2-Hydroxy-5-[[4-[(1-hydroxy-5-sodiosulfo-2-naphthalenyl)azo]-1-naphthalenyl]azo]benzoic acid sodium salt

5-Amino-2-hydroxybenzoic acid diazotization, and Naphthalen-1-amine coupling, product to diazotization, and 5-Hydroxynaphthalene-1-sulfonic acid coupling.

black. Soluble in water for purple black, right amount soluble in ethanol for sauce red, slightly soluble in Acetone, insoluble in other organic solvent. In concentrated sulfuric acid for brilliant green, dilution after pale red light brown; In concentrated nitric acid for wine, and then into orange. Dye aqueous solution to join concentrated hydrochloric acid for pale red light brown; Join concentrated sodium hydroxide solution for purple black.

Standard	Ironing Fastness	Light Fastness	Fulling		Persperation Fastness	Soaping	Water
			Alkali	Acid
ISO	5	5	4	4	4-5	5	5