| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method of a hollow molded product made almost constant in its rate of hollow and eliminating the occurrence of defects such as warpage, deformation, expansion, burst and the like. SOLUTION: An injection time is controlled constant to inject a molten resin in a mold cavity while a dwelling time is controlled constant to raise the density of the molten resin and, after a pressurized fluid is injected in the molten resin, the injected pressurized fluid is discharged during the cooling of the molten resin. By this constitution, since a constant amount of the pressurized fluid can be injected in the molten resin even if the pressure of the pressurized fluid is constant, the hollow molded product constant in its rate of hollow can be manufactured. COPYRIGHT: (C)2006,JPO&NCIPI |
