Secondary agglomerates of magnetic metal particles for magnetic recording and process for producing the same

摘要

Secondary agglomerates of magnetic metal particles for magnetic recording, have a sodium content of not more than 20 ppm and a calcium content of not more than 40 ppm, an average particle diameter of 300 to 800 mu m and an upper limit of particle diameters of 2,000 mu m and comprise magnetic metal primary particles having an average major axis diameter of 0.05 to 0.25 mu m.