Patent GB-1084505-A (GB)
Title: Synthetic leathers
IPC: D04H1/54
Filed: 1964-09-22
Abstract: Synthetic leather is produced having the structure of an entangled mass of fibres of a natural or synthetic polymer A, which fibres are stuck together by portions of polymeric material B grafted on to A, the polymers A and B being swelled to different extends by at least one solvent.  The material is produced by grafting B on to fibres of A, treating the grafted fibres with a solvent which swells B more than it does A, and drying the treated fibres whereby the softened B sticks the fibres of A together at their points of contact.  Grafting is carried out by dipping fibres of A in a solution of the monomer of B and polymerizing the monomer, e.g. by the action of ionizing radiation or U.V. light. Polymers A specified are polyethylene terephthalate, polyurethane, cellulose, polyvinyl alcohol, polyvinyl chloride, polystyrene, polyethylene, polypropylene and polyamides Monomers specified for making graft component B are butadiene, styrene, acrylonitrile, vinyl acetate, methyl acrylate and methacrylate, and vinyl chloride, and mixtures thereof.  An example describes dipping polyethylene terephthalate fibres in a mixture of methyl acrylate and butadiene containing formic acid, irradiating the fibres with gamma-rays, forming them into a three dimensional structure by needle punching and treating the structure with a saline solution in acetone whereby the grafted material is softened and the fibres are adhered to each other.ALSO:Synthetic leather is produced having the structure of an entangled mass of fibres of a natural or synthetic polymer A, which fibres are stuck together by portions of a polymeric material B grafted on to A.  The material is produced by grafting B on to fibres of A, treating the grafted fibres with a solvent which swells B more than it does A and drying the treated fibres whereby the softened B sticks the fibres of A together at their points of contact.  Polymers A specified are polyethylene terphthalate, polyurethane, cellulose, polyvinyl alcohol, polyvinyl chloride, polystyrene, polyethylene, polypropylene and polyamides. Monomers specified for making graft component B are butadiene, styrene, acrylonitrile, methyl acrylate and methacrylate, vinyl acetate, vinyl chloride, and mixtures thereof. An example describes grafting polyethylene terephthalate fibres with a mixture of butadiene and methyl acrylate, forming them into a three-dimensional structure by needle punching, treating the structure with a solvent which softens the grafted on material thereby causing the fibres to adhere to each other, coating the resulting material with a pigment-containing emulsion of an acrylate copolymer, and hot pressing the material.ALSO:A leather-like material is made by grafting polyethylene terephthalate fibres with a mixture of butadiene and methyl acrylate, forming them into a three-dimensional structure by needle punching, treating the structure with a solvent which softens the grafted on material thereby causing the fibres to adhere to each other, and coating the resulting material with a pigment-containing emulsion of an acrylate copolymer, and then hot-pressing the material.