GB944569A - Process for the treatment of cellulosic textile materials - Google Patents

Abstract

Cellulosic textile materials are crease proofed and rendered dimensionally stable on wetting by treating them with an aqueous mixture containing formaldehyde, or a substance which forms or liberates formaldehyde, and a pentaerythritol and then heating them in the presence of an acidic substance, the mixture possibly containing an aldehyde other than formaldehyde but any dialdehyde present not constituting more than 25% by weight based on the weight of the formaldehyde. The pentaerythritol may be pentaerythritol, dipentaerythritol or tripentaerythritol and the acidic substance may be a free acid, e.g. oxalic, tartaric or phosphoric acid, preferably with dissociation content between 6 x 10-5 and 6 x 10-2, the aqueous mixture preferably being acidified to a pH of between 1.4 and 2.0, or a substance which liberates acid on heating, e.g. zinc nitrate or magnesium chloride, or an acid salt of a polybasic acid having a dissociation constant in water of not less than 10-6 with a metal of which a less acid salt with the same polybasic acid is precipitated before said acid salt on concentration and/or on heating a solution thereof, e.g. magnesium dihydrogen phosphate. After treatment with the aqueous mixture which may contain a softening agent, e.g. a stearamide derivative of a salt of triethylene tetramine, the textile materials may be dried and heated to a temperature of 110 DEG -170 DEG C. Fibres, yarns or woven, knitted or non-woven fabrics of cotton, viscose rayon or linen alone or in admixture with cellulose acetate, nylon or wool may be treated. Before or after treatment with the aqueous mixture the materials may be treated with caustic alkali of mercerising strength, e.g. 55-63 DEG Tw caustic soda solution for 15-60 minutes at room temperature. If the materials are treated with the caustic alkali after treatment with the aqueous mixture, they may be given a second treatment with the aqueous mixture. The treated materials possess the property of retaining creases and mechanical effects, e.g. pleated, glazed and embossed effects, made before or during treatment. Specifications 437,361, 780,043, 827,645 and U.S.A. Specification 2,785,996 are referred to.