2,7-Naphthalenedisulfonic acid, 4,4'-[(3,3'-dimethyl[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[3-amino-, tetrasodium salt

Preparation

3,3′-Dimethylbenzidine double nitriding, and 3-Aminonaphthalene-2,7-disulfonic acid (2 Moore) coupled.

Properties and Applications

colourful red blue light. Soluble in water for palm light orange to red, slightly soluble in alcohol. The strong sulfuric acid for blue, orange to red light after dilute for brown. Dye with strong hydrochloric acid solution for orange brown, have precipitation; Add thick sodium hydroxide solution for palm to red light orange, precipitation.

Standard	Acid Resistance	Alkali Resistance	Light Fastness	Soaping		Water
				Fading	Stain	Fading	Stain
ISO	2-3	4	2	1		1