What are organic pigments, the concept of organic pigments

Non-ferrous substances can be divided into two categories, namely inorganic non-ferrous substances and organic non-ferrous substances. A class of colored organic compounds can make fiber materials or other substances dye bright and firm colors through appropriate methods, which are called organic dyes; They can be used in water or solvents, or converted into soluble solutions, or treated into a dispersed state to stain fibrous substances. Another type of colored organic compound is insoluble in water and insoluble in the medium used, and the substance that colors the colorant in a highly dispersed particle state is called organic pigment. The corresponding inorganic colored substances, such as some metal oxides, sulfide salts, complexes (CdS cadmium yellow, Cr, 0 chromium green, Pb, 04 red dan, HgS vermilion, K. [FeCN)] Prussian blue, etc.), insoluble in water or use medium, and can color the substance, it is called inorganic pigment. Organic pigments have a different concept from organic dyes, which are usually soluble (soluble in water or organic solvents) and can be adsorbed or chemically bound to dyed fibers or mechanically fixed. However, some are insoluble (such as vat dyes, disperse dyes), which can be applied as dyes by changing the dyeing process, so individual insoluble dyes such as alcohol-soluble dyes or solvent dyes (Solvent Dyes), vat dyes can be used as organic pigments through the pigmentation process to make them have the performance of pigments. At the same time, some water-soluble dyes, such as containing -SO3Na, -COONa and basic dyes, can interact with specific lake agents such as alkaline earth metal salts (CaCl, BaCl, etc.), organic acids or inorganic heterogeneous acids (tannins, phosphotungsten molybdate, etc.) to precipitate the dye on the inorganic carrier (aluminum hydroxide, clay, etc.) and transform it into insoluble colored substances, constituting a class of important significanceof lake pigments. To sum up, although pigments and dyes are different concepts, they are indeed a class of closely related colored compounds. And as

Organic pigments must be colored compounds with special application properties, such as color vibrancy, hue or light, tinting strength or tinting strength, lightfastness and weathering, heat and solvent resistance, and dispersion properties. Therefore, although many vat dyes have excellent lightfastness, weather fastness and heat stability, when applied in the powder state, their tinting strength is low and the brightness is poor, and most varieties are not suitable for pigment application, and only a few individual varieties such as Vat blue RSN Vat yellow G can be used as organic pigments for paint coloring.