Patent GB-963070-A (GB)
Title: Improvements relating to metal-containing reactive disazo dyestuffs, and cellulose-containing material dyed or printed therewith
IPC: C09B62/012
Filed: 1961-03-17
Abstract: The invention comprises reactive dyes of formula <FORM:0963070/C4-C5/1> where R1 is the residue of an azo component, R2 is the residue of an azo component containing -OMeadjacent the double bond, X is an acyclic substituent having at least one mobile halogen atom or one mobile sulphonic acid ester group, the latter being attached to the b  carbon atom of an aliphatic chain bound to the dye residue via an SO2 or SO2NH link, Me is a metal of atomic number 24-29, possibly co-ordinated with other complex formers, n is 1 or 2 and m 1 to 4.  The dyes may be made by conventional metallization processes from the corresponding disazo dyes or by introducing group X into corresponding dyes where X is an amino group. Representative of indicated residues for X, when halogen, are those of chloracetic, b -brompropionic, g -chlorcrotonic, bromomaleic, b -chlorethane sulphonic and a ,b -dichlorpropionic acid, X being attached to the dye residue via an amino group.  Other indicated values for X are sulphated b -hydroxyethylsulphonyl and sulphonic acid N-b -hydroxyethylamide groups and sulphonic acid -N-b -chloro- and -bromo-ethylamide groups.  Copper, chromium and cobalt are specified metals, copper being preferred. Coloured or uncoloured compounds co-ordinated with the heavy metal, e.g. aromatic o-hydroxy-carboxylic acids or o,o1-dihydroxy, o-hydroxy-o1-carboxy-or o-hydroxy-o1-amino-azo dyes, may be retained in the product.  The metal-free starting azo dyes are made in conventional fashion by coupling appropriate components with tetrazotized 1-hydroxy- or -chloro-2, 6-diaminobenzene-4-sulphonic acid.  X may be present in the starting dyes, obtained as above, or introduced afterwards, e.g. by acylating an amino group present in the dye, or by sulphating an appropriately placed hydroxyl group. Indicative of the azo components specified are m-toluidine, aminohydroquinone dimethyl ether, m-phenylenediamine, a -naphthylamine, 1-amino-5-naphthol-7-sulphonic acid and 1-(31- or 41 - aminophenyl) - 3 - methyl - 5 - pyrazolone. Amino groups in the azo components may be aminobenzoylated or treated with m- or p-nitrobenzoyl chloride and then reduced to the corresponding amino compounds.  The acylatable amino groups are formed, after coupling, by saponifying acylonuric groups or aminomethylene sulphonic acid groups.  Preferred are unsymmetrical o,o1-dihydroxy disazo dyes in which only one of R1 and R2 has an acylamino group with a mobile halogen atom.  For pad dyeing and printing cellulose fibres the dyes, as their alkali metal salts, should be easily soluble and components should be chosen accordingly. Thus, 1:1 copper dyes should have at least 2, preferably 3-5, sulphonic acid groups and 1,2-chromium or cobalt dyes generally need two sulphonic acid groups only. The metal dyes dye and print natural and synthetic polyamide fibres but are especially useful for natural and regenerated cellulosic fibres, e.g. cotton, viscose rayon, staple fibre, jute, hemp, ranie, navy, brown- and violet-black and black shades being obtained.  Dyeings on cellulose are fixed with acid-binding agents at elevated temperatures.  Acid-binding agents may also be present in the impregnating baths, the dyeing being developed at e.g. 100-160 DEG  C. Numerous examples are provided of the preparation of the dyes and their use in colouring cotton.