Filter stopper made of a cellular material with a binder used for a vessel has a cavity which is open to the lower side and extends upwards in the central region of the stopper in an axial direction.

摘要

Filter stopper is made of a cellular material with a binder and is permeable for gases exiting the vessel. the stopper has a cavity (15) which is open to the lower side and extends upwards in the central region of the stopper in an axial direction. A region of the material of the filter stopper remains above the cavity. Preferred Features: the diameter of the cavity varies with the stopper. The height of the cavity varies in the stopper. A further conic section (13) is connected to an upper conically tapering secti9on (11).