Contact Patents (Class 399/174)
  • Publication number: 20120321347
    Abstract: Two thick film charging devices or a common thick film charge device with two separated obverse conductors, sharing a common power supply are used for photoreceptor charge and erase. The thick film charging devices use a set of AC biased electrodes supported on a dielectric material which also support a counter electrode on an opposite side of the dielectric. A DC offset applied to the counter electrodes is used to set photoreceptor charge level. One DC voltage is used for photoreceptor charge and a zero or near zero DC voltage is used to erase residual charge for the photoreceptor.
    Type: Application
    Filed: June 15, 2011
    Publication date: December 20, 2012
    Applicant: XEROX CORPORATION
    Inventors: Gerald F. Daloia, Michael A. Doody
  • Patent number: 8275277
    Abstract: An image forming apparatus includes an image bearing member; a charging device, including a rotatable magnetic particle carrying member and electroconductive magnetic particles carried on the rotatable magnetic particle carrying member, for charging the image bearing member by contacting the magnetic particles to the image bearing member; a measuring device for measuring magnitudes of a first force in a first direction and a second force in a second direction which are produced in a contact region between the image bearing member and the magnetic particles, wherein the first direction and second direction are independent from each other; and a control device for controlling an image forming operation on the basis of the forces measured by the measuring device.
    Type: Grant
    Filed: June 16, 2010
    Date of Patent: September 25, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shingo Horita, Koichi Hashimoto, Ryo Nakamura, Ryota Matsumoto, Yukwi Hong
  • Publication number: 20120213552
    Abstract: An image-forming apparatus includes an image carrier that has an electrically chargeable film formed on a surface thereof and that carries an image and a charging section that charges a surface of the film on the image carrier. The charging section includes a first charging member that applies a direct-current voltage between the first charging member and the image carrier and a second charging member that applies a direct-current voltage between the second charging member and the image carrier to charge the film on the image carrier to a predetermined surface potential after the first charging member charges the film on the image carrier. The voltage applied by the first charging member is decreased such that the surface potential of the image carrier after the voltage is applied by the first charging member is decreased as the film on the image carrier becomes thinner.
    Type: Application
    Filed: August 30, 2011
    Publication date: August 23, 2012
    Applicant: FUJI XEROX CO., LTD.
    Inventor: Jin IWASAKI
  • Publication number: 20120177402
    Abstract: A charging member, a process cartridge and an electrophotographic apparatus are provided which have been so made as for any C-set images to be kept from occurring; the C-set images occurring in a charging member of an electrophotographic apparatus where the charging member and an electrophotographic photosensitive member have been left to stand in contact with each other over a long period of time. In a charging member having a conductive support and a surface layer, the surface layer is incorporated with a specific compound.
    Type: Application
    Filed: March 9, 2012
    Publication date: July 12, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tomohito Taniguchi, Satoshi Koide
  • Publication number: 20120148307
    Abstract: A blade-like charging member for charging a surface of an image bearing member by contacting thereto and by being supplied with a voltage. The charging member includes a charging portion for effecting electric discharge to the surface of the image bearing member, and a non-charging portion not effecting the electric discharge to the surface of the image bearing member. The non-charging portion is capable of contacting the image bearing member while maintaining an electrically dischargeable gap between the charging portion and the image bearing member. At least a part of the non-charging portion is made of a material having a higher resistance than that of the charging portion so as to prevent electric discharge between the non-charging portion and the surface of the image bearing member.
    Type: Application
    Filed: December 7, 2011
    Publication date: June 14, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Takayuki Namiki
  • Publication number: 20120148309
    Abstract: A charging blade for charging a surface of an image bearing drum by contacting thereto includes a charging portion for effecting electric discharge to the surface of the drum; a non-charging portion not effecting the electric discharge to the surface of the drum, wherein the non-charging portion can contact the drum to provide a dischargeable gap between the charge portion and the drum, and at least a part the non-charging portion is made of a substance having a resistance higher than that of the charge portion to prevent no discharge occurs from the non-charging portion to the surface of the drum; and a support for the non-charging portion and the charge portion, wherein the non-charging portion and the charge portion are separation members and are not contacted to each other.
