549results about "Protective coatings for layers" patented technology

A method of forming a discrete track recording pattern in a magnetic recording disk. In one embodiment, the discrete track recording pattern may be formed in a NiP layer continuous throughout the discrete track recording pattern. Alternatively, the discrete track recording pattern may be formed in a substrate.

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 %.

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.

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.

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.

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).

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°.

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.

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.

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.

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.

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.

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.

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%.

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.

A lubricant compound for a magnetic disk is provided which can realize further reduction of the magnetic spacing and moreover, has high reliability under a lower floating amount of the magnetic head involved with the recent rapid increase in the recording density and under extremely severe environmental resistance involved with diversification of the applications.

A lubricant compound is contained in a lubrication layer of a magnetic disk in which at least a magnetic layer, a protective layer, and a lubrication layer are sequentially provided on a substrate, and the lubricant compound contains a component A and a component B expressed by the following chemical formula:

[Chemical formula]1

Component A: X=OH

Component B: X=OCH₂CH(OH)CH₂OH

and a component C made of a specific compound having a phosphezene ring in the structure thereof.