Dual-surface flexible magnetic tape

Abstract

A flexible magnetic-tape substrate is coated on both sides with an underlayer of relatively-low coercivity magnetic medium, which in turn is coated with a submicron layer of chromium dioxide in ultra small particles having a high coercivity. For longitudinal magnetic recording systems, magnetic layers with a coercivity of at least 1,500 Oe with underlayers having a coercivity between 25 and 500 Oe are used. For helical magnetic recording systems, magnetic layers with a coercivity of at least 2,000 Oe with underlayers having a coercivity between 25 and 800 Oe are used. These properties greatly reduce the effects of neighboring magnetic fields, thereby improving signal retention and virtually eliminating print-through and contact recording.

1 . A magnetic recording medium comprising: 
 a support substrate including a first layer of magnetic material on a first side and a second layer of magnetic material on a second side; and    a third layer of magnetic material coated onto said first layer; and    wherein said first layer has a coercivity smaller than about 800 Oe, and said third layer has a coercivity greater than about 1,500 Oe.