| 摘要 |
PURPOSE:To obtain a molding having a smooth and flat surface by a short shot by a method wherein a saturated vapor and a heating gas for drying are orderly induced into a mold cavity and after the wall surface is heated and dried, a pressure gas is filled therein and next thereto, a foamy resin is extruded. CONSTITUTION:First of all, a saturated vapor 6 is filled in a mold cavity 1 and a wall face thereof is heated. Next, a gas exhaust valve 5 is opened and along with this, a heating gas for drying 10 is made to flow in the mold cavity 1 to exhaust a condensed moisture. Next thereto, the gas exhaust valve is closed and a breaking valve 8 is opened to make a pressure gas 14 flow and a given pressure is obtained. And directly thereafter, a foamy synthetic resin is extruded from an extrusion cylinder nozzle 4 and it is induced into the mold cavity 1 while the pressure gas is being exhausted. And then, breaking valves 8, 11 are closed as well as a gas exhaust valve 5 is opened and resin is made to foam to perform an extrusion. EFFECT:A molding having a less residual molded distortion is obtained and there is no improper sinkage. |
