5-Amino-3-[[4'-[[6-amino-1-hydroxy-5-[(4-nitro-2-sulfophenyl)azo]-3-sulfo-2-naphtyl]azo]-1,1'-biphenyl-4-yl]azo]-4-hydroxy-2,7-naphthalenedisulfonic acid tetrasodium salt

2-Amino-5-nitrobenzenesulfonic acid diazo, in acid conditions and 7-Amino-4-hydroxynaphthalene-2-sulfonic acid coupling, 4-(4-Aminophenyl)benzenamine?double nitriding, in alkaline conditions and 4-Amino-5-hydroxynaphthalene-2,7-disulfonic acid?coupling, and then in alkaline conditions and formation of accidentally coupled nitrogen compounds.

dark red light blue to navy blue. Soluble in water for the navy, slightly soluble in alcohol. The strong sulfuric acid for blue, for purple diluted. The dye solution to join strong hydrochloric acid for deep purple; Add thick sodium hydroxide solution for deep purple.

Standard	Acid Resistance	Alkali Resistance	Light Fastness	Soaping		Water
				Fading	Stain	Fading	Stain
ISO	3-4	5	2	1-2		2