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:
Jan. 17, 1989
Filed:
Oct. 13, 1987
Applicant:
Inventors:
Assignee:
Sony Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B32B / ; C08G / ;
U.S. Cl.
CPC ...
428412 ; 428332 ; 428216 ; 428693 ; 428900 ; 428463 ; 427322 ; 427444 ; 523205 ; 523332 ; 2641761 ;
Abstract
An optical information record medium is disclosed in which an optical information record layer is formed on a substrate made of a polycarbonate resin. The polycarbonate resin is purified to remove the residual chlorine in the resin enough to form the substrate containing no more than 1.0 ppm of chlorine ion. By reducing the residual chlorine ion in the polycarbonate substrate, anticorrosion characteristics of the optical information record medium are greatly improved.