GB398163A - Dyeing process - Google Patents

Abstract

Azo dyes are made on the fibre by coupling an arylamide of 2 : 3-oxynaphthoic acid with the tetrazo compound of a diamine obtained by condensing an o-alkyloxyaniline or a derivative thereof (2 mols.) and an aromatic aldehyde (1 mol.), the components being devoid of water-solubilizing and nitro groups. Claret shades fast to kier-boiling and chlorine are obtained. In an example, cotton is impregnated with the a -naphthylamide and developed with tetrazotized 4 : 4<1>-diamino-2 : 2<1>-dimethyl-5 : 5<1>-dimethoxy-triphenylmethane. In a table the following components are also specified : 3 : 3<1>-dimethoxy- and 3 : 3<1> - 3<11>-trimethoxy-4 : 4<1>-diaminotriphenylmethane, 2<11>-chloro-2 : 2<1>-dimethyl-5 : 5<1>-dimethoxy-4 : 4<1>-diaminotriphenylmethane: the 4-brom-o-anisidide, anilide 5-chlor-o-toluidide, o- and p-anisidide and b -naphthylamide of 2 : 3-oxynaphthoic acid. Specification 17279/13, [Class 15 (ii), Dyeing, Processes &c. for], is referred to. Samples have been furnished under Sect. 2 (5) of the following couplings on cotton: (1) and (2) 2 : 2<1>-dichlor-4 : 4<1>-diamino-5 : 5<1>-dimethoxy-triphenylmethane \sQ 4-brom-o-anisidide or b -naphthylamide, (3) 2 : 2<1>-dibrom-4 : 4<1>-diamino-5 : 5<1>-dimethoxytriphenylmethane \sQ 4-brom-o-anisidide. 4 : 4<1>-Diaminotriphenylmethanes above referred to are made from the appropriate aldehyde and amine in the presence of hydrochloric acid.