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:
Jun. 27, 1995
Filed:
Jan. 14, 1993
Jun Shimizu, Miyagi, JP;
Junichiro Kudo, Miyagi, JP;
Sony Corporation, , JP;
Abstract
A metal mold device for molding a disc substrate formed by molding a synthetic resin material and having a raised portion on the inner surface of the disc substrate, includes a fixed metal mold and a movable metal mold for defining together a mold cavity for molding the disc substrate. A mold releasing resistance in the form of suitably sized projections or recesses, is provided at a portion of the fixed metal mold or the movable metal mold mating with the outer rim of the disc substrate being molded or at the outer peripheral surface of the raised portion to permit an as-molded disc substrate to be released easily and reliably from a stamper bearing a pattern of pits and lands or pre-grooves and to prevent molding distortions from being produced in the disc substrate being molded.