MAGNETIC RECORDING MEDIUM
PURPOSE:To improve an S/N and a travelling performance, eliminate the filling of the, avoid the degradation of a saturated flux density during a storage period, etc., by a method wherein the respective materials of a first magnetic layer and a second magnetic layer which are formed on a substrate ar...
Gespeichert in:
Hauptverfasser: | , , |
---|---|
Format: | Patent |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext bestellen |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | PURPOSE:To improve an S/N and a travelling performance, eliminate the filling of the, avoid the degradation of a saturated flux density during a storage period, etc., by a method wherein the respective materials of a first magnetic layer and a second magnetic layer which are formed on a substrate are specified. CONSTITUTION:A magnetic layer formed on a substrate has a double-layer structure composed of an upper layer and a lower layer. The lower first layer is made of metal powder. Iron powder whose main component is iron or powder of alloy such as iron/cobalt, iron/nickel, etc., is used as the metal powder. The average long axis particle diameter and the axis ratio of the metal powder are not specifically limited. The coercive force of the metal powder is selected to be 500-1300Oe and smaller than the coercive force of the material of the upper second magnetic layer. The upper second magnetic layer is made of cobalt-coated iron oxide whose coercive force is not smaller than 1300Oe, preferably 1300-2000Oe, whose average particle diameter is not limited but average long axis length is 0.01-0.1mum and short axis length is 0.01-0.1mum and which has a needle-shape. If the coercive force of the second layer material is smaller than 1300Oe, a high output can not be obtained. |
---|