| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic recording medium which has both satisfactory heat stability and recording and reproducing characteristics by reducing exchange coupling in an in-plane direction of a substrate of a main recording layer and achieves high density recording and reproducing of information, its manufacturing method and a magnetic recording and reproducing device. SOLUTION: The perpendicular magnetic recording medium has at least a backing layer, an orientation control layer, a magnetic recording layer and a protective layer on a non-magnetic substrate, wherein the magnetic recording layer comprises two layers or more and includes a first magnetic recording layer and a second magnetic recording layer from the substrate side, and wherein magnetocrystalline anisotropic energy (K<SB>u</SB>) of the respective magnetic recording layers are 4×10<SP>6</SP>(erg/cc) or more in the first magnetic recording layer and 2×10<SP>6</SP>(erg/cc) or below in the second magnetic recording layer, and wherein the first magnetic recording layer is composed of a gain boundary part made of magnetic Co alloy crystal and oxide, and the area of the grain boundary part is equal to or more than 30% in plane TEM observation. COPYRIGHT: (C)2009,JPO&INPIT
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