The Printing

Ink Manual

The Printing

Ink Manual FOURTH EDITION

Edited by

Dr R. H. Leach, Dr C. Armstrong, J. F. Brown, M. J. Mackenzie, 1. Randall and Dr H. G. Smith

BLUEPRINT An Imprint of Chapman & Hall in association with

Published by Blueprint, an imprint of Chapman & Hall, 2-6 Boundary Row, London SEt BHN.

Chapman & Hall, 2-6 Boundary Row, London SEI 8HN, UK

Van Nostrand Reinhold Inc., 115 5th Avenue, New York NY10003, USA

Chapman & Hall Japan, Thomson Publishing Japan, Hirakawacho Nemoto Building, 7F, 1-7-11 Hirakawa-cho, Chiyoda-ku, Tokyo 102, Japan

Chapman & Hall Australia, Thomas Nelson Australia, 102 Dodds Street, South Melbourne, Victoria 3205, Australia

Chapman & Hall India, R. Seshadri, 32 Second Main Road, CIT East, Madras 600 035, India

First edition 1961 Reprinted 1963 (with revisions) Second edition 1969 Third edition 1979 Reprinted 1984 Fourth edition 1988 Reprinted 1988, 1989, 1991

© 1961,1969,1979,1988 - Society of British Printing Ink Manufacturers Ltd Softcover reprint of the hardcover 1st edition 1988

Typeset in Meridien by Best-set Typesetter Ltd, Hong Kong

ISBN-13: 978-1-4684-6908-0 e-ISBN-13: 978-1-4684-6906-6 DOl: 10.1007/978-1-4684-6906-6

Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the UK Copyright Designs and Patents Act, 1988, this publication may not be reproduced, stored, or transmitted, in any form or by any means, without the prior permission in writing of the publishers, or in the case of reprographic reproduction only in accordance with the terms of the licences issued by the Copyright Licensing Agency in the UK, or in accordance with the terms of licences issued by the appropriate Reproduction Rights Organization outside the UK. Enquiries concerning reproduction outside the terms stated here should be sent to the publishers at the London address printed on this page.

The publisher makes no representation, express or implied, with regard to the accuracy of the information contained in this book and cannot accept any legal responsibility or liability for any errors or omissions that maybe made.

A catalogue record for this book is available from the British Library

Contents

Preface xi The Editors and Authors XIII

I The Nature of Printing Inks

2

c. Armstrong, Coates Brothers Inks Ltd

1.1 Visual characteristics of inks 1.2 The nat ure of printing inks as determined by the

printing process 3 1.3 The drying characteristic<; 5 1.4 The adhesive nature of printing inks 6 1.5 The resistance properties of printing inks 7

The Printing Processes B. Blunden and J. Birkenshaw, PIRA

2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10

The letterpress process The offset lithographic process The gravure process The f1exographic process The screen printing proce.ss Non-impact printing processes Other printing processes Print recognition Substrate selection The need for communication

10

II 20 35 44 50 54 59 60 65 67

3 Colour and Colour Matching 69 J. Brown, Mander-Kidd (UK) Ltd

3.1 The physical nature of colour 69 3.2 The perception of colour 72 3.3 Additive and subtractive colour mixing 78 3.4 Origins of colour in printed material 84 3.5 Graphic reproduction 86 3.6 The measurement of colour 88 3.7 The recording of colour data and the specification

of colour 94

vi CONTENTS

3.8 Colour matching 98 3.9 Instrumental colour match prediction 102

References 107

4 Raw Materials 109 M. Clayton, Ault & Wiborg General Printing Inks

Section I Pigments 110 4.1 Yellow pigments III 4.2 Orange pigments 117 4.3 Red pigments 120 4.4 Green pigments 139 4.5 Blue pigments 142 4.6 Violet pigments 149 4.7 Brown pigments 152 4.8 Black pigments 154 4.9 White pigments and extenders 156 4.10 Pearle scent materials 161 4.11 Metallic pigments 161 4.12 Fluorescent pigments 162 4.13 General properties of pigments 163

Section II Dyestuffs 172 4.14 Acid dyes 172 4.15 Basic dyes 174 4.16 Solvent dyes 178 4.17 Disperse dyes 180

Section III Oils 183 4.18 Drying vegetable oils 183 4.19 Other oils 188

Section IV Resins 192 4.20 Natural resins 193 4.21 Synthetic resins 199

Section V Solvents 225 4.22 Hydrocarbon solvents 228 4.23 Alcohols 231 4.24 Glycols 232 4.25 Ketones 234 4.26 Esters 235

Section VI Plasticisers 244

Section VII Waxes 249 4.27 Synthetic waxes 250 4.28 Petroleum waxes 253 4.29 Natural waxes 255

Section VIII Driers 258 4.30 Liquid driers 258 4.31 Paste driers 260

CONTENTS vii

5

6

7

Section IX Miscellaneous additives 260 4.32 Chelating agents 260 4.33 Antioxidants 261 4.34 Surfactants 262 4.35 Deodorants and reodorants 264 4.36 Pure chemicals 265 4.37 Defoaming agents 269 4.38 Laking agents 270

