Patents by Inventor Katsuyuki KITAJIMA
Katsuyuki KITAJIMA has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20180004146Abstract: An image forming apparatus includes a fixing unit that includes a heating and pressurizing member, and fixes the toner image by performing the operation of heating and pressurizing on the toner image on a recording medium twice or more times with the heating and pressurizing member, wherein the toner contains a toner particle which contains a binder resin containing a crystalline polyester resin, a colorant, and a release agent, and an external additive, and satisfies Expression: 2?tan ?P1?2.5, wherein tan ?P1 represents a maximum value of a mechanical loss tangent existing in a range where a complex elastic modulus is from 1×106 Pa to 1×108 Pa, which is measured at an angular frequency of 6.28 rad/sec and a distortion amount of 0.3%.Type: ApplicationFiled: February 2, 2017Publication date: January 4, 2018Applicant: FUJI XEROX CO., LTD.Inventors: Naoki OTA, Masataka KURIBAYASHI, Takafumi KOIDE, Yusuke FUKUDA, Katsuyuki KITAJIMA, Yasuhisa MOROOKA
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Patent number: 9720356Abstract: An image forming apparatus includes a developing unit that stores a developer containing a toner and develops an electrostatic charge image on a image holding member by the developer to form a toner image, a transfer unit that transfers the toner image on the image holding member onto a recording medium, and a fixing unit that performs an operation of heating and pressing twice or more to the toner image on the recording medium by at least one heating and pressing member which contacts with the toner image, wherein the toner has a sea and island structure of a sea portion containing a binder resin and an island portion containing a release agent, a maximum frequent value and a skewness in distribution of eccentricity B of the island portion is 0.75 to 0.95 and ?1.10 to ?0.50, respectively, and eccentricity B is defined in the specification.Type: GrantFiled: November 13, 2015Date of Patent: August 1, 2017Assignee: FUJI XEROX CO., LTD.Inventors: Naoki Ota, Katsuyuki Kitajima, Nagahito Ichijo
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Patent number: 9547256Abstract: A developing device includes a storing unit that stores an electrostatic charge image developing toner, and a developer holding member that is provided to have a gap with an image holding member and holds the toner on a surface, wherein the developing device develops an electrostatic charge image formed on a surface of the image holding member by the toner on the developer holding member through a non-contact development to form a toner image, and wherein the toner has a sea and island structure of a sea portion containing a binder resin and an island portion containing a release agent, a maximum frequent value in distribution of the eccentricity B of the island portion is from 0.75 to 0.95, and a skewness in the distribution of the eccentricity B is from ?1.10 to ?0.50, and the eccentricity B is defined in the specification.Type: GrantFiled: November 6, 2015Date of Patent: January 17, 2017Assignee: FUJI XEROX CO., LTD.Inventors: Naoki Ota, Katsuyuki Kitajima, Nagahito Ichijo
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Patent number: 9529291Abstract: An image forming apparatus includes an electrophotographic photoreceptor, a charging unit; an electrostatic latent image forming unit, a developing unit that stores a developer containing a toner, a transfer unit, a cleaning unit and a fixation unit, wherein the toner has a sea and island structure of a sea portion containing the binder resin and an island portion containing the release agent, a maximum frequent value of the eccentricity B of the island portion containing the release agent is in a range of from 0.75 to 0.95, and a skewness of the eccentricity B is in a range of from ?1.10 to ?0.50.Type: GrantFiled: October 26, 2015Date of Patent: December 27, 2016Assignee: FUJI XEROX CO., LTD.Inventors: Naoki Ota, Katsuyuki Kitajima
