Acid Orange Ⅱ Chinese alias: Acid Orange Ⅱ; Acid Brilliant Orange GR Properties: Acid Orange Ⅱ (CAS: 523-44-4) is golden brown powder. Water-soluble red light yellow, adding hydrochloric acid to produce brown precipitate; adding sodium hydroxide solution was dark brown. Soluble in ethanol orange; in concentrated sulfuric acid was magenta, produce diluted brown precipitate; golden yellow in concentrated nitric acid. Insoluble in concentrated sodium hydroxide solution. In case of copper ions to red when dyed dark; in case of iron light and dark color. Uses: Acid Orange Ⅱ (CAS: 523-44-4) is mainly used for direct printing wool, silk, nylon and fabric dyeing, bright color, good levelness, but poor fastness. Also used in leather, paper and bio-products, coloring, pure product can be used as food coloring, also be used as an indicator. Description: Acid Orange Ⅱ (CAS: 523-44-4) is based on the amino acid and 2-naphthol for raw materials, will amino acid diazotization, coupling with 2-naphthol to give the product. Salting out, filtration, drying, crushing derived products.