Patent GB-953253-A (GB)
Title: Process for dyeing and printing fibrous materials
IPC: D06P1/56
Filed: 1961-02-23
Abstract: Fibrous materials are dyed or printed by applying an aqueous preparation containing 1 : 2-chromium or 1 : 2-cobalt complex azo or azomethine dyes which contain at least one acid group imparting solubility in water and at least one acid amide group as hereinafter defined as well as aminoplasts that are soluble or at least dispersible in water thereafter curing the material in the presence of an acidic catalyst.  The fibrous materials may be leather, paper, glass fibres and especially textile materials of cellulose acetate, polyamide, polyurethane, polyacrylonitrile, polyester, natural or regenerated cellulose particularly cotton. The complexes may contain the heavy-metal atom in complex union with two molecules of one dyestuff or one molecule each of different dyestuffs or with one molecule of a dyestuff and one molecule of a colourless complex former.  The dyes may contain one or more than one azo or azomethine group.  The acid groups may be -COOH, -SO3H as well as -OSO3H groups and the complex may contain up to four such groups.  The acid amide group may be a -CONH2 or -SO2NH2 group or they may bear substituents at the N atom such as a lower alkyl or hydroxyalkyl group or such a group and a cyclohexyl, benzyl or phenyl radical in which the benzene nuclei may be further substituted e.g. with hydroxyl groups, or the amide nitrogens may form part of a heterocycle such as morpholine or piperidine as well as the amide groups derived from acids such as formic, acetic or benzoic acid bound to the dyestuff molecule via the N atom or alternatively a group of the type -SO2-NH-CH-CH2-O-SO3H. The dyestuffs may be further substituted for example with halogen atoms or aromatically bound hydroxy, alkyl, alkoxy or nitro groups. Specified complex forming groups are o,o1-dihydroxyazomethine, o-carboxymethoxy-o1-hydroxyazo, o-carboxy-o1-hydroxyazo, o-carboxy-o1-aminoazo, o-hydroxy-o1-aminoazo or, preferably o, o1-dihydroxyazo.  A large number of suitable aminoplasts is specified, the preferred compounds being the methylol compounds of urea and melamine or derivatives thereof which may be etherified with lower alcohols.  In addition to the at least water-dispersible aminoplast there may also be included in the aqueous preparation water-insoluble aminoplast and lattices of polymers, particularly polyethylene as a softener or polymers containing groups which can cross-link with the aminoplasts (long list given).  Specified acidic catalysts are ammonium sulphate, ammonium chloride, diammonium phosphate, ethanolamine hydrochloride, magnesium chloride, zinc nitrate, zinc fluoborate and ammonium silicofluoride.  The aqueous preparation may also contain wetting or dispersing agents, thickeners such as oil-in-water emulsions, starch, tragacanth or methylcellulose and hydrotropic agents such as urea.  The preparations are preferably applied in a continuous manner, e.g. by padding.  A drying step is advantageously introduced before the curing which may be effected at 120 DEG -180 DEG C.  After curing the material may be washed and rinsed.  According to the composition of the aqueous preparation additional effects of crease and shrink resistance, permanent calender effects, improved handle or water repellancy may be obtained.  Examples of dyeing and printing cotton and spun rayon are given in which a large number of dyes are used, representative of which are metal complexes of the dyes of the following formulae: <FORM:0953253/D1-D2/1>