PLASTIC CLOSURE WITH ANTI-BACKOFF TEETH ON ITS THREADS

摘要

A closure (10) for a container having carbonated or otherwise pressurized contents includes a top wall portion, and an annular depending skirt portion (16). An internal thread formation (18) mates with a like thread formation (T) of an associated container (C). To facilitate gas venting during closure removal, the container (C) includes a plurality of axially extending vent grooves (G). Release of gas pressure during closure removal is facilitated by providing the closure (10) with at least one, and preferably a plurality of rotation-inhibiting projections (40) positioned adjacent to the internal thread formation (18). The projections (40) interferingly engage with the vent grooves (G) of the associated container (C), thus providing increasing frictional drag during closure removal to permit dissipation of gas pressure from within the container.