COMPOSITE METAL MAGNETIC GRAIN POWDER AND MAGNETIC RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide metal magnetic grain powder having excellent preservation stability, further having excellent durability and surface smoothness and suitable as magnetic grain powder for a magnetic recording medium. SOLUTION: In the composite metal magnetic grain powder, the grain surfaces of the metal magnetic grain powder are subjected to surface treatment with phenylphosphonic acid and/or phenylphosphate. The metal magnetic grain powder contains Nd and Al. The magnetic recording medium contains the composite metal magnetic grain powder in a magnetic recording layer.