Abstract: A perpendicular magnetic recording medium is disclosed that includes a substrate, an underlayer formed of one of Ru and a Ru alloy on the substrate, and a recording layer formed on the underlayer. The underlayer includes multiple crystal grains extending in a direction perpendicular to the surface of the substrate, the crystal grains being separated from each other by a first air gap part. The recording layer includes multiple magnetic particles deposited on the crystal grains of the underlayer, the magnetic particles being separated from each other by a second air gap part.

Abstract: A magnetic recording medium exhibiting low noise and having a sufficiently high coercive force includes a magnetic layer having a granular structure including ferromagnetic crystal grains with a hexagonal closed packed structure and a nonmagnetic grain boundary region of mainly an oxide intervening between the crystal grains. An underlayer has a body-centered cubic lattice structure. A nonmagnetic intermediate layer with the hexagonal closest packed structure includes Ru, Os, and/or Re, which are provided between the magnetic layer and the underlayer. A degree of mismatching ?=|d1?d2|/d1 is at most 10%, for instance, in a range from 2.5% to 7.0%, where d1 is a spacing of lattice planes of the crystal grains in the magnetic layer and d2 is a spacing of the lattice planes of the crystal grains in the intermediate layer.

Abstract: A perpendicular magnetic recording medium including an interlayer structure for crystallographically orienting a layer of a hexagonal close-packed (hcp) perpendicular magnetic recording material formed thereon, comprising in overlying sequence from a surface of a magnetically soft underlayer: (1) a first crystalline layer of a material having a first lattice parameter and a strong preferred growth orientation; (2) a second crystalline layer of a material having a second lattice parameter and the same strong preferred growth orientation as the first crystalline layer; and (3) a third crystalline layer of an hcp material, having a [0002] lattice parameter similar to or different from that of the second lattice parameter of the second crystalline layer and a strong <0002> preferred growth orientation, wherein: the second crystalline layer has a lower interfacial energy with the first crystalline layer and a higher interfacial energy with the third crystalline layer, owing to a lower surface energy of th

Abstract: A multiple layer structure comprising a pair of spaced-apart crystalline layers of different materials with an intermediate crystalline layer between and in contact with each of the pair of crystalline layers, the intermediate crystalline layer providing one of the crystalline layers of the pair with a stronger out-of-plane preferred growth orientation than if each of the pair of crystalline layers are in overlying contact. Disclosed and preferred embodiments include perpendicular magnetic recording media comprising the multiple layer structure as an intermediate layer structure beneath a perpendicular magnetic recording layer for strengthening a preferred out-of-plane growth orientation of the latter.

Abstract: A perpendicular magnetic recording medium includes a substrate, an underlayer formed on the substrate, and containing at least one element selected from the group A consisting of Pt, Pd, Rh, Ag, Au, Ir and Fe, and at least one element or compound selected from the group B consisting of C, Ta, Mo, W, Nb, Zr, Hf, V, Mg, Al, Zn, Sn, In, Bi, Pb, Cd, SiO2, MgO, Al2O3, TaC, TiC, TaN, TiN, B2O3, ZrO2, In2O3 and SnO2, and a magnetic layer formed on the underlayer, containing at least one element selected from the group consisting of Fe, Co, and Ni, and at least one element selected from the group consisting of Pt, Pd, Au and Ir, and containing crystal grains having an L10 structure.

Abstract: The invention provides a magnetic recording medium and a method of manufacturing the magnetic recording medium, in which a high density and good storage stability can be achieved by giving anisotropy in shape to a magnetic substance. A plan shape of the magnetic substance in the magnetic recording medium, which appears on the recording surface side, is an ellipse that is present within a rectangle and has a minor axis with a length equal to a short side of the rectangle. A quadrilateral defined by four intersects of two adjacent vertical rows and two adjacent horizontal rows, each of these rows comprising a plurality of pores, has a rectangular or rhombic shape.

Abstract: A nonmagnetic foundation layer is made to have a body-centered cubic crystal structure with a preferred crystal orientation plane being the bcc (110) plane. A nonmagnetic intermediate layer, provided between the foundation layer and a granular magnetic layer, has a hexagonal close-packed structure with the hcp (100) plane or the hcp (200) plane being the preferred orientation plane. Furthermore, the crystal lattice misfit amount between the nonmagnetic intermediate layer 3 and the granular magnetic layer is made to be not more than 10% for each of an a-axis and a c-axis. As a result, epitaxial growth of ferromagnetic crystals in the granular magnetic layer, which has an hcp structure, is promoted, and hence the crystallinity of the magnetic layer is increased, and thus it becomes possible to simultaneously realize an increase in coercivity and a reduction in noise. Depositing the layers on an unheated substrate yields reduces manufacturing costs.

