| 摘要 |
1323343 Producing cured mouldings CIBAGEIGY AG 11 June 1970 [19 June 1969] 28404/70 Heading B5A [Also in Division H2] A thick-walled, cured, plastics moulding, e.g. an electrical insulator is produced by casting a liquid resin, e.g. an epoxy resin, which is settable in 3-60 mins., without application of pressure in a filled mould heated sufficiently to initiate curing of the resin, the composition temperature being at least 10 % below that of the mould measured in ‹C., the mould and resin temperatures being preferably such that the temperature in the centre of the composition will not reach that of the composition at the mould wall until it is sufficiently set to be removed from the mould; further resin composition is then supplied under low pressure to compensate for shrinkage until the resin has set and the moulding is removed. The mould preferably has a sprue at its bottom for entry of the composition and a vent riser at its top. The temperature of the composition in the sprue is maintained at substantially the original temperature of the composition. |
