Abstract: An information recording layer consisting of a composite of an ordered alloy of L10 crystal structure selected from a group A, and MgO is used for a perpendicular magnetic recording medium. The group A includes an FePt ordered alloy, a CoPt ordered alloy, an FePd ordered alloy and an alloy thereof. This information recording layer has a very small magnetic domain structure and allows high density recording as seen from a signal output spectrum showing a result of a recording and reproducing evaluation of a magnetic recording medium in one example. The information recording layer can be formed at lower film formation temperature than a temperature of a composite thin film of an ordered alloy of L10 crystal structure according to a conventional technique.

Abstract: Disclosed is a process for preparation of crystallized glass obtained by making a glass containing TiO2 subjected to a phase separation step and a crystallization step, where the phase separation step has heat treatment of the glass at a temperature in a range from a temperature of the glass transition temperature Tg (Tg−30° C.) to a temperature 60° C. higher than the glass transition temperature Tg (Tg+60° C.). There are also disclosed a crystallized glass for information recording disk composed of the crystallized glass obtained by the preparation process, where a mean particle size of the crystal particles is in a range of equal to or less than 100 nm, or where a transparency at a wavelength of 600 nm is 40% or higher; and an information recording disk, composed of the glass, having a polished surface with a surface roughness Ra (JIS B0601) in a range from 0.1 to 0.5 nm.

Abstract: A flexible magnetic layer based rubberized mat of extensive area for temporarily protecting the metal roof or a metal floor of a vehicle carrying luggage and the like.

Abstract: A production process for an oxide magnetic material comprising the steps of blending raw material powder so as to take the composition of a hexagonal ferrite including: at least one kind of an element A selected from the group consisting of Ba, Sr and Ca; Co and Cu; Fe; and O; and sintering said blended powder at a temperature lower than 1000° C.

Abstract: The present invention provides a longitudinal magnetic recording media having a substrate, a Co or Co alloy based magnetic layer arid an underlayer disposed between the substrate and the magnetic layer. The underlayer is made of a material having a Ga3Pt5 crystalline structure, most preferably Ni5Al3. Several intermediate layers, disposed between the underlayer and the magnetic layer may also be included.

Abstract: A magnetic recording system includes an in-plane magnetic recording medium having a magnetic layer fabricated on a single underlayer or on a plurality of underlayers respectively fabricated on a substrate; a driver unit for driving the in-plane magnetic recording medium in a write direction; a magnetic head having a read unit and a write unit; a unit for moving the magnetic head relative to the in-plane magnetic recording medium; and a read/write signal processing unit for reading an output signal from the magnetic head and writing an input signal to the magnetic recording media, wherein the read unit of the magnetic head is a magnetoresistive head and the single underlayer or at least one of the plurality of underlayers is made of Co-containing amorphous material or fine crystal material, or is made of alloy material, the alloy material having as the main components at least one element selected from a group consisting of Cr, Mo, V and Ta and containing at least one element selected from a group consisting o

Abstract: A bi-crystal magnetic recording media, i.e., media with Cr(200) and Co(11.0) orientations, comprising non-metallic substrates, CrTi or NiPOx seed layers, B2-structured CoTi first underlayers, Cr-alloy second underlayers, and Co-alloy magnetic layers have high coercivity, high SMNR and high areal recording density.

Abstract: An organic substrate having optically-active layers deposited by magnetron sputtering and a preparation process for it are provided. Gas pressure used for carrying out better adhesion by sputtering is high, comprised between 0.8 and 5.0 Pa. Sputtering is particularly suitable for targets of Si, Ti, Zr and organic substrates with or without anti-abrasive coating. Improved adhesion of thin films is obtained.

