil, for instance, requires both the product and the manufacturing facility to be registered under the Brazilian Sanitary Vigilance Law of 1976 (and degree of 1977). All products must be harmless to the skin, include only ingredients on positive lists and bear prescribed labeling. Product registration is also featured in Venezuela, where the requirements include providing the authorities with a technical description and justification for the product, as well as a statement of ingredients and copies of any planned advertising. As in all Latin American countries, the Venezuelan government merely recommends that chlorofluorocarbon (CFC) propellents not be used. But there are no restrictions on their uses, as there are in the U.S.A., Canada and the EEC group of countries in Europe. It is inappropriate to discuss the aerosol regulations in Japan, since they are presently (1982) being recon- PETERSON/PURITAN, Inc. P/P OWNED WAREHOUSE CONTROL SPECIFIC PROCEDURE FOR QUARTERLY OR ANNUAL INTERNAL GMP AUDIT METHOD NO. 8 I PAGE 2 of 2 10. Do rest rooms have hot and cold water, soap or detergent, air driers or single-service towels and clean toilet facilities? Are they easily accessible? 11. Are outside warehouses and auxiliary buildings checked for clean and sanitary conditions? 12. Are there written procedures assigning responsibility for sanitation and describing cleaning schedules, methods and equipment—and are they available and followed? 13. Is the building in a good state of repair? No porous floors or peeling paint. No roof leakages? 14. Are there sanitation procedures for controlling microorganisms? 15. Are drains periodically cleaned and is there a procedure and assignment of responsibility for this activity? 16. Are there procedures to control insects? {Screen doors, lack of exterior wall openings for pipes, etc.) The forms reproduced on pages 480-484 are useful in keeping internal records. RETAINER SAMPLES Product: Size: Run No: Code No: Date: Filler: YOUR COMPANY NAME kYOUR ADDRESS CITY. STATE. ZIP CODE II Figure 40. Label for Retainer Samples sidered and some very major and sweeping changes will probably be made by the end of 1983. A recitation of several of their key present regulations is presented in the Aerosol Toxicity chapter, but many of these may be revised shortly.
485 TEST METHODS REVISED FLAMMABILITY TEST METHODS FOR AEROSOL PRODUCTS Recommendations of Subcommittee on Consumer Hazards and Safety Aerosol Division of CSMA 1. Abandon the Open Drum Test as a meaningful guide in establishing flammability hazards. 2. The following changes and modifications in the Flame Projection Test, Tagliabue Open-Cup Flash Point Test, and Closed Drum Test: Flame Projection Test 1. Equipment required. The test equipment consists of a base 8 inches wide, 2 feet long, marked in 6 inch intervals. A rule 2 feet long and marked in inches is supported horizontally on the side of the base and about 6 inches above it. A paraffin candle approximately 1 inch in diameter and of such height that the top third of the flame is at the height of the horizontal rule, is placed at the zero point in the base. 2. Procedure. The test is conducted in a draft-free area that can be ventilated and cleared after each test. Condition the dispenser to 70° ± 1° F. Shake the dispenser before test. Hold the dispenser upright unless label states otherwise. Place the dispenser at a distance of 6 inches from the flame source. Spray for 4 seconds (one observer noting the extension of the flame and the other operating the dispenser) through the top third of the flame and essentially parallel to the rule. The height of the flame should be approximately 2 inches. The normal bending of the flame is part of the recorded distance. Take 3 readings for each test and average. As a precaution do not spray large quantities in a small, confined space. Free space of previously discharged material. Tagliabue Open-Cup Flash Point Test 1. Equipment. ASTM Designation: D 1310-55T. Issued 1954; Revised 1955. "Flash Point of Volatile Flammable Materials by Tag Open-Cup Apparatus". The apparatus proposed for use is the new Tag Fischer open-cup flash point apparatus, with the addition of some means, preferably an open type of vessel to contain dry ice, to chill the aerosol unit. 2. Procedure. The aerosol unit, filled as for use, is chilled to a temperature of about 25° F. below zero and 14
486 also the flash cup and the bath solution (brine or glycol). The chilled formulation is transferred to the test apparatus and the cup filled to the conventional level using the mechanical leveling device furnished with the apparatus. The test liquid is allowed or caused to increase in temperature at a rate of about 2° F. per minute and the test flame taper passed across the cup at intervals of 2° F. until the sample reaches +20° F. or until the test sample has evaporated completely. This procedure is not applicable to products in which the presence of a solid portion prevents the transfer of a uniform sample to the cup at —25° F. Closed Drum Test 1. Equipment required. The apparatus consists of a 55-gallon open head drum which has been modified as follows: (1) a closure is fitted over the open head (see note No. i); (2) a circular opening 1 inch in diameter is bored through the base, about 2 inches from the edge, in such a position that when the drum is on its side the hole will be at the top. (3) a metal base 9 inches long, 2 inches wide and at least 1/16 inch thick is used as a candle support (see drawing above); (4) a paraffin candle approximately 1 inch in diameter and at least 3 inches in height; (5) optionally a 6-inch square opening is cut through the center of the base of the drum and securely covered with a piece of safety glass. 2. Procedure. Lay the modified drum on its side under conditions where the temperature is between 60° and 80° F., but preferentially as close to 70° F. as possible. Stand a paraffin candle in the drum on a special metal base half-way from each end of the drum. (See drawing above) Condition the dispenser to 70° ± 1° F. Light the candle on the base and secure closure. (When the film closure is used the candle should be ignited by means of a taper through the 1 inch circular opening). Shake the dispenser and hold upright or, if necessary, in such a position that the liquid contents can be sprayed directly into the drum. As quickly as possible place the dispenser at the one-inch opening and spray into the drum, directing the spray toward the center of the opposite end until an explosion takes place, or for a period up to 60 seconds, whichever occurs first. After each test, open the drum to clear the atmosphere. Clean the drum of any residues which might affect future tests. Repeat the test twice as before using the same dispenser if possible. If size limitations make it necessary to use more than one dispenser, then not more than one dispenser shall be used in the performance of any one test. The results of three tests are averaged. Note 1. A hinged lid or a 16. mil thickness polyamide film can be used as the closure. Polyamide Film: The film is stretched over the open end of the drum and held in place by a strong rubber band, that CANDLE BASE HINGED LID will stretch one inch when a one pound weight is hung from its lowest point, when around the drum. A one-inch slit is cut vertically in the film beginning at a point 2 inches from the top of the drum. The polyamide film must be drawn taut over the opening TENTATIVE METHOD FOR DETERMINING THE RELATIVE FLAMMABILITY OF AEROSOL FOAM PRODUCTS Introduction Flammability is one of the more important criteria of an aerosol product. The Flame Propagation and Closed Drum Test procedures, which work so well with most aerosols, cannot be made to reliably assess the flammability of those products which are dispensed as stable foams. The present method is designed to fill this void. Foam products may be sprayed or extruded. They may be of the stable type, semi-stable variety or quick-breaking compositions. Flammability may be brought about through the use of sufficient quantities of flammable or combustible liquids, flammable propellents, or both at once. It is because of these variations that no single method has appeared to be suitable for all foam products. Rather, a dualistic method, based upon two complementary procedures, is required. The first of these procedures, known as the "Tower Test," is used to assess the rate at which a fixed volume of foam, with a specified surface area, can generate gas; and whether this gas is capable of forming a flammable mixture with air. In the second procedure, the "Trough Test," a flame is touched to the foam surface to determine if the composition is capable of flashing or sustaining a fire. Apparatus 1. Apparatus for the Tower Method: The dimensions and other specifications are provided in FIGURE ONE. The equipment consists of a base section, designed to hold a measured amount of product, over which is fitted a cylindrical chimney pierced with a vertical row of small
Test Methods holes. The suggested material is aluminum, although brass and stainless steel have also been used. 2. Apparatus for the Trough Method: The dimensions and other specifications are provided in FIGURE TWO. The equipment consists of a simple flat trough, preferably formed from stainless steel sheet, of about No. 16 Gage (0.062") thickness. Procedure for the Tower Method 1. The aerosol can is brought to equilibrium temperature by holding for at least 45 minutes in a water bath at 70° F. Tests are run for each of two "use conditions." The first test is conducted on a new can, and the second test on the same can after it has been discharged to 20% of the stated net weight of the contents of the can plus the weight of one test cupful of product. If there is insufficient material in one can for both tests, two different cans for each test may be used. In order to more nearly reproduce "use conditions," tests are not conducted on the partially used cans until one hour after the cans have been discharged. Cans should be kept at room temperature (70° F.). 2. The sample can is shaken briefly and then discharged in the normal use position into the test cup. Care should be exercised when charging the test cup so that the air pockets are not occluded by the foam, thereby reducing the apparent volume of test material used. An adapter can be used to facilitate charging the test cup with foam. 3. When the foam sample is in the test cup, allow five to ten seconds, counted from the time the cup has been filled, for the foam to expand fully before proceeding to the next step. 4. Level the foam by drawing a spatula across the top of the test cup. 5. The tower unit, with a single length of strippable tape adjusted to seal its apertures, is set in place over the foam filled cup. 6. The apparatus is left undisturbed in a draft-free area for a five-minute holding time before proceeding to the test measurement. 7. After the five-minute holding time, and again without moving the apparatus, the protective tape is stripped from the touchholes at a uniform rate so that each hole is exposed at two-second intervals. 8. As each touchhole is exposed, starting from the top ^15 hole, the flame of a small lighted gas jet is brought to the aperture. The flame should just touch the metal at the lower edge of the hole. Do not insert the flame into the hole. Figure 1. Apparatus for Tower Method Procedure for the Trough Method 1. The test samples used for this procedure are the same samples that are used for the Tower Test. The flame propagation tests are run in between the two sets of tower tests; i.e. after the intial tests, but before the cans have been discharged to 20% of the stated net weight of the contents of the can plus the weight of one cupful of product. 2. The aerosol can is brought to equilibrium in a water bath at 70° F. 3. The sample foam is shaken briefly and then discharged into the test trough. Care should be taken when charging the test trough, so that air pockets are not occluded by the foam, thereby reducing the apparent volume of the test material used. 4. When the trough has been filled, allow the foam to expand for five seconds before proceeding to the next step. 5. Quickly draw the edge of a large spatula across the top of the trough to level the foam. 9. A positive result is indicated when a flash occurs in the tube, and the hole number from where the flash occurs is recorded. Reported results should be the average of three tests for each sample. 6. Three tests are conducted for each foam sample. The first test, immediately after the foam has been leveled in the trough; the second test, after a two-minute holding
488 The Aerosol Handbook Figure 2. Apparatus for Trough Method time; and the third, after a five-minute holding time. The trough is left undisturbed and in a draft-free area for the designated holding times between tests. 7. At the end of the holding time, a small lighted gas flame is brought to the surface of the foam in the area to one-half inch from the end of the trough. 8. A positive test is indicated when the flame is sustained or propagated by the propellent gas or foam material after withdrawal of the flame. Presentation of test results A positive result for the Tower Test is reported as the average of three tests for each product. For example: Test No. 1 Positive; at hole number 7. Test No. 2 Positive; at hole number 9. Test No. 3 Positive; at hole number 6 Average: Positive. Hole number 7. A positive result for the Trough Test should be reported in terms of these observations: P Indicates propagation of flame. 12 Depicts distance of travel in inches. SM Indicates flame is sustained on surface. RT Shows flame is not sustained, but travels to end of trough and returns toward the starting point. Numbers may be added to indicate number of inches on return. Typical positive results might then be recorded as: P-3 Showing that the flame traveled three inches toward the far end of the trough and then went out. P-14/RT-7 Indicating that the flame traveled to the far end of the trough and then returned about halfway back before extinguishing itself. P-l 4/SM Flame travels across trough and continues to burn. These typical results of each test can be compared as follows: Tower Test: Touchhole No. 9 indicates a product more flammable than Touchhole No. 6 Trough Test: P-14/SM is worse than P-14/RT-7 which, in turn, is more flammable than P-3 Discussion Because of the difficulty in relating the results of these tests to the degree of hazard involved in the transportation, warehousing or end uses of these foam type products, the two procedures are not to be used in order to determine if a product is to be called "Flammable" as distinguished from "Non-flammable." They are presented simply as the means by which the relative flammability of foam products may be assessed. The procedures have been most thoroughly evaluated on simple shaving cream aerosols, and are certified only for application to this particular product type. In addition, the methods have been applied to a variety of stable foam items, such as upholstery cleaner, charcoal lighter, metal polish and hair shampoo, with good results. The procedures have not been evaluated with thermal foams, foaming gels, quick-breaking foams, anhydrous foams and reticulated gels; so that any conclusions made concerning the relative flammability of these products must be made according to the investigator's own recognizance. FLASH POINT DETERMINATION Excerpts from Regulations Issued For The Federal Hazardous Substances Act (1) Extremely flammable and flammable contents of self-pressurized containers — (1) Extremely flammable contents. Contents of self-pressurized containers are "extremely flammable" if when tested by the method prescribed in f 191.15, flashback (a flame extending back to the dispenser) is obtained at any degree of valve opening and the flashpoint, when tested by the method described in 1191.16, is less than 20° F. (2) Flammable contents. Contents of self-pressurized containers are "flammable" if when tested by the method described in f 191.15 a flame projection exceeding 18 inches is obtained at full valve opening or a flashback (a flame extending back to the dispenser) is obtained at any degree of valve opening. (m) Substances that generate pressure. A substance is hazardous because it "generates pressure through decomposition, heat, or other means" if: (1) It explodes when subjected to an electrical spark, or to percussion, or to the flame of a burning paraffin candle for 5 seconds or less; or
Test Methods 489 (2) It expels the closure of its container, or bursts its container, when held at or below 130° F. for 2 days or less; or (3) It erupts from its opened container at a temperature of 130°F. or less, after having been held in the closed container at 130°F. for 2 days. (4) If it comprises the contents of a self-pressurized container fl91.13 Tentative method of test for flashpoint of volatile flammable materials by Tagliabue open-cup apparatus1 >2 Scope 1. (a) This method describes a test procedure for the determination of open-cup flashpoints of volatile flammable materials having flashpoints below 175° F. (b) This method, when applied to paints and resin solutions which tend to skin over or which are very viscous, gives less reproducible results than when applied to solvents. Outline of Method 2. The sample is placed in the cup of a Tag Open Tester, and heated at a slow but constant rate. A small test flame is passed at a uniform rate across the cup at specified intervals. The flashpoint is taken as the lowest temperature at which application of the test flame causes the vapor at the surface of the liquid to flash, that is, ignite but not continue to burn. Apparatus 3. The Tag open-cup tester is illustrated in Fig. 1. It consists of the following parts, which must conform to the dimensions shown, and have the additional characteristics as noted: (a) Copper bath, preferably equipped with a constant level overflow so placed as to maintain the bath liquid level 1/8 inch below the rim of the glass cup. (b) Thermometer holder. Support firmly with ringstand and clamp. (c) Thermometer. For flashpoints above 40° F., use the ASTM Tag Closed Tester Thermometer, range of +20 to +230° F., in 1° F. divisions, and conforming to thermometer 9F. of ASTM Standard E 1. For flashpoints below 20° F., use ASTM Thermometer 33F. The original Tag Open-Cut (Paper Scale) Thermometer will be a permissible alternate unit January 1, 1962. It is calibrated to -20° F. The Food and Drug Administration has obtained permission from the American Society for Testing Materials, Philadelphia, Pa., to reprint this method in these regulations. The text has been slightly modified, for practical reasons. 2ASTM Designation: D 1310-59T, issued 1954; revised 1955,1956,1959.This tentative method has been approved by the sponsoring committee and accepted by the American Society for Testing Materials in accordance with established procedures, for use pending adoption as standard. Suggestions for revisions should be addressed to the Society at 1916 Race St., Philadelphia, Pa. ~V=CD Figure 1 (d) Glass test cup. Glass test cup (Fig. 2), of molded clear glass, annealed, heat-resistant, and free from surface defects. (e) Leveling device. Leveling device or guide, for proper adjustment of the liquid level in the cup (Fig. 3). This shall be made of No. 18-gage polished aluminum, with a projection for adjusting the liquid level when the sample is Figure 2
The Aerosol Handbook -to __L 3~T FIGURE 3 — Leveling device for adjusting liquid level in test cup. added to exactly 1/8 inch below the level of the edge or rim of the cup. (0 "Micro," or small gas burner of suitable dimensions for heating the bath. A screw clamp may be used to help regulate the gas. A small electric heater may be used. (g) Ignition taper, which is a small straight, blow-pipe type gas burner. The test flame torch prescribed in the method of test for flash and fire points by Cleveland Open Cup (ASTM designation: D 92) is satisfactory. (h) Alternative methods for maintaining the ignition taper in a fixed horizontal plane above the liquid may be used, as follows: (1) Guide wire, 3/32-inch in diameter and 3 1/2 inches in length, with a right-angle bend 1/2-inch from each end. This wire is placed snugly in holes drilled in the rim of the bath, so that the guide wire is 5/8-inch from the center of the cup and resting on the rim of the cup. (2) Swivel-type taper holder, such as is used in ASTM METHOD D92. The height and position of the taper are fixed by adjusting the holder on a suitable ringstand support adjacent to the flash cup. (i) Draft shield, consisting of two rectangular sheets of noncombustible material, 24 inches x 28 inches, are fastened together along the 28-inch side, preferably by hinges. A triangular sheet, 24 inches x 24 inches x 34 inches is fastened by hinges to one of the lateral sheets (to form a top when shield is open). The interior of the draft shield shall be painted a flat black. Procedure 4. (a) Place the tester on a solid table free of vibration, in a location free of perceptible draft, and in a dim light. (b) Run water, brine, or water-glycol solution into the bath to a predetermined level, which will fill the bath to 1/8-inch below the top when the cup is in place. An overflow is permissible for water-level control. Standardization 8. (a) Make determinations in triplicate on the flashpoint of standard paraxylene and of standard isopropyl alcohol which meet the following specifications: (i) Specifications for p-xylene, flashpoint check grade. p-Xylene shall conform to the following requirements: Specify gravity: 15.56° C./15.56° C, 0.860 minimum, 0.866 maximum. Boiling range: 2° C. maximum from start to dry point when tested in accordance with the method of test for distillation of industrial aromatic hydrocarbons (ASTM designation: D 850), or the method of test for distillation range of lacquer solvents and diluents (ASTM designation: D 1078). The range shall include the boiling point of pure p-xylene, which is 138.35° C. (281.03° F.). Purity: 95 percent minimum, calculated in accordance with the method of test for determination of purity from freezing points of high-purity compounds (ASTM designation: D 1016), from the experimentally determined freezing point, measured by the method of test for measurement of freezing points of high-purity compounds for evaluation of purity (ASTM designation: D 1015). (ii) Specifications for isopropanol, flashpoint check grade. Isopropanol shall conform to the following requirements: Specific gravity: 0.8175 to 0.8185 at 20° C./20° C. as determined by means of a calibrated pycnometer. Distillation range: Shall entirely distill within a 1.0° C. range which shall include the temperature 80.4° C. as determined by ASTM method D 1078. Average these values for each compound. If the difference between the values for these two compounds is less than 15° F. (8.5° C.) or more than 27° F. (16° C), repeat the determination or obtain fresh standards. (b) Calculate a correction factor as follows: X = 92-A Y=71 -B Correction = 2 Where: A = Observed flash of p-xylene, and B = Observed flash of isopropyl alcohol. Apply this correction of all determinations. Half units in correction shall be discarded. Precision 9. (a) For hydrocarbon solvents having flashpoints between 60° F. and 110° F., repeatability is ±2° F. and the reproducibility is 5° F. (b) If results from two tests differ by more than 10° F., they shall be considered uncertain and should be checked. The calibration procedure provided in this method will cancel out the effect of barometric pressure if calibration and tests are run at the same pressure. Data supporting the precision are given in Appendix III of the 1956 Report of Committee D-l on Paint, Varnish, Lacquers and Related Products, Proceedings, Am. Soc. Testing Mats., Vol. 56 (1956). fl91.14 Method for determining extremely flammable and flammable solids. (a) Preparation of sample —(1) Granules, powders, and pastes. Pack the sample into a fiat, rectangular metal boat with inner dimensions 6 inches long x 1 inch wide x one-fourth inch deep.
Test Methods 491 (2) Rigid and pliable solids. Measure the dimensions of the sample and support it by means of metal ringstands, clamps, rings, or other suitable devices as needed, so that the major axis is oriented horizontally and the maximum surface is freely exposed to the atmosphere. (b) Procedure. Place the prepared sample in a draft-free area that can be ventilated and cleared after each test. The temperature of the sample at the time of testing shall be between 68° F. and 86° F. Hold a burning paraffin candle whose diameter is at least 1 inch, so that the flame is in contact with the surface of the sample at the end of the major axis for 5 seconds or until the sample ignites, whichever is less. Remove the candle. By means of a stopwatch, determine the time of combustion with self-sustained flame. Do not exceed 60 seconds. Extinguish flame with a CO2 or similar non-destructive type extinguisher. Measure the dimensions of the burnt area and calculate the rate of burning along the major axis of the sample. (c) Firmly support the thermometer vertically halfway between the center and edge of the cup on a diameter at right angles to the guide wire, or on a diameter passing through the center of the cup and the pivot of the taper. Place so that the bottom of the bulb is 1/4-inch from the inner bottom surface of the cup. If the old Tagliabue thermometer is used, immerse to well cover the mercury bulb, but not the wide body of the thermometer. (d) Fill the glass cup with the sample liquid to a depth just 1/8-inch below the edge, as determined by the leveling device. (e) Place the guide wire or swivel device in position, and set the draft shield around the tester so that the sides form right angles with each other and the tester is well toward the back of the shield. (0 If a guide wire is used, the taper, when passed, should rest lightly on the wire, with the end of the jet burner just clear of the edge of the guide wire. If the swivel-type holder is used, the horizontal and vertical positions of the jet are so adjusted that the jet passes on the circumference of a circle, having a radius of at least 6 inches, across the center of the cup, at right angles to the diameter passing through the thermometer, and in a plane 1/8-inch above the upper edge of the cup. The taper should be kept in the "off position, at one end or the other of the swing, except when the flame is applied. (g) Light the ignition flame and adjust it to form a flame of spherical form matching in size the 5 32-inch sphere on the apparatus. (h) Adjust heater source under bath so that the temperature of the sample increases at a rate of 2 ±0.5° F. per minute. With viscous materials this rate of heating cannot always be obtained. Initial Test 5. Determine an approximate flashpoint by passing the taper flame across the sample at intervals of 2° F. Each pass must be in one direction only. The time required to pass the ignition flame across the surface of the sample should be 1 second. Remove bubbles from the surface of the sample liquid before starting a determination. Meticulous attention to all details relating to the taper, size of taper flame, and rate of passing the taper is necessary for good results. When determining the flashpoint of viscous liquids and those liquids that tend to form a film of polymer, etc., on the surface, the surface film should be disturbed mechanically each time before the taper flame is passed. Recorded Tests 6. Repeat the procedure by cooling a fresh portion of the sample, the glass cup, the bath solution, and the thermometer at least 20° F. below the approximate flashpoint. Resume heating, and pass the taper flame across the sample at two intervals of 5° F. and then at intervals of 2° F. until the flashpoint occurs. Reporting Data 7. The average of not less than three recorded tests, other than the initial test, shall be used in determining the flashpoint and flammability of the substance. fl91.15 Method for determining extremely flammable and flammable contents of self-pressurized containers (a) Equipment required. The test equipment consists of a base 8 inches wide, 2 feet long, marked in 6-inch intervals. A rule 2 feet long and marked in inches is supported horizontally on the side of the base and about 6 inches above it. A paraffin candle 1 inch or more in diameter, and of such height that the top third of the flame is at the height of the horizontal rule, is placed at the zero point in the base. (b) Procedure. The test is conducted in a draft-free area that can be ventilated and cleared after each test. Place the self-pressurized container at a distance of 6 inches from the flame source. Spray for periods of 15 seconds to 20 seconds (one observer noting the extension of the flame and the other operating the container) through the top third of the flame and at a right angle to the flame. The height of the flame should be approximately 2 inches. Take three readings for each test, and average. As a precaution do not spray large quantities in a small, confined space'. Free space of previously discharged material. fl91.16 Method for determining flashpoint of extremely flammable contents of self-pressurized containers The apparatus used is the Tagliabue Open-Cup Flashpoint Apparatus as described in f 191.13. Some means such as dry ice in an open container is used to chill the pressurized container. The container, the flash cup, and the bath solution of the apparatus (brine or glycol may be used) are chilled to a temperature of about 25° F. below zero. The chilled container is punctured to exhaust the propellant. The chilled formulation is transferred to the test apparatus and tested in accordance with the method described in 1191.13. CSMA NOTE: This test is taken from ASTM Designation D-1310-SST Issued 1954; revised 1955. "Flash Point Volatile Flammable Materials by Tag Open-cup Apparatus". The test is considered to terminate when the sample flashes, reaches +20° F. or evaporates completely.
492 The Aerosol Handbook "A-D" VALVE DIMENSION TENTATIVE METHOD FOR MEASURING " A I-»" A-D" DIMENSION OF AEROSOL CAN VALVES INTRODUCTION A simple device is presented for the routine measurement of the "A-D" valve dimension. This distance is defined as the standard for stipulating dip tube depth. It is the centerline dimension from the top plane of the mounting cup curl to the far end of the diptube; (Figure 1). For quality control purposes it is desirable to have a method available for the rapid measurement of dip tube depth. This is especially important where large numbers of measurements must be taken. The present device eliminates cumbersome hand manipulations, parallax errors and similar difficulties. It provides a means for measuring dip tube depths with excellent accuracy at speeds of from about 10 to 14 per minute. METHOD The measuring guage is produced from an aluminum cylinder machined to a length of 8.717' and an outside diameter of 1.216". A complete description is given in the accompanying drawing; (Figure II). This is for a left-handed guage. A right-handed one may be produced by machining a mirror-image of the gauge bar itself and locating the ruler on the opposite quadrant flat. For individual accurate "A-D" measurements the valve is inserted so that the dip tube slides down the centerbore of the gauge. With the mounting cup held snugly in place against the gauge end, the exact dip tube depth is read off the steel rule. For repetitive or quality control measurements the valve is inserted as before, using a gauge where the steel rule has been temporarily marked in pencil to show the tolerance or range of acceptance. Each valve may then be rapidly checked to show compliance with the "A-D" specification. The pencil marks may then be removed by hand rubbing. Do not use ball point pens or other marking devices where the lines will have to be removed with solvent or abrasive. This can also remove the black lettering and line fillers of the ruler itself, rendering it much harder to read. With only a slight loss in accuracy the tolerance marks may be made upon the opposite quadrant flat. For some operations permanent marks may be scribed on this flat with a suitable tool. DISCUSSION The true measure of dip tube depth is a function of the depth of protrusion into the aerosol can. This will be Figure 1. "A—D" Valve Dimension affected by relativt dip iuoo ;nrvatures and by variations in the ratio of can diameter to total height — factors which cannot be anticipated by any simple gauging device. The present measurement compensates for variations in cup depth, cup contour, body length and upper reference position of the dip tube. Operations such as crimping the valve and pressurizing the aerosol container will shorten the "A-D" dimension slightly, but these effects are fairly reproduceable and compensations could be made if necessary. If the steel ruler is attached to the gauge bar with a high degree of precision, the device may be expected to function with an accuracy of about ±0.012". Where the ruler is attached with a metal adhesive, the inset end of the gauge bar should end at 0.033" by extension of the cut offend of the ruler. If it is too long the end should be machined down. Where the ruler is attached by means of several screws, it is desirable to use roundhead machine screws, set through holes in the ruler large enough to allow for precise positioning of the scale before final tightening. Only one assumption is made in the construction of the gauge: that the vertical distance through the curl of the mounting cup, including the thickness of the cup gasket, totals 0.0333". Studies made with an Ames No. S-4469 dial micrometer or comparable equipment will show that this crown dimension usually holds true to within about ±0.004" on a 2-sigma or 95% confidence level. The variation is due mainly to differences in cup gasket thickness. It is not possible for the average operator to read the ruler this accurately; normal reproduceability being about ±0.0065" with a perfectly sheared dip tube. The variation may be neglected for all practical purposes. rr 11 t """i .._. fi* fmmm/MMMMM£MMWMW/M i i ~j Figure 2. Measuring Gauge
Test Methods The average dip tube is not cut off at precisely a right angle, nor is the cut end smooth and free from imperfections. Often the center-line distance from the short sector to the long sector is as much as 0.006". The slight residual curvature of the dip tube, as it reposes within the gauge bar, may require the averaging of high and low readings on the oblique surface. Polyethylenes stretch easily and should never be straightened with any method which involves tension. Polypropylenes and nylon dip tubes are less easily stretched. The distortional effects of valve crimping and can pressurization have been mentioned. Hot tanking also produces an irreversible distortion of about 0.0025". To these vectors are added the swelling effect of the aerosol formula and the consideration that the cut end of the dip tube is never horizontal, but slanted towards a point on the bottom chime of the container. From all this it is apparent that dip tube measurements with accuracies better than +0.016" serve no real purpose in quality control operations. The usual specification for dip tube depth is supplied by valve manufacturers at L+0.063". A gauge bar has several applicational limitations. It cannot be used to provide an accurate "A-D" measurement for ferrule type valves*, co-dispensing valves, extra-large dosage metering valves, or those with unusual mounting cup designs, such as the turret-top styles. Double dip-tube valves and those with dip tubes having an outside diameter greater than about 0.242" cannot be handled. The "A-D" dimension itself is often found to be inapplicable to these unique valves. CREDITS The Modern Machine Shop, Inc., at 123 North Hazel Street, Danville, Illinois 61832, has had experience in the manufacture of a number of these gauge bars and may, therefore, be considered as a reliable source. We are indebted to the British Aerosol Manufacturers Association (BAMA) and the Federation of European Aerosol Associations (FEA) for providing the original idea for the construction of this instrument. ALTERNATE DEVICE FOR MEASURING THE DIP TUBE DEPTH OF AEROSOL VALVES This device consists basically of 3 machined parts made of plexiglas. In addition, there is a scale glued to the "scale block"; a foam bottom pad may be added for non-slip characteristics. The valve to be measured is inserted into the device, placing the actuator/stem end to the higher end of the device. The slide bar is then pushed firmly to the left to "seat" the mounting cup against base end. The reading may then be taken off the scale at the end of the dip tube, giving the "A-D dimension" from top of mounting cup to dip tube end. Note that this measuring device can be used to measure valves of various types, including ferrule-type valves. It would not be applicable to co-dispensing or large-tank metered valves; undue distortion would occur with double dip tube valves or large O.D. dip tubes. *Reference is made to an attached alternative device for measuring dip tube depths. It may be used for "A-D" measurements of ferrule type valves as well as for aerosol can valves. 493 PROCEDURE FOR EVALUATION OF COMBING CHARACTERISTICS OF HAIR SPRAY FORMULATIONS (Editor's Method) SCOPE This test evaluates, subjectively, the adhesion, flaking and general effect on combing characteristics of aerosol formulations on hair. Two undesirable effects seen in some formulations on hair: 1. Flaking This condition manifests itself in the appearance of small polymer particles distributed throughout the hair. 2. Snarling This appears to be due to general tackiness or, conversely, extreme brittleness. In the case of brittle polymers, the resin ruptures during combing and produces small barbs of polymer protruding from the hair shafts. Both the tacky and brittle polymers resist combing and increase the possibility of entanglement of individual hair shafts. PROCEDURE 1. Ten inch hair swatches are prepared according to the description given in the "Curl Retention Procedure". 2. All testing; i.e., spraying, drying and combing is performed at 72°F./50RH and run on three swatches for each formulation. 3. The test formulation is applied to a rotating (20 RPM) hair swatch by a 5-second aerosol discharge at a distance of 7 inches. 4. The swatch is allowed to dry, undisturbed, for 30 minutes. 5. Comb the length of the hair piece 5 times (at a rate of 3"/second) with the fine teeth of a comb (13-7/8" teeth/inch): Record evaluations. 6. Repeat steps 3 to 5 until the formulations under test show severe flaking or are difficult to comb. 7. Perform test on 3 swatches for each formulation variable. EVALUATION A. Combing Rating None to slight resistance to combing — 1 Moderate resistance distributed at different points along length of hair —2 Moderate to severe resistance throughout length of of hair —3
494 The Aerosol Handbook Definite snarling of hair, resisting combing at different points along length of hair Definite snarling of hair throughout length of hair, completely resisting combing -4 -5 B. Microscopic Examination Rating Good adhesion —1 Small amount of resin particles —2 Appearance of polymer fragments protruding from resin film - increased flaking (moderate) —3 A more general loss of adhesion from hair shafts —4 Severe Flaking —5 Note - With microscope ratings of 3-5 the flaking is usually apparent upon visual examination of the hair swatch without magnification. C. Flaking Rating - Visual Inspection None - very slight visible Slight Moderate Moderate - severe Severe -1 -2 -3 -4 -5 Note - Also report differences in gloss among the formulations under test. DETERMINATION OF THE HIGH HUMIDITY CURL RETENTION OF AEROSOL HAIR SPRAYS (Editor's Method) The curl retention properties of polymeric hair spray resins are measured at 90% RH over a period of three hours. The change in percentage retention versus time may be plotted to illustrate differences among formulations. The procedure lends itself to statistical analysis of formulation variables. EQUIPMENT 12" Remi, Blue String, European, brown hair Barber shears 7 1/2" nylon combs Alligator and paper clips White cotton thread, size # 8 Identification tags "Klippees" hair clips 3"x 1/2" Teflon mandrel 140° oven - Forced air Swingline binder clips Plexiglass retention board Humidity Cabinet (precision to± 2% RH at 70°F.) Motor and rheostat Shampoo (J. H. Breck) Interval timer PROCEDURE A. Preparation of Curl Swatches 1. Separate hair into small swatches of approximately 2 grams in weight. 2. Secure hair sample 1 inch from root end by winding with cotton thread. 3. Fold over at root end and secure the hair into a small loop with thread (Figure 1). Leave approximately 6 inches of loose thread to secure identification tag. 4. Wash hair swatch in a 10% solution of shampoo. Then rinse thoroughly with distilled water. 5. Comb to untangle the hair shafts. 6. Cut the hair swatch to measure 10 inches in length from the looped root end. Dry 1/2 hour at 140°F. 7. In order to prevent loss of individual hair shafts during subsequent combing, glue the root end at the thread windings with Duco cement B. Preparation and exposure of Test Samples 1. Hang a hair swatch from a motor chuck. Secure the end of the tress with a Swingline binder clip to prevent motion of the hair during spraying. The motor should be adjusted with a rheostat so that the shaft rotates at 20 RPM. 2. With the hair swatch rotating, hold the aerosol container at a distance of 7 inches and spray for 10 seconds. Direct the spray uniformly throughout the length of the tress. 3. Remove the binder clip and bring fingers gently down the full length of the hair, squeezing off any excess resin solution. 4. Comb hair twice, using the wide teeth (9-7/8" teeth/inch) of a 7 1/2" nylon comb. Roll curl on a 1/2" diameter Teflon mandrel. Remove curl from mandrel and secure with a "Klippee". 5. Dry in a 140°F oven for 30 minutes and then allow curl to condition at 72°F at 50% RH overnight. 6. Remove "Klippee" and gently bring the curl down by unwinding into a spiral with a glass rod. 7. Place the unwound curls at random on Plexiglass retention boards (Figure 2). Take initial reading. 8. Set retention boards into humidity chamber and record length of curl every 30 minutes over a period of three hours (Figure 3). C. Calculations Calculate percentage curl retention by: L-Lt Curl Retention (%) = L-Lr x 100 Where L = Length of hair fully extended Where L0 = Length of hair before exposure Where Lt = Length of hair after exposure Note - Determine retention of 10 replicates of each variable.
Test Methods 495 DETERMINATION OF THE PRESSURE (OR VACUUM) IN AN AEROSOL CONTAINER (Editor's Method) SCOPE The method is satisfactory for all aerosols having a pressure of 180 psi-g. or less, provided they have a valve to which the gauge assembly can be connected. APPARATUS Apparatus requirements will vary according to the pressure (or vacuum) in the container, the design of the aerosol valve, and the accuracy desired. Gauge assemblies should be selected in accordance with the following table: For the accurate readings the U. S. Inspector's Gauge is threaded to a coupling, then a toggle valve and finally to an adapter made to match the valve of the test unit. For less accurate readings the Inspector's Gauge may be used without the pre-pressurization assembly. For the less accurate readings a General Purpose Gauge may also be used, either with or without the pre-pressurization assembly. If pre-pressurization is not desired, connect the gauge directly to the valve adapter. In this case the gauge should be either two-inch or three-inch diameter, to minimize the size of the Bourdon tube. Individual gauges or complete assemblies may be purchased from several sources, including Builder's Sheet Metal Works, Inc., 108 Wooster Street, New York, N. Y. 10012; or General Kinetics Division, 451 Stephens Street, SW, Atlanta, Ga. 30302. The Inspector's Gauge with pre-pressurizing assembly cost about $69.29 in 1972. The General Purpose Gauge with adapter cost about $9.70 during 1972. Pressure gauges should be checked against standards on a daily basis, using pure propellent as the pressure source. A water bath, normally maintained at 70° ± 0.5°F., is required for accurate work. For less accurate studies the water bath may have a tolerance of + 1.0°F. PROCEDURE 1. Condition test container by upright immersion in water bath for 30 minutes. 2. For pre-pressurized gauges, pressurize to 2 or 3 psi. greater than anticipated test container pressure. 3. Remove container from water bath, actuate briefly, remove button or foam spout, shake for five seconds, and apply the gauge assembly firmly to the valve to get a good seal. 4. Actuate the valve by moving the gauge assembly against it. Open toggle valve and agitate assembly to bring gauge pointer to maximum reading. Tap gauge face lightly. Re-actuate several times and take the average of the readings. For best readings at elevated temperatures, leave test container in water bath while taking readings. 5. Clean out any product forced into valve system by applying gauge to a can containing a P-12/ethanol mixture. REPORTING Accurate gauge readings should be reported to the nearest ± 0.5 psi. Less accurate readings may be reported to the nearest + 1.0 psi. Test methods in this chapter supplement discussions elsewhere in this text. The reader is referred also to the CSMA Aerosol Guide, Seventh Edition, 1981. Type of Gauge Inspector's General Purpose ♦ Inspector's General Purpose Inspector's General Purpose Inspector's General Purpose Gauge Pressure Range; psi-g 0" to 30" Hg° 0" to 30" Hg° 0 to 60 0to60 Oto 160 0 to 160 0 to 300 0 to 300 Pressure Range Required Accurate Determination; psi-g. 0" to 30" Hg° Oto 40 30 to 100 80 to 180 Less Accurate Determination; psi-g. 0" to 30" Hg0** 0" to 30" Hg° Oto 40** 30 to 60 30 to 100** 30 to 160 60 to 180** 60 to 300 ♦General Purpose Gauges may be used with or without the pre-pressurization assembly. •"♦Inspector's Gauge is used without the pre-pressurization assembly.
496 The Aerosol Handbook FORM I FURNITURE POLISH EVALUATION INDIVIDUAL RATINGS FOR 4.3 Properties - — - TEST PANEL APPLICA TION NO. 1 Left Center — - - • Right TEST PANEL APPLICA TION NO. 2 Left —- Center - - - - Right - - _ ----- - - - . Properties TEST PANEL APPLICATION NO. 3 Left Center Right TEST PANEL APPLICA TION NO. 4 Left Center Right idling ouue. u-j N0TE. Designate position of product (X or C) in box 5 -Excellent 3 - Good 1 -Poor designating position on test panel; i.e., Left, Center, or 4 - Very Good 2 - Fair 0 - Complete Failure Right.
Test Methods 497 TENTATIVE METHOD FOR FURNITURE POLISH EVALUATION Subcommittee B (R. J. Thimineur, Chairman) of the Scientific Committee of the Waxes, Polishes and Floor Finishes Division, (C.S.M.A.) approved the following method in New York City, December, 1970. 1. Functional Definition 1.1 A furniture polish aids in cleaning, improving the appearance, and protecting the furniture finish from such common damaging effects as finger marking, food stains and other surface deposits that are commonly encountered with furniture. 2. Scope 2.1 This test method is intended to define the properties to be tested, the apparatus to use and the comparisons of product performance. It is recognized that considerable discretion exists among formulators and marketers of furniture polish on what properties or performance characteristics are best for their products. This test method will be flexible to honor this fact within the confines of the furniture polish definition above. 2.2 The methods of testing are subjective and empirical in order to conform to the basic characteristics of the industry and to allow flexibility in testing. 3. Apparatus and Materials 3.1 Sample of polish to be tested 3.2 Sample of control polish. The control polish is selected subjectively for comparison to the test polish. It may be a competitive product, a modified formulation of the test polish, etc. The one stipulation is that the control polish be of the same or similar type as the test polish. For example, if the test polish is an aerosol emulsion polish, the control should be an aerosol emulsion polish. It would not be meaningful to select a paste or liquid product as a control for comparison with an aerosol emulsion test polish. 3.3 Test Substrates. The test substrate should be one for which the test polish is intended. The test surface should be in good physical condition, not badly cracked, scratched, or otherwise damaged so as to interfere with evaluation of polish properties. The minimum test surface area for each sample should be 200 sq. in. 3.4 Polishing cloth. The same type of polishing cloth should be used with each sample tested. Separate cloths are to be used for each sample. Materials such as washed cheese cloth, rumple cloth, flannel, cotton diaper cloth, and non-woven fabrics are suitable for this purpose. Felt or paper should not be used. 3.5 Cleaning solvent. Aliphatic solvents with KB values less than 38. 3.6 Eye droppers and tap water. 4. Procedure 4.1 Cleaning of Test Substrates. An aliphatic solvent having a KB value less than 38 should be used to clean the test substrate thoroughly. Paper towels may be used to apply the solvent to the surface and to wipe it clean. New towels should be used each time. 4.2 Application of Polish. Assuming the control polish or the test polish is a commercially available product, follow the directions on the container so far as is possible. When in doubt on the method of use, the directions for similar products may be used. Equal volumes of control and test polish should be used to avoid excessively thin or heavy coats of polish. One or two applications may be used depending on the substrate and the discretion of the tester. The same number of coats must be used for both the test polish and the control polish. 4.3 Placement of Polishes. A controlled randomized method of laying out the test (x) and control (c) polishes is represented as follows: Left C C X X Center X C C X Right C X X c These four positionings should be written on tags and drawn randomly by each of the four who apply the polishes Four persons are involved with the application and evaluation of the polishes. Each of the four persons take turns applying the polishes while the other three rate all properties except application properties. The persons applying the polishes rate ease of use and other application properties. This means there will be only four readings on application properties. The three rating the polishes do not observe the application because they rate properties of each polish "blind." 5. Evaluation Five minutes following the application of the polishes evaluation is begun. In each case comparison is made between the test polish and the control. All or any number of the following properties are evaluated: 5.1 Ease of Rub-Up to Maximum Gloss. During application of the polishes note the time and ease with which each product develops maximum gloss. 5.2 Gloss. Evaluated as depth of gloss. 5.3 Uniformity. Observe the surface for streaks, unpolished dry spots and general uniformity. 5.4 Film Clarity. Observe the clearnessor sharpnessof an object's image in the polished surface. Overhead lights,
498 The Aerosol Handbook face, hand, or other objects may be used for reflection. 1'his test may be eliminated for low luster surfaces that do not possess mirror-like finishes. 5.5 Smear and Mar Resistance. Smear is the degree of oiliness or greasiness after the polish is rubbed-up to the desired polish appearance. Mar is the degree of film damage resulting from a glancing blow to the polish substrate. Check smear by making a design such as an "S" with one's finger. A glancing blow with one's knuckles or soft object such as a book or magazine may be used for determining the degree of mar. 5.6 Film Healing. Observe the length of time required for the smear or mar in 5.5 to disappear from the polish film. 5.7 Rebuffability. Observe the ease and completeness of repairability when the smears and mars are buffed with a polishing cloth. The amount of physical effort and length of time required is noted. 5.8 Cleaning. Observe the ease of removal of old polish films as well as common soiling materials such as dust, grease, oils, finger marks, beverage stains, etc. This may be done either in the lab or observed during actual use trials of the products. In the lab, removal of old polish may be determined by applying multiple coats (10-20 applications) and determining polish build-up. A polish showing little build-up would be rated a good cleaner for old polish. Other materials, such as greases, oils, sugar solutions, etc., should be tested on an individual basis. 5.9 Water Spotting. At least two hours after application of the polishes, place at random to the polished surfaces several spots of water about the size of a penny. Allow the water to remain on the surface for 5-minutes, 15-minutes, 30-minutes, and 1-hour. At precise intervals, blot the water with a paper towel or other absorbent material. DO NOT WIPE! Observe the presence and degree of film damage. Other materials such as milk, coffee, juice, alcoholic beverages, etc., may be used to supplement the water test. 5.10 Gloss Retention. Observe the degree of gloss of a freshly applied polish film compared to that of an aged polish film. 5.11 Dust Attraction is measured by carefully wiping the test surface to remove all dirt and dust. Place the test substrate in the place of your choice to accumulate dust. Check dust build-up on the panel after 24, 48, and 72 hours, and after one week. 6. Report 6.1 All properties should be rated 0-5. A value of 5 equals excellent and 0 equals complete failure. Values in between are various degrees between these extremes. 6.2 Form 1 should be used to record the raw data. Form II should be used to summarize and compare the raw data. The following calculation provides a rating factor for each property tested: F = Rating factor for test polish Fq = Rating factor for control polish ^property = Sum of all readings of a specific property for the test polish. ^property = Sum of all readings of a specific property for the control polish. n = Number of observations. X property p _ C property MILITARY STANDARD SAMPLING PROCEDURES MIL-STD-105D Many excellent sampling tables exist for acceptance inspection by attributes. Each of the tables differs from all others in various ways. Some emphasize selecting the plans by Acceptable Quality Level, AQL, the maximum percent defective that can be considered satisfactory as a process average; others by Average Outgoing Quality Limit, AOQL, the maximum Average Outgoing Quality, AOQ, which can be accepted. Sampling tables provide different inspection levels; single, double, and multiple types of sampling plans; and normal, tightened, and reduced degrees of inspection. Regardless of their characteristics, each set of tables possesses plans for which the Operating Characteristic, or OC, Curves and AOQ Curves have been plotted, or for which these curves may be determined. If a person keeps these curves in mind and recognizes their value, any of the tables may be used efficiently and satisfactorily. In this chapter we shall discuss the Military Standard Sampling Procedures and Tables for Inspection by Attributes, or MIL-STD-105D, the international designation of which is ABC-STD-105. These tables will be discussed, not because they are necessarily the --best" tables, but, rather, because they are gaining the widest acceptance at the present time and are representative of most all sampling plans. These standards have undergone several revisions since they were first adopted by the Department of Defense in September 1950. The present revision, MIL-STD- 105D, 29 April 1963, has been approved by the Department of Defense and is mandatory for use by the Depart-
Test Methods 499 ments of the Army, the Navy, the Air Force and the Defense Supply Agency. The large number of defense contracts awarded since the original adoption may, in large part, account for the wide acceptance of the standards by industry as well as the Government. A. Preliminary Considerations As with any sampling plan, one of the first considerations is to select the characteristic to be checked, and to provide an adequate test procedure. B. Selection of an AQL Value After the characteristic has been defined, MIL-STD 105D requires the selection of an AQL. This necessitates a classification of particular characteristic as critical, major, or minor. The usage of the particular characteristic must be known and considered with respect to the possibility and consequences of failure in assembly and use. If the characteristic is of a critical nature, a low AQL must be selected. If it is of a non-critical nature, a higher AQL would be indicated. Where a classification of characteristics has been made by specifying them as critical, major, minor, the selection of an AQL value can be greatly simplified. C. Normal, Tightened, and Reduced Inspection MIL-STD-105D provides a specific set of rules as to the use of nermal, tightened, and reduced inspection, including continuing one and switching from one to another. The following instructions are taken from MIL-STD- 105D. INITIATION OF INSPECTION. Normal inspection will be used at the start of inspection unless otherwise directed by the responsible authority. CONTINUATION OF INSPECTION. Normal, tightened or reduced inspection shall continue unchanged for each class of defects or defectives on successive lots or batches except where the switching procedures given below require a change. The switching procedures shall be applied to each class of defects or defectives independently. SWITCHING PROCEDURES NORMAL TO TIGHTENED. When normal inspec- t on is in effect, tightened inspection shall be instituted when 2 out of 5 consecutive lots or batches have been rejected on original inspection (i.e., ignoring resubmitted lots or batches for this procedure). TIGHTENED TO NORMAL. When tightened inspection is in effect, normal inspection shall be instituted when 5 consecutive lots or batches have been considered acceptable on original inspection. NORMAL TO REDUCED. When normal inspection is in effect, reduced inspection shall be instituted providing that all of the following conditions are satisfied: a. The preceding 10 lots or batches (or more, as indicated by the note to Table VIII) have been on normal inspection and none has been rejected on original inspection; and 6. The total number of defectives (or defects) in the samples from the preceding 10 lots or batches (or such other number as was used for condition ••a'" above) is equal to or less than the applicable number given in Table VIII. If double or multiple sampling is in use, all samples inspected should be included, not "•first"' samples only; and c. Production is at a steady rate; and d. Reduced inspection is considered desirable by the responsible authority. REDUCED TO NORMAL. When reduced inspection is in effect, normal inspection shall be instituted if any of the following occur on original inspection: a. A lot or batch is rejected: or 6. A lot or batch is considered acceptable under certain conditions of reduced inspection when the sampling procedure may terminate without either acceptance or rejection criteria having been met. In these circumstances, the lot or batch will be considered acceptable, but normal inspection will be reinstated starting with the next lot or batch. c. Production becomes irregular or delayed; or d. Other conditions warrant that normal inspection shall be instituted. DISCONTINUATION OF INSPECTION. In the event that 10 consecutive lots or batches remain on tightened inspection (or'such other number as may be designated by the responsible authority), inspection under the provisions of this document should be discontinued pending action to improve the quality of submitted material. It should be noted here that many of the rules established for the use of MIL-STD-105D by the Government have been modified for use in industry. The foregoing rules have often been modified or changed, but the prospective user of these plans should benefit by restating the above conditions with his own modifications to insure a definite plan for changing from one type of plan to another. D. Selection of an Inspection Level The MIL-STD-105D tables provide for varying the discriminatory power of the sampling plan bv selecting one of four special inspection levels, S-l, S-2, S-3, S-4,
500 The Aerosol Handbook or one of three general inspection levels, I, II, III. In each case the higher the number the more discriminatory the plan. The more discriminatory the plan the larger the sample size. The OC Curves and certain tabulated values for them are given. Inspection level II is usually selected. E. Single, Double, and Multiple Sampling For most AQL values and inspection levels, the user has the opportunity to select single, double, or multiple sampling. The selection of the type of sampling plan will depend upon: 1. Psychological likes and dislikes, 2. Difficulty of administering and using the various kinds of sampling, 3. Average amount of inspection required by using the various kinds of sampling, and 4. Difficulty in selecting samples. However, for any given AQL and inspection level, the OC curves will be nearly the same regardless of the kind of sampling. F. Selecting a Sampling Plan After the preceding decisions have been made, a sampling plan can be selected for any given lot when the lot size is known. A sample size code letter, dependent upon the lot size and the inspection level, is obtained from Table I. (See page 342.) The appropriate sampling plan, sample size(s) with acceptance and rejection number(s), can then be obtained from Tables II-IV. In a single sampling plan, prescribed size is drawn at characteristic checked, and determined. If the number sample is equal to or less th the lot should be accepted, found in the sample is equal to number, the lot should be rej Table II, a sample of the random from the lot, the the number of defectives of defectives found in the an the acceptance number, If the number of defectives or greater than the rejection ected. In a double or multiple sampling plan, Table III or Table IV, a first sample of the prescribed size is drawn at random from the lot, the characteristic checked, and the number of defectives determined. If the number of defectives found in the first sample is equal to or less than the first acceptance number, the lot should be accepted. If the number of defectives found in the first sample is equal to or greater than the first rejection number, the lot should be rejected. If the number of defectives found in the first sample is greater than the first acceptance number and less than the first rejection number, a second sample of the prescribed size is drawn from the lot. The characteristic is checked, and the number of defectives found in the first and second samples are accumulated. If the accumulated number of defectives is equal to or less than the second acceptance number, the lot should be accepted. If the accumulated number of defectives is equal to or greater than the second rejection number, the lot should be rejected. In multiple sampling this process is repeated until a decision is reached. It is observed that a decision is reached with one sample in single sampling, with two or less samples in double sampling, and with seven or less samples in multiple sampling. However, the size of each sample decreases as one goes from single to multiple sampling, so that, in general, a smaller average amount of inspection is necessary for multiple than for single sampling. The disposition of any defectives found in the samples will depend upon the nature and magnitude of the defect and upon the agreement made between the producer and consumer. G. An Illustrative Example Suppose we have agreed on an AQL of 1.5 °0 for a certain characteristic, a shipment of 1500 pieces is received, and we are to determine appropriate sampling plans based on general inspection level II, normal inspection. From Table I, we obtain the sample size code letter K. From Tables II, III, and IV, we obtain: Single Sampling Sample Size Ac 125 5 Re 6 Sample Number First Second Multiple Sampling Double Sampling Sample Size 80 80 Ac 2 6 R« 5 7 Sample Sample Number Size Ac Re First Second Third Fourth Fifth Sixth Seventh 32 32 32 32 32 32 32 4 5 6 7 8 9 10 H. Additional Features of MIL-STD-IQ5D Although the AQL is commonly thought of as a percent defective, it can also be interpreted as the number of defects per 100 units. The single sampling plans are particularly adaptable and have AQL values ranging from 0.010 to 1000 defects per 100 units. This permits the use of these tables where the number of defects is a better measure of quality than is the percent defective.
Test Methods 501 TIN PLATE FABRICATED AEROSOL CANS 202 Diameter 202 x 200 202x214 202x314 207.5 Diameter 207.5x413 207.5 x 509 211 Diameter 211 x 407.5 211 x413 300 Diameter 202 x 406 202 x 509 202 x 608 207.5 x 605 207.5x701 211 x510 211 x604 202 x 700 202 x 708 207.5 x 708 207.5 x713 211 x612 211 x 713 300 x 709 Dimensions included in Industry Specifications to Date: A. Inside Diameter of 1" Cup Opening. B. Outside Diameter of 1" Cup Opening. C. Height of Curl Opening above Double Seam. D. Height over Double Seam. E. Overall Height of Container. F. Height Between Double Seams. G. Thickness of Curl Around the One Inch Opening. METHOD FOR DETERMINING DELIVERY RATE OF AEROSOL PRODUCTS Introduction The delivery rate of an aerosol dispenser is determinable by measuring the quantity of material expelled through the valve in a given time. The exact duration of discharge and the temperature of the dispenser must be carefully controlled for good reproduceability. Delivery rate tests assist in evaluating one aspect of valve performance and are considered a prerequisite to both biological and storage testing. Biological and clinical tests are often made with one or two dispensers selected from a group similiar in all respects except for delivery rate. When it is desirable to select dispensers with equal delivery rates, two or three tests should be performed on each dispenser. In the case of storage tests a single delivery rate test is normally performed at each examination period to conserve the contents and extend the life of the dispenser. Equipment Water-bath, maintained at 70° ±0.5°F. (80° ±0.5° F. for insecticides, to match Peet-Grady test requirements), with a screen or perforated metal shelf one inch above the bottom of the bath. Stirrer — air or electric. Balance, one-tenth gram scale. Stop watch or electric timer. Procedure Remove the protective cover, paper label and other detachable materials from the dispenser, except the button. If a foam spout is used, remove, cut away all non-essential plastic, and replace. Activate the valve for a few seconds, remove any valve cup impingements, and weigh the dispenser to the nearest 0.05 gram. Place the dispenser on the shelf in the water bath, which is at the test temperature of 70° ± 0.1° F. Keep the dispensers in an upright position, spaced one inch apart and covered with one inch of water. Circulate the water with the mechanical stirrer. Hold for 15 minutes in the case of essentially anhydrous products and for 25 to 30 minutes for viscous or water-based formulations. Remove the dispenser. Actuate the valve for a given time (preferably 10 seconds), preferably into an exhaust hood. Dry the dispenser with a cloth or towel and use a blast of compressed air to remove moisture from the mounting cup and can seams, in the case of metal containers. Reweigh the dispenser and compute the difference in weight.
