GB462176A - Manufacture of azo dyestuffs - Google Patents

Abstract

Monoazo dyes are made by coupling, in aqueous alkaline medium, a diazotized amine of the benzene series having a nuclear alkyl group of 8 to 20 carbon atoms with an aminonaphthol sulphonic acid of the general formula <FORM:0462176/IV/1> where X = alkyl or hydroxyalkyl (C1 to C4) and Y = H, hydroxyalkyl, acyl, aroyl or arylsulphonyl. They dye animal fibres in brown shades fast to milling. Dyes from the following components are described; diazo components; p-dodecylaniline and its o- and m-sulphonic acids, p-cetylaniline, p-decylaniline, 1-methyl-5-dodecyl-4-aminobenzene; coupling components: the N-b -hydroxyethyl-, N-b -hydroxyethyl-N-n-butyryl-, N-benzoyl-N-b -hydroxyethyl-, N-acetyl-N-b -hydroxyethyl-, N-methyl-, N-acetyl-N-methyl-, N-methyl-N-b -hydroxyethyl-, N-p-toluenesulphonyl-N-b -hydroxyethyl- and N-b b <1>-dihydroxydiethyl-derivatives of 2 : 8 : 6-acid. Specification 443,835 is referred to. 2-N-acetyl-, N-butyryl- and N-benzoyl- N-b -hydroxyethylamino - 8 - naphthol - 6-sulphonic acids are made by treating a neutral aqueous solution of 2-N-b -hydroxyethylamino-8 - naphthol - 6 - sulphonic acid with acetic anhydride, n-butyric anhydride and benzoyl chloride respectively. p-Dodecylaniline-m-sulphonic acid is made by sulphonating p-dodecylaniline with 100 per cent sulphuric acid. p-Dodecylaniline - o - sulphonic acid is made by sulphonating p-dodecylaniline with chlorsulphonic acid in tetrachlorethane.