Toyoda Gosei Co., Ltd.

Yoshihiro Inada

Hiroshi Mukai

Yasunobu Teramoto

Takahiko Sato

Hirohisa Narukawa

Hiroshisa Narukawa

A sandwich molded article comprising a thick skin or outer layer, a thin skin or outer layer, and a core layer surrounded by these skins or outer layers. A process for producing said sandwich molded article by the use of a mold(s) which comprises adjusting the temperature of an inner surface of the mold corresponding to a skin portion of the molding desired to be made thick, to a temperature lower than that of an inner surface of the mold corresponding to a skin portion of the molding desired to be made thin; injecting a skin material in a softened state into the mold; and then injecting a core layer material in a softened state into the skin material. According to the present invention, there can be obtained a sandwich molded article having a core layer from which the distances to the obverse and the reverse of the molded article are different. This molded article can be given a satisfactory decorative surface and has deformation-preventing ability.

Process for producing a sandwich molded article

A orifice passage for introducing excessive resin into a disposal tab forming cavity is provided at one end of a main cavity in a mold for sandwich molding. The section of the orifice passage is thinner in the central portion than in the opposite sides thereof. A thermoplastic elastomer for forming an outer layer of the molding is injected into the main cavity and then talc-containing polypropylene for forming the core of the molding is injected. The flow rate of the resins flowing through the orifice passage at this time becomes substantially uniform over the entirety of the section. Therefore, the talc-containing polypropylene sufficiently extends toward the opposite sides of the main cavity.

Method of producing molding

A mold for making a double layer molded product, such as a molded product of sandwich construction or a hollow molded product having a dam within the mold cavity adjacent its gate. The dam projects in a direction transverse to that in which the inner-forming material is injected, and a gap is defined between the dam and the walls of the cavity. With this configuration, the core thickness of the molded product of sandwich construction, or the skin thickness of the hollow molded product, are made uniform.

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Inazawa, Japan

Yoshihiro Inada