GB447775A - Process for the manufacture of azodyestuffs - Google Patents

Abstract

Azo dyes containing copper in a complex form are made by coupling a mono-azo dye of the formula <FORM:0447775/IV/1> (in which x=hydroxyl, alkoxy, halogen or carboxyl, y=hydroxyl amino or substituted amino, one z means the same as y and the other z stands for hydrogen or any substituent, and in which R means a benzene or naphthalene radicle and R and R<1> may contain further substituents), with a diazo compound containing only once the grouping --N=N--, if desired, coupling the disazo dye with a further diazo compound, and transforming the dyestuff by a wet process either prior or subsequent to the final coupling into the copper complex compound of the corresponding o-hydroxy- or o-carboxy azo dye. They dye leather, and animal and vegetable fibres in brown shades. The following dyes are described in examples: (1) 2-anisidine-4-sulphonic acid --> resorcinol (coppered) \sM m-nitroaniline or 4-nitro-1 : 3-phenylenediamine; (2) 2-anisidine-4-sulphonic acid \sQ resorcinol treated with copper ammonia solution; (3) 6-chloroaniline-3-sulphonic acid --> resorcinol (coppered) \sM dehydrothiotoluidine sulphonic acid; (4) 5-nitro-2-anisidine-4-sulphonic acid --> resorcinol (coppered) \sM p-chloraniline; (5) the second disazo dyestuff in (1) coupled with diazotized 2-anisidine-4-sulphonic acid or 4-nitroaniline-3-sulphonic acid; (6) 2-anisidine-4-sulphonic acid \sQ resorcinol \sM p-nitroaniline treated with copper ammonia solution; (7) 2-chloraniline-4-sulphonic acid --> resorcinol (coppered) \sQ p-nitroaniline and dehydrothiotoluidine sulpho acid. Specification 297,003, [Class 2 (iii)], is referred to. The Specification as open to inspection under Sect. 91 comprises the coupling of the monoazo dyes of the above formula with a diazo compound suitable for preparing azo dyes with the exception of a diazoazo compound, if desired, coupling the disazo dye with a further diazo compound, and transforming the dyestuff either prior or subsequent to the final coupling into a heavy metal complex compound. Examples of the following dyestuffs are given: (1) 6-chloro-2-aminophenol-4-sulphonic acid --> resorcinol \sM dehydrothiotoluidine sulphonic acid or 4<1>-nitro-4-aminodiphenylamine sulpho acid treated with chromium formate; (2) anthranilic acid --> m-aminophenol (chromed) \sM p-nitroaniline-3-sulphonic acid; (3) nitro-1-amino-2-naphthol-4-sulphonic acid --> resorcinol (chromed) \sM naphthionic acid; (4) the dyestuff of (3) coupled alkaline with diazotized p-nitroaniline; (5) 4-nitro-2-aminophenol - 6 - sulphonic acid \sQ m - phenylene diamine treated with chromium sulphate. This subject-matter does not appear in the Specification as accepted.