| 摘要 |
PURPOSE:To decrease an amt. of adhesion of a residue caused by decomposition of a blowing agent by heating the neighborhood of the end part of a cavity of a mold by means of a heater heating locally the part. from the time just before a resin is filled in this end part to several sec or min after the filling is finished and cooling thereafter. CONSTITUTION:When a foamable resin compsn. with an amt. which is smaller than the vol. of a mold cavity 1 is injected in the mold cavity 1 while the compsn. is melted, the compsn. fills in the mold cavity 1 and reaches the end part of the mold cavity while it is expanded. When electric current is energized in a heater 5 before the resin compsn. reaches the end part, the end part of the cavity 1 is heated and the temp. is elevated and a gas contg. a decomposed residue of a blowing agent generated from the resin compsn. is not cooled and therefore, the wall of the mold cavity 1 is not adhered with the residue and it is evacuated from a vent channel 4. When the resin is filled in the mold cavity 1, heating is stopped and the temp. of the mold is lowered by passing cold water through a cooling channel 3. When the resin is solidified, cooling is stopped and a product is taken out. |
