| 摘要 |
<p>1514553 Non-woven leather substitute ASAHI KASEI KOGYO KK 10 Sept 1975 [13 Sept 1974 8 Aug 1975] 37263/75 Heading D1R A non-woven fabric comprises filaments or fibres having a denier of 0.005 to 0.5 present both as individual filaments or fibres and as bundles thereof, the filaments or fibres within the bundles being autogeneously adhered together, the individual filaments or fibres and the bundles being entangled together yet free to move somewhat at their cross-over points. The fabric may be impregnated with polyurethane and coated with polyurethane to form an artificial leather. Viscose rayon or cuprammonium rayon filaments may be extruded, incompletely coagulated, formed into bundles of 50 to 1000 filaments and allowed to adhere to the other filaments of their bundle. In Examples 9 and 27 a blend of nylon 6 and polystyrene was extruded, solidified and the polystyrene dissolved in hot trichloroethylene or chloraform to leave the nylon 6 "island" filaments which were then caused to adhere to each other by exposure to steam at 130 to 200‹C. Filaments of cellulose diacetate, cellulose triacetate, nylon 66, polyethylene, polypropylene and polyacrylonitrile are mentioned. The filament bundles and/or the fabric formed therefrom may be sized with polyvinyl alcohol, methylmethoxy nylon 6 and/or a nylon 6-nylon 66-nylon 612 copolymer. The size may be removed before or after impregnation of the fabric with a dimethylformamide solution of polyurethane and immersion in water to coagulate the polyurethane. The filament bundles may be crimped in a stuffer box. The filament bundles may be random laid (examples 3, 7, 9, 10, 11, 14, 15, 16, 19) or parallel laid (examples 12, 13, 22) on a wire mesh belt and the resulting fabric may be cross laid. In examples 24-27 a filament bundle is cross wound, e.g. upon a frame of diameter 1m using a traverse guide at a cross angle of 85‹. The layer is then cut along the longitudinal axis of the frame. In examples 17 and 17 the fabric is formed from an aqueous slurry, of cut bundles by a paper-making process. In examples 18, 20 and 21 cut bundles are air laid. In examples 1, 2, 4, 5, 6, and 8 they are carded and cross-lapped. The fabrics may be needled or subject to water jets or to both in either order in order to break some of the bonds between fibres in a bundle and to cause entanglement. In example 3, the fabric is calendered by a pair of rollers at 170‹C before impregnation with polyurethane solution. The amount of individual filaments or fibres and of bundles of 5 or less filaments or fibres is preferably 5 to 95% by wt. of the fibres/filaments. The flexural rigidity in mg/100 denier of the fibrous bundle is determined by a press bending test to be between 0.15 and 5 times the Youngs Modulus (in g/denier) of a filament, Youngs Modulus for a cuprammonium filament being about 100g/denier. The weight, thickness, tensile strength, breaking elongation and ratio of weight of polyurethane to weight of fibres is specified for each example.</p> |
