A method refines a lubricant comprising a compound having a perfluoropolyether structure via supercritical extraction. A lubricant is refined using the method and a magnetic recording medium that utilizes the refined lubricant. The refined lubricant exhibits excellent lubrication performance and long term stability in the magnetic recording medium. In one embodiment of the supercritical extraction, the lubricant contacts an extracting medium of supercritical carbon dioxide under a predetermined condition in a pressure vessel to remove ionic impurities and perfluoropolyether compounds having a weak polarity terminal group contained in the lubricant.

 
Web www.patentalert.com

> Calibration procedure for investigating biological systems

~ 00337