Patent GB-436588-A (GB)
Title: Process for the manufacture of heavy metal complex compounds of azodyestuffs
IPC: C09B45/01
Filed: 1934-04-05
Abstract: Metal complex compounds of azo dyes are made by treating with an agent yielding heavy metal, in substance or on the fibre, such azo dyes as contain in the radicle of the diazo component in o-position to the azo group an amino group in which the hydrogen atoms can be substituted by alkyl, aralkyl or acyl groups.  The starting materials may be obtained for example by coupling diazo compounds containing in o-position to the diazo group an amino group, both hydrogen atoms of which are substituted by alkyl, aralkyl or acyl groups, with coupling components or by coupling diazotized o-nitro- or o-halogen substituted amines with components and transforming the nitro or halogen into the amino group (cf. Specification 436,095).  Those metal compounds which are insoluble in water are valuable pigments. In examples: (1) the dyestuff 3-nitro-4-toluidine --> 1-(4<1>-sulphophenyl)-3-methyl-5-pyrazolone is reduced by means of a ferrous salt in alkaline medium to the corresponding o-aminoazo compound and treated with chromium formate; (2) the reduced dyestuff 3-nitro-4-toluidine --> the 3-methyl-5-pyrazolone from 2-naphthylamine-4 : 8-disulphonic acid is acetylated and p  chromed as above; the o-aminoazo dye may be after-chromed on the fibre or used in the single bath chroming process; (3) the reduced dyestuff 3-nitro-4-toluidine --> 1-(3<1>-sulphophenyl)-3-methyl - 5 - pyrazolone is benzoylated and chromed as in (1); (4) the reduced dyestuff 3-nitro-4-toluidine --> 1-(2<1>-sulphophenyl)-3-methyl-5-pyrazolone is p-toluenesulphonated and chromed as in (1); (5) the dyestuff 2 - dimethylamino - 1 - aminobenzene - 4 - sulpho acid --> b -naphthol is after-chromed in substance or on the fibre as above; (6) the reduced dyestuff 2-nitraniline-4-sulphonic acid --> b -naphthol is chromed as above; (7) the reduced and p-toluenesulphonated azo dye 3-nitro-4-toluidine --> 1-naphthol-4-sulphonic acid is similarly chromed; (8) the reduced dyestuff 3-nitro-4-toluidine --> 1-naphthol-3 : 7-disulpho acid; and (9) the dyestuff 1-dimethylamino-2-aminobenzene - 4 - sulpho acid --> 1 - phenyl3-methyl-5-pyrazolone are chromed as in (1). The properties of the chromium compounds of the following dyestuffs prepared in substance or on the fibre are given in a table: (1) 3-nitro-4-toluidine --> 1-(3<1>-sulphophenyl)-3-methyl-5-pyrazolone (reduced); (2) 3-nitro-4-toluidine --> 1-(2<1>-chloro-4<1>-sulphophenyl)-3-methyl-5-pyrazolone (reduced and p-toluenesulphonated); (3) 2 - nitro - 4 - chloraniline --> 1 - (4<1> - sulphophenyl) - 3 - methyl - 5 - pyrazolone (reduced); (4) 3-nitro-4-toluidine --> 1-methylpyrazolone from 2 - naphthylamine - 4 : 8 - disulpho acid (reduced and p-toluenesulphonated); (5)-(7) the reduced dyestuffs 2-nitroaniline-4-sulpho acid --> 1-phenyl-3-methyl-5-pyrazolone or acetoaceticanilide, o-nitroanilne --> chromopropic acid; (8) 3-nitro-4-toluidine --> 1-naphthol-4-sulpho acid (reduced and acetylated); (9)--(13) the reduced dyestuffs 3-nitro-4-toluidine --> 1-naphthol-5-sulpho or 3 : 6-disulpho acid, 4 - ethoxy - 2 - nitroaniline --> acetyl - 2 : 8 : 6-acid, 2-nitroaniline-4-sulpho acid --> p-cresol; (13)--(14) 3-nitro-4-toluidine --> 1-naphthol-3 : 7-disulpho acid (reduced and acetylated or p-toluenesulphonated); (15)--(16) the iron compounds of the reduced dyestuff 3-nitro-4-toluidine --> 1-phenyl or 1-(2<1>-chloro-4<1>-sulphophenyl) - 3 - methyl - 5 - pyrazolone (the former colours zapon lacquer brown).  Samples have been furnished under Sect. 2 (5) of (1) the iron compound of the reduced dyestuff 3-nitro-4-toluidine --> 1-phenyl-3-methyl-5-pyrazolone, (2) the chromium compound of the reduced and benzylated dyestuff 4-ethoxy-2-nitroaniline --> 1-(3<1>-sulphophenyl)-3-methyl-5-pyrazolone.  1 - Dimethylamino-2-aminobenzene-4-sulphonic acid is made from 1-chloro-2-nitrobenzene-4-sulphonic acid and dimethylamine and reducing.