tetrasodium 3,3'-(carbonyldiimino)bis[6-[[1-hydroxy-6-(phenylamino)-3-sulphonato-2-naphthyl]azo]benzoate]

2-Amino-5-nitrobenzoic acid diazo, in alkaline conditions and 4-Hydroxy-7-(phenylamino)naphthalene-2-sulfonic acid coupling, and then will the nitro reduction, and will get the amino nitrogen compounds for light accidentally gasification.

dark purple. Soluble in water for red light purple, slightly soluble in alcohol. The strong sulfuric acid for blu-ray in red, for purple diluted. The dye solution to join strong hydrochloric acid for purple, have precipitation; Add thick sodium hydroxide solution for red light purple, have precipitation.

Standard	Acid Resistance	Alkali Resistance	Light Fastness	Soaping		Water
				Fading	Stain	Fading	Stain
ISO	3	5	6	4		5