Closure cap with injection molded annular gasket and method of making same

摘要

A closure cap and method of making the same wherein an annular or ring-shaped gasket is injection molded onto the inner surface of a cap shell formed of plastic or metal. The annular or ring-shaped gasket includes radially extending tabs integrally formed therewith, one of said tabs being formed at a location wherein the plastic melt is fed to an annular gasket-forming channel in a mold core and another of said tabs being formed at the location wherein plastic melt is discharged from said channel. Preferably, said other tab includes a cold well formation which communicates with the annular gasket through a connecting portion of reduced cross-sectional area with respect to the cross-sectional areas of both the gasket and the cold well formation.