| 摘要 |
PROBLEM TO BE SOLVED: To provide an injection foam molding method of a thermoplastic resin capable of obtaining a foamed injection-molded product having a desired foam size and density and good in surface state simply, safely and efficiently and reducing the load applied to the environment, and an injection foam molding apparatus. SOLUTION: A foamable gas is used as a foaming agent to be supplied to an injection device 30 under a pressure of 0.1-below 1.0 MPa and a pressure adjusting gas is preliminarily injected in a mold cavity 10a in a mold clamping state to make the pressure in the mold cavity 10a almost the same as the supply pressure of the foamable gas. Thereafter, a foaming agent-containing thermoplastic resin is injected and charged in the mold cavity 10a from the injection device 30 and, during or after the injection and charging of the foaming agent-containing thermoplastic resin into the mold cavity 10a, the pressure adjusting gas injected in the mold cavity 10a is discharged. After the foaming agent-containing thermoplastic resin is injected and charged in the mold cavity 10a, the mold cavity 10a is expanded to foam the foaming agent-containing thermoplastic resin. COPYRIGHT: (C)2007,JPO&INPIT |