Abstract: A fastener member for being secured to the surface of a foam body during a molding process in a mold form. The fastener member includes an elongate base having upper and lower opposed faces with fixating elements positioned on the lower face of the base for being positioned within and protected by a mold cavity in a wall of the mold form against foam contamination during the molding process. First and second opposed, elongate sealing ramps positioned on the upper face of the base by respective proximal ends and diverge outwardly and upwardly at an angle oblique to the base and define respective outwardly-extending distal ends. The base is sized to fit within the mold cavity with outer surfaces of the respective first and second ramps engaging and sealingly contacting respective upper wall corners of the mold at points of contact intermediate the proximal and distal ends.

Abstract: An ultra-high density information recording media has an inorganic compound layer 12 on a substrate 11, and in the inorganic compound layer 12, an oxide of at least one kind selected from silicon oxide, aluminum oxide, titanium oxide, tantalum oxide, and zinc oxide exists in an amorphous state at a grain boundary of crystal grain of an oxide of at least one kind selected from cobalt oxide, iron oxide, and nickel oxide. The media has a magnetic layer 13 made of an artificial lattice multilayer obtained by alternately laminating a Co layer or an alloy layer consisting of Co as a main phase and a metal element layer of at least one kind selected from Pt and Pd onto the layer 12. Thus, a distribution of magnetic properties serving as a pinning site of the movement of a magnetic wall in case of recording information to the magnetic layer 13 is formed in the magnetic layer 13.

Abstract: An improved and novel device and fabrication method for a magnetic element, and more particularly a magnetic element (10) including a first electrode (14), a second electrode (18) and a spacer layer (16). The first electrode (14) and the second electrode (18) include ferromagnetic layers (26 & 28). A spacer layer (16) is located between the ferromagnetic layer (26) of the first electrode (14) and the ferromagnetic layer (28) of the second electrode (16) for permitting tunneling current in a direction generally perpendicular to the ferromagnetic layers (26 & 28). The device includes insulative veils (34) characterized as electrically isolating the first electrode (14) and the second electrode (18), the insulative veils (34) including non-magnetic and insulating dielectric properties.

Abstract: Magnetic recording medium includes at least two layers having different magnetic anisotropy constants formed on a substrate and the perpendicular magnetic anisotropy of the second magnetic film of those magnetic films, far from the substrate surface, made equal to or larger than that of the first magnetic film near to the substrate surface, thus improving the magnetic isolation.

Abstract: A thin film magnetic media structure comprising a pre-seed layer CrTi is disclosed. The CrTi pre-seed layer presents an amorphous or nanocrystalline structure. The preferred seed layer is RuAl. The use of the CrTi/RuAl bilayer structure provides superior adhesion to the substrate and resistance to scratching, as well as, excellent coercivity and signal-to-noise ratio (SNR) and reduced cost over the prior art.

Abstract: The present invention provides a magnetoresistive element in which discontinuity at a barrier layer interface is provided by utilizing a layered-perovskite oxide, and a device in which the foregoing magnetoresistive element is used. The element of the present invention includes a layered-perovskite oxide having a composition expressed by a formula L2(A1−zRz)2An−1MnO3n+3+x and including a (L-O)2 layer in its crystalline structure, and a pair of ferromagnetic bodies formed in contact with the layer perovskite oxide so as to sandwich the oxide. In response to bias application via the (L-O)2 layer, a magnetoresistive tunnel effect appears.

Abstract: A series of bulk-size magnetic/insulating nanostructured composite soft magnetic materials with significantly reduced core loss and its manufacturing technology. This insulator coated magnetic nanostructured composite is comprises a magnetic constituent, which contains one or more magnetic components, and an insulating constituent. The magnetic constituent is nanometer scale particles (1-100 nm) coated by a thin-layered insulating phase (continuous phase). While the intergrain interaction between the immediate neighboring magnetic nanoparticles separated by the insulating phase (or coupled nanoparticles) provide the desired soft magnetic properties, the insulating material provides the much demanded high resistivity which significantly reduces the eddy current loss. The resulting material is a high performance magnetic nanostructured composite with reduced core loss.