502 The Aerosol Handbook The results of each test are reported as delivery rate in grams per second and calculated as follows: Weight loss in grams Delivery Rate = 10 Seconds Repeat the above procedure if duplicate tests are made on dispensers. Discussion The reproduceability of results by this method is considered to be about +1%. Precision is about ±2%. Any air, trapped in the product and outage space, may be expected to have an elevating effect upon delivery rates. The effect decreases as the can is emptied. The rate of decrease is much more rapid for dispensers with vapor-tap valves. Even without air, minor distillation effects will occur within the dispenser as it is used up, and these will have a small depressing effect upon delivery rates. The variation in valve orifice diameters may be as high as ±10%. Because of this, delivery rates may vary as much as ±15% from can to can. Generally, the product should be shaken before any actuation. Reference should be made to label instructions. In the case of thixotropic, rheopectic and certain other emulsion types the degree of agitation will have a considerable effect upon delivery rates. The delivery rate of freshly prepared aerosols will not usually be the same as that after aging. This is due to gasket swelling, changes in elastomer hardness and other factors. NOTE: About 0.03% of sodium nitrite may be added to the water bath to prevent the minor rusting of some tinplate containers.
GOVERNMENT REGULATIONS 503 15 Man dreams: man creates. He changes his environment in search of a better life. In the beginning he became man when he began to create options beyond those provided by nature. His hopes for a better tomorrow challenge him to extend his knowledge. In the more advanced countries of the free world, where he has been oriented to the future and open to change, man has extended his basic freedoms via technology and the free enterprise system. But he continues to hope for a still better society, for his children and for their children, and this can only be brought about by constantly redirecting and refocusing technology so that the risks remain subordinate to the benefits. Technology and society work a complex weave of effects upon each other. Our society recognizes certain obvious hazards in unbridled technological progress. Yet, many of us are unaware that excessive intolerance to risk will condemn us to a retreat from technology and then to the lustreless and uncertain future of second- rate nations. The engines of consumerism, the press, special interest groups and a somewhat over-responsive government are leading us away from innovation. They are stifling technology by legislative fiat and regulation. The odds for turning aspirations into achievements grow slimmer every year, as more and more effort is required for less and less return. Risk is becoming excessively expensive as intolerance continues to escalate. The costs of product development, health and safety in the workplace, quality assurance, product liability and similar risk-related attributes of marketing are now growing at an overall rate of some 14% per year. Like all other business costs, those for risk-management are passed along to the unsuspecting consumer. Like the government, we are now spending his money for him, in the name of protection, reducing his purchasing power through inflation, and therefore his standard of living. Higher retail costs
504 The Aerosol Handbook then inevitably lead to further attacks on the business community. Until people realize the dangers of an over-benevolent society and the risk of risk avoidance, technological apathy will remain one of our most pressing national problems. An example of added cost without comparable added value can be cited in the case where a major pharmaceutical marketer developed a line of topical products, including an aerosol dispenser, all based upon a new European drug. The aerosol product alone required a pre-marketing program lasting three years, during which over 38,000 sample units were prepared in the laboratory for testing purposes. This work was required to satisfy FDA requirements. The contract filler had to apply strict Current Good Manufacturing Practices (CGMP—or, simply, GMP) as stipulated by the FDA, and this added considerably to his costs. When the product finally reached the market it sold for over three times the retail cost of a very similar cosmetic formulation. The cost of governmental regulations designed to reduce perceived or imagined risks is truly awesome: slightly over $200 billion per year, or about $3,900 per year during 1980 for an average family of four. In 1979, these added costs helped give the U.S.A. a 13% inflation rate, a 0% productivity increase and a Real GNP of-3%, after inflation. In 1980 and 1981 the figures were quite similar. Another example of regulatory costs was developed in a survey on the impact of the EPA's Toxic Substance Control Act (TSCA) on innovation in the chemical specialties industry, which includes aerosol products. The study was conducted in 1981 and predicted a 36 to 67% decline in product and formulation innovation. The testing rules under Section 4 of TSCA are now in effect, and the EPA suggests that it will now cost about $ 1 million per chemical to get their approval to market a new product. A major marketer has disagreed, stating that the mandated carcinogenic and other tests will take over three years and boost the overall cost to $2 million. Small chemical manufacturers simply cannot afford to develop new products on this basis. Those that depend heavily on such projects will either have to realign their activities or go out of business. The impact of government upon the aerosol industry has been touched upon throughout this book. The reaction of the EPA/FDA to the chlorofluorocarbon-ozone question in 1975 was a major factor leading to a business reduction of over 30%. The associated bad press and virtual elimination of television advertising has kept the industry flat ever since. Conversions to hydrocarbon propellents cost the industry an estimated $40 million at a time when severe over-capacity was acting to drive down contract filler prices to the point where profit margins nearly vanished. About 1979 the cost of money began to escalate rapidly, moving up to a prime rate of 21 % in 1981. When a contract filler purchases components and/or chemicals for a customer, his funds may be tied up for 2.4 months before payment is received. If he is fortunate enough to have access to "20% money", his cost of money wll then be 4%. By way of example, if he purchases $0.95 of materials per can and pays $0.05 per can in wages and other immediate expenses, then his cost for money will be $0.04 per can. This would be about 25 to 50% as much as his unadjusted service income. The net effect has been to cause fillers to ask marketers to order all materials except the propellent, and sometimes to offer discounts to those who can pay at the time of purchase, with minor deviations then credited or debited, according to the number of units actually produced, material gains or losses and so forth. All of these effects have caused a drastic weakening of the industry. During 1981, a capacity reduction of about 170 million units per year occurred, through the closing of two major plants and the elimination of others as a result of economics or fire. By early 1982, an additional 100 million units of capacity was eliminated. Two or more firms avoided bankruptcy by selling out to competitors. The attrition is expected to continue at least through the end of 1983. The strong recessionary characteristics of 1981 and 1982 have led to heavy borrowing from suppliers and to delayed payment of invoices (90 to 150 days) on the part of some fillers. The future viability of these firms must be regarded as uncertain. During the decade of the 1970s, the Congress of the U.S.A. turned out from 180 to 375 anti-packaging bills per year. At the start of the 80s this was down considerably. Under "Reaganomics", regulatory activities were picked up by the states at an unprecedented rate. During 1981 a total of some 55,000 state bills were introduced, of which 57% were passed into law. (The Federal government passed only 9% of their bills.) The high percentage of enactments at the state level is one of concern because many are not well considered, good quality legislation. They are then subject to regulation developments never anticipated by the law-makers. In one instance, the California State Air Resources Board
Government Regulations 505 threatened to force the replacement of hydrocarbon propellents by chlorofluorocarbon propellents on the basis that the hydrocarbons might react photochem- ically to produce smog in the Los Angeles basin. The plan was later withdrawn when industry met with the California Board late in 1981 and advised them that their basic premise was subject to several technical errors. A number of Federal agencies administer regulations that affect the aerosol industry directly. They include the following, as perhaps the most important: a. The Food and Drug Administration (FDA) i. The Food, Drug and Cosmetic Act (FDCA) ii. The Fair Packaging and Labeling Act of 1966 (FPLA) b. The Environmental Protection Agency (EPA) i. The Federal Insecticide, Fungicide and Rodenticide Act of 1947 (FIFRA) ii. The Clean Air Act of 1977 (CAA) iii. The Solid Waste Disposal Act of 1978 (SWDA) iv. The Toxic Substances Control Act of 1972 (TSCA) v. The Federal Environmental Pest Control Act (FEPCA) vi. The Resource Conservation and Recovery Act (RCRA) vii. The Clean Water Act c. The Federal Trade Commission i. The Fair Packaging and Labeling Act of 1966 (FPLA) for non-FDA products d. The Consumer Products Safety Commission (CPSC) i. The Consumer Products Safety Act of 1972 (CPSA) The Federal Hazardous Substances Act of 1961 (FHSA) The Poison Prevention Packaging Act of 1970 (PPPA) e. The Occupational Safety and Health Agency (OSHA) i. The Occupational Safety and Health Act of 1970 (OSHA) f. The Department of Transportation (DOT) g. The U.S. Department of Agriculture (USDA) h. The National Bureau of Standards — Office of Weights and Measures (Advisory) Actually, a total of 55 major regulatory agencies operate in Washington, D.C. In 1980, they produced over 77,000 pages of regulations, as promulgated in the Federal Register. Very few will ever be rescinded or nullified. A survey taken in 1981 showed that, considering all levels of government, there are about 79,000 administrative agencies, entities or functionalities, employing about 15,500,000 people, or about 14% of the nation's work force. These regulatory units often work closely with the court system, which also employs millions of people, even up to the U.S. Supreme Court, the final earthly arbiter of all legal matters. Unlike the unfettered competitive free enterprise system envisioned by Adam Smith, these figures show that Americans actually live in a very highly regulated and controlled society. The Food, Drug and Cosmetic Act The basic FDA Act has been in existence since 1906, with major amendments provided in 1938, 1962 and 1976 that have acted to increase its scope. About 25% of all consumer dollars are spent on products regulated by the agency. Aside from foods, drugs and cosmetics, the revised act provides coverage for medical devices, for room deodorizers and disinfectant sprays used in hospital settings and for aerosol products, where deliberate consumer mis-use allows them to function as drugs. An example of this last aspect is found in a recent FDA investigation of aerosol paints and coatings, used to achieve psychodelic highs by deliberate deep inhalation of the toluene and/or other solvents. The most successful aerosol food products are whipped creams and cookware release sprays. Syrups, honey, mayonnaise and other products have been test marketed in Sepro cans and are now being looked at in the new Enviro can, which uses pouch-packed citric acid solution and sodium bicarbonate to generate CO2 propellent pressure, as needed. Facilities that produce these aerosols must be registered with the FDA as food plants and are subject to GMP inspections to assure the agency that good, safe, sanitary and correct production practices are followed. The ingredients used in food type aerosols must be FDA-approved. Additives must appear on the agency's
506 The Aerosol Handbook GRAS (Generally Recognized As Safe) list. Everything that comes into contact with the food product must also be acceptable to the FDA, and may include the elements of the storage, compounding, handling and filling system, any lubricants used in that system, the aerosol dispenser components and so forth. For example, an FDA investigation developed when a new plastic, used in an aerosol valve, changed color in contact with the food product. In another case, the FDA disallowed the continued use of neoprene valve gaskets containing a trace of a thiazole derivative as a curing agent after it was identified as a possible carcinogen. Even though the supplier provided data to show that the amount of unreacted material that could be gleaned off the surface of the seat gasket and GK-45 type gasket by the products was in the order of 10 pp(quad), or a millionth of a ppm, the agency steadfastly called for its elimination. This was finally accomplished, but with considerable difficulty. Drugs, medicinals and pharmaceutical aerosols are all controlled by the FDA, against differing standards and with variable strictness. These products include vascodilators, vaporizers, dermal fungicides, burn treatments, antiseptics, oral anesthetics, contraceptive foams, antiperspirants, sunscreens, and probably such products as depilatories, breath fresheners, skin dewrinkling preparations and skin moisturizers. They amounted to about 12% of the total aerosol volume in 1981. Plants filling these products must have at least a "Type I" Drug Master File. The FDA will send interested firms a copy of their Guidelines for Drug Master Files upon request, describing the regulatory requirements in terms of paperwork to obtain a DMF Number, the plant facilities, personnel, product types to be made, operating procedures and so forth. The time required to receive a DMF Number is 3 to 6 weeks. Drugs have been officially defined (in 1938) as articles intended for use in the diagnosis, cure, mitigation, treatment or prevention of disease in man or other animals, and articles (other than food) intended to affect the structure or any function of the body of man or other animals. In contrast, a cosmetic is an article, other than soap, that is applied to the human body for cleansing, beautification, promoting attractiveness or altering appearance. These two definitions are not mutually exclusive. For instance, a fluorinated toothpaste is both a cosmetic, because it whitens teeth, and a drug because it prevents tooth decay. A personal deodorant is simply a cosmetic, but an antiperspirant, which affects a body function (perspiration) is subject to regulation by the FDA as an over-the-counter (OTC) drug. Actually, a personal deodorant and an antiperspirant may have the same formulation, with the only difference being in the label claims. In the sunscreen area, products labeled for use only as sunscreens unquestionably fall into the OTC drug category. As such, they must contain the minimum recommended amount of sunscreening ingredient (2 mg/ml for a lotion) and claim at least the minimum recommended sun protection factor (SPF) of two — indicating a blockage of 50% of the sun's ultraviolet radiation. Such screening agents must be placed in the FDA's Category I (safe) by the OTC Panel of FDA on the basis of tests such as photo-toxicity, the Ames mutagenicity procedure and so forth. For example, a popular sunscreen, 2-ethylhexyl p-dimethylaminoben- zoate, has been placed in Category I for concentrations between 1.4 to 8.0% in the final product. As of the beginning of 1982 the FDA had yet to issue a tentative final monograph as the next step in their review process of such quasi-drug items as moisturizing lotions and creams (with or without incidental sun- screening agents present), lip balms and skin softeners. The question probably will not be settled for at least five years as to whether or not they are drugs. Other issues of coverage are equally provocative. Soap products have been omitted from FDA control, but does this also apply to the new liquid soaps that captured over 7 % of the bar soap market between 1979 and 1982? Or to medicated soaps? About 1972 the agency strongly limited the use of hexachlorophene, based upon evidence that it might cause brain damage if high doses were ingested. Skin cleansing products were limited to 0.75% unless designed for hospital or prescription uses. Not more than 0.1% could be used in cosmetics and then only as a preservative. The germicide was banned for feminine hygiene sprays. The immediate result of these sanctions was to cause industry to drop this valuable and inexpensive product in favor of other ingredients. One manufacturer stated that a 3 % hexachlorophene skin cleanser had a multi- million unit per year business for over 22 years without any report of a neurotoxic reaction. But in the panic to abandon hexachlorophene his words fell upon deaf ears at both the FDA and industry. A few skin treatment products fall outside the jurisdiction of the FDA, such as insect repellent sprays and lotions. In one of these products, claims for the preven-
Government Regulations 507 tion and control of poison plant (urushiol) effects are made, on the basis of absorption of the active ingredient by hydrous zirconium (IV) oxide/carbonate, thus giving it drug overtones. In addition, the FDA banned the use of zirconium compounds in aerosols about 1972, after satisfying themselves (but not the industry) that the use of certain zirconium/aluminum chlorhydrate glycine complexes in antiperspirants might cause pulmonary problems. While privately agreeing that the ban should not relate to zirconium oxide compositions in an aerosol foam type lotion (which could hardly be inhaled) the FDA made no move to modify the ban. So in this product we have the unique situation that, if the insect repellent were to be removed, thus taking the product out of the "protective'' jurisdiction of the EPA, it would become a banned drug product under the FDA. There are about 355,000 OTC products on the U.S.A. market, and the FDA began reviewing them in 1972 to assure their safety, efficacy and proper labeling. Drug review panels, consisting of government and industry scientists and consumer representatives, have been doing this work. Panel recommendations are then analysed by the FDA's Product Evaluation Division with certain ones accepted for inclusion in the final monographs. This huge task has been ongoing since the 1970s and will probably never really come to an end. For one thing, monographs are not monolithic; they must be changed as more technology develops. Several have been delayed until further testing can be completed. Aerosol antiperspirants are by far the largest aerosol OTC drug item. Their future is uncertain, at least to a slight extent, from both a marketing standpoint and the position taken by the FDA's OTC Drug Review Panel. During 1980, OTC Review Chief William Gilbertson advised the industry that the FDA did not agree with the industry's assessment that two rather new federal studies on aluminum clorhydrate aerosol antiperspirants sufficiently established the safety of such products that they should be given Category I (safe) status. These studies involved Syrian hamsters, Fisher rats and Hartley guinea pigs, and indicated that when a lung burden 100 times that expected in an aerosol antiper- spirant user is produced in these animals the only response in the lung is an increase in the number of alveolar macrophages — precisely the same response that occurs due to the inhalation of common dust. The OTC Scientific Advisory Committee on Aerosols recommended to the FDA that aerosol antiperspirants be placed in the Review's Category III (more testing needed). Mr. Gilbertson's panel felt that a two-year primate inhalation study was needed to determine the safety of these aerosols. They claimed that monkeys are a better species as a predictor of toxicity in man. With monkeys from India and Bengladesh costing about $1,600 each in late 1980, a 50-plus monkey study, with special housing and feeding costs, could easily run into millions of dollars. Industry was naturally reluctant to fund such a study, if there was any other way to satisfy the agency. While an intense study program was being conducted by the CTFA, the FDA placed aerosol antiperspirants in their Category III (more data needed) classification. As a result of recent clarifications by the courts, FDA has the power to limit this period to a year, which in this instance would have the effect of a delayed ban. After further meetings with industry, in August, 1981, the FDA withdrew the recommendation for a primate study, finding that the data submitted already "provide enough information to satisfy the previous request for subhuman primate data." Instead, they told the cosmetics industry that an aerosolized aluminum chlorhydrate two-year inhalation carcinogenicity study in rats is necessary before it can determine the safety of the antiperspirant ingredient. The industry has agreed tentatively and protocols are under development. Implicit in all of this is that the FDA will maintain aerosol antiperspirant in what amounts to a Category III status, provided the industry moves expeditiously to have the additional testing conducted. Regardless of the results of the study (unless interim results are astonishingly disappointing) the industry will have until about mid-1984 to market aerosol antiperspirants on the present basis. The larger significance of the FDA's actions are not lost on the industry. The agency could be laying the groundwork for more exhaustive testing of other food, drug and cosmetic products that are subject to inhalation by humans, such as hair sprays and after-bath perfumed talc sprays. A hazard in the latter instance is that the present market volume for the talc sprays is in the order of 18 million units per year, hardly sufficient to justify the funding level needed for a multi-million dollar chronic inhalation program. Despite occasional quips that the FDA would prefer to test only heavy-smoking, asthmatic monkeys suffering from pulmonary disfunc-
508 The Aerosol Handbook tion, the whole issue of inhalation testing is one of serious proportions and should not be discounted. It will be with the industry for a long time. Further information on chronic inhalation studies is given in the Toxicology Chapter. Current Good Manufacturing Practice (CGMP), or GMP) regulations are provided in the Code of Federal Regulations, Title 21, Food and Drugs, Parts 200 to 299, U.S. Government Printing Office, Washington, D.C. 4-1-79, pp 61-80. They describe the minimum requirements that a food and drug must satisfy. Increasingly, industry is extending these concepts to the production of cosmetics. In fact, about mid-1977 the industry launched a "Citizen Petition" to have the FDA take action to develop CGMP in the manufacture, processing, packing and holding of cosmetic items, advocating that this language be inserted into the Code of Federal Regulations, Title 21, Cosmetics, Part 750. In 1982, a spokesman for the FDA suggested that the agency might publish cosmetic CGMP as guidelines, and then see if regulations were in fact needed. During 1980, there were about 375 FDA inspections of cosmetic production establishments, and about 89% were found to be deficient in one or more major respects. Raw material and product control practices had the highest deficiency rates: from 46 to 68% deficient. Major problems during the past few years have included recalls of cosmetics with illegal colorants and with microbiological contaminants, including Pseudomonas. Nitro- samine contamination is another area of investigation. Recent studies have shown that the average person absorbs 0.41/ig/day of nitrosamines from cosmetics that pass through the skin and enter the bloodstream, compared with 17.00 /ig/day from one pack of cigarettes. Cured meats are rated below 0.25 ng per serving. The nitrosamine problem with cosmetics may, therefore, be much less critical than it was once thought to be. In the future, contract fillers able to demonstrate a high level of compliance with CGMP will be awarded more business by increasingly quality conscious marketers. After the initial investment is made in bringing the facility into compliance, the tight control of yield accounting, virtual elimination of compounding errors, customer rejections and field recalls, plus a group of other advantages will make the operation more competitive than before. One fairly large cosmetic marketer rates fillers as to plant quality, quality control, quality assurance, warehouse management, production flexibility, predicted relationships and reputation. Many of these attributes have strong CGMP overtones. Plant cleanliness is extremely important, extending even to the immediate grounds. Good lighting, ventilation and screening are required. All reasonable measures must be taken to prevent contamination of chemicals, components and finished product by microorganisms, insects, filth or other extraneous material. Partitions, roped-off areas, separate enclosures or other divisions must be used to prevent cross-contamination, the use of incorrect materials (as from the previous product on a line), or the erroneous shipment of on-hold or quarantined stock into the distribution system. Each chemical and component should be traceable by a trail of paperwork from the time it enters the plant until it leaves, either as finished stock or as rejected material. Yield accounting is important as a means of proving lack of contamination. Every chemical should be analysed upon receipt. Upon approval the initial hold-tag is replaced with one that signifies "Approved For Use" (or a comparable statement) and the lot is transferred to the "Approved Chemicals" area. Batches and finished product are handled similarly. It is impractical to try and provide any more comprehensive treatment of CGMP requirements in these pages, except to restate that a very complete set of records must be kept covering all aspects of the operation. These must include the signed and countersigned results of all analytical and microbiological tests, batch preparations, filling machine operations and other manufacturing records. When an FDA inspector (or a customer's inspection team) audits the facility, from one to three days is required. About 70% or more of that period is spent in answering questions with frequent references to written records. The label of food, drug and cosmetic products must carry the ingredients, listed in descending order of concentration by weight, except that the items present under 1 % may be scrambled if desired. For foods, in many instances standards of identity must be met. For example, if the product is described as honey, that ingredient cannot be legally diluted with water. A limited number of propellents are available for foods, but they include n-butane, isobutane, propane, carbon dioxide, nitrous oxide, nitrogen and Freon FP C318 (perfluorocyclobutane). In the case of drug products, the declaration of ingredients must start with the statement ' 'Active Ingredient'', followed by the one or more items, such as aluminum chlorhydrate, that fit that
Government Regulations 509 description. This is then followed by the statement "Inert Ingredients" or "Inerts", after which the remaining cosmetic type chemicals are listed. In the case of cosmetics, a simple listing is all that is needed. The terminology to be used can be obtained from a book published by the Cosmetics, Toiletries and Fragrances Association (CTFA), which is frequently updated by means of supplements and new editions. The names of chemicals used in the product should conform to the sometimes strange designations in the book, since this provides uniformity and ready reference by poison control centers and other interested persons, (including competitors.) No more material should be used in this declaration than mandated. For example, if SD Alcohol 40 is sufficient, one should not set down SD Alcohol 40-2, since this is both slightly confusing and may limit a firm's options for changing denaturants. New cosmetic ingredients are usually evaluated by the Expert Panel of the Cosmetic Ingredient Review Committee (CIR), with their results published as supplements to the Journal of Environmental Pathology and Toxicology, starting in May, 1980. The panel examines existing cosmetic materials as well, particularly those where scientific reports have indicated a clinical problem area. For example, work in 1980 implicated hydroxyanisole as a potential skin depigmenting agent and this could lead the panel to the conclusion that it is unsafe as a cosmetic ingredient. In another case, the clinical data for cetearyl octanoate was insufficient for the panel to draw any conclusions. In such instances, industry generally has 90 days to inform the panel that such studies will be undertaken and completed within one year. Otherwise delisting follows. Drug and cosmetic items must be labeled in accordance with FDA regulations. The principal display panel must be large enough to accommodate all the mandatory label information without crowding or affecting clarity. The identification of the product must appear, in terms of the common or usual name of the product, as an appropriately descriptive name or as an appropriate illustration, illustrating the intended use. The statement of the identity of the product must be in bold type, of a size reasonably related to the most prominent other printed matter on the panel. The name and place of business of the manufacturer, packer or distributor must also appear on the principal display panel. The net contents declaration must appear on the principal panel, within the bottom 30%, and reasonably separated and distinct from other live matter. However, if the package has a label where the principal display panel is 5 square inches (32.26 cm2), the 30% requirement no longer applies. If the cosmetic or drug is marketed using an outer and inner container, the net weight need not appear on the inner pack. (Most marketers place a net weight declaration on both.) The statement of ingredients also need not appear on the inner pack. For cosmetics packaged in "boudoir type" containers, such as decorative cartridges, pencil shapes and highly stylized glass aerosols, the requirements for the main display panel are modified to permit this data to be inscribed on a removable tag or tape, affixed to the dispenser. In some cases, a small round label is attached to the base of the container, giving the product name, manufacturer's name and address, and generally the net weight. In addition, the manufacturing code is imprinted on this label, or on the container base next to it, if there is room. Aerosol foods, drugs and cosmetics must be labeled according to their deliverable net weight, in accordance with regulations under the Fair Packaging and Labeling Act (FPLA). If the net weight is less than one pound, labeling shall be in terms of ounces, such as "Net Wt 3 oz.". But if the aerosol weight is over one pound (but less than four pounds), the declaration must be given in ounces, but followed in parentheses by a declaration in whole pounds, with any remainder in terms of either ounces or decimal fractions of the pound; for instance, "Net Wt 18!/2 oz. (1 lb 2</2 oz.)" or "Net Wt 20 oz. (1.25 lb)". Supplementary statements may include a declaration in terms of fluid ounces, or one in metric units such as grams, but not on the principal panel and not in any way that might hinder the consumer from making proper value comparisons. For over a decade several products in the institutional hair spray category, packaged in large 211x713 (65 x 198 mm) cans, used the declaration of "Net Contents 20 fl. oz. (1 pint 4 fl. oz.)" as the principal indication of quantity. The "Net Wt 16 oz. (1 lb)" statement was subsidiary. The unspoken rationale for using the volumetric declaration was simply that it provided a larger number, due to the rather low density of the product. At one time during the mid to late 1970s the FDA supported this declaration, based upon a rather old ruling in the area. But after listening to informal petitions for uniformity by the National Bureau of Standards (NBS) and the Interagency Regulatory Liaison Group (IRLG), FDA attorneys finally decided
510 The Aerosol Handbook to support the net weight concept. A still further delay period ensued, since the states are the ones with authority to stipulate fill quantities and provide enforcement actions. Several states, such as Illinois, have suggested no great preference for one mode or the other. In 1982 these particular products have persisted with the volumetric declaration. The size of the net weight declaration is consistant with FPL A standards. The principal label is defined as representing the front 40% of the total labeling area of a container. Where this area is less than 5 sq. in. (32.26 cm2) the label size may be as small as 1/16 " (1.59 mm) in height. Such containers include glass and aluminum aerosols up to about a 2 Av. oz. filling weight. For dispensers with principal panels having an area of between 5 and 25 sq. in. (32.26 to 161.30 cm2) the label size must be at least 1/8" (3.18 mm) in height. This range includes every U.S.A. common aerosol can, except the 300 x 709 (76 x 192 mm) size, which is almost never used for FDA products. According to the FDA, there are about 85,000 establishments in the U.S.A. that are under its regulatory veil. For the 1980-81 fiscal year, FDA was granted a budget of $362.5 million, and in 1978 (the year for which the latest statistics are available) the agency conducted 34,493 establishment inspections, conducted 829 product recalls, 385 surveys, 50 inspection actions and 35 criminal prosecutions. Only about 1.1% of these inspections involved cosmetics plants. Drug-producing plants were visited frequently, and food establishments (including markets, restaurants and grain barges) were visited most of all. The FDA can be expected to become significantly more important to the aerosol industry in the future, as a result of CGMP requirements and their many other activities. Fair Packaging and Labeling Act of 1966 This is a very narrow and specific act, based on the premise that informed consumers are essential to the fair and efficient functioning of a free market economy. Package labeling labels should enable customers to obtain accurate information as to the quantity of the contents and should facilitate value comparisons. The Federal Trade Commission (FTC) has primary jurisdiction over this act, and through issued regulations and interpretations, has established labeling guidelines for consumer products with the exception of foods, drugs, devices and cosmetics. The FDA has concurrent jurisdiction to enforce this act with respect to foods, drugs, devices and cosmetics. The act is straightforward and specific on such factors as type sizes, as indicated in the previous few paragraphs. The act requires the conspicuous statement of the name and place of business of the manufacturer, packager or distributor. Where the product is not manufactured by the company whose name appears on the label, the name must then be qualified by a phrase that reveals the connection such company has to the product. Such phrases as "Manufactured for...", "Distributed by..." or "Sold by..." are used to report the existing relationship. The most appropriate of these is "Distributed by.. .". Various label claims, such as "Cents Off' and "Economy Size" statements, are controlled by the FPLA. Deceptive phrases like "Jumbo", "Giant" and so forth are prohibited. Non-functional oversize packaging, which may give an aerosol product more shelf space and make it look larger to the customer, may be prohibited under the FPLA for cause. Shadow- boxes, for instance, are permitted, since the actual container can be seen. The box provides space for various information of consumer value and makes smaller aerosols less likely to be stolen by shoplifters. Under the act, questionable, suggestive, improprietous or misleading names are prohibited. One of the later provisions of the FPLA is designed to control savings representation abuses, such as certain "cents off' and related promotions. The act requires the retailer to maintain selling price records for a minimum of one year on any item which has been the subject of price or other promotions. Inspectors from the FTC or FDA can then determine if the consumer has, in fact, been given the savings claimed by the store. Packages described as "Economy Size" must show a significant reduction in price per unit of weight; usually at least 5%. A newly developed commodity, or one which has changed in some functionally significant respect, or one that has been newly introduced into a geographic trade area, may be the subject of an "Introductory Offer" type promotion. Such packages may be sold at reduced prices for up to six months, provided they are labeled as "Introductory Offer" merchandise, with the post-promotional price included on the label. The act also concerns itself with several aspects of overpackaging, operating on the concept that excessive or blatantly superior packaging may limit the consumer in making accurate value comparisons. For example,
Government Regulations 511 internal fillers diat are non-functional but serve only to aggrandise package size are prohibited. Any such fillers must be shown to be necessary to protect die fragile inner product. Glass aerosols are sometimes sold in pasteboard boxes lined widi a light corrugate filler, and diis is acceptable to die FDA. One of die more pertinent aspects of die act widi respect to aerosols is die consideration of non-functional slack fill. The most common fill for aerosols is about 85v%, measured at about 70°F (21.1°C). But some packs are below diis level, usually for specific reasons. Many whipped cream products are packed at about 45 v% of can capacity, because diey can carry only a very low percentage of CO2 or N2O before pressures in die can become excessive. The larger head space provides a larger reserve of propellent gas and prevents die foam from becoming soupy near die end of die can. Widi die change-over to hydrocarbon gases as replacements for die chlorofluorocarbon propellents, most problems of non-functional slack fill have been eliminated. Marketers have been concerned about die low densities of hydrocarbon-based products and want to fill cans to die highest practical level to prevent consumer resistance to buying products diat seem to be only half-full or so, on die basis of gross weight. However, there are still infractions of die spirit of die FPLA. One major product used to be formulated widi over 90% chlorofluorocarbon propellent and was packed at die level of 12 Av. oz. (340 g) per 211 x413 (65 x 122 mm) can. Great difficulty was experienced in die transition away from CFCs, about 1978, and die product is now sold as a 4 Av. oz. (113.4 g) fill in die same can size. The can is about 33% full, by volume, at 70°F (21.1°C). Because of die unavoidable concentration of die active ingredient, die product still lasts about as long as die earlier CFC type dispenser. The formulation is more costiy, on a per ounce (or per gram) basis. Because of diese mitigating factors, die company feels its commitment to business ethics has been preserved. In die U.S.A. (unlike Europe) diere has been almost no interest or activity in die fill volume of aerosol products. This includes die non-functional slack-fill area. The Environmental Protection Agency (EPA) The EPA is structurally an independent administrative agency which has charge of several acts and statutes and has a staff which is often augmented by state government parallel agencies such as for die enforcement of clean air standards. During die Carter administration, while die budgets of most regulatory agencies were reduced, die budget for EPA alone was increased by 40% and some 1,300 staff positions were added. In a recent CSMA survey, it was found diat die EPA had by far die greatest effect upon die aerosol industry of any government agency or commission. Now, under die Reagan administration, diere is a hue and cry diat die EPA is about to be destroyed as an effective agency, due to proposed budget reductions. The budgets for fiscal years, including construction grants, amounted to $4.7 billion in 1981 and $5.1 billion in 1982 under Reagan, but were changed to $3.7 billion for 1981 and eidier $3.4 or $3.75 billion for 1982 (not yet setded) under Carter. The request by current EPA Administrator Anne Gorsuch for fiscal 1983 is $3.5 billion. According to Gorsuch, much of die reduction can be justified in terms of eliminating unproductive managers and refocusing enforcement and research toward more productive areas. Persons such as past administrator Russell Train (1973 - 1977) point to die difference of up to $1.7 billion in die 1982 budgets and suggest diat diis represents a 45% cut when inflation is considered, and diat attrition of personnel is currendy running at 32 % per year. It is too early to determine die effect upon industry of diese sweeping changes. However, we do recognize diat even under die halcyon days of Carterism, die EPA inefficiencies, lack of decisionmaking, delays and odier problems were well known to industry. For example, die registration of a routine aerosol pesticide could easily take over two years. The Federal Insecticide, Fungicide and Rodenticide Act of 1947 This act, labeled widi die acronym of FIFRA, was created for purposes of regulating die marketing of economic poisons and devices for using diem. Up to 1970, die act was administered by die U.S. Department of Agriculture (USDA), but dien it was transferred to die newly created Environmental Protection Agency (EPA), where it remains today (1982). Widi regard to aerosol products, die act covers all insecticides, insect repellents, disinfectants, disinfectant cleaners, fungicidal sprays and weed killers. It does not include germicides or fungicides designed to be sprayed on humans or animals. These fall to die FDA. Among die strange products to be included under FIFRA we have a tree-banding spray, which places a barrier of perpetually sticky polybutene/castor wax around a tree so diat various insects cannot crawl up die trunk and eat die leaves or do odier damage. The product was recog- Next Page
Government Regulations Previous Page 511 internal fillers diat are non-functional but serve only to aggrandise package size are prohibited. Any such fillers must be shown to be necessary to protect die fragile inner product. Glass aerosols are sometimes sold in pasteboard boxes lined widi a light corrugate filler, and diis is acceptable to die FDA. One of die more pertinent aspects of die act widi respect to aerosols is die consideration of non-functional slack fill. The most common fill for aerosols is about 85v%, measured at about 70°F (21.1°C). But some packs are below diis level, usually for specific reasons. Many whipped cream products are packed at about 45 v% of can capacity, because diey can carry only a very low percentage of CO2 or N2O before pressures in die can become excessive. The larger head space provides a larger reserve of propellent gas and prevents die foam from becoming soupy near die end of die can. Widi die change-over to hydrocarbon gases as replacements for die chlorofluorocarbon propellents, most problems of non-functional slack fill have been eliminated. Marketers have been concerned about die low densities of hydrocarbon-based products and want to fill cans to die highest practical level to prevent consumer resistance to buying products diat seem to be only half-full or so, on die basis of gross weight. However, there are still infractions of die spirit of die FPLA. One major product used to be formulated widi over 90% chlorofluorocarbon propellent and was packed at die level of 12 Av. oz. (340 g) per 211 x 413 (65 x 122 mm) can. Great difficulty was experienced in die transition away from CFCs, about 1978, and die product is now sold as a 4 Av. oz. (113.4 g) fill in die same can size. The can is about 33% full, by volume, at 70°F (21.1°C). Because of die unavoidable concentration of die active ingredient, die product still lasts about as long as die earlier CFC type dispenser. The formulation is more costiy, on a per ounce (or per gram) basis. Because of diese mitigating factors, die company feels its commitment to business ethics has been preserved. In die U.S.A. (unlike Europe) diere has been almost no interest or activity in die fill volume of aerosol products. This includes die non-functional slack-fill area. The Environmental Protection Agency (EPA) The EPA is structurally an independent administrative agency which has charge of several acts and statutes and has a staff which is often augmented by state government parallel agencies such as for die enforcement of clean air standards. During die Carter administration, while die budgets of most regulatory agencies were reduced, die budget for EPA alone was increased by 40% and some 1,300 staff positions were added. In a recent CSMA survey, it was found diat die EPA had by far die greatest effect upon die aerosol industry of any government agency or commission. Now, under die Reagan administration, diere is a hue and cry diat die EPA is about to be destroyed as an effective agency, due to proposed budget reductions. The budgets for fiscal years, including construction grants, amounted to $4.7 billion in 1981 and $5.1 billion in 1982 under Reagan, but were changed to $3.7 billion for 1981 and eidier $3.4 or $3.75 billion for 1982 (not yet setded) under Carter. The request by current EPA Administrator Anne Gorsuch for fiscal 1983 is $3.5 billion. According to Gorsuch, much of die reduction can be justified in terms of eliminating unproductive managers and refocusing enforcement and research toward more productive areas. Persons such as past administrator Russell Train (1973 - 1977) point to die difference of up to $1.7 billion in die 1982 budgets and suggest diat diis represents a 45% cut when inflation is considered, and diat attrition of personnel is currendy running at 32 % per year. It is too early to determine die effect upon industry of diese sweeping changes. However, we do recognize diat even under die halcyon days of Carterism, die EPA inefficiencies, lack of decisionmaking, delays and odier problems were well known to industry. For example, die registration of a routine aerosol pesticide could easily take over two years. The Federal Insecticide, Fungicide and Rodenticide Act of 1947 This act, labeled widi die acronym of FIFRA, was created for purposes of regulating die marketing of economic poisons and devices for using diem. Up to 1970, die act was administered by die U.S. Department of Agriculture (USDA), but dien it was transferred to die newly created Environmental Protection Agency (EPA), where it remains today (1982). Widi regard to aerosol products, die act covers all insecticides, insect repellents, disinfectants, disinfectant cleaners, fungicidal sprays and weed killers. It does not include germicides or fungicides designed to be sprayed on humans or animals. These fall to die FDA. Among die strange products to be included under FIFRA we have a tree-banding spray, which places a barrier of perpetually sticky polybutene/castor wax around a tree so diat various insects cannot crawl up die trunk and eat die leaves or do odier damage. The product was recog-
512 The Aerosol Handbook nized by the EPA as an insect repellent after it had been on the market almost twenty years. In a similar case, a product consisting of methyl Cellosolve, propelled with nitrogen gas, was used as an additive to jet fuel. In the fuel tank it acted to dissolve possible small pools of condensed water, which (rather surprisingly) could support several species of microorganisms. If a sufficient amount of these bacteria entered the delicate jet engine of certain private aircraft, a burn-out might occur. By solubilizing the water, the bacteria could no longer grow. The EPA determined that the product should be considered as a bactericide, based upon label claims. Approximately 12% of all aerosol products "belong" to the EPA. All economic poisons must be EPA-registered before interstate shipment can occur. Sales in most states are prohibited without federal registration. States that require in-state registration rarely impose any further testing or informational requirements on EPA-registered products. A notable exception is California, which is discussed later in this chapter. Like a New Drug Application (NDA), the registration of a new toxicant substance under FIFRA can easily cost in excess of a million dollars and take several years of intense effort. Only the largest raw material firms can afford such programs. Some of the more recent pesticides include hormones that arrest the developmental stages of an insect, pheromone sex attractants and bio-rational organisms. Economic poisons can be added to aerosol formulations without restraint, provided the product label does not make pesticidal claims or indicate the inclusion of these substances, which the EPA considers an implication to the customer that the product is an economic poison. Disinfectant chemicals are often included in air deodorizers, and in various products for their preservative action. These products need not be EPA-registered. In a broad sense, label claims (not composition) are what constitute classification of products as an economic poison, a drug, a germicide or even a food. However, in some instances labeling must relate to composition, especially for products controlled by the Consumer Product Safety Commission (CPSC) which contain certain hazardous substances. The labeling requirements for pesticides are complex, and are covered in the Code of Federal Regulations Title 40, Part 162.10. The name, brand or trademark of the pesticide must appear on the front panel. It must have been approved during registration and not be false or misleading. The name of the producer, registrant or person for whom produced must appear on the label, along with the appropriate address. If the product was produced by one firm and marketed by another whose name then appears on the label, qualifying words must be added, as "Distributed by. . . " or "Sold by. . . ". An unqualified name and address on the label shall be considered by EPA to be the name and address of the producer. For aerosol pesticides the measure of the contents shall be in terms of weight, expressed as Avoirdupois pounds and ounces. In all cases the largest suitable units shall be used: i.e., "Net Wt 1 lb. 1 oz." instead of "17 Av. oz.". In addition to the net weight in the Avoirdupois system, it may be expressed in metric units (grams). The variation above a minimum content or around an average is permissible only to the extent that it represents an unavoidable deviation still consistant with good manufacturing practice. In no case shall the average content of the packages in a shipment fall below the stated average content. The product registration number must appear on the label in formats such as "EPA Registration Number 11525-89" or "EPA Reg. No. 11525-90" in a type size not less than 6 points high (2.12 mm) and in any case not smaller than nearby type sizes. The producing establishments registration number must also appear, using a format such as EPA Est. 11525-IL-2", either on the label or on the immediate container—sometimes as a bottom code, together with any manufacturing codes. In the example, 11525 is the establishment identification number, the IL stands for Illinois, and the 2 signifies that the producing plant was the second one in Illinois to be registered and used by the producer. Label type size must be at least 6 point (2.12 mm) The ingredient statement must appear on the front panel of the label in easily read type of not less than 6 point (2.12 mm) size. After the phrase "Active Ingredients):" name and the total percentage by weight of each active ingredient must be listed. If there are inert ingredients, then the phrase "Inert Ingredient(s):" must be placed directly below the phrase ' 'Active Ingredients):" and followed by the total percentage of all such ingredients. The EPA may require the listing of any particular inert ingredient (such as sodium nitrite), if they consider that it may pose a hazard to man or the environment. Required warnings and precautionary statements concerning general areas of toxicological hazard fall
Government Regulations 513 Table I EPA Product Toxicity Categories For Labeling Purposes Hazard indicators . Toxicity Categories I II III IV Oral LD50 Up to and including 50 mg/kg Inhalation LC50 Up to and including .2 mg/liter. Dermal LD50 Up to and including 200 mg/kg. Eye effects Corrosive; corneal opacity not reversibli within 7 days. Skin effects Corrosive From 50 thru 500 mg/kg From .2 thru 2 mg/ liter. From 200 thru 2000 Corneal opacity re- : versible with 7 days; irritation persisting for 7 days. Severe irritation at 72 hours. From 500 thru 5000 mg/kg From 2. thru 20 mg/ liter. From 2,000 thru 20,000. No corneal opacity; irritation reversible within 7 days. Moderate irritation at 72 hours. Greater than 5000 mg/kg Greater than 20 mg/ liter. Greater than 20,000. No irritation. Mild or slight irritation at 72 hours. into two groupings: those required on the front panel, and those which may be placed anywhere. As indicated in the chapter on Aerosol Toxicology, there are four toxicity categories in use by the EPA, labeled I, II, III and IV. The category assigned to an economic poison is the highest of the results of any of the five clinical tests: oral LD50, inhalation LC50, dermal LD50, eye effects and skin effects. These limits are explained in Table I. According to the toxicity category of the product, the following signal words must appear on the front panel: Category I "POISON", Category II "WARNING", Category III "CAUTION" and Category IV "CAUTION". For Category I, in some cases, and for the other categories in all instances, the signal word may be followed by a statement such as "See practical Table II Type Size of Warning and Precautionary Statements for the Label of EPA Products Size of Product Label (in2) Total Front Panel Required Keep Out Precau- Signal of Reach of tionary Word* Children Statement Points Points Points Up to 12.5 Above 12.5-25 Above 25-37.5 Above 37.5-75 Above 75 Up to 5 Above 5-10 Above 10-15 Above 15-30 Above 30 6 10 12 14 18 6 6 8 10 12 *A11 capitals. For metric conversion, 1 point is 0.353 mm. The 300 x 709 (76 x 192 mm) can has a total label size of about 69 in2 (444 cm2). Table III Typical EPA Precautionary Statements by Toxicity Category Toxicity Category Oral, Inhalation, or Dermal Toxicity Skin and Eye Local Effects. II III IV Fatal (poisonous) if swallowed [inhaled or absorbed through skin]. Do not breathe vapor [dust or spray mist]. Do not get in eyes, on skin, or on clothing. [Front panel statement of practical treatment required.] May be fatal ifswallowed [inhaled or absorbed through the skin]. Do not breathe vapors [dust or spray mist]. Do not get in eyes, on skin, or on clothing. [Appropriate first aid statement required.] Harmful if swallowed [inhaled or absorbed through the skin]. Avoid breathing vapors [dust or spray mist]. Avoid contact with skin [eyes or clothing]. [Appropriate first aid statement required.] [No precautionary statements required.] Corrosive, causes eye and skin damage [or skin irritation]. Do not get in eyes, on skin, or on clothing. Wear goggles or face shield and rubber gloves when handling. Harmful or fatal in swallowed. [Appropriate first aid statement required.] Causes eye [and skin] irritation. Do not get in eyes, on skin, or on clothing. Harmful if swallowed. [Appropriate first aid statement required.] Avoid contact with skin, eyes or clothing. In case of contact immediately flush eyes or skin with plenty of water. Get medical attention if irritation persists. [No precautionary statements required.)
The Aerosol Handbook Table IV Form Approved OMB No. 158-R0066 U.S. ENVIRONMENTAL PROTECTION OFFICE OF PESTICIDES PROGRAM (WH-567) WASHINGTON. D.C. 20460 APPLICATION FOR NEW PESTICIDE PRODUCT REGISTRATION (Please read instructions on reverse before completing) A 1. REFERENCE CODE 3. COMPANY/PRODUCT NO. 5. NAME AND ADDRESS OF APPLICANT (Include ZIP Code) r -i L- _l I | CHECK IF THIS IS A NEW ADDRESS 8. PRODUCT NAME 10. LOCATION OF LABEL DIRECTIONS I 1 ON LABEL Q3 ON MATERIAL ACCOMPANYING PRODUCT 2. ...;.. .::MP*:m£'OHt^<'r(mA '&&>}4&X?-.^3ikl 4. PROPOSED CLASSIFICATION I | GENERAL I | RESTRICTED 8. TYPE OF CONTAINER I |METAL 1 1 PLASTIC 1 1 GLASS 1 1 PAP ER 1 1 OTH ER (Specify) 7. WILL CHILD RESISTANT PACKAGING BE USED? □ YES 1 1 NO 9. EXPERIMENTAL PERMIT NO. 11. MANNER IN WHICH LABEL IS AFFIXED TO PRODUCT □ LITHOGRAPH 1 | OTHER (Specily) I | P APER GLUED f_ ] STEN CIL ED 12. TYPES OF DATA SUBMITTED 01. NONE 02. PRODUCT CHEMISTRY 03. RESIDUE CHEMISTRY 04. ENVIRONMENTAL CHEMISTRY 0 5. EFFICACY 06. PH Y TO TO XI CI TY 07. HUMAN SAFETY 08. DOMESTIC ANIMAL SAFETY 09. FISH AND WILDLIFE SAFETY 10. BENEFICIAL INSECT SAFETY 11. ACCIDENT EXPOSURE EXPERIENCE 12. OTHER (Speciiy) 13. OTHER (Specify) 13. METHOD OF SUPPORT (See instructions) 1 1 Required Supporting Data Attached. (2 A) 1 1 Required Supporting Data is Submitted ' ' by Reference. (2B) 1 . Proceed on the Basis of Established Use 1—! Patterns. (2C) OFFER TO PAY STATEMENT 1 hereby offer to pay reasonable compensation to the extent provided under Section 3 (c)(1)(D) of the Federal Insecticide, Fungicide, and Rodenticide Act, as amended, and in accordance with the Regulations and Guidelines published thereunder for use of any test data which has been submitted to the U.S. Environmental Protection Agency in connection with an application for the registration of a pesticide for the first time on or after October 21, 1972 and which maybe used in support of the registration application for the subject pesticide. 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 121 1 1212 1213 14. CONTACT POINT Complele items directly below for identification of individual to be contacted, if necessary, to process this application. NAME TITLE TELEPHONE NO. (Include Area Code) 16. SIGNATURE 18. TYPED NAME 17. TITLE 19. DATE SIGNED FOR EPA USE ONLY -':''.'::-:.:;: : ■ ; 15. DATE APPLICATION RECEIVED (Stamped) EPA Form 8570-1 (Rev. 11-74) previous editions are obsolete.
Government Regulations 515 treatments on back panel" or " See back panel.'' But in all cases, the words "Keep out of reach of children" must appear on the front panel. All the precautionary information provided on front and back panels must be kept together and reasonably segregated from other printing matter. The front panel is 40% of the total label size. Type sizes are stipulated for the precautionary statements and must conform to the information in Table II. Typical precautionary statements are illustrated in Table III. In the special case of aerosol products where they are found to be "Flammable" or "Extremely Flammable", the test results and required statements are given in the Aerosol Flammability chapter. The actual process of obtaining an EPA registration is rather painstaking and certainly quite time consuming, as viewed by contract fillers and marketers. It can become frustrating and expensive if unforseen delays come up. As a rule, the process begins with the utilization of a prototype formulation suggested by and registered to one of several large pesticide compounders and resellers. The McLaughlin Gormley King Co., the S.B. Penick Unit (CPC International Inc.) and the Fairfield American Corp. are three such firms. Full supporting data will have been filed with the EPA in the process of registering these formulations, and this must be referenced in filings by fillers and marketers. Alternately, a "me-too" conditional registration may be sought where the proposed product is identical to or substantially similar to a product already registered. New users need an incremental risk assessment before a decision can be made to provide conditional registration. In the case of disinfectant/deodorants and disinfectant cleaners, the filler or marketer can develop reasonable formulations based upon disinfectant chemicals or mixtures already registered with the agency. These are then tested for efficacy against one or more bacteria by the Official AOAC Germicidal Spray Test and, depending upon desired product claims, on specific organisms, such as Pseudomonas aerogenes, Mycobacterium tuberculosis, Influenza A (virus), Trichophyton mentagrophytes (fungus) and so forth. A routine industrial microbiological laboratory can handle all the tests except the virus and tuberculosis organisms. For these, a more elaborate laboratory facility is needed, since the procedures are more complex and the safety of the operator is more at risk. Special testing is required for special products. For instance, indoor foggers are designed to control large areas and even small houses with one total-can discharge. Except for the "me-too" conditionals, testing for these formulas cannot be fully satisfied by Peet- Grady tests and others of small scale proportions. In one case, an entire house was constructed near Baltimore, MD and deliberately infested within walls and in all areas. It was then treated. Afterward the house was literally taken partially apart to determine the effectiveness of the product. Insect repellent formulations likewise require special testing. The proposed product must also be tested for possible flammability, and for clinical toxicity (see Table I). According to the results of the toxicity data (for insecticides) or efficacy data (for disinfectants), plus the flammability and toxicological data, a label is then developed. The label should contain all the claims for the finished product, but these should not exceed those established experimentally during the testing program. The applicant is then ready to file an application for the registration of an economic poison. The minimum requirements for a submission to the EPA are listed as follows: a. Application for New Pesticide Product Registration (EPA Form 8570-1 (Rev. 11-74)). Note 1. b. Confidential Statement of Formula (EPA Form 8570-4 (Rev. 12-74)). Note 2. c. Proposed labeling, including all printed or graphic matter which may accompany the sale of the product. Note 3. d. Biological efficacy data. Note 4. e. Mammalian toxicological data. Note 5. f. Cite all certification. Note 6. g. Generic Data Summary Sheet (FIFRA pph. 3(C)(2)(B)). Note 7. h. Child-resistant closure data. Note 8. Note 1. A copy of this form is shown as Table IV. Note 2. A copy of this form is shown as Table V. If the formula or any of its ingredients are unknown to the applicant, then the "basic supplier" must supply this information, often by giving the EPA written permission to utilize certain confidential records maintained at the Pesticides Office for that purpose. An example of unknown ingredients are the inhibitors and emulsifiers used for water-based insecticides.
516 The Aerosol Handbook Table V Form Approved OMBNo. 158 • R0066 U.S. ENVIRONMENTAL PROTECTION AGENCY OFFICE OF PESTICIDE PROGRAMS (WH-S67) WASHINGTON. D.C. 20480 CONFIDENTIAL STATEMENT OF FORMULA (See instructions on back of last page) C 3. NAME AND ADDRESS OF APPLICANT/REGISTRANT (Include Zip Code) 7. NAME AND ADDRESS OF PRODUCER (Include Zip Code) U. PRODUCT NAME "F1 t * IH lis?-: m |-i||:--! ;;;i * p l"». COMMERCIAL COMPONENT (List each as actually introduced into this formulation. Give 1' rade Name (if any). Name o/ Supplier, and EPA Registration Number ii applicable) f liquid measure, give specific gravity or ounds per gallon. 21. SIGNATURE AND TITLE 1. PAGE OF 2. REGISTRATION/FILE SYMBOL 4. CONTAINER SIZEISI 6. COUNTRY WHERE FORMULATED 8. WEIGHT/GALLON DENSITY 11. pH 9. WEIGHT/UNIT TABLET 12. PERCENT FREE ALKALI 15. FLASH POINT/FLAME EXT ,8- AMOUNT OF EACH COMPONENT' TOTAL WEIGHT OF BATCH 19. PERCENT BY WEIGHT 100.00% 22. NAME OF FIRM 5» LOCATION OF NET CONTENTS 1 1 CONTAINER □LABEL 10. SOLUBILITY RATE 13. DRUM TEST 16. DIELECTRICAL BREAKDOWN VOLTAGE 20. PURPOSE IN FORMULATION 23. DATE SIGNED EPA Form 8570-4 (R*v. 12-74) PREVIOUS EDITIONS ARE OBSOLETE.
