Coextruded multilayer foamed film for plastic container closures and process for manufacture
First Claim
1. A plastic container closure comprising a threaded or snap-on bottle cap and a liner of a 3-10 mil thick coextruded multilayer foamed film having at least one solid polyolefin film layer and at least one foamed polyolefin layer having an average cell size of less than 0.6 millimeters in length.
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Accused Products
Abstract
A plastic container closure, such as a bottle cap liner or tamper evident seal, is formed from a coextruded multilayer foamed film. The coextruded multilayer foamed film has at least one solid film layer of a first polyolefin blend containing linear low density polyethylene, low density polyethylene, and, optionally high density polyethylene, and at least one foamed layer of a second polyolefin blend containing linear low density polyethylene, low density polyethylene, and optionally ethylene vinyl acetate. The multilayer foamed film may be coextruded using a blown film or cast film extrusion process under defined conditions. the coextruded multilayer foamed film may be laminated to other materials such as polyester film, thermoplastic adhesive films or metallic films and used as a plastic container closure, or may be applied as a liner to a plastic bottle cap.
88 Citations
17 Claims
- 1. A plastic container closure comprising a threaded or snap-on bottle cap and a liner of a 3-10 mil thick coextruded multilayer foamed film having at least one solid polyolefin film layer and at least one foamed polyolefin layer having an average cell size of less than 0.6 millimeters in length.
- 6. A plastic container closure comprising a laminate of a 3-10 mil thick coextruded multilayer foamed film having at least one solid polyolefin film layer and at least one foamed polyolefin layer having an average cell size of less than 0.6 millimeters in length, the multilayer foamed film having a first and second surface and an adhesive joining said first surface of said multilayer foamed film to a polyester film and a metallic foil.
- 8. A 3-10 mil thick coextruded multilayer foamed film suitable for use for a plastic container closure, said multilayer foamed film having at least one solid polyolefin film layer and at least one foamed polyolefin layer having an average cell size of less than 0.6 millimeters in length.
Specification