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:
Sep. 28, 2010
Filed:
Jun. 03, 2009
Kensuke Nagai, Chiyoda-ku, JP;
Tetsuya Nakashima, Chiyoda-ku, JP;
Kei Maeda, Chiyoda-ku, JP;
Tatsuo Nagashima, Chiyoda-ku, JP;
Kensuke Nagai, Chiyoda-ku, JP;
Tetsuya Nakashima, Chiyoda-ku, JP;
Kei Maeda, Chiyoda-ku, JP;
Tatsuo Nagashima, Chiyoda-ku, JP;
Asahi Glass Company, Limited, Tokyo, JP;
Abstract
To provide a substrate glass for data storage medium which is excellent in weather resistance even when no additional treatment such as chemical reinforcement treatment is applied and less susceptible to a whitening phenomenon and which has a glass transition temperature of at least 680° C. and is excellent in acid resistance. A substrate glass for data storage medium, which comprises, as represented by mass %, from 47 to 60% of SiO, from 8 to 20% of AlO, from 0 to 8% of MgO, from 0 to 6% of CaO, from 1 to 18% of SrO, from 0 to 13% of BaO, from 1 to 6% of TiO, from 1 to 5% of ZrO, from 2 to 8% of NaO and from 1 to 15% of KO and which has a glass transition temperature of at least 680° C.