Patent GB-386374-A (GB)
Title: Improvements in or relating to the production of crepe yarns and fabrics
Filed: 1931-06-04
Abstract: 386,374. Crape yarns and fabrics. BRITISH CELANESE, Ltd., 22, Hanover Square, London, DICKIE, W. A., and MONCRIEFF, R. W., of British Celanese, Spondon, near Derby. June 4, 1931, Nos. 27514 (divided on 386,344) and 27515. [Classes 120 (iii) and 142 (iv).] In the production of highly twisted crape threads, the twist is applied in at least two stages with an intermediate treatment with steam or other vapour. The yarn may in addition be subjected to treatment with water vapour before twisting or after the total amount of twist has been applied. Examples of suitable vapours are the vapours of hydrocarbons, e.g. benzene, alcohols, halogenated hydrocarbons, esters such as ethyl acetate, or mixtures of two or more thereof. The crape threads may consist of or contain cellulose acetate filaments, filaments of other organic derivatives of cellulose, regerenated cellulose, natural silk, cotton, or mixtures thereof, and may consist wholly or in part of staple fibre. The first twisting is preferably such as will cause a close packing of the filaments. The subsequent twisting is preferably effected by drawing the yarn axially from a rotating package as described in Specification 304,806, [Class 120 (ii), Spinning, twisting, &c.]. Some or all of the twist may be irregular as described in Specification 358,585. Wetting agents, or hygroscopic or deliquescent substances, may be applied to or incorporated in the yarns or filaments prior to a twisting or steaming operation. The treatment may be effected by winding the yarn on to perforated bobbins and treating with the vapour by means of pressure or suction, or both, or the vaporous treatment may be effected simultaneously with the twisting operation. After the vaporous treatment the yarn may stand, and the further twist may be applied after a partial or complete drying. Drying may conveniently be effected by means of the perforated bobbin apparatus used for treatment with vapour. The crape yarns may be sized at any stage of their manufacture, e.g. with the sizes described in Specifications 348,589 and 357,169, or with the coatings described in Specification 352,451. Such sizes or coatings may be applied intermittently, as described in Specifications 362,523, 365,040, and 365,041. Lubricant such as olive or castor oil, or oleic acid may be applied to the yarn prior to twisting. Fabrics containing the finished yarn may be treated with swelling agents, e.g. as in Specifications 352,000, 356,233, and 357,084. If desired the substance used for the treatment of the yarn may itself be one capable of swelling the filaments in the presence of water, e.g. ethyl alcohol. In an example, cellulose acetate yarn of 100 denier containing 26 filaments is twisted to 26 turns per inch and wound on to metal bobbins. The packages are then steamed for 5 minutes at 2-3 lbs. pressure, and the yarn twisted to 70 turns per inch, e.g. as in Specification 304,806, [Class 120 (ii), Spinning, twisting, &c.]. The prepared yarn is woven into a warp of cellulose acetate yarn of low twist, two picks of left-hand twist alternating with two picks of right-hand twist, the resulting fabric being treated first in water at 30‹ C. for 15 minutes, and then in a 3 gram per litre soap solution for 1¢ hours at 30-80‹ C. The fabric is washed, hydroextracted and dried without tension. Specifications 332,903, [Class 120 (iii), Yarns &c.], 357,576, 357,577, 375,355, and 386,344 also are referred to.