FujiFilm Assigned Nine Patents

Magnetic tape device, magnetic reproducing method, and head tracking servo
FujiFilm Corporation, Tokyo, Japan, has been assigned a patent (10,490,220) developed by Kasada, Norihito, and Ozawa, Eiki, Minami-ashigara, Japan, for “magnetic tape device, magnetic reproducing method, and head tracking servo method.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”Provided is a magnetic tape device in which a magnetic tape transportation speed is equal to or lower than 18 m/sec, Ra measured regarding a surface of a magnetic layer of a magnetic tape is equal to or smaller than 2.0 nm, a C–H derived C concentration calculated from a C–H peak area ratio of C1s spectra obtained by X-ray photoelectron spectroscopic analysis performed on the surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is 45 to 65 atom %, and .DELTA.SFD, =SFD.sub.25.degree.C.-SFD.sub.-190.degree. C.) in a longitudinal direction of the magnetic tape is equal to or smaller than 0.50, with the SFD.sub.25.degree. C. being SFD measured in a longitudinal direction of the magnetic tape at a temperature of 25.degree. C., and the SFD.sub.-190.degree. C. being SFD measured at a temperature of -190.degree. C.”

The patent application was filed on October 15, 2018 (16/160,377).

Magnetic tape device and magnetic reproducing method employing TMR head
FujiFilm Corporation, Tokyo, Japan, has been assigned a patent (10,482,915) developed by Ozawa, Eiki, Kaneko, Tetsuya, and Kasada, Norihito, Minami-ashigara, Japan, for “magnetic tape device and magnetic reproducing method employing TMR head and magnetic tape having characterized magnetic layer.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”The magnetic tape device includes: a magnetic tape, and a reproducing head, in which the reproducing head is a TMR head, the magnetic tape includes a non-magnetic support, and a magnetic layer including ferromagnetic powder, a binding agent, and fatty acid ester on the non-magnetic support, a full width at half maximum of spacing distribution measured by optical interferometry regarding a surface of the magnetic layer before performing a 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 by optical interferometry regarding the surface of the magnetic layer after performing the vacuum heating with respect to the magnetic tape and a spacing measured before performing the vacuum heating is greater than 0 nm and equal to or smaller than 9.0 nm.”

The patent application was filed on December 26, 2017 (15/854,439).

Magnetic tape having characterized magnetic layer
FujiFilm Corporation, Tokyo, Japan, has been assigned a patent (10,482,913) developed by Kasada, Norihito, Minami-ashigara, Japan, for a “magnetic tape having characterized magnetic layer.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”A magnetic tape includes a non-magnetic support, a non-magnetic layer including non-magnetic powder and a binding agent on the non-magnetic support, and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic layer. The total thickness of the non-magnetic layer and the magnetic layer is less than or equal to 0.60 .mu.m. The magnetic layer includes an abrasive, and the percentage of a plan view maximum area of the abrasive confirmed in a region having a size of 4.3 .mu.m.times.6.3 .mu.m of the surface of the magnetic layer with respect to the total area of the region, obtained by plane observation performed by using a scanning electron microscope, is greater than or equal to 0.02% and less than 0.06%. Also, the logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the magnetic layer is less than or equal to 0.050.”

The patent application was filed on February 20, 2018 (15/900,345).

Magnetic tape having characterized magnetic layer and hexagonal ferrite powder
FujiFilm Corporation, Tokyo, Japan, has been assigned a patent (10,477,072) developed by Kasada, Norihito, Minami-ashigara, Japan, for a “magnetic tape having characterized magnetic layer and hexagonal ferrite powder.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”A magnetic tape is provided in which ferromagnetic powder included in a magnetic layer is ferromagnetic hexagonal ferrite powder having an activation volume less than or equal to 1,600 nm.sup.3. The magnetic layer includes one or more components selected from a fatty acid and a fatty acid amide, and an abrasive. The C–H derived C concentration calculated from the C–H peak area ratio of C1s spectra obtained by X-ray photoelectron spectroscopic analysis performed on the surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is greater than or equal to 45 atom %. Also, the tilt cos .theta. of the ferromagnetic hexagonal ferrite powder with respect to the surface of the magnetic layer acquired by cross section observation performed by using a scanning transmission electron microscope is 0.85 to 1.00.”

The patent application was filed on June 13, 2017 (15/620,916).

