Fuji Photo Film Company, Limited

Hideomi Watanabe

Tsutomu Okita

Hiroshi Hashimoto

Toshio Ishida

Akihiro Matsufuji

Yasuo Nishikawa

Masaki Satake

Takahito Miyoshi

Katsumi Ryoke

Nobuo Tsuji

Tadashi Yasunaga

Masashi Aonuma

Kazuyuki Usuki

Kazuko Hanai

Akira Ushimaru

Mikio Ohno

Hideaki Kosha

Tsutomu Sugisaki

Kazuo Hasumi

Kunihiko Honda

Kenzo Hasunuma

Mashahi Aonuma

A magnetic recording medium having a ferromagnetic metal thin film on at least one surface of a non-magnetic support. The magnetic recording medium has a surface layer containing at least either one of fluorine compounds represented by the following formulae (1) and (2):

Magnetic recording medium having a carbon protective layer and a

A magnetic recording medium having a ferromagnetic metal thin film formed over at least one surface of a non-magnetic support, wherein the improvement has a lubricant layer consisting essentially of at least one of unsaturated bond-containing fluoroalkyl carboxylic acid esters which are represented by the following formulae (1) to (3):

Magnetic recording medium having a cobalt thin film magnetic layer,

A magnetic recording medium having a magnetic recording layer on at least one surface of a non-magnetic support, wherein the magnetic recording layer has thereon a lubricant layer containing at least one fluoroalkyl sulfo compound having an ether or ester linkage, which is represented by the following formula (1). The magnetic recording medium is free from corrosion of the magnetic recording layer and has a low coefficient of friction and excellent running durability and shelf stability. The lubricant layer is particularly suitable for a magnetic recording medium having a metal thin film with or without an inorganic protective film as a magnetic recording layer.

Magnetic recording medium having a lubricant layer of a fluoroalkyl

A magnetic recording medium comprising a non-magnetic support having provided thereon a magnetic layer comprising a ferromagnetic powder and a binder material, wherein the magnetic layer contains at least a vinyl chloride copolymer binder having at least one polar group selected from --SO.sub.3 M and --COOM, wherein M represents a hydrogen atom, an alkali metal, or an ammonium ion, and at least one epoxy group per molecule in an amount of 1.times.10.sup.-4 to 1.times.10.sup.-2 per gram, and a fatty acid amide having from 12 to 26 atoms and present in an amount of from 0.05 to 2 wt % based on the amount of the ferromagnetic powder, and wherein the content of the polar group in the vinyl chloride copolymer binder is from about 1.times.10.sup.-7 to 1.times.10.sup.-3 equivalent per gram, and wherein the vinyl chloride copolymer binder has a weight average molecular weight of from 20,000 to 100,000 and wherein the magnetic layer further contains a polyurethane resin having a polar group.

Magnetic recording medium having ferromagnetic powder, a binder

A magnetic recording medium comprising a non-magnetic support having thereon a multi-layer magnetic layer structure comprising ferromagnetic fine powder and a binder, wherein said multi-layer magnetic layer structure is formed by coating a first composition containing the ferromagnetic fine powder and a polyisocyanate compound on the non-magnetic support to form a first magnetic layer and coating a second composition containing ferromagnetic fine powder and an epoxy compound having at least one epoxy group or a coupling agent on said first magnetic layer to form a second magnetic layer, wherein coating of said second magnetic layer is conducted simultaneously with or after coating said first magnetic layer while said first magnetic layer is still in a wet state, by a simultaneous or successive multiple layered coating method.

Magnetic recording medium having multiple magnetic layers with specified

A magnetic recording medium comprising a non-magnetic support having thereon a magnetic layer comprising ferromagnetic particles disposed in a binder, the binder comprising a vinyl chloride copolymer and a polyurethane resin, wherein the polyurethane resin is a polyether polyurethane resin containing a polyether polyol having a ring structure.

Magnetic recording medium wherein the magnetic layer has as the binder

A magnetic recording medium comprising a non-magnetic support having on one surface thereof a magnetic layer and on the opposite surface thereof a backing layer comprising non-magnetic particles dispersed in a binder containing a copolymer of (a) at least one of a vinyl monomer containing a dialkylaminoalkyl group and a vinyl monomer containing a quaternary salt of a dialkylaminoalkyl group, and (b) a copolymerizable vinyl monomer.

Magnetic recording medium having a backcoat layer comprising

A method for preparing a magnetic recording medium is disclosed, comprising the steps of (1) surface-treating ferromagnetic particles with a glycidyl compound having a molecular weight of 1,000 or less and having an epoxy equivalent of 200 g/eq. or less, (2) dispersing the surface-treated ferromagnetic particles with a binder to prepare a magnetic coating composition, (3) coating the resulting magnetic coating composition on a nonmagnetic support, and then (4) drying the magnetic coating composition.

Magnetic recording medium containing magnetic particles surface treated

A magnetic recording medium comprising a non-magnetic support having provided thereon a magnetic layer comprising a binder and ferromagnetic particles dispersed therein, wherein the magnetic layer further contains a vinyl compound having an inner salt of an alkylaminoalkyl group and the magnetic layer has been irradiated with radiation.

Magnetic recording medium in which the magnetic layer contains a vinyl

A process for producing a magnetic recording medium which comprises a step of kneading a ferromagnetic powder with a binder in the presence of a solvent, a step of dispersing the resulting blend with the binder and/or solvent, and a step of coating the resulting magnetic coating composition on a nonmagnetic support followed by drying;

Process for producing a magnetic recording medium

A process of producing a magnetic recording medium comprising the steps of kneading ferromagnetic fine particles and a binder using an organic solvent to prepare a kneaded mixture, dispersing said kneaded mixture with the addition of an additional binder and/or an additional organic solvent to prepare a magnetic coating composition, and coating said magnetic coating composition on a non-magnetic support followed by drying,

Process of producing magnetic recording medium

A magnetic recording medium comprising a non-magnetic support having provided thereon a magnetic layer, containing ferromagnetic particles dispersed in a binder, wherein the binder comprises a copolymer comprising at least one vinyl compound having a dialkylaminoalkyl group and at least one copolymerizable vinyl monomer capable of being copolymerized with the vinyl compound.

Magnetic recording medium having a binder comprising a copolymer which

A magnetic recording medium comprising a support having provided on one surface thereof a magnetic layer comprising a binder and ferromagnetic particles dispersed therein, and on the opposite surface thereof a backing layer comprising a binder and non-magnetic particles dispersed therein, wherein at least one of the binders comprises a vinyl chloride copolymer resin having a vinyl chloride unit content of about 70 wt % or more based on the total amount of the binder, a nitrogen content of about from 0.01 to 1 wt % based on the total amount of the binder, and a polymerization degree of about from 250 to 700; and the non-magnetic particles comprises fine carbon particles having a DBP oil absorption of about 150 ml/100 g or more.

Magnetic recording medium

A method is described for preparing a magnetic recording medium comprising a non-magnetic support having provided thereon a magnetic layer containing a compound which is cross-linkable or polymerizable by radiation exposure, which comprises conducting a corona discharge treatment on a surface of a support, coating an aqueous dispersion of hydrophobic polymer on the surface of the support to form an undercoat layer, providing a magnetic layer on the undercoat layer, and exposing the magnetic layer to radiation.

Magnetic recording medium and method of preparing

A magnetic recording medium comprising a non-magnetic base and an overlying magnetic coating having ferromagnetic particles dispersed in a binder is disclosed. The magnetic coating is characterized by further containing a titanate coupling agent.

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Kanagawa, Japan

Hideomi Watanabe