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:
Aug. 30, 2011
Filed:
Nov. 19, 2008
Yoshihiko Ooeda, Kanagawa, JP;
Masayuki Ishikawa, Kanagawa, JP;
Yoshihiko Ooeda, Kanagawa, JP;
Masayuki Ishikawa, Kanagawa, JP;
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
Embodiments of the present invention provide a magnetic disk having a lubricating layer formed on the surface thereof, which meets all the requirements for adhesiveness, adequate flowability, and strong binding power. In a particular embodiment, a magnetic disk has a magnetic layer, a protective layer, and a lubricating layer which are formed on a non-magnetic substrate, which is characterized in that said lubricating layer is comprised of a lubricant containing a first ingredient and a second ingredient, said first ingredient as the main constituent being a first perfluoropolyether compound represented by the formula (1) below, which has a weight-average molecular weight of 500 to 6000 and a dispersity smaller than 1.3, and said second ingredient being a second perfluoropolyether compound which has a weight-average molecular weight of 500 to 6000 and has 6 to 10 hydroxyl groups (on average) in one molecule,Rt-Rf-Rt  (1)where, Rfdenotes a perfluoropolyether chain represented by the formula (2) and Rt denotes a terminal group represented by the formula (3),—CFO—[(CFCFO)—(CFO)]—CF—  (2)where, m and n each denote a natural number,