MAGNETIC RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide a high density magnetic recording medium which has both the excellent electromagnetic conversion characteristics and the excellent running durability under a low temperature and a low humidity. SOLUTION: A recording medium has a supporter 2, a magnetic or nonmagnetic intermediate layer 3 formed on the supporter 2 and a magnetic layer 4 as an uppermost layer. The thicknesses of the intermediate layer 3 and the magnetic layer 4 is 0.3-3.0μm and 0.1-0.5μm respectively and the ratio of the thicknesses (former/latter) is 1/20-3/10. The magnetic layer contains ferromagnetic powder and carbon black. The ferromagnetic powder is needle-shaped metallic magnetic powder which contains aluminum in the powder surface layers and whose average long axes are 0.5-0.15μm. The peak value of the fine hole diameter distribution of fine holes existing in the surface of the magnetic layer is 5.5-11 nm.