Government Regulations Table VI 517 It- U.S. Government Printing Office: 1975-627-714 Form Approved OMB No. 1S8-R0066 U.S. ENVIRONMENTAL PROTECTION AGENCY OFFICE OF PESTICIDE PROGRAMS (WH-567) WASHINGTON. O.C. 20460 LABEL TECHNICAL DATA (Sea INSTRUCTIONS on back of last part) 4. APPLICATION SITES (Check all that apply) 01 CROPS (Fruit) 02 CROPS (Vegetable) 03 CROPS (Field) 04 CROPS (Spice) 05 CROPS (Nut) 09 CROPS (Other) 10 SOI LTREA TMEN T (No crop specified) 20 FOREST 30 ORNAMENTALS 40 TURF 50 STOREO PRODUCTS TREATMENT 01 ANIMALS (Livestock) 62 ANIMALS (Dairy) 63 ANIMALS (Pet) 64 animals (Laboratory) 69 ANIMALS (Other) 71 OUTDOOR (Nocrop Agricultural) 72 OUTDOOR (Rasident/Commercial) 73 OUTDOOR (Non agricultural) 61 BUILDINGS (Agricultural) 82 BUILDINGS fCommerc/a/J S3 BUILDINGS (Food Processing) 84 BUILDINGS (Medical) 85 BUILDINGS (Residential) 91 EQUIPMENT (Commercial) 92 EQUIPMENT (Food) 93 EQUIPMENT (Agricultural) 94 EQUIPMENT (Medical) 95 EQUIPMENT (Transporta//onJ 96 LAUNDRY AND DRY CLEANING 97 INDUSTRIAL PRESERVATIVES 96 PESTICIDE (Manufacturing only) 99 OTHER (Speclly) 1. COMPANY/REGISTRATION NO. 2. EPA USE 0NLT 3. PRODUCT NAME 5. PEST TYPE (Check ail that apply) 01 ALGAE 02 AMPHIBIAN/REPTILE 03 BACTERIA 04 BIRDS 05 FISH 06 FOULING ORGANISMS 07 FUNGI 08 INSECTS AND MITES 09 MAMMALS in NEMATODES 11 PLANTS 12 RODENTS 13 SLIME 14 SLUGS ANO SNAILS 15 VIRUS 16 OTHER (Specily) 6. MODE OF ACTION (Check all that apply) 01 ATTRACTANT 02 BIOLOGICAL CONTROL 03 CHEMOSTERILANT 04 DEFOLIANT OS DESICCANT 05 FEEDING DEPRESSANT 07 GROWTH INHIBITOR 06 GROWTH REGULATOR 09 POISON (Single dose) 10 POISON (Multiple Dose) 1 f PRESERVATIVE 12 REPELLENT 1 3 OTHER (Specify) 7. USER TYPE (Check alt that apply) 01 UNSPECIFIED GENERAL USE 02 UNSPECIFIED RESTRICTED USE 03 HOMEOWNEft USE 04 JANITORIAL USE 05 PEST CONTROL OPERATOR USE 06 COMMERCIAL APPLICATOR USE 07 FARMER USE 08 MEDICAL USE 09 VETERINARY USE 10 GOVERNMENT AGENCY USE 11 MANUFACTURING USE 8. FORMULATION (Check one only) 01 TECHNICAL CHEMICAL 02 FORMULATION INTERMEDIATE 03 OUST 04 GRANULAR 05 PELLETED/TABLETTED 06 WETTABLE POWDER 07 WETTABLE POWDER/OUST 08 CRYSTALLINE 09 MICROENCAPSULATED 10 IMPREGNATED MATERIALS 11 SELF-GENERATING SMOKE 12 EMULSIFIABLE CONCENTRATE 13 INVERT EMULSION 14 FLOWABLE CONCENTRATE 15 SOLUBLE CONCENTRATE 16 SOLUTION (Ready to Use) 17 OILS (No added pesticide) 18 PRESSURIZED (Gas) 19 PRESSURIZED (Liquid) 20 PRESSURIZED (Dust) 21 OTHER (Speclly) REMARKS EPA Form 8570-10 (11-74)
518 The Aerosol Handbook Table VII REVISED 8/10/79 CERTIFICATION STATEMENT EPA File Symbol/ Reg. No. Date of application to which this statement applies Product Name Applicant's Name and Address I certify that I have notified in writing the companies (except those with whom I have reached written agreement) who have submitted data upon which I have relied to support my application and offered to: 1. Pay compensation for those data in accordance with Sections 3(c)(1)(D) and 3(c)(2)(D) of the Federal Insecticide, Fungicide and Rodenticide Act, as amended; and 2. Commence negotiations to determine which data are subject to the compensation requirements of FIFRA, and the amount and terms of compensation, if any, due. The companies I have notified are: f~f All companies listed on the Pesticide Data Submitters List for all active ingredients contained in my product (see 40 CFR 162.9-5). (Check this box only if you are using the "cite-all" method of support.) n All companies listed on the Pesticide Data Submitters List for all active ingredients contained in my product which are not derived from registered and purchased products (see 40 CFR 162.9-8(f)). (Check this box only if you are using the "combined" method of support.) n Those companies who have conducted the studies which I have submitted (or cited if conducted with an identical product)(see 40 CFR 162.9-8(e)). (Check this box if you are using either the "alternate" method of support or the "combined" method of support.) Signature and Title Typed name Date signed
Government Regulations 519 Table VIII FIFRA S 3(C)(2)(B) SUMMARY SHEET Appendix III-2 EPA Registration No. Product Name: Applicant's Name: Registration Standard for Products Containing; Date Registration Standard Issued: Date Guidance Package Issued: With respect to the requirement to submit "generic" data imposed by the FIFRA section 3(c)(2)(B) notice contained in the referenced Guidance Package, I am responding in the following manner: 1. 2. 5. 6. Attached is a completed "Generic Data Exemption Statement.' I will submit data in a timely manner to satisfy the following requirements. If the test procedures I will use deviate from (or are not specified in) the Registration Guidelines or the Protocols contained in the Reports of Expert Groups to the Chemicals Group, OECO Chemicals Testing Programme, I enclose the protocols that I will use: I have entered into an agreement with one o- more other registrants under FIFRA S 3(C)(2)(B)(ii) to satisfy the following data requirements. The tests, and any required protocols, will be submitted to EPA by (name of other registrant). I enclose a completed "Statement of Willingness To Enter Into An Agreement With Other Registrants For Development Of Data" with respect to the following data requirements: I request that you amend my registration by deleting the following uses: I request voluntary cancellation of the registration of this product. Dated: Registrant's Authorized Representative: (signature) (typed)
520 The Aerosol Handbook Table IX GENERIC DATA EXEMPTION STATEMENT Appendix III-l EPA Product Registration Number:, Registrant's Name: _________ As an authorized representative of the registrant of the proauct identified above, I hereby certify that: (1) I have read and am familiar with the terms of a Notice in a Guidance Package from EPA dated concerning a requirement for submission of generic data on the active ingredient _____________________________ under FIFRA Section 3(c)(2)(B). (2) My firm requests that EPA not suspend the registration of our product, despite our lack of intent to submit the data in question, on the grounds that the product is an end-use product and it contains the active ingredient solely as the result of the incorporation into the product {during formulation or packaging) of a manufacturing-use product which contains that active ingredient, which is registered under FIFRA Section 3, and which is purchased by us from another producer. (3) An accurate confidential formula statement for the above-identified product, is attached to this statement. That formula statement indicates, by company name, registration number, and product name, the source of the active ingredient in my firms's product. My firm will apply for an amendment to the registration prior to changing the source of the active ingredient in our product. (4) I understand, and agree on behalf of my firm, that if at any time any portion of this Statement is no longer true, or if my firm fails to comply with the undertaking made in this statement, my firm's product's registration may be suspended in accordance with FIFRA Section 3(c) (2)(B). Dated: Registrant's Authorized Representative: (Signature) (Typed)
Government Regulations 521 Note 3. Requirements include submission of Label Technical Data (EPA Form 8570-10 (Rev. 11-74)), as shown in Table VI. Copies of the container label, any hang-tags, any outer-pack or shadow-box labeling and so forth must also be submitted. A typewriter may be used to prepare the copy at this stage. Note 4. Such data include: i. Knockdown and kill data for insecticides ii. Microbiological efficacy for disinfectant/ deodorants iii. Microbiological efficacy, removal of 5% blood serum stains, efficacy in hard water. Refer to the EPA's Label Requirement listings DIS/TSS-1 (April 24, '81), DIS-TSS-2 (Jan. 25, '79 and DIS/TSS-15 (March 24, '81) iv. Insect repellency data for insect repellents. Note 5. Minimum tests include oral LD5o, inhalation LC5o, dermal LD5o, eye effects and skin effects, as described in Table I. Note 6. A copy of the cite-all Certification Statement is shown in Table VII. Note 7. A copy of the FIFRA pph. 3(CX2XB) Summary Sheet pertaining to the requirement to submit "generic" data is illustrated in Table VIII. Most applicants elect to check box number one of this form, in which case a "Generic Data Exemption Statement" must be completed. This statement is illustrated in Table IX. Note 8. Certain pesticides may require child-resistant closures, as defined in Title 40 Code of Federal Regulations, Chapter 1, Sub-chapter E, pph. 162.16(c)(2). An example is a disinfectant toilet bowl cleaner. If this is the case, the EPA requires an exact description of the proposed child-resistant closure so they can refer to test data, filed with the agency by the closure supplier, for review purposes. If such data is not filed, the applicant must have the closure tested or arrange with the "basic supplier" to get this work done and have it submitted. According to circumstances, additional information may be required. For example, a disinfectant cleaner using detergents unknown to the EPA may be subject to testing for possible chronic skin sensitization, which costs somewhat over $2,000 and requires several months for test results to become available, since studies involve first hamsters and then (if there are no problems) human subjects. Unknown chemicals are approved without difficulty if they are classed as perfume ingredients. When filing an application, great care should be exercised in developing a correct label. A good label can reduce the waiting time considerably. The EPA has tabulated labeling requirements into a handy reference guide, shown here as Table X. In a typical instance, an application may be made on Jan. 1, 1982; by Feb. 15, 1982 the firm may receive an acknowledgement from the EPA saying that it has been received and is being processed. On May 1, 1982 a "First Action" will be received. The EPA will write the applicant a letter, usually listing from 3 to 40 specific points of objection, often concerning the label. As the skill of the applicant increases in drawing up proposed labels and applications in general, the number of objections will decrease markedly. The objections may be classified as: a. Label changes must be made, as stipulated. b. Further descriptive or clarification data is needed, needed. c. Additional test data is required. (Sometimes this can be handled by changing or deleting label claims.) The applicant is now given six months in which to respond. Otherwise the application is simply discarded. In many cases, the'' First Action" results in a finding that the product is acceptable for registration "as-is", or with the stipulation that certain minor label changes must be made. An EPA Registration Number is provided, since it will have to appear on the finished label. The firm now finalizes the format of their label and arranges for printing, making sure that type sizes, proximity limits and other requirements are met. A print- shop is then engaged to prepare a small number of final labels, five of which are submitted to the EPA with a covering letter. Typically, this takes a month, and brings the data forward to June 1, 1982. After another ten weeks or so, the agency provides the applicant with an official "Notice of Registration" and a stamped and initialed approved copy of their label, for reference purposes. This brings the registration process to August 15, 1982, or to a total elapsed time of 7J4 months. During 1981 and 1982, this minimum time was virtually unimprovable. A more average time was 9 months, partly because of the time needed to prepare the final label, which might also take the form of "black-and-white" lithographic proofs, screen printed papers made by taping a piece of paper to the container as it goes through the printing process, photo-reduced copies of accompanying advertising matter. In several instances, where a novice registrant
522 The Aerosol Handbook Table X Labeling Requirements of the FIFRA, As Amended (Refer to the sample labels on page 524 following Part II of this table) Item 1 2 3 4 5 6a 6b 7 7a 7b 7c Label Element Product Name Company Name and Address Net Contents EPA Reg. No. EPA Est. No. Ingredients Statement Pounds/Gallon Statement FRONT PANEL PRECAUTIONARY STATEMENTS Keep Out of Reach of Children (Child Hazard Warning) Signal Word Applicability of Requirement All Products All Products All Products All Products All Products All Products Liquid products where dosage given as lbs ai/unit area All Products All Products All Products Skull & Cross Bones and All products which are word "POISON" (in Category I based on red) oral, dermal or inhalation toxicity Placement on Label Required Preferred Front Panel None None None None Front Panel Front Panel Front Panel Front Panel Front Panel Front Panel Center front panel Bottom front panel or end of label text Bottom front panel or end of label text Front Panel Front panel, immediately before or following Reg. No. Immediately following product name Directly below the main ingredients statement Above signal word Immediately below Child Hazard Warning Both in close proximity to signal word Comments If registrant is not the producer, must be qualified by "Packed for**" "Distributed by***", etc. May be in metric units in addition to U.S. units Must be in similar type size and run parallel to other type May appear on the container instead of the label Text must run parallel with other text on the panel All front panel precautionary statements must be grouped together; preferably blocked Note type size requirements Note type size requirements All products in Category I: Front Front panel for all Categories I, II, and III panel unless referral statement is used. Others: Grouped with side panel precautionary statements 7e 8 8a Referral Statement SIDE/BACK PANEL PRECAUTIONARY STATEMENTS Hazards to Humans and Domestic Animals All products where precautionary labeling appears on other than front panel All Products All Products in Categories I, II, and III Front Panel None None Top or side of back panel preceding Directions for Use Same as above Must be grouped under the headings given in 8a, 8b, and 8c; Preferably blocked Must be preceded by appropriate signal word 8b Environmental Hazards All Products None Same as above Environmental hazards include the bee caution where applicable 7d Statement of Practical Treatment
Government Regulations 523 is involved, or when a relatively complex or' 'different'' product is to be registered, the process can take two years and longer. In 1971, a typical registration was less complicated, but still took an average of a year. At times during the 1970s, when the agency had special problems, such as the five-year review of registrations and the suit involving the agency's use of supposedly confidential supplier data in the registration of other people's products, product registrations took an average of three years. Currently, the time is about 9 months, but it could well lengthen if planned budgetary cuts limit the staff in the Pesticides Regulation Division of EPA. Long registrations have their problems. Overly long waiting times, not anticipated in PERT diagrams, have often held up these complex timetables for product introductions, "deals", improvements, advertising campaigns and the like, at great expense to the marketer. Occasionally the laws or regulations will change interimly, so that materials initially found to be acceptable may have to be revised. There are numerous products now on the market which the EPA would not register today, without new information, different labels or other caveats. In some instances, tests have been required that were so costly as to be beyond the reach of the marketer or filler, and the project was dropped. As an example of this, a complex organic chemical was found to have the property of dramatically slowing down the growth rate of lawn grass (and other grasses). Depending upon dosages, lawns could be mowed only once a month, or even less frequently. When registration was sought, the EPA's response indicated an expense level about on a par with the net worth of the would-be marketer, and the project was dropped. Once a "Notice of Registration" is secured, the applicant may proceed with production and interstate sale of the product. No change in formula, labeling, or even the size of the product can be made without EPA review and approval. This is handled by submitting an "Application for Amended Registration of Economic Poisons''; PR Form 9-198. No person other than applicant may distribute the product under a different name unless an "Application for Supplemental Registration for Distributors"; Form 9-1, is submitted. Intrastate distribution and sales are not covered by the EPA unless interstate commerce is "affected", but all the States have their own apparatus for dealing with economic poisons, usually still under their Department of Agriculture, so that it is fair to say that all shipments of economic poisons are covered under existing law. During 1970 the USDA stipulated that all economic poison labels must be resubmitted every five years. They would then be evaluated for continued compliance with newer laws, regulatory interpretations and testing procedures. This requirement covered over 65,000 labels at the time, and presented the EPA with an essentially impossible task. In attempts to comply with the wish of Congress many other programs were unattended. The situation was finally resolved, and it is reasonably safe to suggest that such massive reviews will not be conducted (or attempted) in future years. In the enforcement of the law (FIFRA), samples collected from interstate shipments by official inspectors are tested analytically and microbiologically. The analytical methods are generally reserved for insecticides and herbicides. The label is checked for compliance with that shown for the product registration. If a disparity is detected, the EPA's Pesticides Enforcement Branch sends a certified letter to the manufacturer (not the distributor, necessarily) and demands an explanation and statement of intentions. The manufacturer has twenty days in which to respond, showing cause and the steps that will be taken to regain compliance. Mild infractions are usually permitted to remain in sales channels, but severe violations can result in seizures, court actions <and heavy fines. Contract fillers have become aware that they are liable, under the law, for compliance of products they produce for marketing firms. In many instances, contract fillers are unaware of the formula, nor do they have the analytical or microbiological facilities to check compliance. In their review of economic poison labels, the EPA takes special notice of those words and phrases which describe the product or its potency. They disallow any claims which state or imply efficacy beyond the proven capabilities of the product. Some typical descriptive words are defined as follows: a. Insecticide. Any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any insects which may be present in any environment. b. Fungicide. Any substance or mixture of substances intended for preventing, destroying, repelling or mitigating any fungi. c. Rodenticide. Any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating
524 The Aerosol Handbook Table X - Continued Item Label Element Applicability of Requirement Placement on Label Required Preferred Comments 8c Physical or Chemical Hazards All pressurized products; others with flash points under 150°F None Same as above 9a Restricted Block All RESTRICTED products Top center of Preferably blocked front panel Includes a statement of the terms of restriction. The words "RESTRICTED USE PESTICIDE" must be the same type size as signal word. 9b Statement of Classifica- All products classified tion GENERAL Immediately following heading of Directions for Use 9c Misuse Statement All products Immediately following Statement of Classification or head of Directions for Use 10a Re-entry Statement All cholinesterase In the Directions inhibitors for Use Immediately after Misuse Statement 10b Category of Applicator All RESTRICTED In the Directions products for Use Immediately after Reentry Statement (when used) 10c Storage and Disposal All products Block In the Directions for Use Immediately before specific directions for use or at the end of directions for use Must be grouped together, and preferably blocked. Heading must be same type size as Child Hazard Warning lOd Directions for Use All products None None May be in metric units as well as U.S. units. © ® © ■^r SIOltAGC ANO OtSI'OSAL <SL> '-? ====== PRODUCT NAME © ■© <© KEEP OU! OF flEACH OF CHILDREN CAUTION ©►•;■ a 'Mi 'on unfix* nt(tuiOHi>*> utimitii \ (\^\ •.'-.r-z-ri^ ©i © ©> mcujtuuAi ■■*■<•*•■■• ®y~~?--~ *■ tHIHI tt*ltu«Hl STOnAQE ANO INSPOSAL RESTRICTED USE PESTICIDE PRODUCT NAME ■ © ® © ..... KEEP OUl Of REACH OF CHIlOnEN ©♦ DANGER-POISON —, IOHH •)«« = <© ♦© ♦© «© ■ i) W* MMHUIKM
Government Regulations 525 rodents or any other vertebrate animals which the EPA shall declare to be a pest. d. Herbicide. Any substance or mixture of substances intended for preventing, destroying, repelling or mitigating any weed. e. Nematocide. Any substance or mixture of substances intended for preventing, destroying, repelling or mitigating nematodes. f. Miticide. Any substance of mixture of substances intended for preventing, destroying, repelling or mitigating mites. g. Sterilant. Any substance or mixture of substances intended to destroy all forms of life, including micro-organisms, bacterial and fungal spores, and viruses. h. Disinfectant. Any substance or mixture of substances intended for destroying 100% of most vegetative bacteria—but not bacterial endospores. i. Sanitizer. Any substance or mixture of substances intended to mitigate the number of vegetative bacteria to a relatively safe level, normally about 5% or less of the original number. Inapplicable to aerosols as an indicator for minimal antimicrobial activity, if registered as economic poisons. j. Antiseptic. Any substance or mixture of substances intended for preventing, destroying, repelling or mitigating bacteria found on living tissue. The term is not applied to economic poisons, but only to bacterial suppressants regulated under the F.D.A. k. Germicide. Any substance or mixture of substances intended for preventing, destroying, repelling or mitigating all micro-organisms other than spores. In practice, generally considered as capable of destroying pathogenic bacteria. 1. Virucide. Any substance or mixture of substances intended for preventing, destroying, repelling, inactivating or mitigating viruses. This term must be modified for labeling purposes, as: "Virucidal against many viruses, such as Type 2 adenovirus, Influenza Aj, Vaccinia. Type 1 polio and Herpes simplex." The product must be shown effective against each virus listed. Auxiliary claim. m. Tuberculocidal. Any substance or mixture of substances intended for destroying 100% of Myobacterium tuberculosis — a species of Gram-positive bacteria which causes over 90% of tuberculosis infections in man. Auxiliary claim. n. Streptocidal. Any substance or mixture of substances intended for preventing, destroying or repelling 100% of most Streptococci, a genus of Gram-positive bacteria. Auxiliary claim. o. Staphylocidal. Any substance or mixture of substances intended for preventing, destroying or repelling 100% of most Staphylococci, a genus of Gram-positive bacteria. Auxiliary claim. p. Sporicidal. Any substance or mixture of substances intended for destroying bacterial endospores. Routine economic poisons are never sporicidal. q. Pseudomonacidal. Any substance of mixture of substances intended for preventing, destroying or repelling 100% of most Pseudomonas bacteria; a genus of Gram-negative rods often resistant to bactericides. Auxiliary claim. r. Mildewcide Any substance or mixture of substances intended for preventing, destroying, or repelling 100% of most fungi. Auxiliary claim. s. Plant Regulator. Any substance or mixture of substances intended through physiological action, to accelerate or retard the rate of plant growth or rate of plant maturation. (Not to include plant nutrients, trace elements, and the like.) The EPA refuse to accept extravagant, misleading or all-encompassing claims. Use of such words as "perfect" or "ideal" is disallowed. Specific directions must be provided for the product use, under which it will satisfy the label claims, up to a 95% confidence level. Impractical claims are rejected, such as "disinfects whitewall tires, awnings..." Hard-to- interpret statements are revised, often by adding words to obtain needed clarification. Claims such as "kills most bacteria" are revised to "kills most bacteria on environmental surfaces"; reflecting the fact that the authority of FIFRA Act does not extend to living things, specifically the skin and hair of animals, including humans, with the relatively unique exception of insect repellent compositions of all types. Insecticides are tested for efficacy using the Peet- Grady Chamber Method, and observing the behavioral characteristics of houseflies in this box at certain time intervals following introduction of a fixed amount of
526 The Aerosol Handbook spray. Results, at 5 min., 10 min., 15 min., and 24 hours, are compared with knock-downs obtained with an "Official Test Aerosol" standard. Other specific tests are also available, such as the "Cockroach Test". Insecticides containing new toxicants are required to undergo far more extensive testing for efficacy, safety and environmental compatibility. Several field tests are included in this program. As a result of such testing, first the toxicant, and then various formulas containing it, are registered with the EPA. Others who may desire to use the toxicant or the suggested formulations, must then arrange with the registrant to make the confidential EPA file available for review by the agency in processing further registrations. Minor changes, such as perfume or petroleum distillate level, will not jeopardize the registration. Propellent changes may be challenged by the EPA, if they feel that the effect on particle size will reduce the effectiveness of the formula to less than "O.T.A." levels. The USD A worked out various methods for determining the efficacy of disinfectants, during the 1960s, and handed them over to the EPA in 1970, when the FIFRA was transferred. The relative unreliability of any one is such that large numbers of replicates, sometimes hundreds, must be used to prove label claims to the satisfaction of the agency. Disinfectants have been divided into three classes, according to efficacy and intended use. In the terminology of the early 1970s these were "Class A" (with minimal claims), "Class B" (for general disinfection), and "Class C" (for superior disinfection in hospitals, clinics, veterinarian's offices, etc.). These general classes have survived into the 1980s, but the names have changed to more descriptive phrases. "Class A" hard surface disinfectants are known as those with "limited efficacy claims". The label must specify the major group of microorganisms against which it is effective, such as Gram-positive or Gram- negative bacteria. The test requirement involves the AOAC Germicidal Spray Products Test. Sixty carriers must be tested with each of three samples, representing three different batches, one of which is at least sixty days old. For Gram-negative claims they must be tested against Salmonella choleraesuis ATCC 10708, and for Gram-positive claims they must be assayed against Staphylococcus aureus ATCC 6538. The samples must kill 59 out of each set of 60 carriers in order to provide effectiveness at the 95% confidence level. "Class B" hard surface disinfectants are now known as those with "general or broad spectrum efficacy claims". Label claims of effectiveness as a "general" disinfectant, or representations that the product is effective against a broad spectrum of micro-organisms are acceptable if the product is proved effective against both Gram-positive and Gram-negative organisms. Using the AOAC Germicidal Spray Products Test, as above, sixty carriers must be tested with each of three samples, representing three different batches, one of which is at least sixty days old. As before, the samples must kill 59 or more out of each set of 60 carriers in order to be rated as effective at a 95% confidence level. ' 'Class C'' hard surface disinfectants are now known as those with ' 'hospital or medical environment efficacy claims". Such label claims will be accepted by EPA only for those products that have been demonstrated to be effective for general or broad-spectrum disinfection and additionally against the nosocomial bacterial pathogen Pseudomonas aeruginosa. Using the AOAC Germicidal Spray Products Test, as above, sixty carriers must be tested with each of three samples, representing three different batches, one of which is to be at least 60 days old, against each of the following: S. choleraesuis, S. aureus, and Ps. aeruginosa ATCC 15442. For any of these products substantiated label claims of effectiveness of the disinfectant against specific microorganisms other than the designated test microorganisms are permitted by EPA but not required, provided the targeted pest is likely to be present in or on the recommended use areas and surfaces and thus may present a potential problem. The effectiveness of disinfectants against specific microorganisms other than those named in the AOAC Germicidal Spray Test, AOAC Fungicidal Test, AOAC Tuberculocidal Activity Method, but not including viruses, must be determined by the AOAC Germicidal Spray Test, using ten carriers with each of two samples, representing two different batches, against each specific microorganism. Killing the test organism in all carriers is required. Plate count data, on appropriate culture media, must be submitted on each test organism to show that a concentration of at least 10,000 microorganisms survive the carrier-drying step, in order to provide meaningful results. In some cases, disinfectants and disinfectant cleaners may be designed to include uses on other than hard, non-porous surfaces, or applied for exposure periods longer or shorter than those specified in the standard methods. Labeling and testing may have to be revised to fit these other criteria. For a product tested with a
Government Regulations 527 residence time of ten minutes on a surface, the label must not state "instantly active", or "spray on surface and immediately wipe off with clean cloth". Instead, the necessary exposure time must be featured prominently on the label. For porous surface claims, the product must be tested using unglazed ceramic tile carriers, or if specific surfaces, such as wood or leather are listed, then testing must be done using these materials as carriers. If hard water is involved in the intended uses, as in cleaners, toilet cleaners or like products, then all claimed organisms must be retested using hard water to make sure they are still adequately controlled. Any disinfectant cleaner or cleaner-sanitizer designed to remove organic soil must be tested for efficacy by appropriate methods which have been modified to include a representative organic soil such as 5% blood serum. If the surface is heavily soiled, the label should include directions for cleaning it prior to the application of the pesticide-cleaner. In some instances, application of the disinfectant product will control the proliferation of microorganisms for a more- or-less specific time period, depending upon many conditions, such as type and porosity of the surface, type of bactericide, fungicide or other active ingredient(s), humidity and so forth. Where re-growth is possible within one month, the product label should state, "for continuing control re-spray every x-days''. Where control is obtained for over a month, the label may simply state "for continuing control respray as necesary", or words to that effect. If virucidal claims are desired, they must be supported by clinical data on at least one preparation against each of the viruses named on the label, run according to accepted virulogical techniques. Such tests are always performed at the larger microbiological ■laboratories and the cost can run to $600 or more per determination. Major changes often have to be made in label claims before submitted labels will be accepted for registration by the EPA. The following examples are typical of labels submitted by firms relatively inexperienced in label development. First we show the front and back label copy for a proposed disinfectant cleaner, theoretically submitted for approval under FIFRA. LABEL ONE Tomorrow's cleaner . . . For your bathroom. PP DISINFECTANT CLEANER HO. I SPRAY CLEANER WITH AMMONIA Cleans and disinfects most environmental surfaces on contact! NET WT. 20 OZ. (I lb. 4 oz.) WARNING: Contents under pressure, eye irritant. Keep from children's reach. Read carefully other cautions on back panel. Made by PETERSON/PURITAN, INC. Hegeler Lane, Danville III. 61832 EPA Reg. No Stock No P/P Disinfectant Cleaner No. 1 with Ammonia CLEANS. DISINFECTS AND DEODORIZES BATHROOMS DIRECTIONS: Shake well before ond during use. Point arrow on sproy button to red mork on rim. Sproy evenly, holding con 6 to 8 inches from surfoce to be cleaned. For control of mold and mildew, sproy all woshable surfoces thoroughly. Reopply as new growth appears. Allow foam to penetrote ond dissolve dirt, scums and stoins. Rinse clean with moist cloth, sponge or paper towel. No need to wipe dry. For chrome, simply rinse with water. * * * Cleaner is fine for ony household cleaning job, big or small. Its heovy-duty power formula lifts owoy most types of dirt and stoins; oil you hove to do is wipe. Never o fuss— never a muss. As it cleans it also disinfects. Kills most dangerous household germs, such as Staph, and Strep. Kills othletes foot fungus on household surfoces. Prevents mold ond mildew growth on hord, non-porous surfaces. Use it for bothtubs, wosh basins, bothroom tile, toilet surfoces, shower stolls, chrome fixtures, plostic counter tops, baked enamel surfaces, porceloin ond ceromic surfoces. ACTIVE INGREDIENTS: Sodium salt of 5-chloro-2-(2,4-dichlolophenoxy) phenol 0.05% Isoproponol 4.95% Diethanolomine-louric ocid omide 0.20% EssentiolOil 0.08% INERT INGREDIENTS* 94.72% 'Includes detergents and other cleoning ogents. WARNING: Contents under pressure, eye irritant. Contains strong detergents. Do not puncture or incinerate. Do not expose to heat or store above 120°F. In cose of contoct with eyes flood with woter, call physicion. Keep from children's reoch. Front Panel of Label as Submitted Back Panel of Disinfectant Label
528 The Aerosol Handbook EPA asked for the following changes: 1. Change "toilet surfaces" to "toilet seats". If the product is intended for use in the toilet bowl, directions must be expanded to include expelling the residual water over the trap prior to application of the product. 2. Additional data must be submitted to support the claim that the product kills athlete's foot fungus and Strep. 3. Perfumes or essential oils in quantity less than 0.2% are considered to be Inert Ingredients and must be included under "Inert Ingredients." 4. Tetrasodium ethylene diamine tetraacetate is considered to be an Active Ingredient and must be so listed. 5. The effectiveness of products against mold and mildew organisms depends to a significant extent on the nature of the surfaces or articles to be treated. The product must be tested, using the appropriate method, if claims of this nature are made. Test requirements can be minimized by selectively naming surfaces or articles which it is claimed can be treated by the product. NET WT. 12 OZ. P/P INSECTICIDE NO. I Based on SBP 1382; a new synthetic pyrethroid for controlling the following household flying and crawling insects: house- flies, mosquitoes, gnats, wasps, roaches, ants, earwigs, spiders, grain mites, sowbugs and centipedes. ACTIVE INGREDIENTS: *t(5-Benzyl-3-furyl),methyl 2, 2-dimethyl-3-(2-methyl propenyljcyclopropanecarboxylate —- 0.250% Related compounds 0.034% Aromatic petroleum hydrocarbons 0.332% Petroleum Distillate - 19.374% IN ERT INGR ED IENTS: 80.010% *Cis/trans isomers ratio: max 30% (=*=) cis and min. 70% (=■=) trans. 'U.S. Patent No. 3,465,007 (Safe when used as directed on the label) CAUTION: KEEP OUT OF THE REACH OF CHILDREN. Avoid contamination of feed and foodstuffs. Cover or remove all fishbowls. Contents under pressure. Do not expose container to temperatures above I20°F. Never throw container into fire or incinerator. Non-Flammable Made by PETERSON/PURITAN, INC. Hegeler Lane, Danville III. 61832 6. If claims are made for control of mold or mildew, label should read "spray all hard, non-porous surfaces" not "spray all washable surfaces". 7. The results of a flame extension test on the product are required to evaluate its fire hazard. 8. Laurie diethanolamide must be declared. 9. Objection is raised to the statement. . ."with ammonia". . . which is considered misleading in that undue attention is focused on one ingredient when in fact that ingredient may be present in such a small amount as to be of no practical value in the product. 10. The front panel cautionary statement should be changed to read "Keep Out of Reach of Children". 11. The following statements should be added to the precautionary section: (After the statement "Eye Irritant".) (a) If in contact, flush thoroughly with water. Get medical attention if irritation persists. (b) The statement "Contains Nitrite" in close proximity to the ingredient statement. DIRECTIONS FOR USE Remove protective cap. Aim spray opening away from person. Push button to spray. FOR HOUSEFLIES, MOSQUITOES AND GNATS: Close all doors and windows. Point nozzle upward, direct the spray mist to all parts of the room, especially windows and other light sources which attract insects. Fill the room with mist, then leave the treated area. Keep the room dosed for at least fifteen minutes. Ventilate the room when treatment is completed. WASPS: Application should be made in the late evening when insects are at rest. Spray liberally into hiding and breeding places, contacting as many insects as possible. Repeat as necessary. FOR CRAWLING INSECTS: Roaches, earwigs, grain mites, sowbugs, spiders and centipedes: Spray thoroughly into hiding places, such as cracks, crevices, moist areas, openings around pipes and sinks, under refrigerators, baseboards, and storage areas. Spray directly on insects where possible. Repeat as necessary. ANTS: Spray trails, nests and points of entry. Spray on ants where possible. Repeat as necessary. EPA Reg. No. I 1525-1 Part No Insecticide Label as Submitted Back Panel of Label as Submitted
Government Regulations 529 12. The child hazard warning should immediately precede the signal world and other statements of hazard. 13. The contents declaration should be moved into the bottom 30% of the front label panel. 14. The ingredients statement must be placed on the front label panel immediately following the product name. Similarly, a proposed label for a typical insecticide was submitted to the EPA with front and back panels as shown in Label II on page 528. The EPA asked for the following changes before the label could be accepted for registration: 1. The claim that the product is "non-flammable" would have to be either proved or omitted. The flame projection test result of 7 " indicates that flammable components and characteristics are present. 2. Deletion of the claim "Safe when used as directed''. The EPA considers that the use of the word "safe" or similar claims detracts from the statement of hazard. 3. The signal word "WARNING" must follow the child hazard warning. 4. Underlining must be removed from "Active Ingredients". In the final label the words "Active Ingredients" and "Inert Ingredients" must be of equal type size, placement, margin, color and readability. 5. The ingredients statement should appear directly below the product name. 6. The contents declaration must appear in the bottom 30% of the front label panel. 7. Permission should be obtained from the suppliers) to authorize use of their confidential formula^) in support of the product's registration. Alternatively, the suppliers) should be asked to submit to EPA their complete formula(s) giving names and percentages of both active and inert ingredients. 8. Under the claim for control of houseflies, mosquitoes and gnats, directions should be revised to read "direct the mist to all parts of the room especially windows and other light sources which attract these insects.'' Federal Environmental Pest Control Act of 1971 (FEPCA) About 1970 it was recognized that FIFRA regulations were designed to provide firm registrational and labeling control of pesticide products, but that they tended to leave broad environmental and public protection issues alone to a great extent. These omissions were addressed by HR 10729 with the aim of expanding FIFRA coverage. New legislation has now acted to: a. Create two classes of pesticides: those for general use and mose for restricted use. "Restricted use" products can be applied only by licensed pesticide treaters and applicators. b. Require factory (establishment) registration and permit factory inspections. c. Require consideration of environmental factors during the process of registration. d. Permit a hearing and review in the event the EPA turns down a request for the registration of a new product. In addition, the applicant may ask the National Academy of Science to pass judgment on relevant scientific issues. e. Provide specific federal pre-emption of state and local laws regarding the labeling and packaging of pesticides. However, the states would be permitted to ban the shipment of any restricted pesticide within their borders for cause. f. States would be permitted to adopt local regulations governing pesticides, which might be more stringent than the federal controls. The concept that the states may be permitted to develop pesticide regulations different from mose in use by the federal government is one that is particularly onerous to the pesticide industry. Manufacturers, marketers and users feel quite strongly that regulations, standards and registration procedures should be uniform throughout the U.S.A. to facilitate the manufacture, formulation, packaging and distribution of pesticide chemicals—in fact, all chemicals and commodities. The industry, therefore, strongly suppports the concept of federal preemption in this area. While the industry accepts the idea that the states may have different local needs and should have something to say about uses and applications, it is felt that they should not participate in such areas as registration, labeling, standard-making and regulations different than those at the federal level. Industry feels that labels Next Page
Government Regulations Previous Page 12. The child hazard warning should immediately precede the signal world and other statements of hazard. 13. The contents declaration should be moved into the bottom 30% of the front label panel. 14. The ingredients statement must be placed on the front label panel immediately following the product name. Similarly, a proposed label for a typical insecticide was submitted to the EPA with front and back panels as shown in Label II on page 528. The EPA asked for the following changes before the label could be accepted for registration: 1. The claim that the product is "non-flammable" would have to be either proved or omitted. The flame projection test result of 7 " indicates that flammable components and characteristics are present. 2. Deletion of the claim "Safe when used as directed''. The EPA considers that the use of the word "safe" or similar claims detracts from the statement of hazard. 3. The signal word "WARNING" must follow the child hazard warning. 4. Underlining must be removed from "Active Ingredients". In the final label the words "Active Ingredients" and "Inert Ingredients" must be of equal type size, placement, margin, color and readability. 5. The ingredients statement should appear directly below the product name. 6. The contents declaration must appear in the bottom 30% of the front label panel. 7. Permission should be obtained from the suppliers) to authorize use of their confidential formula^) in support of the product's registration. Alternatively, the suppliers) should be asked to submit to EPA their complete formula(s) giving names and percentages of both active and inert ingredients. 8. Under the claim for control of houseflies, mosquitoes and gnats, directions should be revised to read "direct the mist to all parts of the room especially windows and other light sources which attract these insects.'' 529 Federal Environmental Pest Control Act of 1971 (FEPCA) About 1970 it was recognized that FIFRA regulations were designed to provide firm registrational and labeling control of pesticide products, but that they tended to leave broad environmental and public protection issues alone to a great extent. These omissions were addressed by HR 10729 with the aim of expanding FIFRA coverage. New legislation has now acted to: a. Create two classes of pesticides: those for general use and those for restricted use. "Restricted use" products can be applied only by licensed pesticide treaters and applicators. b. Require factory (establishment) registration and permit factory inspections. c. Require consideration of environmental factors during the process of registration. d. Permit a hearing and review in the event the EPA turns down a request for the registration of a new product. In addition, the applicant may ask the National Academy of Science to pass judgment on relevant scientific issues. e. Provide specific federal pre-emption of state and local laws regarding the labeling and packaging of pesticides. However, the states would be permitted to ban the shipment of any restricted pesticide within their borders for cause. f. States would be permitted to adopt local regulations governing pesticides, which might be more stringent than the federal controls. The concept that the states may be permitted to develop pesticide regulations different from those in use by the federal government is one that is particularly onerous to the pesticide industry. Manufacturers, marketers and users feel quite strongly that regulations, standards and registration procedures should be uniform throughout the U.S.A. to facilitate the manufacture, formulation, packaging and distribution of pesticide chemicals—in fact, all chemicals and commodities. The industry, therefore, strongly suppports the concept of federal preemption in this area. While the industry accepts the idea that the states may have different local needs and should have something to say about uses and applications, it is felt that they should not participate in such areas as registration, labeling, standard-making and regulations different than those at the federal level. Industry feels that labels
530 The Aerosol Handbook registered by the EPA should either be accepted for state registrations, or else made exempt from state registration requirements. Starting about 1979 there have been several problems with the FIFRA implementation at both the federal and state level. Congress is attempting to deal with these situations via HR 5203 and other bills. By 1982 at least six states have attempted to expand their pesticide programs to exceed the federal requirements. California, in particular, has imposed unnecessary and burdensome regulations upon the industry, requiring a second registration (by CDFA) before marketing can begin. One insect spray registered by the EPA in 1976 required 594 days for the CDFA to register it. Lengthy registration delays may result from the slightest label changes, and it has taken from 15 to 24 months to add a new use or a new pest to the California label, even after approval by the EPA. California has sometimes changed test data requirements in mid-stream, resulting in delays and increased data requirements by the registrant. Attempts are now being made to amend FIFRA's Section 24(a) which covers the authority of the states. Two key provisions can be cited. A state's request for data, which does not come within the realm of special local concern data, is to be reviewable by EPA, and products in this category are to be granted registrations pending further review. Also, an obligation is imposed upon the states to act on most registration applications within 60 days of receipt or the product is deemed registered. It can finally be noted that California now exacts a registration maintenance fee on an annual basis, plus another, based upon the number of units sold within the state and the retail price of each. The annual fees are paid by the registrant and the per- unit fees are handled by the marketer. They reportedly go into the financial support of the state program for registration, plus safety educational activities in the pesticides area. Where pesticides are to be used in or around food handling establishments, a USDA registration is required in addition to the EPA registration. This is normally done by coordinating the activities of these two authorities at the same time, advising each of the progress of the other. The USDA Registration No. may then appear on the label of the finished product. Various federal and state agencies, as well as universities, may analyze the active ingredient levels of insecticides and disinfectants and report their findings to the marketer. Because of the high cost of some insecticide ingredients (over $200/lb, or $440/kg) most of the activity centers on insect sprays. Companies are then often obliged to respond in a fixed time period, to show that the assay is correct. In some cases, the insecticidal activity may be questioned, aside from any percentage considerations, and here the response is normally the submission of the results of the Aerosol and Pressurized Spray Insecticide Test (Large Group Method), where the product is assayed in comparison to the Official Test Aerosol (OTA-II). The Toxic Substances Control Act Added powers have been provided to the EPA under this complex legislation. Some are: a. Restriction of prohibition of the use of hazardous chemicals in industry or commerce if they threaten the health of the environment. b. Premarket clearance of all new chemicals and certain existing products. c. Power to summarily seize chemical substances deemed to be imminent hazards. The EPA enjoyed these powers with respect to pesticides, but the TSCA greatly expands these prerogatives. The activities of the agency in controlling 2,4-D and 2,4,5-T type herbicides is well known and has been linked to almost unimaginable costs to both government and industry. The CSMA has now completed a massive study of the effects of TSCA and Premanufacture Notification (PMN) on innovation in the chemical specialties industry. The so-called Kirschner Report of 1981 showed that ingredient suppliers produced 26% fewer new substances since 1979, that 72% of these surveyed firms planned to reduce such new substance developments, and the cost of filing a PMN averaged $16,000 plus at least $5,000 in toxicity tests. The CSMA has used this documentation to suggest changes under Sections 4 and 5 of TSCA, which would either limit the amount of information required for a PMN (facilitated by using a simpler form), or that flexibility could be achieved by using model protocols rather than set guidelines for tox- icological testing. The agency should also establish exemptions for substances with small risks and those chemicals not worth the expense of a full premanufacture review. During mid-1981 the EPA proposed further testing of methylene chloride, 1,1,1-trichloroethane and nitrobenzene under TSCA Section 4 test rules, for a total cost of up to $2 million. In the case of methylene chloride, such tests as acute toxicity to birds and
Government Regulations 531 bioconcentration in plants seem to have little practical merit. By this time, methylene chloride may well be the most thoroughly toxicologically tested of all known chemicals. It has had an exceptionally good record in these tests. The value of the proposed tests under TSCA may be questioned both in general and from the standpoint of the very minimal exposure levels of the target life forms. The Resource Conservation and Recovery Act (RCRA) This act was signed into law in 1976, and concerns the disposal of hazardous waste materials. Sub-title C of the act contains the famous "cradle-to-grave" approach of tracking and regulating hazardous waste from the generator to the transporter and to the ultimate disposal site. Hazardous waste regulations were proposed in 1978 by EPA. They contain a definition of "hazardous waste" based on criteria covering ignitability, corro- sivity, reactivity, and toxicity. Specific chemical wastes are also cited as hazardous. Standards covering storage facilities and disposal sites are included in the proposed regulations. Any person generating, transporting, treating, storing or disposing of a hazardous waste must file a preliminary notification with EPA. Wastes that are not "hazardous" are still regulated under RCRA. Strangely enough, aerosols are regulated under the broad category of "solid waste", which includes solid, liquid, semi-solids or contained gaseous materials. As mentioned in the chapter on Aerosol Flammability, the aerosol dispenser as such is not considered hazardous, but the contents may be if they are "Flammable" or "Extremely Flammable", caustic (as in some oven cleaners) or relatively poisonous. Because of the burdensome requirements, there has been a marked decrease in the number of disposal sites handling hazardous wastes, resulting in higher disposal prices and more paperwork. Operators of disposal sites assume certain risks. For example, in 1981 a site near Wilson- ville, IL was closed down by an action of law as a' 'common nuisance", after five years of operations. The site was operated by SCA Services, Inc., the nation's third largest waste management firm, with 1980 revenues of $230 million. Nevertheless, the business of waste disposal is increasingly lucrative under TSCA. The Chemical Waste Management Division of Waste Management, Inc.—the largest firm in this business—has 30% of the chemical waste disposal business (in 1981 and 1982) and is expected to grow by 30-35% during each of the next five years. A key to their success was the foresight to acquire large, hazardous waste landfill capacity ahead of time. In September 1980 Congress passed the Superfund Hazardous Waste Clean-Up bill to assist RCRA in its waste management activities. As an example, iso- butane is considered a hazardous waste item (within a specific listing of about 40 chemicals), and the producers must forward a fee to go into the superfund according to the amount sold each quarter. The fee is less than 1 % of the selling price, so the impact upon the aerosol industry is negligible in this case. Clean Air Act This act was initiated in 1977, to protect and enhance the quality of the nation's air resources so as to protect the public health and welfare and the productive capacity of its population. This act was the one invoked during the CFC/ozone controversy. In time, it may be used to control the emission of hydrocarbon gases at filling establishments. The average filler loses 7 to 10% of his hydrocarbon propellent purchases into the atmosphere, from a variety of leakage points and operations. Where products such as shave creams are filled, because they have so little propellent in the formula, the loss rate for the filling operation may get as high as 25% or so. The entrapment or burning-off of hydrocarbon vapors is impractical, except that a catalytic combustion system might be placed in the venting system of gas houses, at considerable expense, to change this portion of the loss into innocuous CO2 and water vapor. Another long-term problem attaches to the production of GK-45 and similar Flowed-In™ valve mounting cup gaskets under the CAA, since toluene is lost into the air during the heat-curing operations. This is one of the rationales used by Precision Valve Corp. in pioneering their polyethylene sleeve gasket, since here no curing stage is involved. PVC's Aeroco Division, where these operations are done, is located in New Jersey, which has been an extremely difficult state to deal with on clean air and environmental issues. Under Section 112 of the act, there is a listing of specific hazardous air pollutants. As of 1982 it included asbestos, beryllium and its compounds, mercury and its compounds, vinyl chloride monomer, radionucleides, benzene and inorganic arsenic compounds. The listing will undoubtedly be lengthened in the future.
532 The Aerosol Handbook CONSUMER PRODUCT SAFETY ACT OF 1972 This act was created to "protect the public against unreasonable risk of injury associated with consumer products . . . and ... to assist consumers in evaluating the comparative safety of consumer products." The act is designed to control the safety aspects ofthe dispenser and contents of "household products", but it has been applied in a broader sense to cover packages for all classes of consumer products. The "household products" area specifically excludes products that fall under the FDA, the EPA, and the Treasury Department (under the Alcohol, Tobacco and Firearms Act - AT&FA), as well as those that are produced only for institutional and/or industrial uses and will never get into domestic areas. The Federal Hazardous Substances Act of 1960 Originally designated as a labeling act, the FHSA has taken on larger regulatory parameters. It has, as its principal thrust, the protection of the consumer by means of regulating the precautionary labeling on the container. Specific definitions and test methods are described for hazards such as toxicity, corrosivity, irritancy, sensitization, flammability, pressure generation and radioactivity. Aerosol formulas may become involved with all of these hazards except the last. Specific hazards are defined in a cursory fashion as follows, but for a more precise rendering one must refer to the official interpretations ofthe act: a. Toxicity Products which are classified as highly toxic are required to carry warnings of a strong character and those classed as toxic must carry modified warnings. Divisions are made based upon LD50 or LC50. The LD50 is the weight ofthe substance in mg related to the kg weight ofthe test animal, which results in the death of 50% ofthe animals. The LC50 indicates the concentration of a gas or mist of the product in air which results in the death of 50% of the test animals. b. Irritant Irritants are classified on the basis of a numerical score determined by conducting prescribed patch tests on the skin or albino rabbits. A score of higher than 5 classifies the product as a primary irritant. Eye irritation ratings reflect the irritational effect of the substance in the eyes of these rabbits. c. Corrosivity A product is corrosive if it causes visible destruction or irreversible alteration of the skin tissues at the point of contact. d. Strong Sensitizer A product that produces an allergenic sensitization in a substantial number of persons who come into contact with it. (Also covered in FDA regulations, Sec. 191.6) e. Flammability "Extremely Flammable" aerosols are those where, in the flame projection test, a flashback (a flame extending back to the dispenser) is obtained at any degree of valve opening, and the flashpoint, by the Modified Tag Open Cup Flashpoint Test, is less than 20°F (-6.7°C). '' Flammable'' aerosols are those where, in the flame projection test, a flame projection exceeding 18" (457 mm) is obtained at full valve opening or a flashback (a flame extending back to the dispenser) is obtained at any degree of valve opening. f. Pressure Generation The particular definition applicable to aerosols is that a product is hazardous if it comprises the contents of a self- pressurized container. (All aerosols are hazardous from a pressure generation standpoint and require precautionary labeling accordingly. However, the pressure generating substance need not be identified on the label.) In addition to these classes of hazardous materials, there are a number of specific hazardous materials identified in the regulations which, above certain percentages, must be identified on the label. They include petroleum distillates and turpentine, in amounts of 10% or more, methanol over 4%, sodium hydroxide or potassium over 2%, ethylene glycol and so forth. Labeling provisions are set forth, stating that the immediate package label must contain the name and place of business of that manufacturer, packer, distributor or seller, the common name of each component that contributes to the hazard (aerosol propellents exempted), precautionary measures to be taken, first aid instructions when necessary and appropriate, and the statement, "Keep out ofthe reach of children" or the practical equivalent. For products designed for use by children this last caution would be revised to "Keep out ofthe reach of children except under adult supervision." Where the only hazard is that the contents are under pressure, under the regulations in Chapter II, Subchapter C, Part 1500.130(b), the label must state: "WARNING - CONTENTS UNDER PRESSURE Do not puncture or incinerate container. Do not expose to heat or store at temperatures above 120°F. Keep out ofthe reach of children." (Note: 120°F = 48.9°C). If desired, the word "CAUTION" may be substituted for the word "WARNING".
