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. 17, 2015
Filed:
Jul. 19, 2011
Nobuhiro Iwamoto, Yamaguchi, JP;
Nobuaki Mukai, Yamaguchi, JP;
Kazutaka Arai, Yamaguchi, JP;
Ryuji Kotani, Yamaguchi, JP;
Nobuhiro Iwamoto, Yamaguchi, JP;
Nobuaki Mukai, Yamaguchi, JP;
Kazutaka Arai, Yamaguchi, JP;
Ryuji Kotani, Yamaguchi, JP;
Toyo Kohan Co., Ltd, Tokyo, JP;
Kohan Kogyo Co., Ltd., Yamaguchi, JP;
Abstract
Provided are a rinsing agent to produce a hard disk substrate free from remaining abrasive grains as well as a pit defect on the surface thereof and a method for production of a hard disk substrate using such a rinsing agent. A rinsing agent of the present invention is rinsing solution containing colloidal silica as abrasive grains. Letting that the colloidal silica abrasive grains have a concentration C and an average grain size R (C and R are represented in weight % and nm, respectively), the concentration C and the average grain size R of the colloidal silica abrasive grains have a relation matching the following Expression (1):12.2C+18.2  (1).