Abstract: A magnetic recording medium containing a non-magnetic substrate, an orientation-determining layer for causing the non-magnetic undercoat layer assume to have a predominant orientation plane of (200), a non-magnetic undercoat layer, a magnetic layer, and a protective layer, in order, is disclosed. The non-magnetic undercoat layer 3 has a bcc structure; the orientation-determining layer has a crystal structure in which columnar fine crystal grains are inclined in a radial direction; and the ratio of a coercive force in a circumferential direction of the magnetic layer (Hcc) to a coercive force in a radial direction of the magnetic layer 4 (Hcr)is more than 1. The magnetic layer includes a plurality of magnetic films and having an hcp structure and a predominant orientation plane of (110), and permits antiferromagnetic bonding to be formed therebetween.

Abstract: Laminated magnetic recording medium with two Co-containing layers separated by a non-magnetic interlayer is stablished by Ru-containing layers between the recording layers and Co-containing stablization layers through antiferromagnetic coupling.

Abstract: A spin valve thin-film magnetic element has an improved rate of change in resistance (&Dgr;R/R) that can be used for a narrower magnetic track. The spin valve thin-film magnetic element has a laminate that include an antiferromagnetic layer, a pinned magnetic layer, a non-magnetic conductive layer, a free magnetic layer, a back layer, specular-reflection layers and a pair of electrode layers formed at the two sides of the laminate. Preferably the specular reflection layer includes an oxide, such as &agr;-Fe2O3 or NiO, or a half-metal Heusler alloy, such as NiMnSb or PtMnSb.

Abstract: A magnetic recording medium includes a first underlying film of a NiTa alloy having a nonmagnetic amorphous structure and formed on a nonmagnetic substrate, and a second underlying film made of an alloy containing Cr and Ti, further a first magnetic film of a CoCrPt alloy, a nonmagnetic intermediate film of Ru and a second magnetic film of a CoCrPtB alloy that are serially formed over the first underlying film, wherein oxygen locally exists in an interface between the first underlying film and the second underlying film.

Abstract: A disk for a hard disk drive. The disk includes a first layer of magnetic material located over a substrate, an intermediate layer located over the first magnetic layer and a second layer of magnetic material located over the intermediate layer. The second layer may include cobalt and chromium. The intermediate layer may include titanium. The first magnetic layer include iron, hafnium and nitrogen (FeHfN). This composition of the first magnetic layer shows higher saturation magnetization and lower roughness, and increases the nucleation field of the disk.

Abstract: Spindle-shaped magnetic alloy particles containing Fe and Co as main components of the present invention have a cobalt content of 20 to 50 atm % (calculated as Co) based on whole Fe; an average major axis diameter (L) of 0.03 to 0.10 &mgr;m; a coercive force value of 159.2 to 238.7 kA/m (2,000 to 3,000 Oe); a crystallite size of 100 to 160 Å; and an activation volume (Vact) of 0.01 to 0.07E-4 &mgr;m3. A high-density magnetic recording medium produced by using such spindle-shaped magnetic alloy particles containing Fe and Co as main components, have an excellent output characteristics in a short wavelength region, a considerably reduced noise and an excellent storage stability.

Abstract: A magnetic recording medium is provided with at least one exchange layer structure, and a magnetic layer formed on the exchange layer structure. The exchange layer structure includes a ferromagnetic layer and a non-magnetic coupling layer provided on the ferromagnetic layer and under the magnetic layer.

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: The coercivity of a magnetic recording medium such as a magnetic disk is determined by providing at least two magnetic layers in the recording medium with the relative thicknesses of the two magnetic layers determining coercivity without the need for changing substrate temperature, underlayer thickness or substrate biasing during manufacture. Each magnetic layer is a cobalt alloy of different composition and intrinsic magnetic properties. Importantly, the coercivity can be modified without adversely affecting remanence or squareness of the hysteresis transition region for the recording medium.

Abstract: The present invention relates to an information carrier which, by means of magnetism, can be applied to a suitable substrate. This information carrier consists for an important part of plastic, while at least one layer of that plastic comprises metal particles dispersed therein.

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: A magnetic sheet assembly for application to a device adapted for magnetic separation, the magnetic sheet assembly comprising: a magnetic sheet; a permanent, pressure sensitive adhesive; a carrier sheet; and a non-permanent pressure sensitive adhesive. Also provided is a method of mounting and removably adhering the magnetic sheet assembly to a surface of a device for magnetic separation, the method comprising the steps of aligning the magnetic sheet assembly with the surface of the device; and pressing the aligned magnetic sheet assembly in placing its non-permanent adhesive face into adhesive contact with the surface of the device.

