Die-expanded molding apparatus and method for synthetic resin, and die-expanded molded foam obtained thereby

Abstract

A die-expanded molding apparatus comprising starting material bead supply for supplying beads on a current of air from a tank through a packer into a cavity formed by a core and cavity molds; a plurality of air expulsion devices having air pressure-adjusting components communicating with the cavity, a dual-system air expulsion device being such that steam chambers on the back side of the core mold and the cavity mold are used as the air pressure-adjusting components, each communicating with the cavity through through-holes formed in the core and cavity molds, respectively; an air expulsion device having one or more air pressure-adjusting components communicating with a clearance between the core and cavity molds; and a control for controlling the air pressure in each of the air pressure-adjusting components to be pressurized less than the pressure in the tank.

1 . A die-expanded molded foam, comprising a density of within ±5% of the mean density in various locations in the molded foam.  
   
   
       2 . A die-expanded molded foam as set forth in  claim 1 , wherein the degree of shape complexity is defined as the numerical value obtained by dividing the surface area of the molded foam by the volume, and the degree of shape complexity is 1.1 or more.  
   
   
       3 . A die-expanded molded foam as set forth in  claim 2 , wherein the wall thickness of the thin-walled portions of the molded foam is 10 mm or 3 mm.  
   
   
       4 . A die-expanded molded foam as set forth in  claim 1 , wherein the wall thickness of the thin-walled portions of the molded foam is 10 mm or 3 mm.  
   
   
       5 . A die-expanded molded foam as set forth in  claim 4 , wherein  3  or less beads are disposed in the thicknesswise direction of the thin-walled portions of the molded foam.  
   
   
       6 . A die-expanded molded foam as set forth in  claim 1 , wherein  3  or less beads are disposed in the thicknesswise direction of the thin-walled portions of the molded foam.  
   
   
       7 . A die-expanded molded foam as set forth in  claim 2 , wherein  3  or less beads are disposed in the thicknesswise direction of the thin-walled portions of the molded foam.  
   
   
       8 . A die-expanded molded foam as set forth in  claim 3 , wherein  3  or less beads are disposed in the thicknesswise direction of the thin-walled portions of the molded foam.