Process and apparatus for producing synthetic bottle closures

摘要

A process for producing synthetic bottle closures composed of a cylindrical core element made from a foamed polymer material and of an outer layer composed of a compact and unfoamed polymer material, connected to said core element and enveloping it, the polymer melts being prepared in a first and a second extruder and joined in a manifold die such that an enveloped melt strand emerges which is taken off and then, after curing is cut and chamfered. The polymer melt for the core material is mixed at least once between the first extruder and the manifold die and is subsequently cooled.