| 摘要 |
A process for the production of a molded article having a hollow structure, using an injection molding machine equipped with a mold apparatus having a mold provided with a cavity, said process comprising the steps of (a) positioning a plug in its forward end position in the cavity with a plug-moving means before a molten resin is injected, (b) moving the plug toward its backward end position nearly in parallel with a flow-axis direction of the molten resin, with the plug-moving means or under a pressure of the injected molten resin, after the injection of the molten resin is initiated, (c) introducing a pressurized fluid into the molten resin in the cavity through a pressurized fluid introducing portion while the plug is moving, and (d) moving the plug up to its backward end position nearly in parallel with the flow-axis direction of the molten resin with the plug-moving means or under the pressure of the molten resin and/or the pressurized fluid introduced into the molten resin, and then, cooling and solidifying the molten resin in the cavity to form a hollow structure in the resin.
|
