| 摘要 |
PROBLEM TO BE SOLVED: To provide a hot runner die for optical disk double picking molding by which two sheets of substrates for optical disks having different sheet thicknesses can be simultaneously molded by one molding machine in such a manner that right and left separate heating heaters are provided for a manifold and a runner gate, the temperature controls are independently performed, and also, as the temperature regulating control, individual settings for a temperature for a temperature raising, a starting time for the temperature raising, a completion time for the temperature raising, a temperature raising speed, and a heat insulating temperature are made possible to freely regulate the flowing-in amounts of right and left resins. SOLUTION: The heating heater for the manifold is provided on the hot runner at 6A and 6B. As a molding material, a thermoplastic resin (e.g., a polycarbonate m.p:230°C) is used, and a manifold temperature setting is set at 350 to 395°C. A temperature difference between 6A and 6B is set to be 10 to 30°C, and variations are applied to the jetting pressures of two runner gates 5A and 5B without changing the jetting pressure of a plunger nozzle (a jetting pressure of 100 to 200 kgf/cm2) by generating a viscosity difference of the resins in the manifold. Thus, changing the resin amounts flowing into two cavities l8A and l8B without changing runner gate timings is possible. Therefore, the substrates for optical disks having different sheet thicknesses can be simultaneously molded by the same molding machine. COPYRIGHT: (C)2004,JPO |
