Abstract: A magnetic recording medium having a first magnetic layer positioned on a substrate and a second magnetic layer positioned on the first magnetic layer, wherein the first magnetic layer is a film of a partial oxide based on Co in which a growth direction of crystalline grain is substantially normal to the film plane and the easy magnetization axis is in a direction of the film plane or direction substantially normal to the film plane, and the second magnetic layer is a film of a partial oxide based on Co in which the growth direction of crystalline grain is diagonally inclined to the line normal to the film plane and the easy magnetization axis is diagonally inclined to the line normal to the film plane.

Abstract: A magnetic recording medium fabrication device includes a cooling drum around which a substrate runs while being cooled thereby, an ion gun arranged upstream to a vapor deposition station for kicking out particles absorbed on the plane of the substrate, a cooling body arranged between the cooling drum and ion gun for absorbing kicked out particles and a vapor deposition means for depositing a magnetic layer on the substrate at the vapor deposition station. The magnetic particles forming the magnetic layer that have residual magnetization vectors within .+-.10.degree. of the easy axis direction including the magnetic anisotropy of the medium are greater than or equal to 70% and less than or equal to 90% of the total amount of magnetic particles.

Abstract: A magnetic tape having a polymer substrate and a magnetic layer which is formed directly on a surface of the substrate or on a primer layer formed on the substrate and contains cobalt, oxygen and optionally nickel, in which a coercive force is at least 120 kA/m and a squareness ratio is at least 0.

Abstract: In a manufacturing method of a magnetic recording medium with a vacuum deposition, two shielding members are provided above a substrate for defining an aperture. An evaporation source is located at a position wherein evaporated atoms from an evaporation material can adhere to a moving substrate through the aperture. The substrate is moved while a material in the evaporation source is irradiated at two evaporation portions with two electron beams along a moving direction of the substrate to form a magnetic layer. Thus, curving of columnar gains formed in the magnetic layer is suppressed or crystal orientation is enhanced, and magnetic read/write characteristics are improved. Further, a productivity is improved because the aperture can be enlarged than previously by using the two evaporation portions.

Abstract: A magnetic recording medium has a cobalt-based first magnetic layer and a cobalt-based second magnetic layer which are formed on a substrate of high polymer by vacuum evaporation. In order to have a high reproducing output and a high S/N ratio, the first magnetic layer has high oxygen density area which is arranged at a vicinity of the second magnetic layer, and the second magnetic layer has high oxygen density area which is arranged at a vicinity of the first magnetic layer.

Abstract: A magnetic recording medium having good high density recording characteristics is produced by forming a magnetic layer on a substrate which is traveling around a peripheral surface of a cylindrical can by an oblique vapor deposition method to form a magnetic layer comprising cobalt, an axis of easy magnetization of which inclined from a line normal to the layer plane. A residual gas pressure in an initial region of the formation of the magnetic layer is kept as low as possible, in particular, the residual gas pressure in the initial region of the formation of the magnetic layer is lower than in the other part of the production apparatus.

Abstract: A magnetic recording medium having good high density recording characteristics is produced by forming a magnetic layer on a substrate which is traveling around a peripheral surface of a cylindrical can by an oblique vapor deposition method to form a magnetic layer comprising cobalt, an axis of easy magnetization of which inclined from a line normal to the layer plane. A residual gas pressure in an initial region of the formation of the magnetic layer is kept as low as possible, in particular, the residual gas pressure in the initial region of the formation of the magnetic layer is lower than in the other part of the production apparatus.

Abstract: In a magnetic recording medium with a back coat layer including polyurethane having a Tg (glass-transition temperature) below room temperature, isocyanate hardener, carbon powder and inorganic abrasive pigment are formed on a face of a non-magnetic substrate opposite a face covered by a magnetic recording film. Using this back coat layer, improved post contact characteristics and the like are obtained and smooth running conditions under small tensions are realized. Further, the magnetic recording medium causes only a small amount of head wear, and the medium has improved wear resistance.

Abstract: A magnetic recording medium includes a nonmagnetic substrate and a magnetic layer which is formed on a surface of the substrate and which has an axis of easy magnetization inclined from a direction to normal plane of the layer. An angular dependency of coercive force, of the medium which is measured by changing an application angle of a magnetic field in a range relative to -90.degree. to +90.degree. from the plane of the layer with a plane normal to the layer and including the axis of easy magnetization, has two local maximum values and two local minimum values. A ratio of the local maximum value closer to a plane direction to the minimum value closer of the layer to the local plane direction of the layer is from 1.6 to 2.4, and the local maximum value closer to the plane direction of the layer is larger than the local maximum value closer to the line normal to of the plane of the layer. The medium has a high S/N ratio.

Abstract: A magnetic recording medium having a nonmagnetic substrate, a first magnetic layer which is formed on a surface of the substrate, has an axis of easy magnetization slanting from a normal line of a layer plane, contains cobalt and oxygen in an amount of not more than 40 atomic % and has a thickness of not larger than 0.15 .mu.m, and a second magnetic layer which is formed on a surface of the first magnetic layer, contains cobalt, has an axis of easy magnetization slanting from a normal line of a layer plane, contains oxygen in an amount of not larger than 37 atomic % and from 61 % to 99 % of the oxygen concentration in the first layer, and has a thickness of not larger than 0.15 .mu.m, which medium has a large S/N ratio.

