Abstract: A magnetic-recording medium which is provided on a nonmagnetic substrate with at least an orientation-controlling layer for controlling the orientation of a layer formed directly thereon, a perpendicularly magnetic layer having an easily magnetizing axis oriented mainly perpendicularly relative to the nonmagnetic substrate, and a protective layer. The perpendicularly magnetic layer includes two or more magnetic layers, at least one of the magnetic layers is a layer having Co as a main component and containing Pt as well and containing an oxide, and at least another of the magnetic layers is a layer having Co as a main component and containing Cr as well and containing no oxide.

Abstract: A magnetic recording medium 62 wherein a substrate 11, undercoating layers 13 and 14 formed on the substrate 11, and a magnetic recording layer 15, which include the magnetic crystal grain and the grain boundary field which encloses magnetic crystal grains, are included. The grain boundary field includes Ti oxide, and the ratio of the substance amount of the Ti oxide in the magnetic recording layer 15 is 5 mol % or more and 15 mol % or less, and the Ti oxide includes at least TiO and/or Ti2O3s.

Abstract: To make possible high density recording by making the structure of the perpendicular magnetic recording layer finer. A perpendicular magnetic recording medium 10 includes at least a nonmagnetic under layer 2, a perpendicular magnetic layer 3, and a protective layer which are stacked on a nonmagnetic substrate 1, wherein the perpendicular magnetic layer includes ferromagnetic crystal grains and nonmagnetic crystal grain boundary regions, wherein the crystal grain boundary region includes at least two kinds of oxide.

Abstract: A magnetic-recording medium which is provided on a nonmagnetic substrate with at least an orientation-controlling layer for controlling the orientation of a layer formed directly thereon, a perpendicularly magnetic layer having an easily magnetizing axis oriented mainly perpendicularly relative to the nonmagnetic substrate, and a protective layer. The perpendicularly magnetic layer includes two or more magnetic layers, at least one of the magnetic layers is a layer having Co as a main component and containing Pt as well and containing an oxide, and at least another of the magnetic layers is a layer having Co as a main component and containing Cr as well and containing no oxide.

Abstract: A magnetic recording medium which is provided on a nonmagnetic substrate 1 with at least an orientation-controlling layer 3 for controlling the orientation of a layer formed directly thereon, a perpendicularly magnetic layer 4 having an easily magnetizing axis oriented mainly perpendicularly relative to the nonmagnetic substrate 1, and a protective layer 5 and characterized in that the perpendicularly magnetic layer 4 includes two or more magnetic layers, that at least one of the magnetic layers is a layer 4a having Co as a main component and containing Pt as well and containing an oxide and that at least another of the magnetic layers is a layer 4b having Co as a main component and containing Cr as well and containing no oxide.

Abstract: A soft magnetic undercoat film, a first undercoat film, a second undercoat film, a perpendicular magnetic recording film, and a protective film are provided on a non-magnetic substrate, and the first undercoat film consists of Pt, Pd, or an alloy including at least one among these, and the second undercoat film consists of Ru or an Ru alloy.

Abstract: Disclosed is a magnetic recording medium which includes a substrate, an underlayer, and a perpendicular magnetic recording layer, and in which this perpendicular magnetic recording layer contains magnetic crystal grains and a matrix surrounding the magnetic crystal grains, and the matrix contains an element selected from Zn, Cd, Al, Ga, and In, and a component selected from P, As, Sb, S, Se, and Te.

Abstract: The magnetic recording medium of the present invention has a substrate, a perpendicular magnetic recording layer, and a soft magnetic layer formed therebetween, having a thickness of less than 100 nm, the soft magnetic layer having a magnetic anisotropy in a surface direction, and product Bs·Hc, which is a production of a saturation magnetic flux density Bs and a coercive force Hc, of not less than 79 T·A/m (10 kG·Oe). By making the thickness of the soft magnetic layer into the above-mentioned range, the magnetic anisotropy in surface direction can be stabilized. magnetostatic energy can be increased sufficiently by making the Bs·Hc the above-mentioned range. Therefore, generating of the magnetic wall in the soft magnetic layer can be suppressed, the noise generating from the soft magnetic layer can be suppressed, and a high-density recording is enabled.

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 magnetic recording medium 62 wherein a substrate 11, undercoating layers 13 and 14 formed on the substrate 11, and a magnetic recording layer 15, which include the magnetic crystal grain and the grain boundary field which encloses magnetic crystal grains, are included. The grain boundary field includes Ti oxide, and the ratio of the substance amount of the Ti oxide in the magnetic recording layer 15 is 5 mol % or more and 15 mol % or less, and the Ti oxide includes at least TiO and/or Ti2O3s.

