Chisso Corporation

Other

Honda Giken Kogyo Kabushiki Kaisha

Kouichi Honda

Michio Yoshizaki

Mikihiko Kimura

Tamio Furuya

Youichi Kugimiya

Takakiyo Harada

Yasuhiro Mochizuki

Satoru Iriyama

Yasuki Okanemasa

Provided is a polypropylene resin foam-molded article which has a rib having a relatively small thickness and which has an improved strength at a boundary part between a main body part and the rib part without increasing a thickness of the rib part. The polypropylene resin foam-molded article is obtained by molding a material for a foam-molded article using a polypropylene resin, wherein the molded article comprises a main body part and a rib part provided vertically to the main body part; the rib part has a thickness (T ) of 3 mm or less, or a thickness ratio (T /T ) of a thickness of the rib part (T ) to a thickness of the main body part (T ) is 0.8 or less; the main body part and the rib part each comprise a non-foamed surface layer and an intermediate layer having a foamed structure; and the intermediate layer in the main body part is connected to the intermediate layer in the rib part. It is molded from the material for a foam-molded article using a polypropylene resin in which a melt flow rate and a melt tension satisfy a fixed relation.

Polypropylene resin foam-molded article

The present invention provides a thermoplastic resin structure which has a three-layer structure of flexible skin layer/flexible foamed material layer/hard substrate layer wherein each of the layers comprises a thermoplastic resin capable of melt-adhesion with each other, and the flexible foamed material layer is formed by the injection foam molding method. The resin structure exhibits the capability of being easily recycled and, at the same time, can be produced at a low cost, which has not been achieved by a conventional structure using a cross-linked foamed sheet or a urethane foam, while maintaining the performance in appearance, cushioning, rigidity and the like, and thus markedly useful for application fields requiring high performance in cushioning, sound absorption, heat insulation and the like in automobiles, household electrical appliances, general industrial parts and the like.

Thermoplastic resin structure

An object is to provide a thermoplastic resin molded article concurrently having excellent heat insulating properties, rigidity, and lightness, and to provide a method for producing the same. A molded article made from a thermoplastic molding material comprises: a multilayer structure portion having a surface layer composed of a non-foamed type of said molding material and an internal layer composed of a foamed type of said molding material; and a portion composed of only a non-foamed type of said molding material. The molded article is produced by injecting and filling an expandable thermoplastic molding material which is melted in the heating cylinder that is adjusted to have the temperature of its tip part higher than that of its rear part, into a cavity having a 10 to 95% volume of the volume of the molded article, conducting a first cooling until the molding material becomes the condition that the surface layer contacted with the metal mold is solidified but the internal layer is melted, enlarging the volume of the cavity to the volume of the molded article to foam at least a part of the internal layer, and conducting a second cooling to take out the molded article.

Method for producing molded article

To provide a polypropylene-based resin exterior panel which has the same appearance qualities as a coated product though it is not coated and which is excellent in rigidity and impact resistance, a polypropylene-based resin exterior panel comprising a surface layer made from a highly transparent resin composition comprising a propylene-.alpha.-olefin random copolymer having a melting point lower than 155.degree. C. and a melt flow rate (MFR) of 0.5 to 30 g/10 min and a clarifying nucleating agent, an intermediate layer made from a colored resin composition comprising a propylene-.alpha.-olefin random copolymer having a melting point lower than 155.degree. C. and an MFR of 0.5 to 30 g/10 min and a coloring pigment, and a base layer made from a base composition comprising a propylene-.alpha.-olefin block copolymer having a melting point of 155.degree. C. or higher is produced by forming a skin by laminating the surface layer and the intermediate layer, disposing the skin in an injection mold, and injecting and filling the base composition to form the base layer.

Polypropylene-based resin exterior panel and process for producing the

Molded article and method for producing the same

Growing community of inventors

Ichihara, Japan

Kouichi Honda