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:
Nov. 21, 1995
Filed:
Mar. 23, 1992
Applicant:
Inventors:
Assignee:
Sony Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
430273 ; 430945 ; 269287 ; 269284 ;
Abstract
A tape-shaped optical recording medium, in which a recording layer capable of optically recording or reproducing information signals is formed on a flexible base, is disclosed. A protective film formed of a soluble high polymer having a contact angle with respect to water of not less than 100.degree. C. and a glass transition temperature of not lower than 100.degree. C. is formed on the recording layer. The soluble high polymer may be a fluorine-based polymer, such as a tetrafluoroethylene-dioxole copolymer. The protective film has a film thickness in a range of from 0.25 .lambda./n to 0.5 .lambda./n, where .lambda. is a wavelength of a playback light and n is a refractive index of the protective film.