4,6-Dibenzothiophenedisulfonic acid, 3,7-bis[[2-(phenylamino)-1-naphthalenyl]azo]-, 5,5-dioxide, disodium salt

3,7-diaminobiphenyl sulfone-4,6-disulfonic acid double nitriding, and N-phenyl-2-naphthylamine (2 Moore) coupled.

red light navy blue. Soluble in water for blue, soluble in ethanol for violet blue. The strong sulfuric acid to purplish red color, diluted into yellowish gray. In aqueous solution is to add strong hydrochloric acid have dark precipitation, add sodium hydroxide to blue.

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