Patent GB-792624-A (GB)
Title: Process for the treatment of textile fibre
IPC: D06M11/17
Filed: 1955-05-19
Abstract: A process for the treatment of textile fibres, including fabrics, for the purpose of improving their mechanical properties, such as resistance to rubbing and splitting, comprises treatment of the fibres with a dispersion containing silica as its main constituent and one or more metal oxides, such as titanium dioxide, zirconium oxide and especially aluminium oxide.  The metal oxide may be present in proportion of 0.5-20 per cent, preferably 1-10 per cent, of the total dispersed oxide present and, in general, from 0.05 to 10 per cent by weight of oxides is applied to the fibres.  The size of the oxide particles present in the dispersion, which is preferably aqueous, is substantially smaller than 0.5m , and preferably smaller than 0.15m .  The dispersion should have a pH above 6, preferably 7-9, and should be free from foreign anions, such as chloride and sulphate; desirably, protective colloids such as starch and cellulose derivatives, wetting agents and mineral oil may be added to the dispersion.  The textile is generally treated by dipping or spraying. It is stated that the use of a dispersion containing increasing amounts of aluminium oxide confers an increasing degree of water-repellency on the material treated.  The dispersions may be obtained by dialysis, peptization or by ionexchange.  Preferably at least one of the oxides is present as an aerogel, and to this end halides of silicon and/or of aluminium, for example, may be thermally decomposed in vaporized form advantageously by hydrolysis; the aerogel is obtained from the oxide aerosol formed, after coagulation has taken place. Alternatively, in the case of a dry-spinning process, the oxides may be employed as gaseous dispersions in powder form.  Again, liquid dispersions in which the oxides have been obtained partly by precipitation from aqueous media and partly from the gaseous phase may be used.  In a modification, the silica dispersion contains a suitable, preferably easily hydrolysable, compound such as aluminium acetate or formate, which hydrolyses to oxide in the course of the impregnation process and subsequent drying treatment.  The process is particularly applicable to polyamides, polyacrylonitrile, cuprammonium fibre, cotton, viscose fabric, and wool.ALSO:Dispersions for use in the treatment of textile fibres contain silica as the main constituent and one or more metal oxides such as titanium dioxide, zirconium oxide and especially aluminium oxide.  The metal oxide may be present in a proportion of 0.5-20 per cent, preferably 1-10 per cent, of the total dispersed oxide present. The size of the oxide particles present in the dispersion, which is preferably aqueous, is substantially smaller than 0.5m , and preferably smaller than 0.15m .  The dispersion should have a pH above 6, preferably 7-9, and should be free from foreign anions, such as chloride and sulphate; desirably, protective colloids such as starch and cellulose derivatives, wetting agents and mineral oil may be added.  The dispersions may be obtained by dialysis, peptization or by ion-exchange. Preferably at least one of the oxides is present as an aerogel, and to this end halides of silicon and/or of aluminium, for example, may be thermally decomposed in vaporized form, advantageously by hydrolysis; the aerogel is obtained from the oxide aerosol formed, after coagulation has taken place. Dispersions in which the oxides have been obtained partly by precipitation from aqueous media and partly from the gaseous phase may also be used.  In a modification, the silica dispersion contains a suitable easily hydrolysable compound, such as aluminium acetate or formate, which hydrolyses to oxide in the course of the impregnation process and subsequent drying treatment.ALSO:To improve their mechanical properties, such as resistance to rubbing and splitting, dry-spun textile fibres are treated with a gaseous dispersion containing silica as its main constituent and one or more metal oxides such as titanium dioxide, zirconium oxide and especially aluminium oxide. The metal oxide may be present in a proportion of 0.5-20 per cent, preferably 1-10 per cent, of the total dispersed oxide present and, in general, from 0.05 to 10 per cent by weight of oxides is applied to the fibres.  The size of the oxide particles present in the dispersion is substantially smaller than 0.5m , and preferably smaller than 0.15m .