-
公开(公告)号：US20180240478A1
公开(公告)日：2018-08-23
申请号：US15899587
申请日：2018-02-20
Applicant: FUJIFILM Corporation
Inventor： Norihito KASADA , Eiki OZAWA
Abstract: The magnetic tape device includes a TMR head as a reproducing head; and a magnetic tape which includes a non-magnetic support, and a magnetic layer including ferromagnetic hexagonal ferrite powder and a binding agent on the non-magnetic support, an XRD intensity ratio (Int(110)/Int(114)) of a hexagonal ferrite crystal structure obtained by an X-ray diffraction analysis of the magnetic layer by using an In-Plane method is 0.5 to 4.0, a vertical direction squareness ratio of the magnetic tape is 0.65 to 1.00, a center line average surface roughness Ra measured regarding a surface of the magnetic layer is equal to or smaller than 2.0 nm, and a logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the magnetic layer is equal to or smaller than 0.050.
-
公开(公告)号：US20170372740A1
公开(公告)日：2017-12-28
申请号：US15624897
申请日：2017-06-16
Applicant: FUJIFILM Corporation
Inventor： Eiki OZAWA , Tetsuya KANEKO , Norihito KASADA
Abstract: Provided is a magnetic tape in which the total thickness is equal to or smaller than 5.30 μm, the magnetic layer includes a timing-based servo pattern, a magnetic layer surface Ra is equal to or smaller than 1.8 nm, the magnetic layer includes fatty acid ester, a full width at half maximum of spacing distribution measured by optical interferometry regarding the surface of the magnetic layer before performing vacuum heating with respect to the magnetic tape is greater than 0 nm and equal to or smaller than 7.0 nm, a full width at half maximum of spacing distribution measured after performing the vacuum heating is greater than 0 nm and equal to or smaller than 7.0 nm, and a difference between a spacing measured after performing the vacuum heating and a spacing measured before performing the vacuum heating is greater than 0 nm and equal to or smaller than 8.0 nm.
-
公开(公告)号：US20170372736A1
公开(公告)日：2017-12-28
申请号：US15628814
申请日：2017-06-21
Applicant: FUJIFILM Corporation
Inventor： Tetsuya KANEKO , Norihito KASADA , Eiki OZAWA
CPC classification number: G11B5/588 , G11B5/584 , G11B5/70 , G11B5/70678 , G11B5/7085 , G11B5/78
Abstract: The magnetic tape includes a non-magnetic support; and a magnetic layer including ferromagnetic powder and a binder on the non-magnetic support, in which the total thickness of the magnetic tape is equal to or smaller than 5.30 μm, the magnetic layer includes a timing-based servo pattern, a center line average surface roughness Ra measured regarding a surface of the magnetic layer is equal to or smaller than 1.8 nm, the ferromagnetic powder is ferromagnetic hexagonal ferrite powder, the magnetic layer includes an abrasive, and a tilt cos θ of the ferromagnetic hexagonal ferrite powder with respect to a surface of the magnetic layer acquired by cross section observation performed by using a scanning transmission electron microscope is 0.85 to 1.00.
-
公开(公告)号：US20170355022A1
公开(公告)日：2017-12-14
申请号：US15615871
申请日：2017-06-07
Applicant: FUJIFILM Corporation
Inventor： Tetsuya KANEKO , Norihito KASADA , Eiki OZAWA
CPC classification number: G11B5/78 , G11B5/584 , G11B5/7023 , G11B5/70615 , G11B5/70678 , G11B5/714
Abstract: The magnetic tape includes a magnetic layer having ferromagnetic powder and a binder on a non-magnetic support, in which the magnetic layer includes a timing-based servo pattern, the ferromagnetic powder is ferromagnetic hexagonal ferrite powder having an activation volume equal to or smaller than 1,600 nm3, and an edge shape of the timing-based servo pattern specified by a magnetic force microscope observation is a shape in which a difference (l99.9−l0.1) between a value l99.9 of a cumulative frequency function of 99.9% of a position deviation width from an ideal shape in a longitudinal direction of the magnetic tape and a value l0.1 of the cumulative frequency function of 0.1% thereof is equal to or smaller than 180 nm.
-
15.发明公开公开(公告)号：US20230290375A1
公开(公告)日：2023-09-14
申请号：US18182437
申请日：2023-03-13
Applicant: FUJIFILM Corporation
Inventor： Eiki OZAWA , Takashi FUJIMOTO
CPC classification number: G11B5/70642 , G11B5/714 , G11B5/7356 , G11B5/00813
Abstract: The magnetic recording medium includes a non-magnetic support, and a magnetic layer including a ferromagnetic powder. A magnetic tape cartridge and a magnetic recording and reproducing device include the magnetic recording medium. The ferromagnetic powder is an ε-iron oxide powder, and a ferromagnetic powder filling rate of a magnetic layer cross section obtained by observing a cross section of the magnetic layer with a scanning electron microscope is 0.60 or more and 0.80 or less.
