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:
Jun. 28, 2005
Filed:
Oct. 24, 2002
Yoshihito Osawa, Nagano, JP;
Shinji Shirai, Nagano, JP;
Masayuki Ishikawa, Nagano, JP;
Fuji Electric Co., Ltd., Kawasaki, JP;
Abstract
A method to refine a lubricant on a magnetic recording medium includes a compound A including a perfluoropolyether molecular structure having two hydroxyl groups at each of two ends and a compound B including the perfluoropolyether molecular structure having one hydroxyl group at each of two ends. The method includes putting the lubricant into a pressure vessel set at a pressure and a temperature and removing the compound B dissolved in an extracting medium of a supercritical carbon dioxide fluid that flows at a predetermined rate through the pressure vessel held at a predetermined temperature and at a predetermined pressure. The method performs recovering the compound A dissolved in the extracting medium that flows through the pressure vessel held at the predetermined pressure and at a temperature lower than the predetermined temperature or at the predetermined temperature and at a pressure higher than the predetermined pressure.