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. 28, 2002
Filed:
Mar. 31, 2000
Takemi Miyamoto, Tokyo, JP;
Hoya Corporation, Tokyo, JP;
Abstract
In a method of manufacturing a glass substrate for a magnetic recording medium for forming a predetermined roughness, a principal surface of the glass substrate is precisely polished by the use of polishing material containing free abrasive grain. Remaining stress distribution for a portion of a polishing trace due to the free abrasive grain is generated on the surface of the glass substrate. A surface process is performed for at least the principal surface of the glass substrate by the use of hydrosilicofluoric acid. A portion having relatively high remaining distortion in the generated remaining stress distribution is decided as an island portion. The glass substrate is heated after precisely polishing before performing the surface process by the use of the hydrosilicofluoric acid.