GB561402A - Improvements in imparting shrinkage qualities to textile materials of regenerated cellulose - Google Patents

Abstract

Textile materials consisting of regenerated cellulose yarns in associated or unassociated form, produced by saponifying stretched artificial yarns having a basis of an organic acid ester of cellulose, are impregnated with a solution containing between 30 and 75 per cent by weight of a mercerising agent which is a base, this solution having a shrinking action on the yarns; the base is neutralised immediately after impregnation by treating the yarns with an acid, and the acid is then washed out of the yarns. The treated yarns or fabrics undergo considerable shrinking when they are dried from the wet state. The wet fabrics may thus be fixed over a framework of an aeroplane wing, fuselage, tail, or other part, or of a lamp-shade or screen, and when dried they become taught owing to the shrinkage which takes place. The treatment with the base improves the extensibility of the yarns, and the immediate neutralisation of the base by acid gives products of improved tenacity. The cellulose ester yarns may have been stretched in presence of dioxane or other organic swelling agent or in presence of steam or hot water. The mercerising agent used for treating the regenerated cellulose yarns may be sodium hydroxide, or potassium hydroxide in aqueous or alcoholic solution. Dilute mineral acid such as hydrochloric or sulphuric acid or an organic acid such as acetic acid may be used for neutralising the base. After washing, the materials may be dried in a hot drying chamber. The dried fabrics may be coated with cellulose ester or other dopes. Specification 501,768 is referred to.