Patent GB-545770-A (GB)
Title: Process for stabilizing the dimensions of textile fabrics
IPC: D06C7/02
Filed: 1940-12-13
Abstract: 545,770. Treating textiles with liquids &c. ; finishing fabrics : artificial silk &c. SYLVANIA INDUSTRIAL CORPORATION. Dec. 13, 1940. No. 17646. Convention date, Dec. 13, 1939. [Classes 2 (ii) and 15 (ii)] [Also in Group VIII]  The dimensions of fabrics containing potentially adhesive fibres are stabilized by shrinking them while the potentially tacky fibres are in the tacky condition, and fixing the shrunk fabrics byrendering the tacky material non-tacky, adhesion between the fibres in the fabric is thus secured. The fabrics may be made from singles yarn containing a mixture of potentially tacky and non-tacky fibres or from doubled yarns containing the two kinds of fibres. The shrinkage of the fabrics may be partial or complete and may be effected on woven, knitted, netted. or other fabrics in one or more directions. As non-adhesive component there may be used fibres of cotton, flax, jute, wool, hair, silk, asbestos, glass, mineral wool, regenerated cellulose, cellulose hydrate, cellulose esters, cellulose ethers, natural or synthetic resins. The potentially adhesive fibres may be of a thermoplastic synthetic resin, e.g. polycoumarone, poly indene, poly vinyl compounds, polystyrene, poly sterol aldehyde, poly furfural ketone, a urea-, thiourea-, or phenol-aldehyde resin, an amine-aldehyde, sulphonamide-aldehyde resin, an alkyd resin, drying oil-modified alkyd resin, polyacrylic resin, sulphur-olefine resin, a polyamide resin, artificial rubber such as poly-butadiene, an olefine-polysulphide, an isobutylene polymer, chloroprene polymer, polyvinyl halide, or a copolymer, or a mixture of resins. The resins may be those which are hardened by heat or those which are not so hardened. The potentially adhesive fibres may be of cellulose esters or ethers, including ether xanthates and thiourethanes, or they may be obtained from solutions containing mixtures of cellulose derivatives and resins, or they may be of natural or synthetic rubber. The fibres may be subjected to stretching prior to formation of the fabrics. The shrinking treatment may then be effected in presence of a shrinking agent or while heating. Shrinking may be effected by mechanical means. The fabrics may be stretched in one direction while permitting shrinkage in another direction. They may be moistened and stretched in the direction of one-of the constituent sets of yarns, wbile the thermoplastic fibres are in tacky condition, warp or weft, and while leaving the other set free from tension, and then dried while maintaining the tension on the one set of yarns. Knitted fabrics may be treated in this way. The moist fabric may be stretched in one direction and allowed to shrink and crinkle in the other direction. It is dried under tension, moistened while free of tension so as to allow the first stretched yarns to crinkle, and then dried under pressure but free of tension. The adhesive fibres are rendered tacky during the final drying step. The fabric may be moistened, mechanically compressed in one direction so as to crinkle the yarns, and dried while the pressure is maintained. Activation of the adhesive fibres may take place before, during or after the drying step, and de-activation may take place after the drying by cooling, while the fabric is maintained in the shrunk condition. The fabric. may be moistened while one set of yarns is under tension and the other set is allowed to contract. The yarns previously under tension may then be mechanically compressed. A swelling agent may be used instead of water for the shrinking treatment. The fabric may be subjected to squeezing by pressure rollers while the fibres are in adhesive condition. The thermoplastic fibres may be rendered tacky by hot air, hot water, or contact with hot surfaces, with or without the aid of solvents, plasticizers, or pressure. De-activation may be effected. by cooling, in the case of thermoplastic resins or cellulose derivatives, or by heating to a higher temperature in the case of heat-hardening resins. In an example, a fabric made of yarns containing viscose staple fibres and staple fibres of a vinyl acetate-chloride copolymer is passed over heated rolls to activate the fibres and is then mechanically shrunk in length and width while the polymer is in a plastic state. The fabric is then cooled. In another example, a fabric containing fibres of ethyl cellulose and of cotton is treated with a solvent for the ethyl cellulose, shrunk, heated to evaporate the organic solvent and pressed, and then cooled. The crinkle imparted to the fabric is rendered permanent. The set shrunk condition is stable to laundering, dry cleaning, and wearing. Specifications 359,759, 370,814, and 372,803, [all in Group VIII], are referred to.