The present invention relates to a magnetic recording medium including a substrate; an underlayer laminated upon the substrate; and a magnetic layer laminated upon the underlayer, wherein the underlayer includes a first underlayer containing a compound represented by a following general formula: MgO.sub.(1-X), where X is within a range of 0.07 to 0.25, the magnetic layer includes a first magnetic layer containing an alloy having a L1.sub.0 structure, and the alloy having the L1.sub.0 structure includes B, and the first underlayer is in contact with the first magnetic layer.

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.

A magnetic recording medium according to one embodiment includes an underlayer and a magnetic layer above the underlayer. The magnetic layer includes a first magnetic material and particulates. A protective layer is positioned above the magnetic layer, the protective layer including a second material. A magnetic recording medium according to another embodiment includes a base film and a first nonmagnetic layer above the base film. The first nonmagnetic layer has first nonmagnetic particles. A second nonmagnetic layer is positioned above the first nonmagnetic layer, the second nonmagnetic layer having second nonmagnetic particles. A magnetic layer is positioned above the second nonmagnetic layer, the magnetic layer including a magnetic material.

Magnetic recording media including an interlayer configured to reduce lattice mismatch with adjacent layers of the media, such as an adjacent seed layer or an adjacent underlayer. In one example, an interlayer alloy is provided that includes tungsten (W) along with Cobalt (Co), Chromium (Cr), and Ruthenium (Ru). The atomic percentages of W and Ru within the interlayer are selected so that the amount lattice mismatch between the interlayer and its adjacent layers is below a preselected amount, such as below 3% as quantified by d-spacing. In some examples, the atomic percentage of Ru is greater than 25% and the atomic percentage of W is 2-10%. Methods of fabricating the magnetic recording media are also provided.

A magnetic tape device, in which a magnetic tape is caused to run between a winding reel and a cartridge reel in a state where a tension is applied in a longitudinal direction of the magnetic tape and a maximum value of the tension is 0.50 N or more, the magnetic tape after running in a state where the tension is applied is caused to be wound around the cartridge reel by applying a tension of 0.40 N or less in the longitudinal direction of the magnetic tape, and a cupping amount of the magnetic tape is in a range of ±2.0 mm.

A magnetic recording medium according to one embodiment includes an underlayer and a magnetic layer above the underlayer. The magnetic layer includes a first magnetic material and particulates. A solid protective layer is positioned above the magnetic layer, the protective layer including a second material. At least some of the particulates of the magnetic layer protrude completely through the protective layer. A method for forming a magnetic recording medium according to one embodiment includes forming a magnetic layer above a substrate, the magnetic layer including a first magnetic material and particulates, and forming a solid protective layer above the magnetic layer to a thickness whereby some of the particulates protrude through the protective layer and are exposed along an upper surface of the protective layer.

A method of manufacturing a magnetic recording medium forms an unfinished product including a magnetic recording layer and a protection layer that are successively formed on a substrate, and forms a lubricant layer on the protection layer of the unfinished product. The lubricant layer is formed by coating a first organic fluorine compound on the protection layer of the unfinished product, and supplying a gas, including a second organic fluorine compound, onto the protection layer of the unfinished product, and decomposing the second organic fluorine compound by Townsend discharge and ultraviolet ray irradiation. The protection layer includes carbon, and the first organic fluorine compound includes a functional group at a terminal thereof.

A magnetic recording tape having a plural-layer structure including at least a magnetic layer is provided. The tape has a total thickness of 5.6 μm or smaller, and includes a plurality of indentations disposed in a surface of the magnetic layer. A value obtained by dividing a depth D1 of each indentation with a thickness D2 of the magnetic layer is 15% or greater. The magnetic layer includes a plurality of indentations formed therein, a plurality of the indentations each has a depth of 20% or greater of the thickness of the magnetic layer, and the number of the indentations is 55 or more per 6,400 μm.sup.2 of a surface area of the magnetic layer.

The magnetic tape includes a non-magnetic support; and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, in which the magnetic layer has a servo pattern, and an absolute value ΔN of a difference between a refractive index Nxy measured regarding an in-plane direction of the magnetic layer and a refractive index Nz measured regarding a thickness direction of the magnetic layer is 0.25 to 0.40, a magnetic tape cartridge and a magnetic tape apparatus including this magnetic tape.

A magnetic recording medium according to one embodiment includes a base film and a first nonmagnetic layer above the base film. The first nonmagnetic layer has first nonmagnetic particles. A second nonmagnetic layer is positioned above the first nonmagnetic layer, the second nonmagnetic layer having second nonmagnetic particles. A magnetic layer is positioned above the second nonmagnetic layer, the magnetic layer including a magnetic material.