3,3'-[(1,1'-Biphenyl-4,4'-diyl)bis(azo)]bis[4-hydroxy-1-naphthalenesulfonic acid sodium] salt

4-(4-Aminophenyl)benzenamine double nitriding, and 4-Hydroxynaphthalene-1-sulfonic acid (2 Moore) coupled.

red light purple. Soluble in water for purplish red color, not soluble in alcohol. The strong sulfuric acid in the dark for, for the red light purple diluted. The dye solution to join strong sodium hydroxide solution for blue-ray red.

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