Abstract: A magnetic recording medium, comprises a substrate; and a Co-containing spinel-type iron oxide thin film formed on the substrate, having a Co content of 1 to 20 mol % based on Fe, a coercive force value of not less than 159 kA/m (2,000 Oe), a thickness of 5 to 200 nm, a center line average height Ra of 0.1 to 0.8 nm and a maximum height (Rmax) of not more than 10 nm. The magnetic recording medium is capable of exhibiting a relatively high coercive force, especially a coercive force of not less than 159 kA/m (2,000 Oe) despite as small a film thickness as not more than 200 nm, and an excellent surface smoothness.

Abstract: Pyrogenic, oxidic particles contain superparamagnetic metal oxide domains with a diameter of 3 to 20 nm in a non-magnetic metal or non-metal oxide matrix. The particles display a chloride content of 50 to 1000 ppm. The particles are produced by pyrogenic processes by mixing the precursor of the superparamagnetic domains and the precursor of the non-magnetic metal or non-metal oxide matrix in a flame with air and/or oxygen and fuel gas and reacting this mixture in a flame. The particles can be used as ferro fluids, for example.

Abstract: Improved multilayer magnetic superlattice structures, such as (Co/Pt)n and (Co/Pd)n, having predetermined, very high perpendicular magnetic coercivities are formed by sputter deposition of predetermined thickness, ultra-thin seed layers on the substrate prior to formation thereon of the superlattice structure by sputtering at at least a predetermined minimum sputtering gas pressure. The multilayer magnetic superlattice structures are advantageously utilized in the formation of thermally stable, perpendicular magnetic recording (MR) media having very high areal recording densities.

Abstract: A process for producing a glass substrate for a magnetic recording medium by forming a surface roughness in a main surface of a glass plate that has been formed into a disk shape, includes: imparting a processing mark having a permanent strain to the main surface of the glass plate in a circumferential direction thereof; and chemically etching the whole main surface of the glass plate, so as to form the surface roughness.

Abstract: A magnetic recording medium comprising a non-ferromagnetic substrate and a magnetic recording film formed on the substrate with an underlayer interposed therebetween, wherein the magnetic recording film comprises a plurality of magnetic layers and an interlayer made of a material having a B2 crystal structure or an interlayer made of Ru, disposed between the adjacent magnetic layers.

Abstract: Composites comprising porous polymeric membrane films meeting the following equation: 75 MPa<(longitudinal membrane tensile modulus+transverse membrane tensile modulus)/2, wherein at least a portion of the porosity of the membrane is imbibed with resin and methods for making the same. The composites have unusually high resistance to fracture and catastrophic failure.

Abstract: A method of magnetic recording/reproducing is disclosed, which comprises reproducing with a magnetoresistive head (MR head) signals recorded in a magnetic recording medium comprising a support having thereon a magnetic layer comprising mainly ferromagnetic particles and a binder, wherein the MR head has an element thickness of 50 nm or smaller and the ferromagnetic particles are hexagonal-ferrite magnetic particles having an average tabular diameter of from 10 to 40 nm and an average tabular thickness smaller than the element thickness of the MR head used for reproduction.

Abstract: A method is provided for coating one or more fluid layers on a substrate to form magnetic recording media such as magnetic tape and diskettes. The method takes advantage of fluid coating formulations having a particular rheology that enables the coating of one or more magnetic layers with reduced thicknesses while achieving increased coating speeds. With proper rheology, one or more layers can be coated on a substrate traveling at increased speeds while maintaining desired coating thicknesses.

Abstract: Composites comprising porous polymeric membrane films meeting the following equation: 75 MPa<(longitudinal membrane tensile modulus+transverse membrane tensile modulus)/2, wherein at least a portion of the porosity of the membrane is imbibed with resin and methods for making the same. The composites have unusually high resistance to fracture and catastrophic failure.

Abstract: A magnetic medium having at least two intermediate layers between an underlayer and a magnetic layer. The first intermediate layer is designed to provide a good lattice match to the underlayer, while the second intermediate layer is designed to provide a good lattice match to the magnetic layer. Typically, the underlayer has one structure, such as body centered cube, while the magnetic layer has a second structure such as hexagonal close pack. In preferred embodiments, the transition from the one structure to the other structure occurs in the intermediate layers. For example, the first intermediate layer may be a hexagonal close pack structure. Because of the mismatch between the underlayer and the first layer, there may be crystal defects in this first intermediate layer. However, any remaining stress and mismatch is absorbed through the second layer, so that the second layer presents a substantially defect-free surface on which the magnetic layer may grow.

