sodium hydroxy[2-hydroxy-3-[(2-hydroxy-1-naphthyl)azo]-5-nitrobenzenesulphonato(3-)]chromate(1-)

3-Amino-2-hydroxy-5-nitrobenzenesulfonic acid diazo, and Naphthalen-2-ol coupling, and then in aqueous solution together with formic acid chromium heating, in 130 ° C keep 0.5 ~ 1.5 hours to form chromium complex.

red. Purplish red powder, soluble in water for purplish red color. The strong sulfuric acid dyes for purple, the diluted solution turned pale red purple, after gradually precipitation. Levelness and white sex are good. Copper ions in dyeing color change to blue; Iron ion in light blue and light. Used for wool, polyamide fiber, silk and their blended fabric dyeing and printing, also used in leather shading and organic pigments.

Standard	Light Fastness	Soaping		Persperation Fastness	Oxygen bleaching		Fastness to seawater
		Fading	Stain		Fading	Stain	Fading	Stain
ISO	5-6	4		5	1		3-4
AATCC	4-5	2		5			5