Polycyclic Aromatic Carbonyl Dyes

These dyes contain one or more carbonyl groups linked by a quinonoid system. They tend to be relatively large molecules built up from smaller units, typically anthraquinones. Since they are applied to the substrate (usually cellulose) by a vatting process, the polycyclic aromatic carbonyl dyes are often referred to as anthraquinonoid vat dyes. 

Although the polycyclic aromatic carbonyl dyes cover the entire color range, only the blues, browns, greens, and blacks are important commercially. Typical dyes are the blue indanthrone (6), C.I. Vat Brown 3 (7), C.I. Vat Black 27 (8), and the C.I. Vat Green 1 (9), probably the best known of the polycyclic aromatic carbonyl dyes. 

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Indigoid Dyes Like the anthraquinone. benzodifuranone. and polycyclic aromatic carbonyl dyes, the indigoid dyes also contain carbonyl groups. They are also vat dyes. 

Aromatic hydrocarbons, carbonyl compounds (DNPH derivatives), herbicides, hydrazines, insecticides, metal ions, fat-soluble vitamins, lipids, lipophiUc dyes, polycyclic aromatic hydrocarbons (PAHs)... 

Dyes based on anthraquinone and related polycyclic aromatic quinones are of great importance. Many of the most lightfast acid, mordant, disperse, and vat dyes are of this kind. The chromophore is the carbonyl group. 

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