| 摘要 |
The invention relates to an element of a thermoplastic of the polyester or polyamide type, and preferably of polyethylene terephthalate, the element consisting of an edge part which surrounds a body in an arrangement in which the latter is sunk relative to the edge part. The element is formed from a blank of mainly amorphous material or from a material having a crystallinity of less than 10%, the blank being, for example, a flat plate, a blank shell or the like. The body or parts thereof are shaped by stretching the blank until that material which is located within the material sections of the blank flows to from the edge part in the element, the material stretched to flowing in the body assuming a crystallinity of between 10 and 25%, while the crystallinity in the material in the edge part and in the unstretched parts retaining its original value of less than 10%. There is also disclosed a process and equipment for manufacturing the element. |
