Industrial Photoinitiators: A Technical Guide / Edition 1

Paperback (Print)
Buy New
Buy New from BN.com
$86.58
Used and New from Other Sellers
Used and New from Other Sellers
from $86.54
Usually ships in 1-2 business days
(Save 17%)
Other sellers (Paperback)
  • All (5) from $86.54   
  • New (3) from $86.54   
  • Used (2) from $128.91   

Overview

The use of photoinitiators in the UV curing process shows remarkable possibilities in myriad applications. Highlighting critical factors such as reactivity, cure speeds, and application details, Industrial Photoinitiators: A Technical Guide is a practical, accessible, industrially oriented text that explains the theory, describes the products, and outlines the practice in simple language for the novice and expert alike.

The basics of UV light

The book begins by examining the nature of UV light and the types of commercial UV lamps that are available. It discusses the light absorption process and the excited states that are produced by the photoinitiator prior to the production of radicals. Next, the book examines the structure of the photoinitiator and the mechanism by which a reactive species is formed, along with the deactivating processes that inhibit the various photophysical and photochemical steps that occur as radicals are produced.

Commercial photoinitiators

Providing a list of companies and suppliers, the author explores the distinct groups of commercial photoinitiators and the variations in their structure. He describes the factors that determine which photoinitiators should be chosen for a particular application and how the different types are used. He also explains the reasons why a cured coating may display yellowing and describes the use of stabilizers to reduce the yellowing effect.

Cationic curing

Exploring a small but growing area of interest in the UV curing industry, the book concludes by discussing cationic curing and examines the different scope of parameters and different chemistry involved. It also describes factors that affect the use of cationic photoinitiators.

Based on more than 30 years of experience working with photoinitiators, W. Arthur Green offers a unique resource that provides product developers and others working in industry with the practical information they need to fully understand the basics of this evolving field.

Read More Show Less

Product Details

  • ISBN-13: 9781439827451
  • Publisher: CRC Press
  • Publication date: 4/23/2010
  • Edition number: 1
  • Pages: 302
  • Product dimensions: 0.60 (w) x 0.90 (h) x 1.80 (d)

Meet the Author

W. Arthur Green received his degree in industrial chemistry in 1964 and has more than 40 years of experience working with photoinitiators. Since his retirement, he has continued to work part-time in the UV curing industry as a technical advisor and still presents papers and takes part in training sessions for companies involved in photoinitiators.

