Stock material or miscellaneous articles – Composite – Of inorganic material
Reexamination Certificate
2005-01-25
2005-01-25
Rickman, Holly (Department: 1773)
Stock material or miscellaneous articles
Composite
Of inorganic material
C428S690000, C428S690000, C428S667000, C428S900000, C428S611000
Reexamination Certificate
active
06846583
ABSTRACT:
A magnetic recording medium comprises a magnetic recording layer63which is formed by using an ordered alloy containing B on a substrate1containing an amorphous component. A part of B in the ordered alloy is segregated in a grain boundary, and thus the magnetic interaction, which acts between magnetic grains, can be reduced. Accordingly, it is possible to form fine and minute magnetic domains in the magnetic recording layer63, and it is possible to reduce the medium noise as well. The temperature, at which the substrate is heated during the film formation of the magnetic recording layer63, can be suppressed to be low, because the ordering temperature for the ordered alloy containing B is lower than those of ordered alloys not containing B. Therefore, it is possible to use a substrate made of glass which is suitable for the mass production. The magnetic recording layer63is also excellent in thermal stability because of the use of the ordered alloy having high magnetic anisotropy. According to the present invention, it is possible to provide the magnetic recording medium for high density recording which is excellent in thermal stability and which involves low medium noise.
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Fujita Enji
Inaba Nobuyuki
Kouda Tetsunori
Matsunuma Satoshi
Yamanaka Hideaki
Hitachi Maxell Ltd.
Oliff & Berridg,e PLC
Rickman Holly
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