The present invention relates to a magnetic recording medium in which a lubricant layer contains a compound A represented by general formula (1) and a compound B represented by general formula (2), satisfying (A/B)=0.2 to 3.0, and has an average thickness of 0.8 nm to 2 nm. R.sup.1—C.sub.6H.sub.4OCH.sub.2CH(OH)CH.sub.2OCH.sub.2—R.sup.2—CH.sub.2OCH.sub.2CH(OH)CH.sub.2OH . . . (1) (R.sup.1 is an alkoxy group having 1 to 4 carbon atoms. R.sup.2 is —CF.sub.2O(CF.sub.2CF.sub.2O).sub.x(CF.sub.2O).sub.yCF.sub.2— (x, y=0 to 15), —CF.sub.2CF.sub.2O(CF.sub.2CF.sub.2CF.sub.2O).sub.zCF.sub.2CF.sub.2— (z=1 to 15), —CF.sub.2CF.sub.2CF.sub.2O(CF.sub.2CF.sub.2CF.sub.2CF.sub.2).sub.nCF.sub.2CF.sub.2CF.sub.2— (n=0 to 4). HOCH.sub.2CF.sub.2CF.sub.2O(CF.sub.2CF.sub.2CF.sub.2O).sub.mCF.sub.2CF.sub.2CH.sub.2OCH.sub.2CH(OH)CH.sub.2OH . . . (2) (m is an integer).

A composition comprising a heat transfer portion and a lubricating portion, wherein the lubricating portion comprises one or more compounds according to formula (I): wherein W is independently selected from the group consisting of H, F, Cl, Br and I; Y is independently selected from the group consisting of F, Cl, Br and I; Z is independently selected from the group consisting of H, OH, (CW.sub.2).sub.PCW.sub.3, CY.sub.3, OCW.sub.3, O(CW.sub.2).sub.pCW.sub.3, OCW((CY.sub.2).sub.mCY.sub.3)CWCW.sub.2, polyalkylene glycol and polyolester; n is an integer from 2 to 250; m is an integer from 0 to 3; and p is an integer from 0 to 9.

A composition comprising a heat transfer portion and a lubricating portion, wherein the lubricating portion comprises one or more compounds according to formula (I): wherein W is independently selected from the group consisting of H, F, Cl, Br and I; Y is independently selected from the group consisting of F, Cl, Br and I; Z is independently selected from the group consisting of H, OH, (CW.sub.2).sub.PCW.sub.3, CY.sub.3, OCW.sub.3, O(CW.sub.2).sub.pCW.sub.3, OCW((CY.sub.2).sub.mCY.sub.3)CWCW.sub.2, polyalkylene glycol and polyolester; n is an integer from 2 to 250; m is an integer from 0 to 3; and p is an integer from 0 to 9.

A fluorine-containing ether compound represented by R.sup.1—R.sup.2—CH.sub.2—R.sup.3—CH.sub.2—R.sup.4—R.sup.5 is provided. (R.sup.3 is a perfluoropolyether chain; R.sup.1 and R.sup.5 are each independently any one of an alkyl group that may have a substituent, an organic group having at least one double bond or at least one triple bond, and a hydrogen atom; and —R.sup.2—CH.sub.2—R.sup.3 is represented by Formula (2), and R.sup.3—CH.sub.2—R.sup.4— is represented by Formula (3))
-[A]-[B]—O—CH.sub.2—R.sup.3  (2)
R.sup.3—CH.sub.2—O—[C]-[D]-  (3)
([A] is represented by Formula (4), [B] is represented by Formula (5), [C] is represented by Formula (6), [D] is represented by Formula (7), and in the formula, a and b are integers of 0 to 2, c is an integer of 2 to 5, d and f are integers of 0 to 2, and e is an integer of 2 to 5, and at least one of b and d in the formula is 1 or more) ##STR00001##

The present invention relates to compounds according to formula (Ia) or formula (Ib);

