Molding method of polyolefin resin

Abstract

Abstract PURPOSE:To manufacture a flat platelike molded article without having a twist, a warp and a sink, by performing injection compression molding by making a compression ratio into a figure more than 1+1/t and less than 1+7/t [(t) is a thickness of the molded article]. CONSTITUTION:Polyolefin resin is injected within a cavity 3 to be constituted with a stationary side mold 1 and a movable side mold 2 and high pressure clamping is performed at a compression ratio of more than 1+1/t and less than 1+7/t [(t) is a thickness of a molded article]. When the compression ratio is more than 1+7/t, a compression molded portion through clamping becomes surplus, a cooling effect through the mold is remarkable, internal strain is increased, and a warp and a twist are apt to occur and when the compression ratio is less than 1+1/t, an injection molded portion becomes excessive and sufficient effect is not obtained.

Inventors

• 👤 Hidenori Kurokawa
• 👤 黒川　英紀
• 👤 Masabumi Shimokawa
• 👤 下川　正文

Bibliographic Details