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Publication number: 20160349674Abstract: An image forming apparatus includes a developing unit that stores a developer containing a toner and develops an electrostatic charge image on a image holding member by the developer to form a toner image, a transfer unit that transfers the toner image on the image holding member onto a recording medium, and a fixing unit that performs an operation of heating and pressing twice or more to the toner image on the recording medium by at least one heating and pressing member which contacts with the toner image, wherein the toner has a sea and island structure of a sea portion containing a binder resin and an island portion containing a release agent, a maximum frequent value and a skewness in distribution of eccentricity B of the island portion is 0.75 to 0.95 and ?1.10 to ?0.50, respectively, and eccentricity B is defined in the specification.Type: ApplicationFiled: November 13, 2015Publication date: December 1, 2016Applicant: FUJI XEROX CO., LTD.Inventors: Naoki OTA, Katsuyuki KITAJIMA, Nagahito ICHIJO
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Publication number: 20160349666Abstract: A developing device includes a storing unit that stores an electrostatic charge image developing toner, and a developer holding member that is provided to have a gap with an image holding member and holds the toner on a surface, wherein the developing device develops an electrostatic charge image formed on a surface of the image holding member by the toner on the developer holding member through a non-contact development to form a toner image, and wherein the toner has a sea and island structure of a sea portion containing a binder resin and an island portion containing a release agent, a maximum frequent value in distribution of the eccentricity B of the island portion is from 0.75 to 0.95, and a skewness in the distribution of the eccentricity B is from ?1.10 to ?0.50, and the eccentricity B is defined in the specification.Type: ApplicationFiled: November 6, 2015Publication date: December 1, 2016Applicant: FUJI XEROX CO., LTD.Inventors: Naoki OTA, Katsuyuki KITAJIMA, Nagahito ICHIJO
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Publication number: 20160349639Abstract: An image forming apparatus includes an electrophotographic photoreceptor, a charging unit; an electrostatic latent image forming unit, a developing unit that stores a developer containing a toner, a transfer unit, a cleaning unit and a fixation unit, wherein the toner has a sea and island structure of a sea portion containing the binder resin and an island portion containing the release agent, a maximum frequent value of the eccentricity B of the island portion containing the release agent is in a range of from 0.75 to 0.95, and a skewness of the eccentricity B is in a range of from ?1.10 to ?0.50.Type: ApplicationFiled: October 26, 2015Publication date: December 1, 2016Applicant: FUJI XEROX CO., LTD.Inventors: Naoki OTA, Katsuyuki KITAJIMA
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Patent number: 9389581Abstract: A toner for developing an electrostatic image, including: toner particles containing at least a binder resin, a release agent, and a colorant; and an external additive having a volume average particle diameter (d) of from 70 nm to 400 nm, a ratio (d/?) of the volume average particle diameter (d) to a standard deviation (?) of a volumetric basis particle diameter of from 2.0 to 12, and an average circularity of from 0.5 to 0.9.Type: GrantFiled: May 20, 2011Date of Patent: July 12, 2016Assignee: FUJI XEROX CO., LTD.Inventors: Katsuyuki Kitajima, Yutaka Saito, Michio Take, Yoshifumi Iida, Motoko Sakai
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Patent number: 9367001Abstract: An image forming apparatus includes a fixing unit that fixes a toner image on a surface of a recording medium while transporting the recording medium with a contact portion of a first member and a second member, and a moving unit that moves at least one of the first member and the second member toward a direction intersecting with a transport direction of the recording medium, wherein a toner has a sea and island structure of a sea portion containing a binder resin and an island portion containing a release agent, a maximum frequent value in distribution of the eccentricity B of the island portion containing the release agent is in a range of from 0.75 to 0.95, a skewness in the distribution of the eccentricity B is from ?1.10 to ?0.50, and the eccentricity B is defined in the specification.Type: GrantFiled: November 6, 2015Date of Patent: June 14, 2016Assignee: FUJI XEROX CO., LTD.Inventors: Katsuyuki Kitajima, Naoki Ota, Nagahito Ichijo
