GB795821A - Improvements in the finishing of cellulose ester textile fabrics - Google Patents

Abstract

A woven fabric comprised wholly or in major part of fibres of a cellulose ester of a fatty acid containing up to four carbon atoms, the ester containing at least 2.71 acidyl radicals per anhydroglucose unit, is finished by subjecting it to the action of a liquid softening agent for the cellulose ester under conditions permitting the fabric to shrink until it has shrunk warp-ways at least 5 per cent, as measured after removal of softening agent and drying. Subsequently the degree of crystallinity of the cellulose ester may be increased by a heat treatment, e.g. in air, inert gas, a steam and air mixture, or saturated steam as described in Specification 758,442, [Group IV (a)]. Examples are given of the treatment of cellulose triacetate fabrics, the softening agents used being aqueous acetic acid and aqueous acetone. Other softening agents which may be employed in admixture with water are formic acid, ethyl lactate, glycol mono-acetate, diethylene glycol mono- or diacetate, mono- or di-acetin and water-miscible glycol ethers or esters thereof, e.g. glycol monomethyl ether, glycol monoethyl ether or glycol monomethyl ether acetate. Non-aqueous softening agents may also be employed, e.g. methylene chloride in a diluent such as carbon tetrachloride, benzene, toluene or petrol. The cellulose triacetate fibres of the fabrics may be prepared by wet, dry or melt-spinning processes such as those described in Specifications 687,414, 719,853, 719,860, 721,674, 726,900, 731,930 or 748,772, [all in Group IV (a)], or by the further acetylation of more lowly acetylated fibres, as described in Specifications 448,816, 448,817 and 448,917, [all in Group IV].ALSO:A woven fabric comprised wholly or in major part of fibres of a cellulose ester of a fatty acid containing up to four carbon atoms, the ester containing at least 2.71 acidyl radicals per anhydroglucose unit, is finished by subjecting it to the action of a liquid softening agent for the cellulose ester under conditions permitting the fabric to shrink until it has shrunk warp-ways at least 5 per cent, as measured after removal of the softening agent and drying. Subsequently the degree of crystallinity of the cellulose ester may be increased by a heat treatment, e.g. in air, inert gas, a steam and air mixture, or saturated steam, as described in Specification 758,442. Examples are given of the treatment of cellulose triacetate fabrics, the softening agents used being aqueous acetic acid and aqueous acetone. Other softening agents which may be employed in admixture with water are formic acid, ethyl lactate, glycol mono-acetate, diethylene glycol mono- or diacetate, mono- or di-acetic and water-miscible glycol ethers or esters thereof, e.g. glycol monomethyl ether, glycol mono ethyl ether or glycol monomethyl ether acetate. Non-aqueous softening agents may also be employed, e.g. methylene chloride in a diluent such as carbon tetrachloride, benzene, toluene or petrol. The cellulose triacetate fibres of the fabrics may be prepared by wet, dry or melt-spinning processes, such as those described in Specifications 687,414, 719,853, 719,860, 721,674, 726,900, 731,930 or 748,772, or by the further acetylation of more lowly acetylated fibres, as described in Specifications 448,816, 448,817 and 448,917, [all in Group IV].