Patent classifications
G11B5/712
Magnetic recording medium, manufacturing method of particles of epsilon type iron oxide-based compound, and manufacturing method of magnetic recording medium
Provided are a magnetic recording medium including: a non-magnetic support; and a magnetic layer which is provided on at least one surface of the non-magnetic support and includes particles of epsilon type iron oxide-based compound, and a binding agent, in which a contact angle measured regarding a surface of the magnetic layer is equal to or greater than 30.0° and smaller than 45.0° with respect to 1-bromonaphthalene and 80.0° to 95.0° with respect to water, a manufacturing method of particles of an epsilon iron oxide-based compound, and a manufacturing method of a magnetic recording medium.
MAGNETIC TAPE CARTRIDGE AND MAGNETIC RECORDING AND REPRODUCING DEVICE
In the magnetic tape, a magnetic tape deformation amount after storage for 3 months each in a predetermined environment is 0.50 μm or less, a rate of a change in the magnetic tape deformation amount with respect to a change in relative humidity is 0.0001 μm/% to 0.0500 μm/%, and a rate of a change in magnetic tape deformation amount with respect to a change in temperature is 0.0010 μm/° C. to 0.1000 μm/° C.
MAGNETIC TAPE CARTRIDGE AND MAGNETIC RECORDING AND REPRODUCING DEVICE
In the magnetic tape, a magnetic tape deformation amount after storage for 3 months each in a predetermined environment is 0.50 μm or less, a rate of a change in the magnetic tape deformation amount with respect to a change in relative humidity is 0.0001 μm/% to 0.0500 μm/%, and a rate of a change in magnetic tape deformation amount with respect to a change in temperature is 0.0010 μm/° C. to 0.1000 μm/° C.
Magnetic recording medium and magnetic recording and reproducing device
The magnetic recording medium includes a non-magnetic support; and a magnetic layer including a ferromagnetic powder, in which the ferromagnetic powder is a ferromagnetic powder selected from the group consisting of a hexagonal strontium ferrite powder and an ε-iron oxide powder, the number of recesses having a depth which is ⅓ or more of a minimum recording bit length existing on a surface of the magnetic layer is less than 10/10,000 μm.sup.2, and a ratio d/t.sub.mag of a value d which is ⅓ of the minimum recording bit length to a thickness t.sub.mag of the magnetic layer is 0.15 to 0.50.
Magnetic recording medium and magnetic recording and reproducing device
The magnetic recording medium includes a non-magnetic support; and a magnetic layer including a ferromagnetic powder, in which the ferromagnetic powder is a ferromagnetic powder selected from the group consisting of a hexagonal strontium ferrite powder and an ε-iron oxide powder, the number of recesses having a depth which is ⅓ or more of a minimum recording bit length existing on a surface of the magnetic layer is less than 10/10,000 μm.sup.2, and a ratio d/t.sub.mag of a value d which is ⅓ of the minimum recording bit length to a thickness t.sub.mag of the magnetic layer is 0.15 to 0.50.
Magnetic recording medium having -iron oxide-containing particles
A magnetic recording medium, which is used in a recording and playback device in which the shortest recording wavelength is 75 nm or less, in which the magnetic recording medium has a recording layer including powder of ε-iron oxide-containing particles, the average particle size of the particles is 22 nm or less, the coercive force He is 220 kA/m or more and 320 kA/m or less, and the non linear transition shift is 20% or less.
Magnetic recording medium having -iron oxide-containing particles
A magnetic recording medium, which is used in a recording and playback device in which the shortest recording wavelength is 75 nm or less, in which the magnetic recording medium has a recording layer including powder of ε-iron oxide-containing particles, the average particle size of the particles is 22 nm or less, the coercive force He is 220 kA/m or more and 320 kA/m or less, and the non linear transition shift is 20% or less.
MAGNETIC TAPE AND MAGNETIC TAPE DEVICE
The magnetic tape includes a magnetic layer having ferromagnetic powder and a binder on a non-magnetic support, in which a total thickness of the magnetic tape is equal to or smaller than 5.30 μm, the magnetic layer includes a timing-based servo pattern, a center line average surface roughness Ra measured regarding a surface of the magnetic layer is equal to or smaller than 1.8 nm, one or more components selected from the group consisting of fatty acid and fatty acid amide are included in the magnetic layer, 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 the surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is equal to or greater than 45 atom %.
MAGNETIC TAPE AND MAGNETIC TAPE DEVICE
The magnetic tape includes a magnetic layer having ferromagnetic powder and a binder on a non-magnetic support, in which a total thickness of the magnetic tape is equal to or smaller than 5.30 μm, the magnetic layer includes a timing-based servo pattern, a center line average surface roughness Ra measured regarding a surface of the magnetic layer is equal to or smaller than 1.8 nm, one or more components selected from the group consisting of fatty acid and fatty acid amide are included in the magnetic layer, 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 the surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is equal to or greater than 45 atom %.
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.