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. 17, 2012
Filed:
Feb. 01, 2010
Mikio Ikenishi, Tokyo, JP;
Atsuko Morita, Tokyo, JP;
Xuelu Zou, Tokyo, JP;
Hoya Corporation, Tokyo, JP;
Abstract
Disclosed are a glass substrate for an information recording medium, having excellent scratch resistance and a light weight and having high fracture toughness, the glass substrate having a fragility index value, measured in water, of 12 μmor less or having a fragility index value, measured in an atmosphere having a dew point of −5° C. or lower, of 7 μmor less, or the glass substrate comprising, by mol %, 40 to 75% of SiO, 2 to 45% of BOand/or AlOand 0 to 40% of R'O in which R′ is at least one member selected from the group consisting of Li, Na and K), wherein the total content of SiO, BO, AlOand R′O is at least 90 mol %, and a magnetic information recording medium comprising a magnetic recording layer formed on the glass substrate.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile