6-Amino-4-hydroxy-3-[[4'-[(2,4-diaminophenyl)azo]-1,1'-biphenyl-4-yl]azo]naphthalene-2-sulfonic acid sodium salt

4-(4-Aminophenyl)benzenamine double nitriding, first and Benzene-1,3-diamine coupling, and then in alkaline conditions and 6-Amino-4-hydroxynaphthalene-2-sulfonic acid? coupling.

dark red light brown to dark red. Soluble in water for red, and adequate soluble in alcohol. The strong sulfuric acid for hidden cyan, diluted red for sauce. The dye solution to join strong hydrochloric acid for red sauce, precipitation; Add thick sodium hydroxide solution for orange brown, have precipitation.

Standard	Acid Resistance	Alkali Resistance	Light Fastness	Soaping		Water
				Fading	Stain	Fading	Stain
ISO	3-4	3	3	3		2-3