    Type: Application
    Filed: December 8, 2011
    Publication date: June 14, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Nobuo Oshima, Takayuki Namiki
  • Publication number: 20120148308
    Abstract: A blade-like charging member for charging a surface of an image bearing member by contacting thereto includes a charging portion for effecting electric discharge to the surface of the image bearing member. The non-charging portion is made of a material having a higher resistance than that of the charging portion so as to prevent electric discharge between the non-charging portion and the surface of the image bearing member. The non-charging portion is capable of sliding contact with the surface of the image bearing member over the entirety of an image forming region width of the surface of the image bearing member, the charge non-charging portions are bonded to each other by adhesive material at a connection interface.
    Type: Application
    Filed: December 8, 2011
    Publication date: June 14, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Issei Imamura
  • Patent number: 8185000
    Abstract: An electrostatic charging apparatus, includes: an endless-shaped electrostatic charging belt having electrical conductivity, the electrostatic charging belt being arranged in a state of having a predetermined contact zone being in contact with a moving to-be-charged body and moving in the same direction as a moving direction of the to-be-charged body; and plural electrode members including at least a first electrode member and a second electrode member, the plural electrode members being provided inside the electrostatic charging belt, and the first and second electrode members being provided on both sides of the contact zone of the electrostatic charging belt in the moving direction thereof so as to press the electrostatic charging belt against the to-be-charged body and forming gaps that permit electric discharge between the to-be-charged body and the electrostatic charging belt, the gaps being adjacent to the respective sides of the contact zone of the electrostatic charging belt.
    Type: Grant
    Filed: November 4, 2008
    Date of Patent: May 22, 2012
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Taku Aoshima, Osamu Handa
  • Publication number: 20120082481
    Abstract: A charging member is provided which has a surface layer that can more surely keep bleeding from occurring. It is a charging member having a substrate, an elastic layer and a surface layer; the surface layer containing a high-molecular compound having a constituent unit represented by the following formula (1) and a constituent unit represented by the following formula (2), and having an Si—O—Zr linkage.
    Type: Application
    Filed: December 12, 2011
    Publication date: April 5, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Noriko Nagamine, Noriaki Kuroda
  • Publication number: 20120076539
    Abstract: A charging member is provided which can not easily change in charging performance even because of its service over a long period of time. The charging member has a conductive support, an elastic layer and a surface layer. The elastic layer comprises spherical particles in such a way that the spherical particles are exposed at least in part to the surface of the elastic layer so as to make the surface of the elastic layer roughened; the spherical particles are at least one type selected from the group consisting of spherical silica particles, spherical alumina particles and spherical zirconia particles; the surface of the elastic layer is overlaid with the surface layer in such a way that the surface profile of the elastic layer is reflected on the surface profile of the charging member; and the surface layer comprises a high-molecular compound having a specific constituent unit.
    Type: Application
    Filed: November 30, 2011
    Publication date: March 29, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Taichi Sato, Masaaki Harada, Yukinori Nagata, Toshiro Suzuki
  • Publication number: 20120070192
    Abstract: An electrostatic charging apparatus includes: an electrostatic charging member that has a discharge face causing discharge between the electrostatic charging member and a to-be-charged member having a charge retention part to hold a charge, and comes in contact with the to-be-charged member so as to charge upon the application of voltage; and an adjusting unit that adjusts an angle between the to-be-charged member and the discharge face.
    Type: Application
    Filed: January 31, 2011
    Publication date: March 22, 2012
    Applicant: FUJI XEROX CO., LTD.
    Inventor: Jin IWASAKI
  • Patent number: 8139984
    Abstract: An image forming apparatus, wherein a surface resistivity Rse[?] of a charger and a volume resistivity Rsw [?·cm] of the composition having a low softening point satisfy the following relationship: 0.8×10?1Rse<Rvw<1.5×10Rse is provided. The image forming apparatus contains a photoreceptor; a charger configured to charge the photoreceptor with a charger contacting thereto; an irradiator configured to irradiate the photoreceptor to form an electrostatic latent image thereon; an image developer configured to develop the electrostatic latent image with a toner to form a toner image on the photoreceptor; a transferer configured to transfer the toner image onto a recording material directly or through an intermediate transferer; and a fixer configured to fix the toner image on the recording material, wherein the toner comprises: a binder resin; a colorant; a composition having a low softening point; and an external additive.
