Oil-soluble black oil-soluble black is oil-soluble nigrosine
Nigrosine, commonly known as aniline black or Jingyuan. A black dye that is directly produced on cotton fabrics and is insoluble in common solvents. Widely used in dyeing and printing of cotton fabrics. When dyeing, the cotton fabric is first immersed in a solution prepared with aniline salt, etc., and then oxidized to dye black. The dyes are resistant to sun and rain, and are very fast to hot soap solutions and dilute bleach solutions. It is blue-black when oxidized too much, and it is easy to cause brittle damage. It can turn green when under-oxidized or reduced.
Physical and chemical properties: Appearance is black uniform powder. Insoluble in water, soluble in ethanol, benzene and toluene, soluble in oleic acid and stearic acid. It is blue-black in ethanol solution, blue to blue-black in concentrated sulfuric acid, blue-black precipitate after dilution, and blue to blue-black in concentrated nitric acid. Acid and alkali resistance and light resistance are good. Index name Index Appearance Black uniform powder shade and similar tinting strength of standard product, divided into 100±5 of standard product Moisture content, % ≤3 Ash content, % ≤2 Fineness (residue content through mesh sieve), % ≤0.5 Uses : Mainly used for coloring of advanced insulating bakelite, carbon paper, leather shoe polish, rubber, etc.