| 摘要 |
PURPOSE:To make sure the exhaustion of gas in a cavity and manufacture RIM products without voids by inserting porous bodies that have pores communicating with outer air to suitable spots on the face of a metallic mold. CONSTITUTION:Metallic molds 2 and 3 for RIM (reaction injection molding) have at their portions where gas is liable to be trapped (for example, concave portions such as boss, rib, etc.) porous bodies 19 inserted to communicate the cavity 6 with outer air. Because gas left in the cavity 6 is completely expelled through the porous bodies 19, the products in the molds are free of voids. The porous body 19 here is made by pressing and forming metallic grains Al, Zn, etc.) of 5-50mum in diameter with a binder for them. |