Abstract: A method for producing a magnetic recording medium having a magnetic layer having a two-layered structure positioned on a substrate, which includes forming the magnetic layer on the substrate by a vacuum deposition process during the travel of the substrate on a cylindrical can, wherein a first evaporation source and a second evaporation source are positioned on the same side of a vertical line passing across a longitudinal axis of the cylindrical can while confronting the cylindrical can, a shield plate having a first opening and a second opening is positioned between the cylindrical can and the first and second evaporation sources, each of vapors evaporated from the first and second evaporation sources passes through the first and second openings, respectively, a distance between the vertical line passing across the longitudinal axis of the cylindrical can and a center of an evaporation part of the first evaporation source is longer than a radius of the cylindrical can, and a distance between the vertical l

Abstract: In the method for making the magnetic recording wherein a first magnetic layer is formed on a substrate and a second magnetic layer is formed on the first magnetic layer, before forming the second magnetic layer, accelerated ions are irradiated onto a surface of the first magnetic layer. Thereby, naturally formed oxidized layer and adhered impurity on the first magnetic layer are removed from the surface of the first magnetic layer by ion etching action by the irradiation of ions, and hence a preferable condition of an interface between the first magnetic layer and subsequently formed second magnetic layer is obtained.

Abstract: The method includes applying ions and electrons from an ion gun onto a polymer film while the polymer film is traveling circumferentially along a peripheral surface of a cylindrical can from a supply location to a take-up location of the polymer film relative to the cylindrical drum. The ions and electrons from the ion gun are applied onto a part of the polymer film while it is moving through a position near the supply location of the polymer film relative to the drum at which the polymer film begins to contact the outer peripheral surface of the drum. At a downstream location relative to the drum, electrons are applied from an electron gun onto the polymer film traveling on the drum surface. At a further downstream location relative to the drum, the thin film is deposited, e.g., by vacuum evaporation, on the polymer film travelling on the drum. This method enables a thin film, having no wrinkles and with a high adhesion strength with respect to the polymer film, to be produced in a stable manner.

Abstract: In manufacturing perpendicular magnetic recording medium wherein a magnetic layer containing Co and Cr as main contents on a running substrate of polymer film incident angle (.phi..sub.f) of vaporized atom to form said magnetic layer is 30.degree. or larger at the final part of the film formation to improve manufacturing capacity, and magnetic layer (119) is heated after forming the magnetic layer in an oxygen-containing atmosphere.

Abstract: A perpendicular magnetic recording method uses a perpendicular magnetic recording medium. This medium comprises a perpendicular anisotropy film having perpendicular remanent magnetization Mr and longitudinal remanent magnetization Mr.sub..parallel., wherein the value of the ratio Mr.sub..perp. /Mr.sub..parallel. is not less than 0.2, but is less than 1.

Abstract: A vertical magnetization recording medium is formed on a high polymer film substrate by vacuum deposition of Co-Cr film or deposition of Co-Cr film with preceding deposition of permalloy film, both with Ti-vacuum deposited interface film on the substrate face, whereby vertical orientation of the C-axis of Co-Cr film with respect to the film surface is easily obtainable, thereby assuring good characteristic as vertical magnetization recording medium.

Abstract: A vertical magnetic recording medium comprises a non-magnetic substrate, a permalloy film consisting of plural permalloy layers separated by at least one non-magnetic layer placed therein, each of said plurality of permalloy layers being 2000 .ANG. or less thick, and a Co-Cr vertical magnetization film formed on the permalloy film directly or through another non-magnetic layer.

Abstract: A magneto-resitive playback head and a recording and reproducing device for reproducing a recording signal from a double-layered film type perpendicular magnetic recording medium. The playback head includes a magneto-resistive element included in high-permeability thin films and having one end portion facing the recording medium. The magneto-resistive element exhibits a magneto-resistance effect responsive to magnetic fluxes generated from signal magnetization in the recording medium. The head also includes electrodes for supplying an electric current longitudinally of the magneto-resistive element, and high-permeability members for introducing the signal magnetic fluxes passed through the magneto-resistive element again to the recording medium. A magnetic recording and reproducing device comprises the playback head, a thin film magnetic recording head, a recording circuit, a playback circuit, and a driving circuit which gives a relative motion between the medium and the heads.

Abstract: A method for manufacturing a magnetic recording medium is proposed to determine an angle of incidence of vaporized atoms to be not more than 60.degree. at an initial period of formation of a magnetic film by the vapor deposition method on a substrate which is travelling. The magnetic film contains Co and Cr as major constituents and has an axis of easy magnetization normal to the surface thereof.

Abstract: In making magnetic recording media by vapor-depositing magnetic metal film containing Co-Cr with 70-90 weight % Co as host material on a high polymer substrate, with or without intermediate layer(s) inbetween, making the high polymer substrate run around a cylindrical can, condition is selected such that linear expansion coefficient of the substrate is 1.0.times.10.sup.-5 -2.9.times.10.sup.-5 /.degree.C. and temperature of the can surface is 150.degree.-300.degree. C.; thereby normal or inverse curling of the resultant recording medium is substantially eliminated.