Patent GB-774884-A (GB)
Title: Improvements relating to metallisable monoazo dyestuffs and complex chromium compounds thereof, and their use
IPC: C09B45/16
Filed: 1954-07-16
Abstract: 5 - methyl -, ethyl -, vinyl - or chlormethyl-2-amino-1-phenols are made by treating the corresponding 4 - sulphonyl benzene - 1 - diazonium compounds with hydroxylamine-o-sulphonic acid to form the corresponding 4-sulphonyl-1-azidobenzenes which rearrange in concentrated sulphuric acid.  The products may be diazotized to the diazoxides which are also obtained by neutralizing a mineral acid solution of the corresponding 4-sulphonyl-2-nitrobenzene-1-diazonium compounds, advantageously in the presence of naphthalene sulphonic acids, the neutralization leading to the replacement of the nitro group by a hydroxy group. Specifications 737,189, 774,885 and 774,886 are referred to.  Reference has been directed by the Comptroller to Specifications 637,404, [Group IV (c)], and 737,619.ALSO:The invention comprises dyestuffs of formula <FORM:0774884/IV(b)/1> where X is a methyl, ethyl, chloromethyl or vinyl group, B is the residue of a coupling component containing OH ortho to the azo link but containing no water-solubilizing groups which dissociate acid in neutral water and A may contain non-salt forming groups e.g. chlorine and methyl groups.  The invention also includes dyestuffs of formula (F-Cr-F1)-M where M is an alkali metal or ammonium cation; F1 is a co-ordinated dyestuff of the above formula and F has the same significance as F1 or is a co-ordinated o, o - dihydroxy monoazo dyestuff of the benzene-pyrazolone series containing no water-solubilizing groups which dissociate acid in neutral water. The metal-free dyestuffs are made by coupling component B with diazoxides corresponding to A advantageously in the presence of compounds such as pyridine bases, soap, tetrahydronaphthalene sulphonic acid and an alkali metal salt thereof.  The dyestuffs are chromed in conventional fashion, optionally in admixture with an appropriate o, o - dihydroxy azo dyestuff, so that at least one chromium metal atom is bound in complex union with two dyestuff molecules.  Indicated azo components are phenols, naphthols, acylacetic acid arylamides, 3 - alkyl - 5 - pyrazolones and 2,4 - dihydroxyquinolines which may contain halogen, alkyl, alkoxy, acylamino, sulphonamide, N - substituted sulphonamide and alkyl and aryl sulphonyl groups.  Complex chromium compounds produced in an acid medium when used as textile dyestuffs may be treated before or after isolation with alkaline agents such as alkali metal hydroxides and carbonates and the isolated dyestuff may be mixed with small amounts of salts such as alkali metal borates, carbonates and polyphosphates and trisodium phosphate optionally with wetting and dispersing agents.  The chromed dyestuffs dye natural and synthetic polypeptide fibres from a neutral to weakly acid bath.  In examples illustrating the preparation of the dyestuffs the diazo components used are 2 - amino - 5 - methyl-, -ethyl-, vinyl- and -chloromethylsulphonyl - 1 - phenol and 6 - nitro - 4 - methyl - and - chloro -2 - amino - 1 - phenol, the coupling components used being 1 - (21, 31 - and 41 - chloro - phenyl)-, - phenyl -, - (41 - methylphenyl) -, -(31 - sulphdimethylamidophenyl) -, - 31 - sulphamido - 41 - methylphenyl) - and -(21 - methyl - 51 - methylsulphonylphenyl) - 3 - methyl - 5 - pyrazolones, acetoacetic acid anilide and o - chloranilide, 2 - naphthol, 1 - acetylamino - 7 - naphthol, 3,4 - dimethyl - 1 - phenol and 3-methoxy - 4 - methyl - 1-phenol and the chromium complexes of the products are used to dye wool in red shades.  An example of dyeing wool using an unmetallized dye is also provided a bluish-grey tint being obtained. Specifications 737,189, 774,885 [Group IV(b)] and 774,886 are referred to.  Reference has been directed by the Comptroller to Specifications 637,404 and 737,619.