Abstract: A magnetic recording medium (300) includes a substrate (1) and on the substrate (1) a first underlying layer (32), a second underlying layer (33), a magnetic layer (34), and a protective layer (35). Because of the existence of the first underlying layer (32) of Hf, initial growth layer having no specific crystal structure is prevented from growing in the second underlying layer (33). The second underlying layer (33) has a structure in which CoO particles having a cross section of a regular hexagon and separated by SiO2 portion are arranged in honeycomb. Since magnetic particles are epitaxially grown from CoO particles, the size of the magnetic particles and particle size distribution can be controlled, and the magnetic interaction between magnetic particles can be lessened. The underlying layer (33) and the protective layer (35) are formed by ECR sputtering. Such a magnetic recording medium is free from noise and thermal fluctuation, and ultrahigh recording density over 40 Gbit/inch2 is realized.

Abstract: A magnetic memory device includes a first wiring which runs in the first direction, a first metal layer which is arranged above the first wiring, a first magneto resistive effect element which is arranged in a predetermined region on the first metal layer, a first contact layer which is arranged on the first magneto resistive effect element, a second wiring which runs in the second direction different from the first direction, is arranged on the first contact layer, and has a projection that covers the top of the first contact layer, and a first insulating film which is buried around the first metal layer, first magneto resistive effect element, first contact layer, and second wiring, and has a surface flush with that of the second wiring.

Abstract: A magnetic recording medium comprising, in order, a non-metallic substrate; an amorphous metallic film having an amorphous structure; a crystal-structure-regulating film of NiP-based alloy; and a non-magnetic undercoat film and a magnetic film; and wherein the crystal-structure-regulating film has a film thickness of 50 nm or less, and a total film thickness of the amorphous metallic film and the crystal-structure-regulating film is at least 60 nm is disclosed.

Abstract: Provided are a double-layer perpendicular magnetic recording medium having a high medium S/N at an areal recording density of 50 Gbits or more per square inch, and a magnetic storage apparatus having excellent reliability with a low error rate. The perpendicular magnetic recording medium is formed by sequentially laminating a domain control layer, an amorphous soft magnetic underlayer, an intermediate layer, and a perpendicular recording layer on a substrate. The domain control layer is a triple-layer film formed by laminating a first polycrystalline soft magnetic layer, a disordered antiferromagnetic layer, and a second polycrystalline soft magnetic layer from a substrate side.

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: A magnetic recording medium having a non-magnetic support, at least one primer layer on one surface of the support, a magnetic layer on the primer layer and a back coat layer on the other surface of the non-magnetic support, in which the support has a thickness of 2 to 5 &mgr;m, the surface roughness (Ra) of the support on its surface carrying the primer layer and the magnetic layer is from 2.5 nm to 20 nm, the thickness of the primer layer is 1.5 &mgr;m or less, and the primer layer contains 2 to 30 % by weight, based on the weight of all inorganic powder in the primer layer, of alumina powder having a particle size of 0.01 &mgr;m to 0.1 &mgr;m.

Abstract: There is provided a composite magnetic tape which can be easily applied irrespective of the inside or outside of an electronic equipment, prevent radiation of undesired electromagnetic waves from the inside of the equipment and reflection into the inside of the equipment, and shield electromagnetic noise from the outside of the equipment. The tape may be in the form of an adhesive tape or a self-welding tape. The tape is constituted of a composite magnetic layer formed by dispersing soft magnetic powder into an organic binding agent. Alternatively, it may have a stacked structure of a composite magnetic layer and a conductor layer.

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: 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: The present invention provides a magnetic recording medium including at least a nonmagnetic undercoat layer, a nonmagnetic metallic intermediate layer, a magnetic layer, a protective film, and a liquid lubricant layer sequentially laminated on a nonmagnetic substrate, wherein the magnetic layer contains crystal grains having ferromagnetism and nonmagnetic grain boundaries surrounding the crystal grains, and the nonmagnetic metallic intermediate layer contains at least one layer, and the crystal structure of each layer being a hexagonal close-packed structure; and a method for producing the magnetic recording medium. The magnetic recording medium shows high coercive force Hc and a low medium noise, and its manufacturing cost is also low.

