VERTICAL MAGNETIC RECORDING MEDIUM

摘要

PURPOSE:To improve vertical orientation of a vertically magnetized layer and to improve recording density by forming a backing layer having high magnetic permeability on a nonmagnetic base plate by laminating alternately nonmagnetic films and high magnetic permeability layers into multiple layers on said base plate. CONSTITUTION:Plural layers of nonmagnetic films 21a consisting of Ti, etc. and ''Permalloy'' films 21b are laminated alternately on an Al base plate 1 subjected to an alumite treatment to form a backing layer 21 having high magnetic permeability. A Co-Cr vertically magnetized layer 3 is deposited thereon. Since the films 21b are thin, the growth of the coarser crystal grains is suppressed and the vertical orientation of the film 3 is improved. A high recording density is thus obtd.