| 摘要 |
<p>A plastified mass of thermoplastic material containing an expanding agent is extruded and sliced into pieces by shaped cutting edges to produce--on expanding--elements which are shaped in a billowed manner or a double-bubble manner. The billowed elements have an inturned peripheral edge which prevents nesting and interlocking together when used in a shipping container. Similarly, the double bubble elements preclude nesting and interlocking.</p> |