Abstract: A magnetic recording medium for perpendicular magnetic recording system includes a nonmagnetic substrate and layers sequentially laminated on the substrate. The layers include a seed layer comprised of a metal or an alloy with a face centered cubic crystal structure, a nonmagnetic underlayer of a metal or an alloy with a hexagonal closest packed crystal structure, a magnetic layer having a granular structure including ferromagnetic crystalline grains with a hexagonal closest packed structure and nonmagnetic grain boundary region of mainly oxide surrounding the crystalline grains, a protective layer, and a liquid lubricant layer.

Abstract: A magnetic recording medium constructed in accordance with the invention comprises a substrate, first, second and third underlayers formed over the substrate, and a magnetic data recording layer formed over the underlayers. The underlayers typically have a bcc crystal structure, and comprise Cr or Cr alloys. The magnetic data recording layer has a hcp crystal structure and comprises a Co alloy. The second underlayer typically comprises a material such as B, which tends to reduce the crystal size of the second underlayer and the layers deposited thereon, and also to increase crystal spacing.

Abstract: The quantity of oxide contained in a magnetic layer is controlled to control the crystal grains and the segregation structure for ensuring low noise characteristic in a granular magnetic layer of a perpendicular magnetic recording medium. The granular magnetic layer consists of ferromagnetic crystal grains and a nonmagnetic grain boundary region mainly of an oxide surrounding the ferromagnetic crystal grains. The perpendicular magnetic recording medium has a nonmagnetic underlayer composed of a metal or alloy having hexagonal closest-packed crystal structure. The ferromagnetic crystal grain is composed of an alloy containing at least cobalt and platinum. The volume proportion of the nonmagnetic grain boundary region mainly of the oxide falls within a range of 15% to 40% of the volume of the total magnetic layer.

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 double layer perpendicular magnetic recording medium having a high medium S/N ratio at a recording density of 50 Gb/in2 or higher and a magnetic storage apparatus with a lower error rate and excellent reliability are provided. In a perpendicular magnetic recording medium in which a soft magnetic underlayer 12, an intermediate layer 13, and a perpendicular magnetic recording layer 14 are sequentially formed on a substrate 11, the intermediate layer 13 is made to be a non-magnetic amorphous alloy, in which Ni is a main component and Zr is contained, and the soft magnetic underlayer 12 is constituted of ferromagnetic nan-crystals precipitated by annealing.

Abstract: A magnetic recording medium includes an underlayer formed on a substrate and a magnetic layer formed by epitaxial growth on the underlayer. The underlayer is made of Cr based substance, and the magnetic layer is made of Co based magnetic substance. The magnetic layer further includes a plurality of layers, each made of Co based alloy including at least one of oxide and nitride as additional content.

Abstract: A thin film magnetic structure, magnetic devices, and method of producing the same, wherein (110) textured, symmetry broken body centered cubic or body centered cubic derivative crystalline structures epitaxially grown on hexagonal shaped templates, in the presence of a symmetry breaking mechanism is provided to promote oriented uniaxial magnetic properties from a series of successively deposited film layers, result in new oriented magnetic layer structures and microstructures and thus improved magnetic devices and device performance.

Abstract: A magnetic recording medium which comprises a substrate, an orientation control layer formed directly thereon, and a Co alloy magnetic layer formed thereon directly or indirectly with a Cr underlayer or Cr alloy underlayer interposed between them, the orientation control layer having an L10 crystal structure, L21 crystal structure, fcc crystal structure, or B2 (CsCl) crystal structure containing B, owing to this construction, has a high coercive force and a low noise level and is only slightly vulnerable to thermal fluctuation.

Abstract: A magnetic recording medium including a textured surface that is textured in a predetermined direction. The textured surface preferably has a distance ? between two mutually adjacent texturing lines satisfying a relationship 5<?<30 nm, and an angle ? between the textured surface and an oblique texture plane satisfying a relationship 0.5<?<7 degrees. There is also a Cr-based underlayer provided on the textured surface that has a preferred growth so that a number of grains having Cr<110> in a vicinity of 0 degrees or 90 degrees with respect to the predetermined direction is two times or greater than a number of grains having Cr<110> in a vicinity of 45 degrees with respect to the predetermined direction. Additionally, there is also a Co-based magnetic layer provided on the underlayer that has Co(1120) preferred growth along the predetermined direction.

Abstract: A magnetic recording medium is disclosed that includes a substrate; an anodic alumina film formed on the substrate; a pore formed in the anodic alumina film; a carbon layer covering the surface of the anodic alumina film and the inner wall of the pore; a magnetic particle formed on the carbon layer inside the pore; and a lubrication layer covering the carbon layer and the magnetic particle.

Abstract: Provided is a perpendicular magnetic recording medium including a perpendicular magnetic enhancement layer having a thickness of 15 nm or greater between a substrate and a perpendicular magnetic recording layer.

