Patent classifications
G11B5/8404
MAGNETIC TAPE
Provided is a magnetic tape in which ferromagnetic powder included in a magnetic layer is ferromagnetic hexagonal ferrite powder having an activation volume equal to or smaller than 1,600 nm.sup.3, the magnetic layer includes one or more components selected from the group consisting of fatty acid and fatty acid amide, and an abrasive, 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 magnetic layer at a photoelectron take-off angle of 10 degrees is equal to or greater than 45 atom %, and a tilt cos θ of the ferromagnetic hexagonal ferrite powder with respect to the surface of the magnetic layer acquired by cross section observation performed by using a scanning transmission electron microscope is 0.85 to 1.00.
MAGNETIC RECORDING MEDIUM AND MAGNETIC MEMORY DEVICE
A magnetic recording medium includes a substrate; a lower base layer formed on the substrate; and a (001) oriented L1.sub.0 magnetic layer formed on the lower base layer and including a first magnetic layer formed on the lower base layer and having a granular structure of magnetic grains and a grain boundary portion, the grain boundary portion containing C, and a second magnetic layer formed on the first magnetic layer and having a granular structure of magnetic grains and a grain boundary portion, the grain boundary portion containing oxide or nitride, the second magnetic layer further containing one or more elements selected from a group consisting of Mg, Ni, Zn, Ge, Pd, Sn, Ag, Re, Au and Pb as an additive.
GLASS FOR MAGNETIC RECORDING MEDIUM SUBSTRATE OR FOR GLASS SPACER TO BE USED IN MAGNETIC RECORDING/REPRODUCING DEVICE, MAGNETIC RECORDING MEDIUM SUBSTRATE, MAGNETIC RECORDING MEDIUM, GLASS SPACER TO BE USED IN MAGNETIC RECORDING/REPRODUCING DEVICE, AND MAGNETIC RECORDING/REPRODUCING DEVICE
Provided is a glass for a magnetic recording medium substrate or for a glass spacer for a magnetic recording/reproducing apparatus, in which the total content of Li.sub.2O, Na.sub.2O, K.sub.2O, B.sub.2O.sub.3, and ZnO (Li.sub.2O+Na.sub.2O+K.sub.2O+B.sub.2O.sub.3+ZnO) is in a range of 0 mol % or more and 3 mol % or less, the mole ratio of the total content of Al.sub.2O.sub.3 and MgO relative to the total content of SiO.sub.2 and CaO [(Al.sub.2O.sub.3+MgO)/(SiO.sub.2+CaO)] is in a range of 0.30 or more and 0.6 or less, the total content of SiO.sub.2 and Al.sub.2O.sub.3 (SiO.sub.2+Al.sub.2O.sub.3) is in a range of 64 mol % or more and 85 mol % or less, and the total content of SiO.sub.2, Al.sub.2O.sub.3, MgO, and CaO (SiO.sub.2+Al.sub.2O.sub.3+MgO+CaO) is in a range of 87 mol % or more and 98 mol % or less.
Magnetic-disk substrate, magnetic disk, and magnetic-disk drive device
A magnetic-disk substrate has a pair of main surfaces, and an arithmetic average roughness Ra of each of the main surfaces is 0.11 nm or less. The arithmetic average roughness Ra is a value obtained through measurement using an atomic force microscope provided with a probe having a probe tip provided with a carbon nanofiber rod-shaped member. The magnetic-disk substrate is made of glass or aluminum alloy.
Polishing liquid, method for manufacturing glass substrate, and method for manufacturing magnetic disk
Letting a particle diameter be Dx (μm) when a cumulative particle volume cumulated from the small particle diameter side reaches x (%) of the total particle volume in a particle size distribution obtained regarding cerium oxide included in a polishing liquid using a laser diffraction/scattering method, D5 is 1 μm or less, and a difference between D95 and D5 is 3 μm or more.
DUMMY SUBSTRATE AND MANUFACTURING METHOD THEREOF CROSS-REFERENCE TO RELATED APPLICATION
A dummy substrate is formed with a disk-shaped glass substrate having a center hole, and a magnetic recording film on an outer circumferential surface along a thickness direction of the glass substrate and an inner circumferential surface of the center hole, and a surface roughness (Ra) of one surface and the other surface of the glass substrate is in a range of 0.2 nm or more and 100 nm or less.
Fabrication methods for magnetic recording tape having resilient substrate
A method for making a magnetic recording tape, in accordance with one approach, includes coupling an underlayer to a substrate, the substrate comprising a poly ether ether ketone (PEEK). A method for making a magnetic recording tape in accordance with another approach includes coupling an underlayer to a substrate via radiation-induced grafting, the substrate comprising a poly ether ether ketone (PEEK). A recording layer may be coupled to the underlayer.
Protective layer for mitigating protruding defects in magnetic tape recording media
A method for forming a magnetic recording medium according to one embodiment includes forming a magnetic layer above an underlayer. The magnetic layer includes a first magnetic material and particulates. A protective layer is formed above the magnetic layer, the protective layer including a second material. A method for forming a magnetic recording medium according to another embodiment includes forming a first nonmagnetic layer above a base film. The first nonmagnetic layer has first nonmagnetic particles. A second nonmagnetic layer is formed above the first nonmagnetic layer, the second nonmagnetic layer having second nonmagnetic particles. A magnetic layer is formed above the second nonmagnetic layer, the magnetic layer including a magnetic material.
Writer pole formation
Implementations disclosed herein provide a method of reducing the topography at the alignment and overlay marks area during the writer pole photolithography process in order to reduce the wafer scale variation and reduce the writer pole photolithography process rework rate. In one implementation, an intermediate stage of a wafer for writer pole formation is generated by removing a part of at least one metallic writer pole layer on top of an intermediate stage writer pole wafer to form a recovery trench, depositing an optically transparent material on top of the wafer, wherein the thickness of the optically transparent material is higher than a target recovery trench topography, forming a photoresist pattern on top of the optically transparent material over the recovery trench, etching the optically transparent material, and removing the photoresist pattern and at least part of the remaining optically transparent material.
Processing machine of display apparatus and processing method of glass substrate
The present invention discloses a processing machine of a display apparatus, the processing machine comprises: a metal support plate; a plurality of support structures, which is movably disposed on the support plate, is used for supporting on the non-display region of the glass substrate, wherein the position of which the support structure is disposed on the metal support plate is corresponded to the position of the non-display region in the panel of the glass substrate, in order to make the support structure placed on the non-display region. The present invention also discloses a processing method of a glass substrate. Through the above way, the present invention can avoid the support structure placed on the display region of the glass substrate, effectively preventing the phenomenon of the brightness uneven.