Abstract: A semi-hard magnetic alloy for activation strips in magnetic anti-theft security systems is disclosed that contains 8 to 25 weight % Ni, 1.5 to 4.5 weight % Al, 0.5 to 3 weight % Ti and balance iron.

Abstract: A ferromagnetic metal powder having an average long axis length of from 30 to 65 nm, a crystallite size of from 80 to 130 angstroms, a saturation magnetization (&sgr;s) of from 75 to 130 A·m2/kg, and an average oxide layer thickness of from 1.5 to 2.5 nm; a method of producing a ferromagnetic metal powder comprising: reducing the oxide of a ferromagnetic metal element to obtain the ferromagnetic metal powder, subjecting the ferromagnetic metal powder to gradual oxidation treatment to make as 120 to 150 A·m2/kg, adhering at least one element selected from Al, Y, lanthanoid, Zr and W to the ferromagnetic metal powder in water, performing heat treatment, and again performing gradual oxidation treatment; and a magnetic recording medium comprising a support having provided thereon a magnetic layer mainly comprising a ferromagnetic metal powder and a binder, wherein the magnetic layer containing the ferromagnetic metal powder has a thickness of from 0.04 to 0.

Abstract: A material, preferably a magnetic data storage disc, includes a carbon layer covering at least a portion of a magnetic substrate and a crosslinked fluoropolymer layers covering at least-a portion of the carbon layer. The crosslinked polymer layer has a thickness less than about 40 angstroms, and the carbon layer has a thickness less than about 100 angstroms. Preferred fluoropolymers include, for example, perfluoropolyethers. In some embodiments, the crosslinked fluoropolymer layer has a thickness at one point on the carbon layer greater than the thickness crosslinked fluoropolymer layer at another point on the carbon layer. The crosslinking generally is performed by irradiating the lubricant material on the carbon layer.

Abstract: A magnetic recording medium according to the invention includes a plastic substrate, a non-magnetic under-layer on the substrate, a magnetic layer including cobalt on the under-layer, a protective film on the magnetic layer, and a liquid lubricant layer on the protective film. The under-layer is composed of a chromium alloy having a body centered cubic lattice structure, and containing at least one element selected from the group consisting of Zr, Nb, Mo, Ru and Pd in a total amount of at least 15 at %, or containing at least one element selected from the group consisting of Hf, Ta, W, Re, Pt and Au in a total amount of at least 10 at %. The amount of cobalt dissolved out of the magnetic layer is limited by performing sputtering deposition of at least the magnetic layer at low pressures of argon.

Abstract: Corrosion resistant magnetic thin film media are fabricated using a CoCr magnetic layer having a stabilized protective chromium oxide film thereon. Stabilization of the protective chromium oxide film is achieved by incorporating a stabilizing element, such as Mo, V, Mn, Nb, Ni or Si, in the magnetic layer, thereby enabling elimination of the protective overcoat, e.g., C-containing protective overcoat, or forming the protective overcoat at a significantly low thickness of less than about 20 Å, e.g., up to about 1 Å. Embodiments include forming a magnetic layer comprising Co and Cr on an underlayer, and then forming a thin magnetic layer containing Co and Cr with the chromium oxide stabilizing element thereon. Embodiments further include introducing the chromium oxide stabilizing element by diffusion or ion implantation into a sputter deposited Co—Cr magnetic alloy layer.

Abstract: An improved magnetic medium has a metal or semiconductor surface in which the surface of the magnetic medium has an approximate monolayer of fullerene molecules bonded to the metal or semiconductor surface. The bond strength between the fullerene molecules and the surface is stronger than the fullerene-fullerene intermolecular bond strength. The magnetic media can be used in the production of components for data storage system, in particular heads with magnetic transducers and magnetic or optical-magnetic discs. In methods for forming the fullerene coatings, an approximate monolayer of fullerene molecules are deposited on a metal or semiconductor surface substantially free of contaminants.

