GB592660A - Improvements in or relating to methods of producing textile fabrics having a shaped patterned structure - Google Patents

Abstract

A textile fabric is locally rendered resistant to shrinkage by imprinting it with a substance or substances which undergo a chemical change within the fibres whilst the fabric is in a stretched condition, whereby the substances are permanently fixed within the fibres, and the fabric is then subjected to a wet, mechanical or other shrinking treatment which does not involve chemical action on the fibres, the portions of the fabric which are not fixed being thereby contracted. Patterned effects are thus obtained. Alternatively, the fabric may be formed by interweaving fibres which have been chemically fixed and fibres which are shrinkable. The shrinking treatment may be a treatment with water or steam whilst the fabric is free from tension. The treatment may result in a craped or similar patterned effect. Contrasting coloured effects may be obtained by incorporating selected dyestuffs in the printing liquid, or by interweaving preliminarily dyed or printed non-shrinking yarns. Contrasting colour effects may also be obtained by dyeing the fabric with dyes for which the parts which have been rendered shrink-proof by chemical treatment have an affinity which differs from that of the untreated parts. The shrinking treatment may be applied to fabrics containing highly twisted crape yarns. The fabrics may contain fibres of natural or regenerated cellulose, superficially etherified or esterified cellulose, wool, silk, casein, or polyamides. The local fixing against shrinkage may be effected by treating the fabric with partially condensed artificial resins or the components thereof and then subjecting them to a hardening treatment. The fabric may be treated with an oil-modified artificial resin which is then dried and hardened on the fabric. The fabric may be treated with an aldehyde or an aldehyde-producing substance, or it may be subjected to local esterification or etherification. Reagents may be used which render the treated portions water-repellent. Mechanical shrinking apparatus may be used for the shrinking treatment. In wet shrinking treatments, soap solutions or dilute solutions of acids, alkalis or salts may be used provided that they exert no chemical action on the material of the fibre. In an example, viscose fabric is printed with an oil-modified alkyd resin with ammonium sulphate as catalyst, and a siccative, dissolved in organic solvents. The fabric is dried and then heated to harden the resin. The goods are then craped by application of moisture, e.g. immersion in hot water, weak alkaline craping baths, soap solutions or water containing a wetting agent. Cotton fabric may be similarly treated. The treated material may be treated with dyestuffs to obtain differential colour effects. In another example, regenerated cellulose yarn which has been rendered shrink-proof by treatment with dimethylol urea is interwoven with untreated regenerated cellulose staple fibre yarn. The fabric is then subjected to scouring to remove sizing and is thereby craped. Instead of dimethylol urea there may be used a sulfine resin with formaldehyde and "Velan P.F." (Registered Trade Mark). In another example, viscose fabric is printed with a printing colour containing formaldehyde, "Velan P.F." and ammonium sulphate, tartaric acid, boracic acid, or sodium phosphate. The fabric is dried and baked. It is then freed from sizing, bleached and craped. A shaped pattern is obtained. The Specification as open to inspection under Sect. 91 describes also other methods of locally rendering the fabric resistant to shrinking. The fabric may be treated with viscose, cuprammonium cellulose, cellulose ether, or other cellulosic solutions and then with agents which precipitate the cellulose, or it may be treated with agents such as cuprammonium, zinc chloride, carbon bisulphide in alkali, organic bases, or thiocyanates, which have a superficial solvent action on the fibres. This subject-matter does not appear in the Specification as accepted. Reference has been directed by the Comptroller to Specifications 433,902, 452,150, 543,613 and 547,846.