| 摘要 |
PURPOSE:To shorten a core removing time and reduce the usage of a soluble material by a method wherein a core used in the production of a synthetic resin tubular object is formed into a shape having the hollow part piercing a molding part up to the baseboard parts provided to both ends thereof using the soluble material and the tubular object is molded from a product resin using this core and the baseboard parts are cut to allow a dissolving solution to flow through the hollow part. CONSTITUTION:For example, a core 5 is formed from a water soluble resin so as to have a hollow shape consisting of a hollow molding part 6 conforming to the through-hole 2 of a tubular molded product and the baseboard parts 7, 8 protruding from both end surfaces of the molding part 6. The hollow part 9 of the molding part 6 pierces the molding part 6 along the center line thereof to extend up to the interiors of the baseboard parts 7, 8. This core 5 can be molded by blow molding or gas injection molding. This core 5 is set to a mold and, after a product resin is injected in the mold, a molded product is taken out to cut the baseboard parts 7, 8. High temp. water is passed through the hollow part 9 to dissolve and remove the core 5. |
