C.I. Direct Brown 46

Preparation

4-(4-Aminophenyl)benzenamine double nitriding, first coupled with 2-Hydroxybenzoic acid, again with 5-Aminonaphthalene-2-sulfonic acid and 8-Aminonaphthalene-2-sulfonic acid coupling, its product to diazo, in alkaline conditions and 6-Amino-4-hydroxynaphthalene-2-sulfonic acid?coupling.

Properties and Applications

dark brown olive green light. Soluble in water for palm light olive, soluble in ethanol. The strong sulfuric acid in the navy for, for the shallow olive gray after diluted. The dye solution to join strong hydrochloric acid have Gray light purple precipitation; Add thick sodium hydroxide solution have orange brown precipitation.