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:
Oct. 29, 1991
Filed:
Jul. 21, 1989
Takao Ohya, Kanagawa, JP;
Jun Nakagawa, Kanagawa, JP;
Satoru Hayakawa, Kanagawa, JP;
Yasuo Nishikawa, Kanagawa, JP;
Tsutomu Okita, Kanagawa, JP;
Hiroshi Hashimoto, Kanagawa, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A magnetic recording medium is disclosed, which comprises a non-magnetic support having provided thereon a magnetic layer mainly composed of a ferromagnetic powder and a binder resin comprising (i) a polymer having at least one polar group selected from --SO.sub.3 M.sup.1, --OSO.sub.3 M.sup.1, --COOM.sup.1, ##STR1## wherein M.sup.1 represents a hydrogen atom, Li, Na or NR.sub.4 (wherein R represents a hydrogen atom, an alkyl group, an alkenyl group, or an alkanol group), and M.sup.2 represents a hydrogen atom, Li, Na, an alkyl group, or NR.sub.4 (wherein R has the same significance as defined above); or (ii) a compound having at least one polar group selected from --SO.sub.3 M.sup.3, --COOM.sup.3, and --PO.sub.3 (M.sup.3).sub.2 (wherein M.sup.3 represents a hydrogen atom, an alkali metal, or an ammonium group) and containing at least one carbon-carbon unsaturated bond in the molecule, said magnetic layer containing at least one ester compound represented by following formula (I), (II), or (III), and when the binder resin comprises the compound (ii), the magnetic layer is irradiated by radiations: ##STR2## wherein R.sup.1 represents a straight chain or branched alkyl group having from 7 to 29 carbon atoms or a straight chain or branched alkenyl group having from 7 to 29 carbon atoms; l, k, m, and n represents an integer; l and n each is at least 2, and the sum of n and m and the sum of k and l are from 7 to 33.