Composition and classification of organic pigments

1. Composition

Organic pigments and dyes are derived from unsaturated naphthalene, anthracene, nitrogen naphthalene, aminoanthracene and other carbocyclic or heterocyclic aromatic organic compounds.

2. Chromophore

Unsaturated atomic groups can selectively absorb certain parts of the spectrum to show color, so these unsaturated atomic groups are called chromophores.

3. Classification

Toner: an insoluble pigment formed by precipitation of water-soluble acidic or basic dyes with metal salts or acids.

Lake: It is a colored pigment made by precipitating soluble dyes on insoluble carriers, such as aluminum hydroxide and aluminum barium white.

Pigment dyes (Pigmentdyestuff)