    Type: Grant
    Filed: October 26, 2010
    Date of Patent: March 20, 2012
    Assignee: Ricoh Company, Limited
    Inventors: Hiroyuki Murakami, Masahide Inoue, Chiyoshi Nozaki, Tsuyoshi Nozaki, Atsushi Yamamoto, Takuya Kadota, Mitsuyo Matsumoto, Katsunori Kurose, Yoshimichi Ishikawa
  • Patent number: 8131185
    Abstract: A charging device includes a charging member and a charging power source portion. The charging member, in a sheet shape, is secured by contacting a region of an electrostatic latent image to be formed on a rotatable image carrier. The charging power source portion applies charging voltage to the charging member. The charging member includes a plurality of holes.
    Type: Grant
    Filed: May 26, 2009
    Date of Patent: March 6, 2012
    Assignee: Oki Data Corporation
    Inventors: Toshiharu Sato, Masahiro Kawano
  • Patent number: 8126380
    Abstract: An image forming apparatus includes a plurality of image forming units forming a visible image by attaching charged developer to an electrostatic latent image, a transfer belt member being transferred the visible image formed by each of the plurality of image forming units, a plurality of tension members tightly stretching the transfer belt member, a primary transfer member transferring the visible image formed by the plurality of image forming units to the transfer belt unit, a secondary transfer member transferring the visible image transferred to the transfer belt member on a recording medium, and a fixing unit fixing the visible image transferred to the recording medium. The plurality of image forming units are disposed in at least two transfer regions formed by segmenting the transfer belt member by the plurality of the tension members.
    Type: Grant
    Filed: September 24, 2008
    Date of Patent: February 28, 2012
    Assignee: Oki Data Corporation
    Inventors: Masahiro Kawano, Tatsuya Murakami, Yasunaga Yamaguchi
  • Patent number: 8126368
    Abstract: A charge device includes a charging belt, an electrode member, a bias supplying unit and a discharge region forming member. The belt comes into contact with a charged body. The electrode member is in contact with a part of an inner peripheral surface of the charging belt. The electrode member faces the charged body across the charging belt between the electrode member and the charged body. A downstream-side portion of the charging belt is located downstream of a position where the charged body faces the electrode member, in a moving direction of the charged body. The discharge region forming member brings the downstream-side portion into contact with the electrode member to form a discharge region in which discharge occurs between the downstream-side portion and the charged body.
    Type: Grant
    Filed: May 15, 2009
    Date of Patent: February 28, 2012
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Taku Aoshima, Osamu Handa
  • Publication number: 20120045251
    Abstract: A charging apparatus including a charging tube which has an outer surface contacting a photoconductive medium and electrically charges a surface of the photoconductive medium, a shaft which is disposed in the charging tube and to which a charging voltage is applied, and a conductive member which is connected to the shaft and contacts an inner surface of the charging tube. A friction coefficient between the conductive member and the inner surface of the charging tube may be less than a friction coefficient between the photoconductive medium and the outer surface of the charging tube, so that a slip phenomenon of the charging tube is prevented.
    Type: Application
    Filed: July 5, 2011
    Publication date: February 23, 2012
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: In-cheol Jeon, Ki-jae Do, Jong-hwa Joo, Yong-hoon Lee, Sang-jin Park
  • Publication number: 20110299890
    Abstract: The present invention provides an image forming apparatus, including: an image carrier configured by a positively charged single-layer electrophotographic photosensitive body; a charging device which is based on a contact charging method for charging a circumferential surface of the image carrier while making contact with the circumferential surface of the image carrier; and a transfer unit which transfers a toner image on the circumferential surface of the image carrier to a transfer receiving body by gripping the transfer receiving body with the image carrier, wherein the transfer unit includes an application unit to which a transfer bias is applied, and a region having a volume resistivity of 107 to 109 ?·cm exists between the image carrier and the application unit.
    Type: Application
    Filed: June 2, 2011
    Publication date: December 8, 2011
    Applicant: KYOCERA MITA CORPORATION
    Inventors: Yoshitaka Imanaka, Shinki Miyaji, Masaki Kadota, Masahito Ishino, Hiroka Itani
  • Patent number: 8066366
    Abstract: A release agent applicator applies release agent to an imaging drum and absorbs release agent metered from the drum to extend the operational life of an image drum maintenance unit. The applicator includes a reservoir for storing release agent, the reservoir having a plurality of perforations for enabling release agent to seep from the reservoir, a containment membrane for wicking release agent from the perforations of the reservoir, and a delivery layer for delivering release agent from the containment membrane to an imaging drum, the delivery layer having pores in a range of about 50 ?m to about 200 ?m.