Government Regulations 533 If a particular hazard has been identified by clinical tests, then additional information must be presented on the label. If the aerosol is "highly toxic", such as certain tear gas products used for personal defense, the label must contain the words "POISON" and "DANGER" on the principal display panel, followed by such phrases as, "Keep out of the reach of children. Contains (name of toxic chemical). See cautions on back panel." The back panel must then contain a section titled "Precautions", where first aid and safety information is provided. In many cases the phrase "Cannot be made non-toxic," is included. The minimum labeling for an "Extremely Flammable" areosol will involve statments such as: "DANGER - EXTREMELY FLAMMABLE" (principal display panel - 18 point type), "Keep out of the reach of children" (principal display panel - 10 point type) and "See precautions on back panel" (principal display panel - 10 point type). On the back panel, in not less than 10 point type, "Keep away from heat, sparks or open flame. Use with adequate ventilation. Do not puncture or incinerate container. Do not store at temperatures above 120°F" (Note: 120°F = 48.9°C) If desired, all the precautions may be placed on the principal display panel. The signal word and statement of the principal hazard(s) must appear on the front panel of the label, along with the words "Keep out of the reach of children." and the reference "See other cautions on back panel.", or the equivalent. The signal word must be in capital letters and in not less than 18 point type (6.35 mm high), while the statement of hazard must be in a minimum of 12 point type size (4.23 mm high) and the other statements must be in not less than 10 point type size (3.52 mm high). Other precautions, usually found on the back or side label panel, must be at least 10 points (3.52 mm high). An exception is made in the case of small labels, but in no event may the type size be smaller than 6 point (2.12 mm high). The Poison Prevention Packaging Act of 1970 This is one of the least known acts administered by the CPSC, but an important one for the aerosol industry. It establishes regulatory standards for special packaging of any household substance dangerous to children. Sometimes it is erroneously called the Child Resistant Closure Act, since these closures are its most visible attribute. The act is specific and detailed, and one which requires close analysis during product development. Household product aerosols are subject to "special packaging" if they are corrosive to the eye or skin, have an acute dermal LD5o of 2000 mg/kg or less, have an inhalation LC50 of 2 mg/liter or less or have an acute oral LD50 of 1.5 g/kg or less. The Commission may find that products other than household products may qualify for "special packaging", wherever they present a serious hazard of accidental injury which such packaging might act to reduce. Finally, should a product be so dangerous that "special packaging" is deemed insufficiently effective in removing or reducing the hazard, the Commission may ban them. For example, this was done in the case of a water repellent based upon an organo-titanium (IV) compound dissolved in a highly flammable solvent/propellent system, and designed to be sprayed on very large areas of concrete or concrete blocks. After several explosions, caused by vapor ignitions from nearby pilot lights or furnaces, the product was banned. Later it returned to the market in a modified formula. The testing protocols for child-resistant closures have already been described. They involve 200 children and 100 adults of specific age and sex distributions. The full protocol test currently costs about $5,000 (1982), and a "half-size" partial protocol screening test runs about $3,600 (1982). Firms such as the California Consultants Testing Division (Woodbridge, CA 95258) are able to perform these studies. Rather interestingly, a machine has been developed by the National Bureau of Standards (NBS) and the CPSC to test child-resistant closures. This tester can be used in screening tests, but the full human testing program is still required. The CPSC plans to use the device for testing child-resistant closures on the market, to make sure they are performing as stipulated. Blueprints are available from CPSC. Most aerosol formulations are outside the realm of child-resistant packaging requirements. Some that are affected, however, include caustic oven cleaners, a few heavy duty or high-alkaline cleaners (such as some toilet bowl cleaners), personal protection aerosols and some paint strippers (such as those that contain both methylene chloride and a gelling agent). Both EPA and CPSC product categories are subject to "special packaging"; other aerosols are not. The CPSC National Electronic Injury Surveillance System (NEISS) Early in the 1970s the CPSC set up a "NEISS Study" system, where 119 hospitals and selected doctor's emergency rooms reported a variety of accidents
534 The Aerosol Handbook Table XI NEISS* Results on Aerosol Injuries; 1974 - 1978 With Estimated U.S.A. Totals Year 1974 1975 1976 1977 1978 Actual Number of Statistical Accidents Reported Adjustment Factor 162 250 229 233 165 27.5 22.6 25.3 26.0 25.4 Estimated U.S.A. Total 4,457 5,656 5,798 6,059 4,191 'National Electronic Injury Surveillance System. caused by various products. With reference to accidents involving aerosols, data is summarized in Table XI. About 25% of the injuries treated in emergency rooms are due to minor dermatitis and conjunctivitis. Minor chemical burns (caustic, etc.) formed the second largest category. Taking the 1978 inventory as an example, reported deaths due to aerosols were listed by the CPSC as 9, due to intentional inhalation abuses, one, due to an explosion, and one, due to inhalation where there was no intentional abuse. The industry has always been concerned about these particular inputs of the NEISS reports. Much of the data is vague and much is improperly categorized. For example, a laceration could result from a thrown aerosol can. A baby's broken finger resulted from dropping an aerosol can on it. The inclusion of these accidents in the overall statistics make aerosols seem more hazardous than they really are. The statistical treatment of the data has been the subject of much criticism, and finally, these data do not give any hint of the severity ratings, simply numbers of visits. It is easily shown that aerosol-related accidents are, on the average, far less severe than many other types, such as those caused by power mowers. Products that pose greater risks to consumers than aerosols include cleaning compounds, household products in general, fuels, paints, solvents, waxes and polishes, pesticides, cosmetics and even prescription drugs. In this sense the NEISS report is positive in that it shows that aerosols are usually the safest way to present a product to consumers. Finally, according to the NEISS data, even when an aerosol is misused, the chances for a person suffering an injury are less than one per 300,000. According to present CPSC Chairman Nancy Steorts, the recent decision to cut the agency's budget by 30% in fiscal 1982 will have its effect in reducing the NEISS program. The number of reporting hospitals will be diminished. This and other modifications in the system will save the agency over $500,000 and 100 staff- months of time. Some of the savings will be redirected to allow for added special hazard identification studies. CPSC Aerosol Ingredient Labeling Program Since 1976 the CPSC has made use of a product ingredient data base called the CCHI (Chemical Consumer Hazard Information) file, which is referred to more commonly as the Auerbach file, from the contractor who developed it. Formulation data on some 8200 household products is listed and available, including well over 100 aerosols. Since the half-life of formulary data is about ten years, and the file was compiled in 1973 and 1974, the data are rapidly becoming obsolete. In 1981, the CPSC announced plans for a new survey (sometimes called CHIP II) to update their file at a cost of about $100,000. As before, the collected data would be used by those trying to establish what chemicals were being used in household products, various formula trends and so forth. Industry has always objected to this overall activity, partly from a finding that numbers of confidential formulations were made public as a result of the Auerbach survey. Obviously, another route toward the unveiling of formulations is for the CPSC to require formula labeling, much as the FDA now requires it for foods, drugs and cosmetics, and as the EPA requires it for pesticides. In 1980, the CPSC launched a formal investigation of such labeling. Their options were to require only propellent labeling, full ingredient labeling, the labeling only of hazardous ingredients, or no labeling. Full ingredient labeling, patterned after the semiquantitative "descending order of percentage by weight'' method used by the FDA, seemed to be their choice. The staff estimated that the proposed regulation would affect 5,500 different type products with a sales volume of 800 billion units annually and would cost industry only about $2.8 million (1980 dollars). There was also a suggestion that the CPSC might want to demand pre-clearance for such labels, which, technically, they have no authority to implement. Pre- introduction testing and certification would be a halfway measure. The implementation of such a labeling program would first require a multi-year cooperative project, where industry and CPSC personnel would develop a huge list of standard names for household product
Government Regulations 535 ingredients, much like the CTFA did in developing their CTFA Cosmetic Ingredient Dictionary, in cooperation with the FDA during the early 1970s. (This big book of thousands of ingredients sold for $160 including shipping in 1982). Possibly because of a delayed realization of the true costs and time involved in such an undertaking, the CPSC has not done anything substantive during 1981 and 1982 in this area. However, this hiatus period may only be due to recent budgetary constraints, and perhaps the recognition of higher priority items by the agency within that framework. Other CPSC Activities During the beginning of the 1980s a great deal of attention has been focused on chronic hazards. Under new legislation, the CPSC has to set up a Chronic Hazards Advisory Panel (CHAP) to review proposed rulemaking relating to chronic hazards defined as consisting of cancer, birth defects or gene mutations. The panel of seven persons will be drawn by the President of the National Academy of Sciences from state employees, academia and other non-federal and non-industry experts. The panels are ad hoc, designed to handle an existing investigation and then dissolve. The questions of chronic hazard are also addressed under the EPA's TSCA program and under OSHA mandates, with OSHA undoubtedly having assumed a lead role in cancer policies. During late 1981, the CPSC became involved in a new issue: indoor air pollution. During periods in winter when houses and offices are tightly shut, it was found that build-ups of formaldehyde, carbon monoxide, hydrocarbon carcinogens such benzopyrene, nitrogen (IV) oxides (NO2/N2O4) and even traces of radioactive radon gas, could take place to the extent where physiological or medical problems would result. The well-sealed house of the 1980s was perhaps 4 to 10 times as tight as the average house of the 1970s, so that the rate of air flow was reduced to only about 2 to 5 turnovers in a day. Under these conditions, a number of chemicals produced or released in situ were said to cause such nagging symptoms as "perpetual cold", headaches, respiratory problems, colds, skin rashes, eye irritation, lethargy, dizziness, memory lapses and cancer. Formaldehyde was the most worrisome air pollutant, seeping into the confined air space from urea-formaldehyde insulating foam, particle board, rugs and carpets, clothing and specialty chemicals. The CPSC acted to ban all new uses of urea-formaldehyde insulation. Some aerosol formulators have replaced formaldehyde with other broad spectrum microbicides in such products as fabric finishes, starch, various lotions and creams. Some marketers have considered replacing the usual weekly formaldehyde bactericidal treatment of de-ionizer beds with weekly treatments using some other broad-spectrum bactericide. . . .not because the formaldehyde will enter formulated products (it is all flushed down the drain) but from a sense of responsibility to personnel in the compounding area. Various articles on indoor air pollution also recite aerosols as culprits, causing various chemicals to enter the air, so that they are breathed by everyone in the building before they finally circulate to the outside. Actually, after normal spraying and distribution, aerosol ingredients generally drop into a concentration range of about 100 ppt to 100 ppb in the confined airspace, where most of them cannot even be measured with present-day instrumentation. There does not seem to be any ready or realistic solution to the "aerosol problem", if indeed there is one. The Occupational Safety and Health Act of 1970 This act was passed in order to better ensure the safety and health of workers. It is administered by the Occupational Safety and Health Agency, within the Department of Labor. They are authorized to require labeling of industrial products, to set standards for chemical exposure levels, to investigate worker grievances relating to health and/or safety, to perform inspections of suspect plants and to cause employers to provide workers with detailed information regarding the products they are asked to work with. During 1979, OSHA conducted 58,000 inspections, wrote out 132,000 violations and assessed fines of over $25 million. One of their inspections almost invariably results in substantial expenses to the business involved, for the correction of some purported violation (written or verbalized), or for the preparation of formal responses to prove innocence. In one plant, a group of vengeful employees showered the local OSHA office with so many grievances that almost 200 inspections were initiated in one year alone, causing such heavy distraction of management that profits sagged seriously and were a major factor in the closing of that operation in 1982. In 1980, OSHA published their second cancer policy, a 100 page document in 45 Federal Register Part
536 The Aerosol Handbook 5001 titled "Identification, Classification and Regulation of Potential Occupational Carcinogens". An amendment was published in 1981 (46 FR 4889), and further rulemaking was under study (47 FR 187) in 1982. Thus far over 250,000 pages of hearing testimony and an awesome volume of written submissions have resulted, but the legal battle will probably not be as difficult as was the one over OSHA's first carcinogen policy, where over two years of hearings resulted and paperwork was generated by the truckload. Some of the industry points are that OSHA should not attempt to define scientific criteria, but rather, should define guidelines. Similarly, mandating techniques for defining carcinogens is poor science, since this is a fast changing and developing field. The OSHA goal appears to be to establish the nation's first overall cancer policy. If this is the case, the White House Office of Science and Technology, National Academy of Sciences (NAS), Interagency Regulatory Liaison Group (IRLG) and several other bodies should be consulted for the best overall approach. Under the Carcinogen Policy (as it is usually called), OSHA moves through three stages in the screening of potential carcinogens for regulatory action. First, they briefly review certain available data and publish a Candidate List. Then they conduct a more thorough search and assemble two Priority Lists often substances each. And finally, OSHA selects high priority substances for rulemaking. As of mid-1982, OSHA has published a Candidate List, but has not issued a Priority List. Industry's concern with these compilations is that they could readily develop into blacklists that are unsupported by an adequate review of the data. (The EPA also publishes so- called candidate lists for interim review.) In all probability, OSHA may abandon these potentially damaging lists as they reconsider taking a generic approach to carcinogeniety. The OSHA Carcinogen Policy's provision that exposure limits for Category I carcinogens must be set at zero if a substitute is available for one or more uses is a "zero-risk" idea. This is inconsistant with Executive Order 12291 and its cost/benefit considerations, also with the Supreme Court's ruling in the celebrated benzene case in 1980. Any publication of Category I or Category II lists will probably be contested by industry. A problem in this area is that the EPA's TSCA policy covers much of the same responsibilities in its aim of preventing unreasonable risks of injury or health from exposure to toxic substances. TSCA personnel, working with OSHA people, are assembling Category I and II listings which will probably total some 3,500 chemicals—from 6 to 9% of all chemicals in commercial use, according to definition. If either agency eventually require the labeling of industrial containers of these substances as "DANGER" — Contains (Chemical Name) — Cancer Hazard", there will be an unprecedented level of resistance by the business community. Behind all this there are some deep-seated dichotomies. For example, OSHA has suggested that from 60 to 90% of all cancers in the U.S.A. are associated with environmental factors caused by industrial substances and pollution. Industry feels the figure is more properly less than 5% and receding; that personal habits — smoking, drinking alcoholic beverages, eating charred meat or caramelized glazed doughnuts—are more important by far. Also, both OSHA and TSCA consider that if a substance produces cancer in a test animal, regardless of dosage level or time of administration, that it should be sanctioned. Industry feels otherwise, recognizing that there are broad response differences between animals and that humans appear to be less susceptable to carcinogens in general. These points are more fully described in the chapter on Aerosol Toxicology. OSHA is highly interested in having industry provide employees with data and training that may act to help them avoid health and safety problems. The Materials Safety Data Sheet (OSHA Form 20) was designed to supply toxicological data and precautions against undue exposure to specific chemicals. Copies of these forms (for individual chemicals and also for aerosol formulations) are shown in the Aerosol Toxicology chapter. In practice, firms that consistantly deal with 1000 to 3000 chemicals, such as aerosol fillers, find it difficult to produce these forms for all their chemicals and finished formulations. When they do, the forms seem to go into the back of a cabinet and be largely forgotten by the employees they were designed to help. The OSHA health standards, such as the benzene standard 1910.1028, the coke oven emissions standard 1910.1029, and so forth have quite specific and detailed requirements for the instruction and training of employees exposed to these hazards. Broader safety standards, such as the respiratory protection standard 1910.134, also contain references to instruction and training. OSHA's Employment Safety and Health Guide, Chapter VIII, Part 4360.1 Section 5(a)(1) is being used increasingly by OSHA Compliance Officers as the basis for violations for employers who fail to train
Government Regulations 537 and properly instruct the employee in the hazards associated with his/her work. For example, under the General Duty Clause, an aerosol filler must advise an employee about the possible hazards of hot tank operations, the flammability of various solvents used in compounding, the danger of hand-puncturing power-aerosol units and even, in one case, the danger of deliberately inhaling nitrous oxide (N2O) gas to achieve a psychodelic high. During 1981 OSHA proposed either mandatory standards or guidelines to protect laboratory workers against exposure to toxic chemicals. Part of the background was a recognition that many laboratory and research chemicals are more toxic than those used in industry in general, and that the greater professional training of chemists and technicians may not be a sufficient offset. Industry has objected, stating that the agency should work through professional groups who routinely publish such guidelines. As of mid-1982 the matter was still unresolved. The OSHA position on a worker's "right to know" is the object of much controversy at this time. A Hazardous Materials Identification System (HMIS) labeling proposal in being implemented to promote worker safety when using chemical raw materials. The use of Material Safety Data Sheets (MSDS) is still voluntary, except for the U.S. Coast Guard and a few other small areas, but it will probably be mandated ultimately by either OSHA or EPA (TSCA). Under Section 6(b)(7) OSHA is now attempting to provide workers with vast files of data relative to the identification of chemical ingredients in industrial mixtures, even though they might constitute confidential information of extreme importance to the business interests of the suppliers involved. The agency feels that confidentialities, trade secrets, patient/doctor communications and records are all subsidiary to the basic health and safety of the worker and should be accessible. In the near future they may follow up this presumed role more closely and agree with the EPA to leave chemical hazard warnings up to TSCA. Provisions of the "right to know" issue that are contested by industry include the right of workers to walk off the job if they feel that hazard information is not provided or is inadequate, responsibility of the employer to provide lists of hazardous substances that are being used, requirements for the employer to maintain safety records over long periods of time, and the publication of trade secret information. There is some concern that tanks and filling machines will perhaps have to be placarded with hazardous product data on contained products, although pipelines, pumps and so forth would be exempted. Under their proposed new Hazard Communication Rule, OSHA plans to phase in these standards by 1985. A hazardous mixture is also defined as any combination of chemicals containing at least 1 % of a hazardous chemical. On this basis, even a shaving cream could be cited as hazardous. The "right to know" proposed standard could pose an initial cost of $590 million, with annual costs of $230 million thereafter, in 1982 dollars. It is regarded as the most important regulatory action to affect the aerosol industry in 1982 and 1983. Department of Transportation (DOT) This relatively new federal unit operates under Title 49 of the Code of Federal Regulations, having replaced the older Interstate Commerce Commission (ICC) as the regulatory body dealing with interstate transportation. In the regulations, virtually all aerosols are covered under Section 173.500(a)(4) of the Official Tariff. They are considered as ORM-D commodities: materials that present a limited hazard during transportation, due to their form, quantity or packaging. These materials must be subject to the exemptions recited in Section 172.101. A specific shipping description is required, as provided in Section 172.101. Those regulations specific to aerosols are listed in Sections 173.300(a) definitions of compressed gas, 173.300(b) definitions of flammable compressed gas, 173.306(a) requirements for limited quantities of (nonflammable and flammable) compressed gases and 173.1200(8) requirements for (non-flammable and flammable) compressed gases. Definitions are presented in the Aerosol Flammability chapter. Most aerosol shipments are covered under 173.306(a), and these requirements are given as follows: Limited quantities of compressed gases, (a) Limited quantities of compressed gases for which exceptions are permitted as noted by reference to this section in $172,101 of this subchapter are exception, specification packaging requirements of this subchapter when packed in accordance with the following paragraphs. In addition, shipments are not subject to Subpart F of Part 172 of this subchapter, to Part 174 of this subchapter except $174.24 and to Part 177 of this subchapter except $177,817. (1) When in containers of not more than 4 fluid ounces capacity (7.22 cubic inches or less) except cigarette lighters. Special exceptions for shipment of certain compressed gases in the ORM-D class are provided in Subpart N of this part. (2) When in metal containers filled with a material that is not classed as a hazardous material to not more than 90 per cent
538 The Aerosol Handbook of capacity at 70°F then charged with nonflammable, non- liquefied gas. Each container must be tested to three times the pressure at 70°F and when refilled, be retested to three times the pressure of the gas at 70°F. Also, one of the following conditions must be met: (i) Container is not over 1 quart capacity and charged to not more than 170 psig at 70°F and must be packed in strong outside packaging, or (ii) Container is not over 30 gallons capacity and charged to not more than 75 psig at 70°F (3) When in metal container charged with a solution of materials and compressed gas or gases which is non- poisonous, provided all of the following conditions are met. Special exceptions for shipment of aerosols in the ORM-D class are provided in Subpart N of this part. (i) Capacity must not exceed 50 cubic inches (27.7 fluid ounces). (ii) Pressure in the container must not exceed 180 psig at 130°F. If the pressure exceeds 140 psig at 140°F but does not exceed 160 psig at 130°F, a specification DOT 2P ($178.33 of this subchapter) inside metal container must be used; if the pressure exceeds 160 psig at 130°F, a specification DOT 2Q, ($178.33a of this subchapter) inside metal container must be used. In any event, the metal container must be capable of withstanding without bursting a pressure of one and one-half times the equilibrium pressure of the content at 130°F. (iii) Liquid content of the material and gas must not completely fill the container at 130°F. (iv) The container mnst be packed in strong outside packagings. (v) Each completed container filled for shipment must have been heated until the pressure in the container is equivalent to the equilibrium pressure of the content at 130°F. (55°C.) without evidence of leakage, distortion, or other defect. (vi) Each outside packaging must be marked INSIDE CONTAINERS COMPLY WITH PRESCRIBED REGULATIONS. The Section 173.1200 requirements are provided in the introductory statements and then specifically in 173.1200(8). These are provided as follows: If the material meets the definition of an ORM-D then the material may be transported using the proper shipping name: Consumer Commodity. The material may be hazard classed as an ORM-D material provided that an ORM-D exception is authorized in the Hazardous Materials Table of Section 172.101, and that it is prepared in accordance with the following: (The gross weight of each package must not exceed 65 pounds and each package offered for transportation aboard aircraft must meet the requirements of Section 173.6) (Paragraphs 1 through 7 are omitted as inapplicable.) (8) Compressed gases must be: (i) In inside containers, each having a water capacity of 4-fluid ounces or less (7.22 cubic inches or less), packed in strong outside packagings. (ii) In inside metal container charged with a solution of materials and compressed gas or gases which is non- poisonous, meeting all of the following: (A) Capacity may not exceed 50 cubic inches (27.7 fluid ounces). (B) Pressure in the container may not exceed 180 psig at 130°F (55°C) but does not exceed 160 psig at 130°F (55°C) a specification DOT 2P ($178.33 of this subchapter) inside metal container must be used; if the pressure exceeds 160 psig at 130°F (55°C), a specification DOT 2Q (5178.33a of this subchapter) inside metal container must be used. In any event the metal container must be capable of withstanding, without bursting, a pressure of one and one-half times the equilibrium pressure of the contents at 130°F (55°C); (C) Liquid content of the material and gas not completely fill the container at 130°F (55°C); (D) The containers must be packed in strong outside packagings; and (E) Each completed container filled for shipment must have been heated until the pressure in the container is equivalent to the equilibrium pressure of the content at 130°F (55°C) without evidence of leakage, distortion, or other defect. (iii) In a non-refillable inside metal container of 50 cubic-inch capacity or less (27.7 fluid ounces), with foodstuffs or soaps and with soluble or emulsified compressed gas, provided the pressure in the container does not exceed 140 psig at 130°F (55°C). The metal container must be capable of withstanding, without bursting, a pressure of one and one-half times the equilibrium pressure of the contents at 130°F (55°C) and must comply with the following provisions: (A) Containers must be packed in strong outside packagings, and (B) Liquid content of the material and gas may not completely fill the container at 130°F (55°C). (iv) In refillable inside metal containers with cream and soluble or emulsified compressed gas packed in strong outside packagings. Containers must be of such design that they will hold pressure without permanent deformation up to 375 psig and must be equipped with a device so as to release pressure without bursting of the container or dangerous projection of the parts at higher pressures, (v) In non-refillable inside metal containers charged with a solution, containing biological products or a medical preparation which could be deteriorated by heat, and compressed gas or gasses which is non- poisonous and non-flammable. The capacity of each container may not exceed 35 cubic inches (19.3 fluid ounces). The pressure of the container may not exceed 140 psig at 130°F (55°C) and the liquid content of the product and gas may not completely fill the container at 130°F (55°C). One completed container out of each lot of 500 or less, filled for shipment, must be heated, until the pressure in the container is equivalent to the equilibrium pressure of the content at 130°F (55°C). There may not be any evidence of leakage, distortion, or other defect. Container must be packed in strong outside packagings. (vi) In electronic tubes, each having a volume of not
Government Regulations 539 more than 30 cubic inches and charged with gas to a pressure of not more than 35 psig and packed in strong outside packagings. (vii) In an inside metal container as a component of an audible fire alarm system powered by a compressed gas meeting the following provisions: (A) Each inside container must have contents which are not flammable, poisonous or corrosive and defined under this Part; (B) Each inside container may not have a capacity exceeding 35 cubic inches (19.3 fluid ounces); (C) Each inside container may not have a pressure exceeding 70 psig at 70°F (21°C) and the liquid portion of the gas may not completely fill the inside container at 130°F (55°C); (D) Each inside container must be designed and fabricated with a burst pressure of not less than five times its charged pressure or more than the pressure of the content at 130°F (55°C); and (E) Each fire alarm system must be packed in a strong outside packaging. At the present time (1982), the only DOT-approved '' strong outside packaging'' for aerosol units is 175 lb or heavier weight corrugate, depending upon package weight, unless one considers wood or nietal containers. In Europe it is now commonplace to find aerosols six- packed in light plastic trays and PE shrink-wrapped. In the U.S.A. this substantially less expensive wrap is not permitted, and several well-documented petitions based upon extensive tests have been rejected. One minor consolation is that, in a warehouse fire, corrugate cases were found to be highly beneficial as heat insulators, acting to slow down dramatically the bursting and possible fire-balling of aerosol cans. Shrink-wrapped palletloads did not demonstrate this effect. Despite the much lower BTU (cal/g) rating of the shrink-wrap, fires involving it were much more intense and harder to control. In summary, the industry has very few problems with the DOT at the present time. A good, reasonable relationship has been established, and is likely to continue for a number of years to come. The U.S. Department of Agriculture (USDA) Until about 1970 the USDA administered the FIFRA and other acts important to the aerosol industry, but at that time they were transferred to the newly created EPA and the Department took a subsidiary role. However, marketers have found that USDA must authorize the use of various products within "official establishment' ' operating under the Federal meat, poultry, shell egg grading and egg products inspection programs. Depending upon their composition, products may be approved by the USDA for use in non-edible product processing areas, non-processing areas and/or exterior areas of these establishments, or actually within such areas, provided they do not come into direct contact with food products. A number of restrictions apply. For pesticides, in addition to EPA registrational requirements, the product must have precautionary labeling and use directions relating to such processing plants. In general, no product may be used which masks odors resulting from insanitary conditions, or which emits an odor that can penetrate into an edible product area. A stainless steel cleaner, for example, should be formulated with an absolute minimum of fragrance if USDA "exterior" approval is desired. In pesticides areas the USDA wait for EPA approval, after which they will then provide separate approval. It is best to work simultaneously with both regulating bodies when attempting to obtain both EPA and USDA registrations for a given product, showing each the correspondence received from the other. After registration by the USDA, any distributor proposing to sell the product to official establishments must submit a completed MP Form 28 to the USDA for that specific item. A letter of authorization is then issued. If the registrant is not the distributor, a copy of the letter is issued to the registrant as well, but no formal authorization is issued to a non-distributor. Correspondence with the USDA on these matters should be directed to: Chemist-In-Charge Compounds Evaluation Unit, CPS Product Safety Branch Food Ingredient Assessment Division Food Safety and Quality Service Science Division U.S. Department of Agriculture Building 306, Bare. East Beltsville, MD 20705 An estimated 5 to 12 million aerosols per year are registered with the USDA. Many are industrial products designed for use in restaurants, food kitchens, meat processing plants and poultry house. A significant number are packaged in large monobloc aluminum cans with paper labels. State Regulations Under the constitutional scheme, in the U.S.A. those powers not specifically ceded to the Federal Government by the states are retained by the states and
540 The Aerosol Handbook may be exercised through the use of'' police powers'' or local state authority on all matters which concern the health and welfare of the citizens of the state, or the state itself. During the 1970s and especially during the opening years of the 1980s (under Reagan) the states have greatly increased their activity—especially in areas of consumer protection and environmental matters. Both have a profound effect upon the aerosol industry. Usually, state regulations are designed to dove-tail with and further support federal regulations in the same area. But often some states will attempt to do more, citing special problems of their cities, such as clean air control in the Los Angeles basin, or storage in congested New York City warehouses. In such cases, industry must adapt to new "local" regulations that further complicate the business process. Some U.S.A. communities have large new settlements of immigrants, who cannot read English labels and who may therefore use pesticides or other products they purchase incorrectly. More than one marketer has been penalized for selling an English-labeled product in communities with a high percentage of non-English speaking people. The deliberate inhalation of toluene-containing aerosols (such as paints and coatings) has become a major regional social problem in the southwest. An example of local legislation to counter this situation is the California Legislature amendment to Section 380 of the Penal Code passed as Assembly Bill 797 in March 1980. This amendment prohibits retailers from selling products containing toluene or any other item or combination of hydrocarbons capable of inducing toxication to minors. Penalties extended from $2500 fines to six- month jail terms and even loss of license. In the background of this legislature was a fast growing problem of substantive inhalent abuse, with no easy solutions. In one city, aerosol drug abuse increased 40 times from 1974 to 1979. In addition to the obvious commercial and legal problems resulting from aerosol drug abuse, the personal and community injury is substantial. Irreversible damage to the central nervous system of the abuser may occur after the first or second year of "sniffing". Brain and liver damage may also result. These symptoms would indicate that toluene and the xylenes are more insidious than heroin when misused in this manner (heroin does not attack the nervous system.) Any such abuse is a strain on the community. An increase in violent crime seems to occur along with such drug abuse problems. The physical care of the "victims" adds further to strains on their families and the community. The original version of California AB-797 would simply have banned the sale of any toluene type product in California, except gasoline. Similar legislation was considered in Texas, as a consequence of serious abuse cases in Houston, Austin and Corpus Christi, but was reduced to a ban on sale to persons under 18 years of age. Most aerosols used for "sniffing" are said to have been stolen, so such partial bans are of doubtful utility. To help in this situation industry has contributed funds for model educational programs and other worthwhile activities, but the problem still remains a serious one for the paints and coatings segment of the aerosol industry. Regulations Concerning Weights and Measures. Regulatory powers over weights and measures of commodities are enjoyed by both the Federal Government and the several states. Federal activities are handled by the Bureau of Weights and Measures, National Bureau of Standards, Office of Productivity, Technology and Innovation of the U.S. Department of Commerce in Washingtion, D.C. One of the main objectives of the Bureau is to coordinate and standardize state regulations covering weights and measures in the interest of uniformity and improved interstate commerce. Many of these activities are finalized each year at the National Conference on Weights and Measures. Attendees at these gatherings are mostly state officials with direct responsibilities in this area. After agreements are reached, sometimes by conference approval of suggested model laws, these officials return and generally take actions necessary to bring their states into compliance. The NBS became interested in aerosols about 1963, at a time when they were actively promoting the concept that certain packages, such as aerosols and fire extinguishers, were basically "devices" and as such, must deliver the declared contents, rather than just contain a stated quantity. Until then, the aerosol industry had always operated on a "contained" or dry-tare quantity basis. Shortly afterward, they changed to a "delivered" or wet-tare basis. The method to determine quickly the delivered weight became rather important. The ideal method was to dispense as much as the consumer did over a period of weeks or even months. Originally, and up to about 1981 there were four methods, one for foods, one for high-viscosity products, one for non-food foam pro-
Government Regulations 541 ducts and finally one for low-viscosity products. Various test allowances were stipulated, since it was thought that the quick test method left slighdy more in the can than a consumer would. In the case of low- viscosity products the allowance was set at Vi6-oz (1.8 g) for packages containing \Vz oz to 3 oz (42.5 to 85.0 g) and at Va oz. (3.5 g) for all larger sizes. About 1967, industry discovered that test allowances were not really needed, and they were rarely used after that. This information and data was presented to the NBS, but they failed to act on it until about 13 years later, when some Pennsylvania weights and measures officials examined a huge number of aerosol products and discovered the same facts, with the possible exception of a small variation for foams. Consequently the Model Law and methods of test were changed. The procedure involves selecting the lightest gross weight dispenser from at least ten like containers, without overcaps. The unit is shaken as specified on the label. Holding the container, as per label instruction, it is then actuated until commercially empty of liquid and gas, with the operator recording the weight of the emptied unit and determining the wet tare net weight accordingly. If the net weight equals or exceeds the declared weight, then the NBS suggest "it may be reasonable to assume that the lot is satisfactory." If the net weight is less than the declared weight, it is necessary to treat the ten packages as a sample of the lot. They may all be tested as was done for the lightest can, but a more rapid and approved procedure is to go through the test only for the heaviest gross weight package. The wet tare weights of the lightest and heaviest units are averaged to obtain the average wet tare. This weight can then be subtracted from the gross weights of all ten cans to determine the wet tare net weight of each to the nearest Vi6 oz (1.8 g). (Note: Actually, most balances available to officials are accurate to at least 0.1 g.) Errors that are "unreasonably" large are circled. For aerosol packages in the range of 2 to 8 oz (56.7 to 226.8 g) an unreasonble error is outside the range of-3/i6 to +% oz (-5.3 to + 10.6 g) from the declared weight. For aerosols containing 8 to 32 oz (226.8 to 907.0 g) an unreasonable error is outside the range of- lA to + Yz oz (-7.1 to + 14.2 g) from the declared weight. (Reference: NBS Handbook No. 67 & 130, Section 5.1.3 Step 3.) If one unit in the ten has an unreasonably large negative error, the inspector may elect to examine more units, order the lot repackaged or relabeled, or hold it in violation of the statute and taken in evidence, at his discretion. If two units in ten have an unreasonably large negative error the entire lot must be held in violation, without looking at any further packages. Large plus errors are merely reported to the store operator by inspectors. Several viscous aerosol products may leave as much as 1 Vz oz (42.5 g) in the can when commercially emptied. They are commonly filled by at least this much extra in order to meet wet tare declared weight requirements. Most non-viscous products will only leave 1 to 2 g in the cans when commercially emptied, even in the case of large package sizes. European Regulations This area can be approached best from a consideration of the European Economic Community Directives, plus those of various other multi-national organizations. Net Contents The EEC Directives require that aerosols must be marked with a statement of quantity, declared in volume terms using the metric system. The declared volume is corrected to a reference temperature of 68°F (20°C). Minimum type sizes are stipulated. For volumes to 50 ml the declaration must be 2 mm high, for 50 to 200 ml it must be 3 mm high and for 200 to the maximum fill of 750 ml it must be 4 mm high. In the EEC Prescribed Quantities Directive, thirteen volume fills are stipulated for metal containers, ranging from 25 to 750 ml. Six volumetric fills are prescribed for glass and plastic containers, and these range from 25 to 150 ml. Fills below 25 ml are not subject to the Directive. In every instance the capacity of die container itself must also be shown on the label, but in such a way that consumers will not confuse it with the quantity declaration. The metal containers normally have capacities about 20 to 25% greater than the volume of their contents. Additional information in this complex area can be obtained in the chapter on Metal Aerosol Containers, in the Code of Practice of the British Aerosol Manufacturer's Association (BAMA), Fourth Edition, 1980, available at 9 pounds-sterling by applying to them at the Alembic House, 93 Albert Embankment, London SE1.7TU, or from the EEC Directive itself. In order to indicate compliance with the EEC Prepackaging Directive and other EEC rules, an epsilon or "e" must be shown in the same field of vision as the quantity declaration, with a height of at least 3 mm.
542 The Aerosol Handbook The form of the "e" is specifically defined (see Aerosol Flammability chapter). In the absence of this qualifying sign the finished product will be immediately subject to the labeling requirements of the country where it is offered for sale. If these are different from those of the EEC, it is likely that product seizure or other sanctions will be applied. EEC Directive No. 75/324 restricts aerosol container sizes to 1000 ml for metal, 220 ml for protected glass and 150 ml for plain glass. Plastic containers are classed with either protected glass or plain glass, depending on whether they shatter or not when impacted. The degree of filling is defined as a minimum of 75v% at 68°F (20°C) and a maximum of 90v% at 122°F (50°C), for all products with container capacities greater than 50 ml. The EEC directives do not discuss limit temperatures for the liquid-filling of aerosols, but the West German Technical Regulations for Pressurized Gases (TRG - New Version) specifies that this shall not occur below 158°F (70°C) and other national regulations cover this aspect as well. Transportation In Europe, both national and international organizations legislate the transportation by road, railroad, sea and air. There is a high degree of regulatory harmony between these rule-making bodies, as might be anticipated. EEC regulations and UN recommendations are consistant with these transport regulations. The Accord Europeen Relatif le Transport International Dangereuses par Route (ADR) controls international road transportation in Europe. Aerosols (officially called pressurized packages) are grouped into the "Danger Class 2", and further differentiations are made according to (a) non-flammability, (b) flammability, with less than 45% flammable materials, and (c) flammability, with more than 45% flammable materials. Note that a "flammable material" for these purposes is a substance with a Tag Closed Cup Flashpoint of 212°F (100°C), although different flashpoint testers are usually used. Units with over 45% flammable content must be marked with the word "Aerosol" plus a symbol showing a black flame on a red background. Other aerosols must be simply identified with the word "Aerosol" on the outer packings. All transport papers muist be filled out carefully. The propellent used must be entered specifically with a red underline, together with the class, number and letter of the ADR specification. For example, if an aerosol contains more than 45 % flammables and propane/butane is the propellent, the identification needs to be, "Pressurized packages with propane/butane, Class 2, Number 10b, 2". The Reglement International Concernant le Transport de Merchandise Dangereuses par Chemin de Fer (RID) controls the international railroad transportation in Europe. The grouping of dangerous goods categories is very similar to that described for the ADR. The definition and classification of aerosols is identical, as is the numbering system, but RID uses only the last three digits of the ADR numbers. All types of aerosols can be transported by express. The International Maritime Dangerous Goods Code (IMDG), formerly IMCO covers the shipment by sea of aerosols of more than 50 ml content. The grouping of aerosols according to the regulations in Annex "A", also called the IMCO code, is much more complicated than in the ADR or RID regulations. Depending upon the container content, aerosols can be grouped very differently: Not dangereous: Aerosols containing no flammable gases and not more than 10% of flammable liquids. Class 9: Aerosols containing no flammable gases but more than 10% flammable liquids. Class 2: Aerosols containing more than 10 % of flammable gases. Class 3: Aerosols containing either more than 45 % of flammable liquids and no flammable gases — or — more than 35% flammable liquid in the presence of flammable gases. The class grouping, with UN-number and page number of the IMCO Code defines the necessary kind of packaging, declaration and marking, weight of transport unit and the location on board the freight-carrying ship. The prescribed warning signs are similar to those in use by the ADR and RID, but the flame symbol carries the wording "Inflammable Gas" and also the number of the Danger Class. The International Air Transportation Association (IATA) control worldwide shipments of aerosols by air, subject to many additional restrictions by the individual carriers themselves. Aerosols are listed in the alphabetical article compilation under numbers 2164-2166. The
Government Regulations 543 compilation describes the official transport description of the goods, the classification, the prescribed danger symbol and the permission for transport by passenger or freight planes. The I ATA warning specifications are different than those discussed under ADR, RID, and IMDG. If aerosols contain flammable gases or liquids the transport unit must carry a prescribed red flame symbol (red label) with a specific warning statement on it. Otherwise a green label is required, with the imprint, "Non-flammable compressed gas. Keep cool." German national regulation TRG-300 is very complete and has served as an unofficial European standard for countries not having developed their own internal regulations. The EEC may adapt parts of it in time. The regulation differentiates between warehouse rooms, storage rooms and sales rooms. Warehouse rooms are divided up into Size I (up to 646 ft2 or 60 m2), Size II (to 5,380 ft2 or 500 m2) and Size III (above 5,380 ft2 or 500 m2). Only 60% of these spaces must be used for actual storage. Each room must be equipped with adequate fire extinguishing pipelines and devices, and the fire protection system has to be coordinated with the local fire department. No warehouse room may be located in a building used also for residential purposes. Rooms of Size II must not be below any other rooms continuously occupied by people. Rooms of Size III must only be in buildings used exclusively for warehousing. Each room must have fire resistant walls, ceilings and floor material, and be equipped with two separate exits with fire-retardant doors. The rooms must not have any heating devices with open fire and no chimney closures for cleaning. Storage rooms are rooms not larger than 215 ft2 (20 m2) where aerosol packages may be kept before they are moved to the sales rooms, and sales rooms must not be used to store more product than is presumably required for one day. Filled aerosols must not be permitted in store windows, and aerosol sales stands are not permitted near store exists. They must not be stored in passages, stairway rooms, hallways or directly under roofs. All warehouses must be adequately ventilated and provide for easy escape in case of danger. Smoking or open fire is not permitted in any storage room containing aerosols, and such rooms must not contain wastes or other flammable materials that are easily ignited. The rooms must show the required warning signs. The European regulations are sometimes rather mind-boggling in their complexity. For example, in Germany the transport of dangerous goods is covered by two international recommendations, five international regulations and three national regulations, totalling over 4000 pages of printed text. The portions valid for aerosols are sprinkled throughout these compendia and must be ferreted out for any real understanding of their portent. Regulations Outside the U.S.A. and Europe In Canada, new multi-model regulations are under development covering all kinds of transport. Previously the "Red Book" regulations for rail were seen as highly effective and had been in use for many years. National sea and air regulations were similar. No federal regulations were applied to highway transportation, since this was classed as a provincial responsibility. These are now all replaced with the new Transportation of Dangerous Goods Act of 1980 and equivalent provincial acts developed in 1981 and 1982. Regulations under the basic act are still in development (mid-1982) and are being published piecemeal in The Canada Gazette as Transportation Canada's Dangerous Goods Branch Codes 1,2,3,4 and so forth, still in draft form. Industry sees these as giving them an unconscionable economic burden. Infractions carry penalties of up to $100,000 or two years in prison. Specific problems are that there will be an unnecessary degree of container obsolescence due to mandated discard of low lifespan tankcars, drums and so forth. The laws will demand Canadian labeling, even in aerosols sent down to Canada's largest customer: the U.S.A. The proposed regulations would discard proven IATA regulations in favor of unproven UN ideas. Added definitions are needed. A total of nine classes are being developed for dangerous goods. During 1969, a tough Canadian Hazardous Products Act was enacted and went into effect on February 28, 1972 because of the difficulties experienced by industry in complying with some of the more onerous provisions. The act is fairly complex. It mandates a series of twelve bold danger, warning and caution symbols for product labeling, in accordance with the degree of hazard and also requires bilingual (English and French) label warnings for many household products. Consumer commodities covered under the regulation include bleaches, polishes, sanitizers, glues, aerosols and cleaners. Every type of aerosol is required to carry an explosive warning symbol, unless it can be rendered
544 The Aerosol Handbook non-explosive by means of RVR or PRM can dome, a special pressure-relieving valve or some other authorized fitment. At the time the law went into effect, Minister Ronald Bashford, head of Canada's Consumer and Corporate Affairs, indicated that the octagon around an exploding bomb signifies "DANGER —Explosive—it can kill you." A diamond around the bomb would mean "WARNING—Explosive—it can severely injure you." And a triangle shape would mean "CAUTION — Explosive — it can injure you." A typical aerosol furniture polish, sold in Canada, would carry three symbols: "DANGER—Poison—WARNING — Flammable — CAUTION — Explosive. The twelve symbols and their significance are illustrated in Figure 1. They are required for all regulated products and are placed on the principal display panel below the common name or brand name of the product. The area of a circle circumscribing the symbol may not be less than 4% of the area of the principal disply panel and, in no event, can it be less than V8 " in diameter. Despite their approximate size equivalency, the danger symbol is most prominent, followed by the warning sign and then the caution symbol. The signal word, at least V32" in height, is inscribed just below the symbol. The statement of primary hazard is inscribed just below the signal word, and in a height of 716" for smaller cans and '/a" for the larger sizes. Statements of the nature of a secondary hazard, statements of precaution, first-aid treatment and so forth are presented anywhere on the label in type not Figure 1. DANGER/POISON DANGER, FLAMMABLE DANGER/EXPLOSIVE DANGER/CORROSIVE WARNING/POISON WARNING/FLAMMABLE WARNING/EXPLOSIVE WARNINGCORROSIVE CAUTION/POISON CAUTION/FLAMMABLE CAUTION/EXPLOSIVE CAUTION/CORROSIVE less than Vi6 " high for all aerosol can sizes, except the 300 x 709 cans, where they are Va" high. Flammable products are judged as to relative hazard by means of flashpoint, but it now appears, because of industry protests, the aerosols will be assessed according to the general concepts for "Extremely Flammable", "Flammable" and "Combustible" classification as used in the United States FHSL Act. The government may also cause the manufacturer of any product to disclose the complete formulation in order to ensure adequate regulations. The appearance of one, two or three prominent symbols in the middle of the front panel of Canadian aerosols and other regulated products is quite disastrous from an aesthetic standpoint. It will undoubtedly result in more expensive and often less effective products as marketers attempt to avoid this stigma. The Canadian Consumer Packaging and Labeling Act of 1972 became effective in 1973 and was patterned after the U.S. Fair Packaging and Labeling Act (FPLA). However, it has a considerably tougher make up. Like the CHPA, it is administered by the Canadian Department of Corporate and Consumer Affairs. It has a number of important features. Some are recited as follows: a. Covers all household products and is intended to facilitate rational choice of products by consumers at the point of purchase. b. The net weight must appear in both the appropriate English units (pounds, etc.) and in the equivalent metric units. (This continues Canada's move toward total metrication.) c. Bilingual labeling is specified for all but a few exempted products. d. A provision encourages voluntary package-size standardization by industry, but empowers the government to seize products if it determines that there are too many sizes and shapes. e. Gives the government the power to issue ' 'on the spot" regulations, justifying them on the grounds that they are beneficial to consumer. The net effect of these and other legislated restrictions have led industry observers to suggest that the Canadian aerosol industry will have a significantly tougher time coping with the regulatory burden than will be the case for the industry in the U.S.A., at least for the foreseeable future. (Brief comments for registration in other countries are listed on Page 484)
545 BUYER-SELLER RELATIONSHIPS 16 Many Marketers purchase from contract fillers finished aerosol products which are developed in the laboratory of the filler. These are normally tested for effectiveness and safety, but to varying extents. The larger contract packagers, with more extensive facilities and more money available for outside clinical testing can often provide a product superior to that of the smaller filler. An exception to this is encountered where the smaller firm has developed a high level of expertise in one or more specific product categories. The marketer will often conduct his own efficacy and safety tests upon products received from contract fillers. But in some cases such testing may be very cursory indeed. One document that is now becoming of increasing importance is the'' Product Safety Warranty''. The supplier must then set forth specific information, as illu- strated in this example: PRODUCT SAFETY WARRANTY Date Return to Mr. John A. Doe, Buyer True Blue Corporation. Name of Aerosol Product: General Chemical Composition: Any Required Health and Safety Recommendations: Remarks: Answer the following: Is this aerosol toxic to persons who use it incorrectly? Yes No If "Yes Explain
546 The Aerosol Handbook Is this aerosol an irritant to the eyes? Yes No Skin? Yes No The respiratory system? Yes No If 'Yes"explain Does the product contain materials in any of these categories: Metallic compounds of aluminum arsenic, lithium, lead, mercury, copper, phosphorus or silver? Yes (Which ) No Aromatic carbon compounds, as benzene, toluene, xylenes, tetralin, methylated naphthalenes, aniline, phenol or kerosenes? Yes No Aliphatic carbon compounds, as formaldehyde, methanol, ethylene glycol, chloroform, carbon tetrachloride, diethyl ether or acetone? Yes No Inorganic compounds, such as free sodium hydroxide, free potassium hydroxide, fluorides, chromate, cyanide or meta-silicates? Yes No List materials, except metallic compounds, (if any, and state the approximate quantity present. Flammability situation: Flame Propagation at 70°F (full valve opening): inches. Flame Flashback at 70°F (any valve opening): inches. Closed Drum Test at 70°F seconds. Modified Open Cup Test °F Percent '' Flammables'' wt % (Those which have flashpoints below 212°F) Pressure at 70°F: psig. At 130°F: psig. (Using production crimp.) Delivery Rate at 70°F: gm/sec Level of vacuum crimp (if any) " Hg°. Certified by: Title: Company: Some of these Product Safety Warranties call for attachment of any container compatibility warranties, reports of clinical testing and other documents that may be available to further indicate the safety of the product. When the buyer is ready to place an order for aerosols, he normally protects his interest under the provisions of the Fair Labor Standards Act by setting forth a statement of terms and conditions on his purchase orders. A typical format would be as follows: Front Side Seller agrees he has full knowledge of the conditions printed on the reverse side hereof; and the same are part of the agreement between Buyer and Seller and shall be binding notwithstanding any terms or conditions which may be contained in any acknowledgement, invoices or other form seller may submit. Reverse Side 1. COMPLETE AGREEMENT. This order is the complete agreement between Buyer and Seller. It supercedes all agreements, understandings, and writings made prior to the date of this order. Subsequent changes to this order must be in written form, signed by the Buyer's authorized representative, and delivered to the Seller. 2. CHANGES TO THIS ORDER. Seller agrees to perform any changes to the work or services being furnished under this order when requested by the Buyer in writing. If the changes made by the Buyer results in a variance from the Seller's cost performance or deliveries, an equitable adjustment of the order will be negotiated and incorporated into the order. Seller must notify Buyer in writing if an adjustment is required. Pending such adjustment, Seller will proceed to perform under this order as revised. 3. DISCOUNTS. Discounts will be computed from the date of receipt of invoice or the date of receipt of the goods or services ordered, whichever is later. If original invoice or shipment is incorrect, discount will be computed from date of correction. 4. DELIVERY. Each package shall be numbered and labeled with the Buyer's order number,
Buyer-Seller Relationships 547 stock number, contents and weight, shall contain an itemized packing slip and shall be properly packed for shipment. No charges will be allowed for packing, crating, freight, express or cartage unless specified on the face hereof. Time is of the essence hereof and if any goods are not delivered within the time specified on this purchase order, or within a reasonable time if no time is specified, Buyer may refuse to accept such goods and may cancel this agreement. 5. PRICE. In case the price specified herein includes the payment or allowance of any trans- portion charges by Seller, Buyer shall be charged with any increase or credited with any decrease in such transportation in effect at the date hereof. When no unit price is stated on the face of this purchase order, this order must not be filled at higher prices than last quoted to the Buyer. 6. QUANTITY. Goods delivered in excess of order may be returned at Seller's expense. 7. TAXES. The prices on this order include all applicable state, local, and federal taxes in effect on the date of this order. Seller will comply with all applicable tax laws and will indemnify Buyer against loss due to non-compliance on Seller's part. 8. WARRANTIES. The Seller unconditionally warrants that the items furnished under this order conform to the specifications, drawings, samples, or other wirtten or physical descriptions or guides referenced in this order, and that the items furnished under this order: a. Will be in accordance with the terms of this order. b. Are free of liens and other encumbrances. c. Are free from defects in labor, materials and workmanship. d. Seller has good and marketable title to the items furnished. Buyer reserves the right to cancel unfilled portion of order, without liability, for breach of warranty, and return for full credit, at Seller's expense, any materials not conforming thereto. 9. INSPECTION. Final inspection and acceptance of the items furnished will be accomplished by the Buyer within ninety (90) days after delivery. Such inspection will be conclusive except, for latent defects or fraud. The Seller agrees to allow Buyer, on request, free access to his plant and operations for the purpose of inspection. Payment for material prior to inspection does not constitute an acceptance. 10. PATENT INDEMNITY. Seller will indemnify Buyer (and all persons claiming under Buyer) all claims or liabilities for actual or alleged infringements of any patent, trademark, copyright or other similar rights in connection with the materials or articles furnished under this order, except where such claims and liabilities result from the Seller's strict compliance with Buyer's drawings, designs, specifications or written instructions. 11. DRAWINGS, ETC. All drawings, blue prints, dies, patterns, tools, printing plates, etc. prepared or constructed by the Seller and paid for by the Buyer shall be the property of the Buyer, and upon completion of deliveries hereunder, or upon termination of this agreement, shall be delivered to Buyer. 12. DEFAULTS. Buyer may, by written notice to Seller, cancel for default this order in whole or, from time to time, in part, if: a. The Seller fails to deliver the material or perform the services ordered with the time specified. b. The Seller fails to deliver materials which conform to the requirements of this order or to perform any of the provisions of this order or so fails to make progress as to endanger performance of this order in accordance with its terms. c. The Seller becomes insolvent or commits an act of bankruptcy. Delays, defaults or stoppages due to acts of God or other causes beyond the control of Buyer or Seller will not result in liability to either party. In the event that Buyer elects to cancel this order in the whole or in part solely for the convenience of the Buyer, an equitable adjustment in the price of this order will be negotiated.
548 The Aerosol Handbook 13. ASSIGNMENTS. Seller may not assign any monies due or to become due under this order without the written consent of the Buyer. Any such assignment as may be authorized by Buyer will be subject to setoff, recoupment or other lawful means of enforcing any present or future claims which Buyer may have against Seller. Seller may not assign his obligation to perform under this order. 14. COMPLIANCE WITH STATUTES AND REGULATIONS. All work performed under this order will be in accordance with all applicable state, local, and federal statutes and regulations. Seller assumes full responsibility for noncompliance on his part with any such laws and regulations. Such statutes shall include, but not be limited to, the Fair Labor Standards Act of 1938, as amended and the regulations and orders of the U.S. of Labor issued under Sect. 14 thereof. 15. CONFIDENTIAL RELATIONSHIP. Seller agrees to treat as strictly secret and confidential all specifications, drawings, blueprints, nonmen- clature, samples and models and other information supplied by Buyer. Unless writt'en consent of Buyer is first obtained, Seller shall not in any manner advertise, publish, or release for publication, any statement mentioning Buyer or the fact that Seller furnished or contracted to furnish Buyer items required by this contract. Seller shall not disclose any information relating to this contract to any person not entitled to receive it. Buyer's blueprints, instructions and facilities, tools and materials (as defined in pph. 8 and 11) shall be used exclusively in the production of items required by this contract for Buyer, and shall not be used for production, manufacture or design of any item for any other firm, person, or corporation, without Buyers's written consent. 16. CONFLICT OF INTERESTS. If any of the provisions of Seller's proposal or Seller's other writing are in conflict with the terms of this purchase order, the terms of this purchase order shall govern. 17. RIGHTS AND REMEDIES. The Buyer, in addition to any rights and remedies it may have at law or in equity or under any other provision herein, shall also have the right to any one or more of the following cumulative remedies. a. In the event Seller fails to provide the supplies in accordance with the requirements hereof, Seller, upon request by Buyer agrees to promptly at his own expense, correct, replace or repair, in any manner satisfactory to the Buyer, any supplies found nonconforming or defective and rejected by the Buyer. b. In the event Seller fails to correct, replace or repair any non-conforming, defective or rejected supplies in a manner satisfactory to the Buyer, Buyer may do so at Seller's expense. 18. WAIVER. No waiver of a breach of any provision of this order shall constitute a waiver of any other breach or provision. 19. LAW GOVERNING. This order is to be governed by and construed in accordance with the laws of the state from which this order is issued. The seller will generally respond in kind, in order to protect his interests when submitting invoices and similar documents relating to work planned or accomplished. A typical format would be as follows: Front Side Buyer agrees he has full knowledge of the conditions printed on the reverse side hereof; and the same are part of the agreement between Buyer and Seller and shall be binding notwithstanding any terms or conditions which shall be contained in any acknowledgement, invoices or other form Buyer may submit. Reverse Side 1. COMPLIANCE WITH STATUTES AND REGULATIONS. The Seller warrants that all merchandise delivered pursuant to this invoice has been manufactured in accordance with the provisions of the Fair Labor Standards Act of 1938, as amended. 2. WARRANTIES. Seller warrants that the product sold hereunder is in conformity with its current specifications therefor. THERE IS NO
Buyer-Seller Relationships 549 WARRANTY THAT PRODUCT SOLD HEREUNDER SHALL BE FIT FOR ANY PARTICULAR PURPOSE, NOR IS THERE ANY WARRANTY OF MERCHANTABILITY OR ANY OTHER WARRANTY, EXPRESS OR IMPLIED, EXCEPT AS EXPRESSLY HEREIN SET FORTH. Buyer expressly agrees that Seller's liability and Buyer's exclusive remedy for breach of any warranty shall be limited to the return of the purchase price of the products sold hereunder. Seller shall in no case be liable for consequential damages. Any recommendations for the use of the product, or equipment, materials or apparatus in conjuction therewith, are based on Seller's best judgment, but there is no warranty of results to be obtained, and no liability in connection therewith. Any claims against Seller for defects in product must be presented in writing with thirty (30) days after discovery of such defect, provided that Buyer must, in any case, commence any action for breach of contract not later than one (1) year from the date of sale. 3. PRICE. In addition to the purchase price, Buyer shall be responsible for all sales, use, excise, property or similar taxes which Seller is required to collect or pay in connection with the sale of the goods to the Buyer. 4. PATENT INDEMNITY. Seller shall not be liable for infringement of any patent, domestic or foreign, arising out of the use of the material covered by this order. 5. OTHER INDEMNITY. If Buyer has submitted any formulas or specifications and directed Seller to comply therewith, Buyer agrees to indemnify and hold Seller harmless against any and all damages, costs, expenses and other liabilities arising out of such compliance, including but not limited to any liability based on claims of infringement by third parties. 6. TRANSFER OF TITLE. Title to the goods shall be in Seller until it passes the f.o.b. point indicated on the reverse side hereof, notwithstanding the fact that Buyer may have furnished raw materials. 7. COMPLETE AGREEMENT. This instrument contains all the terms and conditions with respect to the sale and purchase of the merchandise named herein. No modification of these terms and conditions shall be of any force, or effect, unless in writing and signed by the party claimed to be bound thereby. Further, no modification shall be effected by the acknowledgement or acceptance of purchase order forms containing different conditions. The capitalized material set forth in Section 2 must be printed in solid caps on the final form, since the Uniform Commercial Code invalidates such an exclusion, if it is not displayed prominently. In many instances, it has become advisable to stipulate carefully the specifications of finished aerosols and/or their components, in the event substandard materials are received and rejection by the buyer is contested by the supplier. A typical specification for a standard aerosol overcap, for instance, would include: Supplier Sunbeam Plastics, Inc. Construction #211 double shell linear polyethylene Color Yellow 1-0962 Print 11-2-65 The print should include specifications for all size relationships. Similar specifications can be obtained for containers, valves, shippers, chemicals and other raw materials. Finished aerosol specifications are usually generated by the buyer (or by the seller with buyer's approval). Quite often all these product specifications are gathered into a manual which is used for compliance with the terms set forth in the buyer's purchase order. In most cases the seller is given purchasing latitude, so that he may direct orders to one or more of several approved raw material suppliers. The manual will usually stipulate those suppliers whose products have been evaluated and found satisfactory. In the example above, other aerosol cap suppliers might be listed as: Gilbert Plastics, Inc. Armirotto Tool Co. Landis Plastics, Inc. Imperial Plastics, Inc. #309; Yellow P-71794 #30D; Yellow No. 1 W211 D.S.; Yellow P-121 #2500-D; Yellow TM In many instances, for a container supplier to become an approved supplier, a "Container Warranty Agreement" must be supplied to the buyer:
The Aerosol Handbook Container Warranty Agreement Seller: True Blue Can Company, Inc., 225 W. Harmony Avenue, Park Forest, IL. 60072. Buyer: John A. Doe Aerosol Company, Inc. 16 Third Avenue, Danville, IL., 61832. The True Blue Can Company, Inc. ("Seller") and Buyer agree for the years 1982, 1983 and 1984 as follows: 1. Anything in any Contract or Acknowledgement of Seller for sale to Buyer of containers for the end-use designated herein to the contrary notwithstanding, Seller extends, to Buyer only, its special warranty that the containers subject to this agreement will: i. be merchantable and fit for designated end-use, ii. have the shelf-life specified below, and iii. be equal to specifications THIS WARRANTY, HOWEVER, IS GRANTED SUBJECT TO THE FOLLOWING LIMITATIONS: (a) Shelf-life shall be computed from container filling date, which must be clearly shown by coding on containers, on cartons, or, subject to seller's prior written approval, at another place. (b) Seller shall not be liable under any circumstances to Buyer or any other person for container failure where the containers are not assembled, filled, closed, handled, used, warehoused, or distributed in accordance with the customary good commercial practices of the trade, or when any or all applicable DOT regulations have not been fully complied with. (c) Containers are to be filled with Buyer's product identified in Section (f) of this agreement, samples of which have been made available to Seller for such tests as Seller may require. (d) Buyer shall provide Seller with samples of the product and containers involved when presenting a claim for container failure. (e) Seller may withdraw this warranty forthwith in its sole discretion, in whole or in part, upon written notice to Buyer, but the withdrawal shall not affect the warranty with respect to containers delivered prior to the notice of withdrawal. (f) The shelf life applicable to the Buyer's products is as follows: Container Size-Style Specifications 211 x604 aerosol Body 0.25#ETP, 2/98 solder. Btm. 0.25#ETP, 999-compound. Top 0.50#ETP, 999-compound End-Use of Product Room Spray Buyer's Product 9999-11 Identification Packed under at least 15 "Hg° of vacuum Container Shelf Life 12 months. The above container specifications pertain only when the propellent equilibrium pressure in the product at 70°F is 60 psig or less at 70°F and 140 psig or less at 130°F. If this warranty is withdrawn, in whole or in part, for any reason, SELLER MAKES NO WARRANTY, EXPRESS, IMPLIED OR STATUTORY, AND SELLS THE AFFECTED CONTAINERS AS IS, except that Seller will be responsible for faulty workmanship and use of imperfect materials. Accepted: TRUE BLUE CAN COMPANY, INC. By: Tide Date: Buyer: JOHN A. DOE AEROSOL CO., INC. By: Tide: Date: Whenever a marketer, a contract filler or a third party wishes to divulge proprietary information for any purpose, a formal "Secrecy Agreement" may be presented for die signature of the firm designated to receive
Buyer-Seller Relationships 551 such information. Sometimes this data is released for purposes of evaluation and determination of the feasibility of putting it to commercial use. In other case the information is made available to permit a contract filler to operate adequately under filling contracts. A typical agreement is worded as follows: CONFIDENTIALITY AGREEMENT This instrument shall constitute an agreement on the transfer and handling of confidential information regarding Product X, from the True Blue Company to the John A. Doe Aerosol Company, Inc. 1. It is agreed that the John A. Doe Aerosol Company, Inc. (JADAC) shall maintain as secret and confidential any and all data, specifications and information obtained from the True Blue Company (TBC) with respect to Product X. JADAC will also limit access of TBC's information to such of JADAC's employees as may reasonably require same for accomplishment of the purpose for which the transfer of such information is being made. 2. JADAC also agrees not to itself independently use, practice or exploit any portion or all of such information and/or details with respect to Product X insofar as it is to be held in strict confidence by JADAC pursuant to this letter of agreement. 3. Under no circumstances will JADAC divulge any portion or all of such information and/or detail with respect to Product X to the ABC Company, or to any employees or representatives of the ABC Company, of which JADAC is a wholly- owned subsidiary. 4. The above three paragraphs shall be limited in time to the duration of any contractual relations between TBC and JADAC, plus an additional five years, and shall not, by their terms or implications, apply to public information, apply to information which JADAC can establish by competent proof was in its possession prior to the time of disclosure by TBC, or apply to information which JADAC receives on a non-confidential basis from a third party, provided that JADAC has no reason to believe that such information was obtained on a confidential basis directly or indirectly from TBC. 5. JADAC shall return all segregated papers pertaining to the secret and confidential information concerning the product covered by this agreement upon termination of contractual relations between TBC and JADAC, relating to Product X. If this agreement meets with your approval, please execute the enclosed duplicate copy and return to the TBC company for recording. Signed: For the True Blue Company, Inc. Date: Approved for the John A. Doe Company, Inc. Signed: Title: Date: While "Confidentiality Agreements" are quite popular, they do have shortcomings. By signing such a document a filler may find that his research becomes stifled in the area covered. On the other hand, fillers cannot totally divorce themselves of their knowledge of topics covered under secrecy agreements, when considering innovations, and are at times tempted to modify their secret information sufficiently to put it to the use of others. Recognizing this possibility, some companies insist on secrecy agreements, but still deliver certain key ingredients to the filler under a code designation.
