摘要 |
1286858 Artificial leathers TORAY INDUSTRIES Inc 4 Nov 1969 [5 Nov 1968] 53952/69 Heading D1R A textile sheet article comprises a fibrous mass composed of bundles of fibres in which the fineness and/or the number of the fibres in a bundle varies along the thickness direction of the article. The articles are made by needling superimposed webs formed from different composite fibres comprising fine fibres in a matrix and dissolving out the matrix. The different composite fibres contain different numbers of fine fibres and/or fibres of different thickness, also the thickness of the composite fibres and/or the ratio of fine fibres to matrix may vary. The composite fibres may comprise fibres of polyethylene terephthalate in a matrix of nylon 6 which is removed by formic acid, hydrochloric acid, or a mixture of calcium chloride and methanol, or fibres of nylon 6 or polyethylene terephthalate in a matrix of polystyrene which is removed by trichlorethylene or toluene. The inner fibres may also be formed of polyamide, polyester, polyolefine, polyvinylchloride, polyvinylidene chloride, polyacrylonitrile, polyurethane, or copolymers thereof. The matrix must be capable of being removed without damaging chemically the fine fibres, and comprises high polymers which are different from those of the fine fibres, or similar 'but differing in molecular weight, crystal structure, or resistance to chemical solvents. The consolidated webs may be impregnated with binder, e.g. a polyvinyl alcohol or dimethyl formamide solution containing poly urethane and polyacrylonitrile butadiene copolymer. The finished article may be hot calendered, shrunk, split, buffed, coated with high polymer solutions or emulsions, or coloured, and is useful as an artificial leather or a felted material. |