Matsushita Electric Industrial Co., Ltd.

Kanegafuchi Kagaku Kogyo Kabushiki Kaisha

Other

Japan Atomic Energy Agency

Sun-nanotechnology Co., Ltd.

Shogo Nasu

Koji Saiki

Hiroshi Ryonai

Tsuguhiro Korenaga

Shinji Uchida

Toshio Fukazawa

Hiroyasu Tsuji

Junichiro Kamiya

Norimoto Nochi

Oji Koizumi

A radiation shielding material that is lighter and has lower installation restrictions than conventional methods, and that exhibits excellent shielding efficiency against radiation in the high energy region. The radiation shielding material comprises a complex containing a fibrous nanocarbon material, a primary radiation shielding particle, and a binder, wherein the fibrous nanocarbon material and the primary radiation shielding particle are dispersed in the binder.

Radiation-shielding material

A prism and an optical pickup employing such prism includes a parallel prism having a polarization beam splitter film and a reflection film. The polarization beam splitter film is formed on an angled plane of a glass material having an approximate parallelogram cross-section, and consists of a multi-layer film of a composite film made of Si and SiO.sub.2-x (x&lt;0.5) and multiple layers of multiple dielectric films. The reflection film is formed on an angled plane of the same glass material approximately parallel to the angled plane on which the polarization beam splitter film is formed, and consists of a multi-layer film of a composite film made of metal Si and oxide SiO.sub.2-x (x&lt;0.5) as a high refractive film and multiple layers of multiple dielectric films as a relatively low refractive film.

Composite prism and optical pickup using the same

A magnetic head is provided with a protective film of chromium nitride on its sliding surface. The film thickness is set to have no adverse effect upon the electromagnetic conversion characteristics of the head, and the film has sufficient wear resistance not only against a magnetic tape having its sliding surface formed of iron oxide or other metallic magnetic substances, but also against a magnetic tape having its sliding surface formed of chrome oxide, the chrome oxide substance having a strong abrasion effect upon the magnetic head. The protective film has a compressive internal stress in a range of 10.sup.9 to 10.sup.11 dynes/cm.sup.2, a Knoop hardness of not less than 1500 kgf/mm.sup.2, a nitrogen composition ratio in a range of 20 to 60 atom %. The magnetic head core portion (23, 60) or non-magnetosensitive portion (25; 26, 61) has a plurality of minute projections (62) formed on the top surface thereof. The height of each projection is approximately equal to the size of each crystalline particle in diameter of the core portion or the non-magnetosensitive portion, where the maximum surface roughness is made greater than 150 .ANG..

Magnetic head having chromium nitride protective film for use in

A magnetic head is provided with a protective film of chromium nitride on its sliding surface. The film thickness is set to have no adverse effect upon the electromagnetic conversion characteristics of the head, and the film has sufficient wear resistance not only against a magnetic tape having its sliding surface formed of iron oxide or other metallic magnetic substances, but also against a magnetic tape having its sliding surface formed of chrome oxide, the chrome oxide substance having a strong abrasion effect upon the magnetic head. The protective film has a compressive internal stress in a range of 10.sup.9 to 10.sup.11 dynes/cm.sup.2, a Knoop hardness of not less than 1500 kgf/mm.sup.2, a nitrogen composition ratio in a range of 20 to 60 atom %, and a film thickness in a range of 50 to 1000.ANG..

Magnetic head having a chromium nitride protective film for use in a

A magnetic recording medium is disclosed, wherein a magnetic film comprising a partially oxidized cobalt with its in-plane coercive force not less than 500 Oe is provided on a substrate. Further disclosed are megnetic recording media, wherein there is further provided an underlayer comprising Cr, Fe or an Fe-Co alloy under said magnetic film, and wherein a perpendicular magnetic anisotropic film comprising a partially oxidized metal is further provided on said magnetic film. The magnetic recording media of the present invention are high in recording density and reproduction output, low in noise and high in S/N ratio.

Magnetic recording medium having a Co-O magnetic layer, and specified

A perpendicular magnetic storage medium in which a perpendicular magnetic anisotropic film having an easy magnetization axis perpendicular to the plane thereof is formed on a substrate, wherein the perpendicular magnetic anisotropic film is a film of a sub-oxide of Fe-Co alloy, the sub-oxide has a half-value width not less than 0.7 degrees with respect to a diffracted X-ray peak caused by oxide phase observed in X-ray diffraction spectrum, and saturation magnetization in terms of 4.pi.Ms of the film is within a range from 6,000 Gauss to 13,000 Gauss. The medium has high recording/reproducing sensitivity, high recording density and high wear resistance, and can be produced easily and economically at a low substrate temperature.

Perpendicular magnetic storage medium

A perpendicular magnetic storage medium comprising a substrate and a perpendicular magnetic anisotropic film formed on the substrate, characterized in that the perpendicular magnetic anisotropic film is a film of a sub-oxide of a metal having a composition described by a general formula [(Fe.sub.1-x Co.sub.x).sub.1-y M.sub.y ].sub.1-z O.sub.z [where 0.01.ltoreq.x.ltoreq.0.75, 0.ltoreq.y.ltoreq.0.30, 0.05.ltoreq.z.ltoreq.0.50 and M means at least one metal excluding Fe and Co.); and has an easy magnetization axis being perpendicular to a plane thereof, and both a peak of diffracted X-ray intensity caused by oxidized Fe and a peak of diffracted X-ray intensity caused by metal state Fe and Co and Metal M observed in X-ray diffraction spectrum. The perpendicular magnetic storage medium of the present invention can be produced easily and economically at a low substrate temperature, and has high wear resistance, high recording/reproducing sensitivity and high recording density.

A perpendicular magnetic storage medium comprising a substrate and a perpendicular magnetic anisotropic film formed on the substrate, characterized in that the perpendicular magnetic anisotropic film is a film of a sub-oxide of a metal having a composition described by a general formula [(Fe.sub.1-x Co.sub.x).sub.1-y M.sub.y ].sub.1-z O.sub.z [where 0.01.ltoreq.x.ltoreq.0.75, 0.ltoreq.y.ltoreq.0.30, 0.05.ltoreq.z.ltoreq.0.50 and M means at least one metal excluding Fe and Co.]; and has an easy magnetization axis being perpendicular to a plane thereof, and both a peak of diffracted X-ray intensity caused by oxidized Fe and a peak of diffracted X-ray intensity caused by metal state Fe and Co and Metal M observed in X-ray diffraction spectrum. The perpendicular magnetic storage medium of the present invention can be produced easily and economically at a low substrate temperature, and has high wear resistance, high recording/reproducing sensitivity and high recording density.

Growing community of inventors

Kobe, Japan

Shogo Nasu