Abstract: A manufacturing method of a domain wall displacement type magneto-optical recording medium comprises the steps of depositing a magnetic layer on a substrate to prepare a disc, and irradiating the magnetic layer with a converged light beam while applying a magnetic field and annealing the magnetic layer a converged light beam between information tracks.

Abstract: The present invention provides a high-density, low-noise magnetic recording medium. This magnetic recording medium includes a substrate, a non-magnetic underlayer formed on the substrate, and a magnetic recording layer formed on the underlayer. The magnetic recording layer contains cobalt as the main component, 10 atm % to 18 atm % of chromium, 5 atm % to 20 atm % of platinum, and 10 atm % to 20 atm % of boron.

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 base film for magnetic recording media, comprising a film layer containing inert fine particles and having an agglomeration rate of the inert fine particles on the surface of the film of 4 to 20%, or a film layer containing inert fine particles and an ester wax of an aliphatic monocarboxylic acid having 8 or more carbon atoms and a polyhydric alcohol and having a water contact angle of the exposed surface of 70 to 90°. A magnetic recording medium, particularly a metal deposited thin film magnetic recording medium comprising this base film is excellent in electromagnetic conversion characteristics.

Abstract: A method of influencing variations in composition of thin films is described. The elemental plasma field distribution in sputtering systems is manipulated by generating a nonuniform electric field along a surface of the substrate to alter the composition by differentially re-sputtering the target elements. The nonuniform electric field is applied by one or more electrodes in contact with a conductive surface or by using an RF bias signal. The nonuniform electric field is used to modulate the kinetic energy of the ions generated in the plasma which strike the thin film's surface. Since the kinetic energy and the mass of the sputtering gas ions and neutrals affect the re-sputtering rate, the nonuniform electric field differentially affects the elements being deposited according to mass. By applying varying electric potentials at a plurality of points on a conductive surface of a substrate, the electric field across the surface of the substrate can be modulated in a variety of patterns.

Abstract: The present invention is directed to a method and a device for the production of security elements for electronic article surveillance, the security elements being comprised of at least two layers, as well as to a web material manufactured by means of the method the present invention proposes a simple, economical method, a corresponding device for the production of web material, as well as to a web material manufactured by the method for the purpose of electronic article surveillance. With regard to the method of the present invention, it is accomplished in that sections of a predetermined length cut from a second material web are conveyed in a direction transverse to the running direction of a first continuous material web and are applied to the first material web.

Abstract: A magnetic recording medium capable of suppressing the effects of thermal agitation and simultaneously reducing the average grain diameter and the standard deviation of magnetic crystal grains constituting a ferromagnetic metal film, without changing the film thickness of a metal under-layer or the film thickness of a ferromagnetic metal layer forming a recording layer, as well as a production method thereof, and a magnetic recording device. The magnetic recording medium includes a ferromagnetic metal layer of a cobalt based alloy formed on a base material with a metal underlayer having chromium as a major constituent disposed there between, wherein a seed layer having at least tungsten is provided between the base material and the metal under-layer, and the seed layer is an islands type film.

Abstract: A perpendicular magnetic recording medium having a substrate, a seedlayer on the substrate and a magnetic underlayer on the seedlayer, the magnetic underlayer having an easy axis of magnetization substantially directed in a radial or transverse direction, and a process for manufacturing the perpendicular magnetic recording medium are disclosed.

Abstract: The subject invention related to methods and apparatuses for the manufacture of magnetizable carrier particles. In addition the subject invention pertains to particles having one or more of a variety of particle configurations and/or functional features. These geometric particle configurations and/or functional features such as delivering or removing a pay load can be tailored to achieve one or more desired missions. The subject invention also pertains to a method and apparatus for the delivery of particles to target materials, in order to accomplish one or more of a variety of missions. In a specific embodiment of the subject invention, acicular and other particles with a lengthwise dimension that are substantially uniform and homogenous in their geometry are manufactured and provided with magnetizations. In this way, predictable mechanical force responsivity can be achieved when these particles are subjected to an external magnetic field gradient.

Abstract: There are disclosed an information recording medium substrate having a surface roughness of Rmax 15 nm or less, and an information recording medium, particularly an information recording medium substrate and information recording medium in which for surfaces of the substrate and medium, a bearing area value (offset bearing area value) in a depth of 0.5 to 5 nm (predetermined slice level) from a bearing height (real peak height) corresponding to the bearing area value of 0.2% to 1.0% is 90% or less, and a manufacture method of the substrate and medium.