-
Patent Agency Ranking
16.发明公开公开(公告)号：US20230238025A1
公开(公告)日：2023-07-27
申请号：US18191983
申请日：2023-03-29
Applicant: FUJIFILM Corporation
Inventor： Eiki OZAWA , Takashi FUJIMOTO
CPC classification number: G11B5/70642 , G11B5/702 , G11B5/712
Abstract: Provided are: a magnetic recording medium including a non-magnetic support and a magnetic layer containing a ferromagnetic powder, in which the ferromagnetic powder is an ε-iron oxide powder, a vertical switching field distribution SFD of the magnetic recording medium is 0.20 or more and 3.00 or less at a measurement temperature of 25° C., and an inclination of SFD obtained from SFD at a measurement temperature of 10° C., SFD at a measurement temperature of 25° C., and SFD at a measurement temperature of 40° C. is 0.003° C.-1 or more and 0.080° C.-1 or less; a magnetic tape cartridge including the magnetic recording medium which is a magnetic tape; and a magnetic recording and reproducing device including the magnetic recording medium.
-
17.发明申请公开(公告)号：US20230100028A1
公开(公告)日：2023-03-30
申请号：US17955137
申请日：2022-09-28
Applicant: FUJIFILM Corporation
Inventor： Takashi FUJIMOTO , Eiki OZAWA
Abstract: A magnetic recording medium including a magnetic layer including a ferromagnetic powder. The ferromagnetic powder is an ε-iron oxide powder, and a ratio of Hr (45°) to Hr (0°)(Hr (45°)/Hr (0°)) is 0.50 or less. The Hr (0°) is a residual coercive force Hr obtained by applying a pulse magnetic field having a pulse width of 0.76 ms in an in-plane direction of the magnetic recording medium, and the Hr (45°) is a residual coercive force Hr obtained by setting an angle of the magnetic recording medium in the in-plane direction to 0°, setting an angle of the magnetic recording medium in a vertical direction to 90°, and making a pulse magnetic field having a pulse width of 0.76 ms be incident from a direction inclined by 45° toward the vertical direction from the in-plane direction and applying the pulse magnetic field to the magnetic recording medium.
-
公开(公告)号：US20210295865A1
公开(公告)日：2021-09-23
申请号：US17330680
申请日：2021-05-26
Applicant: FUJIFILM Corporation
Inventor： Norihito KASADA , Eiki OZAWA , Atsushi MUSHA
Abstract: The magnetic tape includes a non-magnetic support; and a magnetic layer, in which the magnetic layer has a timing-based servo pattern, an edge shape of the timing-based servo pattern, specified by magnetic force microscopy is a shape in which a difference L99.9−L0.1 between a value L99.9 of a cumulative distribution function of 99.9% and a value L0.1 of a cumulative distribution function of 0.1% in a position deviation width from an ideal shape of the magnetic tape in a longitudinal direction is 180 nm or less, and an absolute value ΔN of a difference between a refractive index Nxy of the magnetic layer, measured in an in-plane direction and a refractive index Nz of the magnetic layer, measured in a thickness direction is 0.25 or more and 0.40 or less.
-
19.发明申请公开(公告)号：US20210287707A1
公开(公告)日：2021-09-16
申请号：US17196296
申请日：2021-03-09
Applicant: FUJIFILM Corporation
Inventor： Norihito KASADA , Eiki OZAWA , Takashi FUJIMOTO
Abstract: The magnetic recording medium includes a non-magnetic support, and a magnetic layer containing a ferromagnetic powder in which the ferromagnetic powder is c-iron oxide powder, and a coercivity of a magnetic recording medium in a vertical direction measured after pressing the magnetic layer at a pressure of 70 atm is 3,000 Oe to 10,000 Oe.
-
公开(公告)号：US20210090599A1
公开(公告)日：2021-03-25
申请号：US17022886
申请日：2020-09-16
Applicant: FUJIFILM Corporation
Inventor： Megumi NAKANO , Eiki OZAWA , Norihito KASADA
Abstract: The magnetic recording medium includes a non-magnetic support; and a magnetic layer including a ferromagnetic powder, in which one or more kinds of component selected from the group consisting of a fatty acid and a fatty acid amide are included in a portion of the magnetic layer side on the non-magnetic support, and a C—H derived C concentration calculated from a C—H peak surface area ratio in C1s spectra obtained by X-ray photoelectron spectroscopic analysis performed on a surface of the magnetic layer at a photoelectron take-off angle of 10 degrees, after pressing the magnetic layer at a pressure of 70 atm is 45 atom % or more.
-
-
-
-
-
-
-
-
-
Search Results
101
records
(took 0.023 seconds)