Section X Raw materials for radiation curing systems 27 J

4.39 Pigment selection 271 4.40 Prepolymers 272 4.41 Reactive dil L1ents 27 4 4.42 Photoinitiators 274 4.43 Additives and inhibitors 275

Section XI Health and safety at work References

Letterpress Inks c. B. Burdall, Usher- Walker pic

280 28J

282

5.1 Nature of the process 282 5.2 General characteristics of letterpress inks 284 5.3 Physical properties 286 5.4 Raw materials 289 5.5 Letterpress ink formulation 294 5.6 Ink-related problems and their possible solutions 302 5.7 New developments304

Lithographic Inks 308 P. Ford and R . .J. Tuft, Coates Brothers Inks Ud

6.1 General characteristics of litho inks 312 6.2 Drying mechanisms) I') 6.3 Physical properties 321 6.4 Formulating principles 328 6.5 Typical inks and varnishes 343 6.6 Ink-related problems and their possible solutions 352 6.7 Recent and fu ture trends 361

Gravure Inks 368 E. Cawkill and B. Ellison, BASF Coatings + Inks Ltd

7.1 General characteristics 36<) 7.2 Physical properties of inks and their measurement 376 7.3 Form ulating principles 382 7.4 Inks and varnishes for specific end-L1sc

applications 393 7.5 Printing ink faults 426 7.6 Future developments 429

viii CONTENTS

8 Flexographic Inks 435 F. C. Wyatt, Lorilleux & Bolton Ltd

8.1 General characteristics of the inks 437 8.2 Physical properties of flexographic inks and

their measurement 442 8.3 Formulating principles 447 8.4 Inks and varnishes for special purposes 456 8.5 Ink-related printing problems and possible solutions 476 8.6 Recent and future trends 478

9 Screen Inks 481 J. Joannou, Coates Brothers Inks Ltd

9.1 Important characteristics of screen inks 481 9.2 Requirements of raw materials 487 9.3 Inks for paper and board 490 9.4 Inks for impervious surfaces 493 9.5 Inks for plastic containers 499 9.6 Textile inks 502 9.7 Transfer inks 504 9.8 Overprint varnishes 505 9.9 Daylight fluorescent inks 506 9.10 Process inks 507 9.11 Metallics 509 9.12 Ink-related printing problems 510 9.13 Recent and future trends 513

10 Radiation Curable Systems 51 s, R. Holman, BASF Coatings + Inks Ltd

10.1 Electromagnetic radiation and electron beams 517 10.2 Microwave and radio frequency drying 521 10.3 Infra-red curing systems 522 10.4 Ultraviolet and electron beam curable inks and

varnishes 525 10.5 Radiation curing equipment 552 10.6 State of the art and future trends 560 Further reading 561

11 Inks for Special Purposes 562 R. Marsh, Coates Brothers Inks Ltd

ILl Non-impact printing 562 11.2 Speciality screen inks 571 11.3 Inks for the electronics industry 573 11.4 Inks for laminated plastics 578 11.5 Inks for wallcoverings 578 11.6 Textile transfer inks 580 11.7 Sterilisation inks 582

CONTENTS

12

13

14

11.8 Metal decorating II. 9 Letterset printing

Manufacture of Inks and Varnishes M. 1. Heath, Lorilleux & Bolton Ltd, and A. J. Wild. Usher- Walker pIc

ix

585 588

592

12.1 General requirements 592 12.2 The manufacturing processes '>93 12.3 Mixing equipment 616 12.4 Milling equipment 624 12.5 Handling, storage and manufacture of UV inks 644 12.6 Manufacture of newspaper inks 645 12.7 Handling and storage of inks 648 12.8 Modern production trends 655 12.9 The future 660

Rheology of Printing Inks 666 A. Tabbernor, Mander-Kidd (UK) Ltd

13. I Flow in ideal systems 667 13.2 Deviations from Newtonian behaviour 668 13.3 Apparatus for the measurement of the viscosity

of Newtonian liquids 675 13.4 Practical measurements for non-Newtonian

systems 678 13.5 Tack 685 13.6 Tack measurement 686 13.7 Ink distribution and related matters 689 13.8 Rheological measurements and machine design 694 References 696

Testing, Control and Analysis E. Cawkill, BASF Coatings + Inks Ltd and D. Easterly, Coates Brothers Inks Ltd

14.1 14.2 14.3 14.4 14.5 14.6 14.7 14.8 14.9 14.10 14.11 14.12 14.13 14.14

Standard tests Sampling technique Pigment testing Chips and pre-dispersions Dye testing Resins Varnishes and oils Solvents Radiation curing products Miscellaneous materials Ink quality control Short-term ink testing Long-term ink testing Press performance tests

