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:
May. 23, 1989
Filed:
Aug. 27, 1987
Katsutarou Ichihara, Tokyo, JP;
Nobuaki Yasuda, Zushi, JP;
Yoshiaki Terashima, Yokosuka, JP;
Senji Shimanuki, Atsugi, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
According to a disk-shaped magneto-optical recording medium of the invention, a transparent thin film serving as an interference layer is formed on a transparent substrate. The thin film is subjected to a plasma surface treatment, thereby decreasing the fused oxygen content in at least a surface portion thereof. A recording layer of a rare-earth-transition metal amorphous ferrimagnetic alloy thin film is formed on the plasma surface-treated film. Since the content of active, fused oxygen contained in at least the surface portion of the film decreases, rare-earth element oxide can hardly be formed in a boundary region between the recording layer and the transparent thin film. The content of the rare-earth element in this region is smaller than the average content in the overall recording layer.