Patent GB-1068781-A (GB)
Title: Method of manufacturing non-woven bonded fibrous fabrics such as artificial leathers
IPC: D04H1/54
Filed: 1964-04-16
Abstract: Composite fibres are spun from a mixture of a polyamide and a polyolefine.  The polyolefine may be a homopolymer of ethylene or propylene or a copolymer with vinyl acetate, vinyl chloride or acrylonitrile.  The polyamide and polyolefine may be prepared separately and then mixed and melted, or one of them may be mixed with the monomeric precursor of the other, and the precursor then polymerized.  In the examples, fibres are spun from mixed melts of: (Example 1) 50 parts of nylon-6 and 50 parts of polypropylene; (Example 2) 50 parts of nylon-11 and 50 parts of polyethylene; (Example 3) 55 parts of nylon-6 and 45 parts of polypropylene; and (Example 6) 50 parts of nylon-6 and 50 parts of polystyrene.ALSO:To make a non-woven bonded fibrous fabric, such as an artificial leather, composite fibres are spun from a mixture of a polyamide and a polyolefine and formed into a web.  This web is then treated with a liquid comprising a solvent or swelling agent for one of the polymers but not a solvent for the other, and then removing at least a part of the solvent or swelling agent either by heating or by treatment with a liquid which is not a solvent for either of the polymers.  The fibres may be in tow or staple form, and may be formed into the web by direct laying from the spinning apparatus or by air-laying or water-laying techniques. The polyolefine may be a homopolymer of ethylene or propylene or a copolymer with vinyl acetate, vinyl chloride or acrylonitrile. The polyamide and polyolefine may be prepared separately and then mixed and melted, or one of them may be mixed with the monomeric precursor of the other, and the precursor then polymerized.  Other fibres which may be included in the web include those of polyvinyl alcohol, polyethylene terephthalate and mixed-spun composite fibres of nylon-6 and polystyrene.  Solvents or swelling agents referred to include alcoholic solutions of a metal salt, methyl sulphone, monohydroxylamine, a halogenated alcohol, benzyl alcohol, tetraline, kerosene, toluene or xylene.  The lap may be compressed before or after treatment with the solvent or swelling agent and the latter may be applied by spraying or by immersion of the web in the liquid.  Improved bonding of the fibres may be achieved by impregnating the porous fabric with a solution, emulsion or powder of polymerisable substances such as prepolymers of formaldehyde with urea or melamine, ethylene oxide or ethyleneimine with silicon tetrachloride, vinyl chloride, acrylonitrile, vinyl acetate, acrylic acid, methacrylic acid or prepolymers thereof and subsequently causing polymerisation in situ.ALSO:To make a non-woven bonded fibrous fabric, such as an artificial leather, composite fibres are spun from a mixture of a polyamide and a polyolefine and formed into a web which is subsequently coated.  This web is then treated with a liquid comprising a solvent or swelling agent for one of the polymers but not a solvent for the other, and then removing at least a part of the solvent or swelling agent either by heating or by treatment with a liquid which is not a solvent for either of the polymers. The fibres may be in tow or staple form, and may be formed into the web by direct laying from the spinning apparatus or by air-laying or water-laying techniques.  The polyolefine may be a homopolymer of ethylene or propylene or a copolymer with vinyl acetate, vinyl chloride or acrylonitrile.  The polyamide and polyolefine may be prepared separately and then mixed and melted, or one of them may be mixed with the monomeric precursor of the other, and the precursor then polymerized.  Other fibres which may be included in the web include those of polyvinyl alcohol, polyethylene terephthalate and mixed-spun composite fibres of nylon-6 and polystyrene.  The lap may be compressed before or after treatment with the solvent or swelling agent and the latter may be applied by spraying or by immersion of the web in the liquid.  The porous fabric is coated with a solution, emulsion or powder of polymerisable substances such as prepolymers of formaldehyde with urea or melamine, ethylene oxide or ethyleneimine with silicon tetrachloride, vinyl chloride, acrylonitrile, vinyl acetate, acrylic acid, methacrylic acid or prepolymers thereof and subsequently causing polymerisation in situ.