Patent GB-1226053-A (GB)
IPC: C08J9/36
Filed: 1968-04-02
Abstract: 1,226,053. Laminates. DUNLOP CO. Ltd. 2 April, 1969 [2 April, 1968], No. 15712/68. Heading B5N. A laminated sheet material is produced by assembling a sheet of non-cellular plastics material with a sheet of non-compressed cellular plastics material and compressing the assembly at a temperature above the softening point of the non-cellular plastics material such that the assembly remains in a compressed state when the pressure is removed. The non- cellular plastics material, e.g. thermoplastic and isocyanate-curable polyurethanes, thermoplastic and curable acrylic resins, nylons, homopolymers and copolymers of vinyl chloride, homopolymers and copolymers of ethylene and propylene, ethylene/vinyl acetate copolymers, butadiene/methyl methacrylate copolymers, ethylene/acrylic acid ionomers and block copolymers of styrene and butadiene may be applied, e.g. by spraying, brushing or extrusion to a releasable support surface, e.g. of stainless steel, glass, poly-(tetrafluoroethylene), polypropylene or paper which may be coated or impregnated with wax, when it is assembled with the non-compressed cellular plastics sheet. The support surface may remain in contact with the non-cellular material during compression of the assembly and when the non- cellular material is subsequently cured or crosslinked the support surface may be removed before or after curing or cross-linking. The non- compressed cellular plastics material which may be a foam of natural or synthetic rubber, polyvinyl chloride, polyethylene, polypropylene, polystyrene or a polyurethane, may be of open-cellular structure and may have distributed in it crimped or non-crimped fibres of polyesters, polyamides, cotton, wool or rayon. The assembly may be compressed between a pair of nip rollers one or both of which may be heated at a pressure of 0À5-100 lb./sq. in. for at least 0À5 seconds at a temperature sufficient to soften the cellular plastics material without destroying the cellular structure. The cellular plastics sheet may be assisted in remaining in the compressed state by means of an adhesive. If the non-cellular material is supported on an embossed flexible support surface a better reproduction of the embossed pattern on the non-cellular surface may be achieved if the laminate is fed out of the nip at an angle of about 45 degrees. The assembly may be bonded to one or more additional sheet materials before, during or after compression. The additional sheet material may be of cellular plastics material which may or may not be compressed and may or may not have the same compression modulus as the other sheet of cellular material or it may be a knitted, woven, non-woven or Arachne fabric comprising rayon, cotton, wool, polypropylene, polyester or polyamide fibres which may be bonded together by an elastomer or resin. The additional sheets may be bonded to the assembly by means of an adhesive, e.g. a rubber latex, by solvent or flame treatment of the surfaces to be adhered or in the case of a fibrous material by needling. The laminated material may be used as a substitute for natural leather in the manufacture of shoe-uppers, shoe-linings, upholstery, clothing and handbags.