| 摘要 |
PURPOSE:To obtain a molded product having a uniformly foamed core part, in producing a composite molded product consisting of a surface layer part composed of a resin layer containing a fibrous reinforcing material and a core part composed of a foamed core, by previously expanding foamable resin particles using an induction heating system. CONSTITUTION:A surface layer part forming material consisting of a fibrous reinforcing material 20 and a separation layer 21 is arranged along the inner wall surface of a mold whose cavity can be heated by high frequency voltage and a resin mixture 24 containing foamable resin particles 22 high in polarity and a liquid molding resin 23 is provided to a part becoming a foamed core. After the mold is closed, the particles 22 and the resin 23 are selectively heated to sufficiently high temp. by applying high frequency voltage to the mold cavity and it is prevented that heat is diffused to the inner wall surface of the mold by the heat insulating effect of the surface layer part forming material to uniformly heat a core part and, at first, the particles 22 are uniformly heated to be foamed. Subsequently, the liquid molding resin 23 is cured and the molded product in the mold is cooled to be taken out of the mold. |
