Hitachi Maxell, Limited

Hirosuke Mikami

Hideo Fujiwara

Takeshi Tottori

Osamu Inagoya

Kazunari Nakagawa

A composite magnetic head having a recording/playback head and an erasing head combined in one unit through a nonmagnetic material is constructed such that at least one of two core halves constituting the erasing head adjacent to the recording and reproducing head is made of single crystal ferrite, a plane (100) of the single crystal ferrite is substantially parallel to a principal magnetic path-forming plane, and an angle .theta. between an orientation &lt;100&gt; existing in the plane (100) and an operating gap (magnetic gap)-forming plane is in the range of 10.degree.-40.degree. or 80.degree.-120.degree.. The composite magnetic head thus constructed can be made to have a reduced distance between magnetic gaps of both heads so as to be suited for being attached to the compact high-density recording and reproducing apparatus while eliminating crosstalk.

Composite magnetic head

A magnetic head for write and read of information, the core of which is at least in part composed of magnetic metal thin layers and non-magnetic intermediate metal oxide layers alternately laminated is provided. The metal is a cobalt base amorphous alloy or permalloy and the metal oxide is selected from SiO, Al.sub.2 O.sub.3, MgO and BaTiO.sub.3, which has a Vickers hardness of not less than 200 to less than 1,200. The use of the magnetic head does not injure a magnetic recording medium and contributes to improvement of the durability of the magnetic recording medium.

Magnetic head

In manufacturing a magnetic head having a magnetic circuit formed of magnetic material in which anisotropy can be induced, the magnetic head is processed by a first annealing process in a magnetic field for inducing anisotropy to generate an axis of easy magnetization in one direction in a part of the magnetic material, subsequently the magnetic head is processed by a second annealing process for annealing the magnetic material, applying the magnetic field in one of the directions perpendicular to the axis of the easy magnetization so as to relax the anisotropy induced by the first annealing process.

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Ibaraki, Japan

Hirosuke Mikami