| 摘要 |
PROBLEM TO BE SOLVED: To provide a thermoplastic resin foam which shows the uniform expansion state of a thermoplastic resin and has microexpanded cells with a high expansion ratio, a method for manufacturing the thermoplastic resin foam by injection-molding/a device using this method and a method/a device for manufacturing the thermoplastic resin foam with the capability of stably mass-producing the foam having a high expansion ratio. SOLUTION: This method for manufacturing the thermoplastic resin foam uses an injection/compression-molding process for increasing the volume of a cavity when a molten resin is packed into the cavity and a counter-pressure process using a gas of specified pressure previously packed into the cavity. In addition, the method comprises a step to pack the molten resin impregnated with a pneumatogen under a supercritical state into the cavity; a step to detect the pressure of an airtight space formed outside of the cavity by communicating with the cavity; and a step to control the pressure of the cavity based on the results of the detection by the step to detect the pressure of the airtight space. COPYRIGHT: (C)2004,JPO |
