6771-80-8

3,3′-Dimethoxylbenzidine double nitriding, first and 4-Amino-5-hydroxynaphthalene-1,3-disulfonic acid, and then in three alkaline conditions and 4-Hydroxy-7-(phenylamino)naphthalene-2-sulfonic acid coupling.

green light blue. Soluble in water for blue purple, and adequate soluble in alcohol. The strong sulfuric acid for Tracy in blue, and in purple for diluted. The dye solution to join strong hydrochloric acid for red light blue; Add thick sodium hydroxide solution for dark purple, have precipitation.

Standard	Acid Resistance	Alkali Resistance	Light Fastness	Soaping		Water
				Fading	Stain	Fading	Stain
ISO	3-4	3-4	6	3-4	2	4	2