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. The present invention provides a magnetic recording medium, a method for producing the same, and a magnetic recording and reproducing device comprising at least one nonmagnetic substrate, a soft magnetic underlayer 2, an orientation control layer to control the orientation of the layer formed directly above the same, and a perpendicular magnetic layer having an axis of easy magnetization which is oriented mainly perpendicularly to the nonmagnetic substrate, and the soft magnetic underlayer 2 is formed with a multilayer structure having soft magnetic layers 21A and 21B, and one or more separation layers 22 interposed between the soft magnetic layers, and at least one of the soft magnetic layers 21A and 21B comprises a material with a structure having no magnetic domain walls.

Abstract: To provide a magnetic recording medium having a magnetic recording layer consisting of fine crystal grains with improved orientation. The soft magnetic layer 3, the seed layer 4, the under layer 5 and the magnetic recording layer 7 are formed successively on the non-magnetic substrate 1, wherein the seed layer 4 is made of a material containing Ni, the under layer 5 has a grain isolation type structure in which grains made of a non-magnetic material are isolated in a non-magnetic matrix and the non-magnetic matrix is made of a material containing Y2O3. With this constitution, the under layer 5 has improved characteristics in terms of uniformity of grains, sharpness of grain boundary, fineness of the grains and crystal orientation, and therefore the magnetic recording layer 7 that is formed on the under layer also has improved characteristics in terms of uniformity of grains, sharpness of grain boundary, fineness of the grains and crystal orientation.

Abstract: A perpendicular magnetic recording medium includes: a substrate; at least one underlayer formed above the substrate; and a perpendicular magnetic recording layer formed above the at least one underlayer, an easy magnetization axis of the perpendicular magnetic recording layer being oriented perpendicular to the substrate, the perpendicular magnetic recording layer including magnetic crystal particles and grain boundaries surrounding the magnetic crystal particles, wherein the grain boundaries contain an oxide of silicon and at least one element selected from the group consisting of Li, Na, K, Rb, Cs, Ca, Sr, and Ba, and the ratio of a total amount of substance of Si, Li, Na, K, Rb, Cs, Ca, Sr, and Ba in the perpendicular magnetic recording layer is no less than 1 mol % and no more than 20 mol %.

Abstract: To make possible high density recording by making the structure of the perpendicular magnetic recording layer finer. A perpendicular magnetic recording medium 10 includes at least a nonmagnetic under layer 2, a perpendicular magnetic layer 3, and a protective layer which are stacked on a nonmagnetic substrate 1, wherein the perpendicular magnetic layer includes ferromagnetic crystal grains and nonmagnetic crystal grain boundary regions, wherein the crystal grain boundary region includes at least two kinds of oxide.

Abstract: A magnetic recording medium, a method for producing the same, and a magnetic recording and reproducing device are provided which can prevent spike noise and improve the error rate. The magnetic recording medium comprises at least one nonmagnetic substrate, a soft magnetic underlayer, an orientation control layer to control the orientation of the layer formed directly above the same, and a perpendicular magnetic layer having an axis of easy magnetization which is oriented mainly perpendicularly to the nonmagnetic substrate. The soft magnetic underlayer is formed with a multilayer structure having at least two soft magnetic layers and one or more separation layers interposed between the soft magnetic layers, and at least one of the soft magnetic layers comprises a material with a structure having no magnetic domain walls.

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: A magnetic recording medium includes a nonmagnetic substrate on which is provided at least a soft magnetic under-film, an orientation control film that controls an orientation of a film directly above, a perpendicular magnetic recording film having an axis of easy magnetization oriented to be mainly perpendicular to the substrate and a protective film, wherein the orientation control film is alloy containing at least Cr and C. The magnetic recording medium is manufactured by a method including carrying out, in order, at least a step of forming a soft magnetic under-film on a nonmagnetic substrate, a step of forming an orientation control film that controls an orientation of a film directly above, a step of forming a perpendicular magnetic recording film having an axis of easy magnetization oriented to be mainly perpendicular to the substrate, and a step of forming a protective film.

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 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: A magnetic recording medium which is provided on a nonmagnetic substrate 1 with at least an orientation-controlling layer 3 for controlling the orientation of a layer formed directly thereon, a perpendicularly magnetic layer 4 having an easily magnetizing axis oriented mainly perpendicularly relative to the nonmagnetic substrate 1, and a protective layer 5 and characterized in that the perpendicularly magnetic layer 4 includes two or more magnetic layers, that at least one of the magnetic layers is a layer 4a having Co as a main component and containing Pt as well and containing an oxide and that at least another of the magnetic layers is a layer 4b having Co as a main component and containing Cr as well and containing no oxide.