Closure cap with improved top-load leakage resistance

摘要

A closure cap of the press-on type wherein the sealant or gasket is flowable both to interlock the closure cap with threads on the container and to form a seal with the end surface of the container. The configuration of a radially inner part of an annular portion of the sealant has been changed to increase the thickness thereof whereby, when the closure cap is applied, a normal seal is formed with the container end sealing surface and a further seal of the piston-cylinder type is formed between the sealant and the radially inner cylindrical surface of the container. This secondary seal permits an overloading of the closure cap relative to the container due to stacking, but maintains the seal between the closure cap and the container even though the sealant may temporarily move away from the end sealing surface of the container.