| 摘要 |
PURPOSE:To obtain economically the blow molded product with protrusions which does not generate a material loss and does not have a pinch-off scar, by expanding the required part of a parison in a mold and trimming said expanded part by the mold and shaping the protrusions at the sides of the parison, then blow molding it. CONSTITUTION:The parison 29 composed of a thermoplastic resin is extrusion molded in the blow mold 21 in which split molds 22 and slide molds 23 are opened. Next, the split molds 22 are closed, an air is blown and a part of the parison 29b is expanded between the slide molds 23, then by closing the slide molds 23 the part of the parison 29b is pressed flatly and the protrusions 12 are shaped. Further again, an air blow is done and the parison 29 is blow molded into a hollow object 11, etc., thereby obtaining the purpose blow molded product with protrusions. |
