Magnetic recording medium
AssigneeVictor Company of Japan, Ltd.
InventorsYoshiteru Matsubayashi, Hiroto Nagamine
Life of this patent
Estimating the term…
Abstract
A magnetic recording medium of a coated type being formed by coating magnetic paint, which is mixed with and dispersed by a magnetic powder and a resin and an additive, on a substrate, the magnetic powder comprises a magnetite (Fe3O4) powder of which a surface is stuck with powdered carbon black, wherein a sticking amount of the powdered carbon black is within a range of 1 to 20 weight % per the magnetite powder.
Claims5
A magnetic recording medium of a coated type being formed by coating magnetic paint, which is mixed with and dispersed by a magnetic powder and a resin and an additive, on a substrate, said magnetic powder comprising magnetite (Fe3O4) powder of which a surface is stuck with powdered carbon black, wherein a sticking amount of said powdered carbon black is within a range of 1 to 20 weight % per said magnetite powder.
A magnetic recording medium of a coated type being formed by coating magnetic paint, which is mixed with and dispersed by a magnetic powder and a resin and an additive, on a substrate, said magnetic powder comprising magnetite (Fe3O4) powder of which a surface is stuck with powdered carbon black, wherein a sticking amount of said powdered carbon black is within a range of 3 to 15 weight % per said magnetite powder, and wherein a BET (Brunauer-Emmett-Teller) value of said magnetic powder is within a range of 25 to 45 m2/g, and wherein an absorbing amount of myristic acid of said magnetic powder is within a range of 8 to 25 mg/g.
A magnetic recording medium of a coated type being formed by coating magnetic paint, which is mixed with and dispersed by a magnetic powder and a binder and an additive, on a substrate, said magnetic powder comprising magnetite (Fe3O4) powder of which a surface is stuck with powdered carbon black, wherein a sticking amount of said powdered carbon black is within a range of 1 to 20 weight % per said magnetite powder, said binder comprising a polyurethane resin, which contains metal sulfonate group and tertiary amine.
A magnetic recording medium of a coated type being formed by coating magnetic paint, which is mixed with and dispersed by a magnetic powder and a binder and an additive, on a substrate, said magnetic powder comprising magnetite (Fe3O4) powder of which a surface is stuck with powdered carbon black, wherein a sticking amount of said powdered carbon black is within a range of 3 to 15 weight % per said magnetite powder and a pH of said powdered carbon black is less than 4, and wherein a BET value of said magnetic powder is within a range of 25 to 45 m2/g.
Dependencies are inferred from the claim text.