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. 03, 2002
Filed:
Sep. 08, 1999
Akira Murakami, Tokyo, JP;
Takeo Otagiri, Tokyo, JP;
Toshio Sekiba, Tokyo, JP;
Shizuo Suzuki, Tokyo, JP;
Takumi Yata, Tokyo, JP;
Tetsuya Saito, Tokyo, JP;
Jun Saito, Tokyo, JP;
Katsuya Nagakura, Tokyo, JP;
Tomomasa Takeuchi, Saitama-ken, JP;
Hoya Corporation, Tokyo, JP;
Abstract
There are disclosed a method of manufacturing a thin-plate glass having a good flatness with a high mass productivity and a method of manufacturing a high-quality and high-performance glass substrate for an information recording medium and a magnetic recording medium with a high mass productivity. A glass gob is press-formed between upper and lower dies to form a thin-plate glass. The press forming is finished when the inside of the thin-plate glass is at a softening point Ts or a higher temperature. Subsequently, warp modification pressing is performed to modify a warp of the thin-plate glass. The warp modification pressing is finished when the inside of the thin-plate glass is at a transition point Tg or a higher temperature.