| 摘要 |
PURPOSE:To obtain a recording medium having high coercive force and residual magnetic flux density, a small characteristic change owing to a temp. change and good stability in recording magnetization by forming the medium in such a way that the rate of the change in the coercive force with temp. of a magnetic layer consisting essentially of a Co-Ni alloy and the compsn. of the magnetic layer satisfy the specific relation. CONSTITUTION:A thin magnetic alloy film layer 3 consisting essentially of Co1-xNix (0<=x<=0.5) is formed on a substrate 1 consisting of polyester, polyimide, glass or a metallic sheet such as Al sheet subjected to an oxidation treatment on the surface directly or after an underlying layer 2 consisting of non- magnetic metals which are metals such as Bi, Sb, Gs, Si, etc. or the alloys, intermetallic compds., etc. thereof is deposited thereon by evaporation. The content of Ni is so determined that the rate of change in the coercive force Hc with temp. of such magnetic layer 3 Y=Hc1/Hc2 (where Hc1 is the coercive force at 100 deg.C and Hc2 is the coercive force at -196 deg.C) satisfies the relation Y>=0.27+ 0.85x. The change in Br/Hc between the residual magnetic flux density Br and the coercive force Hc with temp. is thus decreased and the magnetic recording medium having high stability in recording magnetization with temp. is obtd.
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