Benzoic acid, 5-[[4'-[(2-amino-3-hydroxy-6-sulfo-1-naphthalenyl)azo][1,1'-biphenyl]-4-yl]azo]-2-hydroxy-, disodium salt

Preparation

4-(4-Aminophenyl)benzenamine double nitriding, first coupled with 2-Hydroxybenzoic acid, and then in acetic acid medium and 6-Amino-7-hydroxynaphthalene-2-sulfonic acid?coupling.

Properties and Applications

yellow light brown. Moderate soluble in water for yellow brown, slightly soluble in ethanol is palm light yellow to olive. The strong sulfuric acid for blue-ray in black, yellow light brown for diluted. The dye solution to join strong hydrochloric acid for olive brown, have precipitation; Add thick sodium hydroxide solution for orange brown.

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