The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 11, 1977
Filed:
Jul. 31, 1975
Goro Akashi, Odawara, JA;
Masaaki Fujiyama, Odawara, JA;
Nobutaka Yamaguchi, Odawara, JA;
Satoru Takayama, Odawara, JA;
Koji Sasazawa, Odawara, JA;
Fuji Photo Film Co., Ltd., Minami-ashigara, JA;
Abstract
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.