    Type: Grant
    Filed: May 4, 2009
    Date of Patent: November 29, 2011
    Assignee: Xerox Corporation
    Inventors: Alexander J. Fioravanti, Paul J. McConville, James J. Padula, Michael Jon Levy
  • Patent number: 8041259
    Abstract: A conductive member includes a conductive supporting member provided facing an image bearing member and including a continuous or discontinuous fixing groove provided in the vicinity of each of both ends of the conductive supporting member in a peripheral direction thereof, an electrical resistance adjusting layer formed on the conductive supporting member and including a step portion which includes at least one step disposed in the vicinity of each of the both ends of the electrical resistance adjusting member, and gap retainers each provided to the step portion and including a cylinder portion which contacts at least one surface of the step portion, and an end plate so that a predetermined gap is formed between the image bearing member and the electrical resistance adjusting layer. The end plate contacts at least one surface of the step portion and fits into the fixing groove.
    Type: Grant
    Filed: May 9, 2008
    Date of Patent: October 18, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Yutaka Narita, Makoto Nakamura, Taisuke Tokuwaki, Tadaaki Hattori, Tadayuki Oshima, Hiroki Furubayashi
  • Patent number: 8032050
    Abstract: The charge assembly according to the present invention includes a charge member having a conductive support body on which a resistance adjusting layer and a surface layer covering the resistance adjusting layer are formed, to rotate a surface of the image support body to electrically charge the image support body, the surface layer having a static friction coefficient of 1.0 or more; and a cleaning member rotating the surface layer of the charge member in contact therewith to remove foreign particles on the surface layer.
    Type: Grant
    Filed: October 26, 2007
    Date of Patent: October 4, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Makoto Nakamura, Yutaka Narita, Tadayuki Oshima, Taisuke Tokuwaki, Hiroki Furubayashi
  • Patent number: 8005402
    Abstract: A technology capable of realizing a stable charging performance in an image forming apparatus employing a contact charging system is provided. A charging device is configured to have a charging member to which a prescribed bias voltage is applied and which comes into contact with an image carrying surface of an image carrier to charge the image carrying surface; and a particle supply section configured to supply a charging auxiliary particle made of a conductive particle having a diamond particle contained therein in a portion coming into contact with the image carrying surface in the charging member.
    Type: Grant
    Filed: January 10, 2007
    Date of Patent: August 23, 2011
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventors: Takeshi Watanabe, Masashi Takahashi, Mitsuaki Kouyama
  • Patent number: 7977020
    Abstract: An electrophotographic photoreceptor comprising laminating a monolayer type photosensitive layer containing a charge generation material and a charge transport material or a laminate type photosensitive layer obtained by laminating a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material in this order, on a conductive support, wherein the charge transport layer of the monolayer type photosensitive layer or laminate type photosensitive layer contains an enamine compound represented by the following formula (1).
    Type: Grant
    Filed: April 24, 2008
    Date of Patent: July 12, 2011
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takatsugu Obata, Akihiro Kondoh
  • Patent number: 7970319
    Abstract: A charging apparatus includes a charging member and at least one projection formed on the charging member. The charging member includes a surface that faces the surface of a photoconductive body. The at least one projection is formed on the first surface to extend in a direction parallel to the longitudinal direction of the photoconductive body. The projection is in contact with the surface of the photoconductive body.
    Type: Grant
    Filed: May 26, 2009
    Date of Patent: June 28, 2011
    Assignee: Oki Data Corporation
    Inventors: Masahiro Kawano, Yukiyoshi Oda
  • Patent number: 7970320
    Abstract: An image forming apparatus includes an image bearing member and a charging device configured to charge the image bearing member. The charging device includes a magnetic particle carrier and a magnetic particle regulating member configured to regulate magnetic particles carried by the magnetic particle carrier. The charging device causes the magnetic particles carried by the magnetic particle carrier to contact the image bearing member, and applies a voltage to the magnetic particle carrier to charge the image bearing member. An electrode has a contact area via which the electrode can contact magnetic particles stored in a particle pool defined by the magnetic particle carrier and the magnetic particle regulating member. The contact area is variable according to an amount of the magnetic particles stored in the particle pool. A current detection device detects a value of current flowing from the magnetic particle carrier to the electrode via the magnetic particles.
