| 摘要 |
PROBLEM TO BE SOLVED: To injection-mold PP to form a container which is transparent enough for a content to be visually recognized from the outside of the container and has inner cross sectional area increasing from an opening portion to a bottom portion by decreasing core volume when a mold is opened. SOLUTION: A core 10 for molding the inner circumference of a container is composed of 5 separated partial cores 11 to 15. When the partial core 15 is moved to the opening side in the axial direction of the container, the slider 16 slides within a groove 17 to make the partial cores 11 and 12 move in the direction of approaching each other. Thereafter while the partial cores 11 and 12 are moved to the opening side in the axial direction of the container, the partial cores 13 and 14 moves in the direction of approaching each other. This makes the outer diameter of the partial core 15 smaller than the inner diameter of the opening of the container, whereby even if the inner diameter of the container decreases in the direction from the bottom to the opening, the core can be relatively pulled out from the inner side of the injection-molded container via the opening. |
