Pigments distinction from dyes

Use of the compound to synthesize soluble dyes ceased as of 1986, when better dyes from other sources were introduced. The distinction between dyes and pigments is not always clear. Pigments are almost without exception insoluble and exist as finely divided solid powders that are insoluble but wettable under the eonditions of use. Dyes are almost always soluble organic substances used in coloring textiles or other fibrous substances. 

Colour is introduced into these materials and applications using substances known as dyes and pigments, or collectively as colorants. The essential difference between these two colorant types is that dyes are soluble coloured compounds which are applied mainly to textile materials from solution in water, whereas pigments are insoluble compounds incorporated by a dispersion process into products such as paints, printing inks and plastics. The reader is directed to Chapter 2 of this book for a more detailed discussion of the distinction between dyes and pigments as colouring materials. 

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