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. 16, 2014
Filed:
Apr. 26, 2007
Applicants:
Yoshiaki Oshima, Wakayama, JP;
Norihito Yamaguchi, Wakayama, JP;
Haruhiko Doi, Wakayama, JP;
Inventors:
Assignee:
Kao Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B24D 11/00 (2006.01); C09C 1/68 (2006.01); C09K 3/14 (2006.01); C09G 1/02 (2006.01);
U.S. Cl.
CPC ...
C09G 1/02 (2013.01); C09K 3/1409 (2013.01); C09K 3/1463 (2013.01);
Abstract
A polishing composition for a magnetic disk substrate of the present invention includes water, silica particles, and at least one or more selected from an acid, a salt of the acid, and an oxidizing agent. The silica particles are observed with a transmission electron microscope to measure a maximum diameter and a projected area of each particle, and a value obtained by dividing the area of a circle whose diameter is the maximum diameter of a silica particle by the projected area of the silica particle and multiplying the result by 100, is in the range of 100 to 130.