| 摘要 |
PURPOSE:To enhance eluation workability and molding resin of high injection temperature by performing injection molding with a core having a heat-resistant coating film on the surface set in a cavity. CONSTITUTION:A heat-resistant film is formed by applying uniformly a fluorine or silicone resin heat-resistant coating material (type A) or a type B heat- resistant coating material constituted of a solvent with powder such as silica sand, zircon sand or the like as an aggregate heated in molds 1 and 2 heated up to the normal temperature to approximately 80 deg.C or applying the type B heat-resistant coating material and then carrying out wet-on-wet coating with the type A heat-resistant coating material. After that, a low melting point alloy core 4 which has been low temperature treated (immersed in dry ice or liquid nitrogen atmosphere) down to -20 deg.C--50 deg.C is provided, and then resin such as polysulfone or the like is injected into a cavity 3 to mold a molded product. Then, the molded product is released from the mold, and the core 4 is eluted by immersing the same in boiling water or putting in water in water vapor, and a plastic product of integrated and sophisticated shape is manufactured. |
