Definition Pigments-Dyes

Pigments, dyes, and extenders are defined in DIN 55943 under the heading colorants (coloring materials). Further standards are DIN 55944 and 55949. Similar definitions are given in ASTM D16-84, IS0 4617, and IS0 4618. A pigment is defined as a substance that is insoluble in the application medium (e.g., a paint) and is used as a colorant or on account of its corrosion-inhibiting or magnetic properties. A dye is defined as a colorant that is soluble in the application medium. 

While the properties of (soluble) dyes are determined almost exclusively by their chemical constitution, application characteristics of pigments—which are by definition insoluble in the medium in which they are applied (see Sec. 1.1) — are largely controlled by their crystalline constitution, i.e., by their physical characteristics. This is discussed in the next chapter. 

Blue materials used as pigments or dyes, were the lapis lazuli (ultramarine), azurite (armenium). Both of these sometimes were called caeruleum. Indicum was indigo imported from India. Purpurissium was the name given to a pigment made from chalk colored with a purple dye, but whether from murex, indigo or woad does not seem definitely stated. 

A number of definitions need to be clarified before the reader can completely understand the chapters that follow. These definitions fall into a number of categories and clarify color and colorant properties. The difference between a pigment and a dye has already been made clear. 

A definition for plastics dyes that has evolved in practical use is somewhat more useful than traditional ones namely, a dyestuff is a dyestuff when used in a given polymer because it is soluble in the polymer. In contrast, pigments are therefore defined as not being soluble in the polymer being colored. 

The DIN definition of the term colorant includes both dyes and pigments. In contrast to dyes, pigments are practically insoluble in the binder. They consi.st of solid particles generally with a uniform chemical composition and are mainly transition metal oxides, oxide hydrates, sulfides, silicates, sulfates or carbonates (.see Table 5.9-1). 

Definition PEG ether of cetearyl alcohol Formula R(OCH2CH2)nOH, R = blend of cetyl and stearyl radicals, avg. n = 16 Properties Nonionic Toxicology TSCA listed Uses Wetting agent, emulsifier, detergent, solubilizer, dispersant in hydrophobic conditions dye and pigment carriers textiles mfg. of wax emulsions and polishes for household and industrial use antistat emulsifier in cosmetics emulsifier and solubilizer for pharmaceuticals Ceteareth-17 CAS 68439-49-6 (generic)... 

Synonyms POE (25) castor oil Definition PEG deriv. of castor oil with avg. 25 moles of EO Properties Nonionic Toxicology TSCA listed Uses Lubricant, emulsifier in lubricants for plastics, metals, textiles clay/pigment dispersant, rewetting agent, softener, dyeing assistant for paints, paper, textiles, and leather surfactant, emulsifier in cosmetics, pharmaceuticals solubilizer for essential oils, vitamins, and pharmaceuticals in food-pkg. adhesives... 

Definition Diester of isostearic acid and polyglycerin-3 Empirical C45H88O9 Properties Nonionic Toxicology TSCA listed Uses Emulsifier, emollient, thickener, solvent in cosmetics, creams, lotions, lip prods., pharmaceuticals dye and pigment wetting agent food emulsifier pharmaceutical excipient... 

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