699

700 700 701 710 710 711 714 720 724 726 726 727 731 735

x

15

14.15 Dry print performance tests 14.16 Analysis of printing inks References Further reading

Health, Safety and the Environment G. 1. May and 1. Orpwood, Coates Brothers Inks Ltd

15.1 Handling of dangerous substances in the manufacture of printing inks

15.2 Mechanical and operational aspects 15.3 Specific printing ink applications 15.4 Some international constraints

Glossary of abbreviations

References

Index

CONTENTS

740 751 779 779

780

785 809 820 826

831

832

839

Preface

The Printing Ink Manual was first published in 1961 under the auspices of the Society of British Printing Ink Manufacturers with the object of providing an authoritative work on printing ink technology. This, the fourth edition, continues that purpose and presents a comprehensive study of the current 'state of the art' in the ink industry. For those starting in the printing ink industry it is a textbook dealing with all aspects of the formulation and manufacture of printing ink. For the ink technician it is a practical manual and useful source of reference. For printers and users of printed material the manual supplies helpful information on the nature and behaviour of ink both on the printing press and as the finished print. Readers with a little scientific knowledge will have no difficulty in using the manual, but as in previous editions, sufficient chemistry and physics have been introduced to assist the advanced technician and research scientist.

In the eight years since the last edition very substantial changes have taken place in ink technology, and accordingly the book has been entirely rewritten by a new panel of authors all of whom arc currently engaged in the printing ink or associated industries. While retaining the general structure of previous editions, the chapters have been arranged in a more logical order. Those dealing with ink formulation reflect the considerable changes that have taken place in the printing industry; letterpress inb have largely been superseded by lithographic inks for both packaging printing and newspaper production, and gravure and ilexographic inks are now applied to a much greater variety of substrates for packaging. Developments in manufacturing methods have also been substantial. Both milling and mixing techniques have benefited by new designs in machinery and the introduction of electronic and computerised controls.

Two important chapters have been added to this edition of the manual, one dealing with Radiation Curable Systems, the other with Health, Safety and Environment. Radiation curable systems have now become widely used for drying printing inks and are based on quite different ink technology. This technology is explained in depth together with details ot the special raw materials required. Matters of health and safety at work and environmental pollution have assumed great importance since the last edition of the manual. Therefore a chapter has been included which

xii PREFACE

offers a survey of the current legislation both in the United Kingdom and other countries concerning the requirements for the safe manufacture, handling and transport of printing inks and also considers the limitations in the use of raw materials.

It is hoped that with its new edition, this highly respected reference book will continue to serve as a guide for all involved in the printing ink industry worldwide.

ACKNOWLEDGEMENTS

R. H. Leach Editor-in-Chief

The editors wish to thank Barry Hermiston of Coates Brothers Inks Ltd, who compiled the index. They also wish to thank those who supplied diagrams and illustrations not acknowledged elsewhere and those mem­bers of the Society of British Printing Ink Manufacturers who have kindly checked the ink formulations and chemical structural formulae at the proofing stage.

The Editors and Authors

Editors Dr R. H. Leach, Editor-in-Chicf Dr C. Armstrong, Technical Director, Coates Brothers Inks Ltd. Mr J. F. Brown, Scientific Services Manager, Mander-Kidd (UK) Ltd. Mr M. J. Mackenzie, Deputy Technical Director, Usher-Walker pic. Mr L. Randall, Deputy Managing Director, Usher-Walker pic. Dr H. G. Smith, Technical Director, Fishburn Division, BASF Coatings +

Inks Ltd

Authors Chapter I Dr C. Armstrong Coates Brothers Inks Ltd.

2 Mr B. W. Blunden PIRA Mr J. W. Birkenshaw PIRA

3 Mr J. F. Brown Mander-Kidd (UK) Ltd. 4 Mr M. J. Clayton Sun General Printing Ink 5 Mr G. B. Burdall Usher-Walker pic 6 Mr P. I. Ford US Printing Ink Corporation

Mr R. J. Tuft Coates Brothers Inks Ltd. 7 Dr E. Cawkill BASF Coatings + Inks Ltd.

Mr B. A. Ellison BASF Coatings + Inks Ltd. 8 Mr F. C. Wyatt Lorilleux & Bolton Ltd. 9 Mr G. Joannou Coates Brothers Inks Ltd.

10 Dr R. J. Holman BASF Coatings + Inks Ltd. I I Mr R. Marsh Coates BroThers Inks Ltd. 12 Mr M. J. Heath Lorilleux & Bolton Ltd.

Mr A. J. Wild Usher-Walker pic. 13 Mr A. Tabbernor Mander-Kidd (UK) Ltd. 14 Dr E. Cawkill BASF Coatings + Inks Ltd.

Mr D. Easterby BASF Coatings + Inks Ltd. 15 Mr G. J. May Coates Brothers Inks Ltd.

Mr J. P. Orpwood Coates Brothers Inks Ltd. Index Mr B. N. Hermiston Coates Brothers Inks Ltd.