| 摘要 |
PURPOSE:To perform the recording/reproducing of high reliability by fixing a magnetic disc to the center core which is fixed to about the center part of a flexible sheet like magnetic disc at the other part excluding the prescribed part of the outer peripheral edge side thereof. CONSTITUTION:The adhesive layer 3 fixing a magnetic material part 2B and magnetic disc 1 is provided only in the zone of good dimensional accuracy at the outer peripheral edge of the magnetic material part 2B without forming on the whole surface of the magnetic material part 2B. Namely the magnetic material 2B is formed within the range corresponding to the fitting face 4A on the upper face at the outer peripheral edge of a spindle 4. The magnetic material part 2B is set within the range that the radius which is measured from the rotary shaft upto the outer periphery of the adhesive layer 3 is R1 or Ra, in case of the radius from the rotary shaft upto the outside of the fitting face 4A of the spindle 4 being taken as R2 and the radius upto the inside of the fitting face 4A R1. In this way the magnetic disc 1 is not inclined along the magnetic material part 2B even in case of the plane at the outer peripheral part of the magnetic material part 2B being no good.
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