GB466127A - Manufacture of monoazo dyestuffs - Google Patents

Abstract

Monoazo dyes are made by coupling a diazotized amino-carboxylic ester of the formula NH2--Ar--COOR where Ar= a phenyl residue and R=a long chain aliphatic hydrocarbon radicle of at least 10 and not more than 20 carbon atoms, with a coupling component devoid of long chain aliphatic hydrocarbon residues and having at least one SO3H or COOH group. They dye wool in various shades fast to washing and milling or fulling. In examples, dyes from the following components are specified: diazo components: dodecyl-m- or p-aminobenzoate, dodecyl-3-amino-4-methoxy-1-benzoate, dodecyl - 3 - amino - 4 - methyl - 1-benzoate, cetyl - m - aminobenzoate, dodecyl-2 - chloro - 5 - amino - 1 - benzoate, decyl-p - aminobenzoate; coupling components: naphthol sulphonic acids, aminonaphthol sulphonic acids or their N-substituted derivatives, naphthylamine sulphonic acids and sulphoarylpyrazolones, e.g. 2-naphthol-6 : 8-disulphonic acid, N-acetyl H- or K-acid, 1-(4<1>-sulphophenyl) - 3 - methyl - 5 - pyrazolone, 1 - (2<1> : 5<1> - dichloro - 4<1> - sulphophenyl) - 3 methyl - 5 - pyrazolone, H acid, N- b -hydroxyethyl - 2 : 8 : 6 - acid, 1 - naphthol - 3 : 6-disulphonic acid, 1-(4<1>-sulphophenyl)-5-pyrazolone - 3 : carboxylic acid, N - benzoyl H-acid, N-acetyl - N - b - hydroxyethyl-2 : 8 : 6-acid. Specification 314,768, [Class 2(iii)], is referred to. Aminocarboxylic esters of the above formula are made by condensing the corresponding nitroaroyl chloride with the corresponding long chain aliphatic alcohol in an inert solvent and reducing the nitroaryl carboxylic ester thus obtained. Alcohols specified are dodecyl, tetradecyl, hexdecyl, octadecyl and oleyl.