| 摘要 |
PROBLEM TO BE SOLVED: To readily obtain high interfacial bonding strength, high rigidity, good slidability, chemical resistance, fatigue resistance or the like by avoiding a skin layer on a surface of a primary molding in the contact surface of the primary and secondary moldings. SOLUTION: A crystalline resin material A is pre-molded to form a primary molding, to which a thermoplastic resin material B is secondarily injection- molded and fused therewith, so as to integrate both of them. The joining surface of the primary-side resin material is subjected to a flame treatment or a hot air treatment, and a portion or all of the surface layer of the joining surface is melt-treated, e.g. by being re-melted, gradually cooled and solidified, thereby substantially avoiding the skin layer of the surface. The flame treatment or hot air treatment is readily applied to only the joining surface of the primary molding, e.g. by applying the hot air at a high temperature to a cavity after the primary molding is provided in the secondary mold which is then closed. The molding method is most preferably an injection molding. |
