Patent classifications
G11B5/7266
CARBON OVERCOAT SURFACE TREATMENT
Systems and methods for treating a carbon overcoat surface are described. In one embodiment, the method may include depositing a magnetic recording layer over a substrate, depositing a carbon overcoat layer over the magnetic recording layer, and exposing a carbon overcoat layer to water in gas phase after the carbon overcoat layer is deposited on the magnetic recording layer. In some cases, the method may include depositing a lubricant over the outer surface of the carbon overcoat after exposing the carbon overcoat layer to the water in gas phase.
Anti-reflection data storage medium
An anti-reflection storage medium. The anti-reflection storage medium includes a storage layer and a protective overcoat disposed over the storage later. The protective overcoat has a first refractive index value that is matched to a second refractive index value of the storage layer to reduce reflection of incident light applied to the storage medium when data is written to the storage layer of the storage medium.
FLUORINE-CONTAINING ETHER COMPOUND, LUBRICANT FOR MAGNETIC RECORDING MEDIUM, AND MAGNETIC RECORDING MEDIUM
A fluorine-containing ether compound represented by Formula (1) is provided.
R.sup.1R.sup.2CH.sub.2R.sup.3CH.sub.2R.sup.4R.sup.5 (1)
(In Formula (1), R.sup.1 and R.sup.5 each represents a group having a heterocyclic ring and may be the same as or different from each other, R.sup.2 and R.sup.4 each represents a divalent linking group having a polar group and play be the same as or different from each other, and R.sup.3 represents a perfluoropolyether chain.)
CHEMISORBED LUBRICANTS FOR DATA STORAGE DEVICES
A lubricant adheres to a magnetic recording medium via at least one of chemisorption or bonding, and contains a perfluorinated polyether attached to or terminated with a functional group that is phosphonic acid, silanol or carboxylic acid, and may be:
R.sub.1R.sub.fR.sub.1 where R.sub.f is CF.sub.2O(CF.sub.2CF.sub.2CF.sub.2CF.sub.2O).sub.n, CF.sub.2O(CF.sub.2CF.sub.2CF.sub.2O).sub.nCF.sub.2, CF.sub.2O[CF(CF.sub.3)CF.sub.2O].sub.nCF.sub.2, CF.sub.2O(CF.sub.2CF.sub.2O).sub.m(CF.sub.2O).sub.nCF.sub.2, CF.sub.2O(CF.sub.2CF.sub.2O).sub.nCF.sub.2, n, m is from 1 to 100 and R.sub.1 is the functional group. A lubricant is formed from a multiple ether segments according to formula:
Re.sup.1Rb.sup.1-Ri-Rc-Ri-Rb.sup.2Re.sup.2; where Rc includes perfluoroalkyl ether, Rb.sup.1 and Rb.sup.2 are, independently, a sidechain segment including a perfluoroalkyl ether, optional Ri independently is a divalent linking segment including a functional group including elements from periodic table Group 13-17, and of Re.sup.1 and Re.sup.2 are phosphonic acid, silanol or carboxylic acid. Lubricant synthesis includes reacting a perfluorinated polyether with a halogenated functional group, selected from phosphonic acid, silanol or carboxylic acid.
TWO DIMENSIONAL AMORPHOUS CARBON AS OVERCOAT FOR HEAT ASSISTED MAGNETIC RECORDING MEDIA
A recording device comprising an overcoat layer, wherein the overcoat layer comprises an amorphous carbon overcoat layer having a crystallinity (C)0.8.
Magnetic recording medium, and magnetic recording and reproducing apparatus
A magnetic recording medium which is capable of effectively preventing a surface thereof from being contaminated, and is capable of preventing a contaminant thereon from adhering (being transferred) to a magnetic head, and a magnetic recording and reproducing apparatus including the magnetic recording medium are provided, A carbon protective layer of the magnetic recording medium is nitrided, and as a lubricant a compound A expressed by the following General Formula (1) and a compound B expressed by the following General Formula (2) are mixed and used.