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Patent number: 9354558Abstract: An image forming apparatus includes a developing unit that develops an electrostatic charge image formed on an image holding member with a developer containing a toner, an intermediate transfer member, and a guide unit that guides at least one of the image holding member and the intermediate transfer member to a primary transfer position to cause a portion of the surface of the image holding member and a portion of the surface of the intermediate transfer member to follow each other, wherein the toner has a sea and island structure of a sea portion containing a binder resin and an island portion containing a release agent, and has a maximum frequent value in distribution of eccentricity B of the island portion containing the release agent and a skewness in the distribution of eccentricity B each falling within the specific ranges as described in the specification.Type: GrantFiled: November 23, 2015Date of Patent: May 31, 2016Assignee: FUJI XEROX CO., LTD.Inventors: Naoki Ota, Katsuyuki Kitajima
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Patent number: 9244392Abstract: An image forming apparatus includes a latent image forming unit that forms a latent image on a photoreceptor, a developing unit that accommodates a developer containing flake shape toner particles and develops the latent image using the developer to form a toner image on a surface of the photoreceptor, a transfer unit, a bias applying unit, and a fixing unit, wherein the flake shape toner particles have an average major axis length of from 7 ?m to 20 ?m and an average thickness of from 1 ?m to 3 ?m and contain a flake shape metallic pigment.Type: GrantFiled: July 16, 2014Date of Patent: January 26, 2016Assignee: FUJI XEROX CO., LTD.Inventors: Masataka Kuribayashi, Takafumi Koide, Katsuyuki Kitajima, Makoto Kamisaki, Yasuhisa Morooka
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Publication number: 20150248081Abstract: An image forming apparatus includes a latent image forming unit that forms a latent image on a photoreceptor, a developing unit that accommodates a developer containing flake shape toner particles and develops the latent image using the developer to form a toner image on a surface of the photoreceptor, a transfer unit, a bias applying unit, and a fixing unit, wherein the flake shape toner particles have an average major axis length of from 7 ?m to 20 ?m and an average thickness of from 1 ?m to 3 ?m and contain a flake shape metallic pigment.Type: ApplicationFiled: July 16, 2014Publication date: September 3, 2015Inventors: Masataka KURIBAYASHI, Takafumi KOIDE, Katsuyuki KITAJIMA, Makoto KAMISAKI, Yasuhisa MOROOKA
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Patent number: 9058001Abstract: An image forming apparatus includes a toner image forming unit that forms and continuously transfers a toner image based on image data onto a transported sheet from the front to the rear in a sheet transport direction as the sheet is transported, a fixing unit positioned downstream of the toner image forming unit in the transport direction and that fixes the transferred toner image onto the sheet, an image determining unit that determines whether the formed toner image is a scattering toner image that causes toner scattering during the transfer, and a speed controlling unit that controls, when it is determined that the toner image is a scattering toner image, a transport speed of the sheet and a transfer speed of the toner image to the sheet such that the speeds are slower than those when it is determined that the toner image is not a scattering toner image.Type: GrantFiled: July 5, 2013Date of Patent: June 16, 2015Assignee: FUJI XEROX CO., LTD.Inventors: Narumasa Sato, Eiji Nakai, Katsuyuki Kitajima, Makoto Kamisaki, Toyofumi Inoue, Takafumi Koide, Masataka Kuribayashi, Yoshinari Ueno, Yoshifumi Eri
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Patent number: 9052622Abstract: An electrostatic image developing toner including: a toner particle containing a coloring agent and a binder resin; and an external additive on the toner particle, wherein the external additive contains a silica particle, a primary particle of the silica particle has an average particle diameter of from 70 nm to 400 nm, a particle size distribution index of the primary particle of from 1.0 to 1.9, and an average circularity of from 0.5 to 0.9.Type: GrantFiled: August 22, 2011Date of Patent: June 9, 2015Assignee: FUJI XEROX CO., LTD.Inventors: Yutaka Saito, Katsuyuki Kitajima, Masahiro Takagi
