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:
Apr. 27, 2010
Filed:
Mar. 14, 2005
Hideki Isono, Tokyo, JP;
Shinji Eda, Tokyo, JP;
Kazuhiko Maeda, Tokyo, JP;
Naohiro Kamiya, Tokyo, JP;
Nobuyuki Eto, Tokyo, JP;
Hideki Isono, Tokyo, JP;
Shinji Eda, Tokyo, JP;
Kazuhiko Maeda, Tokyo, JP;
Naohiro Kamiya, Tokyo, JP;
Nobuyuki Eto, Tokyo, JP;
Hoya Corporation, Tokyo, JP;
Abstract
A magnetic disk glass substrate manufacturing method includes a step of polishing a surface of a glass substrate to a mirror surface, a gas heating process step of causing a heated atmosphere and the glass substrate to contact each other so as to heat the glass substrate at a temperature T, a step of causing a chemically strengthening salt melted exceeding a freezing temperature Tand the glass substrate to contact each other so as to chemically strengthen the glass substrate at a temperature T, a gas cooling process step of causing a gas coolant and the glass substrate to contact each other so as to cool the glass substrate to a temperature T, and a liquid cooling process step of causing a liquid coolant and the glass substrate to contact each other so as to cool the glass substrate to a temperature T, the above-mentioned steps being included in this order, wherein the temperature Tis set to a temperature less than the freezing temperature Tof the chemical strengthening salt in a gas cooling process.