Patent GB-735120-A (GB)
Title: Improvements in the production of copper-containing disazo and polyazo dyestuffs
IPC: C09B35/00
Filed: 1952-08-29
Abstract: Water-soluble copper-containing dis- and poly-(o,o1-dihydroxy-azo) dyestuffs are made by subjecting to oxidizing coppering bis-(orthomonohydroxy-azo) dyestuffs obtained by coupling tetrazotized diamines of formula H2N-R1-X-R2-NH2 (in which R1 and R2 are aromatic groups of the benzene series free of hydroxy groups and in which at least one ortho-position to each amino group is unsubstituted and X is a mono- or poly-atomic bridge) with two molecules of one, or one molecule of each of two different, phenolic or enolic compounds which couple in ortho-position to the hydroxyl group and contain no further hydroxyl group in the same nucleus, whereby the tetrazo and/or phenolic and/or enolic components contain at least one sulphonic acid group.  Diamines specified are 3,31-, 3,41- and 4,41 - diamino - diphenyl - ether, -sulphide, -sulphone, -methane, -urea, -thiourea, -cyclohexane and -amine, -triphenylamine, -methyl-diphenylamine, -benzyldiphenylamine, -benzophenone, -benzanilide, -azobenzene, -azoxybenzene, -stilbene and -dibenzyl and nitro, halogen, sulphonic, e.g. 4,41-diamino-stilbene-2,21-disulphonic acid and carboxylic acid substitution products thereof and the condensation product of one mol. of benzaldehyde with two mols. of aniline.  Specified coupling components are p-cresol, p-tert.-butyl phenol, 1-methyl - 4 - hydroxynaphthalene, 1 - hydroxynaphthalene - 4 or 5-mono- or -3,6-, 3,8- or 4,8-di-sulphonic acid, 2-hydroxynaphthalene and its mono-, e.g. -4- and di-sulphonic acids, e.g. the 3,6-acid, 1-acetylamino-8-hydroxynaphthalene-3,6-disulphonic acid, 1-(21,51-dichlorbenzoyl) - amino - 8 - hydroxy - naphthalene - 4,6 - disulphonic acid, 1 - (p - toluenesulphonyl) - amino - 8 - hydroxynaphthalene - 4 - sulphonic acid, 2,8 - dihydroxynaphthalene - 6 - sulphonic acid, 2 - phenylamino - 5 - hydroxynaphthalene-7-sulphonic acid, 1-phenyl-3-methylpyrazolone-(5) and its sulphonic acids, e.g. 1-(21-methyl-41-sulphonic acid) phenyl-3-methylpyrazolone-5, acetoacetic acid and benzoylacetic acid anilides and monoazo derivatives of m-aminophenol.  Coppering may be effected by treatment with copper salts in neutral or weakly acid medium with hydrogen peroxide, perborates, percarbonates, organic peracids or acyl peroxides; with molecular oxygen, e.g. air, with copper salts and compounds which readily form peroxides; or with oxygen, e.g. air, at about 100-150 DEG  C. under pressure in the presence of metallic copper and preferably also with copper salts and, advantageously, polynuclear quinones. One or both copperable groups may be coppered.  Fibres, especially of regenerated cellulose or leather, are dyed red to blue shades. The dyestuffs may be decoppered and the resulting copper-free dyes converted into other metal dyestuffs, e.g. into Cr, Co or Fe complexes.  Examples describe the use of certain of the components specified above and the hydrolysis of the acetylamino group in a copper dyestuff obtained by the use of 1-acetylamino-8-hydroxynaphthalene - 3,6 - disulphonic acid. Specifications 660,447 and 721,495 are referred to.