6,8-Bis(phenylamino)naphthalene-1-sulfonic acid and 2,5-Diamino-4-methoxybenzenesulfonic acid?condensation, then product to (add) ammonia Cuprous oxide as catalyst for air oxidation.
Properties and Applications
blue light purple. Soluble in water and ethanol for red purple. In concentrated sulfuric acid for green, red purple after diluted. Dye aqueous solution to join sodium hydroxide amaranth, accompanied by precipitation. Used for acetate fiber of protoplasm coloring.