Fujifilm Corporation

The University of Tokyo

Osaka University

Fujifilm Cornoration

Kenji Naoi

Masashi Shirata

Takashi Fujimoto

Yoichi Hosoya

Naoharu Kiyoto

Nori Miyagishima

Hiroyuki Suzuki

Toshiaki Hayashi

Michihiro Shibata

Yasushi Endo

Shin-ichi Ohkoshi

Katsuhisa Ohzeki

Wataru Kikuchi

Akito Yokozawa

Toshihiro Kariya

Nobuyuki Tada

Asuka Namai

Shigeru Shibayama

Satoshi Tanaka

Ryoji Nishimura

Takeshi Funakubo

Hiroko Tokoro

Marie Yoshikiyo

Kenta Imoto

Kenichi Yamamoto

Makoto Nakajima

Tomohito Asai

Hideo Ikeda

Koichi Yagishita

Kosuke Nakagawa

A hexagonal strontium ferrite powder, in which an average particle size is 10.0 to 25.0 nm, a content of one or more kinds of atom selected from the group consisting of a gallium atom, a scandium atom, an indium atom, and an antimony atom is 1.0 to 15.0 atom % with respect to 100.0 atom % of an iron atom, and a coercivity Hc is greater than 2,000 Oe and smaller than 4.000 Oe. A magnetic recording medium including: a non-magnetic support; and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support, in which the ferromagnetic powder is the hexagonal strontium ferrite powder. A magnetic recording and reproducing apparatus including this magnetic recording medium.

Hexagonal strontium ferrite powder, magnetic recording medium, and magnetic recording and reproducing apparatus

Provided is a recording device. The recording device includes: an external magnetic field application unit that is configured to apply an external magnetic field to a magnetic recording medium; a light irradiation unit that is configured to irradiate light; and a light focusing unit that is configured to focus the light from the light irradiation unit by resonating the light to generate an enhanced magnetic field in which a magnetic field of the light is enhanced, in which magnetization of the magnetic recording medium is inverted by applying the external magnetic field and the enhanced magnetic field to the magnetic recording medium.

Recording device and recording method

A core-shell particle includes: a core including an iron oxyhydroxide compound represented by Formula AFeOOH (in which Arepresents at least one metal element other than Fe, and a3 satisfies 0&#x3c;a3&#x3c;1) or at least one iron oxide compound selected from the group consisting of FeO, a compound represented by Formula AFeO(in which Arepresents at least one metal element other than Fe, and a1 satisfies 0&#x3c;a1&#x3c;2), FeO, and a compound represented by Formula AFeO(in which Arepresents at least one metal element other than Fe, and a2 satisfies 0&#x3c;a2&#x3c;2); and a shell which covers the core and includes a polycondensate of a metal alkoxide.

Core-shell particle and manufacturing method and fired product of the same, epsilon type iron oxide compound particle and manufacturing method of the same, and magnetic recording medium and manufacturing method of the same

Provided is a ferromagnetic powder for magnetic recording, in which an activation volume is 800 nmto 1,500 nm, an average plate ratio is 2.0 to 5.0, a rare earth atom content is 0.5 atom % to 5.0 atom %, and an aluminum atom content is greater than 10.0 atom % and equal to or smaller than 20.0 atom %, with respect to 100 atom % of iron atom, and the ferromagnetic powder is a plate-shaped hexagonal strontium ferrite powder having a rare earth atom surface layer portion uneven distribution and an aluminum atom surface layer portion uneven distribution, and a magnetic recording medium including this ferromagnetic powder for magnetic recording in a magnetic layer.

Ferromagnetic powder for magnetic recording and magnetic recording medium

Disclosed are a particle of a 13-iron oxyhydroxide-based compound represented by Formula (1), in which an average equivalent circle diameter of primary particles is 5 nm to 30 nm, and a coefficient of variation of equivalent circle diameters of the primary particles is 10% to 30% [In Formula (1), A represents at least one kind of metal element other than Fe, and a represents a number that satisfies a relationship of 0&#x2264;a&#x3c;1.], and applications thereof.&#x3b2;-AFeOOH &#x2003;&#x2003;(1)

Particles of &#x3b2;-iron oxyhydroxide-based compound, manufacturing method of the same, manufacturing method of particles of &#x3f5;-iron oxide-based compound, and manufacturing method of magnetic recording medium

The magnetic recording medium includes a non-magnetic support; and a magnetic layer including a ferromagnetic powder, in which the ferromagnetic powder is an &#x3b5;-iron oxide powder having an average particle size of 9.0 nm to 20.0 nm, and in the &#x3b5;-iron oxide powder, a content of particles having a particle size smaller than 8.0 nm is less than 20.0% by mass, a content of particles having a particle size smaller than 6.0 nm is less than 5.0% by mass, and a content of particles having a particle size greater than 25.0 nm is less than 20.0% by mass.

Magnetic recording medium, magnetic recording and reproducing device, and e-iron oxide powder

The invention provides a core-shell particle which can provide, by being calcinated, epsilon type iron oxide-based compound particles that have a small coefficient of variation of primary particle diameter and show excellent SNR and running durability when employed in a magnetic recording medium as well as applications thereof. The core-shell particle includes: a core including at least one iron oxide selected from FeOor FeO, or iron oxyhydroxide; and a shell that coats the core, the shell including a polycondensate of a metal alkoxide and a metal element other than iron, as well as applications thereof.

