| 摘要 |
PURPOSE:To prevent draw-down and to obtain a hollow resin molding high in rigidity of a projecting part by blow-molding a parison by the use of a forming mold equipped with a slide core having a recessed part or a projected part and thereafter retreating and moving the slide core and filling the dissimilar molding material having the quality of material different from the parison into the formed space. CONSTITUTION:A parison A extruded from an extruder is blow-molded by a forming mold 1 equipped with a first slide core 4 having a recessed part 4a. A projected part b3 correspondent to the recessed part 4a of the first slide core 4 is formed in the main body b1 of a molding. Thereafter the first slide core 4 is retreated and moved by the supply pressure of dissimilar molding material C. This dissimilar molding material C is filled into the space 5 formed by retreating motion of the first slide core 4. In such a way, only a projecting part b2 can be molded of the dissimilar molding material C. Since increase in weight of the parison A can be prevented at a time of extrusion, draw-down phenomena are prevented and also rigidity of only the projecting part b2 can be enhanced. |
