| 摘要 |
A method of manufacturing hollow articles of thermoplastic materials. Initially, a compact blank, such as a tablet, a palette, a disk or the like, is formed by injection molding into a mold cavity. The blank may be composed of a plurality of layers which surround each other. Subsequently, the blank is compression-molded in the heated state to reduce its thickness and increase its surface area size. Finally, again in the heated state, the compressed blank is formed into a hollow article by a stretching and blow-molding operation. During each injection-molding step, the volume of the mold cavity is adjusted from a minimum volume to a maximum volume at a rate which corresponds to the rate of injection of the respective plastics material. While still in the heated state, at least portions of the injection molded blank are conditioned by additional heat treatments and, subsequently and/or simultaneously, a compressed and condensed mold is formed by a compression molding operation and, finally, a hollow article is formed by a stretching and blow-molding operation.
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