Abstract: Disclosed is a perpendicular magnetic recording medium, comprising a nonmagnetic substrate, a longitudinal hard magnetic multi-layered film arranged on the nonmagnetic substrate, including a nonmagnetic intermediate layer and a pair of hard magnetic layers laminated one upon the other with the nonmagnetic intermediate layer interposed therebetween, and having at least two hard magnetic layers, a longitudinal soft magnetic layer formed on the longitudinal hard magnetic multi-layered film, and a perpendicular magnetic recording layer formed on the longitudinal soft magnetic layer. The perpendicular magnetic recording medium of the particular construction is capable of suppressing noise and achieves a high recording magnetic field intensity and a high recording resolution.

Abstract: An orientation control layer having a granular structure is formed between a substrate and magnetic recording layer, contains a base material and grains dispersed in the base material, and having a thickness smaller than a grain size of the grains.

Abstract: A multi-layer including a magnetic recording layer and a high-magnetostriction layer having a magnetostriction constant larger than that of the magnetic recording layer is formed.

Abstract: Disclosed is a perpendicular magnetic recording medium including a nonmagnetic substrate, a multilayered underlayer which includes a ferromagnetic underlayer having a perpendicular coercive force of 39.5 kA/m or less and a weakly magnetic underlayer having a saturation magnetization Ms of 50 to 150 emu/cc, and a perpendicular magnetic recording layer.

Abstract: A perpendicular magnetic recording medium comprising a layer exhibiting a super paramagnetism is used as the underlying film to enable the recording medium to achieve a high density recording with a low noise.

Abstract: Disclosed is a perpendicular magnetic recording medium in which an undercoating layer having crystal grains and a grain boundary material containing a carbide or boride is formed below a perpendicular magnetic recording layer, and another undercoating layer containing one of elements forming the crystal grains is formed below the aforementioned undercoating layer, and which can perform high□density recording by further decreasing the grain size of the perpendicular magnetic recording layer.

Abstract: A magnetic recording medium comprising: on a non-magnetic substrate, at least a soft magnetic undercoat film comprising a soft magnetic material; an orientation control film for controlling an orientation of a film directly above; a perpendicular magnetic film in which an axis of easy magnetization is oriented mainly perpendicularly with respect to the substrate; and a protection film, wherein the perpendicular magnetic film has a structure in which a large number of magnetic grains are separated by a grain boundary layer, and an average separating distance between the magnetic grains along a straight line which connects centers of gravity of mutually neighboring magnetic grains is 1 nm or greater.

Abstract: A perpendicular magnetic recording medium includes a magnetic recording layer stacked on a substrate and having a first perpendicular magnetic recording layer containing cobalt, and a second perpendicular magnetic recording layer mainly containing a crystalline alloy which contains a rare earth element and a transition metal.

Abstract: Magnetic recording media with thermal fluctuation resistance and low noise made compatible are obtained by using as magnetic layers a combination of a first magnetic material having a first Curie point higher than the recording temperature and a second magnetic material having a second Curie point higher than the operation temperature of the apparatus and lower than the recording temperature, a combination of a ferromagnetic material having a Curie point higher than the recording temperature and an antiferromagnetic material having a Neel point higher than the operation temperature of the apparatus and lower than the recording temperature.

Abstract: Disclosed is a perpendicular magnetic recording medium comprising a perpendicular magnetic layer formed at 280 to 450° C. by using a magnetic layer-forming material containing at least one additive component selected from the group consisting of cobalt, platinum, chromium, molybdenum and tungsten, the magnetic perpendicular layer being constructed to include a plurality of magnetic crystal grains separated from each other by crystal grain boundaries and providing the perpendicular magnetic layer in which the additive component is segregated in the crystal grain boundaries.

Abstract: A soft magnetic laminate layer is arranged between a nonmagnetic substrate and a perpendicular magnetic recording layer so as to provide a perpendicular magnetic recording medium low in noise and capable of a high density recording. The soft magnetic laminate layer comprises a soft magnetic layer having a thickness not larger than 500 Å and a nonmagnetic layer, comprises a first soft magnetic layer and a second soft magnetic layer differing from the first soft magnetic layer in the crystal structure, or comprises a layer of a granular structure consisting of magnetic particles and a nonmagnetic matrix and a soft magnetic layer.

