MAGNETIC RECORDING MEDIUM AND ITS PRODUCTION

摘要

PURPOSE: To obtain a magnetic recording medium which is good in yield in spite of a coating type, exhibits the reproduced output of a high-frequency region equiv. to that of a vapor deposited tape and has good surface roughness, good electromagnetic conversion characteristics, such as C/N and excellent traveling durability. CONSTITUTION: This magnetic recording medium has at least two layers formed by providing the surface of a flexible base with a lower nonmagnetic layer contg. nonmagnetic powder and binder and providing the surface thereof with an upper magnetic layer contg. ferromagnetic powder and binder while the lower nonmagnetic layer is still wet. The average value (d) of the dry thickness of the upper magnetic layer is <=1μm and the ferromagnetic powder incorporated into this layer is acicular ferromagnetic powder. The nonmagnetic powder incorporated into the lower nonmagnetic layer is inorg. powder having Mohs' hardness of >=3. The average grain size thereof is 1/2 to 4 times the crystallized size of the acicular ferromagnetic powder included in the upper magnetic layer.