Preparation
2,4-Dimethyl-5-aminobenzenesulfonic acid diazo, coupled with the 4-Hydroxynaphthalene-1-sulfonic acid, and then into aluminum salt deposit color.
Properties and Applications
yellow light red. Soluble in water for yellow light red, slightly soluble in alcohol. The strong sulfuric acid is a deep in the red, red after diluted precipitation; In nitric acid solution for orange, then become yellow. The dye solution to join strong hydrochloric acid red slightly deepen; Add thick sodium hydroxide solution for orange.
