4,5-Dihydroxy-3-[[4'-[(1-hydroxy-4-sulfo-2-naphtyl)azo]-3,3'-dimethyl-1,1'-biphenyl-4-yl]azo]-2,7-naphthalenedisulfonic acid trisodium salt

3,3′-Dimethylbenzidine double nitriding, first and 4,5-Dihydroxynaphthalene-2,7-disulfonic acid coupling, again with 4-Hydroxynaphthalene-1-sulfonic acid coupled

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

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