Abstract: A magnetic recording and reproduction method comprising recording or reproducing a track of a rotating magnetic disk by means of a magnetic head, wherein the magnetic disk comprises a support and a magnetic layer containing ferromagnetic powder and a binder; the track has a breadth of 2 ?m or less; and a frictional force between the magnetic layer and the magnetic head at innermost peripheral area of a recording region of the magnetic disk is 30 mN or less, a frictional force between the magnetic layer and a magnetic head at outermost peripheral area of a recording region of the magnetic disk is 20 mN or less, and a ratio of the frictional force at the innermost peripheral area to the frictional force at the outermost peripheral area is from 1.0 to 4.0.

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 has a material composition forming a C11b structure. 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: A magnetic recording medium including a substrate, a first seed layer provided on the substrate, a second seed layer provided on the first seed layer and formed of the same material as that of the first seed layer, and a plurality of crystal layers provided on the second seed layer and including a magnetic recording layer. A normal to a crystal lattice plane preferentially oriented in a given direction in each grain composing one of the first and second seed layers is inclined from a normal to the upper surface of the substrate.

Abstract: A perpendicular magnetic recording medium has a granular magnetic layer and a nonmagnetic underlayer of a metal or an alloy having a hexagonal close packed (hcp) crystal structure. A seed layer of a metal or an alloy of a face-centered cubic (fcc) crystal structure is provided under the nonmagnetic underlayer. Such a perpendicular magnetic recording medium exhibits excellent magnetic characteristics even when the thickness of the underlayer or the total thickness of the underlayer and the seed layer is very thin. Excellent magnetic characteristics can be obtained even when of the substrate is not preheated. Accordingly, a nonmagnetic substrate, such as a plastic resin can be employed to reduce the manufacturing cost.

Abstract: A perpendicular recording medium includes a perpendicular recording layer formed over a substrate through a soft magnetic underlayer, the soft magnetic underlayer then being arranged to include a plurality of soft magnetic layers physically separated by a non-magnetic layer, and further, the soft magnetic layers being formed of nanocrystals, with these arrangements, local magnetic loops are formed between the soft magnetic layers that are adjacent to each other through the non-magnetic layer, thereby suppressing spike noise and modulation that arises from the soft magnetic underlayer.

Abstract: A method of manufacturing a perpendicular magnetic recording medium, comprises steps of: (a) providing a substrate of an amorphous thermoplastic polymer material having softening and glass transition temperatures as low as about 95° C.; and (b) forming at least one stack of thin film layers atop at least one surface of the substrate, the at least one layer stack including at least one granular magnetic recording layer of perpendicular type, wherein oxides and/or nitrides provide physical de-coupling of adjacent magnetic grains; and wherein each of the thin film layers is formed by depositing at a substrate temperature not greater than about 70° C., and the coercivity (Hc) of the resultant perpendicular magnetic recording medium is at least about 4,000 Oe.

Abstract: The present invention provides a polyester film particularly useful as a base film for a magnetic recording medium such as cassette-type magnetic tape of a digital recording mode and a production process thereof. The polyester film is produced by irradiating UV light onto a surface of a film in a non-stretched stage or a stage prior to the completion of stretching to form fine protrusions on the surface. The fine protrusions on the film surface are specified by the ratio of 10-point average roughness Rz to center line average roughness Ra (Rz/Ra) on the surface (less than 20), the difference in concentration of carboxyl groups between the surface layer part and the inside of the film, and the number of fine protrusions.

Abstract: The longitudinal magnetic recording medium includes a non-magnetic substrate, a first underlayer having at least one of an amorphous structure and a fine crystal structure formed on the non-magnetic substrate, a second underlayer having a body-centered cubic structure formed on the first underlayer, a third underlayer having a hexagonal closed packed structure formed on the second underlayer, and a magnetic layer having the hexagonal closed packed structure formed on the third underlayer, wherein the third underlayer is composed of an alloy containing Co and Ru.

Abstract: A magnetic recording medium and a manufacturing method therefore includes a protective film, a nonmagnetic substrate, a nonmagnetic base layer, a nonmagnetic intermediate layer, a magnetic layer, and a liquid lubricant layer. The nonmagnetic base layer has a body-centered cubic structure and a (200) plane including a crystal-orientation parallel with a surface of the protective film. The nonmagnetic intermediate layer has a hexagonal close-packed structure and a (110) plane including a crystal-orientation parallel with the surface of the protective film. The magnetic layer has a granular structure including hexagonal close-packed ferromagnetic crystal grains and oxide-based nonmagnetic grain boundaries surrounding the ferromagnetic crystal grains. The nonmagnetic base layer, the nonmagnetic intermediate layer, the magnetic layer, the protective film, and the liquid lubricant layer are sequentially stacked on the nonmagnetic substrate.