MAGNETIC RECORDING MEDIUM AND ITS PRODUCTION

摘要

PURPOSE:To enable good high-density recording by specifying the degree of orientation of the axis of easy magnetization in the direction perpendicular to the surface of the magnetic layer of magnetic powder to be incorporated into the magnetic layer to the value higher than 0.60 in the value measured by a Moessbauer method. CONSTITUTION:A vertical orientation magnetic field having the gradient stronger on a substrate side than the magnetic layer surface side is impressed to the magnetic layer to increase the degree of orientation of the axis of easy magnetization in the direction perpendicular to the magnetic layer surface of the magnetic powder to the value higher than 0.60 in the value measured by the Moessbauer method. The impression of the vertical orientation magnetic field having the gradient stronger on the substrate side to the magnetic coating compd. is executed by a method for disposing opposed N-S magnets or opposed N-S electromagnets for which solenoids are used near a coater for coating the magnetic coating compd. or magnetizing the coater itself, disposing a magnet opposed thereto near the coater and acting the vertical orientation magnetic field. The surface smoothness of the magnetic layer is thereby improved and the electromagnetic conversion characteristic is improved. The magnetic layer suitable for high-density recording is thus obtd.