| 摘要 |
The surface quality of rigid foam plastics articles, e.g. of polystyrene, is improved by heating the boundary surfaces during the foaming operation to a higher temp. than would be necessary for the foaming. This leads to a commencement of sintering in the outer layer of material. Surfaces produced as above have, in the surface zone, fine granulate pref. of a higher density. This method enables objects to be produced having surfaces which are considerably more resistant, accompanied by a reduction in the raw material required. |
