The red insect dyes: carminic, kermesic and laccaic acids and their derivatives.

Three groups of insect dyes are described: three cochineal dyes, the kermes dye and the lac dye. The major color components are carminic acid, kermesic acid and laccaic acids, respectively. These dyes are red anthraquinone derivatives. The chemical structures are described. All of these dyes have extensive histories that are related briefly; however, only American cochineal is of commercial importance today. Two manufactured derivatives of cochineal, carmine and acid-stable carmine (4-aminocarminic acid) are described in some detail including the chemical identity, toxicity, stability, and staining and non-staining applications.