Abstract: A spin-valve thin-film magnetic element includes a substrate; an antiferromagnetic layer; a pinned magnetic layer in contact with the antiferromagnetic layer, the magnetization direction of the pinned magnetic layer being pinned by an exchange coupling magnetic field with the antiferromagnetic layer; a nonmagnetic conductive layer in contact with the pinned magnetic layer; a free magnetic layer in contact with the nonmagnetic conductive layer, the magnetization direction of the free magnetic layer being aligned in a direction perpendicular to the magnetization direction of the pinned magnetic layer; and a back layer composed of a nonmagnetic conductive material formed in contact with the free magnetic layer at the opposite side of the nonmagnetic conductive layer. The back layer is composed of at least one metal selected from the group consisting of Ru, Pt, Ir, Rh, Pd, Os, and Cr.

Abstract: A disposable absorbent article including at least one fusion bond accomplished by the application of an electromagnetic field and a method for producing the fusion bond are disclosed. The article includes a first component, a second component underlying the first component; and a third component underlying the second component. The fusion bond is disposed directly above the third component and bonds the first component to second component. The fusion bond includes a receptor susceptible to an electromagnetic field. The first component of the article has an outer surface that includes at least one receptor area disposed directly above the fusion bond. The receptor area can have a tactile property that is a substantially equal to a tactile property of the outer surface surrounding the receptor area.

Abstract: A magnetic recording medium has a non-magnetic substrate, an under layer, a magnetic layer, and a protective layer in the recited order. The magnetic layer consists of a plurality of magnetic components embedded in a pattern in an isolating component. Each magnetic component includes at least one magnetic component of large coercive force and one of a magnetic component of small coercive force. The two components abut each other. In one embodiment the two components form one or more alternating layers. In another embodiment, one of the components has a recess in its upper surface which is filled with the other component. In still another embodiment, the two components are disposed side by side passing through the isolating component.

Abstract: A sensor for measuring magnetostriction of and/or magnetic thin film is constructed by depositing a thin film nonferromagnetic electrically insulating layer followed by a thin film layer of a sensor material which is piezoresistive and nonferromagnetic. The insulating and the piezoresistive film can be etched into an appropriate pattern and orientation to provide sensitivity to strain in the magnetic film. The magnetostrictive strain in the magnetic film is induced by a known magnetic field which produces a corresponding strain in the piezoresistive film which can be measured as a change in the electrical resistance which can be detected by external probes or other measuring means. The measurement of the magnetostriction can be performed as a part of the manufacturing process for wafers with a plurality of thin film magnetic heads thereon and does not require that the wafers be removed to a laboratory.

Abstract: For protecting a copyright, stored digital information on a recording medium is attenuated in a certain period of time. For this purpose, the thickness of a magnetic layer and the diameter of magnetic crystal grain are changed to control the effect of the thermal oscillation on magnetization of a crystalline region to thereby provide the recording medium with digital information retained for a certain period of time, and attenuated along with time.

Abstract: A magnetic recording medium has a magnetic recording film in which the magnitude of saturation magnetization Ms(T=5° K) at 5° K and magnitude of saturation magnetization Ms(T=300° K) at 300° K satisfy: Ms(T=300° K)/Ms(T=5° K)≧0.75. The recording medium enables the high-density recording, and a magnetic recording apparatus using this recording medium can yield a sufficiently high reproduction signal level within the operating temperature range of the apparatus.

Abstract: The present invention provides a paint masking article that is easy to apply and reusable. It is suitable for use on any ferromagnetic surface but is particularly well suited for body repair work on automobiles. The paint masking article comprises a flexible sheet of paint masking material, a flexible magnetic strip, and means for securing the magnetic strip within a folded edge of the paint masking material. Methods for making and using the paint masking articles are also provided.

