| 摘要 |
PURPOSE:To obtain the titled magnetic recording medium having excellent weather resistance and reliability by forming a Cr film on a metallic magnetic film with physical vapor deposition, further depositing a protective film thereon and allowing an active metallic Cr atom to remain in the Cr film layer. CONSTITUTION:A Cr film is coated on a metallic magnetic film 3 by sputtering with a PVD method (physical vapor deposition) wherein the partial pressure of Ar is regulated, for example, to 1-40mtorr and a protective film 5 is formed thereon. At this time, the Cr atom is not converted into a compd., etc., and allowed to remain in the layer as an active Cr atom layer having 5mm film thickness. Consequently, even when a defective part (uncoated part) is present in the thin Cr protective film 5 and water, etc., intrudes into the part to corrode the metallic magnetic film 3, Cr hydroxide, etc., is formed by the formation of a galvanic couple between the metallic magnetic film having a noble electrode potential and the active Cr film having a base electrode potential. Consequently, excellent corrosion resistance can be obtained by the coating of the magnetic film 3. Accordingly, even when the weather resistant protective film 5 is thin, the weather resistance can be improved and the high-density recording can be carried out.
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