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:
Feb. 18, 2014
Filed:
Dec. 20, 2011
Hideki Isono, Shinjuku-ku, JP;
Kinobu Osakabe, Shinjuku-ku, JP;
Katsuyuki Iwata, Shinjuku-ku, JP;
Mikio Ikenishi, Shinjuku-ku, JP;
Naomi Matsumoto, Shinjuku-ku, JP;
Hideki Isono, Shinjuku-ku, JP;
Kinobu Osakabe, Shinjuku-ku, JP;
Katsuyuki Iwata, Shinjuku-ku, JP;
Mikio Ikenishi, Shinjuku-ku, JP;
Naomi Matsumoto, Shinjuku-ku, JP;
Hoya Corporation, Tokyo, JP;
Abstract
An aspect of the present invention relates to a glass substrate for a magnetic recording medium, which is comprised of glass with a glass transition temperature of equal to or greater than 600° C., an average coefficient of linear expansion at 100 to 300° C. of equal to or greater than 70×10/° C., a Young's modulus of equal to or greater than 81 GPa, a specific modulus of elasticity of equal to or greater than 30 MNm/kg, and a fracture toughness value of equal to or greater than 0.9 MPa·m.