Abstract: A magnetic tunnel junction is made up of two ferromagnetic layers, one of which has its magnetic moment fixed and the other of which has its magnetic moment free to rotate, an insulating tunneling barrier layer between the ferromagnetic layers for permitting tunneling current perpendicularly through the layers. The insulating barrier is preferably formed by the oxidation of a thin metallic alloy layer of particular materials which lead to a nonmagnetic barrier having a relatively low barrier height. These low barrier height insulating materials allow for the formation of a magnetic tunnel junction with a relatively thick barrier while maintaining a low resistance that is suitable, for example, in magnetoresistance read head applications.

Abstract: In a thin film magnetic disk, a crystalline CrNi pre-seed layer is sputtered onto a substrate such as glass, followed by a RuAl seed layer. The CrNi pre-seed layer reduces grain size and its distribution, and improves in-plane crystallographic orientation, coercivity (Hc) and SNR. In a preferred embodiment the RuAl seed layer is followed by a Cr alloy underlayer. In a preferred embodiment the Cr alloy underlayer is followed by an onset layer and a magnetic layer, or by two or more magnetic layers antiferromagnetically coupled through one or more spacer layers. The crystalline CrNi pre-seed layer allows use of a thinner RuAl seed layer which results in smaller overall grain size, as well as a reduction in manufacturing cost due to relatively high cost of ruthenium. The CrNi pre-seed layer also allows use of a thinner Cr alloy underlayer which also contributes to reduce overall grain size.

Abstract: A magnetic storage device has a recording density of over 5 gigabits per square inch. In the magnetic layer, the magnetic crystal grains of the granular structure are separated by a nonmagnetic phase. The typical crystal grain is in the approximate shape of a sphere or an ellipsoid. The thickness of the magnetic crystal grains, which is in the direction perpendicular to the surface of the film, is smaller than that of the thickness of the magnetic film. The ratio of the coercive force which is measured in the circumferential direction to the coercive force which is measured in the radial direction, which is the orientation ratio of the coercive force, is larger than 1.0, but preferably not greater than 3.0. Further, the area fraction of the magnetic grains having an extended axis within 30° from the circumferential direction is equal to or more than 45%.

Abstract: Double photolithography is used to produce an under-layer of protective and filtering photoresist over a substrate that will have channels milled with a FIB. Secondary layers are applied with precision on top of the first layer in order to define the precise patterns to be milled and to provide targeting and alignment fiducials.

Abstract: An antiferromagnetically coupled layer structure for magnetic recording wherein the top ferromagnetic structure is a bilayer structure including a relatively thin first sublayer of ferromagnetic material in contact with the coupling/spacer layer. The first sublayer has a higher magnetic moment than the second sublayer. The layer structure of the invention results improved manufacturability and improved performance. A preferred embodiment of a layer structure according to the invention includes: a bottom ferromagnetic layer preferably of CoCr; an antiferromagnetic coupling/spacer layer preferably of Ru; and a top ferromagnetic structure including a thin first sublayer of material preferably of CoCr, CoCrB or CoPtCrB, and a thicker second sublayer of material preferably of CoPtCrB with a lower moment than the first sublayer.

Abstract: To provide an improved perpendicular magnetic recording medium suitable for high density magnetic recording. In a perpendicular magnetic recording medium comprising a perpendicular magnetic layer and protective layer provided on a non-magnetic substrate via a soft magnetic backlayer, a polycrystalline MgO film is inserted between the soft magnetic backlayer and perpendicular magnetic layer.

Abstract: A magnetic recording medium on glass or Al substrates with film structures of CrV/NiAl/CrMo/CoCrTa/CoCrPtTaNbB and CrMo/CoCrTa/CoCrPtTaNbB exhibit high coercivity and high signal-to-medium noise ratio. The medium can be used for high-density longitudinal magnetic recording. Embodiments include forming a sub-seed layer on a NiP-plated aluminum substrate, and sequentially depositing a seed layer, an underlayer, an intermediate layer and a magnetic layer on the substrate. The magnetic layer contains at least six elements, including Co, Cr and B.

