C.I. Direct brown 26

Preparation

4-(4-Aminophenyl)benzenamine double nitriding, first coupled with 2-Hydroxybenzoic acid, and then and 5-Aminonaphthalene-2-sulfonic acid and 8-Aminonaphthalene-2-sulfonic acid coupling, its product to diazo, and 5-Aminonaphthalene-1-sulfonic acid coupling.

Properties and Applications

dark red light brown. Soluble in water for olive brown, and adequate soluble in alcohol is palm yellow light. The strong sulfuric acid for dark purple, diluted dark green to shallow blue to olive brown precipitation. The dye solution to join strong hydrochloric acid have brown light olive precipitation; Add thick sodium hydroxide solution have orange brown precipitation.