Patent GB-888582-A (GB)
Title: New azo-dyestuffs and process for their manufacture
Filed: 1958-11-03
Abstract: Compounds of formula <FORM:0888582/IV (b)/1> are novel azo dye intermediates (see Group IV (c)) made by reducing the corresponding nitro-compounds under conditions so that any acid residues are not split off.  The nitro-compounds are made by condensing 1 mol of a nitroaldehyde with 2 mols of b -chloropropionamide or acrylamide in the presence of a strong acid, especially sulphuric or hydrochloric acid.  In Examples (1) 3-aminobenzylidene-bis-(b -chloropropionyl)-amide and (2) 3-aminobenzylidene-diacrylamide are made by reducing the corresponding nitro-compounds with hydrogeu in the presence of Raney nickel and a solvent of alcohol and dimethylformamide.ALSO:The invention comprises azo-dyes which contain at least one group imparting solubility in water and at least one residue of formula <FORM:0888582/IV (c)/1> where R is a vinyl or b -halogenethyl group.  The dyes are made by conventional processes of diazotisation and coupling.  Specified watersolubility imparting groups are sulphonamide, methyl-sulphone, carboxy and sulphonic acid groups.  Preferably at least two water-solubility imparting groups are present.  The group of the above formula may be bound to the dye molecule via an alkylene or arylene residue but is preferably bound directly to an aromatic residue of the dye molecule.  Indicated as further substituents in the dye molecule are, e.g. halo, nitro, acylamino, alkyl and alkoxy groups.  Examples of specified diazo components are <FORM:0888582/IV (c)/2> and <FORM:0888582/IV (c)/3> where R is vinyl or b -chloroethyl, aniline-2-sulphonic acid, 2 - methoxyaniline - 5 - sulphonic acid, 3-amino-2-oxybenzoic acid-5-sulphonic acid, 5-acetylaminoaniline-2-sulphonic acid, 1- and 2-naphthylamine-4-sulphonic acids, 1-(41-aminobenzoyl) - aminobenzene - 3 - sulphonic acid, 3-aminopyrene-5,10-disulphonic acid, 4-nitro-41-aminostilbene-2,21-disulphonic acid, 0-acyl derivatives of 1-amino-8-naphthol-4,6-disulphonic acid and dehydrothiotoluidine mono- or di-sulphonic acids.  Aminomonoazo dyes containing sulphonic acid groups may also be used as diazo components, e.g. those obtained by coupling a diazotised monoacyl derivative of an aromatic diamine with a coupling component containing a phenolic or ketomethylene group with subsequent hydrolysis of the acylamino group, e.g. hydrolysis of dyes from phenols, naphthols, 5-pyrazolones, barbituric acids, hydroxyquinolines, b -ketocarboxylic acid derivatives and diazotised monoacyldiamino-benzenes and -stilbene disulphonic acids. Aminomonoazo dye diazo components may also be used in which the amino group is in the coupling component moiety. Representative of indicated coupling components for the final dyes are N-sulphatoethyl aniline, salicyclic acid, 1-naphthylamine3,8-disulphonic acid, 1- and 2-naphthol-4-sulphonic acids, 1,8-dihydroxynaphthalene-3,6-disulphonic acids, 1-amino-8-naphthol-2,4-disulphonic acid, N-acyl derivatives of aminonaphthol sulphonic acids in which the acyl radical, is, e.g. acetyl, butyryl, chloracetyl, nitrobenzoyl, 31-aminobenzoyl, ethanesulphonyl, chlorobenzenesulphonyl and carbethoxy, acetoacetic acid arylides, pyrazoles, barbituric acids, hydroxyquinolines and <FORM:0888582/IV (c)/4> and <FORM:0888582/IV (c)/5> where R is a vinyl or b -chloroethyl group.  The dyes especially colour polyhydroxylated fibres such as cellulose, regenerated cellulose, linen, cotton and polyvinyl alcohol.  Preferably, when printing, processes are used in which fixation is accomplished with a strong alkali.  Dyes which have at most two sulphonic acid groups, and preferably a single acid group imparting watersolubility, dye and print, from a weakly alkaline bath, nitrogenous textile materials, e.g. leather, silk and especially wool, as well as superpolyamide or -urethane fibres.  Examples are provided of the preparation of the dyes and their use in dyeing or printing cotton in red and yellow shades.