G11B5/70

Single reel magnetic tape cartridge with predefined servo band interval difference

Provided is a magnetic tape cartridge of a single reel type in which a magnetic tape is wound around a reel, in which the magnetic tape includes a non-magnetic support and a magnetic layer containing a ferromagnetic powder, and has a tape thickness of 5.3 μm or less, the magnetic layer includes a plurality of servo bands, and a difference (G.sub.inner−G.sub.outer) between a servo band interval G.sub.inner in a range of 49 m to 51 m from a tape inner end and a servo band interval G.sub.outer in a range of 49 m to 51 m from a tape outer end is −3.9 μm to −1.1 μm as a value measured on 100th day from a date of magnetic tape cartridge manufacture.

Magnetic tape having characterized coefficient of variation of e-iron oxide powder particle size, magnetic tape cartridge, and magnetic recording and reproducing apparatus

The magnetic tape includes a non-magnetic support and a magnetic layer including ferromagnetic powder, in which the ferromagnetic powder is ε-iron oxide powder, and a coefficient of variation of particle size of the ε-iron oxide powder in a longitudinal direction of the magnetic layer is 0.50% or more and 5.00% or less.

MAGNETIC TAPE AND MAGNETIC TAPE DEVICE

The magnetic tape has a magnetic layer containing ferromagnetic powder and binder on a nonmagnetic support, wherein a timing based servo pattern is present on the magnetic layer, the centerline average surface roughness Ra that is measured on the surface of the magnetic layer is less than or equal to 1.8 nm, and the coefficient of friction that is measured on the base portion of the surface of the magnetic layer is less than or equal to 0.35.

MAGNETIC TAPE

The magnetic tape has a magnetic layer containing ferromagnetic powder and binder on one surface of a nonmagnetic support and has a backcoat layer containing nonmagnetic powder and binder on the other surface thereof, wherein the thickness of the backcoat layer is less than or equal to 0.20 μm, and the contact angle for 1-bromonaphthalene that is measured on the surface of the backcoat layer falls within a range of 10.0° to 30.0°.

Magnetic recording medium

A magnetic recording medium includes a nonmagnetic support body, and a magnetic layer containing magnetic powder, in which the magnetic powder contains ε-Fe.sub.2O.sub.3 crystal (including a case of substituting a portion of Fe site with a metal element M), a product of residual magnetization and a thickness of the magnetic layer is from 0.5 mA to 6.0 mA, and a squareness ratio which is measured in a longitudinal direction of the magnetic layer is 0.3 or less.

Magnetic recording medium

A magnetic recording medium includes a nonmagnetic support body, and a magnetic layer containing magnetic powder, in which the magnetic powder contains ε-Fe.sub.2O.sub.3 crystal (including a case of substituting a portion of Fe site with a metal element M), a product of residual magnetization and a thickness of the magnetic layer is from 0.5 mA to 6.0 mA, and a squareness ratio which is measured in a longitudinal direction of the magnetic layer is 0.3 or less.

Magnetic tape, magnetic tape cartridge, and magnetic tape apparatus
11430478 · 2022-08-30 · ·

Provided are a magnetic tape including: 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 an isoelectric point of a surface zeta potential of the magnetic layer is equal to or greater than 5.5, and an isoelectric point of a surface zeta potential of the back coating layer is equal to or greater than 4.5, a magnetic tape cartridge, and a magnetic tape apparatus including this magnetic tape.

Magnetic tape, magnetic tape cartridge, and magnetic tape apparatus

The magnetic tape includes a non-magnetic support and a magnetic layer including ferromagnetic powder and a binding agent, in which the magnetic layer has a timing-based servo pattern, an edge shape of the timing-based servo pattern, specified by magnetic force microscopy is a shape in which a difference (L.sub.99.9−L.sub.0.1) between a value L.sub.99.9 of a cumulative distribution function of 99.9% and a value L.sub.0.1 of a cumulative distribution function of 0.1% in a position deviation width from an ideal shape of the magnetic tape in a longitudinal direction is 180 nm or less, and an isoelectric point of a surface zeta potential of the magnetic layer is 3.8 or less.

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.

MAGNETIC TAPE AND METHOD OF MANUFACTURING THE SAME

The magnetic tape has a magnetic layer and a backcoat layer, wherein the Ra on the magnetic layer side surface is less than or equal to 1.8 nm, the coefficient of friction measured on the base portion of the magnetic layer side surface is less than or equal to 0.35, the Ra measured on the backcoat layer side surface is less than or equal to 5.0 nm, the backcoat layer contains a fatty acid ester, the FWHM.sub.before measured on the backcoat layer side surface before vacuum heating is greater than 0 nm but less than or equal to 10.0 nm, the FWHM.sub.after after vacuum heating is greater than 0 nm but less than or equal to 10.0 nm, and the difference between the spacing measured on the backcoat layer side surface after and before vacuum heating is greater than 0 nm but less than or equal to 8.0 nm.