| 摘要 |
PROBLEM TO BE SOLVED: To decrease the magnetic interaction among magnetic powder particles in a magnetic layer, to maintain the reproducing output and to decrease noise by incorporating a nonmagnetic powder into a magnetic layer with a specified proportion of the nonmagnetic powder to the sum amt. of the nonmagnetic powder and a ferromagnetic powder. SOLUTION: A magnetic layer 3 is formed on one surface of a nonmagnetic support 2. The magnetic layer 3 consists of a ferromagnetic powder and a nonmagnetic powder dispersed in a binder. As for the nonmagnetic powder in the magnetic layer, for example, titanium oxide of rutile or anatase, aluminum oxide and nonmagnetic iron oxide can be used, and iron oxide such asα-Fe2 O3 , iron oxyhydroxide such asα-FeOOH andγ-FeOOH are preferably used. The amt. of the nonmagnetic powder is controlled to between >=20 wt.% and <=80 wt.%. Thereby, the interaction among the ferromagnetic powder particles is suppressed and noise can be effectively suppressed.
|