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Patent number: 8828638Abstract: A two-component developer including a yellow toner and a carrier, the yellow toner including at least one of C. I. Pigment Yellow 155 or C. I. Pigment Yellow 185, and an azo pigment, the carrier including a first resin, magnetic particles dispersed in the first resin, and elements of Cu, Zn, Ni and Mn each in an amount of from 0 to about 2,000 ppm.Type: GrantFiled: September 28, 2009Date of Patent: September 9, 2014Assignee: Fuji Xerox Co., Ltd.Inventors: Norihito Fukushima, Manabu Serizawa, Katsuyuki Kitajima
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Patent number: 8735036Abstract: An electrostatic charge image developing toner includes: toner particles; and an external additive having an average particle diameter of from about 70 nm to about 420 nm, an average circularity of equal to or less than about 0.9, and a standard deviation of the circularity of greater than 0.2.Type: GrantFiled: March 28, 2012Date of Patent: May 27, 2014Assignee: Fuji Xerox Co., Ltd.Inventors: Katsuyuki Kitajima, Yutaka Saito, Sakon Takahashi, Michio Take
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Publication number: 20140112677Abstract: An image forming apparatus includes a toner image forming unit that forms and continuously transfers a toner image based on image data onto a transported sheet from the front to the rear in a sheet transport direction as the sheet is transported, a fixing unit positioned downstream of the toner image forming unit in the transport direction and that fixes the transferred toner image onto the sheet, an image determining unit that determines whether the formed toner image is a scattering toner image that causes toner scattering during the transfer, and a speed controlling unit that controls, when it is determined that the toner image is a scattering toner image, a transport speed of the sheet and a transfer speed of the toner image to the sheet such that the speeds are slower than those when it is determined that the toner image is not a scattering toner image.Type: ApplicationFiled: July 5, 2013Publication date: April 24, 2014Inventors: Narumasa SATO, Eiji Nakai, Katsuyuki Kitajima, Makoto Kamisaki, Toyofumi Inoue, Takafumi Koide, Masataka Kuribayashi, Yoshinari Ueno, Yoshifumi Eri
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Patent number: 8685608Abstract: A two-component developer includes: a toner; a carrier having a surface energy of from about 23 dyne/cm to about 37 dyne/cm; and an external additive having a shape factor SF1 of from about 130 to about 150 and a number-average particle diameter of from about 80 nm to about 1 ?m; and an existence ratio A of the external additive on a surface of the toner and an existence ratio B of the external additive on a surface of the carrier satisfying the relationship of the following Expression 1: 0.04?B/A?0.4.Type: GrantFiled: September 3, 2010Date of Patent: April 1, 2014Assignee: Fuji Xerox Co., Ltd.Inventors: Sakon Takahashi, Motoko Sakai, Yutaka Saito, Katsuyuki Kitajima
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Patent number: 8507167Abstract: The invention provides a toner for developing an electrostatic image including toner particles having a shape factor SF1 of 110 or more and including a binder resin, and particles of an external additive that adhere to the toner particles, wherein the particles of the external additive including first particles, and second particles which are adhered to the first particles and have a primary particle size of 0.2 times to 0.5 times as large as that of the first particles, and in an image obtained by observing the particles of the external additive with a microscope, when the projection surface area of the first particle is defined as S1 and the total of the projection surface areas of the second particles which are not hidden by the first particle is defined as S2, S2 being from 0.1 times to 0.5 times as large as S1.Type: GrantFiled: August 9, 2010Date of Patent: August 13, 2013Assignee: Fuji Xerox Co., Ltd.Inventors: Yutaka Saito, Michio Take, Yoshifumi Iida, Sakon Takahashi, Motoko Sakai, Katsuyuki Kitajima
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Publication number: 20130108949Abstract: An electrostatic charge image developing toner includes: toner particles; and an external additive having an average particle diameter of from about 70 nm to about 420 nm, an average circularity of equal to or less than about 0.9, and a standard deviation of the circularity of greater than 0.2.Type: ApplicationFiled: March 28, 2012Publication date: May 2, 2013Applicant: FUJI XEROX CO., LTD.Inventors: Katsuyuki KITAJIMA, Yutaka SAITO, Sakon TAKAHASHI, Michio TAKE