Identified Magnetic Toner Patents (Class 430/122.5)
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Patent number: 11720036Abstract: A toner comprising a toner particle comprising a binder resin including a polyester resin, and a polyolefin resin having a sulfonic acid group, wherein the polyolefin resin having a sulfonic acid group is a polymer in which a vinyl polymer is bonded to a polyolefin, a content ratio of a monomer unit containing a sulfonic acid group in the vinyl polymer is from 1.0 mass % to 20.0 mass %, in a FT-IR spectrum obtained through measurement of a large particle size toner and a small particle size toner resulting from dividing, on a number basis, the toner into two substantially equal parts, a ratio of an intensity of a maximum absorption peak in a range from 1130 cm?1 to 1170 cm?1 with respect to an intensity of a maximum absorption peak in a range from 1713 cm?1 to 1723 cm?1 exhibits a specific relationship.Type: GrantFiled: June 10, 2021Date of Patent: August 8, 2023Assignee: CANON KABUSHIKI KAISHAInventors: Takakuni Kobori, Kenta Mitsuiki, Hitoshi Sano, Wakiko Katsumata, Daisuke Yamashita, Yosuke Iwasaki, Takeshi Ohtsu, Takaho Shibata, Masaharu Miura, Koh Ishigami, Yuichi Mizo
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Patent number: 9250551Abstract: An electrostatic latent image developing toner is manufactured by mixing an aqueous medium dispersion liquid (X) containing negatively chargeable toner cores and an aqueous medium dispersion liquid (Y) containing positively chargeable resin particulates, followed by stirring the mixture liquid to form shell layers each on a surface of the toner cores with the resin particulates. The shell layers are formed with the resin particulates subjected to a stirring treatment together with an anionic surfactant.Type: GrantFiled: March 28, 2014Date of Patent: February 2, 2016Assignee: KYOCERA Document Solutions Inc.Inventors: Seishi Ojima, Ryotaro Komada
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Patent number: 9116460Abstract: An image forming apparatus includes a latent image forming device that forms a latent image, a latent image carrier that carries the latent image, a development device that develops the latent image, and a controller. The development device includes a developer carrier that faces the latent image carrier and carries toner on a rotary surface thereof that rotates in a rotation direction perpendicular to a width direction of the developer carrier, and a regulation member that regulates the thickness of a layer of the toner on the surface of the developer carrier. The controller moves the toner on lateral end regions in the width direction of the surface of the developer carrier toward the latent image carrier. The end regions are located outside a maximum image forming region within a regulation member facing region of the surface of the developer carrier facing the regulation member.Type: GrantFiled: November 27, 2013Date of Patent: August 25, 2015Assignee: Ricoh Company, Ltd.Inventors: Yasuhide Matsuno, Naoki Nakatake, Yuji Nagatomo, Takahiro Sanada
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Patent number: 8507170Abstract: An image-forming method includes forming an electrostatic image on an electrostatic image bearing member which has been charged; developing the electrostatic image to form a toner image; transferring the toner image on the electrostatic image bearing member with or without mediating an intermediate transferring member onto a transfer material; and fixing the toner image on the transfer material. The electrostatic image bearing member is a photosensitive member obtained by sequentially laminating a photoconductive layer and a surface layer formed of hydrogenated amorphous silicon carbide, and a sum of an atomic density of silicon atoms and an atomic density of carbon atoms in the surface layer of the photosensitive member is 6.60×1022 atoms/cm3 or more. The toner has a binder resin and magnetic iron oxide particles, and the magnetic iron oxide particles contain Fe(2+) at a content of 20.0 mass % or more and 25.0 mass % or less.Type: GrantFiled: July 24, 2009Date of Patent: August 13, 2013Assignee: Canon Kabushiki KaishaInventors: Tooru Takahashi, Katsuhisa Yamazaki, Syuhei Moribe, Daisuke Yoshiba, Masami Fujimoto
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Patent number: 8247150Abstract: A carrier for developing an electrostatic latent image which includes a core material and a resin coating layer provided on the core material. The resin coating layer includes a resin and a particulate tin oxide, and the surface of the particulate tin oxide is coated with carbon.Type: GrantFiled: September 17, 2009Date of Patent: August 21, 2012Assignee: Ricoh Company, Ltd.Inventors: Hitoshi Iwatsuki, Kimitoshi Yamaguchi, Minoru Masuda, Yutaka Takahashi, Koichi Sakata
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Patent number: 7862977Abstract: A method to form an image using a trickle developing system, wherein (a) the toner comprises colorant particles with a volume median diameter of 3 to 8 ?m having first inorganic particles on surfaces of the colorant particles to form toner particles; (b) the carrier comprises magnetic particles with a weight average particle diameter (D4) of 20 to 40 ?m having second inorganic particles on surfaces of the magnetic particles to form carrier particles; and (c) an area ratio of element (A) based on a total area of surfaces of the carrier particles is 0.5 to 3.0 area % determined by using an X-ray analysis, provided that element (A) represents one or more elements commonly contained in the first inorganic particles and in the second inorganic particles.Type: GrantFiled: April 3, 2007Date of Patent: January 4, 2011Assignee: Konica Minolta Business Technologies, Inc.Inventors: Makoto Kobayashi, Yoshiyasu Matsumoto
