Fuji Electric Co., Ltd.

Fuji Electric Device Technology Co., Ltd.

Kunihiro Imai

Takeshi Watanabe

Akira Furuta

Takako Matsumoto

Masami Kuroda

Hideki Kina

Kazuo Nimura

Kazuhiro Kusakawa

A magnetic recording medium includes a nonmagnetic substrate and at least a magnetic layer, a protective layer, and a lubricating layer provided on the nonmagnetic substrate. The magnetic recording medium is characterized in that the lubricating layer is formed of a lubricating agent represented by general formulas (1), (2) or (3), in which substituents R, R, R, and Rin the lubricating agent represent organic groups, at least one of the substituents Rand Rat the end part of the lubricating agent and the substituents Rand Rcontain a plurality of functional groups, and the shortest distance between the functional groups is a distance of three or more atoms, preferably five atoms. The magnetic recording medium may be used for a heat assisted recording method in which the temperature of the magnetic layer reaches 150&#xb0; C. to 200&#xb0; C. The magnetic recording medium is characterized in that the amount of the lubricating agent volatilized in the lubricating layer is less than 10% of the initial layer thickness.

Magnetic recording medium

A magnetic recording medium having high bonding capability between the surface lubricant and the diamond-like carbon (DLC) protective layer in the surface of the magnetic recording medium is disclosed. The lubricant is a fluorine-containing lubricant for magnetic recording media represented by the following formula (1), (2) or (3), wherein the substituents R, R, R, R, Rand Rin the terminal part of the lubricant each independently represent an organic group, and at least one of the substituents Rand R, at least one of the substituents Rand R, and at least one of the substituents Rand Reach have an isocyanate group: Also disclosed is a magnetic recording medium using the lubricant.

Lubricant for magnetic recording media, and magnetic recording medium using the lubricant

A magnetic recording medium for use in a thermally assisted recording system is disclosed. The magnetic recording medium comprises at least a magnetic layer, a protective layer and a lubricant layer formed on a nonmagnetic substrate, wherein a lubricant of the lubricant layer exhibits such a heat resistance that an amount of volatilization when the magnetic layer is heated to a temperature not lower than a temperature Tw is less than 1% with respect to an initial amount of the lubricant in an unheated condition. The present invention addresses a problem of the heat resistance performance of the lubricant for use in magnetic recording media and provides a magnetic recording medium exhibiting high heat resistance.

Magnetic recording medium for thermally assisted recording

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Nagano, Japan

Kunihiro Imai