| 摘要 |
1,252,908. Treating textiles. CIBA (A.R.L.) Ltd. 6 June, 1969 [25 June, 1968; 20 Dec., 1968], Nos. 30226/68 and 60779/68. Heading D1P. In a process for treating textiles a resin forming composition containing:- i) an aqueous, non resinous solution of ureaformaldehyde condensation products prepared as described below, having a molar ratio of urea: formaldehyde of between 1:4 and 1:10, and a total concentration of constituents of between 40 to 90% by weight. ii) urea in a quantity to bring the molar ratio of urea: formaldehyde in the final composition within the range 1:1.3 to 1:2. iii) water in a quantity to bring the total concentration of the above constituents within the range 10 to 85% by weight. iv) an acid, latent acid or metal salt catalyst is applied to the textile material. The impregnated textile material is then dried and heated to cure the resin forming composition. The component (i) can be prepared by absorbing formaldehyde in an aqueous solution of urea or by dissolving urea in an aqueous solution of formaldehyde and concentrating by removing water. Although the order and manner in which the above components are mixed is not important it is preferred to dissolve the urea and catalyst in the water and add the resulting solution to component (i). Catalysts that may be employed include weak acids, latent acids, for example ammonium chloride, ammonium dihydrogen phosphate ammonium sulphate and ammonium thiocyanate which develop acidity in the mixture on heating, or metal salts for example zinc nitrate, zinc fluoroborate, zinc chloride and magnesium chloride. Particularly useful are mixtures of ammonium salts and buffer salts, for example sodium acetate, disodium hydrogen orthophosphate and sodium dihydrogen orthophosphate. Examples describe the application to yarns, threads, woven, non-woven and knitted fabrics made wholly or partly from natural or regenerated cellulose or synthetic polymers of polyamides. |
