| 摘要 |
PROBLEM TO BE SOLVED: To obtain platy magnet plumbite ferrite particles and powder which can have high blackness even when no F2+ is added to them and have a low volume resistivity value. SOLUTION: Platy magnet plumbite ferrite particles and powder for magnetic recording medium are coated with an organosilane compound produced from alcoxysilane, and very fine carbon black powder having an average particle diameter of 0.002-0.05 μm is stuck to the organosilane compound coatings. Therefore, the average particle diameter of the particles and powder become 0.01-0.2 μm. The ratio of the very fine carbon black powder sticking to the organosilane compound coatings to to 100 wt.% ferrite particles and powder is adjusted to 0.5-10 wt.%. |
