| 摘要 |
<p>765,153. Finishing fabrics; seaming; felt. DU PONT DE NEMOURS & CO., E. I. March 10, 1955 [March 10, 1954; May 4, 1954], No. 7072/55. Classes 42 (1) and 42 (2). Textile sheet material is punched with unbarbed needles each of which has in its profile a notch or protuberance such that a line tangential to it and parallel to the longitudinal axis of the needle will not change in direction by more than 90 degrees when moved in either direction around the notch or protuberance in such a way as to remain always tangential thereto. The process is used on non-woven batts or on woven or knitted fabrics in the production of felted or fulled effects. The material may be wholly or mainly composed of non-feltable fibres, whether natural or synthetic. In the case of a batt, the latter preferably contains a proportion of retractable or shrinkable fibres which can be shrunk before or after needling, e.g. by means of heat or a swelling agent, so as to produce a feltlike product. In the case of woven or knitted fabrics, preferably at least 1000 penetrations per square inch are applied until migration of fibres into adjacent or crossing yarns is obtained. The fabric may contain natural, regenerated or sythetic fibres or blends thereof. Fabrics may be teasled or brushed before or after needling. Where the fibres permit shrinking, the fabric may be shrunk before or after needling. Needles according to the invention may be made from standard barbed needles, the barbs being removed by etching in acid and/or by abrasive action so as to give a notch as shown in Fig. 2a. Preferably the angleα, subtended by lines drawn from the upper and lower edges of the notch to the deepest point therein, is at least 90 degrees. Other shapes of notch or protuberance on the needle are disclosed, of which two are shown in Figs. 5 and 16. The crosssectional shape of the needle blade may be triangular, round, flat, elliptical, rectangular or hexagonal. The needle may be made of metal or plastic. In one example, a woven fabric having nylon weft and polyethylene terephthalate warp is teasled on one side, and is then needled from the teasled side so that irregularities of weave are removed and a fulled effect is produced. The process of the invention may be applied to a narrow edging of a fabric to prevent unravelling, or may be used to create fabric designs. It may also be applied to joined or interwoven ends of fabrics, e.g. to produce an endless belt. Specification 712,950, [Group IV (a)], is referred to.</p> |
