GB434243A - Improvements in the manufacture and production of azo dyestuffs - Google Patents

Abstract

Azo dyes are made by coupling aromatic diazo, diazoazo or tetrazo compounds free from sulphonic and carboxylic groups, but which may contain halogen, nitro or other substituents, with aromatic o-hydroxycarboxylic acid amides free from sulphonic and carboxylic acid groups which have no free p-position to the hydroxyl group and which contain attached to the nitrogen atom of the acid amide radicle at least one aliphatic radicle having more than five carbon atoms. They are soluble in hydrocarbons, alcohols, ethers, ketones, paraffin waxes, fats, waxes and oils and may be used for colouring these materials and in the manufacture of coloured nitrocellulose lacquers, films, candles, polishing-waxes, and shoe polishes. In an example, diazotized aniline is coupled with 2 : 3-oxynaphthoic acid dodecylamide in pyridine or in an aqueous suspension in presence of acetone and turkey red oil. Dyestuffs from the following components are also specified: p-toluidine, a -naphthylamine, aminoazobenzene, 2-amino-1 : 4-dimethoxybenzene, p-nitraniline, 1-amino-2-nitro-4-methylbenzene, dianisidine, 1-benzoylamino-2 : 5-diethoxy-4-aminobenzene, 1-amino-2-methoxydiphenylamine and 4 : 4<1> - diaminodiphenylamine; 1 - methyl - 4 - hydroxybenzene - 3-carboxylic acid decylamide, 2 : 3-oxynapthoic acid methyldodecylamide, 2 : 3-oxyanthracene carboxylic acid dodecylamide, 6-methoxy-2-naphthol-3-carboxylic acid oleylamide. o-Hydroxycarboxylic amides of the above kind are obtainable by condensing the acid, e.g. p-cresotinic acid, 2 : 3-oxynaphthoic acid, 2 : 3-oxyanthracene or 2 : 3-oxycarbazole carboxylic acids with primary or secondary amines having at least one aliphatic radicle containing more than five carbon atoms, such as hexylamine, dodecylamine, octodecylamine, oleylamine, methyldodecylamine, di-doceylamine, cyclohexyldodecylamine and hexylaniline or mixtures thereof. Such amines may be prepared according to Specification 421,718. The Specification as open to inspection under Sect. 91 comprises an example in which tetrazo dianisidine is coupled with 2 : 3-oxynaphthoic acid dodecylamide and b -naphthol in a mixture of pyridine and methanol. Other additional components specified are ethyl-b -napththylamine, p - cresol, p - cyclohexylphenol, 2 : 4-hydroxyquinoline, methylphenylpyrazolone and acetic acid anilide. This subject-matter does not appear in the Specification as accepted.