GB355256A - Improved process for rendering textiles water repellant - Google Patents

Abstract

The water-repelling properties of scoured cotton, washed wool, artificial silk, and other textile fibres are improved by subjection to treatment with esterifying agents under such mild conditions that there are introduced the radicles of higher fatty acids in amount not exceeding twice the content of such radicles in the natural fibres. By this means there is reintroduced into the fibres radicles that were removed during the cleaning process or during the process of manufacture; and the radicles so introduced need not necessarily correspond with those previously extracted or removed, thus the radicle of lauric acid may be introduced into cotton. The esterifying agent which may be a fatty acid chloride or anhydride may be dissolved in an organic liquid provided the latter does not dissolve or swell the fibre, in particular the cellulose or cellulose esters or ethers of which artificial silk fibres may be composed; or it may be employed in the form of an emulsion in water, dilute alcohol, &c. Further, in the esterification the use of powerful auxiliary esterifying means such as alkali is to be avoided, the esterification being assisted by the addition of a weak organic base. In examples, threads or fabric are treated at 60-80 DEG C. with a 5 per cent solution of stearyl chloride in benzene, to which diethylaniline has been added; or the textile material may be boiled in a 2 per cent solution of palmityl anhydride in benzene; and the esterification may be assisted by the addition of a small quantity of pyridine; cotton wool is impregnated with an emulsion prepared by melting a mixture of palmitic and stearic anhydrides with vegetable gum, adding ammonia solution, and diluting with water. Specification 313,616, [Class 2 (ii), Cellulose &c.], is referred to. The Specification as open to inspection under Sect. 91 (3) (a) refers to the fundamentally different dyeing properties of the treated materials, and to the use of divalent acids such as adipic acid as the esterifying means. This subject-matter does not appear in the Specification as accepted.