Patent GB-828826-A (GB)
Title: Improvements relating to metallisable polyazo dyestuffs and their use
IPC: C09B45/24
Filed: 1956-09-12
Abstract: The invention comprises dyestuffs of formula <FORM:0828826/IV(c)/1> where A is the residue of a starting component, B is the residue of a mononuclear benzene or naphthalene middle component containing the azo link in the p-position and the substituents -OR in the o-position to the second azo group, R is a methyl, ethyl or carboxymethyl group, n is 1-3, Y is a direct link or -NH-CO-(NH)m-Ph-, where m is 0 or 1 and Ph is a m- or p-phenylene radicle, Z is an acylacetylamino or a 5-pyrazolone residue bound at the amide N atom, or in the 1 position, to Y respectively and is bound at the a -carbon atom, or in the 4-position, to the azo group respectively, D is the residue of a diazo component of the benzene or naphthalene series containing a metallizable group oto the azo link and residue E contains the OH group o to the azo group, the products having at least one SO3H group.  They are made by alkaline coupling, e.g. in the presence of sodium carbonate, ammonia or magnesium oxide and optionally a tertiary nitrogen base, a diazo compound of a p-aminoazo dyestuff which contains a methyl, ethyl or carboxymethyl group in the o-position to the diazotized amino group, the component containing these groups belonging to the benzene or naphthalene series, with an appropriate naphtholic azo dyestuff.  The naphtholic azo dyestuff is made by coupling appropriate naphthalenic acylacetyl compounds or 1-arylpyrazolones with the required diazo compound in a weakly acid to weakly alkaline medium.  Specified components corresponding to D contain groups such as alkyl, nitro, alkoxy, acylamino, urea, sulphonic acid, halo, sulphonamide, N-substituted sulphonamide and carboxylic acid amide groups and, as metallizable groups, hydroxy and carboxy groups.  Preferred for D are anthranilic acid residues. Compounds derived from acylacetylamines are also preferred.  The acylacetyl compounds and pyrazolones may be made by treating amino naphthols or their sulphonic acids, or aminobenzoyl or aminophenyl carbamyl derivatives with acylacetic acid esters or diketene, before or after diazotizing their amino groups and reducing to the corresponding hydrazine.  2-Amino-6-naphthol-8-sulphonic acid is the preferred naphthol although others are specified.  The starting p-aminoazo dyestuffs may contain halo, alkyl, hydroxy, alkoxy, acylamino, nitro, carboxyl, sulphonic acid, carbamide and sulphonamide groups in addition to the specified metallizable groups. They are made by conventional diazotization and coupling processes. Indicated for their diazo moiety are benzene, naphthalene, stilbene or heterocyclic compounds, representative of many specified being aniline - 3 - sulphonic acid, 5 - (31 - aminobenzoyl) - amino - 2 - phenol - 1 - carboxylic acid, dehydro-p-toluidine monosulphonic acid, 4 - nitro - 41 - aminostilbene - 2,21 - disulphonic acid and 4-amino-2-methyl-1,11-azobenzene-21-sulphonic acid. Representative of specified components corresponding to b  are 5-methyl-2-methoxy - aniline, 2 - carboxymethoxy - 1 - naphthylamine and 2-ethoxy-1-naphthylamine-6 sulphonic acid. The dyestuffs, or alkali metal or ammonium salts, dye cellulosic materials which may be after-coppered.  If the dyestuffs contain at least two sulphonic acid groups per molecule they may be coppered in substance.  Examples and tables are given illustrating the preparation of the dyestuffs and their use in dyeing processes.  Specification 755,571 is referred to.