5-[[2-[(2-Amino-8-hydroxy-6-sulfo-1-naphthalenyl)azo]-4-sulfophenyl]sulfonyl]-2-hydroxybenzoic acid trisodium salt

Preparation

2-Hydroxy-5-(2-amino-4-sulfophenylsulfonyl)benzoic acid?diazotization, under acid condition and 6-Amino-4-hydroxynaphthalene-2-sulfonic acid coupling.

Properties and Applications

brilliant blue light red. Soluble in water for red, slightly soluble in ethanol for magenta. In concentrated sulfuric acid for orange brown, dilution after pink. Dye aqueous solution to join concentrated hydrochloric acid to red; Join concentrated sodium hydroxide solution for purple.

Standard	Ironing Fastness	Light Fastness	Fulling		Persperation Fastness	Soaping	Water
			Alkali	Acid
ISO	4	6	5	4	4-5	5	5