    Type: Grant
    Filed: December 18, 2008
    Date of Patent: June 28, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yukwi Hong, Koichi Hashimoto, Ryota Matsumoto, Shingo Horita, Ryo Nakamura
  • Patent number: 7945183
    Abstract: An image forming device includes: a high voltage generating circuit for applying an oscillating voltage to a charging member disposed in contact with or proximity to an image carrier, the oscillating voltage having a DC voltage Vdc and an AC voltage Vac superimposed thereon; a current detecting portion for detecting the value of a DC current Idc between the image carrier and the charging member; an AC voltage control portion for controlling the value of the AC voltage Vac so as to secure the detected value of the DC current Idc within a target current range; and an aging control portion for performing rotation driving of the image carrier while securing the AC voltage Vac and the DC voltage Vdc at preset voltage values and setting the frequency of the AC voltage Vac at a frequency different from a frequency during an image forming operation.
    Type: Grant
    Filed: October 1, 2008
    Date of Patent: May 17, 2011
    Assignee: Kyocera Mita Corporation
    Inventors: Norio Tomiie, Shinki Miyaji
  • Patent number: 7941077
    Abstract: A conductive member includes a conductive supporter, an electric resistance adjusting layer formed on the conductive supporter and gap retaining members which are of a different material from that of the electric resistance adjusting layer and are disposed respectively at both ends of the electric resistance adjusting layer for contacting an image carrier so as to maintain a predetermined gap between the electric resistance adjusting layer and the image carrier, wherein the electric resistance adjusting layer is made from a resin composition containing a thermoplastic resin containing an ether group, an organic phosphonium salt and a fluorine-containing organic anion salt.
    Type: Grant
    Filed: March 7, 2008
    Date of Patent: May 10, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Tadayuki Oshima, Hiroki Furubayashi, Taisuke Tokuwaki, Yutaka Narita, Makoto Nakamura
  • Publication number: 20110103837
    Abstract: A mechanism for electrifying a rotator that is used in an image forming apparatus includes a cloth-like or sheet-like conductive member, wherein part of the conductive member comes into contact with an object to be electrified and the other part of the conductive member comes into surface contact with any one contact member of the rotator, a rotating shaft that rotates together with the rotator, and a shaft where the rotator is rotatably supported, so that the object to be electrified and the contact member are electrically connected to each other through the conductive member.
    Type: Application
    Filed: October 26, 2010
    Publication date: May 5, 2011
    Inventors: Minoru Toyoda, Hirobumi Ooyoshi
  • Patent number: 7937035
    Abstract: An image forming apparatus including: a rotatable image-carrier; a charging unit that contacts and charges a surface of the image-carrier; an exposing unit that exposes the surface and forms a latent-image; a developing unit that develops the latent-image with a developer; a transfer unit that transfers a developed-toner-image onto a transfer-receiving member; a cleaning unit that is provided with a plate shaped cleaning member having a free end that faces upwards a corner portion of the free end contacting the surface, the cleaning member cleaning off developer remaining on the surface after transfer, and a developer pooling member provided between the cleaning member and the transfer unit, that temporarily pools the cleaned off developer at the free end; and a friction-coefficient reducing unit that reduces a friction-coefficient at the surface, and that reduces the friction-coefficient during non-image forming period to less than that during image forming period is provided.
    Type: Grant
    Filed: September 17, 2008
    Date of Patent: May 3, 2011
    Assignee: Fuji Xerox Co., Ltd
    Inventor: Akihisa Maruyama
  • Patent number: 7899352
    Abstract: An aspect of the invention provides a charging control device of a color image forming apparatus, and the charging control device can properly control a charging potential of an image bearing body such that fog and uneven density are not generated even in a low-temperature environment. The image forming apparatus includes a high-voltage generation circuit 91 which applies an oscillating voltage to the charging member 42 disposed in contact with an image bearing body 41, a direct-current voltage and an alternating-current voltage being superimposed to form the oscillating voltage; a current detection unit 92 which detects a direct current value passed from the charging member 42 to the image bearing body 41; and a voltage control unit 96 which controls the alternating-current voltage such that the detected direct-current value is maintained in a target current range. The image forming apparatus also includes an aging control unit 95 to perform running-in.
