Magnetic recording medium
AssigneeFuji Photo Film Co., Ltd.
InventorsMasahiko Mori, Kiyomi Ejiri
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AssigneeFuji Photo Film Co., Ltd.
InventorsMasahiko Mori, Kiyomi Ejiri
Estimating the term…
Provided is a magnetic recording medium exhibiting high C/N ratio and suited to high-density magnetic recording, particularly, to reproduction with MR heads. The magnetic recording medium comprises a nonmagnetic powder and a binder and a magnetic layer comprising a ferromagnetic powder and a binder in this order on a flexible nonmagnetic support. The magnetic layer has an average thickness ranging from 0.02 to 0.2 μm, the ferromagnetic powder contained in the magnetic layer is a plate-shaped hexagonal ferrite ferromagnetic powder having an average plate diameter of 10 to 40 nm, the ratio of a volume of magnetic reversal to a volume of magnetic material particles is equal to or less than 3, the magnetic layer has a coercive force Hc equal to or higher than 159 kA/m, and components magnetically reversing in the magnetic field of 80 kA/m or less are less than 1 percent in the magnetization distribution of the magnetic layer.
A magnetic recording medium comprising a nonmagnetic powder and a binder and a magnetic layer comprising a ferromagnetic powder and a binder in this order on a flexible nonmagnetic support, wherein
A method of manufacturing a magnetic recording medium comprising a step in which a nonmagnetic layer coating liquid comprising a nonmagnetic powder and a binder and, over the nonmagnetic layer, a magnetic layer coating liquid comprising a ferromagnetic powder and a binder are coated on a nonmagnetic flexible support by a wet-on-wet (wet/wet) method, wherein the ratio of the viscosity of the magnetic layer coating liquid to the viscosity of the nonmagnetic layer coating liquid is equal to or less than 0.8 at a shear rate of 45,000 s−1.
Dependencies are inferred from the claim text.