| 摘要 |
PURPOSE:To obtain a magnetic recording medium having high coercive force by forming a magnetic layer on a substrate and magnetizing the magnetic layer in a prescribed direction then subjecting the same to a heat treatment under the condition enough for induction magnetic anisotropy to saturate in a prescribed direction. CONSTITUTION:A substrate of polyethylene terephthalate having 16mum thickness is prepd. and Fe is vapor-deposited diagonally by evaporation at an incident angle of 80 deg. on the substrate to form a 1,000Angstrom vapor-deposited layer. Co is thereafter deposited by evaporation on the vapor-deposited layer of Fe from above at an amt. equiv. to 500 deg. in an oxygen atmosphere kept at 10<-3>Torr. The incident angle is 40Angstrom . The vapor-deposited layer obtd. in the above-mentioned way is magnetized in 1,000 Oe magnetic field along the prescribed direction in the plane thereof and is left standing for 5 days in the external magnetic field kept at 0, i.e., in the stage of residual magnetization. The layer is treated for one hour at 100 deg.C in an atmosphere kept at 25 deg.C and 60% RH (relative humidity) or by using a dryer. While the coercive force prior to magnetization at 1,000 Oe is 850 Oe, the magnetic recording medium having finally 2,200 Oe is obtd. in this embodiment. |
