Method for producing optical disk base

摘要

A method for producing an optical disk base to store, record, and retrieve sounds, images, and information. An improved method for producing an optical disk base includes the steps of injecting a photo-curable resin into a cavity, curing the photo-curable resin by irradiation with light, and demolding, where the photo-curable resin is injected from an injection nozzle having an outside diameter which is substantially equal to the diameter of the center hole of the optical disk base and also having a horn-shaped opening at the forward end. The injection nozzle is arranged at the center of the optical disk base. The forward end of the nozzle is closed after injection and the photo-curable resin is irradiated with light, with the injection nozzle projected into the cavity. A liquid resin is injected in the form of uniform flow without entrapped bubbles, so that the anamolous molecular orientation is avoided and the contamination with insufficiently cured or uncured resin is also avoided.