Patent ID: 6245263
Filing Date: 2001-06-12
Classification: B29C

Abstract:
A process of injection molding a foamable plastic composition which comprises the steps of:a) filling completely a molten foamable plastic composition into a cavity, and reducing the volume of the cavity in the middle of injection or immediately after injection, so that the volume of the cavity at the time of initiating the injection (Volume A) is equivalent to 1.1-5 times as large as the volume of the cavity at the time reduction is completed (Volume B);b) cooling the composition to the state wherein a solidified layer in contact with a mold surface mingles with a molten inside layer;c) enlarging the volume of the cavity to that of the desired molded article; andd) after further cooling, removing the molded article wherein the produced molded article has all of its surfaces made from the injected foamable plastic composition.