Core-shell particle, fired product of core-shell particle, manufacturing method of core-shell particle, epsilon type iron oxide-based compound particle, manufacturing method of epsilon type iron oxide-based compound particle, magnetic recording medium, and manufacturing method of magnetic recording medium

The &#x3b5;-iron oxide powder has an average particle size in a range of 5.0 to 16.0 nm and an uneven distribution of an M atom in a surface layer portion, in which the M atom is one or more kinds of atoms selected from the group consisting of an aluminum atom and an yttrium atom, and a content of the M atom with respect to 100 atom % of iron atoms is in a range of 4.0 to 9.5 atom %.

E-iron oxide powder, composition including the same, magnetic recording medium, and magnetic recording and reproducing device

The magnetic recording medium includes a non-magnetic support; and a magnetic layer including a ferromagnetic powder, in which the ferromagnetic powder is an &#x3b5;-iron oxide powder having an average particle size of 5.0 nm to 16.0 nm, a coercivity Hc in a vertical direction is 1,884 Oe to 3,141 Oe, a ten-point average roughness Rz of a surface of the magnetic layer is 35.0 nm to 45.0 nm, and a ratio Rp/Rz of a maximum peak height Rp of the surface of the magnetic layer to the Rz is 0.25 to 1.00.

Magnetic recording medium and magnetic recording and reproducing device

Provided is hexagonal strontium ferrite powder for magnetic recording, in which an activation volume is 800 to 1,500 nm, a content of rare earth atom with respect to 100 atom % of iron atom is 0.5 to 5.0 atom %, and a rare earth atom surface portion uneven distribution is provided.

Hexagonal strontium ferrite powder for magnetic recording and magnetic recording medium

A hexagonal strontium ferrite powder, in which an average particle size is 10.0 to 25.0 nm, a content of one or more kinds of atom selected from the group consisting of a gallium atom, a scandium atom, an indium atom, and an antimony atom is 1.0 to 15.0 atom % with respect to 100.0 atom % of an iron atom, and a coercivity Hc is greater than 2,000 Oe and smaller than 4,000 Oe. A magnetic recording medium including: a non-magnetic support; and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support, in which the ferromagnetic powder is the hexagonal strontium ferrite powder. A magnetic recording and reproducing apparatus including this magnetic recording medium.

A magnetic recording medium for microwave-assisted recording, including a non-magnetic support; and a magnetic layer containing a ferromagnetic powder and a binding agent, in which the ferromagnetic powder has an average particle size of 5 nm to 20 nm, and a coefficient of variation of a particle size distribution of 35% or lower, and the magnetic layer has a thickness of 25.0 nm to 100.0 nm, and a thickness variation of 1.0 nm to 12.0 nm. A magnetic recording device including a magnetic recording medium and a magnetic head for microwave-assisted recording. A manufacturing method of a magnetic recording medium having a servo pattern on a magnetic layer.

Magnetic recording medium for microwave-assisted recording, magnetic recording device, and manufacturing method of magnetic recording medium

A magnetic recording medium, a composition for it, and a magnetic recording and reproducing apparatus are provided. The medium includes a non-magnetic support; and a magnetic layer including a ferromagnetic powder and a binding agent on the support. The magnetic layer also includes a compound including one or more partial structures selected from partial structures represented by Formulas 1 and 2, and a polyalkyleneimine chain. The composition for the recording medium includes a ferromagnetic powder and the compound. In Formulas 1 and 2, Land Leach independently represents a divalent linking group, Zand Zeach independently represents a monovalent group represented by &#x2014;OM or a monovalent group represented by &#x2014;OA, M represents a hydrogen atom or an alkali metal atom, and Arepresents an ammonium cation. 

Magnetic recording medium including specified compound, magnetic recording and reproducing apparatus, and composition for magnetic recording medium

The magnetic recording medium includes: a non-magnetic support; and a magnetic layer including ferromagnetic powder and a binding agent, wherein the ferromagnetic powder is selected from the group consisting of hexagonal strontium ferrite powder and &#x3b5;-iron oxide powder, and has an average particle size of 5 nm or more and 20 nm or less, wherein the magnetic layer has a servo pattern, and wherein an average area Sdc of magnetic clusters of the magnetic recording medium in a DC demagnetization state, measured by a magnetic force microscope is 0.2&#xd7;10nmor more and less than 5.0&#xd7;10nm.

Magnetic recording medium and magnetic recording and reproducing apparatus

An object of the present invention is to provide a pressure-sensitive adhesive sheet for a touch panel which is excellent for the operability of a capacitance-type touch panel, which is able to suppress the occurrence of malfunctions in a capacitance-type touch panel in a wide range of temperature environments from low temperatures to high temperatures, and which is also excellent in pressure-sensitive adhesion. In addition, another object of the present invention is to provide a laminate for a touch panel and a capacitance-type touch panel which include a pressure-sensitive adhesive sheet for a touch panel. In the pressure-sensitive adhesive sheet for a touch panel of the present invention, a relative dielectric constant obtained by impedance measurement at 1 MHz at 20&#xb0; C. is 4.0 or more, a temperature dependency obtained from a temperature dependency evaluation test is 25% or less, and a 180 degree peel strength with respect to glass is 0.2 to 1.2 N/mm.

Growing community of inventors

Minami-ashigara, Japan

Kenji Naoi