| 摘要 |
A process for the manufacturing of an article made of plastic material, the article comprising an expanded foam filled core with an average density in the range 50-600 kg/m<SUP>3 </SUP>and a solid or semi solid outer skin with an average density above 700 kg/m<SUP>3</SUP>. The process comprises the steps of injecting a predetermined amount of molten thermoplastic material into the cavity of a closed mould, the thermoplastic material containing an expanding agent followed by allowing the thermoplastic material to solidify somewhat closest to the surface of the whereby a skin is formed. A first portion of the mould is then retracted while a second portion of the mould is retained in a closed position, whereby a volumetric increase of the mould cavity is achieved. The pressure in the mould hereby decreased allowing the expanding agent to expand the thermoplastic material. The molten thermoplastic material is then allowed to cool and solidify to a degree where the mould may be opened and the article is removed from the mould.
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