| 摘要 |
PROBLEM TO BE SOLVED: To provide a method which can reduce an amount of steam used in in-mold foam molding compared with conventional techniques, and enables inexpensive production of thermoplastic resin foamed moldings having quality comparable with that attained by conventional techniques.SOLUTION: A mold has a cavity 9 of a desired shape formed by combining a first mold 2 and a second mold 3, both allowing steam to pass therethrough, in such a way as to form the cavity 9. In the molds 2, 3, steam supply conduits through which steam is supplied to the molds 2, 3, when steam valves 12, 17 are opened and drain conduits discharging fluid from the molds 2, 3 when drain valves 13 and 18 are opened, respectively. After filling the cavity 9 with preliminarily foamed particles of a thermoplastic resin, a mold heating step, a one side heating process, an opposite side heating process, a double-side heating process and a heat retaining process are carried out to obtain a foamed resin molding, wherein the opposite side heating process is carried out with both the drain valves 13, 18 of the first and second molds in a closed state. |
