sodium 3-[(2,4-diaminophenyl)azo]-4-hydroxybenzenesulphonate

3-Amino-4-hydroxybenzenesulfonic acid diazotization, and Benzene-1,3-diamine coupling.

dark red light brown. Soluble in water for red light yellow, slightly soluble in ethanol, Acetone and Cellosolve. In concentrated sulfuric acid for brown light orange, dilution after orange; In concentrated nitric acid for red, then become yellow brown. Dye aqueous solution to join concentrated hydrochloric acid for orange; With strong caustic of golden orange.

Standard	Ironing Fastness	Light Fastness	Fulling		Persperation Fastness	Soaping	Water
			Alkali	Acid
ISO	4-5	5	3-4	2	5	4-5	5
AATCC	5	6-7	3-4		4	4	5