摘要 |
In the course of this method, an amount of expansible mixture is poured into a mould, after which the mould is obturated by means of a plug. A vacuum is created in the chamber of the mould by way of the plug so as to cause the foaming of the mixture. The vacuum is maintained for a period after the foamable mixture has filled the whole of the volume of the mould. At the end of the polymerization of the foamable mixture, the vacuum may be re-applied in the mould, preferably for several cycles, so as to cause the cells of the foam obtained to burst. |