Template:Redirect Template:Chembox Chrysoine resorcinol is a synthetic azo dye which was formerly used as a food additive.Template:Citation needed In Europe, it was banned as a food additive in 1977.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> In the US, it was banned in 1988.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
Chrysoine resorcinol can be used as a pH indicator with a color change between pH 11 and pH 12.7. In colorimetry, it has an absorption maximum of 387 nm.
PreparationEdit
Acid orange 6 can be synthesised via the azo coupling of sulfanilic acid and resorcinol,