Acrylic resin disc for optical use

Abstract

Abstract PURPOSE:To produce an acrylic resin disc which has lower optical anisotropy at high productivity in producing the acrylic resin disc used for an optical system video disc, or the like, by forming specific acrylic resin into the disc of specific size through injection molding. CONSTITUTION:A disc, which is produced from acrylic resin of 20g/10min MFR through injection molding and is of the size of 0.8-1.2mm. thickness and >=150mm. diameter and, further, is having <=X10<-5> index of birefrigence at the part of 50cm apart from the center, is used. Thus, the disc of lower optical anisotropy, which is usable for a record holding body of information for an optical system video disc, is produced by the casting method through the injection molding, which does not need the polymerization and the cutting of the disc and the other, at high productivity.

Inventors

• 👤 Junji Seki
• 👤 Kohei Ozawa
• 👤 Katsuaki Maeda

Bibliographic Details