Matsushita Electric Industrial Co., Ltd.

Hokkaido University

Eiichi Hirota

Hiroshi Sakakima

Harufumi Senno

Mitsuo Satomi

Yukihiro Yanagiuchi

Yasunari Sugita

Koichi Mukasa

Kiyotaka Wasa

Yasuhiro Kawawake

Kazuhisa Sueoka

Makoto Sawamura

Tadashi Kawamata

Masatsugu Yamaguchi

Yukio Terada

Tsuneo Inoue

Noboru Nomura

Kazuo Yokoyama

Koichi Kugimiya

Shigeru Hayakawa

Takao Tohda

Toshihiro Mihara

Motonori Nakamura

Ryosho Nakane

Takashi Kawamata

A magnetic recording element is composed of a first magnetic film to generate spin vortex by an external magnetic field and a second magnetic film having a magnetization perpendicular to the surfaces thereof, and also an insulating layer to control (repress) a current through the magnetic recording element which is formed between the first magnetic film and the second magnetic film. A given external magnetic field is applied to the magnetic recording element, to generate a spin vortex in the first magnetic film and then, generate a vertical magnetization at the center of the spin vortex. Then, a given data is written on the vertical magnetization.

Magnetic recording element, magnetic memory, magnetic recording method, method for fabricating a magnetic recording element, and method for fabricating a magnetic memory

A scanning magnetism detector includes a probe made of a solid material formed of a single crystal having spin polarization and electrical conductivity properties. When the probe is brought into proximity with a magnetic substance, a surface condition of the magnetic substance can be detected by measuring tunnel current flow between the probe and the surface of the magnetic substance.

Scanning magnetism detector and probe

Exchange coupling film, magnetoresistance effect device, magnetoresistance effective head and method for producing exchange coupling film

In amorphous materials including at least one iron-transition metal of Fe, Co, and Ni, and at least one metalloid of B, C, Si, and P, excellent magnetic characteristics can be provided subject to the condition that 0.5 to 10 atomic % of the above-described iron-transition metals are substituted by Mn. In addition, when the amorphous material partially substituted with Mn as described above is further comprised of at least one element selected from Groups IIIa, IVa, Va, and VIa in the periodic table, the crystallization temperature is considerably raised.

Amorphous materials with improved properties

A magnetic head includes at least a core for constituting a magnetic circuit and a magnetic gap formed in the core. The core comprises an amorphous magnetic metallic film formed on a non-magnetic high-resistance substrate so that one of the end faces of the non-magnetic high-resistance substrate and the amorphous magnetic metallic film may be brought into contact with a magnetic recording medium.

Magnetic head incorporating an amorphous magnetic metallic film having a

A magnetic head and a method of producing same, wherein the magnetic head includes a head core formed of metallic magnetic material and has a head gap formed in a portion of the head core adapted to be positioned against a recording medium, and windings mounted on the head core. The material forming the head core is amorphous and has the following composition:

Magnetic head and method of producing same

Amorphous alloy consisting mainly of 60-94 atomic % of at least one transition metal, and over 2 atomic % but below 20 atomic % of niobium. The amorphous alloys according to the invention are high in wear resistance and corrosion resistance and have a high saturated magnetic flux density and soft magnetic properties. The amorphous alloys have particular utility as core materials for magnetic heads.

Amorphous magnetic alloys

Amorphous alloy films are heat-treated in the presence of a magnetic field directed in a particular direction so as to suppress induced magnetic anisotropy in the film. The directed magnetic field includes a vertical magnetic field whose direction is perpendicular to the plane of the film, and a rotating magnetic field whose direction is being rapidly changed within a parallel plane with respect to the plane of the amorphous alloy film.

Method for heat-treating amorphous alloy films

A method of heat treatments of amorphous alloy ribbons comprises the sequential steps of; grinding amorphous alloy ribbon continuously fed at a predetermined speed (V) selectively varied in the range of 1 cm/sec.ltoreq.V.ltoreq.50 cm/sec, to uniformly finish the ribbon, and successively, heat-treating the ribbon with its surface contacting a stationary or rotating heating body having a surface temperature (T) defined in the range of (T.sub.cry -200.degree. C.).ltoreq.V.ltoreq.(T.sub.cry +50.degree. C.), where T.sub.cry is a crystallization point temperature of the alloy, to uniformly enhance the magnetic properties of the ribbon, and to remove the specific curlings inherently caused by so-called splat cooling manufacturing method, without causing any developments of brittleness of the ribbon mentioned above.

Method of heat treatments of amorphous alloy ribbons

In a method of making a magnetic gap by depositing a glass layer on a surface of magnetic head core materials by cathodic sputtering of a glass target and cementing a pair of the resulting glass-coated magnetic head core materials, the improvements constituted by monitoring the thickness of the sputtered glass layer by an interference of a light beam guided onto a surface of the magnetic head core materials during the deposition and using a sputtering apparatus having a sample holder beside the target for securing the magnetic core materials and a mask plate for achieving uniform thickness of the sputtered glass layer. The method makes possible production of magnetic heads having excellent electromagnetic conversion characteristics with high accuracy.

Method of making a magnetic head

A method of making fibrous alkali titanates comprising the steps of preparing a mixture including a titanium compound and an alkali metal compound in a molar ratio of 1.0 to 8.0 in terms of TiO.sub.2 :M.sub.2 O (M: Na, K, Rb, Cs), heating said mixture at a temperature of 1200.degree. to 1600.degree. C to the molten (liquid) phase, cooling the thus heated mixture to room temperature , and washing the thus treated product. This method is advantageous because fibrous alkali titanates of large ratio of length to diameter can be easily produced in high yield.

Method of making fibrous alkali titanates

A method for producing, under a low pressure such as an ambient atmospheric pressure, a ferromagnetic chromium oxide having a sufficiently high saturation magnetization and, if necessary, sufficiently high coercive force as well. The main feature of this method is to use H.sub.2 O.sub.2 in conjunction with CrO.sub.3 and, if necessary, Te, Sb or an alkali element as well and to heat them.

Method for producing a ferromagnetic chromium oxide

The present invention provides a ferromagnetic chromium oxide powder having an additive of sulfur incorporated therewith, which powder has a lower curie temperature than that of pure chromium dioxide powder and a high saturation magnetization. Said powder has a composition in weight percent, consisting essentially of 61.90 to 57.22 percent of chromium and 0.0038 to 15.10 percent of sulfur. Moreover, the ferromagnetic chromium oxide powder having a combination of sulfur and further additives selected from tellurium, tin and antimony has a lower Curie temperature than that of pure chromium dioxide together with a high intrinsic coercive force and a high saturation magnetization. The particles of these powders are in a uniform acicular shape and are useful in magnetic recording media, especially for slave tapes in thermo-magnetic duplication.

Process for the preparation of sulfur modified ferromagnetic chromium

This invention provides a magnetic head constituted by a magnetic core having a winding wound thereon, the magnetic core being a ferrite body composed of crystallites which have (111)-crystallographic planes thereof oriented substantially parallel with each other. The ferrite body is a dense polycrystalline and has much improved wear characteristics. The method of manufacturing the polycrystalline ferrite body includes the steps of mixing starting materials which include an .alpha.-Fe.sub.2 O.sub.3 powder with particles having a thin disc shape and other compounds in the weight ratio of given ferrite composition, cold-pressing the mixture into a cold-pressed body by a uniaxial pressure and sintering the cold-pressed body into a solid body so that the crystallites of the sintered body have the (111) 111)-planes substantially oriented.

Growing community of inventors

Hirakata, Japan

Eiichi Hirota