摘要 |
<p>The side wall of a container is joined to the bottom portion thereof by a first frustoconical portion and a first semi-torroidal portion which, in turn, is joined to a second semi-torroidal portion: and, a bottom closing portion. In one embodiment the second semi-torroidal portion is joined to the bottom closing portion by a second frustoconical portion, a third semi-torroidal portion, and, a third frustoconical portion. In another embodiment the bottom closing portion is substantially flat but adapted to be domed outwardly under pressure and "cricket" inwardly when pressure is relieved.</p> |