| 摘要 |
<p>An injection-molded piston (23) for an aerosol container (10) has a face portion for contacting and exerting pressure on material to be dispensed, and a thin, flexible skirt (25) depending axially from and circumscribing the face portion for forming an effective seal against the inside wall (12) of the container (10). The outer wall of the skirt is continuous, while the circumference of the inner wall has alternating areas of constant thickness along said areas and areas of minimum thickness, the curved portions forming with the outer wall a plurality of sections, the thickness and circumferential extent of each of which decrease axially along the skirt (26a) toward its distal end. The piston (23) includes a depending extension (26) on the skirt which aids sealing.</p> |
