Data storage device, apparatus and method for using same

摘要

Data storage device for use as a portable card, magnetically encodeable card, or magnetic credit card, including a substrate having at least one surface. A high density, magnetically coercive material layer is disposed/deposited on the substrate for storing magnetic signals. The magnetically coercive material may have an axis of magnetization that is oriented in a predetermined direction relative to a surface of the substrate. A layer of non-magnetically material is disposed on the substrate for defining an exchange break layer. A protective coating is formed on the magnetic material layer and has a thickness between a maximum thickness which would materially attenuate magnetic signals passing between the magnetic material layer and a transducer and a minimum thickness enabling the protective coating to be abraded by usage in an ambient natural atmosphere operating environment. The protective coating may comprise one or more layers.