2-Amino-4-nitrophenol diazotization, and 4-Hydroxynaphthalene-1-sulfonic acid coupling.
Properties and Applications
dark red light brown. Soluble in water for purple, slightly soluble in ethanol for red light purple. In concentrated sulfuric acid for magenta, dilution after red orange. Dye aqueous solution to join concentrated hydrochloric acid for orange; Join concentrated sodium hydroxide solution for brown light orange.
