7-Hydroxy-8-[[2-methyl-4-[[6,8-bis(sodiosulfo)-2-naphthalenyl]azo]phenyl]azo]naphthalene-1,3-disulfonic acid disodium salt

Preparation

7-Aminonaphthalene-1,3-disulfonic acid diazotization and coupling O-Methylaniline, methanesulfonic acid hydrolyzable group, and diazotization, and with 7-Hydroxynaphthalene-1,3-disulfonic acid coupling.

Properties and Applications

colourful red blue light. Soluble in water for product red, not soluble in alcohol. In the strong sulfuric acid as dark blue, diluted into product red. In water solution to join strong hydrochloric acid by product red to wine red; Add thick sodium hydroxide solution for dark brown.

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