Fujifilm Corporation

So Matsuyama

Norihito Kasada

Takuto Kurokawa

Yujin Shibata

Atsushi Musha

Wataru Kikuchi

Shota Kamimura

The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, in which an arithmetic average roughness Ra measured on a surface of the magnetic layer is 1.5 nm or less, and standard deviation σ of the Ra in a width direction of the surface of the magnetic layer is 0.20 nm or less.

Magnetic tape, magnetic tape cartridge, and magnetic tape apparatus

The magnetic tape includes a non-magnetic support, and a magnetic layer containing a ferromagnetic powder. In a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer with a scanning electron microscope at an acceleration voltage of 5 kV, the number of bright regions having an equivalent circle diameter of 75 nm or more and less than 125 nm is 100 or more and 4000 or less, and standard deviation σ of the number of the bright regions in a width direction of the surface of the magnetic layer is 400 or less.

Magnetic tape having characterized bright regions on magnetic layer, magnetic tape cartridge, and magnetic tape apparatus

The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, in which an AlFeSil abrasion value measured on a surface of the magnetic layer is 20 μm or more and 50 μm or less, and standard deviation a of the AlFeSil abrasion value obtained in a width direction of the surface of the magnetic layer is 5.0 μm or less.

Magnetic tape with characterized AlFeSil abrasion value, magnetic tape cartridge, and magnetic tape apparatus

The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, in which a contact angle with 1-bromonaphthalene, which is measured on a surface of the magnetic layer, is 45.0° or more and 55.0° or less, and standard deviation σ of the contact angle in a width direction of the surface of the magnetic layer is 1.0° or less.

The magnetic recording and reproducing device includes a magnetic recording medium, a recording element, and a reproducing element. The recording element is an inductive recording element having a first magnetic pole which generates a magnetic field, and a second magnetic pole which is spaced apart from the first magnetic pole with a write gap interposed therebetween, a tip width of the first magnetic pole is substantially the same as a tip width of the second magnetic pole, and a reproducing element width of the reproducing element is 0.2 μm or greater and less than 0.5 μm. In the magnetic recording medium, the number of recesses, which are present in a surface of the magnetic layer and have an equivalent circle diameter of 0.10 μm or greater and less than 0.20 μm, is 100 to 2,000 per area of 40 μm×40 μm.

Magnetic recording and reproducing device

The magnetic tape includes a non-magnetic support, and a magnetic layer containing a ferromagnetic powder, in which an edge portion Ra which is an arithmetic average roughness Ra measured at an edge portion of a surface of the magnetic layer is 1.50 nm or less, a central portion Ra which is an arithmetic average roughness Ra measured at a central portion of the surface of the magnetic layer is 0.30 nm to 1.30 nm, and a Ra ratio (central portion Ra/edge portion Ra) is 0.75 to 0.95.

Magnetic tape, magnetic tape cartridge, and magnetic tape device

In the magnetic recording and reproducing device, a distal end width of the first magnetic pole in the recording element is substantially the same as a distal end width of the second magnetic pole; the reproducing element width of the reproducing element is equal to or less than 0.8 &#x3bc;m; and in the magnetic recording medium, a number distribution A of equivalent circle diameters of a plurality of bright areas in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer with a scanning electron microscope at an acceleration voltage of 5 kV, and a number distribution B of equivalent circle diameters of a plurality of dark areas in a binarized image of a secondary electron image obtained by imaging the surface of the magnetic layer with a scanning electron microscope at an acceleration voltage of 2 kV satisfy predetermined number distribution, respectively.

The magnetic recording and reproducing device includes a magnetic recording medium, a recording element, and a reproducing element. The recording element is an inductive recording element having a first magnetic pole which generates a magnetic field, and a second magnetic pole which is spaced apart from the first magnetic pole with a write gap interposed therebetween, a tip width of the first magnetic pole is substantially the same as a tip width of the second magnetic pole, and a reproducing element width of the reproducing element is 0.5 &#x3bc;m to 0.8 &#x3bc;m. The magnetic recording medium has a non-magnetic support, and a magnetic layer containing a ferromagnetic powder, and the number of recesses, which are present in a surface of the magnetic layer and have an equivalent circle diameter of 0.20 &#x3bc;m to 0.50 &#x3bc;m, is 10 to 500 per area of 40 &#x3bc;m&#xd7;40 &#x3bc;m.

The magnetic recording medium includes: a non-magnetic support; and a magnetic layer including ferromagnetic powder, in which the magnetic layer includes a compound having a salt structure, and the salt structure is an ammonium salt structure of an alkyl ester anion represented by the following Formula 1. In Formula 1, R represents an alkyl group having 7 or more carbon atoms or a fluorinated alkyl group having 7 or more carbon atoms, Zrepresents an ammonium cation, and a water contact angle on a surface of the magnetic layer is 80&#xb0; or more and less than 100&#xb0;. A magnetic recording and reproducing apparatus includes the magnetic recording medium. 

Magnetic recording medium including compound having a salt structure and magnetic recording and reproducing apparatus

In the magnetic recording medium, a number distribution A of a plurality of bright regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 5 kV and a number distribution B of a plurality of dark regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 2 kV respectively satisfy a predetermined number distribution.

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Minami-ashigara, Japan

So Matsuyama