| 摘要 |
1327978 Dishes MOBIL OIL CORP 14 Dec 1971 [5 Jan 1971] 58011/71 Heading A4A [Also in Division B5] A laminated plastics dish 10 comprising an oriented thermoplastic film 14, e.g. bi-axially oriented polystyrene, and a thermoplastic foam 12, e.g. polystyrene, has an upwardly extending annular side portion with a peripheral rim 16 which tapers to an edge, the foam at the rim edge being compressed at least 50 per cent based on the thickness of the remaining foam. The densities of the foam in the base and uncompressed side portion and in the rim may be 3-6 and up to 10-50 lb/ft<SP>3</SP> respectively. A second thermoplastic film 18 may be present. The initial laminate may be prepared by heat-sealing a foam, which retains its heat following extrusion, to a pre-heated film by means of a heated roller. The laminate is then thermoformed between male and female mould members; the edge may be trimmed by a heated knife. Alternatively the rim may be thermoformed following a main thermoforming operation to produce the dish. The foam may be pigmented and the film may be translucent or transparent. The dish may have a design imprinted thereon. |
