| 摘要 |
PURPOSE:To contrive improvement in the yield of production by a method wherein resin having the oxidation speed lower than that which will be used later is used at the start of each resin injecting process. CONSTITUTION: A monomer is injected by pressing down a piston 9. The monomer 7, which is loaded first and having a long gelation period, reaches and stays at the gate part of the cavity 4 located close to a pot 1, but it does not become hard easily because of its long gelation period. Subsequently, a monomer 8 having a short gelation period is filled in a runner 2, and it is pressure-filled into each cavity 4 at a high pressure. At this time, the monomer which previously arrived at the gate part of the cavity 4 located close to the pot 1 remains there, but as the oxidation period of this monomer is long, it does not interrupt the flow-in of the new monomer and the increase in pressure of the cavity 4, thereby enabling to pressure-fill the monomer into all cavities 4 uniformly at high pressure. As a result, no gate stop phenomenon is generated, and the yield of production can be improved remarkably. |
