Magnetic disc
AssigneeHitachi Maxell, Ltd.
InventorsTeruhisa Miyata, Akira Miyake, Masaya Funahashi
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Abstract
A magnetic disc comprising a non-magnetic substrate, an undercoat coated on the surfaces of the substrate and a magnetic layer containing magnetic powder dispersed in a binder coated on the undercoat, characterized in that the undercoat has a thickness of from 0.5 to 10.0 .mu.m and such a porosity that a lubricant is contained therein in an amount of from 30 to 200 mg/cm.sup.3, which provides good surface lubricity and improved durability.
Claims6
A magnetic disc comprising a non-magnetic substrate, at least one undercoat coated on at least one surface of said substrate and a magnetic layer containing magnetic powder dispersed in a binder coated on at least one said undercoats, said at least one undercoat comprising a resin and a fine powder in a weight ratio of 20:80 to 80:20 and optionally a cross linking agent having a thickness of from 0.5 to 10.0 .mu.m and such a porosity that a lubricant is contained therein in an amount of from 30 to 200 mg/cm.sup.3.
Dependencies are inferred from the claim text.