Reductive mixtures, printing pastes, printing colors and treatment baths

摘要

The dyeing of textile materials with vat or sulphur dyestuffs is characterized by the use of a reductive mixture, printing paste, printing colour or treatment bath which contains (a) at least one alkali metal, alkaline earth metal or ammonium salt of a hydroxy alkane sulphinic acid, preferably containing 1-4 carbon atoms or of an alkane sulphinic acid, preferably containing 1-4 carbon atoms which is substituted by a nitrogen-containing aliphatic radical and (b) at least one complex alkali metal cyanide of chromium, manganese, cobalt and/or nickel as a redox catalyst. Examples of (a) are compounds of the formula in which A is H or low alkyl preferably with 1-4 C atoms which in turn may bear a radical or the formula where D in both formulae is the radical of a salt of an alhanemlphinic acid with 1-4 C atosm of the formula where E is H or alkyl, G is H or alkyl, Z+ is a cationic radical of an alkali or alkaline earth metal or of ammonium, x is 0, 1 or 2, y is 1, 2 or 3 and the sum (x+y) is 3, p is 0, 1 or 2, q is 0, 1 or 2 and the sum (p+q) is 2. Specified metals from which the cations may be derived are Na, Mg, K, Ca and Ba. Also (a) may be formamidinesulphinic acid (thiourea dioxide). Specified (a) of the hydroxy alkane sulphinic acid type are: the Na, K, Ca, Ba and ammonium salts of 1-hydroxyethane sulphinic acid-(1), 1-hydroxypropane sulphinic acid-(1), 2-hydroxypropane sulphinic acid-(2), and 1-hydroxy-n-butanesulphinic acid-(1). Specified compounds of formula I are obtained by reacting ammonia or derivatives of ammonia which bear at least one hydrogen atom bound to the nitrogen atom with the Na, K, Ca, Ba or ammonium salts of linear or branched hydroxyalkane sulphinic acids with 1-4 C atoms bearing the -OH and the sulphinic acid group on the same carbon as specified above. Specified compounds (b) are of the formula: K3[Cr(CN)6], K3[Mn(CN)6], K4[Mn(CN)6], K2[Ni(CN)4],3H2O, K3[Co(CN)6], K4[Co(CN)6], Na2[Ni(CN)4],3H2O, Na4[Mn(CN)6], Na3[Mn(CN)6], K3[Mn(CN)5NO], Na2[Ni(CN)3NO], K4[Co(CN)5CO], K3[Cr(CN)5NH3], K3[Co(CN)5NO2], and Na5[Mn(CN)5SO3]. Compounds (b) may be employed in an amount 0,1-10% on the weight of compound (a) used. The reductive mixtures may be prepared in situ, for example by printing a fabric with a paste containing (a) and subsequently padding with a solution containing (b). Alternatively both (a) and (b) may be applied simultaneously, together with the dye or previously or subsequently. Discharge printing over direct and azo dyeings is described. The reductive mixtures may also be employed in bleaching processes. The textile materials specified are fibres, filements, threads, flock, woven and non-woven fabrics of natural or regenerated cellulose, cellulose acetate, polyamides and aromatic polyesters. Examples are given in which the following compounds (a) are employed in addition to those already listed: sodium and calcium hydroxymethanesulphinate, sodium and barium aminomethanesulphinate and compounds of the following formulae: Specifications 829,177, 829,936, 837,940 and 881,487 are referred to.