Read More Show Less

Table of Contents

Acknowledgments xiii

Introduction xv

Chapter 1 Let there be light 1

1.1 The electromagnetic spectrum 1

1.2 The generation of UV energy 2

1.2.1 The medium-pressure mercury lamp 3

1.2.1.1 The standard mercury arc lamp 3

1.2.1.2 The electrodeless microwave-powered UV lamp 5

1.2.1.3 Wavelength output of the medium-pressure mercury lamp 7

1.2.2 Doped lamps 8

1.2.3 The low-pressure mercury lamp 10

1.2.4 The high-pressure mercury lamp or capillary lamp 10

1.2.5 Flash lamps 10

1.2.6 Fluorescent lamps 11

1.2.7 Excimer lamps 11

1.2.8 Light emitting diodes 11

1.2.9 Lasers 12

1.3 The light absorption process 13

1.4 UV safety and ozone 15

References 15

Chapter 2 A little chemistry 17

2.1 Free radical chemistry 17

2.2 The chromophore and absorption of UV energy 18

2.2.1 The generation of radicals 18

2.2.2 The polymerization process 20

2.3 Type I photoinitiators: Mechanism of the scission process 22

2.3.1 Alpha-scission 22

2.3.2 Beta-scission 23

2.4 Type II photoinitiators: Mechanism of the abstraction process 24

2.4.1 Hydrogen abstraction from a donor molecule 24

2.4.2 Intramolecular γ-hydrogen abstraction: The Norrish Type II reaction 25

2.5 The influence of molecular substitution on absorption and photoactivity 26

2.5.1 Type I photoinitiators: Substitution effects 27

2.5.2 Type II photoinitiators: Substitution effects 28

2.5.3 Commercial photoinitiators 30

2.6 Photobleaching 31

2.7 Diverse mechanisms: Variations on the Type I and Type II process 33

2.7.1 Acyloximino esters 33

2.7.2 Anthraquinones 34

2.7.3 BCIM and the lophyl radical 35

2.7.4 Benzoylformate esters 36

2.7.5 Substituted maleimides as photoinitiators 37

2.7.6 Phosphine oxides and secondary scission 38

2.7.7 Photo-acid generation 39

2.7.8 Photo-base generation 41

2.7.9 Anthracene peroxy radicals 42

2.8 The thiol-ene photopolymerization 43

References 45

Chapter 3 Academics unlimited 47

3.1 Triplet lifetimes and monomer quenching reactions 48

3.2 Modification of hydroxyacetophenones 49

3.3 Alkylaminoacetophenones and wavelength selection 50

3.4 Phosphine oxides: Reactivity and solvolytic stability 53

3.5 Benzophenone and thioxanthone triplet reactions 54

3.6 Substituted benzophenones 58

3.7 Substituted thioxanthones 60

3.8 Novel photoinitiators 64

3.9 Radical reactions 66

3.9.1 Primary radical reactions 67

3.9.2 Recombination reactions 67

3.9.3 Rearrangement reactions 68

3.9.4 Disproportionation reactions 69

3.9.5 Oxygen effects and chain transfer 70

3.9.6 Termination reactions 71

3.9.7 Identification of radicals and excited states 71

References 72

Chapter 4 Commercial photoinitiators 75

4.1 Type I photoinitiators (see Tables A.1 and A.2) 75

4.1.1 Hydroxyacetophenones 75

4.1.2 Alkylaminoacetophenones 77

4.1.3 Benzil ketals and dialkoxyacetophenones 78

4.1.4 Benzoin ethers 79

4.1.5 Phosphine oxides 80

4.1.6 Specialties 82

4.1.6.1 Acyloximino esters 82

4.1.6.2 BCIM and HABIs 82

4.1.6.3 Photoacid generators 83

4.1.6.4 Alphahaloacetophenones 84

4.1.6.5 Trichloromethyl-S-triazines 84

4.1.6.6 Photobase generators 85

4.2 Type II photoinitiators 86

4.2.1 Benzophenones 86

4.2.2 Substituted benzophenones 87

4.2.3 Thioxanthones 88

4.2.4 Anthraquinones 89

4.2.5 Benzoylformate esters 90

4.2.6 Camphorquinone 91

4.3 Blends of photoinitiators 91

4.4 Migration and polymeric photoinitiators 93

4.4.1 Migration of low-molecular weight species 93

4.4.2 Polymeric photoinitiators 95

4.4.2.1 Polymeric Type I photoinitiators 98

4.4.2.2 Polymeric Type II photoinitiators 98

4.4.2.3 Polymeric aminobenzoate hydrogen donors 99

4.4.3 The "Nestlé list" 99

4.5 Visible light curing 99

4.5.1 Titanocenes 101

4.5.2 Dibenzylidene ketones 101

4.5.3 1,2-Diketones 101

4.5.4 Ketocoumarins 102

4.5.5 Dye sensitized photoinitiation 102

4.5.5.1 Dye plus coinitiator 102

4.5.5.2 Dye plus borate salt 103

4.5.5.3 Dye plus HABIs 103

4.5.5.4 Dye plus S-triazine 103

4.6 Water-based UV curing 103

4.7 Hydrogen donors 105

4.7.1 Tertiary amines 106

4.7.2 Alpha-amino acids 108

4.7.3 Other types of hydrogen donor 108

References and further reading 109

Chapter 5 Factors affecting the use of photoinitiators 115

5.1 Matching the photoinitiator absorption to the UV source 115

5.1.1 Absorption properties 115

5.1.2 Formulating for LED UV 116

5.1.2.1 Type I photoinitiator LED systems 117

5.1.2.2 Type II photoinitiator LED systems 117

5.1.2.3 The use of ITX as a sensitizer for LEDs 118

5.2 Oxygen inhibition 118

5.2.1 Radical-oxygen interaction 118

5.2.2 Nitrogen and carbon dioxide inertion 119

5.2.3 The effect of viscosity on cure 121

5.3 Film thickness, surface and depth cure, shrinkage and adhesion 123

5.3.1 Surface and depth cure 123

5.3.2 Shrinkage and adhesion 127

5.4 Sensitization and synergy 128

