Roll-to-roll Vacuum Deposition of Barrier Coatings

by Bishop, Charles A.

• ISBN13: 9781118946145
• ISBN10: 1118946146
• Edition: 2nd
• Format: Hardcover
• Copyright: 2015-10-05
• Publisher: Wiley-Scrivener

Summary

It is intended that the book will be a practical guide to provide any reader with the basic information to help them understand what is necessary in order to produce a good barrier coated web or to improve the quality of any existing barrier product.

After providing an introduction, where the terminology is outlined and some of the science is given (keeping the mathematics to a minimum), including barrier testing methods, the vacuum deposition process will be described. In theory a thin layer of metal or glass-like material should be enough to convert any polymer film into a perfect barrier material.  The reality is that all barrier coatings have their performance limited by the defects in the coating. This book looks at the whole process from the source materials through to the post deposition handling of the coated material. This holistic view of the vacuum coating process provides a description of the common sources of defects and includes the possible methods of limiting the defects. This enables readers to decide where their development efforts and money can best be used to improve the barrier performance of their own process or materials.

The 2^nd edition contains at least 20% new material including additional barrier testing techniques that have been developed and testing and cleaning equipment brought to market since the 1^st edition was published in 2010. The topic of adhesion is covered in more detail and there is a section on the Hanson Solubility Parameter which is a method of predicting the solubility of gases or liquids in materials.

Author Biography

Charles Bishop left school at 16 to start an engineering apprenticeship completing it as a Toolmaker. Opting to return to education he took a degree in Materials Technology. Here the seeds of vacuum processing were sown in the form of a final year project working on bone implants. Moving to the Physics Department he went on to complete Masters and Doctorate degrees on different aspects of vacuum deposition. After a brief time as a post doctoral researcher he moved into industry for the next 15 years before setting up his own consultancy business in 1998.
He is the author of the book Vacuum deposition onto webs, films and foils, 3rd edition and author or co-author of over 90 papers and 5 patents. He contributes a regular column in Converting Quarterly as well as technical articles. He was presented with a SVC Mentor Award in 2008. Currently he is the Editor of the Vacuum Web Coating blog that is accessed through www.convertingquarterly.com on behalf of AIMCAL as well as a regular lecturer at the AIMCAL Converting Schools and presenter of a number of Webinars also offered by AIMCAL.

Table of Contents

Biography

Acknowledgements

Preface

1 Introduction 1

1.1 Packaging 5

1.1.1 Opaque Barrier 6

1.1.2 Transparent Barrier 8

1.2 Markets 10

References 16

2 Terminology 19

2.1 Hansen Solubility Parameter 29

2.2 Permeability Models 33

2.3 Barrier Improvement Factor 39

2.4 Tortuous Path Model 40

2.5 Terminology Summary 44

References 45

3 Measurements 51

3.1 Permeation Measurements 52

3.2 Durability Testing 60

3.3 Adhesion 65

3.4 Pinholes 67

3.5 Surface Energy 69

3.6 Coefficient of Friction 74

3.7 Coating Thickness 76

3.8 Coating Conductivity or Resistivity 79

3.9 Transmittance, Reflectance and Ellipseometry 80

3.10  Standard Test Methods   81

3.10.1 Permeability Tests 81

3.10.2 Other Mechanical or Optical Performance Tests 82

References 83

4 Materials 89

References 100

5 Packaging Materials Calculations 103

5.1   Demonstration  Calculations 108

References 112

6 Substrates, Surfaces, Quality and Defects 115

6.1 Substrates    115

6.1.1 Oligomers   120

6.1.2 Additives   121

6.1.3 Contamination     126

6.1.4 Surface Quality   132

6.2 Substrate Cleaning  134

6.3 Substrate Plasma Treatments     139

6.4 Wetting and Adhesion      149

6.5 Subbing or Planarisation Layers and Over-Coatings 157

References  161

7 Vacuum Deposition Processing      171

7.1 Nucleation, Growth and Modification   171

7.2 Managing the Substrate Heat Load      185

7.3 Web Winding in Vacuum     205

7.4 Troubleshooting     222

References  224

8 Vacuum Deposition     231

8.1 Resistance Heated Evaporation   232

8.2 Plasma Enhanced Chemical Vapour Deposition (PECVD)      249

8.3 Electron Beam Evaporation Sources     251

8.4 Induction Heated Evaporation Source   254

8.5 Magnetron Sputter Deposition Sources  255

8.6 Atomic Layer Deposition (ALD)   265

8.7 Other Deposition Processes      271

References  272

9 Summary   285

9.1 Cleanliness 285

9.2 Substrates 286

9.3 Coatings 287

9.4 Over Coatings 288

9.5 Multilayers 288

9.6 Conclusion 288