| 摘要 |
PROBLEM TO BE SOLVED: To largely restrain generation of irregular releasing such as pit deviation and double transfer at the time of formation of a base plate so as to obtain a bake plate for optical disk having no molding defect by lowering a sucking pressure for sucking and holding a stamper during induction of a resin and heightening it during opening of a mold. SOLUTION: After a mold is closed, a melting resin is induced in a mold cavity 10'. At this time, a sucking force for sucking a stamper 2 is preferably extremely low. A sucking force is 40 KP or lower per unit area (1m<2> ), and a sucking force of 30 KP or lower is preferable. When the force for sucking and fixing the stamper 2 is too weak at the time of mold opening, the stamper 2 is peeled from the mold together with a resin base plate so as to be in a floating state, resulting in pit deviation. At the time of mold opening, the stamper is to be sucked strongly. In this case, fixing with a sucking force of 50KP or higher per unit area is preferable. It is 400mmHg or above in degree of vacuum. |