Abstract: A soft magnetic laminate layer is arranged between a nonmagnetic substrate and a perpendicular magnetic recording layer so as to provide a perpendicular magnetic recording medium low in noise and capable of a high density recording. The soft magnetic laminate layer comprises a soft magnetic layer having a thickness not larger than 500 Å and a nonmagnetic layer, comprises a first soft magnetic layer and a second soft magnetic layer differing from the first soft magnetic layer in the crystal structure, or comprises a layer of a granular structure consisting of magnetic particles and a nonmagnetic matrix and a soft magnetic layer.

Abstract: This invention uses a perpendicular magnetic recording medium in which first and second magnetic recording layers are coupled by antimagnetic exchange coupling, or a longitudinal magnetic recording medium in which three or more predetermined interlayers are formed between first and second magnetic recording layers, and these layers are coupled by antimagnetic exchange coupling.

Abstract: A magnetic recording medium comprising: on a non-magnetic substrate, at least a soft magnetic undercoat film comprising a soft magnetic material; an orientation control film for controlling an orientation of a film directly above; a perpendicular magnetic film in which an axis of easy magnetization is oriented mainly perpendicularly with respect to the substrate; and a protection film, wherein the perpendicular magnetic film has a structure in which a large number of magnetic grains are separated by a grain boundary layer, and an average separating distance between the magnetic grains along a straight line which connects centers of gravity of mutually neighboring magnetic grains is 1 nm or greater.

Abstract: A medium having at least a nonmagnetic substrate, soft magnetic backing layer, soft magnetic underlayer, and perpendicular magnetic recording layer, and An oxidized layer of the soft magnetic backing layer is also formed on the soft magnetic backing layer, and the soft magnetic underlayer has a three-layered structure including a first soft magnetic layer, interlayer, and second soft magnetic layer, a crystalline orientation control layer, e.g., an Ni orientation control layer is formed between the soft magnetic underlayer and the perpendicular magnetic recording layer.

Abstract: The magnetic recording medium comprises a soft magnetic undercoat film, an orientation control film that controls the orientation of a film provided directly above, a perpendicular magnetic film of which axis of easy magnetization is generally oriented perpendicular to a non-magnetic substrate, and a protective film, that are provided on the non-magnetic substrate, wherein the orientation control film is made of a Co alloy which contains one or more elements selected from Ti, V, Sr, Y, Nb, Mo, Hf, Ta, Ni and W.

Abstract: The present invention provides a magnetic recording medium having excellent magnetic read/write characteristics and thermal stability, a method of manufacturing therefor, and a magnetic read/write apparatus. The magnetic recording medium comprises a soft magnetic undercoat film, an orientation control film, a perpendicular magnetization film, and a protective film, that are formed on a non-magnetic substrate, wherein the orientation control film has an hcp structure and, at the same time, &Dgr;&thgr;50 of the (0002) orientation plane is set within a range from 3 to 10 degrees and a difference (&Dgr;&thgr;50 (mag)−&Dgr;&thgr;50 (ori)) between &Dgr;&thgr;50 (ori) of the orientation control film and &Dgr;&thgr;50 (mag) of the perpendicular magnetization film is set within a range from 1 to 8 degrees.

Abstract: A magnetic recording medium comprising at least a soft magnetic layer, an orientation control film that controls the orientation of a film provided directly thereabove, an intermediate film, a perpendicular magnetic recording film of which the axis of easy magnetization is generally oriented perpendicular to a non-magnetic substrate, and a protective film, that are provided on said substrate, wherein the intermediate film has saturation magnetization Ms of at least 20 (emu/cc) and equal to or less than 200 (emu/cc), a method of manufacture thereof, and a magnetic read/write apparatus.

Abstract: A double layered perpendicular recording media having, between a soft magnetic layer and perpendicular magnetic recording layer, an alignment control layer containing an amorphous portion, a crystal size control layer, and an underlayer having one of a hexagonal closest packed structure and a face-centered cubic structure.

Abstract: By using a magnetic recording medium in which the value of Hk/4&pgr;Ms calculated from the anisotropic magnetic field Hk and the saturation magnetization Ms falls within a range of more than 2 and less than 5, the resistance to the thermal decay can be improved and a magnetic recording can be achieved with a high recording resolution and a good medium S/N without increasing the head magnetic field.