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:
Mar. 26, 2013
Filed:
Oct. 21, 2010
Applicants:
Jun Endo, Chiyoda-ku, JP;
Tetsuya Nakashima, Chiyoda-ku, JP;
Inventors:
Jun Endo, Chiyoda-ku, JP;
Tetsuya Nakashima, Chiyoda-ku, JP;
Assignee:
Asahi Glass Company, Limited, Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B 5/84 (2006.01); C03B 25/00 (2006.01); G11B 5/62 (2006.01);
U.S. Cl.
CPC ...
Abstract
To provide a process to improve acid resistance of a glass substrate for an information recording medium. A process for producing a glass substrate for an information recording medium, comprising processing a glass formed into a plate by a float process, a down-draw method or a press method, wherein, in cooling of the glass in the last step where the glass has a temperature of at least its strain point, the time during which the glass temperature is at least its strain point and at most a temperature where the glass viscosity is 10dPa·s is at least 13 minutes.