| 摘要 |
PURPOSE:To obtain a magnetic disk which has an excellent signal/noise ratio and is isotropic in a circumferential direction by providing a magnetic layer formed by dispersing magnetic powder into a binder on a primer layer having a specified thickness and surface roughness. CONSTITUTION:If a paint for coating of a primer layer is coated at an ordinary temp. to a solid concn. higher than 10%, more preferably 20% and the thickness of the dry coated film ranging from 1.0mum to 10mum, there are substantially no pores and therefore the surface smoothness of the primer layer has <=0.035mum surface roughness. Said primer layer is more preferably subjected to a calendering treatment after formation of said layer to compress and annihilate the pores so that the surface roughness is made <=0.030mum. If the resin incorporated therein with a polyurethane resin and crosslinking agent is used as the resin for the primer layer, the dissolution of the primer layer by the solvent in the magnetic paint and the consequent elution of the resin, etc. in the primer layer into the magnetic paint in the stage of coating the magnetic layer are substantially prevented.
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