GB642592A - Manufacture of dyestuffs of the anthraquinone series - Google Patents

Abstract

1.4-Diaminoanthraquinones in which the amino groups are free or contain an aliphatically bound residue and which contain an azomethine group in 2-position are made by (1) treating such a 1.4-diaminoanthraquinone having a methyl or aldehydo group in 2-position so as to convert said methyl or aldehydo group to azomethine by a method known to be capable of such conversion, e.g. by heating a methyl body with nitrobenzene in presence of aniline, or by heating an aldehydo body with an amine; (2) by heating a 1-amino-2-azomethine-4-nitro- or halogen-anthraquinone with an aliphatic amine or with a sulphonic acid amide, followed by hydrolysis if the amide is used; (3) by heating a 1-amino-2-aldehyde-4-nitro-or halogen-anthraquinone with an aliphatic amine. Aliphatically bound residues specified are methyl, ethyl, b -oxyethyl, propyl, isopropyl, butyl, hexyl, cyclohexyl, and aralkyl. Amines specified are aniline, p-phenylene diamine, 1 - amino - 4 - dimethylaminobenzene, butylamine, ethanolamine, cyclohexylamine, benzylamine. The products dye nylon and cellulose esters and ethers blue shades. In examples: (1) 1.4 - diamino - 2 - methylanthraquinone is condensed with aniline to give the 2-anil; (2) 1.4-diaminoanthraquinone-2-aldehyde is condensed with aniline, p-phenylene diamine, 2.5-dimethyl-1.4-phenylene diamine, butylamine, ethanolamine, hexahydroaniline or benzylamine; (3) 1-amino-4-nitroanthraquinone-2-aldehyde is condensed with ethanolamine; (4) 1 - amino - 4 - bromanthraquinone-2-anil is condensed with p-toluene sulphonamide, followed by hydrolysis with 90 per cent sulphuric acid.