| 摘要 |
<p>An in-mold expansion molding product (11) of polypropylene resin having a skin (8) is produced by clamping a mold A (13) lined with a skinning material (8) and a mold B (14) together to form a mold cavity (7), filling the cavity (7) with pre-expanded polypropylene resin particles, feeding steam into the cavity through a steam hole (4) of the mold B (14) to preheat the pre-expanded particles at a temperature lower than a temperature at which the particles fuse with one another, steaming the pre-expanded particles thus treated, and finally heating the steamed pre-expanded particles from the side of the mold B (14) above a temperature at which the particles fuse with one another. The final heating may be effected, if necessary, from the side of the mold A (13).</p> |
