MONOAZO PYRAZOLE DYESTUFFS

摘要

1399585 Monoazo pyrazole dyestuffs BAYER AG 10 Aug 1973 [12 Aug 1972] 37949/73 Heading C4P [Also in Division C2] A monoazo dyestuff has, in the form of the free acid, the formula in which R 1 is H, alkyl, cycloalkyl, aralkyl or aryl, R 2 is a sulphoalkyl, aryl or alkylaryl group, or a sulphato-alkyl group, R 3 is alkyl or aryl, -COOH, carbamoyl or a carboxylic ester group, R 4 is H, alkyl, cycloalkyl, aryl or aralkyl, or the radical of a heterolyclic compound, X is H, halogen, -CN, alkyl, alkoxy, -CF 3 , -NO 2 , carbamoyl or carboxylic ester group, and Y is H, halogen, alkoxy or acylamino. The dyes may be made by diazotization and coupling or by esterifying an aliphatic hydroxyl group in the azo compound with sulphuric acid. They give yellow or greenish-yellow shades with polyamide fibres, particularly poly-#-caprolactam or condensation products of adipic acid and hexamethylene diamine.