| 摘要 |
976,317. Laminates and laminating. PITTSBURGH PLATE GLASS CO. July 30, 1963 [Aug. 2, 1962; June 13, 1963], No. 30121/63. Heading B5N. A transparent assembly comprises a sheet of flexible plastics material 28 e.g. polyvinyl butyral or a polyester siloxane elastomer, the sheet 28 having a metal insert 29, a sheet 26 having a rubber frame 27 and an electroconductive coating of tin oxide and a sheet 30 having a frame 31 of phenolic resin, the sheets 26, 30 being glass or rigid synthetic plastics material such as polymethyl methacrylate, a diallyl diglycol carbonate polymer, a methyl-a-chloroacrylate polymer, an acrylic resin or a polyester resin. The assembly is laminated by sealing the assembly in a bag having walls 11, 12 and then placing the sealed assembly in an oil autoclave. The walls of the bag are made from a layer 13 (Fig. 4) of oil- and moistureresistant plastics such as polyethylene glycol terephthalate or a polyamide and a layer 14 of heat-sealable plastics material such as polyethylene which has an embossed surface having channels 36. The bag is made with the embossed surface innermost and is sealed along three edges leaving one edge free. The bag containing the assembly is sealed by placing the free edge of the bag between jaws 42, 44 (Fig. 6), closing the jaws and evacuating the bag by a vacuum pump (not shown) connected to pipe 50 and channel 46. The free edge of the bag is then heat sealed by passing an electric current through a heating element 60. The sealed assembly is then placed in an oil autoclave to bond the layers together under heat and pressure, the bag being stripped from the assembly when the bonding has been completed. To prevent the bag bonding to the assembly the assembly may be wrapped in a parting material such as " Cellophane " (Registered Trade Mark), or the edge of the assembly may be wrapped with a polythene backed tape, leaving the main surfaces covered by the bag after bonding to act as protective layer. |
