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:
Jul. 07, 2015
Filed:
Mar. 15, 2011
Applicant:
Hazuki Nakae, Kyoto, JP;
Inventor:
Hazuki Nakae, Kyoto, JP;
Assignee:
Hoya Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 5/84 (2006.01); C03C 19/00 (2006.01); C09G 1/02 (2006.01);
U.S. Cl.
CPC ...
G11B 5/8404 (2013.01); Y10T 428/24355 (2015.01); C09G 1/02 (2013.01); C03C 19/00 (2013.01);
Abstract
Disclosed is a method of producing a glass substrate for an information recording medium including a precision polishing step of using a polishing material containing colloidal silica and performing precision polishing, under acidic conditions, on a glass material in which the amount of iron adhered on the surface is 0.5 ng/cmor less and the surface roughness Ra is 1 nm or less. Additionally disclosed is a glass substrate for an information recording medium produced by the foregoing method of producing a glass substrate for an information recording medium.