| 摘要 |
PURPOSE:To suppress the deterioration of recording/reproducing characteristics in a high frequency region, by laminating core thin plates which are blanked from the side opposite to the insulating film forming surface of a magnetic thin plate. CONSTITUTION:An insulated film is formed on a single side of a magnetic thin plate before core thin plates 1 are press-cut out of a magnetic thin plate by using an electrophoresis process, etc. to stick aluminum oxide powder and cellulose, for example, in 3-4mum thickness. Then the magnetic thin plate containing the insulated coat, i.e., an insulated layer 2 is press-cut from the side opposite to the surface where the layer 2 is formed. Thus a U-shaped core thin plate 1 is obtained. This plate 1 is supplied with magnetic annealing in an hydrogen gas of about 1,100 deg.C, and then epoxy resin, etc. is coated on the plate 1. A prescribed number of plates 1 are laminated to form a core laminated product 5. For the lamination 5, the forming surfaces of layers 2 are set in a single direction. Thus the insulation is secured between the plates 1 and therefore reduces the impedance variation in a high frequency region. |
