Ube Industries, Inc.

Iwao Okamoto

Ryoji Sugise

Kyoji Ohdan

Motozo Yoshikiyo

Atsushi Kajima

Kazuo Inoue

Toshitaka Fujii

Shizuka Yoshii

An electromagnetic effect material comprising xA-yB-zC-wD-.alpha.0 series oxide ceramics, in which A and B represent one or more of element selected from the combination of elements represented by the general formula ABO.sub.3 and capable of forming a perovskite structure material exhibiting a ferromagnetic or antiferromagnetic property, C and D represent one or more of elements selected from the combination of elements represented by the general formula CDO.sub.3 and capable of forming a perovskite structure material exhibiting a ferroelectric, antiferroelectric or piezo-electric effect, with a proviso of excluding a case in which A and C are identical and B and D are identical to each other and a case in which A is Bi and B is Fe, x, y, z and w represent the ratio for the elements A, B, C and D, respectively, x+y+z+w=1, 0.01&lt;x&lt;0.95, 0.01&lt;y&lt; 0.95, 0.01&lt;z&lt;0.95, 0.01&lt;w&lt;0.95 and .alpha. represents a number of oxygen atoms capable of satisfying atomic valence of other elements, and having a temperature region in which the electromagnetic bonding coefficient is greater than 1.0.times.10.sup.-5 (emu cm/V g) within a temperature range from 250 to 700K.

Electromagnetic effect material

A vertical magnetic recording medium excellent in durability and recording property in which a first magnetic film comprising Co--Cr or Co--Cr--W as the main ingredient is formed on a substrate and the second magnetic film comprising Co--Cr--W--C as the main ingredient is formed on the first magnetic film, as well as the production process therefor are provided.

Vertical magnetic recording medium and method of manufacturing the same

Growing community of inventors

Yamaguchi, Japan

Iwao Okamoto