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Patent number: 7682765Abstract: To provide a toner for developing electrostatic images which is not easily cause the phenomenon of toner-spent, constituent materials are so selected that a charge control resin has hardness which is the same as the hardness of a binder resin or the charge control resin is harder than the binder resin, as measured with a scanning probe microscope in a viscoelasticity evaluation mode in respect to the binder resin and the charge control resin which are present in the particle interiors or particle surfaces of the toner.Type: GrantFiled: December 12, 2005Date of Patent: March 23, 2010Assignee: Canon Kabushiki KaishaInventors: Etsuko Sugawa, Chieko Mihara, Takashi Kenmoku, Tatsuki Fukui, Shinya Kozaki, Tsutomu Honma, Tetsuya Yano, Shigeki Yoshida
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Patent number: 7575840Abstract: The toner of the present invention is characterized in that the charges rise up rapidly, the charge quantity is not insufficient nor excessive, the photoreceptor contamination is minimized and the toner is endurable under harsh conditions and against the high stress usage. The magnetic particle contained in the toner is of average particle size 0.01 ?m through 0.50 ?m, is of octahedron shape that is a convex polyhedron surrounded by eight triangles as a basis, each of vertexes and edges of the octahedron being in a curved surface shape and having a portion that can be taken as a straight line on the outer periphery of a projected image of said octahedron. The sphericity of the toner is 0.94 through 0.98. Here, the sphericity is defined by C2/C1, where C1 is a circumferential length of an image projected on a plane and C2 is a circumferential length of an assumed circle area as same as that of the projected image. Further, a number content of the toner of particle size 0.6 ?m through 2.Type: GrantFiled: March 31, 2006Date of Patent: August 18, 2009Assignee: Kyocera Mita CorporationInventors: Kouzou Teramoto, Yukinori Nakayama, Kousuke Satou, Hiroshi Mizuhata
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Patent number: 7575839Abstract: The object is to provide a magnetic toner with which toner scattering, toner spent to carrier, development of scratch streaks by the magnetic brush on the photoreceptor drum can be prevented for a prolonged period and a good image characteristic (in image density and background fogging) can be maintained for a prolonged period, and an image forming method using the magnetic toner. A two-component developer comprising carriers and toner which contains magnetic particle at least in a binder resin thereof, the magnetic particle being of basically polyhedral shaped shape, vertexes and edges of said polyhedral shape being curved surfaces, said shape having peripheral parts taken as straight lines in a projected image thereof, saturation magnetization of said toner in a magnetic field of 79.6 kA/m being 4.0 to 15.Type: GrantFiled: March 30, 2006Date of Patent: August 18, 2009Assignee: Kyocera Mita CorporationInventors: Yukinori Nakayama, Kousuke Satou, Kouzou Teramoto, Hiroshi Mizuhata
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Patent number: 7361442Abstract: A developing method is provided in which a developer is carried on a developer carrying member, a thin layer of the developer is formed thereon and a latent image on a latent image bearing member is developed with a developer. The developer is composed of magnetic toner particles containing a binder resin and a magnetic powder. The magnetic powder has a saturation magnetization of 67.0 Am2/kg to 75.0 Am2/kg in a magnetic field of 79.6 kA/m (1,000 oersteds) and has a residual magnetization of 4.5 Am2/kg or less. In the surface profile of the conductive resin coat layer of the developer carrying member, the relationship 1.00?S/A?1.65 is satisfied where S is a surface area of regions zoned by an area A of microscopic unevenness regions from which parts exceeding a reference plane by 0.5×r (r: weight average particle diameter (?m) of a toner used) or more have been excluded.Type: GrantFiled: April 17, 2007Date of Patent: April 22, 2008Assignee: Canon Kabushiki KaishaInventors: Satoshi Otake, Masayoshi Shimamura, Yusutaka Akashi, Kazunori Saiki, Nene Dojo, Minoru Ito, Michihisa Magome, Eriko Yanase, Tatsuya Nakamura
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Publication number: 20070238043Abstract: A developing method is provided in which a developer is carried on a developer carrying member, a thin layer of the developer is formed thereon and a latent image on a latent image bearing member is developed with a developer. The developer is composed of magnetic toner particles containing a binder resin and a magnetic powder. The magnetic powder has a saturation magnetization of 67.0 Am2/kg to 75.0 Am2/kg in a magnetic field of 79.6 kA/m (1,000 oersteds) and has a residual magnetization of 4.5 Am2/kg or less. In the surface profile of the conductive resin coat layer of the developer carrying member, the relationship 1.00?S/A?1.65 is satisfied where S is a surface area of regions zoned by an area A of microscopic unevenness regions from which parts exceeding a reference plane by 0.5×r (r: weight average particle diameter (?m) of a toner used) or more have been excluded.Type: ApplicationFiled: April 17, 2007Publication date: October 11, 2007Applicant: CANON KABUSHIKI KAISHAInventors: Satoshi Otake, Masayoshi Shimamura, Yusutaka Akashi, Kazunori Saiki, Nene Dojo, Minoru Ito, Michihisa Magome, Eriko Yanase, Tatsuya Nakamura