Mitsui Chemicals, Inc.

Eiichi Sugihara

Michio Eriguchi

Shigeo Nishikawa

Masaki Misumi

Haruo Inoue

Kaoru Yorita

Yoko Shimada

Masahiro Takedachi

Akira Uchiyama

Yuichi Ito

Takanori Sueda

A process for injection-foaming a thermoplastic resin by using an injection molding machine with a two-stage-compression screw, injecting a physical foaming agent into the cylinder of the machine at a pressure lower than the storage pressure of the physical foaming agent, mixing it with a melted resin and expanding the volume of the cavity of the mold at the time of injection, and an injection molding machine and resin composition suitable therefore.

Molding machine for injection foaming

Process for injection foaming, and machine and composition therefore

This invention provides a method for stably adding a predetermined amount of supercritical carbon dioxide at a fixed delivery rate into a forming machine and also a process for producing an expanded thermoplastic resin product by making use of the addition method. Carbon dioxide is charged from a liquefied carbon dioxide cylinder (,) into a predetermined amount deliverable pump (,) while allowing the carbon dioxide to remain in a liquefied state. When the carbon dioxide is pressurized and delivered by the predetermined amount deliverable pump (,), a delivery pressure of the carbon dioxide is controlled at an optional pressure within a range of from a critical pressure (7.4 MPa) of carbon dioxide to 40 MPa to deliver the carbon dioxide without any fluctuation of the amount of the delivery by setting up the pressure of a pressure control valve (,). The carbon dioxide is heated to a critical temperature (31&deg; C.) of carbon dioxide or higher to convert it into supercritical carbon dioxide. This supercritical carbon dioxide is then added to a molten thermoplastic resin in the forming machine (,).

Addition method of supercritical carbon dioxide, and production process of expanded thermoplastic resin product by making use of the addition method

A process is provided for the production of expanded olefinic thermoplastic elastomer product having good external appearance, flexibility and heat resistance. This process features using, as raw materials, a particular olefinic thermoplastic elastomer and carbon dioxide as a blowing agent.

Process for the production of expanded olefinic thermoplastic elastomer products

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Sodegaura, Japan

Eiichi Sugihara