An object is to provide a magnetic recording medium having excellent traveling stability and a thin total thickness.

The present technology provides a tape-shaped magnetic recording medium including: a magnetic layer; an underlayer; a base layer; and a back layer, in which a surface on a side of the magnetic layer has a kurtosis of 3.0 or more, a surface on a side of the back layer has a kurtosis of 2.0 or more, the surface on the magnetic layer side has arithmetic average roughness R.sub.a of 2.5 nm or less, the base layer includes a polyester as a main component, the magnetic recording medium has an average thickness t.sub.T of 5.6 μm or less, the magnetic recording medium includes a lubricant, the lubricant includes a fatty acid and a fatty acid ester, and a mass ratio between the fatty acid and the fatty acid ester extracted with hexane satisfies fatty acid/fatty acid ester ≤0.6, and the magnetic recording medium has pores, and the pores have an average diameter of 6 nm or more and 11 nm or less when the diameters of the pores are measured in a state where the lubricant has been removed from the magnetic recording medium and the magnetic recording medium has been dried.

A low friction wear surface with a coefficient of friction in the superlubric regime under a sliding and rolling movement. The low friction wear surface includes molybdenum disulfide and graphene oxide on a first wear surface with a tribolayer formed on a rough steel counter surface during the sliding and rolling movement. Methods of producing the low friction wear surface are also provided.

A multidentate lubricant comprising an anchoring moiety Ra attached to a plurality of sidechain moieties —(Rb—Re) according to the general formula: Ra—(Rb—Re).sub.x; wherein Ra is a multivalent radical of valance x; and each sidechain includes a perfluoroethyl ether moiety. The lubricant can be used in conjunction with a magnetic recording medium and/or a magnetic data storage system.

A fluorine-containing ether compound represented by formula (1) shown below.
R.sup.4—CH.sub.2—R.sup.3—CH.sub.2—R.sup.2—CH.sub.2—R.sup.1—CH.sub.2—R.sup.2—CH.sub.2—R.sup.3—CH.sub.2—R.sup.4  (1)
(In formula (1), R.sup.1 and R.sup.3 represent different perfluoropolyether chains, R.sup.2 represents a linking group containing one or more polar groups, and R.sup.4 represents a terminal group containing two or more polar groups.)

A fluorine-containing ether compound represented by the following formula (1) is provided.

##STR00001##

(In the formula (1), R.sup.1 is an alkoxy group having 1 to 10 carbon atoms, R.sup.2 is a perfluoropolyether chain, R.sup.3 is —OCH.sub.2CH(OH)CH.sub.2O(CH.sub.2).sub.mOH (m in the formula is an integer of 2 to 4).)

High temperature lubricants for magnetic media are provided. One such lubricant includes fluoroalkyl, fluoroalkenyl, perfluoroalkyl, or perfluoroalkyl ether segments, anchoring functional groups engageable with a protective overcoat of a magnetic recording media, and cyclic functional groups. The lubricants can be used in conjunction with a magnetic recording medium and/or a magnetic data storage system.

What is provided is a fluorine-containing ether compound represented by the following formula. R.sup.1—CH.sub.2—R.sup.2—CH.sub.2—OCH.sub.2CH(OH)CH.sub.2O—CH.sub.2—R.sup.3—CH.sub.2—R.sup.4 (In the formula, R.sup.2 and R.sup.3 are perfluoropolyether chains, and R.sup.1 and R.sup.4 are terminal groups having two or three polar groups, in which individual polar groups are bound to different carbon atoms and the carbon atoms to which the polar groups are bound are bound to each other via a linking group having a carbon atom to which the polar groups are not bound).

The fluorine-containing ether compound is represented by the following formula (1): R.sup.1—R.sup.2—CH.sub.2—R.sup.3—CH.sub.2—R.sup.4. In the formula (1), R.sup.1 is represented by the following formula (2), R.sup.2 is represented by the following formula (3), R.sup.3 is a perfluoropolyether chain, and R.sup.4 is an organic end group different from R.sup.1—R.sup.2— and contains two or three polar groups, wherein each polar group is bonded to a different carbon atom, and the carbon atoms to which the polar groups are bonded are bonded to one another via a linking group containing a carbon atom to which the polar group is not bonded. In the formula (2), R.sup.5 is an alkoxy group selected from the group consisting of a methoxy, an ethoxy and a propoxy group. In the formula (3), w is 2 or 3. ##STR00001##

Provided is a fluorine-containing ether compound capable of forming a lubricant layer having excellent wear resistance even when the thickness is thin, and suitable as a material of a lubricant for a magnetic recording medium. The fluorine-containing ether compound is a compound represented by the following formula (1): R.sup.1—R.sup.2—CH.sub.2—R.sup.3—CH.sub.2—R.sup.4—R.sup.5; wherein R.sup.3 is a perfluoropolyether chain; R.sup.1 is a terminal group bonded to R.sup.2; R.sup.5 is a terminal group bonded to R.sup.4; R.sup.1 is an alkenyl group or an alkynyl group; R.sup.5 is a group containing a heterocyclic ring; R.sup.2 is represented by the following formula (2); R.sup.4 is represented by the following formula (3); and a in the formula (2) and b in the formula (3) are each independently an integer of 1 to 3. ##STR00001##

A fluorine-containing ether compound represented by Formula (1) is provided,
R.sup.1—R.sup.2—CH.sub.2—R.sup.3—CH.sub.2—R.sup.4  (1)
(In Formula (1), R.sup.1 is an alkyl group that may have a substituent, R.sup.2 is a divalent linking group bonded to R.sup.1 via an ethereal oxygen, R.sup.3 is a perfluoropolyether chain, and R.sup.4 is an end group which is different from R.sup.1-R.sup.2 and includes two or three polar groups, in which each of the polar groups is bonded to a different carbon atom, and the carbon atoms bonded to the polar groups are bonded to each other via a linking group containing a carbon atom not bonded to the polar groups.).