disodium 7-hydroxy-8-[[4-[(4-sulphonatophenyl)azo]phenyl]azo]naphthalene-2-sulphonate

4-((4-Aminophenyl)diazenyl)benzenesulfonic acid diazo, and 7-Hydroxynaphthalene-1-sulfonic acid coupling.

colourful yellow red. Soluble in water and ethanol to the red orange. The strong sulfuric acid in blue, diluted into pink. In water solution to join strong hydrochloric acid is palm orange; Add thick sodium hydroxide solution for dark purple.

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