Abstract: A magnetic recording medium includes an underlayer of a nonmagnetic alloy containing chromium and titanium, a magnetic layer of a Co—Cr—Pt—Ta or Co—Cr—Pt—B alloy, and an intermediate layer of a Co—Cr—Pt alloy and being disposed between the underlayer and the magnetic layer, thereby carrying out high-density information recording and reproducing operation.

Abstract: An amorphous magnetic recording medium comprising a substrate and an amorphous magnetic layer, where a magnetic domain formation-controlling layer comprising a main phase and 1 to 3 kinds of discrete spherical isolating phases arranged horizontally in lines in the main phase or 1 to 3 kinds of discrete spherical phases vertically stacked one upon another in the main phase is formed on the top side or the bottom side directly or through at least one of other layers to bring the amorphous magnetic layer into a finer magnetic domain structure, can satisfy high density recording.

Abstract: A magnetic recording medium which has higher S/N and lower manufacturing cost includes a first underlayer including at least one of Co or Cu and P on a non-magnetic substrate, a second underlayer consisting of a non-magnetic material using Cr, and a magnetic layer on the second underlayer.

Abstract: A method for manufacturing an elastic roll is provided including winding at least one fiber bundle comprising of a plurality of fibers to form fiber layers onto a hardroll core, the fiber layers being formed to lie on top of one another, with a direction of winding of the fibers being essentially parallel to one another and at an angle to a peripheral direction of the roll core, wherein fiber layers lying on top of one another are wound alternately in an identical but opposite manner to form a cross-composite layer; winding a damping fiber layer with fiber bundles of a uniform angular position onto the cross-composite layer, with an angular position of these fiber bundles being substantially flatter, relative to a longitudinal axis of the roll, than the angular positions of the fiber bundles of the cross-composite layer; and winding another cross-composite layer again onto the damping fiber layer.

Abstract: In the metallic thin film magnetic recording medium having the magnetic layer formed on a main face of a nonmagnetic supporting body according to vacuum thin film formation technology, the thickness of the nonmagnetic supporting body is 5 &mgr;m or less, the thickness of the magnetic layer is 20 nm-100 nm and a lining layer 20 nm-200 am in thickness is formed of metal, non-metal or alloy of these materials or oxide compound thereof according to vacuum thin film formation technology. Light transmittance is 5% or less and permeating water vapor amount is 5 g/m2·day or less. The lining layer and the back layer are formed successively on a main face opposite to the magnetic layer formation face. The relative roughness factor (Ra) of the topmost surface of the lining layer formation face is 2-15 nm.

Abstract: A magnetic layer structure with a layer of cobalt-chromium-platinum-boron composite alloy containing 10% to 20% B in the magnetic layer. The useful magnetic properties of the magnetic layer structure are achieved by the incorporation of a nucleation layer prior to the deposition of the magnetic layer. The resultant magnetic layer structures have coercivity Hc values in between 2,000 and 5,000 Oe, grain sizes between 30 and 200 Angstroms and anisotropic crystallographic orientation with the c-axis of the cobalt-chromium-platinum-boron in the plane of the medium. These magnetic layer structures are suitable for magnetic data storage devices including magnetic disks.

Abstract: A method of recording information on and reproducing information from a magnetooptical recording medium which includes first and second magnetic layers. The method includes the step of projecting a light spot onto the medium. When reproducing information, the light spot is projected onto the medium from the side of the magnetic layer. In this method only a high temperature region of the second magnetic layer within a light spot projection portion is changed to a perpendicular magnetization film so that information recorded in the first magnetic layer is transferred to the perpendicular magnetization film of the second magnetic layer. In addition, information which is transferred to the second magnetic layer is detected by using reflected light from the medium which is subjected to the magneto-optic effect from the perpendicular magnetization film of the second magnetic layer.

Abstract: A Co-Pt based magnetic alloy which has been doped with a relatively high amount of nitrogen, e.g., or above 1 at. % is obtained having high coercivity, for example in the range of 1400 Oe or above, and an increased signal-to-noise ratio as compared to the same Co-Pt based alloy which has not been doped with nitrogen. The alloy is vacuum deposited, for example, by sputtering, and the nitrogen may be introduced from the sputtering gas or from the sputtering target. Other low-solubility elements providing the grain uniformity and isolation include: B, P, S, C, Si, As, Se and Te.