4 Additives for Ink Manufacture Zuzanna _ Z ol ek-Tryznowska Department of Printing Technology, Faculty of Production Engineering, Mechanics and Printing Institute, Warsaw University of Technology, Warsaw, Poland OUTLINE 4.1 Definition of an Additive 57 4.2 Surfactants: Wetting and Dispersing Agents 58 4.2.1 Antifoaming Agents 59 4.3 Adhesion Promoters 59 4.4 Waxes 60 4.5 Driers 61 4.6 Rheology Modifier 61 4.7 Other Additives 61 4.7.1 Antioxidants and Antiskinning Agents 62 4.7.2 Alkalis 62 4.7.3 Biocides and Fungicides 62 4.7.4 Chelating Agents 62 4.7.5 Deodorants 62 4.8 Additives for Radiation-Curing Inks 62 4.9 Performance Additives 63 4.9.1 Ionic Liquids 63 4.9.2 Hyperbranched Polymers 63 References 65 4.1 Definition of an Additive The definition of additives is, “any substances that are added in small quantities to a coating material to improve or to modify certain properties of the finished coating or of the coating material during its manufacture, storage, transport, or application” (Bieleman, 2008). In general, additives are used in an ink formulation <5% (by weight) in order to alter selected properties of coating (Tracton, 2006b). Typically, the contents of an additive are about 1.5% of the quantity of the ink formula. Printing ink is generally composed of a pigment and an extender, resin or binder, and solvent. The addition of an additive to the printing ink affects various ink properties. Moreover, a properly selected additive helps to achieve the required properties of the liquid ink and dried ink layer by a significant modification of the properties of the individual ingredients of the ink. However, it is important to understand the relationship and interactions between the ingredients of the ink. Today, according to a report by MarketsandMarkets. com, the global value of the ink additives market was estimated to be $629.02 million and it is expected to increase. The most important seems to be the technical impact of the additive on the final ink property, while the significance of the additive is expressed by its contribution to the improvement of the specific prop- erty of the ink (Bieleman, 2008). However, additives are much more expensive than other components of the printing ink, but their use is justified by the influ- ence of a small amount of additive on the final quality of the dried ink film. In order to minimize the evaporation of organic solvents into the environment, the attention of the printing industry is focused on printing with water- based printing inks, because water-based inks are cheaper, water costs almost nothing, and more importantly, water does not pollute the environment (Havlinova, Cicak, Brezova, & Hornakova, 1999). However, printing with water-based printing inks on plastic film has certain problems. The adhesion of water-based ink to the plastic film and wet rubbing of Printing on Polymers. http://dx.doi.org/10.1016/B978-0-323-37468-2.00004-X Copyright © 2016 Elsevier Inc. All rights reserved. 57