The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 09, 1990
Filed:
Jul. 31, 1989
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
An improved injection molding process for producing a substrate of an optical disc having a high quality is disclosed. The process includes the steps of: fixing a stamper having protrusions corresponding to pits for recorded information or a groove for tracking onto one mold unit of a pair of mold units of an injection molding machine; combining the mold units to form a closed cavity between the pair of mold units; charging a molten molding resin into the cavity; cooling the resin in the cavity to form a molded substrate; separating one mold unit from another mold unit; and releasing the molded substrate simultaneously from both mold units when the two mold units are separated from each other by applying pressurized air onto both sides of the substrate.