3 , and its structure is 1-hydroxy-4-(p-tolylamino)-anthraquinone, or 1-hydroxy-4-[(4-methylphenyl)amino]-9,10-anthracenedione or 1-hydroxy-4-(4-methylanilino) anthraquinone. Solvent Violet 13 is used to dye hydrocarbon products like solvent s and petrol , thermoplastic s, synthetic resin s, e.g. polystyrene s, and synthetic fiber . It is also used in cosmetics , e.g. in hair and skin