| 摘要 |
PROBLEM TO BE SOLVED: To suppress transfer of a back layer to the surface of a magnetic layer, to reduce signal defect and irregular noise even if a magnetic body consisting of fine particles is used and to obtain satisfactory running stability, in high density recording. SOLUTION: The magnetic recording medium having the magnetic layer containing ferromagnetic powder having 1,000-10,000 nm<3> primary particle volume and a bonding agent on a substrate and the back layer containing non- magnetic powder and a bonding agent provided on the side opposite to the magnetic layer of the substrate is characterized in that the number PN (100-200 nm) of protrusions existing on a back surface and having 100-200 nm height measured by an atomic force microscope is 50-3,000 pieces/100μm square, protrusion existing ratio of the number PN (100-200 nm) of the protrusions is 2-60% to the number PN (total) of total protrusions per 100μm square and the number PN (>=200 nm) of protrusions having >=200 nm height is <=10 pieces/100μm square.
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