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:
Nov. 27, 2007
Filed:
Feb. 11, 2004
Applicants:
Hirokazu Tajima, Osaka, JP;
Tamaki Horisaka, Osaka, JP;
Inventors:
Hirokazu Tajima, Osaka, JP;
Tamaki Horisaka, Osaka, JP;
Assignee:
Hoya Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B24B 7/30 (2006.01); B24D 11/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A polishing pad is used when a surface of a glass workpiece is polished for manufacturing a glass substrate of information recording medium. The polishing pad has a nap layer. The nap layer includes an inner layer that contains a plurality of closed cells, and an outer layer. A plurality of pores are formed on the surface of the outer layer. The sizes of the pores are minute compared to those of the closed cells.