Patent ID: 6309479
Filing Date: 2001-10-30
Classification: B82Y,C01G,C01P,G11B

Abstract:
Magnetic spindle-shaped metal particles containing iron as a main component, which contain cobalt of 8 to 45 atm %, calculated as Co, based on whole Fe, aluminum of 5 to 20 atm %, calculated as Al, based on whole Fe, and a rare earth element of 1 to 15 atm %, calculated as rare earth element, based on whole Fe; andhave an average major axial diameter of 0.05 to 0.15 .mu.m, an average minor axial diameter of 0.010 to 0.022 .mu.m, an aspect ratio (average major axial diameter/average minor axial diameter) of 4:1 to 8:1, a particle size distribution (standard deviation/average major axial diameter) of not more than 0.20, and an X-ray crystallite size D110 of 12.0 to 17.0 nm.