SEALING INSERT FOR A PLASTIC CLOSURE, PLASTIC CLOSURE INCORPORATING SUCH INSERT, METHOD OF MAKING SUCH INSERT AND METHOD OF MAKING A PLASTIC CLOSURE

摘要

A plastic closure that comprises a cap (22) having a base (30) with a peripheral skirt (32) defining the cap interior and threads (34) on the skirt for securing the closure to a container. A liner (20a, 20b or 20c) is secured to the interior of the cap, preferably by being compression molded in situ on the base. The liner consists essentially of a multiplicity of alternating layers of a matrix polymer material such as EVA and a barrier material such as EVOH to resist transmission of gas, water vapor and/or flavorants through the liner. The matrix polymer material preferably is preblended with a compatibilizer material such as a maleic anhydride grafted polymer that ties the matrix polymer material to the barrier material. IMAGE