Plastic closure with compression molded barrier liner
AssigneeOwens-Illinois Closure Inc.
InventorsMark R. Hock, David B. Riffer
Life of this patent
Estimating the term…
Abstract
A plastic closure that includes a cap having a base with a peripheral skirt defining a cap interior and threads on the skirt for securing the closure to a container. A liner is secured to the interior of the cap, preferably by compression molding in situ. The liner preferably consists essentially of a blend of matrix polymer material, particulate barrier polymer material and compatibilizer material. The heat and pressure of compression forms the particles of barrier polymer material into platelets that are oriented essentially parallel to the plane of the closure base.
Claims44
A method of making a plastic closure that comprises the steps of:
- (a) providing a plastic cap that includes a base and a peripheral skirt defining a cap interior,
- (b) placing within said cap interior, on said base, a mold charge that includes a blend of matrix polymer material and barrier polymer material, and
- (c) compression molding said mold charge in situ within said cap interior against said base to form a liner having said barrier polymer material in the form of discrete overlapping platelets within said matrix polymer material and the platelets are oriented essentially parallel to said base.
A method of making a plastic closure that comprises the steps of:
- (a) extruding plastic mold charge material that consists essentially of a blend of matrix polymer material, barrier polymer material and compatibilizer resin material to promote adhesion between said matrix and barrier polymer materials by reactive bonds or non-reactive adhesion mechanisms,
- (b) severing a mold charge pellet from the mold charge material extruded in said step (a),
- (c) providing a plastic cap that includes a base and a peripheral skirt defining a cap interior,
- (d) placing said mold charge pellet within said cap interior, and
- (e) compression molding said mold charge pellet against said base to form a liner on said base having said barrier polymer material dispersed as overlapping platelets within said matrix polymer material and the platelets are oriented essentially parallel to said base.
A method of making a liner for a plastic closure that comprises the steps of:
- (a) forming a pellet that consists essentially of a blend of matrix polymer material, barrier polymer material and compatibilizer resin material to promote adhesion between the matrix polymer material and the barrier polymer material, and
- (b) compression molding said pellet to form a liner disk within which heat and pressure from compression molding form said barrier polymer material into discrete overlapping platelets that are oriented essentially parallel to the plane of the disk.
Dependencies are inferred from the claim text.