Dispensing closure partic. of polyolefin - rotatable spout cylindrical base sealing on cap opening rim in all positions

摘要

A closure includes a spout with a base shaped as a surface of revolution, and a cap having a convex external surface of uniform cross-section adjacent an opening. The spout is rotatable so that its passage can be aligned or non-aligned with the cap opening. The base contacts the opening rim in all positions to form a seal.. The arrangement prevents leakage due to shrinkage.