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. 11, 1999
Filed:
Aug. 29, 1997
Applicant:
Inventor:
Yasunao Kuroda, Osaka, JP;
Assignee:
Onda Techno, , JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C03C / ;
U.S. Cl.
CPC ...
428141 ; 428410 ; 428338 ; 428220 ; 428 641 ; 428 642 ; 428 643 ; 428 644 ; 428 653 ; 4286 / ; 4286 / ; 4286 / ; 501 68 ; 501 69 ; 501 70 ; 369280 ; 360135 ; 346137 ;
Abstract
A glass substrate for a magnetic disk of the present invention is one in which a laser beam is irradiated on a magnetic recording surface side thereby forming a large number of protrusions thereon to form texture thereon, each of the protrusions having a convex shape, an optical absorption coefficient of a glass with respect to a wavelength of a laser beam at 266 nm being within a range of 20 to 2000 mm.sup.-1, the glass having a composition by weight of: