Patents
Literature
Hiro is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Hiro

570results about "Protective coatings for layers" patented technology

Anti-ferromagnetically coupled granular-continuous magnetic recording media

An anti-ferromagnetically coupled, granular-continuous (“AFC-GC”) magnetic recording medium having increased thermal stability, writability, and signal-to-medium noise ratio (“SMNR”), comprising a layer stack including, in sequence from a surface of a non-magnetic substrate: (a) a continuous ferromagnetic stabilizing layer; (b) a non-magnetic spacer layer; and (c) a granular ferromagnetic recording layer; wherein: (i) the continuous ferromagnetic stabilizing and granular ferromagnetic recording layers are anti-ferromagnetically coupled across the non-magnetic spacer layer, the amount of anti-ferromagnetic coupling preselected to ensure magnetic relaxation after writing; (ii) lateral interactions in the granular, ferromagnetic recording layer are substantially completely eliminated or suppressed; and (iii) the exchange coupling strength in the continuous, ferromagnetic stabilizing layer is preselected to be slightly larger than the strength of the anti-ferromagnetic coupling provided by the non-magnetic spacer layer to thereby enhance thermal stability of the recording bits.
Owner:SEAGATE TECH LLC

Magnetic tape device and head tracking servo method

The magnetic tape device includes: a magnetic tape; and a servo head, in which a magnetic tape transportation speed of the magnetic tape device is equal to or lower than 18 m / sec, the servo head is a TMR head, the magnetic tape includes a non-magnetic support, and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, the magnetic layer includes a servo pattern, the magnetic layer includes one or more components selected from the group consisting of fatty acid and fatty acid amide, and a C—H derived C concentration calculated from a C—H peak area ratio of C1s spectra obtained by X-ray photoelectron spectroscopic analysis performed on a surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is 45 to 65 atom %.
Owner:FUJIFILM CORP

Magnetic recording medium and magnetic recording and reproducing device

ActiveUS20190103134A1Excellent electromagnetic conversion characteristicAvoid it happening againMaterials with ironProtective coatings for layersIn planeX-ray
Provided are a magnetic recording medium, in which a magnetic layer includes ferromagnetic hexagonal ferrite powder, a binding agent, and an oxide abrasive, an intensity ratio Int(110) / Int(114) obtained by an X-ray diffraction analysis of the magnetic layer by using an In-Plane method is 0.5 to 4.0, a vertical squareness ratio of the magnetic recording medium is 0.65 to 1.00, a coefficient of friction measured regarding a base portion of a surface of the magnetic layer is equal to or smaller than 0.30, and an average particle diameter of the oxide abrasive obtained from a secondary ion image obtained by irradiating the surface of the magnetic layer with a focused ion beam is 0.04 μm to 0.08 μm, and a magnetic recording and reproducing device including this magnetic recording medium.
Owner:FUJIFILM CORP

Magnetic tape

Provided is a magnetic tape in which a thickness of a back coating layer is equal to or smaller than 0.20 μm, a C—H derived C concentration calculated from a C—H peak area ratio of C1s spectra obtained by X-ray photoelectron spectroscopic analysis performed on the surface of the back coating layer at a photoelectron take-off angle of 10 degrees, is equal to or greater than 35 atom %, full widths at half maximum of spacing distribution measured by optical interferometry regarding the surface of the back coating layer before and after performing a vacuum heating with respect to the magnetic tape are respectively greater than 0 nm and equal to or smaller than 10.0 nm, and a difference between a spacing measured after performing the vacuum heating and a spacing measured before performing the vacuum heating is greater than 0 nm and equal to or smaller than 8.0 nm.
Owner:FUJIFILM CORP

Magnetic recording medium

A magnetic recording medium of the present invention includes a non-magnetic substrate, and a magnetic layer containing a magnetic powder. The magnetic powder is constituted by an ε-iron oxide powder. The magnetic layer has a squareness in a thickness direction of 0.65 or more. In a differential curve obtained by differentiating a hysteresis curve in the thickness direction of the magnetic layer, two or more peaks are present. In a case where, out of peaks in the same direction among the above-described peaks, a local maximum of a largest peak in a magnetic field range of +500 oersted [Oe] or more is taken as P1 and a local maximum of a largest peak in a magnetic field range of −500 oersted [Oe] or more and less than +500 oersted [Oe] is taken as P2, a relationship below is satisfied:0.25≦P2 / P1≦0.60.
Owner:MAXELL HLDG LTD

Magnetic tape device and head tracking servo method

The magnetic tape device includes: a magnetic tape; and a servo head, in which the servo head is a TMR head, the magnetic tape includes a non-magnetic support, and a magnetic layer including ferromagnetic powder, a binding agent, and fatty acid ester on the non-magnetic support, the magnetic layer includes a servo pattern, full widths at half maximum of spacing distribution measured by optical interferometry regarding a surface of the magnetic layer before and after performing a vacuum heating with respect to the magnetic tape are greater than 0 nm and equal to or smaller than 7.0 nm, and a difference between a spacing measured by optical interferometry regarding the surface of the magnetic layer after performing the vacuum heating with respect to the magnetic tape and a spacing measured before performing the vacuum heating is greater than 0 nm and equal to or smaller than 9.0 nm.
Owner:FUJIFILM CORP

Ionic liquid, lubricant, and magnetic recording medium

A lubricant including an ionic liquid, which includes a conjugate acid (B+) and a conjugate base (X−), and is protic, wherein the conjugate acid includes a straight-chain hydrocarbon group having 10 or more carbon atoms, and wherein the conjugate base is represented by the following general formula (1):where n is an integer of from 0 to 6 in the general formula (1).
Owner:DEXERIALS CORP

Ionic liquid, lubricant, and magnetic recording medium

A lubricant including: an ionic liquid, which includes a conjugate acid (B+) and a conjugate base (X−), and is protic, wherein the ionic liquid is represented by the following general formula (1), and wherein the conjugate base is a conjugate base of sulfonic acid, a conjugate base of sulfonimide, or a conjugate base of trisulfonylmethide:where R1 and R2 each represent a hydrogen atom or R1 and R2 form a benzene ring together with carbon atoms to which R1 and R2 are bonded, R3 represents a to straight-chain hydrocarbon group having 10 or more carbon atoms, and R4 represents a hydrogen atom or a hydrocarbon group in the general formula (1).
Owner:DEXERIALS CORP

Magnetic tape

The magnetic tape includes a non-magnetic support; a magnetic layer including ferromagnetic powder and a binding agent on one surface side of the non-magnetic support; and a back coating layer including non-magnetic powder and a binding agent on the other surface side of the non-magnetic support, in which a thickness of the back coating layer is equal to or smaller than 0.30 μm, a logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the back coating layer is equal to or smaller than 0.060, and a contact angle with respect to 1-bromonaphthalene measured regarding a surface of the back coating layer is 15.0° to 30.0°.
Owner:FUJIFILM CORP

Lubricant for magnetic disk and magnetic disk

A lubricant for a magnetic disk that is excellent in heat resistance and is suitably used in a magnetic disk to be mounted on a magnetic recording device of a thermally assisted magnetic recording system and a magnetic disk provided with a lubricant layer containing this lubricant. The lubricant for a magnetic disk contains a compound where perfluoropolyether groups each having a perfluoropolyether main chain in its structure and a phosphazene ring at an end are linked to each other through a linking group. The linking group is an aliphatic group or a phosphazene ring. In a magnetic disk having at least a magnetic recording layer, a protective layer, and a lubricant layer on a substrate, the lubricant layer contains the lubricant for a magnetic disk.
Owner:WESTERN DIGITAL TECH INC

Lubricating oil

The invention provides a lube oil which exhibits low vapor pressure despite having low viscosity, is non-flammable, exhibits excellent heat resistance, has tribological characteristics equivalent to those of conventional hydrocarbon-based lube oils, and can be used for a long time under very severe conditions such as high temperature and vacuum. The lube oil contains, as a base oil, an ionic liquid formed of a cation and an anion and having an ion concentration of 1 mol / dm3 or more.
Owner:IDEMITSU KOSAN CO LTD +1

Magnetic disk comprising a first carbon overcoat having a high SP3 content and a second carbon overcoat having a low SP3 content

A method for making a magnetic disk comprises forming first and second protective carbon layers on a magnetic layer. The first protective carbon layer is predominantly SP3 carbon. The second protective carbon layer comprises about 50% or less SP3 carbon. The second protective carbon layer is very thin, e.g. between 0.1 and 1.0 nm thick. A lubricant layer (e.g. a perfluoropolyether lubricant) is applied to the second protective carbon layer. The second protective carbon layer facilitates improved cooperation between lubricant and the disk.
Owner:WESTERN DIGITAL TECH INC

Systems and Methods for Surface Modification by Filtered Cathodic Vacuum Arc

Provided are filtered cathodic vacuum arc systems useful for modifying a surface of a substrate (e.g. depositing a thin film of a material onto a surface of a substrate and / or implanting a material into the near-surface region of a substrate). The systems are configured to stabilize a do arc discharge plasma from an arc source. Also provided are methods for modifying a surface of a substrate, which in some cases includes depositing a material onto a surface of a substrate, in some cases includes implanting a material into the near-surface region of a substrate, and in some cases includes both depositing a material onto a surface of a substrate and implanting a material into the near-surface region of a substrate using the subject cathodic arc systems. In addition, magnetic recording media produced by the subject systems and methods are provided.
Owner:NAT UNIV OF SINGAPORE +1

Absorption enhanced media for energy assisted magnetic recording

A magnetic recording media is disclosed. The media comprises a substrate, a recording layer disposed over the substrate, and a metallic layer disposed between the recording layer and the substrate. The recording layer is configured to receive an electromagnetic radiation, absorb a first portion of the electromagnetic radiation, and transmit a second portion of the electromagnetic radiation. The metallic layer comprises a non-magnetic metal and configured to reflect at least some of the second portion of the electromagnetic radiation towards the recording layer.
Owner:WESTERN DIGITAL TECH INC

Perpendicular magnetic recording medium and process for manufacture thereof

An object of the present invention is to provide a perpendicular magnetic recording medium the SNR of which is improved by reducing noise thought to be due to an auxiliary recording layer so that a higher recording density can be achieved, and a method of manufacturing the same.In order to achieve the above object, a representative configuration of a perpendicular magnetic recording medium 100 according to the present invention includes, on a base, at least a magnetic recording layer 122 having a granular structure in which a non-magnetic grain boundary portion is formed between crystal particles grown in a columnar shape; a non-magnetic split layer 124 disposed on the magnetic recording layer 122 and containing Ru and oxygen; and an auxiliary recording layer 126 that is disposed on the split layer 124 and that is magnetically approximately continuous in an in-plane direction of a main surface of the base 110.
Owner:WESTERN DIGITAL TECH INC

Solid body surface evaluation method, magnetic disk evaluation method, magnetic disk, and manufacturing method thereof

In a method of evaluating surface tension of a solid body surface, selection is made of at least three liquid samples having different surface tensions, and contact angles between the respective liquid samples and the solid body surface are measured. Thereby, a correlation between cosines (Y) of the contact angles and surface tensions (X) of the liquid samples is derived as a logarithmic function. Surface tension of the solid body surface is evaluated by the use of a value of X that is calculated by substituting 1 for Y in the correlation. When evaluated by the foregoing evaluation method, a magnetic disk has a surface where the value of X, when 1 is substituted for Y, is greater than 0 and no greater than 17 mN / m.
Owner:WD MEDIA SINGAPORE PTE

Magnetic disk and method of producing the same

A magnetic disk includes a substrate on which a nonmagnetic metal layer, a magnetic layer, a carbon-based protection layer, an alcohol-based coupling layer, and a lubrication layer successively formed thereon. The lubrication layer contains a hydroxyl- or a carboxyl-modified compound as a lubricating material. The alcohol-based coupling layer contains, for example, lower alcohol as a main component and is deposited on the carbon-based protection layer, for example, by vapor deposition. The alcohol-based coupling layer may be replaced by a layer containing lower alcohol. The carbon-based protection layer may be deposited by plasma CVD.
Owner:WESTERN DIGITAL TECH INC

Magnetic disk and method of manufacturing same

Disclosed is a method of manufacturing magnetic disks, comprising a magnetic layer, a protective layer, and a lubricating layer on a substrate. In the process, a lubricant alpha comprising a compound denoted by chemical formulaHO—CH2—CH(OH)—CH2—O—CH2—CF2(—O—C2F4)p-(O—CF2)q-O—CF2—CH2—O—CH2—CH(OH)—CH2—OHwherein p and q are natural number,and a compound denoted by chemical formulaHO—CH2—CF2(—O—C2F4)m-(O—CF2)n-O—CF2—CH2—OHwherein m and n are natural number,is fractionated by molecular weight to prepare a lubricant a having a weight average molecular weight (Mw) of from 3,000 to 7,000 and a molecular weight dispersion of less than or equal to 1.2;a lubricant beta comprising a compound denoted by the chemical formulaHO—CH2—CF2(—O—C2F4)m-(O—CF2)n-O—CF2—CH2—OHwherein m and n are natural number,is fractionated by molecular weight to prepare a lubricant b having a weight average molecular weight (Mw) of from 2,000 to 5,000 and a molecular weight dispersion of less than or equal to 1.2;a lubricant c comprising a mixture of lubricants a and b is prepared; anda film of lubricant c is formed on a protective layer provided on a substrate to form a lubricating layer. A magnetic disk comprising a magnetic layer, a protective layer, and a lubricating layer on a substrate, in which the lubricating layer has been formed on the protective layer is also enclosed.
Owner:WD MEDIA SINGAPORE PTE

Lubricating compositions containing aromatized 1,2-dihydro-2,2,4-trimethylquinoline polymers

Lubricating compositions containing a major amount of a base oil and an effective amount of an additive component having at least one compound of formula (I):where R is one of the following radicals, methyl, ethyl, n-propyl, i-propyl or a combination thereof, and n=0-8. In a preferred embodiment, R is a methyl radical and n=2-3. The lubricating compositions provide improved lubricating performance, particularly by inhibiting oxidation and improving thermal stability.
Owner:VANDERBILT CHEM LLC

Magnetic recording medium

In a magnetic recording medium which comprises a substrate (1), a magnetic layer (3) formed on the substrate, a carbon-based protection layer (4) comprising carbon and formed on the magnetic layer, and a lubrication layer (5) formed on the carbon-based protection layer, the carbon-based protection layer comprises a hydrogenated carbon protection layer (4a) facing the magnetic layer and a nitrogenated carbon protection layer (4b) facing the lubrication layer. The hydrogenated carbon protection layer (4a) comprises carbon and hydrogen. The nitrogenated carbon protection layer (4b) includes no hydrogen but comprises carbon and nitrogen.
Owner:WD MEDIA SINGAPORE PTE

Magnetic disk and manufacturing method thereof

A magnetic disk is provided which is excellent in durability of the magnetic disk or particularly in LUL durability and CFT characteristics and has high reliability under a decreased floating amount of the magnetic head accompanying the recent rapid increase in a recording density and extremely severe environmental resistance accompanying diversification of the applications.The magnetic disk of the present invention is a magnetic disk having at least a magnetic layer, a carbon protective layer, and a lubrication layer sequentially provided on a substrate, and the lubrication layer is a film formed by a lubricant that contains two types of compounds having a perfluoropolyether main chain in the structure, a molecular weight distribution of the two types in total being within a range of 1 to 1.2, the two types of compounds including a compound a having a hydroxyl group at the end and a compound b having a number average molecular weight smaller than the number average molecular weight of the compound a and not more than 1500, and a content of the compound b in the two types of compounds being not more than 10%.
Owner:WESTERN DIGITAL TECH INC

Magnetic disk and method of manufacturing the same

Provided is a magnetic disk comprising a lubricating layer formed of a lubricant. The lubricant constituting the lubricating layer has excellent properties, for example, excellent fluidity, surface energy, and CFT properties. By virtue of the excellent properties, the magnetic disk has a high level of reliability despite a low flying height of a magnetic head due to a recent rapid increase in recording density and a very severe environment resistance requirement due to diversification of applications. The magnetic disk comprises a substrate and at least a magnetic layer, a protective layer, and a lubricating layer provided in that order over the substrate. The lubricating layer is formed of a lubricant that is a mixture of a specific perfluoropolyether lubricant with a lubricant formed of a compound comprising perfluoropolyether groups having a perfluoropolyether main chain in the structure thereof and having a hydroxyl group at the end thereof, the perfluoropolyether groups being bonded to each other through a divalent linking group having at least two hydroxyl groups in the structure thereof.
Owner:WESTERN DIGITAL TECH INC

Manufacturing method of magnetic recording medium

A manufacturing method of a magnetic recording medium provided with a protective layer excellent in corrosion resistance, mechanical durability, adhesion with a lubrication layer, and floating stability of a head even if the film thickness is reduced is provided. This is a manufacturing method of a magnetic recording medium in which at least a magnetic layer, a carbon protective layer, and a lubrication layer are sequentially provided on a substrate, and said carbon protective layer is provided with a lower layer formed on the magnetic layer side and an upper layer formed on the lubrication layer side. The lower layer is formed by a chemical vapor deposition (CVD) method using hydrocarbon gas and then, the upper layer is formed by using mixed gas of hydrocarbon gas and nitrogen gas and then, treatment which nitridizes the surface of the upper layer is applied.
Owner:WD MEDIA SINGAPORE PTE
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products