Abstract: Electrical steel sheets having superior magnetic properties, anti-noise properties, and workability, are ideal for use a compact iron core material in electric apparatuses, such as compact transformers, motors, and electric generators. A totally new electrical steel sheet and a manufacturing method therefor are proposed, in which the electrical steel sheet is not only most advantageous in magnetic properties but also advantageous from economic point of view. That is, the electrical steel sheet of the present invention is composed of from about 2.0 to 8.0 wt % Si, from about 0.005 to 3.0 wt % Mn, from about 0.0010 to 0.020 wt % Al, balance essentially iron. The magnetic flux density B50(L) in a rolling direction and the magnetic flux density B50(C) in the direction perpendicular thereto are 1.70 T or more, and the B50(L)/B50(C) is 1.005 to 1.100.

Abstract: A magnetic recording medium is constructed to include a substrate, a magnetic layer made of a Co or Co-based alloy, and an underlayer disposed between the substrate and the magnetic layer. The underlayer is made of an ordered intermetallic material of FCC L12 or FCT L10 crystalline structure, so that c-axis of the magnetic layer is aligned in a predetermined direction.

Abstract: A magnetic storage medium has a non-magnetic substrate and a recording layer. The recording layer comprises a non-magnetic matrix and crystal grains consisting of a ferromagnetic material. Each of the crystal grains dispersed in the recording layer is a columnar shaped grain which penetrates a suface of the recording layer and has height of 30 nm or less, and a mean value of grain sizes of the crystal grains in an internal direction of the recording layer is 15 nm or less. (Ku·V)/(kB·T) is not less than 60. A mean value Hk of anisotropic magnetic fields of the plurality of crystal grains is 20 kOe or less.

Abstract: A magnetic head in a magnetic storage system is provided in which materials that do not individually display high permeability and low coercivity are satisfactorily employed in a write head when coupled to adjacent high permeability layers. The magnetic head includes a gap layer which separates a pair of poles. At least one pole of the pair of poles includes a pole layer formed of a high permeability material and a seed layer adjacent to the pole layer. The seed layer is formed of a high moment low permeability material having a high saturation magnetic moment greater than 2.1 Tesla and a low permeability of about 10-100. The high permeability material of the pole layer causes the permeability of the adjacent seed layer to substantially increase from about 10-100 to about 1400-1600, thereby providing a pole with high permeability and high saturation moment. In addition, a method of forming a magnetic head for use in a magnetic storage system is provided.

Abstract: A magnetoresistive sensor including a lower electrode layer, a nanotube structure film composed of an insulator matrix and a plurality of nanotubes dispersively arranged in the insulator matrix, a magnetoresistive film provided on the nanotube structure film, and an upper electrode layer provided on the magnetoresistive film. Each nanotube is composed of a circular tubular nonmetal and a circular cylindrical metal surrounded by the circular tubular nonmetal. The nanotube structure film is partially etched at its central region to make conduction of the upper electrode layer and the lower electrode layer through the magnetoresistive film and the circular cylindrical metal of each nanotube present at the central region.

Abstract: A magnetic recording medium in which a seedlayer includes an aluminum-containing intermetallic nitride for improved performance.

Abstract: A magnetic recording medium includes a highly permeable magnetic layer proximal to a recording layer. During recording, the permeable magnetic layer modifies the recording field from a recording head to produce consistently shaped recording transitions with a significant perpendicular component. The transitions are consistently shaped even though the distance between the recording head and the surface of the medium may change. Transitions so formed result in a reduction of noise from the medium surface roughness. The permeable magnetic layer further reduces noise caused by stray dipole fields.