Magnetic tape having characterized backcoat layer and method of manufacturing
FujiFilm Corporation, Tokyo, Japan, has been assigned a patent (10,475,481) developed by Oyanagi, Masahito, Kasada, Norihito, and Ozawa, Eiki, Minami-ashigara, Japan, for “magnetic tape having characterized backcoat layer and method of manufacturing the same.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”The magnetic tape has a magnetic layer and a backcoat layer. The Ra on the magnetic layer side surface is less than or equal to 1.8 nm, the coefficient of friction measured on the base portion of the magnetic layer side surface is less than or equal to 0.35, and the Ra measured on the backcoat layer side surface is less than or equal to 5.0 nm. The backcoat layer contains a fatty acid ester. In addition, the FWHM.sub.before measured on the backcoat layer side surface before vacuum heating is greater than 0 nm but less than or equal to 10.0 nm, the FWHM.sub.after after vacuum heating is greater than 0 nm but less than or equal to 10.0 nm, and the difference between the spacing measured on the backcoat layer side surface after and before vacuum heating is greater than 0 nm but less than or equal to 8.0 nm.”

The patent application was filed on February 2, 2017 (15/422,821).

Magnetic tape having characterized back coating and magnetic layers
FujiFilm Corporation, Tokyo, Japan, has been assigned a patent (10,475,480) developed by Kurokawa, Takuto, and Kasada, Norihito, Minami-ashigara, Japan, for a “magnetic tape having characterized back coating and magnetic layers.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”A magnetic tape includes a non-magnetic support, a magnetic layer including ferromagnetic powder and a binding agent on one surface side of the non-magnetic support, and a back coating layer including non-magnetic powder and a binding agent on the other surface side of the non-magnetic support. The center line average surface roughness Ra measured regarding a surface of the magnetic layer is less than or equal to 1.8 nm. The contact angle with respect to 1-bromonaphthalene measured regarding the surface of the magnetic layer is 45.0.degree. to 55.0.degree.. Also, the logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the back coating layer is less than or equal to 0.060.”

The patent application was filed on February 20, 2018 (15/900,242).

Magnetic tape device and head tracking servo method employing TMR element servo head and magnetic tape with characterized magnetic layer
FujiFilm Corporation, Tokyo, Japan, has been assigned a patent (10,460,756) developed by Kasada, Norihito, and Ozawa, Eiki, Minami-ashigara, Japan, for “magnetic tape device and head tracking servo method employing TMR element servo head and magnetic tape with characterized magnetic layer.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”A magnetic tape device includes: a magnetic tape including a servo pattern on a magnetic layer, and a Tunneling Magnetoresistive, (TMR) head as a servo head, in which the center line average surface roughness Ra measured regarding a surface of the magnetic layer of the magnetic tape is equal to or smaller than 2.0 nm, the logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the magnetic layer is equal to or smaller than 0.050, and .DELTA.SFD in a longitudinal direction of the magnetic tape calculated by Expression 1: .DELTA.SFD=SFD.sub.25.degree. C.-SFD.sub.-190.degree. C. is equal to or smaller than 0.50, wherein the SFD.sub.25.degree. C. is SFD measured in a longitudinal direction of the magnetic tape at a temperature of 25.degree. C., and the SFD.sub.-190.degree. C. is SFD measured in a longitudinal direction of the magnetic tape at a temperature of -190.degree. C.”

The patent application was filed on February 20, 2018 (15/900,080).

Magnetic tape having characterized magnetic layer
FujiFilm Corporation, Tokyo, Japan, has been assigned a patent (10,453,488) developed by Kurokawa, Takuto, and Kasada, Norihito, Minami-ashigara, Japan, for a “magnetic tape having characterized magnetic layer.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”A magnetic tape includes a non-magnetic support, and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support. The center line average surface roughness Ra measured regarding the surface of the magnetic layer is less than or equal to 1.8 nm. The logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the magnetic layer is less than or equal to 0.050, and the contact angle with respect to 1-bromonaphthalene measured regarding the surface of the magnetic layer is 45.0.degree. to 55.0.degree.”

The patent application was filed on February 20, 2018 (15/900,379).

Magnetic tape device with magnetic tape having particular C-H derived C concentration
FujiFilm Corporation, Tokyo, Japan, has been assigned a patent (10,438,628) developed by Kasada, Norihito, Ozawa, Eiki, and Kaneko, Tetsuya, Minami-ashigara, Japan, for “magnetic tape device with magnetic tape having particular C-H derived C concentration and magnetic reproducing method.“

The abstract of the patent published by the U.S. Patent and Trademark Office states: ”The magnetic tape device includes: a magnetic tape, and a reproducing head, in which a magnetic tape transportation speed of the magnetic tape device is equal to or lower than 18 m/sec, the reproducing head is a magnetic head including a tunnel magnetoresistance effect type element as a reproducing element, the magnetic tape includes a non-magnetic support, and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, the magnetic layer includes one or more components selected from the group consisting of fatty acid and fatty acid amide, and a C–H derived C concentration calculated from a C–H peak area ratio of C1s spectra obtained by X-ray photoelectron spectroscopic analysis performed on the surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is 45 to 65 atom %.”

The patent application was filed on December 26, 2017 (15/854,383).