553 AEROSOL FILLERS 17 Data reported in this listing of aerosol fillers and their filling capabilities was obtained from information supplied by the various companies. Proofs of the listings were sent to the companies in April, 1982—and corrections made as late as August, 1982. This information is given to identify the most recent date when the addresses, phone numbers and personnel were checked. Obviously, this information will change with time — and must be kept up to date to be of real use. We shall appreciate being advised of any errors or omissions so they may be corrected in future editions. ACCRA PAC, INC. 2730 Middlebury St. Elkhart, IN 46516 219/295-0000 President — Satish Shah Materials Management — Praful Palan Sales — SherwinJ. Klein Technical Services — Robert M. Smith Manufacturing—Dan Blankenship Chemist — Stewart Butters Finance — Richard D. Russell Director of Mfg. — Dennis J. Brosh 4 filling lines: capacity 50 MM units per year Fill for others and also fill and market some products of own Filling capability: T-t-V and U-t-C pressure filling, compressed gas, glass bottles, and non-aerosol filling Fill: household aerosols, automotive, pesticides, industrial, pharmaceuticals, powder aerosols, cosmetics, colognes and perfumes, glass aerosols and C02 products Offer blow molding and silk screening services Trade names: "Cyclo" "Kem Krest" "T.F.X." and "Performer" for automotive chemicals, household products and general purpose chemicals/cleaners ADVANCE AEROSOL & CHEMICAL CO. 172 S. Carter St. Genoa City, WI 53128 414/279-5151 President — Thomas K. Gabbo Director Research — Thomas K. Gabbo 2 filling lines. Fill for others and also fill and market some products of own Filling capability: T-t-V pressure filling and non-aerosol filling Fill: household aerosols, automotive, paints, industrial and CO, products. Trade Names: "Advance" (household, industrial and automotive aerosols and spray paints.) AERKO INTERNATIONAL CORP. 516 N.E. 34th St. Ft. Lauderdale, FL 33334 305/565-8475 President — Dr. R.E. Robinson Director Purchasing—Dr. R.E. Robinson Director Sales —Michael F. Dallett IV Director Research — Dr. R.E. Robinson Director Quality Assurance — Michael F. Dallett Iv
554 The Aerosol Handbook 2 filling lines: capacity 5 MM units per year Fill for trade and also fill and market some aerosol products of own. Filling capability: pressure filling, glass bottle filling, compressed gas filling, and Septro cans as well as non- aerosol products Fill: household aerosols, automotive, paints, industrial, colognes and perfumes, C02 products. AEROFILL, INC. 7 Turner Place Piscataway, NJ 08854 201/752-1010 President — Ronald Pontolilo AERO-KING, INC. 1530 Stillwell Ave. Bronx, NY 10461 212/823-8300 President — H. Edwards one filling line Fill for others and also fill and market some products of own. Filling capability: T-t-V pressure filling, powder and non-aerosol filling Fill: household aerosols, pesticides, industrial and CO, products. AEROPAK DIVISION (See DeMert & Dougherty) AEROSOL FILLERS, INC. 5485 Ramsay Road St. Hubert, Quebec, Canada J3Y 5S8 514/58-4040 President — A. S. Clarke director Purchasing—F. Schimmel Director Sales — R. York Director Research — W. Schlichtig Dirctor Quality Assurance — W. Schlichtig 5 filling lines: capacity 8 MM units per year Fill for others and also fill and market some aerosol products of own. Filling capability: pressure fill T-t-V and U-t-C, powder fill, compressed gases, glass bottles, partitioned dispensers and non-aerosols. Fill: household aerosols, automotive, pesticides, industrial, pharmaceuticals, powders, cosmetics, colognes and perfumes, glass aerosols and C02 products. Trade names: "Biolan" (hair spray, air freshener, disinfectant deodorizer, furniture polish, window cleaner). AEROSOL PAINT PACKAGING, INC. 4730 Astoria Circle Anaheim, CA 92807 714/998-4676 President — Harvey McKay Director of Purchasing— Linda McKay Director of Research — Than Myint Fill for trade only Fill: aerosol paints AEROSOL RESEARCH LABORATORIES, INC. 606 South St. Holbrook, MA 02343 617/767-2593 President — Alan R. Levine Director Purchasing—Melvin Levine Director Quality Assurance—Judy O'Bryant 2 filling lines: capacity 10 MM units per year Fill exclusively for the trade Filling capability: T-t-V pressure fill, powder fill, compressed gas, glass bottles and non-aerosols Fill: household aerosols, automotive, pesticides, industrial, powder aerosols, cosmetics, glass aerosols and C02 products. AEROSOL SERVICES COMPANY, INC. 425 S. Ninth Ave. Industry, CA 91746 213/968-8531 President — Walter K. Lim Vice-President—Howard C. Lim 6 filling lines: capacity 51 MM units per year Fill exclusively for the trade Filling capability: T-t-V and U-t-C pressure filling, compressed gas, glass bottles, partitioned dispensers, collapsible tubes and non-aerosol filling. Fill: household aerosols, automotive, industrial, pharmaceuticals, cosmetics, colognes and perfumes, glass aerosols and C02 products. AEROSOL SYSTEMS, INC. 9150 Valley View Road Macedonia, OH 44056 216/467-4195 President — Larry Albright Vice Presicent Manufacturing — William Bonham Executive Vice President—Jerry West Vice President Research and Development—Lloyd Planner Manager National Accounts — Hal Brady 5 filling lines: capacity 50 MM units per year Fill exclusively for the trade Filling capability: T-t-V pressure fill, U-t-C pressure fill, compressed gas. Fill: household aerosols, automotive, paints, pesticides, industrial and C02 products. AEROSOL WEST 2595 Katherine Ave. Ventura, CA 93003 805/644-1193 Director Purchasing—Robert Hamming 3 filling lines: capacity 12 MM units per year Fill exclusively for the trade Filling capability: T-t-V and U-t-C pressure filling, compressed gas, glass bottles, partitioned dispensers and non-aerosol filling. Fill: household aerosols, automotive, paints, pesticides, industrial, pharmaceuticals, cosmetics, colognes and perfumes, glass aerosols and C02 products. AERVOE-PACIFIC COMPANY, INC. 2424 Merced St. San Leandro, CA 94577 415/351-4860 President — David A. Williams Director Sales — Sandra Arthur Technical Director —Paul J. O'Neill
Aerosol Fillers 555 3 filling lines: capacity 10 MM units per year Fill for others and also fill and market some aerosol products of own Filling capability: T-t-V pressure fill, compressed gas and non-aerosol products Fill: household aerosols, automotive, paints, pesticides, industrial and C02 products. Trade names: "Aer-Voe" (industrial lubricants, cleaners and paints); "Athena" (art and craft paints); "Cor-On" (decorator paints and automotive chemicals) AIROSOL COMPANY, INC. 525 North 11th St. Neodesha, KS 66757 316/325-2667 President—John Matthews Director Purchasing — Carl Stratemeier 4 filling lines: capacity 20 MM units per year Fill for others and also fill and market some products of own Filling capability: T-t-V and U-t-C pressure filling, non- aerosol filling. Fill: automotive aerosols, pesticides, C02 products. AMERICAN AEROSOLS, INC. 6600 N. Ogallah St. Chicago, IL 60631 President — RoberJ. Ken- Fill mainly paints AMERICAN AEROSOLS, INC. 636 E. 40th St. Holland, MI 49423 1-616/372-7811 President —Joe Knoll Director Purchasing—Dale Knoll Executive V.P. — Ronald Rhea V.P. Sales — Roger Scholten Technical Director — Paul Boesenecker Director Quality Assurance — Kevin Armstrong 10 filling lines: capacity 100 MM units per year Fill exclusively for the trade Filling capability: T-t-V and U-t-C pressure filling, comp. gas, non-aerosol filling and plastics Fill: household aerosols, automotive, paints, pesticides, industrial, cosmetics and C02 products. AMERICAN JETWAY CORP. 34136 Myrtle St. Wayne, MI 48184 313/721-5930 President — Frank Acitelli Director Purchasing—Janice Germann Director Sales — Frank Acitelli Director Research —John Roach Director Quality Assurance — Chuck Quint Fill exclusively for the trade Filling capability: T-t-V pressure filling, powder filling, compressed gas, and non-aerosol Fill: industrial aerosols, paints, pesticides, powder aerosols and C02 products. AMREP INC. (formerly Aero Mist, Inc.) 990 Industrial Park Drive Marietta, GA 30062 404/422-2071 President—John R. Doyle Director Purchasing—Jerry Satherfield Director Sales — Daniel E. Ritter Director Research — Toney Jackson Director Quality Assurance — Debbie Gifford 2 filling lines: capacity 15 MM units per year Fill for others and also fill and market some products of own Filling capability: T-t-V and U-t-C pressure filling, compressed gas Fill: household aerosols, automotive, pesticides, industrial and C02 products. APOLLO INDUSTRIES, INC. 1850 S. Cobb Industrial Blvd. Smyrna, GA 30080 404/433-0210 President — Steve P. Theofilos Director Purchasing—Maria S. Theo General Manager—John Hennecy 2 filling lines: capacity 5 MM units per year Fill for others and also fill and market some products of own. Filling capability: U-t-C pressure pressure filling, compressed gas. Fill: household aerosols, automotive, paints, pesticides, industrial, C02 products. ARMSTRONG LABORATORIES, INC. Division ATI, Inc. 423 LaGrange St. West Roxbury, MA 02132 General Manager — Harvey Mintzer Sales — Donald Lakin Purchasing—Wilfred Roberge Technical Director—Arthur Melvin Specialize in pharmaceuticals, breath fresheners, glass and aluminum tube filling ARMSTRONG-LANG A Division of CCL Industries Inc. 26 Waterman Ave. Toronto, Ontario M4B 1Y5 Canada 416/755-9271 Executive V.P. — E.G. Johnston General Manager — Helve Hamley Plant Manager — Barry Nickason Technical Manager — Andrew Halasz Divisional Controller—Maurice Smith Sales Manager—Jacques Cote Filling capability: T-t-V pressure filling, powder filling, compressed gas, glass bottles, non-aerosol filling and cosmetic-drug powder products. Fill: pharmaceuticals, powder aerosols, cosmetics, colognes and perfumes, glass aerosols and C02 products. CHEM SPRAY DIVISION ATI, Inc. 5 Taft Road Totowa, NJ 07512 201/785-0333 General Manager—John D. Shepherd Sales — Roger Gabriel Purchasing—Barbara Semeraro Technical Director—Vincent Biondi 2 aerosol lines
556 ATI, INC. 5 Taft Road Totowa, NJ 07512 201-785-0333 President —H.R. Shepherd Director Corporate Purchasing—R.C. Patane Vice President, Sales — Fred Presant Director Quality Assurance — Fred Presant Divisions: Armstrong Laboratories Chem Spray Division Fill exclusively for the trade. Filling capability: T-t-V and U-t-C pressure fill, powder fill, compressed gas, glass bottles, partitioned dispensers and non-aerosol filling. Fill: household aerosols, automotive, pesticides, industrial, foods, pharmaceuticals, powder aerosols, cosmetics, colognes and perfumes, glass aerosols, C02 products and solid sticks. BARR COMPANY Division of Pittway Corp. 6100 West Howard St. Niles, IL 60648 312/775-7700 "Chief Executive Officer—George Barr President — Howard Isenberg Director Sales — David N. Parker Technical Director — Mark Jagusiak Director Quality Assurance — Stanley Stavropolous Purchasing Director—Judy Adamoski 16 filling lines Fill exclusively for the trade Filling capability: T-t-V and U-t-C Pressure filling, powder filling, partitioned dispensers and non-aerosol filling. Fill: household aerosols, automotive, industrial, foods, pharmaceuticals, powder aerosols, and cosmetics. BARRETT CHEMICAL CO. H & Luzerne Sts. Philadelphia, PA 19124 215/425-6880 President—J.G. Garson Director Purchasing—A Nuneviller Director Sales—J. Pare Director Quality Assurance — F. Pilko 3 filling lines Fill for others and also fill and market some products of own. Filling capability: T-t-V pressure filling, powder filling, compressed gas, glass bottles and non-aerosol filling. Fill: automotive and industrial aerosols, C02 products, prints, powder aerosols. Trade names: "Multifix" (aerosol cleaner), "Pressure Kleen" (aerosol cleaner) CARE LABORATORIES, INC. P.O. Box "F" 3474 Germantown Pike Collegeville, PA 19426 215/279-3777 President — A. Frank Strouse Director Sales — Richard J. Roetling Director Quality Assurance — Mary Ann Stanley One filling line: capacity 4MM units per year Fill for others and also fill and market some products of own The Aerosol Handbook Filling capability: compressed gas Fill: automotive and industrial aerosols, paints, C02 products. CASE-MASON FILLING, INC. 816 Pulaski Highway Joppa, MD 21085 301/679-8900 President — Alfred P. Mason V.P. Director Sales — Allen Case Plant Manager — Wayne Grube 4 filling lines Fill exclusively for the trade Filling capability: T-t-V pressure filling, powder filling, compressed gas, glass bottles and non-aerosol filling. Fill: pharmaceuticals, powder aerosols, cosmetics, colognes and perfumes, glass aerosols and C02 products. CHASE PRODUCTS COMPANY 19th & Gardner Rd. Broadview, IL 6u0153 312/865-1000 Chairman — R.W. Svendsen President — D.R. Virzi Director Purchasing—J. Pucci Director Sales—L. Meldorf Director Research—J.W. Langer Director Quality Assurance — W. Gaston 5 filling lines: capacity 100 MM units per year Fill for others and also fill and market some products of own Filling capability: T-t-V and U-t-C pressure filling, powder filling, compressed gas and non-aerosol filling. Fill: household aerosols, automotive, paints, pesticides, industrial, pharmaceuticals, powder aerosols, cosmetics, colognes and perfumes, and C02 products. Trade names: "Chasemm" (insecticide); "Champion Sprayon" (spray paint); "Color Spray" (spray paint); "Does Wonders" (household spray); "Santa" (aerosol snow); "Valu Plus" (household and personal product aerosols). CHEMAID 100 Mayhill St. Saddle Brook, NJ 07662 201/843-3300 Owner—Roy H. Reiner Manager of Operations — Dana Graham Director of Research — H. Akrongold Director Quality Control—J. Gulino Director of Marketing— S. Jankowitz Aerosol products: Cosmetics CHEMICAL PRODUCTS CO. 10 Beach St. North Warren, PA 16365 814/723-2161 President —T.C. Atwell Diector Purchasing—T.C. Atwell, Jr. Director Sales — T.C. Atwell, Jr. Director Research—T.C. Atwell Director Quality Assurance — T.C. Atwell, Jr. One filling line Fill for others and also fill and market own products. Filling capability: U-t-C pressure filling, compressed gas and non-aerosol filling Fill: industrial aerosol products
Aerosol Fillers 557 CHEM-PAK, INC. 13 Oates Ave., P.O. Box 685 Winchester, VA 22601 703/667-1395 or 667-1341 President — G.P. Duane, Jr. Director Research — S.A. Resan Controller—H. Dalby 2 filling lines: capacity 3MM units per year Fill for others and also fill and market some products of own. Filling capability: T-t-V pressure filling and compressed gas. Fill: automotive aerosols, paints, industrial, and C02 products. Trade names: "Chempakut" (metal cutting oil); "Electro-Sound" (electric guitar pick-up cleaner); "Finger-Ease" (guitar spring lubricant); "Gun Sav'r" (gun lubricant); "Lightning" (penetrant, lubricant); "Metal-Tap" (metal tapping fluid); "Mold Ease" (mold release); "Solve Clean" (solvent cleaner); "Stop Lock" (anti seize compound); "Triple Tool" (lubricant, penetrant, rust preventive); "True Blue" (spotting and fitting blue); "True Scribe" (layout ink); "Water Gard" (rust preventive); "Ways Ease" (machine ways lubricant); "Zero" (contact point cleaner). CHEMSCOPE CORP. 3200 E. Randol Mill Rd. Arlington, TX 76011 817/261-2287 President —Clifton R. Duke Director Purchasing—Hal Applegate Director Sales—Jim Lackey Director Research — Frank Wood Director Quality Assurance — Frank Wood 2 filling lines: capacity 70 MM units per year Fill exclusively for the trade Filling capability: T-t-V and U-t-C pressure filling, non- aerosol filling. Fill: household aerosols, automotive, pesticides, industrial. CHEMSICO, INC. 8494 Chapin Industrial Drive St. Louis, MO 63114 314/427-4886 President —David C. Pratt Director Purchasing—Timothy J. Kuhn Director Sales — Craig E. Roeper Director Research—James J. Albanese, Jr. Director Quality Assurance — Debbie Hertsel Plant Manager — Glen Dorow 3 filling lines: capacity 35 MM units per year Fill exclusively for the trade Filling capability: T-t-V pressure filling, powder fill, compressed gas, aluminum tubes and non-aerosol filling Fill: household aerosols, automotive, pesticides, industrial and C02 products. CHEM-TECH, INC. 6725 Gov. Printz Blvd. Wilmington, DE 19899 302/798-9675 President — C. Ross Donovan, Jr. Vice President — Nicholas Kypraios 2 filling lines Fill for others and also fill and market some products of own. Filling capability: compressed gas and non-aerosol filling Fill: automotive and industrial aerosols. Brand names: LRP/100 (penetrating lube); Slip-It (clear lube) CLAIRE MANUFACTURING CO. 500 Vista Ave. Addison, IL 60101 312/543-7600 President — Thomas H. Ehler V.P. Operations — V.R. Kaspar Director Purchasing—V.R. Kaspar Sales Manager—James Murray 3 filling lines Fill for others and also fill and market some products of own. Filling capability: T-t-V pressure filling and compressed gas. Fill: household aerosols, automotive, pesticides, industrial and C02 products. Trade names: "Fast Kill" (insecticide); "Fly Jinx" (insecticide); "Gleme" (glass cleaner); "Golden Jet" (bee, wasp and hornet killer); "Mister Jinx" (cleaner); "Spray Nox" (insecticide). CLAPP INDUSTRIES CORP. (Subsidiary of Creative Products Corp.) 318 West State St. Potomac, IL 01865 217/982-6468 President — C.H. Clapp, Jr. 2 filling lines: capacity 15 MM units per year COLORADO AEROSOL, INC. 1395 Zuni St. Denver, CO 80204 303/629-7814 Owner —Clifford Pettee Product Manager, Director of Quality Control — David Stickney Director of Research — Clifford Pettee 2 filling lines; capacity 5MM per year Fill: paints, industrial and automotive Fill exclusively for the trade. CONN CHEM A Division of CCL Industries 26 Waterman Ave. Toronto, Ontario M4B 1Y5 Canada 416/755-9271 President — Ted Johnston General Manager — Keith Wilson Technical Director — Bruce Dawson VP Operations — P. Mulder Fill exclusively for the trade. Filling capability: T-t-V and U-t-C pressure filling, powder filling, compressed gas, glass bottles, partitioned dispensers and non-aerosol filling. Fill: household aerosols, automotive, paints, pesticides, industrial, pharmaceuticals, powder aerosols, cosmetics, colognes and perfumes, glass aerosols, and C02 products. Other aerosol contract packaging divisions include: KG Packaging—James Wega, General Manager Armstrong-Lang—Helve Hamley, General Manager
558 The Aerosol Handbook CONNECTICUT AEROSOLS, INC. Division of Accra Pac, Inc. 85 Furniture Row Milford, CT 06460 203/877-3211 President—John Franchini Director Sales — Don Pontolilo Director Research & Quality Assurance —John Frangos Vice President — Alan Gererd 7 filling lines: capacity 50 MM units per year Fill exclusively for the trade Filling capability: T-t-V and U-t-C pressure filling, compressed gas, glass bottles and non-aerosol filling. Fill: household aerosols, automotive, paints, pesticides, industrial, pharmaceuticals, cosmetics, colognes and perfumes, glass aerosols and C02 products. CONTACT INDUSTRIES, INC. (Subsidiary of Safeguard Chemical Corp.) 641 Dowd Ave. Elizabeth, NJ 07201 201/351-5900 800/526-6832 President — Poozant Piranian Director Purchasing — Peter Piranian, Jr. Director Sales — Mourad S. Nersesian Director Research — Romesh Goel Director Quality Assurance — Willie Danon 5 filling lines: capacity 60 MM units per year Fill for others and also fill and market some products of own Filling capability: T-t-V and U-t-C pressure filling, powder filling, compressed gas and non-aerosol filling Fill: household aerosols, automotive, paints, pesticides, industrial, powder aerosols, toilet preparations and C02 products. Trade names: "Blackjack" (insecticides, cleaning compounds); "Contact" (sanitary specialties); "Permoseal" (coating for electrical wires); "Safeguard" (chemical specialties); "Slip-A-Lume (aluminum lubricants); "Vandal-X" (graffiti remover); "X-Term" (insecticide). CONTINENTAL LABORATORIES INC. 912 S. State Madrid, IA 50156 515/795-2000 President — Gary E. Loest Manager of Operations — David A. Bequeaith Buyer—Jo Hampton Product Manager — Gary Loest Director of Research — Paul Romitti Director of Marketing—Tom Mahoney 2 filling lines: capacity 2.75 MM units per year Fill: cosmetics, pharmaceuticals, insecticides, animal grooming products, lubricants CREATIVE PRODUCTS CORP. 315 Peck St. New Haven, CT 06513 203/562-5118 President —C.P. Clapp Director Operations — W.G. Clapp Director Sales — S.A. Drab Director Research — C.P. Clapp Director Quality Assurance — H.F. Bogen 3 filling lines: capacity 15 MM units per year. Fill for others and also fill and market some products of own. Filling capability: T-t-V and U-t-C pressure filling, compressed gas, glass bottles, small containers and non- aerosol filling. Fill: household and automotive aerosols, pesticides, industrial, foods, pharmaceuticals, cosmetics, colognes and perfumes, glass aerosols and CO, products. Trade names: "Griddle Mate"T (cooking spray); "Micro-Care"T (microwave oven cleaner). CROWN INDUSTRIAL PRODUCTS CO. 100 State Line Road Hebron, IL 60034 815/648-2424 President — Amos E. Buettell Director Purchasing—Ed Ehring Director Sales — F.G. Scheufler Director Research—Joseph D. Szumlas Director Quality Assurance — Philip T. Miller 3 filling lines: capacity 20 MM units per year Fill for others and also fill and market some products of own. Filling capability: T-t-V pressure filling, compressed gas and non-aerosol filling Fill: household aerosols, automotive, paints, pesticides, industrial, powder aerosols, aviation paints and lubricants and CO, products. Trade names: "All Four" (lubricant); "Fault Finder" (spray for non-destructive testing); "Freeze-It" (electrical spray); "Plastic Mastic" (spray adhesive); "Slix-It" (lubricant); "Spra-Line" (spray paint); "Spra-Tool" (spray device); "Tap-Tool" (spray device). CSA LIMITED, INC. P.O. Box 73308 Houston, TX 77090 713/444-6454 President—Joe Rutland Director Purchasing—Larry Spears Director Sales—James White Director Research —James Sic Director Quality Assurance — Alex Haas 3 filling lines: capacity 15 MM units per year Fill for others and also fill and market own products. Filling capability: T-t-V and U-t-C pressure filling, compressed gas and non-aerosol filling. Fill: household and automotive aerosols, pesticides, industrial and CO, products. Trade names: "CSA" (automotive products); "R-12" (brake fluid, flat fix, etc.) CUSTOM-PAK PRODUCTS, INC. N115 W19150 Edison Drive Germantown, WI 53022 414/251-6180 President — Richard C. Berg Executive Vice President—James R. Berg Director Sales — Richard C. Berg Director Research—James R. Berg Director Quality Assurance — Gary Stott Office Manager—Sheryl D. Grunske 2 filling lines: capacity 1 MM units per year Fill for others and also fill and market own products. Fill: automotive aerosols, paints, industrial and CO, products. Trade names: "Custom Pak" (touch-up paint, welders anti-spatter and nozzle shield).
Aerosol Fillers 559 DEMERT & DOUGHERTY, INC. Aeropak Division 814 Commerce Drive Oak Brook, IL 60521 312/523-5600 President — Leonard Drell Executive Vice President — Steven Drell Director Purchasing—Jack Young Director Sales — Robert Jakoubek Director Research — Charles Scott Director Quality Assurance — Richard Pitkins 3 filling lines: capacity 60 MM units per year Contract Packager and also fill and market some branded products Filling capability: T-t-V and U-t-C pressure filling and non-aerosol filling Fill: household, automotive, industrial, personal care aerosols, colognes and perfumes. Filling facilities also in Coal City, IL and Ontario, Canada DENNISTON CHEMICAL CO. now called U.S. PACKAGING DeSOTO, INC. 1122 St. Charles St. Elgin, IL 60120 312/697-0400 Plant Manager — Terry Szesny Materials Supervisor—Richard Biestek Controller/Sales Mgr.—John Costello Laboratory Supervisor — Milton Arnold One filling line: capacity 8 MM units per year Fill exclusively for the trade Filling capability: U-t-C Pressure filling Fill: aerosol paints DIAMOND AEROSOL CORP. Anthony & Woodglen Rds. Glen Gardner, NJ 08826 201/832-7128 President — George B. Diamond Director Purchasing—Stephen M. Galbavy Director Sales — R. Rowen, Jr. Director Research — Ralph H. Helmrich Director Quality Assurance — Stanley Yunkunis 6 filling lines: capacity 20 MM units per year Fill exclusively for the trade Filling capability: T-t-V pressure filling, compressed gas, glass bottles, partitioned dispensers and non-aerosol filling. Fill: household aerosols, industrial, foods, pharmaceuticals, cosmetics, colognes and perfumes, glass aerosols, C02 products. DUPLI-COLOR PRODUCTS CO. Division of Boyle Midway 1601 Nicholas Blvd. Elk Grove Village, IL 60007 312/439-0600 Executive Vice President—Robert R. Miller Purchasing Director — D.J. Brown Vice President Manufacturing—Ervin R. Karaba Fill primarily aerosol paints for automobiles, matching touch-up colors. DYMON, INC. 3401 Kansas Ave. Kansas City, KS 66106 913/321-5537 President — Ed Rose Director Purchasing— Bill Walker Director Research — Kent Zimmerman 3 filling lines Fill exclusively for the trade Fill: automotive aerosols, pesticides and industrial products ENTERPRISE PRODUCTS CO. 901 E. Third St. Los Angeles, CA 90013 1-213/629-1254 President and Director Purchasing—Arthur Fleishman Director Sales—John Erert Director Research — Chuck Badgely Director Quality Assurance —James Aikens One filling line: capacity 100 thousand units per year Fill for others and also fill and market some products of own. Filling capability: T-t-V pressure filling Fill: household aerosols pesticides and industrial aerosols. Trade names: "Fiesta" (Insecticide); " 'Bye" (insecticide); "3C's" (glass cleaner); "Enviro-San" (surface disinfectant and spray deodorant); "Ov-N-Ez" (oven cleaner). ESKA PACKAGING INC. 1750 Oak St. Lakewood Industrial Park Lakewood, NJ 08701 201/367-4100 President—S. Kirschenbaum 2 filling lines Fill exclusively for the trade Filling capability: T-t-V pressure fill Fill: household aerosols, automotive, pesticides, industrial and C02 products. EVEREADY PRODUCTS CORP. 1101 Belt Line Cleveland, OH 44109 216/661-2755 President — Sam Vandivort V.P. Director Purchasing—John Maloney Plant Manager — Dan Harrington 3 filling lines: capacity 20 MM units per year Fill exclusively for the trade Filing capability: U-t-C pressure filling compressed gas and non-aerosol filling Fill: household aerosols, automotive, paints, industrial and C02 products. FLUID PACKAGING CO. 800 Airport Road Lakewood, NJ 08701 201/367-1000 President — Edmund Bennett, Sr. Exec. V.P. —Joseph F. Somma Financial V.P.—Thomas A. Duffy Technical Director — Paul Phillips Director Sales — Kenneth R. Wanner 2 aerosol filling lines Fill exclusively for the trade
560 The Aerosol Handbook Filling capability: T-t-V and U-t-C Pressure filling, powder filling, compressed gas, glass bottles and non- aerosols Fill: pharmaceuticals, foods, powder aerosols, cosmetics, colognes and perfumes, glass aerosols, C02 products, liquids, solild anti-perspirants, and deodorants. THE FULLER BRUSH COMPANY P.O. Box 729 Westport Addition Great Bend, KS 67530 316/792-1711 President — Leonard Dunlap Director Purchasing—William Laging Director Manufacturing— Henry B. Whitman Cheif Chemist — Phyllis Franke Director Quality Assurance — Wilbur Bennett Director Engineering Services — Larry Gregory 2 lines: capacity 6 MM units per year Fill for others and also fill and market some products of own Filling capability: T-t-V and U-t-C pressure filling; powder filling and non-aerosol filling Fill: household aerosols, pesticides, industrial, cosmetics, colognes and perfumes. Brand name: "Fuller" FULTON CHEMICAL CO. Fulton St. Sumter, SC 29150 803/775-6351 President — R.S. McKenzie Director Purchasing—R.S. McKenzie, Jr. Director Sales—Jerry Robertson Director Research—J.T. Robertson Director Quality Assurance—J-T. Robertson One filling line Fill for others and also fill and market some products of own Filling capability: T-t-V pressure filling and compressed gas. Fill: aerosol paints. Trade names: "Fulton Rustaloy" (aerosol paint). GEBAUER CHEMICAL CO. 9410 St. Catherine Ave. Cleveland, OH 44104 216/271-5252 800/321-9348 President — Ernest W. Rose Jr. Director Quality Assurance — Wallace Goldenbogen One filling line Fill for others and also fill and market some products of own Filling capability: U-t-C pressure filling and glass bottles GEM, INC. One Gem Blvd. Byhalia, MS 38611 601/838-2121 President—John C. Adams, Jr. Director Sales — Leo K. Butler Director Research — Herbert Rosenberg Director Quality Assurance — Stanley J. Miekicki Executive V.P. — Lanier Ferguson 2 filling lines, 2 liquid filling lines: capacity 20 MM units aerosols and 24 MM units non-aerosols Fill for others and also fill and market some products of own Filling capability: T-t-V and U-t-C pressure filling, compressed gas and non-aerosol filling Fill: household aerosols, automotive, pesticides, industrial and C02 products. Trade names: "Dustrap" (dust mop spray); "FT" (hair spray); "Gem"; "Prestige" (household cleaner). GEORGIA-PACIFIC CORPORATION 760 S. Vail MontebeUo, CA 90640 213/724-6530 Resident Manager — Ray Plate Materials Manager—Debbie Sinopoli Director of Sales — Walter Eich Manager Research — Marjorie Besemer Director Quality Assurance — Michael T. Goldstein Sales and Marketing—G.J. Vuskaitus Four filling lines: capacity 31 MM units per year. Filling capability: U-t-C pressure filling and non-aerosol filling. Fill: household aerosols, automotive, pesticides, industrial and cosmetics. Trade mark: "Perform" HOLT LLOYD CORP. (Formerly LPS Research Laboratories) 4647 High Howell Road Tucker, GA 30084 404/934-7800 President — Howard F. Elkins National Production Mgr. — Michael D. Beck National Sales Manager—Henry A. Sacco 3 filling lines: capacity 20 MM units per year Fill for others and also fill and market some products of own. Filling capability: compressed gas Fill: automotive and industrial aerosols. Trade names: "LPS"T (chemical products); "Holts"T (car care products) 2 Filling lines in Atlanta, 1 in Los Angeles HYDROSOL, INC. 455 Frontage Road Burr Ridge, IL 60521 312/789-0840 President — Richard Bretzer V.P. Administration — Ray Marzec Executive V.P. — Barrie Barnett Directors Research — Ed Piszynski and Robert Sipla Director Quality Assurance —Jim Grad V.P. Production — Richard Hanke 3 filling lines: capacity 40 MM units per year Fill for others and also fill and market some products of own Filling capability: T-t-V and non-aerosol filling Fill: household aerosols, automotive, paints, pesticides, industrial and C02 products. Trade names: "Holly Trim" (Christmas tree spray) HYSAN CORP. 919 West 38th St. Chicago, IL 60609 312/376-8900 President — Leonard L. Mednick Directors Purchasing—Jean Serpico and Toni Gurgone V.P. Sales — Thomas Lux V.P. Research and Development — Bernard Berkeley V.P. Manufacturing—John W. Osborn
Aerosol Fillers 561 2 filling lines: capacity 14 MM units per year Fill for others and also fill and market some products of own. Filling capability: T-t-V and U-t-C pressure filling, non- aerosol filling. Fill: automotive aerosols, paints, pesticides, industrial and C02 products. ILLINOIS BRONZE PAINT CO. 300 East Main St. Lake Zurich, IL 60047 312/438-8201 President — Robert S. Rothschild Exec. V.P. — Steve Augoustatos V.P. Mfg. and Director Purchasing — Ralph Cairo V.P. Research —Dr. Donald B. Dahm Mgr. Contract Packaging—Steven J. Moore 2 filling lines: capacity 25 MM units per year. Fill for others and also fill and market some products of own. Filling capability: T-t-V pressure filling and compressed gas. Fill: household and automotive aerosols, aerosol paints, industrial aerosols, and non-aerosol products. I.K.I. MANUFACTURING CO. 107 Maple Court Edgerton, WI 53534 608/884-3411 President — Stanley Midtbo Director Purchasing — Richard J. Engler Director Sales — Lawrence B. Midtbo Director Quality Assurance — Douglas Riesch 6 filling lines: capacity 40 MM units per year Fill exclusively for the trade Filling capability: T-t-V and U-t-C pressure filling, compressed gas. Fill: household aerosols, automotive, industrial and C02 products. JET-AER CORP. 100 Sixth Ave. Paterson, NJ 07524 201/278-8300 President — Harry Friedman Director Purchasing—Judith Warhaftig Director Sales — Bruce Newmark Controller— Frank Bello Director Research & Quality Control — Alan Goldman 4 filling lines: capacity 6 MM units per year Fill for others and also fill some products of own Filling capability: T-t-V pressure filling, compressed gas, glass bottles, miniature aerosols and non-aerosol filling. Fill: household aerosols, automotive, paints, pesticides industrial, glass aerosols and C02 products. K-G PACKAGING A Division of CCL Industries, Inc. P.O. Box 658 8001 Keele St. Concord (Ontario) Canada L4K 1C7 416/669-9855 President — George Noguchi Executive V.P. and General Manager—Jim Wega Sales Manager — Ted Foster Plant Manager — Dave Johnston Materials Manager—Heinrich Maushake Technical Manager — Frank Chau Controller — Don Lounsbury Filling capability: T-t-V and U-t-C pressure filling, compressed gas and non-aerosol filling. Fill: household and automotive aerosols, paints, pesticides and industrial products. KNIGHT OIL CORP. 251 North Comrie Ave. Johnstown, NY 12095 518/762-4591 President — Robert G. Brown Director Purchasing—Michael Pozefsky Director Sales — Stanley Karpinski V.P. Marketing — Edw. L. Brown Director Research — Wm. Ziese Director Quality Assurance — Wm. Ziese One filling line: capacity 1.5 MM units per year Fill for others and also fill and market own products. Filling capability: T-t-V pressure filling. Fill: household aerosols, automotive and paints. Trade names: "Knight's" (glass and stainless steel cleaner, motor paints, carpet dye, hospital spray disinfectant). KONALRAD PRODUCTS, INC. 501 S. Basinger Road Pandora, OH 45877 419/384-3241 Vice President/General Manager — Sherman Everett Purchasing Mgr. —Thomas D. Haley Technical Director — Calvin D. Kalstein 4 filling lines: capacity 25 MM units per year Fill own products and also contract fill for others. Filling capability: U-t-C pressire filling and compressed gas. Fill: household aerosols, automotive, paints, pesticides, industrial and C02 products. Brand names: "Snap" starting fluid. LAWSON CHEMICAL PRODUCTS CO. 19500 South Normandie Ave. Torrance, CA 90502 213/321-4220 President—Jeffry L. Lurkis V.P. Purchasing—F.A. Slomian V.P. Sales —Bud LeFevre Technical Director—Myoung Lee 4 filling lines: capacity 20 MM units per year Fill exclusively for the trade Filling capability: T-t-V pressure filling and non-aerosol filling. Fill: automotive aerosols, paints, and industrial products. LPS RESEARCH LABORATORIES (now Holt Lloyd Corporation) MAGID CORP. 4 Allwood Ave. Central Islip, NY 11751 M B L INDUSTRIES, INC. 3600 W. Carriage Drive Santa Ana, CA 92704 714/557-6505
562 The Aerosol Handbook President — Martin B. Lopata V.P. and Gen. Mgr. — Ian R. Gecker One filling line: capacity 3 MM units per year Fill for others and also fill and market some products of own. Filling capability: T-t-V pressure filling and compressed gas. Hydrocarbon and C02 filling. Fill: household, automotive, pesticides and industrial aerosols. Trade name: "Airysol Brand" (household, industrial, institutional and automotive aerosols) MIDCO PRODUCTS CO. INC 11697 Fairgrove Industrial Blvd. St. Louis, MO 63043 800/325-1765 President — Lawrence R. Leavitt Vice President — Thomas A. Dooley Fill for others and also fill and market some products of own. Filling capability: T-t-V pressure filling, glass bottles and non-aerosol (liquid) filling. Fill: household aerosols, automotive, pesticides, industrial, C02 products and shoe care products. MORTON PHARMACEUTICALS, INC. 1625 N. Highland St. Memphis, TN 38108 901/386-8840 President — William J. Morton Secretary-Treasurer — Wayne Morton 2 filling lines: capacity 1.8 MM units per year Fill for others and also fill and market some products of own Filling capability: powder fill and compressed gas Fill: household aerosols, automotive, industrial and powder aerosols. NATIONAL AEROSOL PRODUCTS CO. (Member of Grow Group, Inc.) 2193 E. 14th St. Los Angeles, CA 90021 213/627-2668 President — Sylvan Lefcoe Vice President — Don L. Schary Director Purchasing—Lucille Tobias Director Research — Alfred Bayer Director Quality Assurance — Alfred Bayer 4 filling lines: capacity 15 MM units per year Fill for others and also fill and market some products of own. Filling capability: T-t-V pressure filling. Fill: household aerosols, automotive, paints, pesticides, industrial, cosmetics, colognes and perfumes and glass aerosols. Trade names: "Growco" (spray paints); "Spray-O- Matic" (spray paints). NEW YORK BRONZE POWDER CO. INC. 201 Bay Ave. Elizabeth, NJ 07201 201/289-4900 President — Sol Ganz Director Purchasing—Bella Guariglia Director Sales — Lawrence Finnegan Director Research — Fred Gartenlaub Director Quality Assurance — Vince Tinello Fill for others and also fill and market some products of own Filling capability: T-t-V pressure filling and non-aerosol filling Fill: automotive and industrial aerosols and paints. Trade names: "No-Prime" (rust proof coating); "NYBCO Products" (aerosol paints); "One Coat" (spray enamel); "One Stroke" (woodgraining paint); "Plus" (spray enamel) THE NOCO COMPANY 23300 Mercantile Road Cleveland, OH 44122 216/464-8131 President—Joseph H. Nook, Jr. Director Purchasing—Joseph H. Nook, Sr. Director Sales — William K. Nook 2 filling lines Fill for others and also fill and market some products of own. Filling capability: powder filling, glass bottles and non- aerosol filling. Fill: automotive aerosols, paints and industrial products. NORTHEAST PACKAGING, INC. 25 Connair Road Orange, CT 06477 203/795-9706 President — Robert J. Catapano Vice-President - Operations — Howard R. Wyllie Fill exclusively for the trade Filling capability: T-t-V pressure filling and non-aerosol filling Fill: household aerosols, automotive, paints, industrial, pharmaceuticals. ORB INDUSTRIES, INC. #2 Race St. P.O. Box 1067 Upland, PA 19015 215/874-2537 President — R.O. Boote Vice President—J.W. Bastian Director Sales — K.A. Cressman 3 filling lines Fill for others and also fill and market some products of own Filling capability: T-t-V pressure filling Fill: paints, pesticides, household and industrial aerosols. PACK/TECH SERVICES, INC. See parent company: Aerofill, Inc. P.E.L. ASSOCIATES, INC. 205 Meister Ave. North Branch, NJ 08876 201/725-6060 President — William J. Lueschen Fill: Household products, insecticides, automotive. PENN CHAMP, INC. (Subsidiary of Bissell, Inc.) P.O. Box 55 East Butler, PA 16029 412/287-8771
Aerosol Fillers 563 Vice President & General Manager— Roger Taylor Plant Manager—John Casey Laboratory Director — Paul Simitoski Office Manager—Jim Weed 9 filling lines: capacity 100 MM units per year Fill for others and also fill and market some products of own. Filling capability: T-t-V pressure filling, compressed gas and non-aerosol filling. Fill: household aerosols, automotive, cosmetics, C02 products. Also petroleum jelly and other paste type products. Trade names: "Breath of Spring" (air freshener); "Penn Champ" (lighter fluid); "One Step" (home care products); "Soft 'n Gentle" (health and beauty aids). PERCY HARMS CORP. 430 South Wheeling Road Wheeling, IL 60090 312/541-7220 President — Percy E. Harms Director Purchasing—Jan Van Der Graaf Director Sales—James E. Harms Director Research—Jan Van Der Graaf Director Quality Assurance —Jan Van Der Graaf Plant Superintendent — Henry P. Harms One filling line: capacity 1.5 MM units per year Fill for others and also fill and market some products of own Filling capability: T-t-V pressure filling Fill: industrial aerosols, adhesives, graphic arts specialties and animal products. Trade names: "Slide" (lubricants, release agents, adhesives, cleaners, coating). PETERSON/PURITAN, INC. Hegeler Lane Danville, IL 61832 217/442-1400 Corporate Headquarters: President — Fred C. Meendsen Executive Vice President — Robert J. Peterson Vice President Sales — Richard L. Clark Vice President R&D — Montfort A. Johnsen Vice President Engineering Services — Dale M. Cook Director of R&D —Donald D. Wolff Midwestern Plant (Danville, IL): General Manager—William E. Dunworth Technical Director—Benjamin Z. Taylor Director of Purchases — C. "Gene" Harris Commercial Manager—David B. Reed Aerosol filling capability: Pressure fill by U-t-C, T-t-V or gasser-shakers. Hydrocarbons, compressed gases or DME. Tinplate or 1" aluminum cans. 5 aerosol lines: 2-shift capacity 135 MM/yr. Fill foods, OTC drugs, pharmaceuticals, cosmetics, household products, automotive products and insecticides. (No paints.) Also fill non-aerosol liquid products. Fill exclusively for trade. East Coast Plant: Martin Street Cumberland, RI 02864 401/333-4200 General Manager — Alfredo (Fred) V. Brancucci Technical Director—Antonetta A. Del Santo Director of Purchases — Patricia K. Papineau Director of Customer Services — Chris Sirr Aerosol filling capability: Pressure fill by U-t-C, T-t-V or gasser-shaker. Hydrocarbons, compressed gases or DME. Tinplate or 1 " aluminum cans. 4 aerosol lines, approximate 2-shift capacity: 100 MM/yr. Fill OTC drugs, pharmaceuticals, cosmetics, household products, automotive products, industrial products, insecticides and also non-aerosol liquid products and sticks. Fill exclusively for the trade. West Coast Plant: 9101 South Sorenson Avenue Santa Fe Springs, CA 90670 213/698-1261 General Manager — Thomas W. Donaldson Technical Director — Lutfi J. Shakhshir Director of Purchases — Ted Bistline Director of Customer Services — Steve Thomas Aerosol filling capability: Pressure fill by U-t-C or T-t- V. Hydrocarbons or compressed gases. Tinplate or 1 " aluminum cans. 2 aerosol lines; approximate 2-shift capacity: 50 MM/yr. Fill OTC drugs, pharmaceuticals, cosmetics, household products, automotive products, industrial products, insecticides and also non-aerosol liquid products. PETERSON/PURITAN, INC. AFFILIATES AEROBAL, S.A. San Lasael No. 12 Lerma, Mexico 905/576-2344 Gerante General — Isaac Eichner Contact: Roy Brown (Productos de Maiz, S.A.) 905-541-3040 Aerosol filling capability: Cold fill or pressure fill by T-t-V only. Hydrocarbons and chlorofluorocarbons. Tinplate, aluminum and glass containers; all sizes. 8 aerosol lines, including four of low volume. Approximate 2-shift capacity: 50 MM/yr. FU1 exclusively for the trade. Also fill non-aerosol liquid products. CORN PRODUCTS COMPANY (SOUTH AFRICA) PTY, LTD. Albany House Victoria Embankment Durban 4001 Republic of South Africa 031-314461-9 General Manager — Clifford Granger Sales Manager — Terry Pace Technical Director — Piet P. A. Theron Production Manager — Rolph von Fintel Director of Safety — Graham Downard Planning and Development Manager — Richard M. Bosworth Aerosol filling capability: Pressure-fill by T-t-V. Hydrocarbons or chlorofluorocarbons. Tinplate containers. 2 aerosol lines; One-shift capacity: 25 MM/yr. Fill household products, including insecticides. Fill for self and occasionally for trade. PLASTI-KOTE, INC. 1000 Lake Road Medina, OH 44256 216/725-4511 President — Patrick W. McKenna Executive Vice President — Robert M. Radigan V.P. and Director Sales —Todd P. Ruppelli Director Research — Francis J. Cachat Director Quality Assurance—John Simatacowlos 5 filling lines: capacity 50 MM units per year Fill for others and also fill and market own products.
564 The Aerosol Handbook Filling capability: T-t-V and U-t-C pressure filling. Fill: automotive aerosols and aerosol paints. Trade names: "Easy Way" (spray paint); "Mr. Spray" (spray paint); "Plasti-Kote" (spray paint). PLAZE, INC. 9401 Watson Industrial Park St. Louis, MO 63126 314/961-3564 President—J.H. Ferring III V.P. Manufacturing and Sales—John Ferring IV Director Quality Assurance—James Kennon 5 filling lines: capacity (2 shifts) 30 MM units per year. Hydrocarbon, C02 and fluorocarbon capacity Fill exclusively for the trade Filling capability: T-t-V and U-t-C pressure filling Fill: household aerosols, automotive, paints, pesticides and industrial products. PRESS PAK, INC. 12720 Stiles Lane Sugarland, TX 77478 713/491-3146 Plant Manager — Richard Leasure Technical Director—Frank Bergson One filling line: capacity 3 MM units per year. Filling capability: T-t-V pressure filling, compressed gas, glass bottles, hydrocarbons, fluorocarbons. Fill: prescription and OTC pharmaceuticals, health care products. PRICE-DRISCOLL CORP. 75 Milbar Blvd. Farmingdale, NY 11735 516/249-4200 President — Robert M. Barth Director Purchasing — Agnes M. Smith Director Sales — Philip C. Barth Director Research—Jeffrey C. Otto Director Quality Assurance — Lisa J. Riggs One filling line: capacity 2.2 MM units per yr. Fill for others and also fill and market some products of own Filling capability: T-t-V pressure filling Fill: industrial aerosols PYROIL CO. 2nd & Mill Albion, IL 62806 618/445-2366 President — H. Gaither Vice President — T.C. Christensen Director Purchasing—Robert Williams Director Sales — George Vandre Director Research—J. Kendall Director Quality Assurance—J. Jacobs 8 filling lines: capacity 50 MM units per year Fill for others and also fill and market some products of own Filling capability: T-t-V and U-t-C pressure filling and non-aerosol filling. Fill: household aerosols, automotive, industrial and CO, products. Trade name: "Pyroil" (starting fluid, deicer, carburetor cleaner, brake parts cleaner). RAABE PAINT CO. 4530 North 124th St. Wauwatosa, WI 53225 414/466-7480 President—Richard G. Raabe V.P. Director Purchasing—Kent A. Raabe Sales Manager — William Armstrong Director Research and Q.A. — DeLos Steinberg 2 filling lines: capacity 10 MM units per year. Fill for others and also fill and market own products. Filling capability: T-t-V pressure filling and compressed gas. Fill: paints Trade names: "Raabe Spray" (automotive touch-up paints, engine enamels, tractor and implement enamels); "Raabe 7 - 7" (all purpose spray paints). RANDOLPH PRODUCTS CO. Park Street East Carlstadt, NJ 07072 201/438-3700 President—John H. Randolph Director Purchasing — Roy Nelson Director Research — Charles Kalfian Director Quality Assurance — Richard Mueller 2 filling lines: capacity 300 thousand units per year. Fill for others and also fill and market own products. Filling capability: T-t-V pressure filling. Fill: automotive and industrial aerosols and aerosol paints. Trade name: 'Randolph' RITE OFF, INC. 1545 5th Industrial Court Bayshore, NY 11706 516/665-6868 President — Howard Rapps Director Purchasing—L. Abbott Director Sales—J. Georgian Director Quality Assurance — Ray Polanski 2 filling lines: capacity 3 MM units per year Fill for others and also fill and market own products. Filling capability: T-t-V pressure and compressed gas filling. Fill: household aerosols, automotive, pesticides, industrial and CO, products. RUDD COMPANY, INC. 1630 15th Ave. West Seattle, WA 98119 206/284-5403 President — Alan M. Park, Sr. General Manager — Mac Park Director Purchasing — Karen Hinkledey Director Sales — Kirby Thordarson Director Research — Hossein Varzandeh Director Quality Assurance —Jack Darcy One filling line: capacity 5 MM units per year Fill for others and also fill and market some products of own. Filling capability: T-t-V pressure and compressed gas filling. Fill: household aerosols, automotive, paints, pharmaceuticals, industrial and C02 products. Trade names: "Hydra-Bond" (aerosol paints); "Rudd Brand" (aerosol paints); "Tartan Brand" (aerosol paints).
Aerosol Fillers 565 SHIELD AEROSOL CO. of CALIFORNIA 5165 G Street Chino, CA 91710 714/628-4707 President — George P. Bates V.P. and General Manager—Edward Borrowe Filling capability: T-t-V and U-t-C pressure filling, glass bottles. All propellents. Fill: household aerosols, automotive, industrial, animal products, insecticides and personal products. SHIELD PACKAGING CO., INC. Peter St. Box 729 Webster, MA 01570 617/949-0900 President — George P. Bates Director Sales — Walton Tenay Fill exclusively for the trade. Fillilng capability: T-t-V pressure filling, powder filling, glass bottles, and non-aerosol filling. Fill: household aerosols, automotive, paints, pesticides, industrial, powder aerosols, cosmetics, colognes and perfumes, glass aerosols, and C02 products. SOUTHEAST PACKAGING CORP. 701 Wharton Circle Atlanta, GA 30336 404/691-7800 President—Samuel D. Garretson Purchasing Manager—Mary Lou O'Connor Material Manager—George Mezulis Technical Director—Thomas J. Vansant Plant Manager—Harold Self 3 filling lines, 3 liquid lines: capacity 100 MM units per year Fill exclusively for the trade Filling capability: U-t-C pressure filling, compressed gas, partitioned dispensers and non-aerosol filling. Fill: household aerosols, automotive, pesticides, industrial, cosmetics and C02 products. SOUTHERN CHEMICAL PRODUCTS CO. 430 Lower Boundary Street Macon, GA 31297 912/746-5147 President — George O. Haskell III Director purchasing — Fred L. Browning Director Sales —Joe A. Davis Director Research — William Greene Director Quality Assurance — William Greene One filling line: capacity 12 MM units per year Fill exclusively for the trade Filling capability: T-t-V pressure filling. Fill: household aerosols, pesticides and industrial products. SOUTHLAND PAINT CO. 1101 Industrial Blvd. Gainesville, TX 75128 817/668-7271 Manager — A. Molsbee SPEER PRODUCTS, INC. (Div. Shirlo Corp.) 4242 B.F. Goodrich Blvd. Memphis, TN 38118 901/362-1950 President — R. Wayne Speer General Manager—Wm. Sabo V.P. Sec. Treas. — H.N. Jacobson Director Sales — E.S. "Stan" Caummisar Technical Director—J.D. Commerford PhD Manager Quality Assurance — Ada Nelson 4 aerosol filling lines, 4 liquid lines: capacity 52 MM units per year. Fill for others and also fill some products for an affiliated company. Filling capability: T-t-V and U-t-C pressure filling, compressed gas, glass bottles and non-aerosol filling. Fill: household aerosols, automotive, pesticides, industrial, cosmetics, colognes and perfumes, glass aerosols and C02 products. Trade names: a sister corporation, Shirlo, Inc., markets "Shu Magic" and "Magic Guard" (shoe care products). SPRAY CAN SPECIALTIES INC. 8960 East 205th St. Lakeville, MN 55044 612/469-3439 Manager of Operations — Charles S. Hanson 1 aerosol filling line; 2)4 MM/yr. SPRAY PRODUCTS CORP. P.O. Box 737 Norristown, PA 19404 215/277-1010 President — Andrew A. Orr Director Purchasing — Warren Howard Director Sales — David M. Miller, Jr. 2 filling lines: capacity 14 MM units per year. Fill for others and also fill and market some of own products. Filling capability: T-t-V pressure filling and compressed gas, hydrocarbons. Fill: automotive aerosols, paints, pesticides and industrial products. Tradenames: "Hotshot" (starting fluid); "Nuts Off' (penetrant); "Orr-Lac" (aerosol paints); "Spray" (paints and chemical specialties). SPRAYON PRODUCTS DIVISION The Sherwin-Williams Co. 26300 Fargo Avenue Bedford Heights, OH 44146 216/292-7400 V.P. Business Unit Mgr. — M.W. Salvaggio Director Purchasing — Robert F. Bradach Marketing Mgr. — E.L. Wigton Technical Director—Jos. W. Marchbank National Sales Manager—J.E. Northcutt 5 filling lines: capacity 100 MM units per year. Fill for others and also fill and market some of own industrial aerosol products. Filling capability: U-t-C pressure filling, cold fill hydrocarbon filling. Fill: automotive aerosols, paints, pesticides, industrial, institutional and C02 products. ALSO AT: 3818 E. Coronado St. Anaheim, CA 92806 714/630-1400
566 The Aerosol Handbook V.P. General Mgr. — Garrett E. Clapp Director Purchasing— H. Weiner Director Sales — Ross Young Director Research — B. Bradstock 2 filling lines: capacity 30 MM units per year. Fill exclusively for the trade Filling capability: U-t-C pressure filling, compressed gas and non-aerosol filling. Fill: household aerosols, automotive, paints, pesticides, industrial and C02 products. SPRAYWAY, INC. 484 Vista Ave. Addison, IL 60101 312/628-0998 President—M.R. Aronson Director Research — N. Carpenter Paints and industrials STANLEY HOME PRODUCTS, INC. (National Contracts Division) 116 Pleasant St. Easthampton, MA 01027 413/527-1000 C.O.B. and Chief Executive Officer—H.L. Tower Materials Manager—H.S. Edelstein President of U.S. Selling Division — G. Stagg Technical Services Manager — G. Trowbridge President of Operations Division — A.F. Regensburger, Jr. Manager Nat'l Contracts Division and Special Projects — B.F. Gedmin 1 filling line: capacity 25 MM units per year Fill for others and also fill and market some products of own Filling capability: T-t-V and U-t-C pressure filling, compressed gas, glass bottles, non-aerosol filling and hydrocarbon filling Fill: Household aerosols, pesticides, industrial, powder aerosols, cosmetics, colognes and perfumes STROEBEL PRODUCTS CO. 3015-21 W. Main St. Louisville, KY 40212 502/589-4422 President—J. Melvin Strobel Director Purchasing—D.A. Strobel Director Sales — M. Wayne Strobel Director Research — Stephen J. Bernauer Director Quality Assurance — Neil Jeffries 4 filling lines: capacity 5 MM units per year Fill for others and also fill and market some products of own Filling capability: T-t-V pressure filling, compressed gas and non-aerosol filling Fill: household and industrial aerosols and C02 products. Trade names: "Instant Shine" "Waxie Spra-Shine" TECHNAIR PACKAGING LABORATORIES 414 E. Inman Ave. Rahway, NJ 07065 201/382-7270 President — Vincent Annarella Director Purchasing—Arthur A. Schrafft, Jr. Director Sales —John Domarecki Director Research and Processing—Marvin Ginsberg V.P. Operations — Dan Wieneke Director Engineering—Fred Taurozzi Director Quality Assurance — Tim Boyce 20 filling lines: capacity 40 MM units per year Fill exclusively for the trade Filling capability: T-t-V and U-t-C pressure filling, powder fill, compressed gas, glass bottles, partitioned dispensers, non-aerosol filling. Fill: household aerosols, powder aerosols, colognes and perfumes, glass aerosols, C02 products, export requirements. TECHNICAL CHEMICAL CO. 10737 Spangler Road Dallas, TX 75220 214/556-1421 President — Howard Dudley Vice President of Purchasing—R. Larson Vice President of Sales — Bill London Vice President Operations—John Kruger 2 filling lines Fill for others and also fill and market some of own products Filling capability: T-t-V and U-t-C pressure filling, compressed gas, and non-aerosol filling (fluids to 5 gals.) Fill: household aerosols, automotive, pesticides, industrial. Trade names: "Certified" (brake and transmission fluid); "Johnson's" (brake and transmission fluid); "Old Dutch" (grease, gear oils, motor oils); "Serco" (refirgerants). TEMPO PRODUCTS CO. 6200 Cochran Rd. Solon, OH 44139 Operations — E.P. Kelley Paint aerosols, automotive, marine and aviation products TESTED PRODUCTS CO. (Div. Rexall Drug Company) 3901 N. Kinsway Blvd. St. Louis, MO 63115 314/383-1234 V.P. Sales & Marketing—L. Stephen Weiss 2 filling lines Fill for others and also fill and market some of own products Fill: household aerosols, foods, pharmaceuticals, and cosmetics. Also fill non-aerosol products. Trade names: "Cara Nome" "Carnegie" "Naturalist" ULTRAMOTIVE CORP. P.O. Box 58 Bethel, VT 05032 802/234-9901 President — Chris Scheindel Filling capability: Hydrocarbons and C02; Specialize in miniature cans and barrier packages UNITED STATES AVIEX CO. 1800 Terminal Road Niles, MI 49120 616/683-6767 President — F.E. Kaiser Director Purchasing—John Campbell Director Sales — Patrick Parks
Aerosol Fillers 567 Director Research — Norman Clear Director Quality Assurance — William Strickland V.P. Finance —Fred Fekrat V.P. Product Management — Craig Bryant 6 filling lines: capacity 20 MM units per year Fill for others and also fill and market some products of own Filling capability: U-t-C pressure filling, compressed gas and non-aerosol filling. Fill: household aerosols, automotive, industrial and C02 products, and others. U.S. PACKAGING 440 Denniston Ct. Wheeling, IL 60090 312/459-5030 President — Robert B. Latousek Director Purchasing—David Campbell Director Research —Joe Carrozzo Director Quality Assurance — Rick Buhay 7 filling lines: capacity 25 MM units peryear Fill exclusively for the trade Filling capability: T-t-V pressure filling, non-aerosol filling Fill: household aerosols, automotive, paints, pesticides, industrial. VIRGINIA CHEMICALS, INC. 3340 West Norfolk Road Portsmouth, VA 23703 804/483-7000 WELLSTON AEROSOL MFG. CO. 105 West "A" St. Wellston, OH 45692 President — Dan H. Lockard WHY-NOT INDUSTRIES, INC. 315 Peck St. New Haven, CT 06513 203/624-2090 President — Robert C. East Secretary-Treasurer — Ruth A. East Vice President—James W. East 3 aerosol filling lines: capacity 2,000 units per day Fill for others and also fill and market some products of own Fill: Household products, paints, industrial, automotive, insescticides, janitorial supplies WILSON AEROSOL INC. Division of Roman Cleanser Box 3836 Wilson, NC 27893 919/237-3107 Manager—John Bulla ZOE CHEMICAL CO. 1801 Falmouth Ave. New Hyde Park, NY 11040 516/354-1043 212/347-6900 President— Edward Axelrod Director Purchasing — Neil Axelrod Director Sales — Sidney J. Kukpetz 6 filjing lines: capacity 50 MM units peryear. Fill for others and also fill and market some products of own. Filling capability: pressure filling, compressed gas glass bottles and non-aerosol filling. Fill: household aerosols, pesticides. President — H.W. Buchanan Director Purchasing — R.G. Yeagley Director Sales—J.J. Gurney Director Research — M.E. Hermes Director Quality Control — R.R. Cash Product Manager—M.E. Thompson One filling line: capacity 20 MM units per year. Fill for others and also fill and market own products. Filling capability: U-t-C pressure filling. Fill: pesticides and industrial aerosols. Trade names: "Lethalaire" (insecticide dispensing systems); "Virchem" (insecticides).
