Magnetic recording medium
AssigneeFuji Photo Film Co., Ltd.
InventorsHitoshi Noguchi, Shinji Saito, Hiroshi Ogawa
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AssigneeFuji Photo Film Co., Ltd.
InventorsHitoshi Noguchi, Shinji Saito, Hiroshi Ogawa
Estimating the term…
A magnetic recording medium having excellent electromagnetic characteristics and well adapted for video use, which comprises a non-magnetic support having provided thereon at least two magnetic layers each comprising a ferromagnetic powder and a binder resin, wherein the uppermost magnetic layer arranged farthest from the support contains a cobalt-containing iron oxide powder having an Fe.sup.2+ /Fe.sup.3+ mole ratio of 20/100 to 50/100 and a coercive force of 650 to 1,500 Oe, and at least one of said magnetic layers is a lower magnetic layer in contact with the uppermost magnetic layer and contains a cobalt-containing iron oxide powder having an Fe.sup.2+ /Fe.sup.3+ mole ratio of less than 20/100 and a coercive force of 0.6 to 1.0 times that of the cobalt-containing iron oxide powder contained in the uppermost magnetic layer.
A magnetic recording medium comprising a non-magnetic support having thereon at least two magnetic layers, wherein said at least two magnetic layers comprise a ferromagnetic powder and a binder resin;
A method for recording video and audio signals having both good reproduced video output and print-through characteristics, comprising the steps of passing a magnetic recording medium through the fringing field above the gap of a magnetic head, said magnetic recording medium comprising a non-magnetic support having provided thereon at least two magnetic layers, said at least two magnetic layers containing a ferromagnetic powder and a binder resin, the uppermost magnetic layer arranged farthest from the support contains a cobalt-containing iron oxide powder having an Fe.sup.2+ /Fe.sup.3+ mole ratio of 20/100 to 50/100 and a coercive force of 650 to 1,500 Oe, and at least one of said magnetic layers is a lower magnetic layer in contact with said uppermost magnetic layer and contains a cobalt-containing iron oxide powder having an Fe.sup.2+ /Fe.sup.3+ mole ratio of less than 20/100 and a coercive force of 0.6 to 1.0 times that of the cobalt-containing iron oxide powder contained in the uppermost magnetic layer.
Dependencies are inferred from the claim text.