| 摘要 |
Disclosed is a process for the production of a hollow article comprised of a biaxially oriented thermoplastic resinous material, comprising the steps of heating a sheet of thermoplastic material to a temperature above the orientation temperature of the thermoplastic material; clamping an area of the heated thermoplastic sheet between a first mold half and a second mold half, the first mold half containing a pre - form mold surface having a configuration predetermined to provide for uniform wall thickness of the hollow article to be formed, the surface being at a temperature which is not higher than the orientation temperature of the thermoplastic material, and the second mold half having a cavity which corresponds to the shape of the hollow article to be produced; forcing the heated thermoplastic sheet by pressure differential into the first mold half against the surface; maintaining the thermoplastic sheet in contact with the surface for a period of time sufficient to bring the thermoplastic sheet to its orientation temperature; and forcing the thermoplastic sheet into the second mold half by means of a pressure differential which is sufficient to cause the thermoplastic sheet to conform with the cavity in the second mold half to form a hollow article with a force sufficient to substantially, molecularly orient the thermoplastic material in both the longitudinal and lateral directions.
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