617 6/ 12 (Repellent) d-Con Co., Inc., New York TRADEMARKS In these listings we have tried to assemble as complete a record as possible of current trade names of aerosol products. All known aerosol fillers and marketers have been contacted and asked to give us the trade names they currently use for their products. We have also researched industry trade publications. The reader should keep in mind that the list is by no means complete. Inevitably many names in common use will be missing from our records. Nor should the reader assume that because a trademark is listed that it was necessarily ever used, that it is still in use, or that the company listed as using the mark is still in business, still using the same name, or located in the same city. In many cases trademarks applied for may not have been granted, or if issued may no longer be in use. The companies named may have moved, been absorbed by other companies, or gone out of business. Within these obvious limitations we hope this list, certainly the most extensive and complete ever put together, may be useful to our readers. A-l (Paint) Standard Brand Paint Co., Torrance, CA A.R. 69 (Industrial product) Kem Manufacturing Corp., Tucker, GA ACCENT (Paint) Illinois Bronze Paint Co., Lake Zurich, IL ACRYL-X (Industrial coating) Cerfact Lab: oratories, Tucker, GA ACT (Automotive product) State Chemical Manufacturing Co., Cleveland, OH ACTIFRESH (Clothing and shoe deodorant) Sanitized, Inc., New York ADORN (Hair Spray) Gillette Co., Boston, MA ADVANCE (Household, automotive, industrial and aerosol paints) Advance Aerosol & Chemical Co., Genoa City, WI AERACE (Graffiti remover) Madison Bionics, Franklin Park, IL AERODAG (Industrial product) Acheson Colloids Co., Port Huron, MI AERO-DUSTER, Miller Stephenson Chemical Co., Danbury, CT AEROKROIL (Automotive product) Kano Laboratories, Nashville, TN AEROLAK (Hair spray) DeMert & Dougherty, Inc., Chicago, IL AERVOE (Industrial lubricants, cleaners and paints) Aervoe-Pacific Co., San Leandro, CA AFFAIR (Aerosol topping) Knudsen Corp., Los Angeles, CA AFTATE (Personal product) Schering-Plough Corp., Memphis, TN AFTER FIVE (Cologne) Auvergne et Cie, East Meadow, MA AGS (Automotive products) American Parts Co., file, Houston, TX AIRBORNE (Insecticide) Bulk Chemicals, Gretna, LA AIR DEFENSE (Strategic odor fighter) Fuller Brush Co., Great Bend, KS AIROKILL (Insecticide spray) Airosol Co., Inc., Neodesha, KS AIROSCENT (Air deodorizer) Airosol Co., Inc., Neodesha, KS AIROSOL (Insecticides and repellents) Airosol Co., Neodesha, KS AIRYSOL (Household, industrial, institutional and automotive products) M B L Industries, Inc., Santa Ana, CA ALCARE (Hand sanitizer) Vestal Laboratories, St. Louis, MO
618 The Aerosol Handbook ALLANO (Personal care products) Amway Corp., Ada MI ALL FOUR (Lubricant) Crown Industrial Products Co., Hebron, IL ALL GONE (Household and industrial) Bulk Chemicals, Gretna, LA ALL SET (Hair Spray) Aeropak Division of DeMert & Dougherty, Chicago, IL ALMAY (Hair Spray and anti-perspirant) Almay, Inc., New York ALPHA-DYNE (Germicidal spray) Avmor Ltd., Montreal, Canada ALUMALOC (Paints) Orb Industries, Inc., Upland, PA ALUPENT (Pharmaceutical) Boehringer Ingelheim Ltd., Ridgefield, CT AMBER (Cologne) Lenel Perfumes Inc., Dallas, TX AMBER ROSE (Cologne) Lenel Perfumes, Inc., Dallas, TX AMBUSH (Cosmetic) Dana Perfumes Corp., New York AMBUSH (Insecticide) Sentry Chemical Co., Inc., Stone Mountain, GA AMERICAINE (Pharmaceutical) American Critical Care, McGraw Park, IL AM + MEDIC (First aid spray) Amway Corp., Ada, MI AMWAY (Insecticide) Amway Corp., Ada MI ANT/ ROACH-NIP (Insecticide) Hilo Products, Inc., Glenford, NY ANTI-B (Pharmaceutical) The DePree Co., Holland, MI ANTI CRAWL (Insecticide) Amrep, Inc., Marietta, GA ANTI-CHOC (Anti-static for carpets) Cartier Chemicals, Ltd., Lachine, Quebec, Canada A & P (Insecticides, cosmetics and household products) Great Atlantic & Pacific Tea Co., Inc., Brockport, NY APART (Industrial and automotive products) Cerfact Laboratories, Tucker, GA APPLIANCE (Paint) Illinois Bronze Paint Co., Lake Zurich, IL APPLIANCE MAGIC (Household product) Magic American Chemical Corp., Cleveland, OH AQUA NET (Hair spray) Faberge Inc., New York AQUA-PEL (Automotive product) Petro Chemical Products, Inc., Jacksonville, FL ARAMIS (Hair spray) Estee Lauder, Inc., New York ARM & HAMMER (Oven cleaner) Church & Dwight Co., Inc., Piscataway, NJ ARMATEX (Industrial) Bulk Chemicals, Gretna, LA ARMOR-ALL (Automotive product) American Parts Co., Inc., Houston, TX ARRID (Antiperspirant/ deodorant) Carter- Wallace Inc., New York ASPECTICARE, (Disinfectant spray), Air- wick Industries, Inc., Carlstadt, NJ ATHENA (Arts and crafts products) Aervoe Pacific Co., San Leandro, CA ATLAS (Automotive products) Wm Penn, Cleveland, OH AUDIOTEX (Record and tape care products) G.C. Electronics, Rockford, IL AUTO-PANEL (Automotive touch-up paint) Dupli-Color Products, Elk Grove Village, IL AVANTE (Cologne) Lenel Perfumes Inc., Dallas, TX AXELROD (Whipped cream) Agri-Mark, Inc., Newington, CT B B-11 LUBREX (Automotive lubricant) Berry- man Products, Inc., Arlington, TX B-12 CHEMTOOL (Automotive product) Berryman Products, Inc., Arlington, TX BACTINE (First aid spray) Miles Laboratories, Inc., Elkhart, IN BAKE-On (Industrial product) Hercules Products Division, Alden, NY BANDISEPTIC (Medicated spray bandage) W.T. Rawleigh Co., Freeport, IL BARBASOL, (Shaving cream), Leeming/ Pacquin Division, Pfizer Inc., Parsippany, NJ BARCOLENE (Line of personal products) the Barcolene Company, Holbrook, MA BASKIN-ROBBINS (Whipped cream) Agri- Mark, Inc., Newington, CT BATTERY AID (Automotive) Sentry Chemical Co., Inc., Stone Mountain, CT BEAUTIFUL ENDINGS (Hair spray) Bristol Myers Co., New York BEE BOPPER (Insecticide) Animal Repellents, Inc., Griffin, CT BEE-NIP (Insecticide) Hilo Products, Inc., Glenford, NY BEHOLD (Furniture polish) Drackett Co., Cincinnati, OH BELTACK (Industrial product) Kern Manufacturing Corp., Tucker, GA BELT-EASE (Industrial, automotive) American Grease Stick Co., Muskegon, MI BET (Industrial belt dressing) State Chemical Manufacturing Co., Cleveland, OH BIDETTE (Feminine deodorant) Holland- Rantos Co., Inc., Trenton, NJ BIDETTE MIST (Feminine hygiene deodorant) Youngs Drug Products Corp., Piscataway, NJ BIG 'A' (Paint) American Parts Co., Inc., Houston, TX BIKE AID (Lubricant) Dri-Slide Inc., Fremont, MI BILL BLASS FOR WOMEN (Perfumes and colognes) Revlon, Inc., NY BINACA SPRAY, (Breath freshener), Airwick Industries, Inc., Carlstadt, NJ BIO LAN (Hair spray, air freshener, disinfectant and deodorizer, furniture polish, window cleaner) Aerosol Fillers, Inc., St. Hubert, Que., Canada BISSELL (Household products) Bissell Inc., Grand Rapids, MI BLACK & BEAUTIFUL, (Hair spray), Nestle Le Mur Co., New York BLACK JACK (Insecticide, disinfectant) Safeguard Chemical Corp., Bronx, NY BLACK LEAF, (Insecticide), Black Leaf Products Co., Elgin, IL BLANCHARD (Cologne) Del Laboratories, Inc., Farmingdale, NY BLANCO CHEMICAL (Insecticide) Pet Industries, Inc., Houston, TX BLAND (Hair spray) DeMert & Dougherty, Inc., Chicago, IL BLAST OFF (Automotive, industrial) Darco Industries, Camp Hill, PA BLENDAX (Toothpaste) Blenda, Int'l, Prat- tein, Switzerland BLITZ (Household and industrial) Bulk Chemicals, Gretna, LA BLOCK-OUT (Block-out ink) Diagraph- Bradley Industries, Inc., Herrin, IL BLUE GRASS (Cologne) Elizabeth Arden Inc., New York BLUE SHOVEL (Industrial product) Tech Spray, Inc., Amarillo, TX BLUE STUFF (Industrial product) Tech Spray, Inc., Amarillo, TX BOMB-LUBE (Industrial) Price-Driscoll Corp., Farmingdale, NY BON AMI (Cleaning products) Faultless Starch/Bon Ami Co., Kansas City, MO BONDO (Window cleaner) Dynatron-Bondo, Atlanta, GA BOOT LIFE (Boot cleaner) Sportsmen's Labs, Inc., Anoka, MN BORONIA (Air freshener) Amway Corp., Ada MI
Trademarks 619 BOWL 'N ALL (Toilet cleaner) Caltech Industries, Midland, MI BPS (Automotive paints and finishes) Enterprise Co., Wheeling, IL BRAVURA (Men's toiletries, cosmetics and grooming aids) Speidel, Providence, RI BREATH OF SPRING (Air fresheners) Penn Champ, Inc., East Butler, PA BRIGHT (Starch) The Kroger Co., Cincinnati, OH BRIGHT BEAUTY (Paint) Dupli-Color Products, Elk Grove Villa, IL BRITISH STERLING (Men's toiletries, cosmetics and grooming aids) Speidel, Providence, RI BROOK HILL (Cream and non-dairy toppings) Hunt-Wesson Refrigerated Foods, Fullerton, CA BROWNING (Gun oil and boot dressing) Browning Co., Morgan, UT BRUSH-ON (Shaving cream) Jasco Products, Inc., New Rochelle, NY BRUT (Cologne) Faberge, Inc., New York BRYLCREEM (Hair spray) Beecham Products, Pittsburgh, PA B-S-S (Silicone spray) Barrett Chemical Co., Inc., Philadelphia, PA BUFF-UP (Furniture polish) Amway Corp., Ada, MI BUG-A-BYE, (Insecticide), Penetone Corp., Tenafly, NJ BUG BARRIER (Personal insect repellent) Animal Repellents, Inc., Griffin, GA BUG BOSS (Insecticide) Cline-Buckner, Inc., Cerritos, CA BURLEY (Shaving cream) Shulton, Inc., Memphis, TN BURNSEPTIC (Pharmaceutical) Zee Medical Products Co., Irvine, CA BUTCHER'S (Series of household products) Butcher Polish Co., Marlboro, MA 'BYE (Insecticide) Enterprise Products Co., Los Angeles, CA c C-99 (Release agent) Orb Industries, Inc., Upland, PA CABINET MAGIC (Household product) Magic American Chemical Corp., Cleveland, OH CABLEZE (Industrial coating) Cerfact Laboratories, Tucker, GA CALDECORT (Pharmaceutical) Pennwalt Corp., Rochester, NY CAL CUSTOM (Paint) California Custom Accessories Mfg. Co., Carson, CA CALECHE (Deodorant) Parfums Hermes, Hermark Corp., New York CALECTRO (Record and tape care products) G.C. Electronics, Rockford, IL CAL TEC (Paint) Standard Brands Paint Co., Torrance, CA CALVIN KLEIN (Cosmetics) Minnetonka, Inc., Chaska, MN CAMIE (Industrial aerosols) Camie Campbell Inc., St. Louis, MO CAMICIDE (Insecticide) Camie Campbell Inc., St. Louis, MO CANDLELIGHT (Cologne) Take-Along, Inc., Buffalo, NY CANOE (Cologne and shaving cream) Dana Perfumes Corp., New York CAP (Automotive product) State Chemical Manufacturing Co., Cleveland, OH CARBO TUNE (Automotive product) Kern Manufacturing Corp., Tucker, GA CARESSANT (Cologne) Lenel Perfumes Inc., Dallas, TX CARA NOME (Household, pharmaceuticals and cosmetics) Tested Products Co., St. Louis, MO CARBON BLASTER (Automotive product) Petro Chemical Products, Inc., Jacksonville, FL CARNAUBA (Furniture polish) Fuller Brush Co., Great Bend, KS CARNEGIE (Household, pharmaceuticals and cosmetics) Tested Products Co., St. Louis, MO CARNIVAL (Arts & crafts paints) Star Chemical Co., Inc., Hinsdale, IL CARPET MAGIC (Rug shampoo) Hartz Mountain Corp., Harrison, NJ CARSON'S (Pet spray, insecticide) Carson Chemicals Inc., New Castle, IN CARYL RICHARDS (Hair spray) Faberge Inc., New York CASELL-Massey (Room spray, cologne) Caswell-Massey Co., New York CELEBRATION (Personal product) Fashion Two Twenty, Inc., Aurora, O CELLINI (Cologne) Faberge, Inc., New York CELLO (Air freshener, cleaner, insecticide, furniture poliosh, spot lifter) Cello Corp., Havre de Grace, MD CERAMATROL (Institutional cleaner) J.I. Holcomb Mfg. Co., Cleveland, OH CERFACT (Housekeeping, industrial and automotive products) Cerfact Laboratories, Tucker, GA CERFCIDE (Insecticide) Cerfact Laboratories, Tucker, GA CERFITTIII (Housekeeping product) Cerfact Laboratories, Tucker, GA CERFKILL (Insecticide) Cerfact Laboratories, Tucker, GA CERFLASH (Housekeeping product) Cerfact Laboratories, Tucker, GA CERFORM (Housekeeping product) Cerfact Laboratories, Tucker, GA CERFSECT (Insecticide) Cerfact Laboratories, Tucker, GA CERTIFIED (Brake fluid and transmission fluid) Technical Chemical Co., Dallas, TX CHAIN LIFE (Automotive product) Champions Choice, Inc., Orange, CA CHALKAWAY (Chalkboard cleaner) Rochester Midland, Rochester, NY CHAMPION SPRAYON (Paint) Chase Products Co., Broadview, IL CHARGETTE (Refrigerants, engine starting fluid and de-icer) Airosol Co., Inc., Neo- dessa, KS CHARLIE (Perfumes and colognes) Revlon, Inc., New York CHASEMM (Insecticide) Chase Products Co., Broadview, IL CHEM-PAK(Industrial products) Chem-Pak Inc., Winchester, VA CHEMPAKUT (Metal cutting oil) Chem- Pak, Inc., Winchester, VA CHEM-TECH (Automotive lube) Chem- Tech, Inc., Wilmington, DE CHEMTRUST (Safety solvent) Madison Bionics, Franklin Park, IL CHENANGO (Cologne) Frances Denney, Inc., Philadelphia CHERRY BOMB (Insecticide) Puritan/Churchill Chemical Co., Atlanta, GA CHLORASEPTIC (Pharmaceutical) Norwich-Eaton Pharmaceuticals, Norwich, NY CHOKE-EASE (Automotive) American Grease Stick Co., Muskegon, MI CHROME FOIL (Paint) Madison Bionics, Franklin Park, IL CIARA (Perfumes and colognes) Revlon, Inc., New York CIL (Paint) Cil Paints Inc., Toronto, Ontario, Canada CINDER SUDS (Aerosol soap) Cramer Products, Inc., Gardner, KS CITRACE (Disinfectant) Caltech Industries, Midland, MI CITRO SHIELD (Furniture polish) Spartan Chemical Co., Toledo, OH
620 The Aerosol Handbook CITRU SAN (Deodorizer/ disinfectant) DuBois Chemicals, Cincinnati, OH CLAD SS (Industrial coating) Kem Manufacturing Corp., Tucker, GA CLAIRE BURKE (Cosmetics and personal care products) Minnetonka, Inc., Chaska, MN CLEAR COAT (Industrial coating) Kem Manufacturing Corp., Tucker, GA CLEAR GLOSS/ CLEAR (Interior poly varnish) Behr Process Corp., Santa Ana, CA CLEAR LAC (Paint product) Behr Process Corp., Santa Ana, CA CLEEN & SHINE (Housekeeping product) Cerfact Laboratories, Tucker, GA CLEENO (Waterless hand cleaner) Rochester Midland, Rochester, NY CLINDO (All purpose cleaner) Aeropak Division of DeMert & Dougherty, Chicago, IL CLIPPERCIDE, (Disinfectant-Lubricant- Cleaner-Cooler), King Research Inc., Brooklyn, NY CLOROX (Pre-wash product) Clorox Co., Oakland, CA CLOUT (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA CLR (Glass cleaner) State Chemical Manufacturing Co., Cleveland, OH CM-1 MARKERS (Capillary marker, furniture touch-up) Mohawk Finishing Products, Inc., Amsterdam, NY COAT OF ARMOUR (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA COBRA (Solvent spray bruch) Miller Stephenson Chemical Co., Danbury, CT COLD SPRAY (Pharmaceutical) Zee Medical Products Co., Irvine, CA COLIBRI (Butane refill) Colibri, Providence, RI COLLAGE (Personal product line) McKesson Laboratories Div., Fairfield, CT COLOR MOMENT (Hair color spray), King Research, Inc., Brooklyn, NY COLOR SPRAY (Paint) Chase Products Co., Broadview, IL COMMAND (Hair spray) Alberto-Culver Co., Melrose Park, IL COMPARE (Household product) The Barco- lene Company, Holbrook, MA CONDITION (Skincare product) Clairol, Inc., New York CONTACT (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA CONTACT (Insecticides, cleaners, polishes, paints, lubricants, automotive products) Contact Industries, Inc., Elizabeth, NJ CONTAX, (Degreaser), Stewart-Hall Chemical Corp., Mt. Vernon, NY CONTROL (Furniture polish) James Varley & Sons, Inc., St. Louis, MO COOKING EASE (Fry pan lubricant) CPC International, Inc., Englewood Cliffs, NJ COPPERTONE (Sunburn protective product) Plough, Inc., Memphis, TN CORDAY (Perfume and cologne) Max Factor & Co., Hollywood, CA COR-ON (Decorator paints and automotive chemicals) Aervoe-Pacific Co., San Leandro, CA CORTIFOAM, (Pharmaceutical), Reed & Carnick Pharmaceuticals, Kenilworth, NJ COSMOLINE (Lubricant) E.F. Houghton & Co., Broomall, PA COUNTRY COLORS (Paint) Illinois Bronze Paint Co., Lake Zurich, IL CRAWLER MAULER (Insecticide) Animal Repellents Inc., Griffin, GA CRAZY CLEAN (All purpose cleaner) Spray- way, Inc., Addison, IL CRC (Automotive products) American Parts Co., Inc., Houston, TX CREATIVE (Household, industrial, automotive, insecticide) Creative Chemicals Inc., Palmer, MA CREW (Bathroom cleaner) S.C. Johnson & Son, Inc., Racine, WI CROWN (Industrial product) Crown Industrial Products, Hebron, IL CRUEX (Pharmaceutical) Pennwalt Corp., Rochester, NY CSA (Automotive aerosols) CSA Limited, Inc., Houston, TX C-THRU (Housekeeping product) Cerfact Laboratories, Tucker, GA CUSTOM-PAK (Paint) Custom-Pak Products, Inc., Germantown, WI CUT N' SCRATCH (Pharmaceutical) McKesson Laboratories, Fairfield, CT CUTTER (Insect repellent) Cutter Laboratories, Emeryville, CA CX-110 (Industrial coating) Cerfact Laboratories, Tucker, GA CYCLO (Automotive and household products) Accra Pac, Inc., Elkhart, IN D D-15 (Insecticide) Amway Corp., Ada, MI DAIRY SPRAY (Insecticide) Durvet Inc., Blue Springs, MO DALLAS (Cologne) Lenel Perfumes, Inc., Dallas, TX DAYBREAK (Air freshener) Amway Corp., Ada, MI DAZ'L (Paint) Illinois Bronze Paint Co., Lake Zurich, IL D-CON (Line of Insecticides) d-Con Co., Inc., Mont vale, NJ DCW (Furniture wax) Fuller Brush Co., Great Bend, KS D-D (Deodorant and disinfectant) Rochester Midland, Rochester, NY DEEP ACTION (Cleaner) Hillyard Chemical Co., St. Joseph, MO DEFT (Paint) Cook Paint and Varnish Co., North Kansas City, MO DEFT (Wood finishes) Deft, Inc., Irvine, CA DEFTCO (Wood finishes) Deft, Inc., Irvine, CA DEFTHANE (Wood finishes) Deft, Inc., Irvine, CA DE-HESIVE (Athletic product) Cramer Products, Inc., Gardner, KS DEL (Paints, insecticides, automotive and industrial products) Trigon Corp., Reno, NV DELFEN FOAM (Contraceptive) Consumer Products Division, Raritan, NJ DELITE WHIP (Whipped topping) Longlife Dairy Products, Jacksonville, FL DEMPLEX (Spray paint) U.S. Packaging Corp., Wheeling, IL DEO (Disinfectant/ deodorant) State Chemical Manufacturing Co., Cleveland, OH DERMOPLAST (Pharmaceutical) Ayerst Laboratories, Inc., Rouses Point, NY DE ROTHSCHILD (Cologne) Lenel Perfumes Inc., Dallas, TX DESENEX (Pharmaceutical) Pennwalt Corp., Rochester, NY DESIGN MASTER (Floral paint sprays) Colorado Dye & Chemical, Inc., Boulder, CO DETER (Anti-perspirant) Amway Corp., Ada, MI DIAL (Antiperspirant/ deodorant) Armour Dial, Inc., Scottsdale, AZ D-ICER (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA DIFUSO (Residual insect spray) Tanglefoot Co., Grand Rapids, MI DI-O-CIDE A E (Residual Insecticide) Rochester Midland, Rochester, NY DOES WONDERS (Household spray) Chase Products Co., Broadview, IL DOG-CHECK, (Repellent), Nott Manufacturing Co., Inc., Pleasant Valley, NY
Trademarks 621 DOUBLE ACTION (Insecticide) W.T. Raw- leigh Co., Freeport, IL DOW (Bathroom and oven cleaner) Dow Chemical Co., Indianapolis, IN DPL (Metal protector) Chemtronics, Inc., Hauppauge, NY DRAIN POWER, (Drain cleaner), Airwick Industries, Inc., Carlstadt, NJ DRI •(Industrial moisture displacement product) State Chemical Manufacturing Co., Cleveland, OH DRIFAB (Water repellent product) Amway Corp., Ada, MI DRIONE (Insect spray) Fairfield American Corp., Medina, NY DRIPLESS OIL (Industrial, automotive) American Grease Stick Co., Muskegon, MI DRI-SKID (Industrial coating) Kem Manufacturing Corp., Tucker, GA DRI-SLIDE (Lubricant) Dri-Slide Inc., Fremont, MI DRISTAN (Room vaporizor) Whitehall Laboratories, Inc., New York DRUMMER (Cologne) Auvergne et Cie, Inc., East Longmeadow, MA DRYAD (Personal deodorant) The Andrew Jergens Co., Cincinnati, OH DRY BAN (Antiperspirant/deodorant) Bristol-Myers Co., New York DRY LOOK (Hair spray) Gillette Co., St. Paul, MN D-SECT (Insecticide) DuBois Chemicals, Cincinnati, OH DUET (Disinfectant) Madison Bionics, Franklin Park, IL DUHESIVE SPRAY (Adhesive) DuBois Chemicals, Cincinnati, OH DUPLI-COLOR (Paint) Dupli-Color Products, Elk Grove Villa, IL DUPRO (Metal treating compound) DuBois Chemicals, Cincinnati, OH DURO (Automotive product) Loctite Corp., Cleveland, OH DURON (Industrial coating) Kem Manufacturing Corp., Tucker, GA DUSTAT (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA DUST OFF (Non contact photo cleaner) Falcon Safety Products, Inc., Mountainside, NJ DUSTRAP (Dust mop spray) Gem, Inc., Byhalia, MS DUX BAK (Water repellent, leather care product) Harri Hoffman Co., Inc., Milwaukee, WI DYKEM (Ink and lacquer products) Dykem Co., St. Louis, MO DYNA SOL (Degreaser) James Varley & Sons, Inc., St. Louis, MO DY-TAP (Cutting fluid) Dykem Co., St. Louis, MO E EAR-TICK (Pharmaceutical) Durvet Inc., Blue Springs, MO EASE (Industrial and household) Bulk Chemicals, Gretna, LA EASY CAULKER (Foam Caulk) Scott-Page, Inc., Ridgewood, NJ EASY INSULATOR (Foam insulation product) Scott-Page, Inc., Ridgewood, NJ EASY KOTE (Paint) Standard Brands Paint Co., Torrance, CA EASY ON (Spray starch) Boyle Midway Division, New York EASY WAY (Plastic spray) Plasti-Kote Co., Inc., Medina, OH EASY WEATHER STRIPPER (Caulk) Scott-Page, Inc., Ridgewood, NJ E-BOMB (Insecticide) Plant Marvel Labs, Chicago, IL ECHOLS (Insecticides) Athena Products Corp., Dallas, TX ECON-O-MIST, (Antioxident for printing inks), Braznell Co., St. Louis, MO EDGE (Shaving cream) S.C. Johnson & Son, Inc., Racine, WI EIGHT HEADS (Tape head cleaner) Workman Electronic Products Inc., Sarasota, FL ELC (Industrial solvent cleaner product) State Chemical Manufacturing Co., Cleveland, OH ELECTRIC SENTRY (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA ELECTRO-SOUND (Electric guitar pickup cleaner) Chem-Pak, Inc., Winchester, VA ELECTRO-WASH (Electronic degreaser) Chemtronics, Inc., Hauppauge, NY EMRALON (Industrial product) Acheson Colloids Co., Port Huron, MI ENDCOR(Paint)Dampney Co., Everett, MA END-SECT (Insecticide) Madison Bionics, Franklin Park, IL ENDUST (Dusting aid) Drackett Co., Cincinnati, OH ENGLISH LEATHER, (Hair spray, spray talc and shaving cream), Mem Co., Inc., Northvale, NJ EN RUST (Rust remover) Miller-Stephenson Chemical Co., Danbury, CT EN STAT (Anti-static product) Miller-Stephenson Chemical Co., Danbury, CT ENTACIDE, (Insecticide), Airwick Industries, Inc., Carlstadt, NJ ENTERPRISE (Paints and automotive) Enterprise Co., Wheeling, IL ENTICE (Furniture polish) DuBois Chemicals, Cincinnati, OH ENVIROQUAT (Spray disinfectant) Vestal Laboratories, St. Louis, MO ENVIRO-SAN (Disinfectant and spray deodorant) Enterprise Products Co., Los Angeles, CA EPIFOAM, (Pharmaceutical), Reed & Carn- rick Pharmaceuticals, Kenilworth, NJ EPOXY (Paint) Illinois Bronze Paint Co., Lake Zurich, IL EPRIS (Cologne) Max Factor & Co., Hollywood, CA ETHEX (Degreaser) Madison Bionics, Franklin Park, IL EVER-FRESH (Cream and non-dairy toppings) Hunt-Wesson Refrigerated Foods, Fuller-ton, CA EVERWEAR (Paint) Standard Brands Paint Co., Torrance, CA EXIT (Gum remover) Avmor Ltd., Montreal, Canada EXOTIC (Cologne) Lenel Perfumes Inc., Dallas, TX EXRUST (Industrial product) Kano Laboratories, Nashville, TN EXTERMO JET (Insecticide) Rochester Midland, Rochester, NY EXTRA (Household product) Kix Corp., South San Francisco, CA E-Z DOZIT (Penetrant) Berryman Products, Inc., Arlington, TX E-Z STRIP (Industrial product) Cerfact Laboratories, Tucker, GA F FABRICARE (Fabric treatment product) Mohawk Finishing Products Inc., Amsterdam, NY FABRIC GUARD (Fabric treatment product) Mohawk Finishing Products, Inc., Amsterdam, NY FABSPRAY (Fabric color spray) Zynolyte Products Co., Compton, CA FANCI-TONE (Hair tint) Roux Laboratories, Inc., Jacksonville, FL FANTASQUE (Cologne) Avon Products, Inc., New York FASHION WHIP (Aerosol topping) Knudsen Corp., Los Angeles, CA
622 The Aerosol Handbook FAST FREEZE (Histology cryogenic spray) Lerner Laboratoris, New Haven, CT FAST GRAB (Automotive, industrial) Darco Industries, Camp Hill, PA FAST KILL (Insecticide) Claire Manufacturing Co., Addison, IL FAULT FINDER (Non-destructive testing product) Crown Industrial Products Co., Hebron, IL FAULTLESS (Laundry products) Faultless Starch/ Bon Ami Co., Kansas City, MO FAVOR (Furniture care product) S.C. Johnson & Son., Inc., Racine, WI FDS (Feminine deodorant spray) Alberto- Culver Co., Melrose Park, IL FIESTA (Insecticide) Enterprise Products Co., Los Angeles, CA FINAL NET (Hair spray) Clairol, Inc., Stanford, CT FINGER-EASE (Guitar string lubricant) Chem-Pak, Inc., Winchester, VA FINIS (Household product) Scott's Liquid Gold-Inc, Denver, CO FIRE JET (Fire extinguisher) Fire-Jet Division, D.P. Facility, New York FIRM & DRY (Hair spray) Bonat, Inc., W. Paterson, NJ FIRM GRIP (Non-slip spray) Cramer Products, Inc., Gardner, KS FIRM UP (Hair spray) Bonat, Inc., W. Paterson, NJ FLAW FINDER (Flaw detecting product) American Gas & Chemical, Northvale, NJ FLAW FINDR (Dye penetrant) Met-L-Chek Co., Santa Monica, CA FLEA FLIP (Insecticide) Colonial Products, Inc., Lake Worth, FL FLITE (Golf ball spray), ReNu Products FLORAL MIST (Room freshener) W.T. Rawleigh Co., Freeport, IL FLO-TEXX (Liquid cover-slip) Lerner Laboratories, New Haven, CT FLOWAY (Automotive product) Kano Laboratories, Nashville, TN FLUROSOLV (Industrial product) Kem Manufacturing Corp., Tucker, GA FLUSH OFF (Paint and varnish remover) Cartier Chemicals, Ltd., Lachine, Quebec, Canada FLUX-OFF (Organic flux remover) Chem- tronics, Inc., Hauppauge, NY FLY-A-REST (Insecticide) Ralston Purina Co., St. Louis, MO FLY JINX (Insecticide) Claire Manufacturing Co., Addison, IL FLYS AWAY (Insecticide) Farnam Co., Phoenix, AZ FLY-TOX (Insecticide) Cartier Chemicals, Ltd., Lachine, Quebec, Canada FOAM-A-WAY, (Flexographic inks product), Braznell Co., St. Louis, MO FOAM GUARD (Housekeeping product) Kem Manufacturing Corp., Tucker, GA FOAM-A-FIL (Home insulation product) Filled in Ohio FOAMY (Shaving cream) Gillette Co., St. Paul, MN FOG-A-BUG (Insecticide) Farnam Co., Phoenix, AZ FOILLE (Medicated first aid spray) Blistex Inc., Oak Brook, IL FOM (Carpet cleaner) State Chemical Manufacturing Co., Cleveland, OH FOUNT WIP (Whipped cream) Agri-Mark, Inc., Newington, CT 409 DBC (Disinfectant bathroom cleaner) Clorox Co., Oakland, CA FOUR WAY, (Penetrating lubricant), Pene- tone Corp., Tenafly, NJ FRAGRANT (Hair spray) Bonat Inc., W. Paterson, NJ FREE IT (Industrial lubricant) J.I. Holcomb Mfg. Co., Cleveland, OH FREEZE-IT (Electrical spray) Crown Industrial Products Co., Hebron, IL FREEZ-IT (Refrigerant) Chemtronics, Inc., Hauppauge, NY FREEZ-IT (Electronic cleaner) Workman Electronic Products Inc., Sarasota, FL FREKOTE (Mold lubricant, release agent) FreKote, Inc., Boca Raton, FL FROSTY (Snow-spray) Essex Franke Co., Orange, CT FT (Hair spray) Gem, Inc., Byhalia, MS FUL-SCAT (Insect repellent) Fuller Brush Co., Great Bend, KS FULTON (Paint) Fulton Co., Sumten, SC FUNG-O-SPRAY (Fungicidal spray) Cramer Products, Inc., Gardner, KS FURALL (Insecticide) Farnam Co., Phoenix, AZ FUROX (Pharmaceutical) Durvet, Inc., Blue Springs, MO FUROX (Pharmaceutical) Ralston Purina Co., St. Louis, MO G GALORE (Cologne) Germaine Monteil Cosmetics, Deer Park, NY GALVANIC (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA GALVANIZE (Industrial coating) Kem Manufacturing Corp., Tucker, GA GARAGE MAGIC (Household product) Magic American Chemical Corp., Cleveland, OH G.C. ELECTRONICS (Record and tape care products) G.C. Electronics, Rockford, IL GEISLER (Insecticides and products for birds, dogs and cats) Conagra Pet Products Co., Omaha, NE GEM (Household, automotive, industrial and pesticides) Gem, Inc., Byhalia, MS GEMINESS (Perfume) Max Factor & Co., Hollywood, CA GENERAL PATCH (Spray roof repair) Alta- wood, Inc., Gardena, CA GEOFFREY BEENE-GREY FLANNEL (Shaving cream and deodorant) Jacqueline Cochran, Inc., New York GERM SENTRY (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA GERMEX (Housekeeping product) Kem Manufacturing Corp., Tucker, GA GERMICIDE (Disinfectant spray) W.T. Rawleigh Co., Freeport, IL GLADE (Space deodorant) S.C. Johnson & Son, Inc., Racine, WI GLAMORENE (Upholstery cleaner), Airwick Industries, Inc., Carlstadt, NJ GLEME (Glass cleaner) Claire Manufacturing Co., Addison, IL GLEN FARMS (Cream and non-dairy toppings) Ready Food Products Co., Philadelphia, PA GLIDEZE (Lubricant) Rochester Midland, Rochester, NY GLIS'N (Hair spray) Revlon Realistic Professional Products, Inc., Cincinnati, OH GLORY (Rug cleaner) S.C. Johnson & Son, Inc., Racine, WI GLOVE OIL (Athletic product) Cramer Products, Inc., Gardner, KS GLYCO MIST (Disinfectant deodorant) James Varley & Sons, Inc., St. Louis, MO GOLD EAGLE (Automotive products) Gold Eagle Co., Chicago, IL GOLDEN JET (Insecticide) Claire Manufacturing Co., Addison, IL GOLDEN TOUCH (Fry pan lubricant) Boyle Midway, Cranford, NJ GOLD LABEL MIST, (Odor counteractant) Airwick Industries, Inc., Carlstadt, NJ GOODYEAR (Contact cement) W.J. Ruscoe Co., Akron, OH
Trademarks 623 GRAB (Industrial product) Cerfact Laboratories, Tucker, GA GRAND CHAMPION (Insecticide) Farnam Co., Phoenix, AZ GRANULEX (Prescription drug) Dow B. Hickam Inc., Houston, TX GREASE EATER (Defoaming greaser) Union Carbide Corp., New York GREAT DAY (Paint) Illinois Bronze Paint Co., Lake Zurich, IL GREAT EXPRESSIONS (Paint) Precision Paint Corp., Atlanta, GA GREAT FEELING (Cosmetic) Revlon Realistic Professional Products, Inc., Cincinnati, OH GREAT PROTECTION (Paint) Precision Paint Corp., Atlanta, GA GREAT STUFF (Home insulation product) Insta-Foam Products, Inc., Joliet, IL GREEN GARDE (Insecticide and leaf shine) Encap Products Co., Mt. Prospect, IL GREEN MEADOWS (Air freshener) Amway Corp., Ada, MI GREEN OIL (Penetrating oil) F & H Aerosol Packaging Co., Dallas, TX GRIDDLE MATE (Cooking spray) Creative Products Corp., New Haven, CT GRIME-SOLV (Degreaser), Stewart-Hall Chemical Corp., Mt. Vernon, NY GROWCO (Paints, artist materials) National Aerosol Products Co., Los Angeles, CA GRS (Industrial grease product) State Chemical Manufacturing Co., Cleveland, OH GUCCI (Shave foam) Scannon, Ltd., Parsip- pany, NJ GUM-GO (Cleaner) Hfflyard Chemical Co., St. Joseph, MO GUM REMOVER (Gum remover) Amrep, Inc., Dallas, TX GUNK ENGINE BRITE (Automotive product) Radiator Specialty Co., Charlotte, NC GUN LIFE (Gun cleaner and lubricant) Sportsmen's Labs, Inc., Anoka, MN GUN SAV'R (Gun lubricant) Chem-Pak, Inc., Winchester, VA GYM-FRESH-NEW (Athletic product) Cramer Products, Inc., Gardner, KS H HAIR GLOSSARY (Hair spray) Merle Norman Cosmetics, Los Angeles, CA HALSTON (Shaving cream and antiperspir- ant) Max Factor & Co., Hollywood, CA HALT! (Dog repellent) Animal Repellents, Inc., Griffin, GA HANDI-LUBE (Lubricant) Whitmore Manufacturing Co., Cleveland, OH HANDS OFF (Housekeeping product) Kern Manufacturing Corp., Tucker, GA HARD HAT (Industrial coating) Rust Oleum Corp., Evanston, IL HARTZ (Insecticide and animal grooming products) Hartz Mountain Corp., Harrison, NJ HAYNES (Lubricant for food industry) Haynes Manufacturing Co., Cleveland, OH HEATHER (Personal product) Whitehall Laboratories, Inc., New York HEET (Room vaporizor) Whitehall Laboratories, Inc., New York HELL-ON-ICE (Industrial and institutional housekeeping products) Cerfact Laboratories, Tucker, GA HERCULES HERCULON (Industrial product) Hercules Products Division, Alden, NY HESS (Insecticide) Hess & Clark, Inc., Ashland, OH HIDDEN SUPPORT (Hair spray) Syntex U.S.A., Inc., Palto Alto, CA HI-GLOSS (Personal Product) Duart Manufacturing Co., San Francisco HIL-AIR (Disinfectant and deodorizer) Hill- yard Chemical Co., St. Joseph, MO HILO (Pet products) Hilo Products, Inc., Glenford, NY HIL-TREAT (Cleaner) HUlyard Chemical Co., St. Joseph, MO HI-Q_ (Paint) General Paint & Chemical Co., Cary, IL HI-VIZ (Paint) Valspar Corp., Minneapolis, MN HOBBY HOUSEHOLD (Paint) Illinolis Bronze Paint Co., Lake Zurich, IL HOFFCO (Water repellents, leather care products) Harri Hoffman Co., Inc., Milwaukee, WI HOLIDAY (Insecticide) Hill's Pet Chemicals Inc., Medley, FL HOLLY (Shoe care products) Vangard Chemical Corp., St. Louis, MO HOLLY TRIM (Decorative spray) Aerosol Industries, Bridgeview, IL HOLLYU TRIM (Christmas decoration spray) Hydrosol Inc., Burr Ridge, IL HOLTS (Car care products) Holt Lloyd Corp., Tucker, GA HOMAGIC (Paint and varnish remover) Midco Products Co., Inc., Maryland Hts., MO HOME PRIDE (Air freshener) The Kroger Co., Cincinnati, OH HOPE (Cologne) Frances Denney, Inc., Philadelphia HOPKINS (Insecticide) Hopkins Agricultural Chemical Co., Madison, WI HOSPITAL SPRAY (Disinfectant) Chem- scope Corp., Arlington, TX HOT LATHER (Hot shaving cream) Rexall Drug, St. Louis, MO THE HOT ONE (Hot shaving cream) Gillette Co., Boston, MA HOT SHOT (Insecticides) Conwood Corp., Memphis, TN HOT SHOT (Starting fluid) Spray Products Corp., Norristown, PA HY-DENT (Pharmaceutical) Pascal Co., Inc., Bellevue, WA HYDRA-BOND (Paint) Rudd Co., Seattle, WA I IMAGE (Hair spray) Advance Design Laboratories, Los Angeles, CA IMPERIAL (Paint) Pactra Industries, Inc., Upland, CA IMPULSE (Deodorant, cologne) Lever Brothers Co., New York INHIBISOL (Industrial solvent spray) Penetone Corp., Tenafly, NJ INSEKON (Insecticide) J.I. Holcomb Mfg. Co., Cleveland, OH INSERID (Insecticide) J.I. Holcomb Mfg. Co., Cleveland, OH INSTA-KILL (Insecticide) Kern Manufacturing Corp., Tucker, GA INSTANTBLEND (Food aerosol) Instantwhip Foods, Inc., Columbus, OH INSTANTWHIP (Food topping) Instantwhip Foods, Inc., Columbus, OH INSTANT WORM (Fish bait) Instant Worm, Ltd., Suffern, NY INSULEX (Industrial coating) Kem Manufacturing Corp., Tucker, GA INTERLUDE (Cologne) Frances Denney, Inc., Philadelphia IRONING MAID (Household product) Fuller Brush Co., Great Bend, KS ITCHI-KOOL (Athlete's Foot Spray) Chat- tem Drug & Chemical Co., Chattanooga, TN J JAO-6 (Oil type lubricant) DuBois Chemicals, Cincinnati, OH JC (Adhesive bond spray, tape adherrent and podiatry pre-tape) Larson Laboratories, Inc., Erie, PA
624 The Aerosol Handbook JERGEN'S (Lotion) Andrew Jergens Co., Cincinnati, OH JET (Household products) Airosol Co., Neo- desha, KS JET FLUSH (Industrial products) Sentry Chemical Co., Inc., Stone Mountain, GA JET KILL (Insecticide) Airosol Co., Inc., Neo- desha, KS JET STARCH (Household product) The Bar- colene Company, Holbrook, MA JETZ (Automotive product) Cerfact Laboratories, Tucker, GA JIF JOB (Lubricants) Schaefer Paint Co., Ronks, PA JONTUE (Perfumes and colognes) Revlon, Inc., New York JUMBO WHIP (Whipped topping) Longlife Dairy Products, Jacksonville, FL JUNGLE GARDENIA (Cologne) Germaine Monteil Cosmetics, Deer Park, NY JUST WONDERFUL (Hair spray) Faberge, Inc., New York K KjR (Clothing cleaner) Texize Chemicals Group, Greenville, SC KANDY APPLE (Paint) California Custom Accessories Mfg. Co., Carson, CA KANON (Cologne, deodorant, shave foam) Scannon, Ltd., Parsippany, NJ KEHALOG (Pharmaceutical) E.R. Squibb & Sons, Inc., New Brunswick, NJ KEM-A-LOOSE (Industrial and automotive products) Kem Manufacturing Corp., Tucker, GA KEMELT (Industrial and institutional housekeeping products) Kem Manufacturing Corp., Tucker, GA KEMICA (Housekeeping product) Kem Manufacturing Corp., Tucker, GA KEM KILL-B (Insecticide) Kem Manufacturing Corp., Tucker, GA KEM KREST (Automotive and household products) Accra Pac Inc., Elkhart, IN KEMSECT (Insecticide) Kem Manufacturing Corp., Tucker, GA KEM START (Automotive product) Kem Manufacturing Corp., Tucker, GA KEMTRONIC (Industrial and automotive products) Kem Manufacturing Corp., Tucker, GA KENCO (Paint) Fulton Co., Sumten, SC KERI (Lotion) Westwood Pharmaceuticals, Buffalo, NY KITCHEN GUILD (Whipped topping) Broughton Foods Co., Charleston, WV KLEEN-AIR (Industrial products) Hy-Test 303 Corp., Rutherford, NJ KLEENASEPTIC (Gemicidal cleaner) Air Shields Division, Hatboro, PA KLEEN-FOAM (Industrial products) Hy- Test 303 Corp., Rutherford, NJ KLEEN GUARD (Rug cleaner, furniture polish and dusting aid) Alberto-Culver Co., Melrose Park, IL KLEEN 'N SHINE (Furniture care product) S.C. Johnson & Son, Inc., Racine, WI KLEEN-OUT (Industrial products) Hy-Test 303 Corp., Rutherford, NJ KLEEN-ALERT (Industrial products) Hy- Test 303 Corp., Rutherford, NJ KLEEN-POINT (Industrial products) Hy- Test 303 Corp., Rutherford, NJ KLEERGARD II (Housekeeping product) Kem Manufacturing Corp., Tucker, GA KLENKS (Epoxy enamel) Zynolyte Products Co., Compton, CA KLIX (Household and industrial products) Kix Corp., South San Francisco, CA KNIGHT'S (Cleaners, paints, dyes, disinfectants) Knight Oil Corp., Johnstown, NY KNIGHT'S (Cosmetics) Old 97 Co., Tampa, FL KNIZE (Cologne, room spray) Caswell- Massey Co., New York KNUDSEN REAL WHIP CREAM (Aerosol topping) Knudsen Corp., Los Angeles, CA K.O. (Insecticide) Pioneer Manufacturing, Cleveland, OH K.O.K. (Housekeeping product) Kem Manufacturing Corp., Tucker, GA KONTAK (Spot cleaner) Avmor Ltd., Montreal, Canada KONTACT RESTORER (Contact cleaner) Chemtronics, Inc., Hauppauge, NY KORKAY, (Motor paint, undercoat and penetrant), Korkay, Inc., Broadalbin, NY KOROMEX (Contraceptive foam) Holland- Rantos Co., Inc., Trenton, NJ KOT (Paint) State Chemical Manufacturing Co., Cleveland, OH KRACKS AWAY (Spackling compound) Midco Products Co., Inc., Maryland Hts., MO KREEN (Automotive product) Kano Laboratories, Nashville, TN KROIL (Industrial product) Kano Laboratories, Nashville, TN KRYLON (Paints, automotive and industrial products) Borden, Inc., Norristown, PA KWIK-KARE (Athletic supplies) Kay Laboratories, Inc., San Diego, CA L L-7 LOOSENER (Industrial, automotive) American Grease Stick Co., Muskegon, MI LAFAYETTE (Metalworking product) American Oil & Supply Co., Newark, NJ L'AIMANT (Fragrance) Coty Div., New York LA MAUR (Hair spray) La Maur, Inc., Minneapolis, MN LANOLIN PERFECTION (Hair spray) Bonat Inc., W. Paterson, NJ LARVES (Insecticide) Petrokem Corp., Paterson, NJ LEADER (Insecticide) Safeguard Chemical Corp., Bronx, NY LEAK-TEC (Lead detecting product) American Gas & Chemical, Northvale, NJ LEAN FRY (Fry pan lubricant) Boyle Midway, Cranford, NJ LECTRASOL (Industrial and automotive products) Kem Manufacturing Corp., Tucker, GA LECTRIC-LIKE (Moisture displacer) Madison Bionics, Franklin Park, IL LECTROKEM (Industrial and automotive products) Kem Manufacturing Corp., Tucker, GA LECTRO-SAF (Electrical parts cleaner) DuBois Chemicals, Cincinnati, OH LEMON AID (Household product) Bulk Chemicals, Gretna, LA LEMO-WAX (Institutional cleaner) J.I. Hol- comb Mfg. Co., Cleveland, OH LENEL FOR MEN (Cologne) Lenel Perfumes Inc., Dallas, TX LESTOIL (Household product) Noxell Corp., Baltimore, MD LETHALAIRE (Insecticide dispensing systems) Virginia Chemicals, Inc., Portsmouth, VA LETSGO, (Lubricant), Stewart-Hall Chemical Corp., Mt. Vernon, NY LIBAN (Lice control product) Pfizer, Inc., New York LIFT OFF (Paint and varnish remover) Midco Products Co., Inc., Maryland Hts., MO LIFT OFF (Gum and label remover) Lift Off Inc., San Diego, CA LIGHTNING (Penetrant, lubricant) Chem- Pak, Inc., Winchester, VA LIKE MAGIC (Plant spray insecticide) Enviro-Spray Systems, Inc., Montgomeryville, PA LIKE MAGIC (Furniture polish, disinfectant, rug shampoo, window cleaner) Cello Corp., Havre de Grace, MD
Trademarks 625 LIL GIANT ZAPPER (Personal protection spray) Safety & Security Co., Hardeyville, PA LILT (Home permanent) Proctor & Gamble Co., Cincinnati, OH LIQUASTEEL (Industrial coating) Cerfact Laboratories, Tucker, GA LIQUID GLAZE (Automotive) Liquid Glaze, Inc., Toccoa, GA LIQUID WRENCH (Automotive product) Radiator Specialty Co., Charlotte, NC LIQUINET (Hair spray) Consolidated Royal Chemical Co., Chicago, IL LISTERINE (Breath freshener) Warner-Lambert Co., Morris Plains, NJ LITH-EASE (Industrial) American Grease Stick Co., Muskegon, MI LIVING STEPS (Cosmetic) Bendyne Products, Inc., New York LOCK EASE (Lubricant) American Grease Stick Co., Muskegon, MI LOCTITE (Automotive product) Loctite Corp., Cleveland, OH LONG LIFE (Automotive product) Kern Manufacturing Corp., Tucker, GA THE LOOK (Hair spray) DeMert & Dougherty, Inc., Chicago, IL L'ORIGAN (Perfume) Coty Division, San- ford, NC LOUIS DE PHILLIPPE (Deodorant) Chese- brough-Pond's de Mexico, S.A. de C.V., Cuernavaca, Morelos, Mexico LOVE (Cosmetic line) Chattem Drug & Chemical Co., Chattanooga, TN LPS (Chemical products) Holt Lloyd Corp., Tucker, GA LRP/100 (Penetrating lube) Chem-Tech, Inc., Wilmington, DE LUB (Industrial silicone lubricant) State Chemical Manufacturing Co., Cleveland, OH LUBE ALL (Lubricant) Spartan Chemical Co., Toledo, OH LUBELOC (Industrial product) Cerfact Laboratories, Tucker, GA LUBE-LOK (Lubricant) Electrofilm Inc., Valencia, CA LUBRI-BOND (Lubricant) Electrofilm, Inc., Valencia, CA LUBRICON (Industrial coating) Cerfact Laboratories, Tucker, GA LUBRISIL, (Silicone lubricant), Penetone Corp., Tenafly, NJ LUBRITE (Electronic cleaner) Workman Electronic Products Inc., Sarasota, FL LUSTER GLO (Leaf Polish) Plant Marval Labs, Chicago, IL LUSTER LEAF (Insecticide and leaf shine) Encap Products Co., Mt. Prospect, IL LYSOL (Disinfectant and bathroom cleaner) Lehn & Fink Products Co., Montvale, NJ M MACE (Personal defense irritant spray) Smith & Wesson, Springfield, MA MACE (Anti-mugging aerosol) General Ordinance Equipment Co., Springfield, MA MAGIC CLEANERS (Cleaner polish for formica) Magic American Chemical Corp., Cleveland, OH MAGIC FOAM (Carpet cleaning product) Amway Corp., Ada, MI MAGIC GUARD (Water, oil & soil repellent - shoes & handbags) Shirlo, Inc., Memphis, TN MAGIC GUARD, (Water, oil and soil repellent for shoes and handbags), Speer Products, Inc., Memphis, TN MAGICOLOR (Paints, automotive) Enterprise Co., Wheeling, IL MAGIC SIZING (Spray starch) Armour-Dial, Inc., Chicago, IL MAGIC SPRAY (Paint) Standard Brands Paint Co., Torrance, CA MAJOR ENAMEL (Paint) Standard Brands Paint Co., Torrance, CA MALTER ADIOS (Insecticide) Bulk Chemicals, Gretna, LA MARBLE MAGIC (Household product) Magic American Chemical Corp., Cleveland, OH MARKET BASKET (Starch) The Kroger Co., Cincinnati, OH MARK OFF (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA MARSH (Spray ink, adhesive, silicone) Marsh Stencil Machine Company, Belleville, IL MARY CARTER (Paints, automotive) Enterprise Co., Wheeling, IL MASTERCHEM (Paint) Cook Paint and Varnish Co., North Kansas City, MO MASTER JINX (Cleaner) Claire Manufacturing Co., Addison, IL MATCH-IT (Automotive product) Milwaukee Paint Products, Milwaukee, WI MAYWOOD (Paint and automotive aerosol) Hydrosol, Inc., Burr Ridge, IL MAZOLA NO-STICK, (Cooking pan release agent), Best Foods Unit CPC North America, Englewood Cliffs, NJ MDL (Moisture displacer) Orb Industries, Inc., Upland, PA MDP (Moisture displacer) Orb Industries, Inc., Upland, PA MEDIHALER (Pharmaceutical) Riker Laboratories, Inc., Northridge, CA MEDI-QUIK (First aid spray) Lehn & Fink Co., Montvale, NJ MENNEN DRY (Antiperspirant/deodorant) Mennen Co., Morristown, NJ METALOC (Paints) Orb Industries, Inc., Upland, PA MET-L-CHEK (Dye penetrant) Met-L-Chek Co., Santa Monica, CA METAL-TAP (Metal tapping fluid) Chem- Pak, Inc., Winchester, VA MICATIN (Athlete's Foot spray) Ortho Pharmaceutical Corp., Raritan, NJ MICO (Household and industrial) Modern Industries Inc., Vista, CA MICRO-CARE (Microwave oven cleaner) Creative Products Corp., New Haven, CT MICRO FINISH (Automotive product) Champions Choice, Inc., Orange, CA MICROIL (Industrial product) Kano Laboratories, Nashville, TN MIDGET (Insecticide) Orb Industries, Inc., Upland, PA MIGHTI-PINE (All purpose cleaner) Sterling Drug, Inc., New York MI-KEM (Household and industrial) Modern Industries, Inc., Vista, CA MILL-O-CIDE A E (Insecticide) Rochester Midland, Rochester, NY MINI-FLAKE (Paint) California Custom Accessories Mfg. Co., Carson, CA MINI-MIST (Shampoo) Block Drug Co., Jersey City, NJ MINK DIFFERENCE (Hair spray) Gillette Co., Boston, MA MINUS 62 (Industrial product) Tech Spray, Inc., Amarillo, TX MIRACLE BATH (Tuner cleaner and degreaser) Workman Electronic Products Inc., Sarasota, FL MISS BRECK (Hair spray) Shulton, Inc., Wayne, NJ MISS ROUX (Hair tint) Roux Laboratories, Inc., Jacksonville, FL MISTER REE (Personal product) Fashion Two Twenty, Aurora, OH MISTY (Cleaner, disinfectant, insecticide, automotive) Amrep, Inc., Marietta, GA MMM! WHAT A TAN (Skin care product) 3M Co., St. Paul, MN MNT (Disinfectant/deodorant) State Chemical Manufacturing Co., Cleveland, OH MOHAWK TONE FINISH (Lacquer) Mohawk Finishing Products, Inc., Amsterdam, NY
