| 摘要 |
PURPOSE:To provide a technique for obtaining foam of homogeneous biodegradable resin and molding it in a suitable shape. CONSTITUTION:Moisture and biodegradable resin are substantially cast in a cylinder 1, raised at its temperature to the vicinity of a softening point or melting point to be fluidized while the resin is pressurized, and extruded in permeable molds A in which at least part is open-cell porous. Thus, since the resin is abruptly released from a heated and pressurized state, foaming occurs. In this case, when a nozzle 12 is relatively retracted from the molds A, the resin is sequentially clogged from an innermost side of the molds A, and hence it is not forcibly extruded, foamed cells are not collapsed, and a homogeneous foam as shaped in the molds is obtained. |
