Abstract: A closure for a container with a neck portion and an external helical thread formed on the neck portion includes an upper wall and a skirt formed integrally with and extending generally downwardly from the upper wall. An internal helical thread is formed on the skirt for engaging the external helical thread of the neck portion to thereby secure the closure to the container. The internal helical thread is preferably asymmetrical in cross section. A first annular seal extends generally radially inwardly toward a central axis of the closure from the inner skirt surface. The first annular seal sealingly engages the outer surface of the neck portion. A second annular seal extends generally axially downwardly from the upper wall and sealingly engage an inner surface of the neck portion. A thickness of the neck portion between the first and second annular seals is greater than the distance between the first and second annular seals before installation of the closure on the container.

Abstract: A closure for connection to a container with a threaded neck portion includes an upper wall with a lower surface and a skirt formed integrally with and extending generally downwardly from the upper wall. An internal helical thread is formed on an inner surface of the skirt for engaging the threaded neck portion to thereby secure the closure to the container. An inner annular seal extends generally axially downwardly from the upper wall to sealingly engage an inner surface of the neck portion. The inner annular seal has an inner seal apex area and a downwardly sloped surface extending generally downwardly and away from the upper wall to the inner seal apex area. A gas barrier seal has an annular sealing bead positioned between the inner seal apex area and the upper wall inner surface for sealingly engaging the inner surface of the neck portion. The downwardly sloped surface of the inner annular seal holds the annular sealing bead at least adjacent the lower surface of the upper wall.

Abstract: A mold assembly for a container closure includes a mold portion with a stripper ring adapted for engaging a shoulder of the closure, and a threaded core having an external, asymmetrical helical thread defining an internal, asymmetrical helical thread of the closure. The external, asymmetrical helical thread has a ramped surface defining a ramped surface of the internal, asymmetrical helical thread. Relative linear movement between the stripper ring and the threaded core causes withdrawal of the threaded core from the closure in a linear direction. The ramped surfaces of the internal and external, asymmetrical helical threads cooperate to facilitate the withdrawal.

Abstract: A closure for a container with a neck portion and an external helical thread formed on the neck portion includes an upper wall and a skirt formed integrally with and extending generally downwardly from the upper wall. An internal helical thread is formed on the skirt for engaging the external helical thread of the neck portion to thereby secure the closure to the container. The internal helical thread is preferably asymmetrical in cross section. A first annular seal extends generally radially inwardly toward a central axis of the closure from the inner skirt surface. The first annular seal sealingly engages the outer surface of the neck portion. A second annular seal extends generally axially downwardly from the upper wall and sealingly engage an inner surface of the neck portion. A thickness of the neck portion between the first and second annular seals is greater than the distance between the first and second annular seals before installation of the closure on the container.

Abstract: A closure for a container with a neck portion and an external helical thread formed on the neck portion includes an upper wall and a skirt formed integrally with and extending generally downwardly from the upper wall. An internal helical thread is formed on the skirt for engaging the external helical thread of the neck portion to thereby secure the closure to the container. The internal helical thread is preferably asymmetrical in cross section. A first annular seal extends generally radially inwardly toward a central axis of the closure from the inner skirt surface. The first annular seal sealingly engages the outer surface of the neck portion. A second annular seal extends generally axially downwardly from the upper wall and sealingly engage an inner surface of the neck portion. A thickness of the neck portion between the first and second annular seals is greater than the distance between the first and second annular seals before installation of the closure on the container.

Abstract: A mold assembly for a container closure includes a mold portion with a stripper ring adapted for engaging a shoulder of the closure, and a threaded core having an external, asymmetrical helical thread defining an internal, asymmetrical helical thread of the closure. The external, asymmetrical helical thread has a ramped surface defining a ramped surface of the internal, asymmetrical helical thread. Relative linear movement between the stripper ring and the threaded core causes withdrawal of the threaded core from the closure in a linear direction. The ramped surfaces of the internal and external, asymmetrical helical threads cooperate to facilitate the withdrawal.

Abstract: A closure for connection to a container with a threaded neck portion includes an upper wall with a lower surface and a skirt formed integrally with and extending generally downwardly from the upper wall. An internal helical thread is formed on an inner surface of the skirt for engaging the threaded neck portion to thereby secure the closure to the container. An inner annular seal extends generally axially downwardly from the upper wall to sealingly engage an inner surface of the neck portion. The inner annular seal has an inner seal apex area and a downwardly sloped surface extending generally downwardly and away from the upper wall to the inner seal apex area. A gas barrier seal has an annular sealing bead positioned between the inner seal apex area and the upper wall inner surface for sealingly engaging the inner surface of the neck portion. The downwardly sloped surface of the inner annular seal holds the annular sealing bead at least adjacent the lower surface of the upper wall.