626 The Aerosol Handbook MOLD-EASE (Mold release) Chem-Pak, Inc., Winchester, VA MOLECTRA (Industrial product) J.I. Hol- comb Mfg. Co., Cleveland, OH MOLY BROWN (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA MOLY GLIDE (Industrial and household) Bulk Chemicals, Gretna, LA MORNY (Room spray, cologne) Caswell- Massey Co., New York MO-SPRAY-CO (Paint) Mobile Paint Manufacturing Co., Inc., Theodore, AL MPG-2 (Lubricant) DuBois Chemicals, Cincinnati, OH MR. JINX (Cleaner) Claire Manufacturing Co., Addison, IL MR. SPRAY (Paint) Plasti-Kote Co., Medina, OH MUGET (Cologne) Coty Division, Sanford, NC MULTIFIX (4-way lube) Barrett Chemical Co., Inc., Philadelphia, PA MULTI-PURPOSE (Insecticide) U.S. Packaging Corp., Wheeling, IL MUNICHEM (Paints, insecticides, industrial and automotive products) Trigon Corp., Reno, NV MURASAKI (Perfume, cologne) Shiseido Cosmetics, New York MUSK (Toiletry) Coty Div., New York N NAIR (Depilatory) Carter Wallace, Inc., Cranbury, NJ NAM-A-LAC (Paint) Mobile Paint Manufacturing Co., Inc., Theodore, AL NATURALIST (Household, pharmaceuticals and cosmetics) Tested Products Co., St. Louis, MO NATURALLY ENRICHED (Hair spray) Fuller Brush Co., Great Bend, KS NEAREST THING TO CHROME (Spray enamel) New York Bronze Powder Co., Elizabeth, NJ NEET (Cosmetic) Whitehall Laboratories, Inc., New York NEO-TERRAMYCIN SCOURS TREATER (Animal health product) Pfizer, Inc., New York NESTLE, (Hair color spray), Nestle Le Mur Co., New York NEUTRO- STATE (Antistatic industrial product) Simco Co., Inc., Hatfield, PA NEVER STIK (Home care product) Amway Corp., Ada, MI NEW IMAGE (Hair spray) Shulton, Inc., Wayne, NJ NIAGRA SPRAY STARCH, (Laundry starch), Best Foods Unit CPC North America, Englewood Cliffs, NJ NI-LATE PLUS (Insecticide) DuBois Chemicals, Cincinnati, OH NILODOR (Deodorizers) Nilodor, Inc., North Canton, OH NITROTAN (Athletic products) Cramer Products, Inc., Gardner, KS NO ARC (Insulating spray) Chemtronics Inc., Hauppauge, NY NO PEST (Insecticides) Texize, Greenville, SC NO PRIME (Rustproof coatig) N.Y. Bronze Powder Co., Elizabeth, NJ NO-SPILLS LIQUID (Air freshener) Cline- Buckner, Inc., Cerritos, CA NOXEMA (Personal product) Noxell Corp., Baltimore, MD NOZZLE-DIP-GEL (Welding and anti-spatter compounds) Weld-Aid Products, Inc., Detroit, MI NOZZLE-KLEEN (Welding, anti-spatter compounds) Weld-Aid Products, Inc., Detroit, MI NP-27 (Pharmaceutical) Norwich-Eaton Pharmaceuticals, Norwich, NY NU FINISH (Paint) Standard Brands Paint Co., Torrance, CA NU-MIST (Hair spray) Jheri Redding Products, Edison, NJ NUTS OFF (Penetrant) Spray Products Corp., Norristown, PA NYBCO (Paints) New York Bronze Powder Co., Inc., Elizabeth, NJ o OAKITE (Solvent degreaser, penetrating oil) Oakite Products, Inc., Berkeley Heights, NJ OAKITE BREAKAWAY (Lubricant for metals) Oakite Products, Inc., Berkeley Heights, NJ OCCLUDE (Pharmaceutical) Pascal Co., Inc., Bellevue, WA ODORGON, (Fuel oil deodorant), Stewart- Hall Chemical Corp., Mt. Vernon, NY ODORITE (Household product) Avmor Ltd., Montreal, Canada ODORONO (Deodorant) Chesebrough-Ponds de Mexico, S.A. de C.V., Cuernavaca, More- los, Mexico OFF! (Insect control product) S.C. Johnson & Son, Inc., Racine, WI OGL (Industrial lubricant) State Chemical Manufacturing Co., Cleveland, OH OIL 'UM UP (Spray lubricant) Altawood, Inc., Gardena, CA OLD 97 (Household product) Old 97 Co., Tampa, FL OLD DUTCH (Grease, gear oils, motor oils) Technical Chemical Co., Dallas, TX OLD SPICE (Cologne and deodorant) American Cyanamid Co., Wayne, NJ OMEGA (Automotive product) Omega, Inc., Carolina, P.R. ONE COAT (Spray enamel) N.Y. Bronze Powder Co., Elizabeth, NJ ONE STEP (Home care products) Penn Champ, Inc., East Butler, PA ONE STROKE (Woodgraining paint) N.Y. Bronze Powder Co., Elizabeth, NJ OPTIMUM BALANCE (Hair product) Lan- vin-Charles of the Ritz, New York ORR-LAC (Paint) Spray Products Corp., Norristown, PA ORTHO (Insecticides, fungicides, herbicides, repellents) Chevron Chemical Co., Ortho Consumer Products Division, San Francisco, CA OSTER (Household spray lube) Sunbeam Appliance Service Co., Chicago, IL OUR PRIDE (Paint) Precision Paint Corp., Atlanta, GA OVEN MAGIC (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA OVEN 'N' GRILL (Home care product) Amway Corp., Ada, MI OV-N-EZ (Oven cleaner) Enterprise Products Co., Los Angeles, CA P PACTRA 'NAMEL (Paint) Pactra Industries, Inc., Upland, CA PALADIN (Primer paint) W.J. Ruscoe Co., Akron, OH PAM (Fry pan spray) Boyle Midway Division, New York PANEL MAGIC (Household product) Magic American Chemical Corp., Cleveland, OH PAN PAL (Frypan lubricant) Blue Cross Laboratories, Inc., Saugus, CA PARK (Personal product) Jewel Home Shopping Service, Inc., Barrington, IL PART-EASE (Industrial, automotive) American Grease Stick Co., Muskegon, MI PCP (Garden products) Hilo Products, Inc., Glenford, NY PEACOCK (Shoe care products) Vangard Chemical Corp., St. Louis, MO PEN (Industrial penetrating fluid) State Chem ical Manufacturing Co., Cleveland, OH
Trademarks 627 PENEPHITE (Industrial product) Kano Laboratories, Nashville, TN PENN CHAMP (Lighter fluid) Penn Champ, Inc., East Butler, PA PEN-T (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA PENTHOUSE (Household product) Star Chemical Co., Inc., Hindale, IL PERFORM (Starch, window cleaner, disinfectant) Georgia-Pacific Corp., Montebello, CA PERFORM (Rust penetrant) Madison Bionics, Franklin Park, IL PERFORMEX (Automotive and household products) Accra Pac, Inc., Elkhart, IN , PERMATEX (Automotive product) Loctite Corp., Cleveland, OH PERMATREET (Magnetic spray) Avmor Ltd., Montreal, Canada PERMOSEAL (Electric wire coating) Contact Industries, Elizabeth, NJ PEST-A-REST (Insecticide) Colonial Products, Inc., Lake Worth, FL PET PROTECTOR (Insecticide) Colonial Products, Inc., Lake Worth, FL PETROCHEM (Rust preventive, chain lubricant and cleaner) Champions Choice, Inc., Anaheim, CA PGR (Industrial paint & gasket remover) State Chemical Manufacturing Co., Cleveland, OH PIERRE CARDIN (Shaving cream and deodorant) Jacqueline Cochran, Inc., New York PINAUD, (Shaving cream), Nestle Le Mur Co., New York PINE SOL (Household cleaner) American Cyanamid Co., Wayne, NJ PLASTIC MASTIC (Spray adhesive) Crown Industrial Products Co., Hebron, IL PLASTI-KOTE (Paint) Plasti-Kote Co., Medina, OH PLAST-N-GLAS (Anti- static cleaner) Chem- tronics, Inc., Hauppauge, NY PLAY (Polish) Madison Bionics, Franklin Park, IL PLEDGE (Furniture care product) S.C. Johnson & Son, Inc., Racine, WI PLUS (Spray enamel) N.Y. Bronze Powder Co., Elizabeth, NJ P/N (Automotive products) K & W Products, Whittier, CA POLYCOTE (Housekeeping product) Kem Manufacturing Corp., Tucker, GA POWDER POLYMER (Hair spray) Clairol, Inc., NY POWER4 (Lubricant, solvent, metal cleaner)' Rochester Midland, Rochester, NY POWER GRIP (Hand grip aid) Power Grip Co., Dover, OH POWER-OFF (Housekeeping product) Cer- fact Laboratories, Tucker, GA POWER-TAC (Adhesive) Orb Industries, Inc., Upland, PA PQ (Industrial lubricant) American Oil & Supply Co., Newark, NJ PRECAINE SPRAY (Pharmaceutical) Pascal Co., Inc., Bellevue, WA PRESSURE KLEEN (Solvent cleaner) Barrett Chemical Co., Inc., Philadelphia, PA PRESTIGE (Household cleaner) Gem, Inc., Byhalia, MS PRESTO (Disinfectant) Safeguard Chemical Corp., Bronx, NY PRESTO (Paint aerosol) Hydrosol, Inc., Burr Ridge, IL PRESTONE (Automotive) Union Carbide Home & Automotive Division, New York PRIMATENE MIST (Pharmaceutical) Whitehall Laboratories, Inc., New York PRINCE MATCHABELLI (Colognes) Chese- brough-Pond's, Clinton, CT PRINCESS VAL (Antiperspirant) Chase Products Co., Broadview, IL PRIST (Jet fuel additive) P.P.G. Industries, Inc., Pittsburgh, PA PRISTEEN (Deodorant) Warner-Lambert Co., Morris Plains, NJ PRIVATE AFFAIR (Cologne) Lenel Perfumes Inc., Dallas, TX PRO-CIDE (Insecticide) Virginia Chemicals, Inc., Portsmouth, VA PRO-COMFORT (Foot treatment products) Scholl, Inc., Memphis, TN PRODERM (Non-prescription drug) Dow B. Hickam, Inc., Houston, TX PRO-FIXX (Cytology fixative) Lerner Laboratories, New Haven, CT PRO KILL (Insecticide) Nationwide Chemical Products, Inc., Hamilton, OH PROMPT (Sunburn protectant) Chattem Drug & Chemical Co., Chattanooga, TN PROOF (Industrial and automotive product) Cerfact Laboratories, Tucker, GA PRO/PAK (Air freshener) Contact Industries, Inc., Elizabeth, NJ PRO SAN (Household products) Nationwide Chemical Products, Inc., Hamilton, OH PROTECTRA (Industrial product) J.I. Hol- comb Mfg. Co., Cleveland, OH PROTEXALL (Insecticides) Protexall Products, Inc., Longwood, FL PROCTOFOAM, (Pharmaceutical), Reed & Carnrick Pharmaceuticals, Kenilworth, NJ PULMORE (Farm product) Crown Industrial Products, Hebron, IL PURE AND SIMPLE (Food release coating) Follmer Development, Inc., Newbury Park, CA PURGE (Insecticide) Cline-Buckner, Inc., Cerritos, CA PURPLE LOTION (Livestock product) Dur- vet, Inc., Blue Springs, MO PURSE-POUF (Hair spray) Faberge, Inc., New York PURSUE (Disinfectant) Amway Corp., Ada, MI PYROIL (Automotive product) Pyroil Co., Albion, IL PYROLUBE (Industrial product) Kano Laboratories, Nashville, TN Q QDA (Athletic product) Cramer Products, Inc., Gardner, KS QUAKER, (Spray lubricant, penetrative oil, and automotive choke and carburetor cleaner), Quaker State Oil Refining Co., Oil City, PA QUATRASAN (Disinfectant) Amsco Medical Products, Erie, PA QUICK FREEZE (Anti-static) Miller-Stephenson Chemical Co., Danbury, CT QUICK FREEZE (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA QUICK PATCH (Roof and gutter repair product) Illinois Bronze Paint Co., Lake Zurich, IL QUIET PLEASE (Disinfectant deodorant) James Varley & Sons, Inc., St. Louis, MO QUIK (Housekeeping product) Kem Manufacturing Corp., Tucker, GA QUIKCIDE (Insecticide) Kem Manufacturing Corp., Tucker, GA QUIK-SPRAY (Stencil ink, silicone adhesive) Diagraph-Bradley Industries, Inc., Herrin, IL QUIK STICK (Spray-on adhesive) Maker Products, Inc., Irvington, NY R R-12 (Automotive products) CSA Limited, Inc., Houston, TX RAABE (Automotive and all-purpose spray paint) Raabe Paint Co., Inc., Wauwatosa, WI RAID (Insect control products) S.C. Johnson & Son, Inc., Racine, WI RAPID (Housekeeping product) Cerfact Laboratories, Tucker, GA
628 The Aerosol Handbook RAVE (Hair spray) Chesebrough-Ponds, Inc., Clinton, CT RAYDAR (Window cleaner) Cartier Chemicals, Ltd., Lachine, Quebec, Canada RCS (Insecticide) Colonial Products, Inc., Lake Worth, FL REAL CREAM (Whipped topping) Brough- ton Foods Co., Charleston, WV REAL-KILL (Household and lawn and garden pesticides) Realex Corp., Baton Rouge, LA RECO-KLEEN (Anti-static record spray) Workman Electronic Products, Inc., Sarasota, FL RED DEVIL (Paint) Red Devil Paints & Chemicals, Mount Vernon, NY REDDI-WHIP (Aerosol topping) Knudsen Corp., Los Angeles, CA REDDI WHIP (Whipped topping) Longlife Dairy Products, Jacksonville, FL REDDI-WIP (Cream and non-dairy toppings) Hunt-Wesson Refrigerated Foods, Fullerton, CA REEL LIFE (Lubricator and cleaner) Sportsmen's Labs, Inc., Anoka, MN REFECT FOAMY (Industrial and household) Bulk Chemicals, Gretna, LA RELEASAGEN (Industrial mold release agent) ReleasaGen Manufacturing Inc., Delano, MN RELEASE (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA REMOVE (Spot cleaner product) Amway Corp., Ada, MI RENUZIT (Air freshener) Drackett Co., Cincinnati, OH RESPOND (Analgesic foam) Respond Industries, Inc., Denver, CO RETARDD (Rust inhibitive primer, also finish coat) Benjamin Moore & Co., Newark, NJ REPEL (Insect repellent) Cartier Chemicals, Ltd., Lachine, Quebec, Canada RESIDEX (Industrial product) Kem Manufacturing Corp., Tucker, GA REVENESCENCE (Hair product) Lanvin- Charles of the Ritz, New York RICH PUFF (Hand cream) Fuller Brush Co., Great Bend, KS RIGHT GUARD (Deodorant) Gillette Co., St. Paul, MN RISE (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA RISE (Shave cream) Carter-Wallace, Inc., Cranbury, NJ RITE OFF (Grafitti remover cleaner) Rite Off Inc., Bayshore, NY RK (Hair spray) Redken Laboratories, Canoga Park, CA ROACH ROUTER (Insecticide) Orb Industries, Inc., Upland, PA ROD'S REAL CREAM (Aerosol topping) Knudsen Corp., Los Angeles, CA ROLMAR (Industrial freeze item) The Supply Corp., Lake Geneva, WI ROSE MILK (Skin care product) J.B. William Co., Inc., NY ROYAL SECRET (Cologne) Germaine Mon- teil Cosmetics, Deer Park, NY RUDD BRAND (Paint) Rudd Co., Seattle, WA RUS-KIL (Paint) Mobile Paint Manufacturing Co., Inc., Theodore, AL RUSTALOY (Paint) Fulton Chemical Co., Sumter, SC RUST COR (Paint) Illinois Bronze Paint Co., Lake Zurich, IL RUST FOIL, (Rust preventive), Knight Oil Corp., Johnstown, NY RUSTGUARD (Paint) Standard Brands Paint Co., Torrance, CA RUST GUARD (Paint) Precision Paint Corp., Adanta, GA RUST-MATE (Rust inhibiting spray paint) Zynolyte Products Co., Compton, CA RUST NAUGHT (Paint) Precision Paint Corp., Atlanta, GA RUST VETO (Rust preventive) E.F. Houghton & Co., Broomall, PA s SABRINA (Hair spray, After bath spray) Stanley Home Products, Inc., Westfield, MA SAFEGUARD (Insecticide, cleaner) Safeguard Chemical Corp., Bronx, NY SAIL (Household products) The Great Adantic & Pacific Co., Brockport, NY SALVASOL (Degreaser and solvent) Puritan/- Churchill Chemical Co., Adanta, GA SALVO (Insecticide) Sentry Chemical Co., Inc., Stone Mountain, GA SAMPLE (Stain spray) Fuller Brush Co., Great Bend, KS SANI MIST (Disinfectant, deodorant) Cartier Chemicals Ltd., Lachine, Quebec, Canada SANITIZED (Clothing and shoe deodorant) Sanitized, Inc., New York SANIWAX (Furniture polish and lemon oil) Berryman Products, Inc., Arlington, TX SAN-O-JET (Air deodorant) Rochester Midland, Rochester, NY SANTA (Aerosol snow, pine scent) Chase Products Co., Broadview, IL SATIN LEMON (Furniture polish) Cartier Chemicals Ltd., Lachine, Quebec, Canada SCARLET OIL (Livestock product) Durvet, Inc., Blue Springs, MO SCHICK (Shaving preparation) Warner-Lambert Co., Morris Plains, NJ SCHUCO (Medical spray products) Schuco, Wiliston Park, NY SCOTT'S LIQUID GOLD (Household product) Scott's Liquid Gold-Inc, Denver, CO SCOUNDREL (Perfumes and colognes) Rev- Ion, Inc., New York SCREW WORM (Insecticide) Pfizer, Inc., New York SCREW-WORM (Pharmaceutical) Durvet, Inc., Blue Springs, MO SCULPTURA (Cologne) Jovan, Inc., Chicago, IL SEAL-AID (Release agent) Orb Industries, Inc., Upland, PA SEAL-TITE (Stain and sealer) Behr Process Corp., Santa Ana, CA SECRET (Anti-perspirant/deodorant) Procter & Gamble, Cincinnati, OH SEE (Window cleaner) Madison Bionics, Franklin Park, IL SEE SPRAY (Lens and window cleaners) Amway Corp., Ada, MI SEEZ PRUF (Industrial and household) Bulk Chemicals, Gretna, LA SELECTRIC (Industrial product) Cerfact Laboratories, Tucker, GA SENSACORT (Personal product) Schering- Plough Corp., Memphis, TN SERCO (Refrigerants) Technical Chemical Co., Dallas, TX SENTRY-MINT (Disinfectant) Madison Bionics, Franklin Park, IL SEPTISOL (Hand sanitizer) Vestal Laboratories, St. Louis, MO SERGEANT'S SENTINEL (Insecticide) Miller-Morton Co., Richmond, VA SETTIT (Personal product) Fashion Two- Twenty, Inc., Aurora, OH 70 PSI (Dust Remover) Chemtronics, Inc., Hauppauge, NY SEYMOUR (Paint) Seymour of Sycamore, Inc., Seymour, IL SHARE (Paints, insecticides, industrial and automotive products) Share Corp. Milwaukee, WI SHEEN (Cosmetic) Duart Manufacturing Co., San Francisco, CA
Trademarks 629 SHIELD (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA SHOTGUN (Insecticide) Sentry Chemical Co., Inc., Stone Mountain, GA SHOT-KILL (Insecticide) Cerfact Laboratories, Tucker, GA SHOUT (Pre-spotter product) S.C. Johnson & Son, Inc., Racine, WI SHU-MAGIC (Leather refinishing product) Shirlo, Inc., Memphis, TN SHUR-START (Automotive product) Cerfact Laboratories, Tucker, GA SIL (Furniture polish) State Chemical Manufacturing Co., Cleveland, OH SILA-CERF (Industrial product) Cerfact Laboratories, Tucker, GA SIL-GLYDE (Industrial) American Grease Stick Co., Muskegon, MI SILICONE SPRAY, (Product for moving parts, pressroom equipment), Braznell Co., St. Louis, MO SILIFAX (Silicone lube) Madison Bionics, Franklin Park, IL SILKIENCE (Skin care products) Gillette Co., Boston, MA SILIKROIL (Industrial product) Kano Laboratories, Nashville, TN SILKOM (Hair lubricant) Roux Laboratories, Inc., Jacksonville, FL SILKON 35 (Silicone lubricant) Chemtronics, Inc., Hauppauge, NY SlLOO (Automotive products) American Parts Co., Inc., Houston, TX SKINNY DIP (Cologne) Leeming/Pacquin Division, New York SKRAM (Insect repellent) Conwood Corp., Memphis, TN S.L.C. (Paint) San Leandro Color, San Lean- dro, CA SLICK (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA SLIDE (Cleaning compounds and mold releases) Percy Harms Corp., Wheeling, IL SLIP-A-LUME (Aluminum lubricants) Contact Industries, Elizabeth, NJ SLIP-IT (Clear lube) Chem-Tech, Inc., Wilmington, DE SLIP SLIDE (Lubricant) Fabri-Coate Co., Inc., Grand Rapids, MI SLIP 'UM (Lubricant) Puritan/Churchill Chemical Co., Adanta, GA SLDC (Industrial coating) Kem Manufacturing Corp., Tucker, GA SLDC-IT (Lubricant) Crown Industrial Products Co., Hebron, IL SMOG OFF (Automotive, industrial) Darco Industries, Camp Hill, PA SNACKMATE (Food) Nabisco, Inc., Fair- lawn, NJ SNOOPY (Insecticides, products for birds, dogs and cats) Conagra Pet Products Co., Omaha, NE SO CLEAN (Household product) Bulk Chemicals, Gretna, LA SOFT 'N DRI (Antiperspirant/deodorant) Gillette Co., Boston, MA SOFT 'N GENTLE (Health and beauty aids) Penn Champ, Inc., East Buder, PA SOFT SOFT (Cologne) Vanda Beauty Counselor, Los Angeles, CA SOFTSOAP (Liquid soap prodcuts) Minne- tonka, Inc., Chaska, MN SOK (Insecticide) State Chemical Manufacturing Co., Cleveland, OH SOLARCAINE (First aid and sunburn treatment product) Schering-Plough Corp., Memphis, TN SOLV-CLEAN (Safety solvent cleaner) Chem- Pak, Inc., Winchester, VA SOLV-OFF (Solvent degreaser) Rochester Midland, Rochester, NY SOLV-O-MIST, (Dried ink cleaner), Braznell Co., St. Louis, MO SOOTSPRAY, (Soot remover), Stewart-Hall Chemical Corp., Mt. Vernon, NY SOPHIA (Fragrance) Coty Div., New York SOS (Glass cleaner) SOS Products Co., Inc., E. Greenville, PA SOURCE OF BEAUTY, Francis Denney, Inc., Philadelphia SOUTHERN COATINGS (Paint) Fulton Co., Sumten, SC SP-20 (Cleaner) Spartan Chemical Co., Toledo, OH SPARKLE PLENTY (Chandelier cleaner) Sparkle Plenty, Inc., Chicago, IL SPIN SPRAY (Industrial) Price-Driscoll Corp., Farmingdale, NY SPRA-DRI (Moisture displacer) Orb Industries, Inc., Upland, PA SPRA-DRI (Moisture displacer) Orb Industries, Inc., Upland, PA SPRA-LINE (Paint) Crown Industrial Products Co., Hebron, IL SPRA-SHINE (Housekeeping product) Cerfact Laboratories, Tucker, GA SPRA-TEMP (General purpose cleaner) DuBois Chemicals, Cincinnati, OH SPRA-TOOL (Spray device) Crown Industrial Products Co., Hebron, IL SPRAY-LAC (Industrial lacquer) Star Chemical Co., Inc., Hinsdale, IL SPRAY NINE, (Household cleaner), Knight Oil Corp., Johnstown, NY SPRAY NOX (Insecticide) Claire Manufacturing Co., Addison, IL SPRAY 'N VAC, (Carpet cleaner), Airwick Industries, Inc., Carlstadt, NJ SPRAY N WASH (Household product) Texize Chemicals Group, Greenville, SC SPRAY-O-MATIC (Industrial paints) National Aerosol Products Co., Los Angeles, CA SPRAY ON BANDAGE (Pharmaceutical) Zee Medical Products Co., Irvine, CA SPRUCE (Chemical) Seymour of Sycamore, Inc., Seymour, IL STA-FLO (Household products) A.E. Staley Products, Oakbrook, IL STA-LUBE (Lubricant) Sta-Lube, Inc., Compton, CA STANHOME (Household and industrial products, cosmetics, insecticides, personal products) Stanley Home Products, Inc., Easthampton, MA STAPHENE (Spray disinfectant) Vestal Laboratories, St. Louis, MO STAPOL (Housekeeping product) Kem Manufacturing Corp., Tucker, GA STARBAR (Insecticides, farm and ranch) Zoe- con Industries, Dallas, TX START (Automotive product) Sentry Chemical Co., Inc., Stone Mountain, GA STEEL-ONE (Metal cleaner) Madison Bionics, Franklin Park, IL STERIPHENE (Disinfectant spray) Spartan Chemical Co., Toledo, OH STETSON (Cologne) Coty Division, Sanford, NC STICK 'UM UP (Spray adhesive) Altawood, Inc., Gardena, CA STONER'S (Plastic mold releases) Stoner's Ink Co., QuarryvMe, PA STOP LOCK (Anti-seize compound) Chem- Pak, Inc., Winchester, VA STOP SQUEEK (Lubricant) Dri-Slide Inc., Fremont, MI STOVE BLACK (Paint) Illinois Bronze Paint Co., Lake Zurich, IL STRICTLY PERSONAL (Cologne) Lenel Perfumes Inc., Dallas, TX STRIKE (Insecticides) Zoecon Industries, Dallas, TX STRIPE (Paint) Seymour of Sycamore, Inc., Seymour, IL
630 The Aerosol Handbook STRIP-N-FLUSH (Industrial product) Kem Manufacturing Corp., Tucker, GA STRIPPER (Paint remover) Behr Process Corp., Santa Ana, CA STYLE (Hair spray) La Maur, Inc., Minneapolis, MN SUAVE (Cosmetic, personal products) Helene Curtis Industries, Inc., Chicago, IL SUDDEN BEAUTY (Hair spray) Whitehall Laboratories, Inc., New York SUNBRITE (Furniture polish) Rochester Midland, Rochester, NY SUPER (Spot remover) Fuller Brush Co., Great Bend, KS SUPER CLEAN SENTRY (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA SUPER FLAKE (Paint) California Custom Accessories Mfg. Co., Carson, CA SUPER FLO SPRAY (Dust mop treatment) Rochester Midland, Rochester, NY SUPER FOAM (Rug cleaner) Fuller Brush Co., Great Bend, KS SUPERSHEEN (Spray paint) Altawood, Inc., Gardena, CA SUPER SIL (Industrial product) Sentry Chemical Co., Inc., Stone Mountain, GA SUPER SPAR/CLEAR (Gloss and stain) Behr Process Corp., Santa Ana, CA SUPER WHIP (Cream toppings) Hunt- Wesson Refrigerated Foods, Fullerton, CA SUPER WISSH (Electronic cleaner) Workman Electronic Products Inc., Sarasota, FL SUPRASOAP (Waterless soap cleaner) Sparkle Plenty, Inc., Chicago, IL SURE (Antiperspirant) Proctor & Gamble Co., Cincinnati, OH SURF SPEED (Marine product) Sudbury Laboratory, Inc., Sudbury, MA SWEET EARTH (Cologne) Coty Division, Sanford, NC SWEET SHOT (Mouth refresher spray) Amway Corp., Ada, MI SWISS AIR (Industrial odor agent and insecticide) Steiner Co., Chicago, IL T TABU (Cosmetic) Dana Perfume Corp., New York TAMMY (Cosmetic) Old 97 Co., Tampa, FL TANA (Shoe care products) Tana Canada Inc., Montreal, Quebec, Canada TANGLEFOOT (Tree paint, residual insect spray) Tanglefoot Co., Grand Rapids, MI TANGLE-STRIP® (Insect trapping adhesive) Tanglefoot Co., Grand Rapids, MI TAPFREE (Metalworking fluid) Winfield Brooks Co., Inc., Woburn, MA TAP-TOOL (Spray device) Crown Industrial Products Co., Hebron, IL TARTAN (Paint) Rudd Co., Seattle, WA TASK (Disinfectant cleaner) Rochester Midland, Rochester, NY TATER TOP (Food) Instantwhip Foods, Inc., Columbus, OH TB-X (Institutional cleaner) Knight Oil Corp., Johnstown, NY T.D.L. (Industrial coating) Cerfact Laboratories, Tucker, GA TEFLEX (Mola release) Chemtronics, Inc., Hauppauge, NY TEN SIXTY-SIX (Weld anti-spatter) Chem- Pak, Inc., Winchester, VA TERM-OUT (Insecticide) Makiki Electronics, Hauula, Hawaii T.F.X. (Automotive and household products) Accra Pac, Inc., Elkhart, IN THURMALOX (Paint) Dampney Co., Everett, MA TICK-TOX (Insecticide) Orb Industries, Inc., Upland, PA TILE 'N GROUT MAGIC (Foam cleaner) Magic American Chemical Corp., Cleveland, OH TIMBERLINE, (Cologne), Mem Co., Inc., Northvale, NJ TIME BOMB (Insecticide) Colonial Products, Inc., Lake Worth, FL TING (Pharmaceutical) Pennwalt Corp., Rochester, NY TITE GRIP (Belt dressing) Berryman Products, Inc., Arlington, TX TONE (Musical instrument accessories) Chem-Pak Inc., Winchester, VA T.O.P. (Lubricant) DuBois Chemicals, Cincinnati, OH TOPPEROO (Ice cream topping) Best Foods Division, CPC International, Englewood Cliffs, NJ TOPPIT (Personal product) Fashion Two Twenty, Inc., Aurora, OH TOP WIP (Dairy product) Knudsen Corp., Los Angeles, CA TOUCH-N-FOAM (Home insulation products) Convenience Products, St. Louis, MO TOUCH 'N STICK (Adhesive) Convenience Products, Inc., St. Louis, MO TOUCH OF CLASS (Cologne) Faberge, Inc., New York TOUCH OF SCENT (Household product) Scott's Liquid Gold, Inc., Denver, CO TOUCH-UP (Disinfectant cleaner) Madison Bionics, Franklin Park, IL TOUGH AS TILE (Paint) New York Bronze Powder Co., Inc., Elizabeth, NJ TRAC II (Shaving cream) Gillette Canada, Inc., Montreal, Quebec, Canada TRALA (Personal product) Colonial Dames Co., Commerce, CA TRANSI-LUBE (Personal lubricant) Holland- Rantos Co., Inc., Trenton, NJ TRI-CHEM (Industrial and insecticide products) Tri-City Chemical Corp., Nashua, NH TRIPLE TOOL (Lubricant, penetrant and rust preventive) Chem-Pak, Inc., Winchester, VA TRUE BLUE (Spotting and fitting blue) Chem-Pak, Inc., Winchester, VA TRUE SCRIBE (Layout ink) Chem-Pak, Inc., Winchester, VA TRU-NOX (Insecticide) Sprayway, Inc., Addison, IL TRU-TEST (Paint) Cotter & Co., Chicago, IL TSI (Lubricants) American Gas & Chemical, Northvale, NJ TUFF SPOT (Housekeeping product) Kem Manufacturing Corp., Tucker, GA TUFF STUFF (Foam cleaner) Union Carbide Corp., Home and Automotive Products Div., New York TUF-SKIN (Athletic product) Cramer Products, Inc., Gardner, KS TUNER-RENU (Tuner cleaner) Chemtronics, Inc., Hauppauge, NY TUN-O-POWER (Lubricant, cleaner) Chemtronics, Inc., Hauppauge, NY TUN-O-WASH (Tuner degreaser) Chemtronics, Inc., Hauppauge, NY TURGASEPT (Pharmaceutical) Ayerst Laboratories, Inc., Rouses Point, NY TURTLE WAX (Automotive products) Turtle Wax, Inc., Chicago, IL TUSSY (Toiletry) Lehn & Fink Products Group, Montvale, NJ 20 CARATS (Cologne) Dana Perfume Corp., New York 2000° STA-FREE (Industrial and automotive product) Cerfact Laboratories, Tucker, GA u ULTRA BAN (Antiperspirant) Bristol Myers Co., New York ULTRA WISSH (Electronic cleaner) Workman Electronic Products Inc., Sarasota, FL
Trademarks 631 ULTROSOL (Pharmaceutical) Pascal Co., Inc., Bellevue, WA UNGUENTINE (Pharmaceutical) Norwich- Eaton Pharmaceuticals, Norwich, NY UTILAC (Spray paint) Benjamin Moore & Co., Newark, NJ V VALSPAR (Enamel paint) Valspar Corp., Minneapolis, MN VALUE PLUS (Household and personal products) Chase Products Co., Broadview, IL VANDAL VANISH (Housekeeping product) Kem Manufacturing Corp., Tucker, GA VANDAL-X (Graffiti remover) Contact Industries, Elizabeth, NJ VANGARD (Shoe care products) Vangard Chemical Corp., St. Louis, MO VAPASEPTIC (Disinfectant/deodorant) Air Shields Division, Hatboro, PA VAPORETTE (Insecticides, household) Zoe- con Industries, Dallas, TX VARCO RESISTANT ROACH SPRAY (Insecticide) James Varley & Sons, Inc., St. Louis, MO VARI-TONE (Haircolor) Roux Laboratories, Inc., Jacksonville, FL VARSEPTIC (Disinfectant cleaner) James Varley & Sons, Inc., St. Louis, MO VELVET (Furniture polish) Avmor Ltd., Montreal, Canada VESTALIA (Cologne) Lenel Perfumes Inc., Dallas, TX VET KEM (Insecticides, veterinary) Zoecon Industries, Dallas, TX VIGILANTE (Industrial and institutional housekeeping product) Kem Manufacturing Corp., Tucker, GA VINYL MAGIC (Cleaner) Magic American Chemical Corp., Cleveland, OH VIRCHEM (Insecticides) Virginia Chemicals, Inc., Portsmouth, VA VIRMIST (Insecticide) Virginia Chemicals, Inc., Portsmouth, VA VIRO-CERF (Housekeeping product) Cerfact Laboratories, Tucker, GA VIRO-TEC (Disinfectant) American Hospitex Corp., Decatur, GA VIT (Industrial lubricants) Cartier Chemicals, Ltd., Lachine, Quebec, Canada VITALIFE (Wire rope dressings) American Oil & Supply Co., Newark, NJ VITSOL 95 (Industrial solvent) Cartier Chemicals, Ltd., Lachine, Quebec, Canada VIT SS (Stainless steel cleaner) Cartier Chemicals, Ltd., Lachine, Quebec, Canada VO-5 (Hair spray) Alberto-Culver Co., Melrose Park, IL VOLTEX (Industrial and paint products) Makiki Electronics, Hauula, Hawaii VYRASEPT (Disinfectant) Puritan/Churchill Chemical Co., Atlanta, GA w WARD OFF (Household product) Bulk Chemicals, Gretna, LA WAG (Lubricant spray) State Chemical Co., Cleveland, OH WAS (Insecticide) State Chemical Manufacturing Co., Cleveland, OH WASP GUN N7 (Insecticide) Bulk Chemicals, Gretna, LA WASP-NOT, (Insecticide), Nott Manufacturing Co., Inc., Pleasant Valley, NY WATER GARD (Rust preventive) Chem Pak, Inc., Winchester, VA WATER SHIELD (Rust preventive) Chem- Pak, Inc., Winchester, VA WAYS EASE (Machine lubricant) Chem-Pak, Inc., Winchester, VA WEATHERPRUF (Industrial product) Kano Laboratories, Nashville, TN WEATHERSHED (Rust preventive) E.F. Houghton & Co., Broomall, PA WEEKEND (Paint) Illinois Bronze Paint Co., Lake Zurich, IL WEP (Moisture displacer and rust remover) Workman Electronic Products Inc., Sarasota, FL WET PAINT (Paint) Illinois Bronze Paint Co., Lake Zurich, IL WHISKER WHIZ (Shaving cream) Amway Corp., Ada, MI WHITE GREASE (Industrial degreaser) J.I. Holcomb Mfg. Co., Cleveland, OH WHITE MINK (Personal product) Duart Manufacturing Co., San Francisco, CA WHITE RAIN (Hair spray) Gillette Co., St. Paul, MN WINDDRIFT, (Cosmetic), Mem Co., Inc., Northvale, NJ WINDEX (Window cleaner) Drackett Co., Cincinnati, OH WINDO-GLO (Glass cleaner) Rochester Midland, Rochester, NY WINKOTE (Garden product) Sudbury Laboratory, Inc., Sudbury, MA WINTER VU (Automotive) The Barcolene Company, Holbrook, MA WISSH (Electronic contact cleaner) Workman Electronic Products Inc., Sarasota, FL WONDER COAT, Tech Spray, Inc., Ama- rillo, TX WONDER MASK (Industrial product) Tech Spray, Inc., Amarillo, TX WONDER MIST (Lubricant and rust inhibitor) Amway Corp., Ada, MI WOODCRAFTER (Furniture polish) Colgate-Palmolive Co., New York WOODSMAN (Stain) General Paint & Chemical Co., Cary, IL WOUND PROTECTOR (Insecticide) Ralston Purina Co., St. Louis, MO X X-E-CUTE (Insecticide) DuBois Chemicals, Cincinnati, OH X-SEIZE 2000 (Industrial and automotive products) Kem Manufacturing Corp., Tucker, GA X-O RUST (Paint) General Paint & Chemical Co., Cary, IL X-TERM (Insecticide) Contact Industries, Elizabeth, NJ Y YANKEE LABEL (Whipped cream) Agri- Mark, Inc., Newington, CT YDP LICE SPRAY (Insecticide) Holland- Rantos Co., Inc., Trenton, NJ YOUNG & FIRM (Personal product) Duart Manufacturing Co., San Francisco, CA z ZAP (Insecticide) Sentry Chemical Co., Inc., Stone Mountain, GA ZAPPER (Personal protection product) Safety & Security Co., Harleysville, PA ZEP (Industrial, automotive, insecticide and institutional products) Zep Manufacturing Co., Atlanta, GA ZERO (Contact point cleaner) Chem-Pak, Inc., Winchester, VA ZINC-COAT (Industrial coating) Cerfact Laboratories, Tucker, GA ZINSSER (Paint) Cook Paint and Varnish Co., North Kansas City, MO ZIPP, (Degreaser), Stewart-Hall Chemical Corp., Mt. Vernon, NY ZODIAC (Insecticides) Zoecon Industries, Dallas, TX ZOTOS (Cosmetics) Zotos International, Inc., Darien, CT ZURD (Pest control chemicals) Murd Co., Philadelphia, PA
632 The Aerosol Handbook GLOSSARY OF TERMS USED IN THE AEROSOL INDUSTRY Active Ingredient - component of an aerosol formulation that produces the specific effect for which the formulation is designed. Aerosol Packaging - pressurizing sealed containers with liquified or compressed gases so that the product is self dispensing. The term aerosol as used here is not confined to the scientific definition; i.e., a suspension of fine solid or liquid particles in air or gas. Aspirator Valve Propellant vapor is aspirated through an orifice in Ihe valve chamber, causing a suction effect which draws product up the diptube and into the valve. Auxiliary Solvent - liquid material used in addition to the primary solvent. Generally used to replace part of the primary solvent to produce some specific effect or as a matter of economics. Chemical Attack - chemical reaction or solvent effect, causing failure or deterioration of plastic and rubber parts, organic coatings, metals, or lithography involved in the completed package. Co-Dispensing Valve - arrangement whereby two components of a product are separated inside the container and mixed at the time of use when ejected through dual channels into the valve. Cold Filling - pressurizing a container by cooling the propellant (and sometimes the product) below its boiling point and transferring into the container before the valve is put in place. The operation is usually used where propellant content is large and is carried out at atmospheric pressure; i.e., high pressure equipment is not needed. Compatibility - broad term meaning that the various components of an aerosol formulation can be used together without undesirable physical or chemical results. Concentrate - the product mix to which propellant is added. Cosolvent - solvent used to improve the mutual solubility of other ingredients. Crimp - an operation by which the valve is mechanically sealed to the container. Density - weight of a given volume of material at a specified temperature. Delivery Rate - weight of mixture discharged from dispenser per unit of time at a specified temperature. Usually expressed as grams/-second at 80°F. Dip Tube - tubing connecting the lower portion of container or dispenser with valve. Head Space - volume in upper portion of dispenser not filled with liquid contents. Usually expressed as percent of total volume of dispenser at a specified temperature. Inert (or Inactive) Ingredient Component of an aerosol formulation that does not contribute to the specific effect of the formulation. In some cases, may be quite arbitrarily defined. 1 or example, with insecticides, only the propellants are considered as inert ingredients. Metering Valve valve that delivers a definite, limited amount of aerosol formulation each time the valve mechanism is operated. Nonvolatile Ingredient - components of an aerosol formulation with a vapor pressure less than atmospheric pressure (< 14.7 Ibs/sq in absolute) at a temperature of I05°l . Official Test Aerosol, or OTA a standard insecticide dispenser and formulation prepared hy CSMA for use in Official Aerosol lest Methods for flying Insects. Particle Size diameter of solid or liquid particles expressed in microns (thousandths of a millimeter). Pressure - internal force per unit area exerted by any material. Since the pressure is directly dependent on the temperature, the latter must be specified. The pressure may be reported in either of two ways: a. Absolute pressure - the total pressure with zero as a reference point. Usually expressed as pounds per square inch absolute (psia). b. Gage pressure - the pressure in excess of atmospheric pressure. Under standard conditions at sea level, the numerical value of the absolute pressure is 14.7 higher than that of the gage pressure. The gage pressure is usually expressed as pounds per square inch gage (psig). Pressure Filling - pressurizing a container by injecting propellant through the valve under high pressure. The operation is usually used where the propellant content is small and is carried out under ambient conditions; i.e., refrigeration equipment is not needed. Product Deterioration - chemical reaction or physical change within or between components considered compatible in original formulation. May be due to time or temperature of storage or other factors. Product Formulation - specific formulation of completed product, including propel- lant(s). Usually expressed as weight/ weight (w/w) percent. Propellant - liquified gas with a vapor pressure greater than atmospheric pressure (14.7 lbs/sq in absolute) at a temperature of 105°l\ Solubility - the extent to which one material will dissolve in another. Generally expressed as percent by weight. May also be expressed as percent by volume or parts per 100 parts of solvent by weight or volume. The temperature should be specified. Solvent - liquid part of an aerosol formulation used to dissolve solid or other liquid parts. Spray - the dispersed discharge from an aerosol-type dispenser in the form of small droplets or particles. Does not include foam-type discharge. Spray Coating - aerosol spray product for surface application, which leaves a residual clear or pigmented finish for protective or decorative purposes. Storage Stability - ability of a product to maintain its original characteristics over extended storage periods, under normal variations in temperature conditions. Synergist - an auxiliary material that has the property of increasing the effect of the active ingredient even though it may have little specific activity itself. NOTE: In the case of insecticides, synergists are considered as active ingredients. Three-Phase System - a vapor phase and two liquid phases, one of which is usually the propellant inside the container. Two-Phase System - a vapor phase and a single liquid phase, usually containing dissolved propellant, inside the container. Under the Cap Filling - a process for adding propellant to the container by sealing off the head of the container and injecting propellant at ambient temperature and high pressure, under the valve cap before crimping. The process is usually used where the propellant content is large and cold filling is not desired. Valve - mechanism for discharging products from aerosol-type dispensers. Viscosity - internal resistance to flow of a solid (powder), liquid or gas at a specified temperature. A definite measurement for the consistency of a material. Volatile Ingredients - components of an aerosol formulation with a vapor pressure greater than atmospheric pressure (=• 14.7 Ibs/sq in absolute) at a temperature of 105°F.
633 A — Aerosol Grade of hydrocarbon propellents. Designation is followed by pressure at 70°F; as "A31," for Aerosol Grade Isobutane. Also applies to mixtures of Aerosol Grade Propane/Isobutane. The purity is generally better than 95 mol% and product is low in odor. A-C617 — Polyethylene emulsion used in sunscreen products. Allied Chemical Corp. ACC — American Can Co. ACMI — American Can Maker's Institute. Sometimes called CMI. ADR — Accord European Relatif le Transport International Dangereuses par Route. AQL — Acceptable quality level. ARCTON—Fluorocarbon propellent. Imperial Chemical Industries, Great Britain. ARLACEL — Line of non-ionic surfactants. ICI America, Inc. ASME — American Society of Mechanical Engineers. ASTM — American Society for Testing Materials. valves. Resistant to aliphatics, but expands and weakens in contact with moderate concentrations of chlorinated solvents. CAA — Clean Air Act of 1977. CANCO — American Can Co. CANMAKER'S SOLDER — Common side seam solder of about 2.5% tin and 97.5% lead. CCC — Continental Can Co. INDUSTRY TRADE TERMS AND ABBREVIATIONS AEROCEUTICAL — Aerosol pharmaceutical. AERON® — Gas liquid. Diversified Chemicals and Propellents Co. AEROSOL GUIDE — Publication of the Chemical Specialties Manufacturers Association listing aerosol test methods. AEROSEAL M22 — Hose clamp. AEROTHENES — Solvents used in aerosols made by Dow Chemical U.S.A. (Aero- thene MM - a specially inhibited methylene chloride. Aerothene TT - a specially inhibited 1, 1, 1 - trichloroethane. AF&TD — Alcohol, Firearms & Tobacco Division. U.S. Treasury Dept. AIDS — Aerosol Industry Development Society. AMP — Aminomethylpropanediol. AMPHOMER — Resin for hairspray. National Starch & Chemical Co. AMPHOSET — Terpolymer hair spray resin. Penick Corp. AOAC — Association of Official Agricultural Chemists. AOQ,— Average outgoing quality. APACHECAN — Aluminum container. Made from 1967-1981. API — American Petroleum Institute. This list of abbreviations and terms is confined to those used in The Aerosol Handbook. It is not intended to be a complete list of trade terms. B BAMA — British Aerosol Manufacturers Association. BAREX — A compound of about 80% copolymer of acrylonitrile and methyl acrylate plus about 20% butyl rubber matrix component, used to make plastic aerosols. Union Carbide Corp. BASELOCK — A method for holding rubber letters and type by the base, using a mortised joint into a rubber base pad. A system commonly used in coding machines for holding type. BCME — Bichloromethyl ether. BHT — Antioxidant. Butylated hydroxy- toluene. BOD — Biological oxygen demand. Term used in wastewater analysis. BOF — Basic oxygen furnace. BRB — British Railways Board. BUNA — Copolymer of styrene and butadiene used as a gasket material for aerosol C/CO PLATE — Chrome/chrome oxide steel. CELCON — Highly crystalline acetal copolymer based on trioxane. Celanese Corp. CFA — Comite Francais des Aerosols. Paris, France. CFC — Chlorofluorocarbon. CGMP — Current good manufacturing practices. CHILDGARD — Child resistant closures. Sunbeam Plastics Corp. CMI — Same as ACMI, American Can Maker's Institute. COD — Chemical oxygen demand. Term used in wastewater analysis. COLIPA — Comite de Liason des Syndicates Europeen de l'lndustrie de la Perfumerie et des Cosmetiques. Brussels, Belgium. CONOLOY — Plastic for use in making bags used in compartmented aerosols. Continental Can Co.
634 The Aerosol Handbook CONOWELD — Metal container with welded side seam. Continental Can Co. CPSC — Consumer Product Safety Commission. 2CR PLATE — Twice cold rolled plate. CSMA — Chemical Specialties Manufacturers Association, Suite 1120, 1001 Connecticut Ave. NW, Washington, DC, 20036. CTFA — Cosmetics Toiletries & Fragrances Association. Formerly TGA. CTS — Chemically treated steel. D D-28 — Enamel lining on aluminum cans. Nomenclature used by American Can Co. D & A — Dewey & Almy Div., W.R. Grace & Co. Manufacturer of gasketing compounds. DAREX CAP 48 — Natural latex gasket material. Dewey & Almy Div., W.R. Grace & Co. DART GASSER "Hypodermic needle" gasser developed by Sterigard Corp. for gassing the ' 'Powr-Flo" dispenser made by American Can Co. DAY-GLO — Special can colors. D & C — Classification of coal tar dyes approved by FDA for use in drugs and cosmetics. DDVP — 2,2-Dichlorovinyl dimethyl phosphate. (Vapona) Shell Chemical Co. DEET — N, N-diethyl-m-toluamide. Active ingredient of aerosol insect repellents. DERLIN — Acetyl plastic used for some aerosol valve components. E. I. du Pont de Nemours & Co. D & I — Drawn and ironed. (Cans) DIMENSIONS "A" THROUGH "G" — Dimensions of an aerosol can. DL-MENTHOL — 3-Hydroxy-p-men- thane. Used to simulate cooling effect on skin. DME — Dimethylether. (Propellent) DOE — Department of Energy. DOT — Department of Transportation. DR — Double reduced plate, with reference to can thickness. DRIERITE — An absorbent. Fisher & Porter Co. DYNA-MIST — Break-up system. Sea- quist Valve Co. DYNA VAIR — Pressurized container and dispensing apparatus. Ciba-Geigy Corp. £ E3 and E4 — Plastic bags made of a core of Saran-coated nylon with overlaps of du Pont Seralyn on both sides. Bags are used in "Powr-Flo" containers. E5 — Single coat system on aerosol cans. American Can Co. ECCS — Electrolytic chrome coated steel. EEC — European Economic Community. ELECTROCEL — Process using transfers for decorating glass bottles. ELECTRO-HYDRAULIC CAN FORMING PROCESS — Can manufacturing procedure developed by Continental Can Co. (Not used commercially). EMSEAL — Flowed-in 20mm gasket. Emson Research Inc. EPA — Environmental Protection Agency. EPON (Or EPOXY) — Enamel lining often used as base coat for aerosol cans. Prepared as a hybrid, usually with phenolics. ETP — Electrolytic tinplate. EXACTA-MIST — Actuator button. Emson Research Inc. EXCEL 100 — Actuator button. Seaquist Valve Co. EXXEL — Barrier pack unit. Container Industries Inc. F FDA — Food and Drug Administration. FDCA — Food, Drug and Cosmetic Act. FEA — Federation of European Aerosol Associations. FEPCA — Federal Environmental Pest Control Act of 1971. FHSA — Federal Hazardous Substances Act of 1961. FIFO — First in/first out. FIFRA — Federal Insecticide, Fungicide and Rodenticide Act of 1947. FITZALL VALVE — Can puncturing valve. FLIP — Formed liner in place. FLO-MASTER — Tinplate container. (A piston can). Introduced in 1969, now discontinued. American Can Co. FORANE — Fluorocarbon propellents. Societe des Usines Chimiques Ugine Kuhlmann, Paris, France. FORWARD LOOK BUTTON — Sharp pointed actuator. Seaquist Valve Co. FP — Food propellent. FP — Food purity grade. (Applied to hydrocarbon propellents). FP-108 — Food purity propane. FPLA — Fair Packaging and Labeling Act. FREON — Fluorocarbon propellents. E. I. du Pont de Nemours & Co. Inc. FRIGEN — Fluorocarbon propellents. Farbwerke Hoechst, Frankfort, Germany. FTC — Federal Trade Commission. FTP A — Federal Trade Practices Agency. G GAF — General Aniline & Film Corp. GATT — General Agreement on Tariffs and Trades Section.
Trade Terms 635 G DIMENSION — CSMA dimension for can curl thickness. GENETRON — Non-flammable fluoro- carbon propellents. Allied Chemical Corp. GIBSON GIRL — Hourglass shaped aerosol container. GK-45-NVH and GK-45-NV—Neoprene based flowed-in gasket for aerosol valves. Dewey & Almy Div., W.R. Grace & Co. GLAMINATE — Laminate of polyethylene/aluminum/polyethylene used by American Can Co. in making plastic bags for use in compartmented aerosol containers. GLC — Gas/liquid chromatograph. GMP — Good manufacturing practices. (Same as CGMP). GRAS — Generally regarded as safe. GUZZI — Machine for necking-in aluminum containers. H HI-TEX — Textured can design. Continental Can Co. HLB — Hydrophilic/lypophilic balance. A term used to describe the emulsifying action of non-ionic detergents. IATA — International Air Transport Association. ICC — Interstate Commerce Commission. Most of its functions now assumed by DOT. IGA — Interessen-Germeinschaft Aerosole e.V. German Aerosol Association. IMCO — Intergovernmental Maritime Consultive Organization. IMDG — International Maritime Dangerous Goods, (code) INNOVAIR — Aerosol dispenser in which propellent is enclosed in a separate cartridge. Ciba-Geigy Corp. IRGASAN DP-300 — Bacteriostat similar in action to hexachlorophene. 2-Hydroxy- 2 '4,4 '-trichlorodiphenyl oxide. Ciba-Geigy Corp. IRLG — Interagency Regulatory Liason Group. ISO — International Standards Organization. Paris, France. ISOTRON — Propellent line. Pennwalt Corp. ITO — Trade name for insecticide packed in Europe in an Innovair container. K K-5 — Double lining system for cans. American Can Co. KANG — Compartmented aerosol. Interior bag is of aluminum foil. Societe Valois, France. K B VALUE — Kauri Butanol Value. Solvent valuation of a propellent. KN-211 — Mounting cup designation. Aerosol Research Co. (Normally for their internal use). KROPLIN S-2002 — Gauge for measuring height of can bead. M LAMI/SOL — Aerosol coating. Wheaton Plastic-Cote Corp. LANOL — Lanolin derivative LEKTRASET — Process for decorating glass bottles. LEL — Lower explosive limit. LIDOCAINE — Potent local anesthetic. Same as xylocaine. 2-(Dimethyl-amino-2 ', 6 '-acetoxylidide). LOP AC — Brittle copolymer of acrylon- itrile and styrene. Monsanto Co. LPG — Liquid petroleum gas. L-STEEL — Steel containing maximum of 0.06% copper. LUCHAIRE-FINANCES — Refers to an apparatus used in Europe for determining higher temperature flashpoints. MAC — Toxicity rating. (Maximum allowable concentration). MACROSPHERICAL — Aluminum chlorohydrate antiperspirant. Reheis Chemical Co., Berkeley Heights, NJ. MBU — Mechanical break-up systems, referring to valve actuator function. MDI — Methylene diisocyanate. MEYERCORD — Process using decals to decorate glass bottles. MGK-264 — N-octyl bicyclo heptene dicarboximide. MGK Co. MICROFRAGRANCE — System of microencapsulation of fragrances. 3M Co. MICROMAT — Aerosol filling equipment. Pamasol, Switzerland. MICRON 5 — Tunnel type of oral actuator. Societe Valois, France. MIRA-FLO — Aluminum container containing a plastic piston and pierced base section. American Can Co. MINISOL — Aluminum can by St. Gobain, Ltd. Distributed in U.S.A. by Pelorex Corp. MIRA-MIN — Aluminum can. American Can Co. (obsolete) MIRA-SEAM — Can with cemented side seam, no longer in production. American Can Co. MIRA-SPRA — Aluminum can. American Can Co. MONOBLOC — Manufacturing process for one-piece aluminum cans. MR-STEEL — Minimum residual plate. An alloy from which most aerosol cans are fabricated. MSA MODEL EXPLOSIMETER — Equipment used to detect hazardous concentrations of hydrocarbon gases in air. Mine Safety Appliances Co. MULLEN TEST BURSTING STRENGTH — Test applied to corrugate as a measure of resistance to loads. MYLAR — Low permeability plastic.
