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:
Apr. 15, 1986
Filed:
Aug. 09, 1984
Takahito Miyoshi, Kanagawa, JP;
Kenichi Masuyama, Kanagawa, JP;
Masahiro Utumi, Kanagawa, JP;
Toshimitu Okutu, Kanagawa, JP;
Masaaki Fujiyama, Kanagawa, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A magnetic recording medium which comprises a non-magnetic support having on the surface side thereof a magnetic recording layer and on the opposite side thereof a backing layer having a thickness of 2 .mu.m or less, which contains carbon black and a binder and optionally, an inorganic powder, in which the backing layer contains at least two kinds of carbon black, one being fine-grained carbon black having a mean grain size of 10 to 30 m.mu. and the other being coarse-grained carbon black having a mean grain size of 150 to 500 m.mu. such that the weight ratio (P/B) of the total amount of carbon black and inorganic powder (P) to binder (B) is from about 1/0.5 to 1/3.5. The recording medium described provided smooth and stable tape-running for an extended period and a high S/N ratio.