tetrasodium 7-amino-4-hydroxy-3-[[6(or 7)-sulphonato-4-[[6(or 7)-sulphonato-4-[(3-sulphonatophenyl)azo]naphthyl]azo]naphthyl]azo]naphthalene-2-sulphonate

Preparation

3-Aminobenzenesulfonic acid diazo, and 5-Aminonaphthalene-2-sulfonic acid and 8-Aminonaphthalene-2-sulfonic acid first coupling, its product to diazo, and 5-Aminonaphthalene-2-sulfonic acid and 8-Aminonaphthalene-2-sulfonic acid?second coupling, again diazo, in alkaline conditions and 7-Amino-4-hydroxynaphthalene-2-sulfonic acid third coupling.

Properties and Applications

dark blue. Black powder. Soluble in water for red light blue. The strong sulfuric acid for Gray light blue, blue for red after diluted. The dye solution with 10% after sulfuric acid into dark purple; Add 30% sodium hydroxide solution into the red. Water-soluble general, more sensitive to hard. Exhaust the dye sex good, excellent discharge. Copper ions in dyeing, iron ion a slight change color. Used for cotton, viscose and silk dyeing and printing, also can be used for cotton/rayon blended fabric dyeing and printing, also used for paper color.