5.4.1 Sensitization 128

5.4.2 Synergy 130

5.5 The effect of pigments on the UV curing process 131

5.5.1 Pigment absorption and the pigment window: Choice of photoinitiator 131

5.5.2 Replacing ITX 133

5.5.3 Titanium dioxide whites and carbon blacks 134

References and further reading 136

Chapter 6 Photoproducts and the yellowing of coatings 139

6.1 Intrinsic color, photoyellowing, and oxidation products 139

6.2 The formation of photoproducts 139

6.2.1 Photoproducts from Type I photoinitiators 140

6.2.2 Photoproducts from Type II photoinitiators 145

References 147

Chapter 7 Cationic chemistry 149

7.1 The light absorption process and the generation of acid 150

7.1.1 Triphenylsulphonium salts 150

7.1.2 Diphenyliodonium salts 151

7.2 Epoxy polymerization and the dark reaction 153

7.2.1 The polymerization process 153

7.2.2 The effect of alcohols and chain transfer 154

7.2.3 Hybrid cure 155

7.3 Triarylsulphonium salts (see Tables A.7 and A.8) 155

7.3.1 Sulphonium salts that may release benzene 156

7.3.2 Sulphonium salts that are "benzene free" 157

7.4 Dialkylphenacylsulphonium salts 160

7.5 Diaryliodonium salts 160

7.5.1 Iodonium salts that may produce benzene 162

7.5.2 Iodonium salts that are "benzene free" 162

7.6 Ferrocenium salts 164

References and further reading 165

Chapter 8 Factors affecting the use of cationic photoinitiators 167

8.1 The influence of the anion 167

8.2 Photochemical radical decomposition of onium salts 168

8.3 Sensitization of the cationic photoinitiator 169

8.3.1 Extension of absorption wavelength by a sensitizer 169

8.3.2 Sensitizers for cationic photoinitiators 170

8.4 The influence of temperature on the polymerization 170

8.5 The effect of water on polymerization 172

References and further reading 172

Appendix A Tables and absorbance graphs 175

Appendix B Further information 279

Index 283

Read More Show Less

Customer Reviews

Be the first to write a review
( 0 )
Rating Distribution

5 Star

(0)

4 Star

(0)

3 Star

(0)

2 Star

(0)

1 Star

(0)

Your Rating:

Your Name: Create a Pen Name or

Barnes & Noble.com Review Rules

Our reader reviews allow you to share your comments on titles you liked, or didn't, with others. By submitting an online review, you are representing to Barnes & Noble.com that all information contained in your review is original and accurate in all respects, and that the submission of such content by you and the posting of such content by Barnes & Noble.com does not and will not violate the rights of any third party. Please follow the rules below to help ensure that your review can be posted.

Reviews by Our Customers Under the Age of 13

We highly value and respect everyone's opinion concerning the titles we offer. However, we cannot allow persons under the age of 13 to have accounts at BN.com or to post customer reviews. Please see our Terms of Use for more details.

What to exclude from your review:

Please do not write about reviews, commentary, or information posted on the product page. If you see any errors in the information on the product page, please send us an email.

Reviews should not contain any of the following:

  • - HTML tags, profanity, obscenities, vulgarities, or comments that defame anyone
  • - Time-sensitive information such as tour dates, signings, lectures, etc.
  • - Single-word reviews. Other people will read your review to discover why you liked or didn't like the title. Be descriptive.
  • - Comments focusing on the author or that may ruin the ending for others
  • - Phone numbers, addresses, URLs
  • - Pricing and availability information or alternative ordering information
  • - Advertisements or commercial solicitation

Reminder:

  • - By submitting a review, you grant to Barnes & Noble.com and its sublicensees the royalty-free, perpetual, irrevocable right and license to use the review in accordance with the Barnes & Noble.com Terms of Use.
  • - Barnes & Noble.com reserves the right not to post any review -- particularly those that do not follow the terms and conditions of these Rules. Barnes & Noble.com also reserves the right to remove any review at any time without notice.
  • - See Terms of Use for other conditions and disclaimers.
Search for Products You'd Like to Recommend

Recommend other products that relate to your review. Just search for them below and share!

Create a Pen Name

Your Pen Name is your unique identity on BN.com. It will appear on the reviews you write and other website activities. Your Pen Name cannot be edited, changed or deleted once submitted.

 
Your Pen Name can be any combination of alphanumeric characters (plus - and _), and must be at least two characters long.

Continue Anonymously

    If you find inappropriate content, please report it to Barnes & Noble
    Why is this product inappropriate?
    Comments (optional)