Dispensing closure seals

A dispensing closure having a cap and a spout, said spout having a base shaped as a surface of revolution extending around an axis and a passage leading therethrough from said base, said cap having an external surface adjacent to said end of said base and an opening leading therethrough intercepting said external surface, said external surface being convex and having a uniform cross-sectional configuration adjacent to said opening, said cap and said spout having cooperating means holding said cap and said spout so that said spout may be rotated between an open position in which said passage and said opening are aligned and a closed position in which said end overlies said opening, said cap including a sealing means formed by said external surface around said opening, said sealing means engaging said end of said spout so as to form a seal therewith at all times, in which the improvement comprises:

• said sealing means comprising an edge on said external surface, the base of said spout only touching said edge to form a seal,
• said external surface adjacent to said edge having a cross-sectional configuration such that in all positions of said end said edge engages said end in the same manner so as to form a seal with respect to said end.