![]() The particular construction of the end member is not critical to the present invention, and various other constructions can be used. ![]() The metal foil layer in such a composite end member is substantially thinner than a conventional metal end member, e.g., about 0.00015 to 0.003 inch for aluminum and about 0.0005 to 0.0025 inch for steel. 5,069,335, incorporated herein by reference. An alternative end member material is composite material comprising a relatively thin metal foil of aluminum or steel laminated with one or more polymer layers, such as disclosed in U.S. Metal end members on food containers typically are coated with a suitable coating (not shown) to prevent direct contact between the metal and the container contents. For example, the end member can be formed of a suitable metal such as aluminum or tin-plate steel of relatively large thickness, e.g., about 0.005 to about 0.025 inch. The end member 20 can be formed of various materials, as long as it is plastically deformable so as to accommodate the double-seaming operation. ![]() For instance, the closure can comprise a metal foil layer (which provides both structural properties as well as barrier performance), in which case the underside of the foil typically will have a coating of a suitable materia. Where barrier performance against oxygen and/or moisture or other substances is needed, the closure also includes at least one barrier layer (which can also be a structural layer, or can be separate from the structural layer). The closure includes at least one structural layer of suitable material having adequate strength properties to support the forces expected to be exerted on the closure during packaging, subsequent processing (e.g., retort), and shipping and handling. The membrane closure can be formed of various materials or combinations of different materials. 2) and is positioned to be grasped and pulled to open the container. The closure preferably includes a tab portion 33 that remains unattached to the end member after heat-sealing (see FIG. ![]() The container 10 also includes a flexible membrane closure 30 that is attached to the end member 20 by heat-sealing, in such a manner that the closure is readily peelable from the end member to open the container.
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