##STR00001##

wherein each W is independently selected from the group consisting of H, F, Cl, Br, I and (CY.sub.2).sub.mCY.sub.3; each Y is independently selected from the group consisting of F, Cl, Br and I; each Z is independently selected from the group consisting of H, OH, (CW.sub.2).sub.pCW.sub.3, CY.sub.3, OCW.sub.3, O(CW.sub.2).sub.pCW.sub.3, OCW((CY.sub.2).sub.mCY.sub.3)CWCW.sub.2, (CW.sub.2).sub.pOH, polyalkylene glycol and polyolester; n is an integer from 2 to 49; m is an integer from 0 to 3; p is an integer from 0 to 9; the molecular weight average (M.sub.W) is ≤5500; and the polydispersity index is ≤1.45; compositions comprising these compounds and methods for their production.

The present invention relates to compounds according to formula (Ia) or formula (Ib);

##STR00001##

wherein each W is independently selected from the group consisting of H, F, Cl, Br, I and (CY.sub.2).sub.mCY.sub.3; each Y is independently selected from the group consisting of F, Cl, Br and I; each Z is independently selected from the group consisting of H, OH, (CW.sub.2).sub.pCW.sub.3, CY.sub.3, OCW.sub.3, O(CW.sub.2).sub.pCW.sub.3, OCW((CY.sub.2).sub.mCY.sub.3)CWCW.sub.2, (CW.sub.2).sub.pOH, polyalkylene glycol and polyolester; n is an integer from 2 to 49; m is an integer from 0 to 3; p is an integer from 0 to 9; the molecular weight average (M.sub.W) is ≤5500; and the polydispersity index is ≤1.45; compositions comprising these compounds and methods for their production.

Provided herein is a lubricant including a compound of Formula I
L-(CF.sub.2CF.sub.2O).sub.n—CF.sub.2CH.sub.2O—N—OCH.sub.2CF.sub.2O—(CF.sub.2CF.sub.2O).sub.m-M  (Formula I)
wherein L is selected from the group consisting of ##STR00001## M is selected from the group consisting of ##STR00002##
wherein each instance of R.sup.1, R.sup.2, and R.sup.3 is independently selected from the group consisting of hydroxyl, alkoxyl, carbocycyl, phenyl, heterocycyl, piperonyl, carboxyl, alkylamido, acetamido, carbamoyl, N-alkylcarbamoyl, N,N-dialkylcarbamoyl, 2,3-dihydroxy-1-propoxyl, acryloyl, alkacryloyl, methacryloyl, a substituent of methyl methacrylate, and a substituent of glycidyl ether; and
wherein n≧1, m≧1, and n and m are the same or different.

A lubricant including a plurality of segments including a divalent center segment and two sidechain segments, each including a perfluoroalkyl ether moieties is provided in which a dewetting thickness of the lubricant may be determined based in-part on a segment weight average molecular weight of the segments. A magnetic recording medium and a magnetic data storage system including the lubricant are also provided.

A lubricant including a plurality of segments including a divalent center segment and two sidechain segments, each including a perfluoroalkyl ether moieties is provided in which a dewetting thickness of the lubricant may be determined based in-part on a segment weight average molecular weight of the segments. A magnetic recording medium and a magnetic data storage system including the lubricant are also provided.

Some variations provide a low-adhesion coating comprising a continuous matrix containing a first component, a plurality of inclusions containing a second component, and a solid-state lubricant distributed within the coating, wherein one of the first component or the second component is a low-surface-energy polymer, and the other of the first component or the second component is a hygroscopic material. The solid-state lubricant may be selected from graphite, graphene, molybdenum disulfide, tungsten disulfide, hexagonal boron nitride, or poly(tetrafluoroethylene) or other fluoropolymers. The solid-state lubricant particles may be coated with a metal selected from cadmium, lead, tin, zinc, copper, nickel, or alloys containing one or more of these metals. The solid-state lubricant is typically characterized by an average particle size from about 0.1 μm to about 500 μm. The solid-state lubricant is preferably distributed throughout the coating.