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US 4,002,804 AGranted
Magnetic recording material
AssigneeFuji Photo Film Co., Ltd.
InventorsGoro Akashi, Masaaki Fujiyama, Nobutaka Yamaguchi, Satoru Takayama, Koji Sasazawa
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AssigneeFuji Photo Film Co., Ltd.
InventorsGoro Akashi, Masaaki Fujiyama, Nobutaka Yamaguchi, Satoru Takayama, Koji Sasazawa
Estimating the term…
A magnetic recording material which comprises a support having thereon a magnetic recording layer comprising a ferromagnetic substance and a binder, wherein the ferromagnetic substance comprises a mixture of (1) a Berthollide iron oxide having a particle size of about 0.5 .mu. or larger and a degree of oxidation represented by the value of x in FeO.sub.x of 1.33<x.ltoreq.1.45 and (2) a Berthollide iron oxide having a particle size of about 0.4 .mu. or smaller and a degree of oxidation represented by the value of x in FeO.sub.x of 1.43.ltoreq. x< 1.50, in which the weight ratio of Berthollide iron oxide (1) to Berthollide iron oxide (2) ranges from about 1:4 to 4:1.
A magnetic recording material which comprises a support having thereon a magnetic recording layer consisting essentially of a ferromagnetic material and a binder, wherein the ferromagnetic material is a mixture of (1) a Berthollide iron oxide having a particle size of about 0.5 .mu. or larger and a degree of oxidation represented by the value of x in FeO.sub.x of 1.33 <
In a magnetic recording material which comprises a support having thereon a magnetic recording layer, the improvement which comprises a ferromagnetic material which is a mixture of (1) a Berthollide iron oxide having a particle size of about 0.5.mu. or larger and a degree of oxidation represented by the value of x in FeO.sub.x of 1.33 <
Dependencies are inferred from the claim text.