| 摘要 |
Multilayer structure comprising, in sequence, metal or metallized substrate layer (5), layer of polypropylene-based binder (6) extruded at speed higher than 100 m/minute and optional polypropylene layer (2), is new. The binder layer (6) is rendered non-separable from metal/metallized layer (5) by thermal treatment, but it can be peeled off polypropylene layer (2). Multilayer structure comprising, in sequence, metal or metallized substrate layer (5), layer of polypropylene-based binder (6) extruded at speed higher than 100 m/minute and optional polypropylene layer (2), is new. The binder layer (6) is rendered non-separable from metal/metallized layer (5) by thermal treatment, but it can be peeled off polypropylene layer (2). Thermal treatment rendering layers (5) and (6) non-separable can be conducted using infra-red irradiation, or by passing through a hot air tunnel, or by induction method, to bring metal layer (5) to temperature higher than that of melting point of binder layer (6). The layer of binder (6) is sandwiched between metal layer (5) and polypropylene layer (2) whose melting point is higher than that of binder, and the structure can be peeled off using force of separation between layers (6) and (2) equal 8-15 N/15 mm. Independent claims are also included for (1) a lid (4) (of bowl or box -shaped container), comprising structure as claimed, where the metal of metallic or metallized substrate layer is aluminum; (2) container made of polypropylene or polypropylene-coated material and closed with lid (4) as claimed; and (3) container made of structure as claimed (both containers sterilizable and resistant to food acids, fats and technical solvents.
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