Patent attributes
A dispensing closure for a product container includes a plastic closure body having a top wall with a dispensing opening which is arranged in line with a dispensing passage of the container. The closure includes a self-closing valve embodied as a membrane made of a plastic foil. The membrane has a valve portion, which in use can assume an open position under influence of product pressure, and an attachment portion surrounding the valve portion. The attachment portion of the valve is sealed to an annular support surface integrally formed in the closure body along the periphery of the opening or being formed on a plastic annular insert part that is connected to the closure body along the periphery of the opening. The seal between the attachment portion and the support surface includes an annular groove and an inner annular seal zone adjoining the annular groove on a radial inner side.