aniline diazo, and Naphthalen-1-amine coupling, again diazo, in alkaline conditions and 6-Amino-4-hydroxynaphthalene-2-sulfonic acid? coupling.
Properties and Applications
red light grey. Moderate soluble in water for violet and grey or black, slightly soluble in alcohol. ?In concentrated sulfuric acid for the gray light blue (plus purple), diluted red for sauce. Dye with strong hydrochloric acid solution for red sauce; Add thick sodium hydroxide solution for green light black, with precipitation.
![6-Amino-4-hydroxy-3-[[4-(phenylazo)-1-naphtyl]azo]-2-naphthalenesulfonic acid sodium salt Structure](/CAS/GIF/6227-04-9.gif)