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:
Aug. 31, 2004
Filed:
Jan. 16, 2003
Yasuhiro Saito, Osaka, JP;
Kazuishi Mitani, Osaka, JP;
Tatsuro Umeyama, Osaka, JP;
Koji Okuhata, Osaka, JP;
Toshiaki Hashimoto, Osaka, JP;
Hoya Corporation, Tokyo, JP;
Abstract
A method for manufacturing a disk-like glass substrate that is used as an information recording medium. The glass substrate is acid resistant. When an index of acid resistance is the maximum depth at which components other than silica dissolve from the glass substrate during immersion of the glass substrate in 1 percentage of weight of sulfuric acid, the acid resistance of the glass substrate is represented by the maximum depth of 0.5 nm to 10 nm. A linear texture is formed by pressing a tape against the glass substrate in a circumferential direction of the glass substrate while feeding abrasion slurry to the surface of the glass substrate. Acid treatment is performed on the glass substrate on which the texture is formed.