Piston for pressurized container and pressurized container with such a piston

摘要

A piston for use in a pressurised dispensing container for dispensing product, which is loaded into the container under pressure and is substantially more flowable when loaded into the container than when dispensed, comprises an annular sidewall (12) having an upper edge (32), a lower edge (34) and an intermediate or centre zone (36). The upper edge (32) is substantially rigid. The lower edge (34) has a diameter that is between 0.254 mm and 0.381 mm greater than the outer diameter of the upper edge (32). The centre zone (36) constitutes a major portion of the piston sidewall (30) between the upper and lower edges and has a diameter that is at least 0.254 mm less than the diameter of the upper edge (32), thereby providing a recessed zone between the upper and lower edges. <IMAGE>