Abstract: A magnetic recording medium having a high coercive force of a ferromagnetic metal layer, a high anisotropic magnetic field and/or normalized coercive force, and adaptable to high density recording. The magnetic recording medium includes a substrate body and a ferromagnetic metal layer containing at least Co and Cr formed thereon via a metallic underlying layer of Cr. Magnetic inversion is utilized for the recording. A first region which penetrates through the ferromagnetic metal layer and in which Cr is segregated are formed among the crystal grains constituting the ferromagnetic metal layer. The Cr concentration in the intermediate portions of the first region in the direction of thickness of the ferromagnetic metal layer is smaller than that of the portions near the surface and near the metallic underlying layer.

Abstract: A method of forming a magnetic assembly having at least one magnetic layer having dimensions of thickness, width and length, and at least one printable substrate layer having dimensions of thickness, width and length, including the steps of providing a molten magnetic composition including about 70 wt-% to about 95 wt-% of at least one magnetic material and about 5 wt-% to about 30 wt-% of at least one thermoplastic binder, forming the magnetic composition into a magnetic layer at an elevated temperature and directly applying the magnetic layer at an elevated temperature to a first surface of a printable substrate layer wherein. An adhesion promoting composition may be further provided between the magnetic layer and the printable substrate layer for improving adhesion between the magnetic layer and the printable substrate layer.

Abstract: A magnetic recording medium is constructed to include a non-magnetic underlayer, and a magnetic layer including a compensation layer provided on the nonmagnetic underlayer, and a recording layer provided on the compensation layer, where the compensation layer has a thickness of 3 to 15 nm and is made of Co or a Co alloy with a Curie temperature of approximately 30 to 150° C., and the recording layer has a thickness of 10 to 30 nm and is made of a Co alloy with a Curie temperature of approximately 250 to 800° C.

Abstract: A fluoropolyether having a nonfunctional silane end group is applied to a magnetic recording medium to form a lubricant topcoat thereon. In an embodiment of the present invention, no less than about 70% of the lubricant applied to the magnetic recording medium forms a bonded topcoat thereto.

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: Disclosed is a magnetic recording medium capable of reducing noise and an error rate of the medium. The medium comprises a nonmagnetic substrate; a magnetic layer formed on the surface of the nonmagnetic substrate directly or through a nonmagnetic underlayer; and a protective layer formed on the magnetic layer; wherein the magnetic recording medium satisfies the following relationships: −0.5≦{Hc(1)−Hc(p)}/Hc(1)≦0.3 Hc(1)≧2 kOe 20 G×&mgr;m≦Br(1)×t≦100 G×&mgr;m where Hc(1) indicates a corecivity of the magnetic layer measured in the longitudinal direction; Hc(p) indicates a coercivity of the magnetic layer measured in the perpendicular direction; Br(1) indicates a remanent magnetization of the magnetic layer measured in the longitudinal direction; and “t” indicates a layer thickness of the magnetic layer.

Abstract: A magnetic recording medium includes a substrate, an underlayer provided on the substrate, a Co alloy magnetic film formed through the underlayer, and a protective film for protecting the magnetic film, wherein the underlayer has a two-layer structure of an lower underlayer contacted with the substrate and an upper underlayer contacted with the Co alloy magnetic film, the upper underlayer is a Co—Crx—My alloy film having a hexagonal close-packed structure, where 25 atomic %≦x+y≦50 atomic %, 0.5 atomic %≦y, nonmagnetic element M is one selected from the group of elements B, Si, Ge, C, Al, P, Ti, V, Nb, Zr, Hf, Mn, Rh, Os, Ir, Re, Pd, Pt, Mo, Ta, W, Ag and Au. Thereby the medium can be increased in its coercive force and can be improved in its thermal stability characteristics.

Abstract: A perpendicular magnetic recording medium having a substrate and an annealed magnetic layer comprising boron on the substrate, the magnetic layer being a single film and having an L10 structure, and a process for manufacturing the perpendicular magnetic recording medium are disclosed.