FERROMAGNETIC METAL POWDER AND MAGNETIC RECORDING MEDIUM USING IT

PROBLEM TO BE SOLVED: To provide a ferromagnetic metal powder which is excellent in output, C/N ratio and overwrite characteristic in a short wavelength range, and low in demagnetization level and excellent in preservation stability even under a high temperature and high-humidity environment, and is used suitably in a high-density digital recording system, and a magnetic recording medium using it. SOLUTION: In ferromagnetic metal powder which consists of a metal part as a core section and an oxide layer which exists in circumference thereof, the ferromagnetic metal powder is characterized in that the oxide layer consists of two or more layers, and principal components of the oxide layer which forms a surface of the ferromagnetic metal powder is oxide and/or oxy-hydroxide of aluminum, and principal component of the second layer inside the surface being oxide and/or oxy-hydroxide of rare earth elements including Y. The magnetic recording medium has this powder in a magnetic layer with a thickness of 0.01-0.5 μm. COPYRIGHT: (C)2007,JPO&INPIT