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:
Jul. 05, 1994
Filed:
Mar. 26, 1992
Katsumi Ryoke, Kanagawa, JP;
Yutaka Kakuishi, Kanagawa, JP;
Toshiyuki Kitahara, Kanagawa, JP;
Akihiro Matsufuji, Kanagawa, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A magnetic recording medium is described comprising a nonmagnetic support having formed thereon a magnetic layer containing a ferromagnetic powder, an abrasive, and a binder, wherein the ferromagnetic powder is a metal magnetic powder having a crystallite size of not larger than 200 .ANG., the abrasive comprises (i) an inorganic powder having a Mohs' hardness of more than 9 and a mean particle size of 0.1 to 0.9 .mu.m which is contained in an amount of from 0.1 to 10 parts by weight per 100 parts by weight of the ferromagnetic powder, and a center-line average surface roughness (Ra) of the magnetic layer is less than 5 nm. The magnetic recording medium exhibits improved properties in C/N, running durability and drop-out. A process of producing the recording medium is also disclosed involving a calender treatment with at least one pair of metal rolls.