636 The Aerosol Handbook N NAM — Original name of "Selvac" container. NBS — National Bureau of Standards. (Parent organization of the Office of Weights & Measures.) NCC — National Can Corp. NCPS — National Commission on Product Safety. NDA — New drug application. NDR — European Trucking Association. NEISS — National Electronic Injury Surveillance System. Started in July 1969 under HEW, and transferred to the Consumer Product Safety Commission. NEOPRENE — Synthetic rubber composed principally of chains of 1,4-poly- chloroprene cross-linked by vulcanization. Resistant to chlorinated solvents, but has poor compatibility with aromatics. Available in different hardnesses. (Durometers). NFPA — National Fire Protection Association. Batterymarch Park, Quincy, MA. NICHOLSON VALVE — Bottom charging valve developed for use in gassing Sepro cans. NIELSEN — Applies to TV ratings, indicating number of persons having their sets turned on to receive a specific program. Ratings made by Nielsen, Inc. 1290 Ave. of the Americas, New York. NITROSOL — Nitrogen propelled aerosol. o OC — Operating characteristics. OPET — Biaxially oriented polyethylene terephthalate. ORGANOSOL — Sprayed-on vinyl topcoat lining for aerosol cans. Usually applied to tinplate cans for superior protection. ORM-D — Otherwise Regulated Material, Class D. OSHA — Occupational Safety and Health Act of 1970. OTA — Official test aerosol. Standard insecticidal aerosol formulation used as a control in making evaluations of insecticidal potency. OTC — Over the counter. P PABA — Parabenzenes. PANAMA SEAMER — Machine used in closing double seam cans. PEERASOL — Aluminum container. Peerless Tube Co. PEL — Permissible exposure limit. PENSKY-MARTINS — Refers to an apparatus for measurement of higher temperature flashpoints. PEPO — Piston can used in 1969. S.A. Kervil, N.V., Brussels, Belgium. PERT — Program evaluation review technique. A decision making tool, linking together activities and events related to the decision making process. Used in production planning, advertising and marketing programs, product introductions, etc. PL — Private label products. PLASTISOL — Plastic applied in viscous or melted form, as in the manufacture of plastic coated glass aerosol bottles. PMMI — Packaging Machinery Manufacturers Institute. Washington DC. POLYMERIZATION GRADE — Grade of propylene with 99.0 mol% minimum purity. POP-LOK — Plastic childproof closure. Safety Packaging Corp. PPA — Poison Prevention Act. PPPA — Poison Prevention Packaging Act of 1970. PRESSUREMASTER—Two-piece 211 x 413 can. American Can Co. (obsolete) PREVAL — Aerosol dispenser in which propellent is in a separate cartridge. Precision Valve Corp. PRE-VENT — Tailpiece filtration system developed by Precision Valve Corp. PRM — Pressure relief mechanism. A dome of can. PURSTIN — Purse-size tin plated aerosol container. Emson Research Inc. PVA — Polyvinyl acetate. PVC — Polyvinyl chloride. PVP — Polyvinylpyrollidone. R RANSBURG ELECTROSTATIC SPRAY SYSTEM — System used in application of an exterior coating to aluminum cans. RAR — Applies to tamperproof seal and a line of aerosol actuators. RCRA — Resource Conservation and Recovery Act. RIBAND STEEL — Steel plate. U.S. Steel. RID — European Railroad Association. Reglement International Concernant le Transport de Merchandise Dangereuses par Chemin de Fer. ROI — Return on investment. RQL — Rejectable quality level. RT — Room temperature. RVR — Rim vent release. A pressure-activated safety feature for aerosol cans. American Can Co. s SAMI — Selling Areas Marketing, Inc. A marketing research organization. 1290 Ave. of the Americas, New York. SATA — Southern Aerosol Technical Association, formed in 8/81. Atlanta homebase, no permanent address. SCC — Southern Can Co. SCC — Society of Cosmetic Chemists. "S" CURVE — Locus of points, plotting sales vs advertising, showing the rate of change of the impact of advertising outlay on sales. Also, graph of sales volume vs
Trade Terms years, showing degree of market maturity for new products or industries. SEA FOAM — Aerosol valve assembly with foam actuator. Seaquist Valve Co. SEA MIST — Aerosol valve assembly with mechanical break-up action. Seaquist Valve Co. SEA SPRAY — Valve series. Seaquist Valve Co. SEFEL — Society for European Container Standards. SELVAC — Self evacuating container which derives dispensing pressure from contraction of a resilient bladder. Originally called the NAM Container. Plant Industries, Inc. SEPRO CAN — Compartmented container. Continental Can Co. SERALYN A — Plastic component of bags used in certain compartmented aerosols. SG&A — Selling, general and administrative expense. SILVERGLO — Decorative can finish. SKU — Shelf space rating. SNAP-LOX — Tamperproof closure. Newman Green, Inc. SNG — Synthetic natural gas. SORBO — Sorbitol, a hexahydric alcohol. ICI America, Inc. SPF — Skin protection factor. SPITZER PATENT — Patent granted to George Spitzer et al, covering the manufacture of shaving cream, involving use of fluorocarbon propellents. SPRA-GUIDE — Directional control actuator cap. Seaquist Valve Co. SPRA-MATE — Directional control overcap actuator. Seaquist Valve Co. SPRA-TAINER — Two-piece tinplate cans. Crown Cork & Seal Co. SR — Single reduced plate. SSS — Side seam striped cans. A special band of inside enamel is sprayed over the side seam joint to protect it from attack by the products. STARWHEEL — Actuating device for counting cans, centering cans in position for filling or gassing, etc. STEL — Short term exposure limit. SOUDRONIC PROCESS — Process for making welded side seam cans. SWDA — Solid Waste Disposal Act. T T-56 — Plastic tilt action valve. Aerosol Research Co. TBA — Tertiary butyl alcohol. TC-42 — Gray organosol can lining. American Can Co. TCC — Tagliabue closed cup. Flashpoint tester. TFS — Tin free steel. TGA — Toilet Goods Association. Renamed the Cosmetics, Toiletries and Fragrances Association, CT&FA. THERIMAGE — Circular transfer labels used on plastic containers. TIP SEAL — Term assigned to family of tip-sealing valves. TLV — Threshold limit value. TOC — Tagliabue Open Cup flashpoint tester. TOYA-SEAM — Cemented side-seam can made in Japan. TRG — Technical regulations for pressurized gases. TRICOM SOLDER — Ordinary can maker's solder to which has been added 0.5% silver. Also called HS-5 solder. TSCA — Toxic Substances Control Act of 1972. TWA — Time weighted average. TWIST LOCK — Two-piece directional actuator. Emson Research, Inc. TYPE MR — Minimum residuals. 637 U UCON — Fluorocarbon propellents. Union Carbide Corp. (obsolete) UL — Underwriter's Laboratories Inc. UNIFORM COMMERCIAL CODE — Laws governing routine business practices. USP — U.S. Pharmacopia. U-t-C — Under-the-Cap method of aerosol filling. Kartridg Pak Co. V VANCIDES — Line of Bacteriostats. R.T. Vanderbilt Co. VARNLEY VALVE — Experimental bottom gassing valve tested by American Can Co. for gassing Mira- Flo containers but rejected in favor of pushing a rubber plug through a hole in can bottom, then gassing with a syringe. VC — Vinyl chloride. w WACO CONDUCTIVITY TESTER — Unit for checking sprayed-on can linings. WAIB — Western Aerosol Information Bureau. Formed in 1974. WHO — World Health Organization. WIFAG PRINTER — Unit for decorating lacquered aluminum containers. X,Y X-28 — Double coating on cans. American Can Co. YEOMAN'S METHOD — Testing method for determining aerosol particle size. See CSMA Aerosol Guide 7th Edition, 1981. z ZAHM & NAGEL APPARATUS — Device for determining air content in aerosol cans. Used on carbon dioxide packs only. ZYTEL — Nylon tube polyamide plastic. E.I. du Pont de Nemours & Co.
638 The Aerosol Handbook Company Listings The following companies are mentioned in The Aerosol Handbook. Addresses are supplied to make it easier for readers to locate them. This is obviously not a complete listing of industry suppliers, and is not so intended. ADVANCED EXTRUSIONS, LTD. Penetang, Ontario LOK IPO Canada AEROCLO DIVISION 150 Anderson Ave. Moonachie, NJ 07074 AEROFAKO BV PO Box 35 7300 AA Apeldoorn Vlijtseweg 130 Netherlands AEROFILL LTD. Walmgate Road, Perivacle Greenford, Middlesex England AEROPRES CORP. 1108 Petroleum Tower Shreveport, LA 71101 AEROSOL LABORATORY EQUIPMENT CORP. RD#1, Route 10, Box 75 Walton, NY 13856 AEROSOL-SERVICE AG 21 Steinligasse CH-4313 Moehlin Switzerland ALLIED CHEMICAL CORP. Morristown, NJ 07960 ALPHA GAGE & MACHINE TOOL CO. Rt. 86 Downers Grove, IL 60515 ALUSUISSE METALS INC. 21-00 Route 208 Fairlawn, NJ 07410 AMERICAN CAN CO. American Lane Greenwich, CT 06830 AMERICAN GASKET & RUBBER, INC. 9509 Winona Ave. Schiller Park, IL 60176 ANDBRO, INC. Andbro St. Pitman, NJ 08071 ASSOC. OF AMERICAN RAILROADS American Railroads Bldg. Washington, D.C. 20036 ASTM (American Society for Testing and Materials) Washington Bldg. Washington, D.C. 20036 AUTOPRODUCTS INC. 12 S. Denton Ave. New Hyde Park, NY 11040 . AVERY LABEL CO. 1385 Livingston Ave. North Brunswick, NJ 08902 AVON RUBBER CO., Bradford-on-Avon Wiltshire, England AVOSET CO. POBox A Gustine, CA 95322 B LTD. BAMA (British Aerosol Manufacturers Association) 93 Albert Embankment London, SE1 7TU, England BASF WYANDOTTE CORP. 1609 Biddle Ave. Wyandotte, MI 48192 BATTELLE INSTITUTE 505 King Ave. Columbus, OH 43201 BENTLEY MFG. CO., 15123 Colorado Ave. Paramount, CA 90723 INC. BENTON & BOWLES INC. 909 Third Ave. New York, NY 10022 BEN VENUE LABS INC. 270 Northfield Rd. Bedford, OH 44146 BESPAK INDUSTRIES LTD. North Lynn Industrial Estate Kings Lynn, Norfolk PE30 2JJ, England BIO-DYNAMICS, INC. Metier Rd. East Millstone, NJ 08873 BOXAL Div. d'Alusuisse France SA F. 38270 Beaurepaire, France BRIDGEPORT METAL GOODS MFG. 365 Cherry St. Bridgeport, CT 06605 BRISTOL FLOWED GASKET CO. 172 E. Aurora St. Waterbury, CT 06720 BROCKWAY GLASS CO. Brockway, PA 15824 BUSSE BROS. INC. 269 Grove St. Randolph, WI 53956 CO. CAN MAKER'S INSTITUTE 1625 Massachusetts Av., NW Washington, D.C. 20036 CARR-LOWREY GLASS CO. 2201 Kloman St. Baltimore, MD 21203 CASTOLITE CO. Woodstock, IL 60098 CEBAL 98 Blvd. Victor Hugo 92115 Clichy, France CELANESE PLASTICS CO. 26 Main St. Chatham, NJ 07928 CHEMICAL SPECIALTIES MANUFACTURERS ASSOCIATION 1001 Connecticut Ave. NW • Washington, D.C. 20036 CHERRY BURRELL CORP. 2400 Sixth St. SW Cedar Rapids, IA 52400 CITIES SERVICE CO. Tulsa, OK 74110 J.L. CLARK MFG. 2300 Sixth St. Rockford, IL 61101 CO. CLAYTON CORP. 4205 Forest Park Blvd. St. Louis, MO 63108 CLIFF IMPACT DIVISION 33800 Lakeland Blvd. Eastlake, OH 44094 COMITE FRANCAIS DES AEROSOLS 32 Rue de Paradis 75010 Paris, France COMPRESSED GAS ASSOCIATION 500 Fifth Ave. New York, NY 10110 CONSOLIDATED PACKAGING MACHINERY CORP. Division of ATO Inc. 11980 Walden Ave. Alden, NY 14004 CONSUMER PRODUCT SAFETY COMMISSION (CPSC) 5401 Westbard Ave. Washington, D.C. 20207 CONTAINER INDUSTRIES, Londonberry, NH 03053 CONTAINERS, LTD. 266 Frankliln St. Melbourne Victoria 3000 Australia CONTINENTAL CAN CO. 5745 E. River Rd. Chicago, IL 60631 CONTROL PRINT CORP. 67 Sand Park Rd. Cedar Grove, NJ 07009 INC.
Company Listings COSMETIC, TOILETRY AND FRAGRANCE ASSOCIATION 1133 15th St. NW Washington, D.C. 20005 COSTER AEROSOLS LTD. Sterenage Herts England COSTER TECHNOLOGIE SPECIALI SPA Via Fabio Filzi 27 20124 Milan, Italy COZZOLLI MACHINE CO. 403 E. Third St. Plainfield, NJ 07060 CROWN CORK & SEAL CO. 9300 Ashton Rd. Philadelphia, PA 19136 M.E. CUNNINGHAM CO. Rochester Rd. Ingomar, PA 15127 CURRIE MACHINERY CO. 403 E. Third St. Santa Clara, CA 95054 CYPRO INC. 225 N. First Hampstead, MD 21074 D DEMEO BROS. 735 Fifth Ave. New York, NY 10022 DEMERT & DOUGHERTY, INC. 814 Commerce Dr. Oak Brook, IL 60521 DEPT. OF TRANSPORTATION (DOT) 2 Penn Plaza New York, NY 10121 DEUTSCHE AEROSOL VENTIL GMBH 85 Nuremberg 13 Germany DEWEY & ALMY CHEMICAL DIVISION W.R. Grace & Co. 55 Hayden Ave. Lexington, MA 02173 DIGITAL BLENDING SYSTEMS, INC. 2310 Pawtucket Ave. Providence, RI 02901 DIVERSIFIED CHEMICALS & PROPELLENTS CO. Westmont, IL 60559 DRAGOCO GMBH Holzminden/Weser Germany (West) In U.S.A.: Totowa, NJ 07512 £ ELECTRO-TECH SYSTEMS INC. Glenside, PA 19038 EMSON RESEARCH, INC. 118 Burr Court Bridgeport, CT 06605 EPA 401 M St. SW Washington, D.C. 20460 ERTEL ENGINEERING CO. 8-14 Front St. Kingston, NY 12401 ETHYL CORP. Dispenser Products Div. 330 S. 4th St. Richmond, VA 23219 F FACTORY MUTUAL RESEARCH & ENG'G CORP. Norwood, MA 02062 FEA (Federation of European Aerosol Associations) Waisenhausstr. 2 8001 Zurich Switzerland FIELD EMISSION CO. Melrose & Linke Sts. McMinnville, OR 97128 FILLER MACHINE CO. 10 Penn Ave. Rockledge Philadelphia, PA 19111 FIRE PREVENTION DIV. City of New York Municipal Bldg. Room 1014 Brooklyn, NY 11201 FISHER & PORTER CO. 1139 County Lane Rd. Hatboro, PA 19040 FOSTER FORBES GLASS CO. Marion, IN 46953 FOXBORO CORP. 139 Norfolk St. Foxboro, MA 02035 FROST & SULLIVAN, INC. 106 Fulton St. New York, NY 10038 G GENERAL ANILINE & FILM CORP. (GAF) 140 West 51st St. New York, NY 10020 GENERAL ELECTRIC CO. Waterford, NY 12188 GILBERT PLASTICS, INC. 65 Veronica Ave. Somerset, NY 14012 ADOLPH GOTTSCHO, INC. 835 Lehigh Ave. Union, NJ 07083 GRIFFITH LABORATORIES, INC. Microbiotrol Division Central Ave. Alsip, IL 60658 639 H HAARMAN & REIMER GMBH Holzminden, Germany HANDY BUTTON MACHINE CO. 2255 S. Rockwell St. Chicago, IL 60608 HAUMILLER ENGINEERING CO. 960 E. Chicago St. Elgin, IL 60120 HEEKIN CAN CO. 429 New St. Cincinnati, OH 45202 HERBERT PRODUCTS INC. 190 Linden Ave. Westbury, LI, NY 11590 HERCULES INC. 2285 University Ave. St. Paul, MN 55114 HERCULES POWDER CO. Wilmington, DE 19800 HEW (Dept. of Health, Education and Welfare) Food & Drug Administration Independence Ave. Rockville, MD 20852 HUNTLEY BOORNE & STEVENS Headley Rd. East Woodley, Reading England RG5 4SL I IMPACT CONTAINER CORP. Div. Bernzomatic Corp. 740 Driving Park Ave. Rochester, NY 14613 IMPERIAL CHEMICAL INDUSTRIES LTD. Runcorn Cheshire England WA7 4QF IMPERIAL PLASTICS INC. 101 Oakley St. Evansville, IN 47710 INDUSTRIAL HYDROCARBONS INC. 429 S. Cataract Ave. San Dimas, CA 91773 INTERESSEN GEMEINSCHAFT AEROSOL EV IGA Karlstrasse 21 6 Frankfort/Main Republic of West Germany I JBL CORP. PO Box 6426 Spartanburg, SC 29304 JG MACHINE WORKS, INC. 75 Spring St. Paterson, NJ 07501 JOMAR INDUSTRIES Citation Plastics Division Pleasantville, NJ 08232
640 The Aerosol Handbook K KAISER CHEMICALS 300 Lakeside Dr. Oakland, CA 94643 KARTRIDG PAK CO. 807 West Kimberly Rd. Davenport, IA 52808 SA KERVIL, NV Brussels, Belgium KIWI CODERS CORP. 265 E. Messner Dr. Wheeling, IL 60090 KNIGHT ENGINEERING MOLDING CO. 1600 E. Davis St. Arlington Heights, IL 60005 H.C. KROPLINGMBH 649 Schluchtern 1 'Vest Germany L'AIR LIQUIDE, SA Dept. Gai Comprime 75 Quai Dorsay Paris Cedex 07 France 75321 LAWRENCE LIVERMORE NATIONAL LABORATORY Livermore, CA 94550 LECHNER GMBH Postfach 444 77 Singen Hohentweil, Germany LEMAY MACHINE CO. 4725 Green Park Rd. St. Louis, MO 63123 LINDE DIVISION Union Carbide Corp. 270 Park Ave. New York, NY 10017 M MARATHON MORCO CO. 4401 Park Ave. Dickinson, TX 77539 MATEER-BURT CO. 436 Devon Park Dr. Wayne, PA 19087 METAL BOX CO. LTD. Queens House Foxbury Rd. Reading, England R61 3JH METRAMATIC CORP. N. Frontage Rd. Landing, NJ 07850 MCLAUGHLIN GORMLEY KING CO. (MGK) 8810 Tenth Ave. N. Minneapolis, MN 55427 MINE SAFETY APPLIANCES CO. -600 Penn Center Blvd. Pittsburgh, PA 15235 MOBAY CHEMICAL CORP. Hawthorn Rd. Kansas City, MO 64120 MONSANTO CO. 800 N. Lindbergh Blvd. St. Louis, MO 63166 MRM/ELGIN West Third St. New Richmond, WI 54017 N JOHN R. NALBACH ENG. CO. INC. 6139 W. Ogden Ave. Chicago, IL 60650 NATIONAL ACADEMY OF SCIENCES 2101 Constitution Ave. NW Washington, D.C. 20037 NATIONAL CAN CORP. 8101 W. Higgins Rd. -Chicago, IL 60631 NATIONAL FIRE PROTECTION ASSOCIATION Batterymarch Park Quincy, MA 02269 NATIONAL INSTRUMENT CO. 4119FordleighRd. Baltimore, MD 21215 NATIONAL PARKS & CONSERVATION ASSOCIATION 1701 18th NW Washington, D.C. 20009 NATIONAL SAFETY COUNCIL 425 N. Michigan Ave. Chicago, IL 60611 NATIONAL STARCH & CHEMICAL CO. 10 Finderne Ave. Bridgewater, NJ 08807 NATIONAL WILDLIFE FEDERATION 1412 16th NW Washington, D.C. 20036 NEOTECHNIC ENGINEERING LTD. " Upbrooks, Clitheroe Lancashire, England BB7 1NX NEWMAN-GREEN INC. 57 Interstate Rd. Addison, IL 60101 NEW JERSEY MACHINE, INC. 16th St. & Willow Ave. Hoboken, NJ 07036 NEW WAY PACKAGING MACHINERY Box 467 Hanover, PA 17331 PACKAGED FACTS, INC. 274 Madison Ave. New York, NY 10016 PACKAGING MACHINERY MANUFACTURERS INSTITUTE 2000 K St. NW Washington, D.C. 20006 PARAGON PLASTIC, INC. 98 Adams St. Leominster, MA 01453 PEARL CONTAINER CO. ■ San Antonio, TX 98200 PEERLESS TUBE CO. 58 Locust Ave. Bloomfield, NJ 07003 PENICK CORP. 1050 Wall St. W. Lyndhurst, NJ 07071 PENNWALT CORP. 3 Parkway Philadelphia, PA 19102 PERRY INDUSTRIES, INC. Sub-Bermis Inc. New South Rd. & Commerce PI. Hicksville, NY 11802 PHARMAPLASTICS, INC. 1327 Bayard St. Baltimore, MD 21230 PHILLIPS CHEMICAL CO. Petrochemicals Div. Bartlesville, OK 74004 PHILLIPS PETROLEUM CO. Special Products Div. Bartlesville, OK 74004 PLANT INDUSTRIES INC. Selvac Div. Hasbrouck Heights, NJ 07604 PMC INDUSTRIES, INC. 293 Hudson St. Hackensack, NJ 07601 PNEUMATIC SCALE CORP. 68 Newport Ave. Quincy, MA 02171 PRECISION VALVE CORP. 700 Nepperhan Ave. Yonkers, NY 10702 PRESSPACK CORP. 1 Pondfield Rd. Bronxville, NY 10708 R O ODEN CORP. 175 Great Arrow Ave. Buffalo, NY 14207 RACON INC. PO Box 198 ■ Wichita, KS 67201 W.H. REED & CO. 5734 Oakview Lane Punta Gorda, FL 33950
Company Listings 641 REHEIS CHEMICAL CO. Div. Armour Pharmaceutical Co. 235 Snyder Ave. Berkeley Heights, NJ 07922 RING CAN CORP. Oakland-Macon Rd. Oakland, TX 38060 THE RISDON CORP. Electric Ave. Thomaston, CT 06787 SAFETY PACKAGING CORP. 66 DeForest Ave. East Hanover, NJ 07936 SAINT GOBAIN DES JONQUERES 4 Rue Albert de Vatimesnil 9232 Levallois-Perret France SOUTHERN AEROSOL TECHNICAL ASSOCIATION (SATA) PO 43504 Atlanta, GA 30336 SCIENTIFIC & PROCESS INSTRUMENTS Beckman Instruments, Inc. Fullerton, CA 92631 SEAQUIST VALVE CO. 1160 N. Silver Lake Rd. Cary, IL 60013 SEWELL PLASTICS CO. 5111 Phillip Lee Dr. Atlanta, GA 30336 SEXTON CAN CO. 31 Cross St. Everett, MA 02149 SHERWIN WILLIAMS CONTAINERS Container Div. 5325 9th Ave. Countryside, IL 60525 SHIELD CHEMICAL CO. 21 University Rd. Canton, MA 02021 SIERRA CLUB 530 Bush St. San Francisco, CA 94018 SOLFRENE SPA Via Daverio 6 Milan, Italy, 20122 SOUTHERN CAN CO. Tallapoosa, GA 30176 SPRAYON PRODUCTS INC. 26300 Fargo Ave. Bedford Heights, OH 44146 STANDARD KNAPP CORP. Div. Emhart Corp. 125 Main St. Portland, CT 06480 STATE MANUFACTURING CO. .1756 W. Fulton St. Chicago, IL 60612 STATIC CONTROL SYSTEMS GROUP 3M Company Building 518 St. Paul, MN 55101 STEM INDUSTRIES, INC. 303 Fifth Ave. New York, NY 10016 STEPAN CHEMICAL CO. Edens & Winnetka Northfield, IL 60093 STERLING SEAL DIV. Ethyl Corp. 316 W. 16th St. Erie, PA 16500 HERMAN H. STICHT CO. 27 Park PI. New York, NY 10007 SUMMIT PACKAGING SYSTEMS, INC. Grenier Field Manchester, NH 03103 SUNBEAM PLASTICS CORP. 3248 Kansas Rd. Evansville, IN 47711 SUPER WHIP VALVE MFG. 4455 W. Montrose Ave. Chicago, IL 60641 SWIFT & CO. Ill W. Jackson Blvd. Chicago, IL 60604 CO. THE SIMCO CO. TECHNICAL PETROLEUM CO. Lansdale, PA 19440 6233 N Pu]asld Rd SOCIETY OF COSMETIC CHEMISTS (SCC) chlcag°> IL 60646 1995 Broadway, Suite 1701 New York, NY 10023 SOCIETE LABLABO 5 Bis Rue Roger Salengro 92 Montrouge Paris, France SOCIETY OF PLASTICS INDUSTRY INC. 355 Lexington Ave. New York, NY 10017 SOCIETE VALOIS Avenue de L'Europe 78 Marly Le Roi, France TENNECO CHEMICAL CO. 4800 Fournace PI. Bellaire, TX 77401 TERCO, INC. 496 Lunt Ave. Schaumburg, IL 60193 TEXAS INSTRUMENTS CORP. Commerce Park Houston, TX 77006 THOMAS PRODUCTS INC. 20 River Rd. Bogota, NJ 07603 TOWNE-OLLER & ASSOC. 666 Fifth Ave. New York, NY 10103 TUBE MANIFOLD CORP. 429 Bryant N. Tonawanda, NY 14120 TUBENFABRIK R. LECHNER KG 7700 Singen (hohentwiel) Postfach 444 Germany TUBETTIFICIO LIGURE SPA Via Nazionali 99 22040 Abbadia Lariana Lecco, Como Italy u UNDERWRITERS LABORATORIES INC. 333 Pfingsten Rd. Northbrook, IL 60062 UNION CARBIDE CORP. 270 Park Ave. New York, NY 10017 U.S. INDUSTRIAL CHEMICAL CO. Div. National Distillers & Chemical Corp. 99 Park Ave. New York, NY 10016 UPJOHN CO. 7171 S. Portage Rd. Kalamazoo, MI 49001 US BOTTLERS MACHINERY CO. 4019 N. Rockwell St. Chicago, IL 60618 U.S. STEEL CORP. 600 Grant St. Pittsburgh, PA 15230 R.T. VANDERBILT CO. INC. 30 Windfield St. Norwalk, CT 06855 VERNAY LABORATORIES INC. Yellow Springs, OH 45387 VICTOR INDUSTRIES CORP. OF CALIFORNIA 365 E. 20th St. "Chico, CA 95927 THE VIRJUNE MFG. CO. INC. 44 Chapel St. Waterbury, CT 06714 w WHEATON AEROSOL CO. Div. of Wheaton Industries Route 40 Mays Landing, NJ 08330 WHITE METAL MFG. CO. Div. of Dart Industries, Inc. 220 Goffle Rd. Hawthorne, NJ 07506
Index Index terms Links A Abuse Damage due to England, Ireland inhalation ACGIH (Aerosol Conference of Governmental Industrial Hygienists) ACMI (American Can Makers Institute) Actuators brush fitment design for ferrule valve specialty two-piece VariSeal Adolph Gottscho Inc. Advanced Extrusions, Ltd. AerocloDiv. Aerofill Ltd. Aeropres Corp. Aerosect aerosol Aerosol Conference of Governmental Industrial Hygienists (ACGIH) Aerosol sniffing abuse 540 {see also Abuse - inhalation) Aerosol advantages 45 136 Aerosol Research Ltd. 149 Aerosol Service, A.G. 89 106 107 396 Aervalv, SA. 150 Air fresheners 30 36 255 Alcohol in hair spray formulations 324 330 255 258 261 40 150 15 150 175 179 179 177 390 75 156 382 337 62 261 540 255 259 57 531 383 341 258 270 60 385 350 259 274 61 399 351 270 407 274 642 [This page has been reformatted by Knovel to provide easier navigation.
643 Index terms Links Alliance for Responsible CFC Policy Allied Chemical Corp. Alucompack system Aluminum cans availability commercial aspects corrosion crimping designs filling labeling linings production regulations shapes {see also Cans) Aluminum tubes filling for personal products perfumes Alupress-Pack system Alusuisse Metals, Inc. (BoxalDiv) Amerchol Corp. American Can Co. Ames, Dr. Bruce (Ames Test) Analyses finished aerosols 476 flowed-in gasket 477 methods of 464 {see also Testing) AndBro, Inc. 92 319 31 106 75 76 92 89 282 87 380 89 87 86 91 76 37 131 37 112 106 75 92 289 19 48 69 84 101 275 387 90 91 110 76 96 292 59 70 87 109 277 77 109 60 72 88 279 83 110 64 75 99 330 84 284 65 83 100 370 This page has been reformatted by Knovel to provide easier navigation.
644 Index terms Links Antiperspirants filling formulation propellents for toxicology transfer efficiency Apache CanDiv. Apachecan Aquamist Aquasol ARCDiv. of Ethyl Corp. Argentina flammability regulations Atmospheric chemistry Australia flammability regulations Automotive aerosols Autoproducts, Inc. Avoset Corp. AyPak Machinery, Inc. B BAMA (British Aerosol Mfg. Assn.) Barex resin Beard, Walter C. Ben venue Laboratories Blending propellents, costs Blow molding Bomb, Bug Boston rounds glass aerosols Boxal Div. (see also Alusuisse Metals, Inc.) Boyle Midway Div. Bridgeport Brass Co. 20 36 507 374 376 390 23 24 307 253 273 278 335 48 49 60 70 71 70 71 177 177 178 149 169 211 310 209 12 306 379 404 32 149 172 399 207 224 289 290 292 138 100 200 371 307 137 306 202 116 123 76 77 83 84 92 96 109 110 28 33 48 151 [This page has been reformatted by Knovel to provide easier navigation.
645 Index terms Links British Aerosol Manufacturers Association (BAMA) 207 224 289 290 292 Brockway Glass Co. 112 Bromochlorofluorocarbon propellents 334 Budzilek, Edmund 111 118 119 300 304 Bursting of cans 49 53 54 55 97 405 of plastic coated glass aerosols 118 119 120 Busse Bros., Inc. 388 Butane propellents 371 C CAA (Clean Air Act) Can cleaners Can Makers Institute (CMI) Canada CFC regulations DMErn flammability regulations hydrocarbon use methylene chloride use regulations Canadian Cosmetic, Toiletry and Fragrance Assn, (CCTFA) Cans, aluminum bursting of capacity compartmented crimping decomposition design dimensions diameter drop test end unit construction fabrication techniques filling speed 319 389 40 317 355 210 335 369 101 210 75 49 405 61 101 57 327 63 58 289 54 55 62 380 531 57 210 53 82 286 87 60 60 253 54 93 61 61 317 55 63 544 97 This page has been reformatted by Knovel to provide easier navigation.
646 Index terms Links Cans, aluminum (Continued) hot-tanking hydrolytic decomposition in labeling leakage linings lithography nomenclature pressure tolerance production of retail packages quality control of color regulations safety side seam construction silk screening specifications steel composition structural strength temper warranties (See also Aluminum cans) Capacity cans testing Carbon dioxide propellents food aerosols gassing storage Carbona Corp. Carcinogenic chemicals and studies Cardiac Arrhythmia Coster Technologic Caulking aerosol product Cebal Div., Pechiney Ugine Kuhlmann Devel. Inc. Celanese Plastics Co. Celcon containers Celcon resin 53 325 57 56 63 94 58 53 6 95 52 97 69 87 287 49 50 54 68 72 89 57 75 60 55 54 95 55 56 73 90 72 87 61 83 62 59 93 83 98 69 60 61 130 361 34 367 373 93 261 258 150 12 75 138 139 138 82 401 274 276 84 147 This page has been reformatted by Knovel to provide easier navigation.
647 Index terms Links CFC propellents, (see Chlorofluorocarbon propellents) CGMP (Current Good Mfg. Practices) Chapman Reaction Chase Products Co. Checkweighers Chemical Specialties Manufacturers Assn. (CSMA) (see also CSMA) Cherry-Burrell Corp. Chevron Chemical Co. Child resistant caps Chlorofluorocarbon propellents (CFC) exemptions from bans filling gassing glass aerosols hydrolysis Japan production production regulations limiting production shaving cream storage U.S.A. production use in the 80's Chlorofluorom ethane Clark Mfg. Co., J.L. Clayton Corp. Clean Air Act (CAA) Cleaners, valves for Cliff Impact Div., Parker Hannifen Corp. CliXon dispenser Closed Drum Test glass aerosols CMCSA (Canadian Manufacturers of Chemical Specialties Assn.) CM (Can Makers Institute) C02 propellents (see Carbon dioxide propellents) Coders 389 249 311 20 394 61 393 28 195 307 320 381 306 117 325 37 35 317 306 373 35 323 306 75 149 319 181 75 179 200 121 210 40 439 314 186 196 323 396 121 319 397 164 531 76 203 122 57 478 287 256 134 170 85 208 60 508 343 521 172 220 61 This page has been reformatted by Knovel to provide easier navigation.
648 Index terms Links Colgate Palmolive Co. 29 Colognes filling 381 formulation 26 market 112 plastic bottle 139 propellents 328 pump sprays 112 136 {see also Perfumes) Color, in packaging 44 Compounding control charts quality assurance Compressed gases crimp leakage food products solubility toothpaste Confidentiality agreement Conn Chem Div. Conoweld Consolidated Packaging Machinery Corp. Consumer complaints dissatisfaction profile Consumer Product Safety Act Consumer Product Safely Commission (CPSC) Container Industries Inc. Containers, Ltd. Continental Can Co. Continental Filling Corp. Control Print Corp. Cornell Aeronautical Institute 480 462 361 365 362 364 365 551 30 64 104 12 10 11 532 98 110 48 34 57 70 102 48 389 99 364 69 407 11 201 47 60 72 138 72 254 48 62 74 140 74 259 49 66 96 325 96 534 56 69 99 This page has been reformatted by Knovel to provide easier navigation.
Index terms 649 Links Corrosion aluminum cans controlled with neutralizer Cosmetic Toiletries & Fragrances Assn. (CTFA) Cosmetics CGMP for filling methylene chloride in Cost estimating aerosol production of equipment pricing aerosol product Coster Aerosols Ltd. Cover caps actuator aluminum child resistant custom decorating dimensions functions identification chart lift-up cap plastics for rim snap cap slotted snap lock cap Cozzoli Machine Co. CPC International CPSC (Consumer Product Safely Commission) Crimpers Crimping cans collet efficiency glass aerosols magnification of curl 89 18 267 509 478 374 369 44 373 11 383 183 184 193 195 193 198 187 183 187 186 192 185 185 185 374 33 98 395 281 57 297 423 132 284 269 388 196 198 190 192 391 34 201 299 440 478 399 254 259 534 [This page has been reformatted by Knovel to provide easier navigation.
650 Index terms Links Crimping (Continued) plastic coated glass aerosols specifications with CO2 formulas Cress Report on ozone Crown Cork & Seal Co. CSMA (Chemical Specialties Manufacturers Assn.) Aerosol Guide Can Disposal Committee Flame Projection Test Flammability Committee Material Safety Data Sheets CTFA (Cosmetic Toiletries & Fragrances Assn.) Cunningham Co., M.E. Current Good Manufacturing Practices (CGMP) Currie Machinery Co. Customer dissatisfaction Cylinder rounds D d-Con Co. 28 29 93 Decoration caps 198 glass aerosols 111 113 116 124 lithography 94 plastic 142 plastic coated glass aerosols 114 116 118 135 silk screening on cans 87 95 silk screening on glass aerosols 112 116 130 135 Deodorants 515 flammability test results 213 valves for 180 (see also Antiperspirants) 132 286 365 312 47 70 107 61 62 225 252 211 200 262 267 390 249 384 10 123 48 71 281 186 118 230 206 269 439 407 60 72 287 211 304 224 440 478 66 74 343 220 438 227 478 508 This page has been reformatted by Knovel to provide easier navigation.
651 Index terms Links Design cans Dewey & Almy, Div. of W.R. Grace & Co. Dial-A-Spray Digital Blending Systems, Inc. Dimensions cans covercaps Dimethyl ether propellents (DME) flammability of glass aerosols hair sprays paint toxicology of use instead of P152a Dip tube lengths swelling tester Disposal of aerosols devices for plastic aerosols safety of containers Diversified Chemicals & Propellents Co. DME propelents (see Dimethyl ether propellents) Dow Chemical Co. Drackett Industrial Products Div. Drop Testing cans glass aerosols plastic coated glass aerosols Drugs filling du Pont de Nemours, I.E. 19 47 154 268 306 63 56 177 378 58 187 355 359 121 19 30 357 332 167 181 167 454 251 148 249 337 91 29 54 126 129 374 19 319 87 154 60 190 350 74 127 377 47 357 93 293 61 352 154 306 63 268 This page has been reformatted by Knovel to provide easier navigation.
652 Index terms Links E EEC (European Economic Community) Elgin Packaging Machinery Corp. Emson Research Inc. England aerosol deodorant market aerosol market aerosol poisoning aerosol user survey can capacity Gillette packaging home insulation products regulations of cans six-pack packaging Enviro-Spray Systems, Inc. EPA (Environmental Protection Agency) precautionary statements regulation CFC use Equipment cost laboratory plant layout Ertel Engineering Co. Ethers, as propellents Ethylene glycol Ethylene oxide Europe can capacity cans capacity testing cover caps crimp measurements dimensions DMErn filling cans 62 104 75 22 39 255 255 61 41 31 52 43 109 256 523 513 317 373 373 406 420 375 390 306 371 371 61 48 130 198 292 61 355 62 77 92 310 527 318 384 407 421 379 354 294 82 149 320 391 434 175 332 402 176 511 403 This page has been reformatted by Knovel to provide easier navigation.
Index terms Links 653 Europe (Continued) filling lines flammability definition flammability regulations flammability test results gasket use hydrocarbon propellents market plastic coated glass aerosols propellent use regulations regulations on CFC regulations of glass aerosols transportation European Economic Community (EEC) Exxel 376 226 204 208 156 117 38 124 335 117 317 117 542 62 110 157 336 130 204 317 541 Factory Mutual Fair Packaging & Labeling Act (FPLA) FDA (Food, Drug & Cosmetic Act) FEA (Federation of European Aerosol Assn.) Federal Environmental Pest Control Act (FEPCA) Federal Hazardous Substances Act (FHSA) Federal Insecticide, Fungicide & Rodenticide Act (FIFRA) Federation of European Aerosol Assn. (FEA) Feminine hygiene sprays FEPCA (Federal Environmental Pest Control Act) Ferule valves FHSA (Federal Hazardous Substances Act) FIFRA (Federal Insecticide, Fungicide & Rodenticide Act) Filler Machine Co. 239 510 505 59 205 529 201 202 525 59 205 38 529 193 201 202 525 392 248 61 207 221 272 530 61 207 75 194 221 272 530 62 240 279 62 240 279 77 254 511 77 254 511 86 532 522 86 532 522 This page has been reformatted by Knovel to provide easier navigation.
654 Index terms Links Filling aluminum cans aluminum tubes antiperspirants chlorofluorocarbons colognes cosmetics drugs food products frypan release sprays glass aerosols hair sprays insecticides liquid concentrate paints plastic coated glass aerosols powder shaving creams speed of whipped creams Filling lines, European Fire extinguisher aerosols Fischer & Proter Co. Flame Projection Test glass aerosols with DME formulas Flame Propagation Test Flame testing equipment 421 Flamm ability DME 359 electrostatic hazards 227 foam 225 plant layout 378 plastic aerosols 148 sprinkler protection 375 surface 223 380 131 374 306 381 374 374 373 376 131 376 376 391 374 131 390 385 380 373 376 370 378 211 121 359 200 387 376 377 377 132 376 132 385 216 122 208 390 392 380 404 404 This page has been reformatted by Knovel to provide easier navigation.
655 Index terms Links Flammability (Continued) testing Flash Point determination Fleetwood Systems, Inc. FLIP system Flit Flo-Master Fluorocarbon propellents Foam charcoal product flammability test stabilizers sunscreen Fogger, indoor Food aerosols CC^for compressed gases equipment trypan release sprays handling of pancake batter products whipped creams Food Drug & Cosmetic Act (FDA) Formulation antiperspirants cologne confidential statement of formula product reformulation shaving creams skin care products Foxboro Corp. FPLA (Fair Packaging & Labeling Act) 510 France insecticides 27 Freon 306 121 221 464 389 108 63 102 323 225 225 14 225 331 6 365 362 373 376 530 6 307 505 44 23 26 516 246 14 26 307 122 421 32 377 373 131 24 417 378 200 476 36 392 385 398 208 209 254 404 This page has been reformatted by Knovel to provide easier navigation.
656 Index terms Links Frypan release sprays filling {see also Food aerosols) Furniture polish G GAF Gaskets cut gaskets DME effect on flowed in flowed in, analysis leakage methylene chloride effect on neoprene nomenclature of elastomers solvent effect stem swell thickness use in Europe weight loss chart Gassers safety of Gassing chlorofluorocarbons CO2 propellents glass aerosols N2 propellents N20 propellents Sepro cans Gassing room GATT (General Agreement on Tariffs & Trades Section) Gauges A-D dimensions can bead cover cap fitment 19 531 156 356 153 477 157 369 163 162 300 163 160 288 156 430 397 401 306 367 134 403 367 403 237 82 286 453 453 186 20 288 286 301 295 157 401 404 401 289 191 293 404 404 293 This page has been reformatted by Knovel to provide easier navigation.
657 Index terms Links Gauges (Continued) crimp double seam height for baseweight of metal for height weight of valve cup micrometer for G dimension stem height tester testing Gel shaving creams (see also shaving creams) General Agreement on Tariffs & Trades Section (GATT) Gibson girl Gillette Co. Glass Aerosols amber Boston rounds bursting of capacity testing compounding concentrate crimping decoration designs drop testing filling finishes for hot-tanking inspection of labeling of perfumes 111 112 114 123 132 Pharmaceuticals pressure considerations private molds production line regulations safety of 451 453 450 450 450 450 65 14 82 96 23 113 116 118 130 131 132 111 116 126 131 114 134 113 135 111 136 112 116 124 131 118 118 124 452 41 123 119 229 116 122 127 132 112 121 119 128 120 304 124 123 380 114 131 120 126 135 124 123 134 212 This page has been reformatted by Knovel to provide easier navigation.
658 Index terms Links Glass Aerosols (Continued) testing procedures 124 (see also plastic coated glass aerosols) Glass bottles 25 cylinder rounds 123 detects, lib 117 Goodhue, Lyle 47 306 Grace & Co., W.R., (Dewey & Almy Div,) 56 154 293 306 Graham, Earl 47 Grow Group, Inc. 109 H Haase, Franklin Hafel, Dr. Hroar Hair sprays 16 36 323 507 alcohol in DMErn filling flamm ability formulations market profile marketing methylene chloride in product test propellents toxicology user survey valves for Halon Haumiller Engineering U.S.A. Inc. Heekin Can Div. 48 59 69 70 Herbert Products, Inc. Hercules Inc. High speed filling of plastics Hi-Pac Co. Holophane Div., Johns-Manville Inc. 297 47 16 324 19 376 207 18 17 255 369 432 18 261 255 180 334 406 48 391 393 138 93 406 36 213 19 256 370 308 271 256 59 This page has been reformatted by Knovel to provide easier navigation.
Index terms Links Home insulation aerosols Hot-tanking cans glass aerosols plastic coated glass aerosols Huntley, Boorne & Stevens, Ltd. Hydrocarbon propellents alternative to CFC blends Canada, use in glass aerosols price purification of refiners, resellers safe handling specification table storage I IATA (International Air Transport Assn.) IMCO (Intergovernmental Maritime Consultative Organization) Impact Container Corp. Industries Ltd., D.H. Industrial Hydrocarbons Inc. Inhalation of aerosols antiasthmatics consequences methylene chloride tests of propellents toxicology Inhibitors Injection of gases Insect repellents Insecticides filling Flame Projection Test results formula 12 282 53 134 134 48 335 320 349 335 112 338 339 337 236 342 373 31 32 56 72 344 322 115 117 341 397 205 75 380 337 258 270 270 368 330 258 325 367 29 27 376 219 431 209 388 392 540 268 278 327 36 This page has been reformatted by Knovel to provide easier navigation.
660 Index terms Links Insecticides (Continued) methylene chloride in propellents share of market toxicology wasp spray weight loss of product Inspection chemicals finished aerosols labels overcaps shipping containers valve cups valves Insta-Foam Products, Inc. Intergovernmental Maritime Consultative Organization (IMCO) International Air Transport Assn. (LATA) ISO (International Standards Organization) Isobutane Isopentane Italy insecticides 27 J J.G. Machine Works, Inc. 382 391 396 Japan antistatic product 37 capacity testing 130 CFC, glass aerosols 117 CFC, production 37 117 Closed Drum Test 227 colognes 25 deodorant market 23 DME 355 filling 62 flammable aerosol classifications 205 369 28 40 273 365 430 459 475 455 456 456 453 454 31 205 205 82 307 307 476 456 457 209 542 347 348 This page has been reformatted by Knovel to provide easier navigation.
Index terms 661 Links Japan (Continued) flammability regulations hair spray market market of aerosols paint perfumes regulations refillable aerosol Johnson & Johnson Inc. Johnson & Son, S.C. K KartridgPakCo. filling flammability precaution Keene Corp. Kervil.N.V., S.A. Kiwi Coder Corp. Knight Engineering & Molding Co. L Labeling cans claims color selection CPSC labeling program FIFRA requirements filling line speed glass aerosols hot-tanks new product pesticides requirements plastic bottles plastic coated glass aerosols retainer samples 203 16 17 16 17 23 39 30 25 53 84 203 317 177 74 28 29 200 104 105 283 300 307 367 382 383 393 395 396 397 399 307 232 378 109 389 405 196 527 528 57 89 90 510 43 44 534 522 380 381 135 405 9 43 512 142 116 135 484 [This page has been reformatted by Knovel to provide easier navigation.
662 Index terms Links Labeling (Continued) technical data toxicity categories warnings Laboratory equipment layout techniques Laundry aids Layout Lead, bioaccumulation Leakage crimp hot-tanks methylene chloride testing Lechner, S.A., R. Lehn & Fink Products Corp. LeMay Machine Co. Lessenich, Dr. Werner Linings, cans Lithography M Mace 28 Market cologne and perfume 112 European 38 39 tinplate aerosols 48 Marketplace 41 Marketing air freshener survey 255 color in packaging 44 hair spray 17 255 256 packagers check list 42 packaging considerations 42 [This page has been reformatted by Knovel to provide easier navigation. | 517 513 201 420 419 422 30 375 259 72 282 365 405 369 158 84 384 367 205 63 94 209 421 36 379 83 285 75 434 419 100 296 87 160 298 161 301
Index terms 663 Links Marketing (Continued) product introduction strategies Mateer-Burt Co. Measurement can bead can dome crimp depth crimp diameter finished crimp G-dimension gasket thickness valve cup Metabolism, of aerosol chemicals Metal Box Ltd. Metal Goods Manufacturing Co. Metered valve Methyl bromide propellents Methylene chloride propellents Metramatic Corp. Microcompack system Midgley, Thomas ML-STD-1050 sampling table Mine Safety Appliances Co. Mira-Flo Mira-Spra Mounting Cup MRM/Elgin Packaging Machinery Corp. 7 13 390 286 291 289 291 281 301 282 295 298 259 48 90 194 48 175 371 368 394 106 306 447 448 398 101 101 151 393 72 75 149 163 89 193 N N2 propellents, (see Nitrogen propellents) N20 propellents, (see Nitrous oxide, propellents) Nalbach Inc., John R. 382 389 392 398 [This page has been reformatted by Knovel to provide easier navigation.
664 Index terms Links National Can Corp. 48 69 74 75 National Institute of Safety & Health (NIOSH) 262 279 National Instrument Co. 374 392 National Starch & Chemical Corp. 19 NEISS 98 533 Netherlands insecticide aerosols Neumo Div., P & L Industries Ltd. New Jersey Machine Co. New York Bronze Powder Co. New York City Fire Dept. New Way Packaging Machinery Inc. Newman-Green Inc. NIOSH (National Institute of Safety & Health) Nitrogen propellents (N2) gassing Nitrous oxide propellents (N2O) gassing Nomenclature cans valves Norwegian Aerosol Assn. O Occupational Safety & Health Act (OSHA) Odd Nitrogen Process Oden Corp. OPET decoration Open Drum Test Oral Applicator Organosol dome lining variables OSHA (Occupational Safety & Health Act) 27 392 392 30 225 392 149 262 306 403 361 401 58 438 47 172 279 307 404 60 262 311 409 139 141 200 178 65 18 67 262 535 312 208 179 87 87 535 This page has been reformatted by Knovel to provide easier navigation.
Index terms 665 Links Ozone controversy Cress report distribution graphs regulations stratospheric removal P Pacific Packaging Machinery Co. Packaging shrink wrapping six-pack trays Paints filling hydrocarbon propellents for Paint remover toxicology Patent indemnity Pearl Container Co. Peerasol Peerless Tube Co. Perfumes aluminum tubes filling glass aerosols market propellents pump sprays {see also colognes) Perry Industries Inc. PERT diagram Pesticides toxicology Peterson, Harry E. Peterson/Puritan Inc. 112 310 35 308 309 312 311 313 317 312 393 41 43 29 30 36 374 376 404 405 338 261 547 549 83 14 75 84 89 91 75 83 84 24 36 112 132 111 112 114 123 132 136 112 328 112 136 391 3 7 9 523 257 272 47 48 325 401 This page has been reformatted by Knovel to provide easier navigation.
666 Index terms Links Pharmaceuticals First Aid cut spray formula 415 glass aerosols 112 {see also Drugs, Toothpaste) Phillips Chemical Co. 306 337 339 350 352 Plant Industries, Inc. 110 Plastic decoration 142 fabrication 142 for aerosol bottles 142 identification table 148 impact resistance 144 permeation 145 properties 142 safety 145 trays 41 43 Plastic bottles crimping 299 304 for chemical specialties 12 future 148 labeling 142 production of retail packages 6 Plastic coated glass aerosols advantages 114 Boston rounds 123 bursting of 118 crimping 132 cylinder rounds 123 decoration 114 116 135 designs 123 Drop Test 129 hot-tanking 134 labeling 135 limitations 114 manufacture 112 Plastisol 115 134 poly vinyl chloride 112 115 This page has been reformatted by Knovel to provide easier navigation.
Index terms Links 667 Plastic coated glass aerosols (Continued) protective coating PMC Industries, Inc. Pneumatic Scale Corp., Ltd. Poison Prevention Packaging Act (PPPA) Polyethylene solvent action on PPPA (Poison Prevention Packaging Act) Precision Valve Corp. Tower & Trough Test PressPack Corp. PressPack System Pressure-master Prist Preval Spraymaker Product application for new pesticide registration economics safely warranty statistics of development use tests Production aerosol aluminum cans chlorofluorocarbon cost considerations precautions Production line glass aerosols sequence of equipment testing sequence Propane Propellents air-in-liquid graph blends 111 395 393 256 167 256 75 164 395 225 75 105 70 178 110 514 433 545 411 431 35 91 35 44 232 375 131 467 467 307 424 307 112 533 533 110 169 397 105 36 376 114 149 171 401 379 151 153 176 197 531 This page has been reformatted by Knovel to provide easier navigation.
668 Index terms Links Propellents (Continued) bromochlorofluorocarbons butanes carbon dioxide chlorofluorocarbons classification colognes commercial properties table conversion costs definition dimethyl ether ethers fluorocarbons hair sprays halon hydrocarbons insecticides loss of methylene chloride nitrogen nitrous oxide P-152a perfumes pressure vs. temperature selection for aerosols Pump sprays fragrance products Purse-size container 334 371 34 35 373 305 25 321 320 305 355 306 323 18 334 112 236 397 28 282 368 361 361 330 25 328 14 112 177 361 37 381 328 354 308 335 115 329 378 331 328 36 136 373 117 396 117 335 401 121 397 121 344 134 323 134 373 R RCRA (Resource Conservation & Recovery Act) Reed Tester Refillable aerosol 531 118 302 177 This page has been reformatted by Knovel to provide easier navigation.
Index terms Links 669 Regulations Argentina Australia Canada Cans Chlorofluorocarbons CPSC EPA Europe FHSA FIFRA glass aerosols hot-tanks P-ll in antiperspirants state South America toxicology UN Certification marking weights and measures Resins Resource Conservation and Recovery Act (RCRA) Reyner, Dr. Ellis Risdon Manufacturing Co. Roth, Dr. Rotheim, Eric Rousseau, Roy Rowland and Molina 211 209 101 52 317 254 256 117 254 272 118 53 405 307 539 484 253 208 540 19 531 109 92 200 208 47 286 36 210 62 130 279 131 84 269 149 306 92 308 253 69 204 134 203 270 175 306 309 317 70 541 317 272 196 355 313 544 191 279 197 317 321 335 S Safety cans gassers hot-tanking Material Safety Data Sheets 253 97 401 405 262 [This page has been reformatted by Knovel to provide easier navigation.
670 Index terms Links Safety (Continued) plastic 145 Product Safety Warranty 545 safe handling 234 safety guidelines 269 Sampling, statistical 444 Schering-Plough Corp. 387 Schumacler, Th & H 109 Seaquist Valve Co. 149 169 170 172 176 177 179 180 child resistant cap 196 Security aerosols 12 Seam height 164 SEFEL (Society for European Container Standards) 59 61 Selvac dispenser 110 Selvac Div., Plant Industries Inc. 110 Sepro-cans 74 102 107 108 crimping dimensions 304 Foam Flammability Test 225 food aerosols 34 gassing 403 shaving cream 15 Sewell Plastics Co. 140 Sexton Can Co. 74 Seymore of Sycamore, Inc. 30 Shaving creams 12 13 36 chlorofluorocarbons 306 customer complaints 12 filling 385 formulation 14 417 gel 14 hot foam 14 propellents for 306 307 Sepro can 15 women's 14 Sherwin-Williams Co. 48 Shield Chemical Co. 48 This page has been reformatted by Knovel to provide easier navigation.
Index terms Side seam construction cans Sierra Monitor Corp. Silk screening cans glass aerosols Skin care aerosols Society for European Container Standards (SEFEL) Solfrene S.p.A. Solubility compressed gases Solvents toxicology Soudronic, S.A. Soudronic welding Southern Can Co. Spra-tainer Stainless steel aerosols Stolarski and Cicerone Starch chart of metal concentration in Dry Cloth Drag Test valve for Steel composition Stepan Chemical Co. Sterigard Corp. Sticht Co., Herman H. Storage carbon dioxide propellents Chlorofiuorocarbon propellents hydrocarbon propellents (see also Warehouses) Sulfur dioxide Sullivan, William Summit Packaging Systems, Inc. [This page has been reformatted Links 69 398 87 95 112 116 130 135 26 27 36 506 59 61 150 364 278 69 60 63 69 48 60 70 75 14 48 55 60 66 70 71 74 92 313 169 428 432 180 93 19 100 393 373 373 397 373 397 371 47 306 149 154 169 170 180 196 197 Knovel to provide easier navigation.
672 Index terms Links Summit valve in Flame Projection Test 218 Sunbeam Plastics Inc. 549 Super Whip Valve 164 170 172 Surfatest, Inc. 65 Syscon Corp. 409 T Tagliabue Open Cup Test Tanks leakers regulations safety of Taylor Ltd., Div., Samuel Terco, Inc. Tests, testing Ames Test can linings Canadian Flame Tester Closed Drum Test composite flammability Drop Testing Flame Extension Test Flame Projection Test Flame Propagation Test Flammable Field Diameter foam flammability furniture polish glass aerosols hair spray leakage Open Drum Test product use safety guidelines spray starch 221 405 405 405 405 397 105 396 275 66 209 121 220 226 54 209 121 200 121 225 432 124 432 158 200 431 269 432 464 380 397 279 122 331 126 122 208 208 383 399 330 200 211 389 403 370 203 216 This page has been reformatted by Knovel to provide easier navigation.
Index terms 673 Links Tests, testing (Continued) static charge on aerosols Tagliabue Open Cup Test Toxicology valve delivery rate tester Texize Chemical Co. 3MCo. Toothpaste Total Potential Hazard Formula Toxic Substances Control Act (TSCA) Toxicity categories labeling Toxicity studies acute carcinogenic chronic mutagenic retrospective sub-acute teratogenic Toxicology Ames Test antiperspirants carbon dioxide dimethyl ether hair sprays insecticides lead accumulation pesticides regulations solvents testing Tower and Trough Test 229 221 254 272 422 74 391 198 119 257 256 513 254 277 274 275 279 267 464 261 274 365 279 513 274 267 504 268 530 274 275 253 366 357 261 273 269 257 254 278 254 272 279 273 271 272 269 261 274 278 272 267 279 268 This page has been reformatted by Knovel to provide easier navigation.
674 Index terms Links Triboelectric precautions against ignition 231 table 228 TSCA (Toxic Substances Control Act) 257 279 504 530 Tube Manifold Corp. 48 92 Tubettificio Ligure S.p.A 84 U Union Carbide Corp. 138 139 U.S. Bottlers Machinery Co. 392 U.S. Dept. of Agriculture 539 U-t-C gassing 57 91 104 105 109 285 300 V Valois, S.A. 110 149 Valves action diagram 171 body 165 female valve 172 174 ferrule type 174 inserters 394 model CL 166 nomenclature 43 8 one shot 176 177 polyethylene adapter 32 Poly-cell 32 spring 166 stem 164 suggested for products 181 toggle action 170 vertical action 150 vapor 365 VariSeal actuator 177 Victor Industries Corp. 75 Virjune Manufacturing Cp. 75 83 84 92 Viton 369 This page has been reformatted by Knovel to provide easier navigation.
675 Index terms Links W Warehouses 375 fire involving aerosols 242 flammability in 234 international storage 248 storage of aerosols 239 285 {see also Storage) Wasp spray 365 {see also Insecticides) Weight loss Wheaton Aerosol Co. 26 111 112 115 118 SAF Process Whipped creams filling propellents for {see also Food aerosols) White Metal Manufacturing Co., Div. of Wheeling Stamping Co. White's propellent WHO (World Health Organization) toxicology 267 World chlorofluorocarbon production 318 consumption 35 production by country 38 39 storage of aerosols 248 X X-r chart 469 Z Zytel 146 431 26 121 123 373 307 75 307 111 138 385 328 112 145 404 329 115 202 This page has been reformatted by Knovel to provide easier navigation.