| 摘要 |
PURPOSE:To obtain a disk having high performance with low modulation by setting plural rod magnets alternately, obliquely and reversely with each other in the shift direction of a supporter together with the random orientation of magnetic powder when a magnetic layer is formed on a belt-shaped magnetic supporter by a coating process. CONSTITUTION:For production of a flexible magnetic disk, a sheet, etc., a belt-shaped supporter 12 of polyethylene phthalate, etc. is shifted toward an arrow head A from a feed roll 11 and taken up to a take-up roll 14. At the same time, a magnetic coating liquid 16 is applied to the supporter 12 through a coating head 15 for formation of a coating film 16'. Here the 1st and 2nd rod type orientation magnets 17 and 18 are set under the supporter 12 so that they are oblique, alternate and reverse to each other toward the direction A with the magnetic poles set different from each other at the side toward the supporter 12. In this case, the magnetic field intensity of both magnets produced in the direction A is set at <=50Oe respectively. Thus the magnetic particles are orientated at random assuredly. This can prevent the modulation with which the reproduction output of the coating direction is higher than other directions when a disk obtained by cutting the supporter 12 containing a magnetic layer is reproduced.
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