MAGNETIC POWDER AND MANUFACTURE THEREOF, MAGNETIC RECORDING MEDIUM BY USE THEREOF, AND RECORDING/ REPRODUCING METHOD AND DEVICE THEREOF

摘要

PURPOSE: To provide a magnetic recording medium where data that are stored once can not be erased and to provide a recording/reproducing method and a recording/reproducing device using the magnetic recording medium by a method wherein MnBi magnetic powder hardly deteriorating in saturation magnetization and excellent in corrosion resistance is used. CONSTITUTION: MnBi magnetic powder is manufactured through such a method that Mn powder and Bi powder both of grain diameter 50 to 300 mesh are mixed together, wherein the mol ratio of Mn content to Bi content of the mixed powder is previously set to 45:55 to 65:35, the mixture is press-molded, and the molded body is heated at temperatures lower than the fusing point of Bi in a non-oxidizing or a reducing atmosphere, whereby a reaction takes place to produce MnBi magnetic powder. A magnetic recording medium is formed of the manufactured MnBi magnetic powder, and a recording/reproducing method and a recording/reproducing device using the magnetic recording medium are obtained.