R.sup.1C.sub.6H.sub.4OCH.sub.2CH(OH)CH.sub.2OCH.sub.2R.sup.2CH.sub.2OCH.sub.2CH(OH)CH.sub.2OH(1)
CH.sub.2(OH)CH(OH)CH.sub.2OCH.sub.2CF.sub.2CF.sub.2(OCF.sub.2CF.sub.2CF.sub.2).sub.mOCF.sub.2CF.sub.2CH.sub.2OCH.sub.2CH(OH)CH.sub.2OH(2)
Magnetic recording medium and magnetic recording and reproducing apparatus
A magnetic recording medium 11 in which the outermost surface of a protective layer 3 on a lubricant layer 4 side contains carbon and nitrogen of 10 atomic % to 90 atomic %, the lubricant layer 4 is formed by being in contact with the outermost surface, and contains a compound A of Formula (1) and a compound B of Formula (2), a mass ratio (A/B) of the compound A with respect to the compound B is 0.2 to 0.3, the average molecular weights of the compounds A and B are 1,500 to 2,000 and 1,300 to 2,400, respectively, and the average film thickness is 0.5 nm to 2 nm.
R1-C.sub.6H.sub.4OCH.sub.2CH(OH)CH.sub.2OCH.sub.2R2-CH.sub.2OCH.sub.2CH(OH)CH.sub.2OH (1) (R1 is an alkoxy group having 1 to 4 carbon atoms. R2 is CF.sub.2O(CF.sub.2CF.sub.2O)x(CF.sub.2O)yCF.sub.2).
HOCH.sub.2CF.sub.2CF.sub.2O(CF.sub.2CF.sub.2CF.sub.2O)mCF.sub.2CF.sub.2CH.sub.2OCH.sub.2CH(OH)CH.sub.2OH (2)
Magnetic recording medium and magnetic recording and reproducing apparatus
In a magnetic recording medium of the present invention, an outermost surface of a protective layer 3 on a lubricant layer 4 side contains carbon and nitrogen in a range of 50 atomic % to 90 atomic %, and the lubricant layer 4 is formed by being in contact with the outermost surface, contains compounds A to C represented in the below general formulas (1) to (3) described below, and has a film thickness of 0.5 nm to 2 nm.
R1-C.sub.6H.sub.4OCH.sub.2CH(OH)CH.sub.2OCH.sub.2R2-CH.sub.2OCH.sub.2CH(OH)CH.sub.2OH (1),
CH.sub.2(OH)CH(OH)CH.sub.2OCH.sub.2CF.sub.2CF.sub.2(OCF.sub.2CF.sub.2CF.sub.2).sub.mOCF.sub.2CF.sub.2CH.sub.2OCH.sub.2CH(OH)CH.sub.2OH (2),
HOCH.sub.2CF.sub.2CF.sub.2O(CF.sub.2CF.sub.2CF.sub.2O)sCF.sub.2CF.sub.2CH.sub.2OCH.sub.2CH(OH)CH.sub.2OH (3)
Fluoropolyether compound, lubricant, and magnetic disk
The disclosure provides a fluoropolyether compound represented by formula (1):
R.sup.1CH.sub.2R.sup.2CH.sub.2R.sup.3
wherein R.sup.1 is C.sub.1-C.sub.10 alkoxy; R.sup.2 is (CF.sub.2).sub.pO(CF.sub.2O).sub.x(CF.sub.2CF.sub.2O).sub.y(CF.sub.2CF.sub.2CF.sub.2O).sub.z(CF.sub.2CF.sub.2CF.sub.2CF.sub.2O).sub.w(CF.sub.2).sub.p; x and y are each a real number of 0 to 30; z is a real number of 0 to 30; w is a real number of 0 to 20; p is an integer of 1 to 3; R.sup.3 is OCH.sub.2CH(OH)CH.sub.2OH, OCH.sub.2CH(OH)CH.sub.2OCH.sub.2CH(OH)CH.sub.2OH, O(CH.sub.2).sub.mOH, or OCH.sub.2(OH)CHCH.sub.2OC.sub.6H.sub.4R.sup.4; m is an integer of 2 to 8; and R.sup.4 is hydrogen, C.sub.1-C.sub.4 alkoxy, amino, or an amide residue; and also provides a lubricant having the compound and a magnetic disk.
ANTI-REFLECTION DATA STORAGE MEDIUM
An anti-reflection storage medium. The anti-reflection storage medium includes a storage layer and a protective overcoat disposed over the storage later. The protective overcoat has a first refractive index value that is matched to a second refractive index value of the storage layer to reduce reflection of incident light applied to the storage medium when data is written to the storage layer of the storage medium.