Patent GB-691686-A (GB)
Title: Process for the improvement of fastness properties of dyeings and printings producedfrom water-soluble dyestuffs
Filed: 1949-11-22
Abstract: Compositions for use in improving the fastness of dyeings comprise, in the dry form or in solution, a water-soluble copper compound (preferably complex) and a condensation product of an aldehyde with a nitrogen compound containing at least once the grouping <FORM:0691686/IV (a)/1> which condensation product has been produced in the presence of acid in an amount of 0.1-1 equivalent for 1 mol. of nitrogen compound.  The liquid compositions, when the copper compound is an ammonia or amine complex, are prepared by dissolving in water in any suitable sequence a non-complex copper salt, the condensation product, and either ammonia, or a mixture of an ammonium salt and an alkali metal carbonate, or a complex-forming amine. Preferred condensation products are those obtained by condensing 1 mol. of dicyandiamide (preferably by heating under pressure) with 2-4 mols. of formaldehyde in the presence of 1/10 -\ba1/2 mol. of a lower fatty acid (e.g. with fatty acid (e.g. with 2-3 mols. of formaldehyde in the presence of 1/6 -\ba1/2 mol. of acetic acid).  In examples: (1) 1 mol. of dicyandiamide is heated with 2.24 mols. of formaldehyde (aqueous solution) in the presence of 0.17 mol. of acetic acid; the product and copper acetate are dissolved in water; (2) the dicyandiamide in (1) is replaced by a mixture of biguanide nitrate and guanidine nitrate obtained by heating dicyandiamide with ammonium nitrate, and the proportion of acetic acid is increased; (3) the proportion of formaldehyde in (1) is increased to 3 mols.; (4) the proportion of formaldehyde in (1) is reduced to 2 mols. and the proportion of acetic acid doubled; (5) the condensation product of (1), copper acetate and ammonia are dissolved in water; alternatively the first two ingredients are mixed dry, the mixture dissolved in water and the ammonia added; the dicyandiamide may be replaced by biguanide and the copper acetate by copper formate, sulphate, chloride or nitrate; (9) the proportion of acetic acid in (3) is increased to 0.2 mol. and the heating is effected in a closed vessel; (10) the condensation product of (1), copper acetate, ammonia, ammonium acetate and dimethylolurea are dissolved in water.  Other compounds specified for use in the preparation of the condensation products are: acetaldehyde; dicyandiamidine, guanidine, acetoguanide, alkyl- and aryl-biguanides, di- and other poly-biguanides; formic, sulphuric and hydrochloric acids.ALSO:The fastness properties of dyeings or prints with direct dyestuffs which are water-soluble owing to the presence of sulphonic acid or carboxyl groups, and which are capable of forming complex copper compounds or already contain copper in complex combination, are improved by treatment with an aqueous solution of a condensation product of an aldehyde with a nitrogen compound containing at least once the grouping <FORM:0691686/IV (c)/1> which condensation product has been produced in the presence of acid in an amount of 0.1-1 equivalent for 1 mol. of nitrogen compound, and simultaneous or subsequent treatment with a water-soluble copper compound, preferably a water-soluble complex copper compound such as those containing ammonia or amines or derived from hydroxycarboxylic acids.  Suitable condensation products are those enumerated in Specification 673,711, and the same condensation products are used in the examples, in which they are applied to dyeings on cotton with various disazo and trisazo dyes or mixtures thereof, the following copper compounds being also employed: copper acetate and cuprammine acetate, formate, sulphate, chloride or nitrate.