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. 04, 1994
Filed:
May. 16, 1990
Applicant:
Inventors:
Yoshimitsu Kobayashi, Tokyo, JP;
Yoshiyuki Kisaka, Kurashiki, JP;
Takashi Hashimoto, Sagamihara, JP;
Toshifumi Kawano, Yokohama, JP;
Mitsugu Wakabayashi, Kurashiki, JP;
Assignee:
Mitsubishi Kasei Corporation, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G11B / ; G11B / ;
U.S. Cl.
CPC ...
3692753 ; 369288 ; 430945 ;
Abstract
Disclosed herein is a read-only optical disk comprising an annulus transparent substrate of a synthetic resin having information pits thereon, a reflective layer comprising an Al alloy containing Ta and a protective layer provided thereover. The read-only optical disk according to the present invention is excellent in the corrosion resistance and has a high reliability.