31 октября, 2015 
Pokraskin Chapter 2 described the vital function of polymers as film formers in paints and coatings. However, successful paint formulation needs to meet other properties such as color and opacity that the binder alone cannot provide. Pigments are one of the most important components of coatings.
Colorants are materials used to impart color, which may be either pigments or dyestuffs. Therefore, before entering into the discussion about pigments, they must be distinguished from dyestuffs. The essential difference between them is their solubility in the medium in which they are incorporated.
Pigments and dyes are defined in DIN 55943, ISO 4617 and ISO 4618. A dye is defined as a colorant that is soluble in the application medium. A pigment is defined as a substance that is insoluble in the application medium and is used as a colorant or on account of its corrosion inhibiting or magnetic properties. Because of their solubility, dyestuffs, when used in coatings, produce transparent films, which limits their use in particular types of coatings that require a high degree of opacity.
More generic to the paint industry, pigments can also be defined as organic or inorganic fine-particulate solids, substantially insoluble in paint vehicles, that are used to impart certain properties to paint such as color, opacity, corrosion inhibition, mechanical properties and durability.
Some pigments called lakes are dyes that are combined with fine, inert inorganic particles as a base or carrier, which in turn give insoluble colorant particles. On the other hand, organic pigments that do not contain an inorganic carrying base are known as toners. In
V. Mannari, C. J. Patel: Understanding Raw Materials © Copyright 2015 by Vincentz Network, Hanover, Germany ISBN: 978-3-86630-603-5
Europe, the term toners is applied to insoluble metal salts of water — soluble acid or basic dyestuffs.
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