METHOD FOR MANUFACTURING FOAM AND FOAM MANUFACTURING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing a foam by which the foam of a desired size can be stably obtained under simple size control as well as a foam manufacturing device which enables simple size control to be performed and stably manufactures the foam of a desired size. SOLUTION: A pressure at a point of time when a shrinkable molding material not containing a foaming agent is injected into a mold and the internal pressure of the mold begins decreasing is given as P2 and the pressure decrease amount of the internal pressure of the mold from P2 is given asΔP2. On the other hand the minimum pressure between the point of time when the injection of the shrinkable molding material containing the foaming agent into the mold is ended and the point of time when the internal pressure of the mold begins to increase, is given as P3 and the pressure increase amount of the internal pressure of the mold from P3 is,given asΔP3. The sumΔP4 of theΔP2 and theΔP3 is controlled based on the correlation (e.g. Fig. 6) between the size change of the previously obtained foam and theδP4. Thus it is possible to obtain the foam of a desired size by adjusting the size of the obtained foam.