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.

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 comprising a soft magnetic undercoat film 2, an orientation control film 3, a perpendicular magnetization film 4, and a protective film 5, that are formed on a non-magnetic substrate 1, wherein the orientation control film 3 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 3 and &Dgr;&thgr;50 (mag) of the perpendicular magnetization film 4 is set within a range from 1 to 8 degrees.

Abstract: A magnetic recording medium that is capable of recording and reading back information at a higher density by improving the read/write characteristics and thermal stability, a method of manufacture therefor, and a magnetic read/write apparatus are provided. This magnetic recording medium, comprises an orientation control film that controls the orientation of a film provided directly thereabove, a perpendicular magnetic 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 the non-magnetic substrate, wherein the perpendicular magnetic film is made of a material which contains Co, Cr, Pt and Cu, the Cr content being 16 at % to 24 at % and the Cu content being 0.

Abstract: In a magnetic recording medium, a longitudinal hard magnetic layer, interlayer, longitudinal soft magnetic layer, and magnetic recording layer are multilayered on a substrate. The interlayer is one of a magnetic layer having saturation magnetization smaller than that of the longitudinal hard magnetic layer, a nonmagnetic layer mainly containing cobalt or ruthenium or having a thickness of 0.5 nm or less, and an oxide layer of the longitudinal hard magnetic layer.

Abstract: Epitaxial growth of a magnetic grain crystal in a perpendicular magnetic recording layer is interrupted.

Abstract: Disclosed is a magnetic recording medium having a laminate structure comprising at least a substrate, a Co alloy bias layer, a soft magnetic layer, and a magnetic recording layer. The direction of residual magnetization of the Co alloy bias layer faces one direction of its radial direction. Also, the perpendicular magnetic recording medium satisfies the relationship given below: Mssoft×(tsoft−40 nm)>Mssoft×40 nm+Msbias×tbias where, tbias denotes the thickness of the cobalt alloy bias layer, Msbias denotes the saturation magnetization of the cobalt alloy bias layer, tsoft denotes the thickness of the soft magnetic layer, which falls within a range of between 40 nm and 200 nm, and Mssoft denotes the saturation magnetization of the soft magnetic layer.

Abstract: A magnetic recording medium having excellent magnetic read/write characteristics and thermal stability characteristics, and a method of manufacturing therefor, and a magnetic read/write apparatus are provided. This magnetic recording medium comprises an orientation control film 3 that controls the orientation of a film provided directly thereabove, a perpendicular magnetic film 5, of which the axis of easy magnetization is generally oriented perpendicular to a substrate, and a protective film 6, that are provided on a non-magnetic substrate 1, wherein the orientation control film 3 is made of a non-magnetic material which contains 33 to 80 at % of Ni and one or more kinds of elements selected from Sc, Y, Ti, Zr, Hf, Nb and Ta.

Abstract: The present invention provides a magnetic recording medium that does not cause a deterioration of the noise characteristics and improves the production efficiency, a manufacturing method for the same, and a magnetic recording replay apparatus. An in-plane undercoat film 2 and an in-plane hard magnetic film 3 whose axis of easy magnetization is generally oriented in the in-plane direction are formed between the non-magnetic substrate 1 and the soft magnetic film 4, the in-plane undercoat film 2 comprises Cr or a Cr alloy, and the in-plane hard magnetic film 3 has as the major constituent a CoCrPtX alloy (where X is one or more of B, Ta, Cu, Zr, Nb, Re, Ni, Mn, Ge, Si, O, and N).

Abstract: Disclosed is a magnetic recording medium having a laminate structure comprising at least a substrate, a Co alloy bias layer, a soft magnetic layer, and a magnetic recording layer. The direction of residual magnetization of the Co alloy bias layer faces one direction of its radial direction.

Abstract: Disclosed is a perpendicular magnetic recording medium having magnetic characteristics by which an anisotropic magnetic field Hk and a saturation magnetization Ms satisfy the requirement 2<Hk/4&pgr;Ms<5, letting &agr; be the inclination of an MH loop when a magnetic field is applied perpendicularly, the anisotropic magnetic field Hk, the saturation magnetization Ms, and a coercive force Hc satisfy the requirement 0.01<{(&agr;−1)Hc+4&pgr;Ms}/Hk<0.2, and a longitudinal residual magnetization Mr is less than 0.2 times the saturation magnetization Ms.

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: 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: The present invention aims to provide a magnetic recording medium, a method for producing the same, and a magnetic recording and reproducing device which can prevent spike noise and improve the error rate.

Abstract: A perpendicular magnetic recording medium comprises a combination of an under layer of a laminate structure including at least two layers and a Co-based magnetic layer. The particular combination is selected from the group consisting of i) Fe-containing layer/Ru/magnetic layer, ii) Co-containing layer/Ru/magnetic layer, iii) Ru/Co-containing layer/magnetic layer, iv) Ti-containing layer/Ru/magnetic layer, and v) soft magnetic layer/V or Cr/magnetic layer. A multi-layered structure of magnetic layer/Ru/magnetic layer is used as the magnetic layer included in combinations i) to v) given above. The perpendicular magnetic recording medium of the particular construction permits improving the perpendicular orientation of the Co-based magnetic layer and exhibits a high coercive force and a high reproducing output.

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: 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: 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.

Abstract: According to this invention, there is provided a magnetic recording/reproducing system having a recording head for recording a signal in a magnetic recording medium along recording tracks having a predetermined track pitch and a reproducing head for reproducing the recorded signal. A relationship between a recording track width Tw of the recording head and a reproduction width Tr of the reproducing head is defined as Tr>Tw. When conditions g<(1500/Hc-Hc/4000.pi.+0.3)/(Hc/400.pi.-1/2) and g.gtoreq.(1500/Hc-Hc/4000.pi.+0.3-Tp+Tw)/(Hc/400.pi.-1/2) are satisfied, an erase region is formed between the recording tracks. In this case, the gap length of the recording head is represented by g [.mu.m], the recording track width is represented by Tw [.mu.m], the track pitch is represented by Tp [.mu.m], and the coercive force of the recording medium is represented by Hc [Oe].

Abstract: A magnetic recording medium comprising a substrate and a magnetic film formed on the substrate, the magnetic film including magnetic crystal grains in a non-magnetic matrix and satisfying the condition given below:d.sup.2 .multidot.t.multidot.Ir/(v.multidot.Isb).gtoreq.0.75wheret: a thickness of the magnetic film;Ir: a remanent magnetization moment of the magnetic film;d: an average particle size of the magnetic crystal grains in an intra-film direction of the magnetic film; andv.multidot.Isb: an activated magnetization moment of the magnetic film.

Abstract: A magnetic recording apparatus comprising a perpendicular recording medium, a recording head for perpendicular magnetization the perpendicular magnetization film of the recording medium, to thereby recording signals on the recording medium, and a reproducing head of magnetoresistance type for reading signals from the recording medium. The medium comprises a substrate, an underlayer formed on the substrate, and a perpendicular magnetization film formed on the substrate and having a crystal phase of a CoPt-based alloy and a compound phase of material selected from the group consisting of Co oxide, Co nitride and Co carbide.