    Type: Grant
    Filed: February 28, 2008
    Date of Patent: March 1, 2011
    Assignee: Kyocera Mita Corporation
    Inventors: Norio Tomiie, Shinki Miyaji, Yoshihiko Maruyama
  • Patent number: 7890016
    Abstract: A charging apparatus includes a charging roller and a cleaning member. The charging roller charges a surface of an image bearing body. The cleaning member extends in a longitudinal direction parallel to the charging roller and that cleans the charging roller. The charging apparatus includes a bearing and a supporting member. The bearing supports a shaft of the charging roller. The cleaning member is mounted to the supporting member the cleaning member is held between the supporting member and the charging roller. The supporting member includes a surface to which the cleaning member is mounted, the surface being a curved surface configured to a circumferential surface of the charging roller. The supporting member includes a surface to which the cleaning member is mounted, the surface including a flat portion extending upstream with respect to rotation of the charging roller and a curved portion extending downstream.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: February 15, 2011
    Assignee: Oki Data Corporation
    Inventor: Atsushi Ota
  • Patent number: 7885579
    Abstract: There is provided a charging technique in which the generation of ozone is suppressed and charging efficiency can be improved. A charging device includes a contact unit configured to include a magnetic brush coming in contact with a body to be charged, the contact unit including, as a magnetic particle forming the magnetic brush, the magnetic particle containing at least a particle having a negative electronegativity, and a voltage application unit configured to negatively charge the body to be charged by applying a specified bias voltage through the magnetic brush in the contact unit to the body to be charged.
    Type: Grant
    Filed: November 8, 2006
    Date of Patent: February 8, 2011
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventors: Takeshi Watanabe, Masashi Takahashi, Mitsuaki Kouyama
  • Patent number: 7869743
    Abstract: An image forming apparatus in which a charging roller charges an image carrier to which a lubricant is applied prevents slip of the charging roller. The charging roller is composed of a metal core and a rubber layer mainly made of an epichlorohydrin rubber formed around the metal core. A surface of this rubber layer is hardened with a surface treating solution containing an isocyanate compound. The surface of this rubber layer is also subjected to three abrading processes including two stone grinding processes and one lapping process so that a ten-point height of irregularities Rz thereof becomes 11 ?m or more.
    Type: Grant
    Filed: April 24, 2007
    Date of Patent: January 11, 2011
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshiaki Kagawa, Kouji Shinkawa, Tohru Sakuwa
  • Patent number: 7867685
    Abstract: An image forming method, including charging a photoreceptor with a charger contacting thereto; irradiating the photoreceptor to form an electrostatic latent image thereon; developing the electrostatic latent image with a toner to form a toner image on the photoreceptor; transferring the toner image onto a recording material directly or through an intermediate transferer; and fixing the toner image on the recording material, wherein the toner includes a binder resin; a colorant; a composition having a low softening point; and an external additive, and wherein a surface resistivity Rse [?] of the charger and a volume resistivity Rsw [?·cm] of the composition having a low softening point satisfy the following relationship: 0.8×10?1Rse<Rvw<1.5×10Rse.
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: January 11, 2011
    Assignee: Ricoh Company, Limited
    Inventors: Hiroyuki Murakami, Masahide Inoue, Chiyoshi Nozaki, Tsuyoshi Nozaki, Atsushi Yamamoto, Takuya Kadota, Mitsuyo Matsumoto, Katsunori Kurose, Yoshimichi Ishikawa
  • Patent number: 7835655
    Abstract: A charger includes: a first charging member that contacts an image carrier and a second charging member that contacts the image carrier downstream from the first charging member. At the time of image formation, a voltage higher than the discharge start voltage of the first charging member is applied to the first charging member and a voltage lower than the discharge start voltage of the second charging member and lower than the voltage applied to the first charging member is applied to the second charging member, and at the time when an image is not formed, a voltage lower than the discharge start voltage of the first charging member is applied to the first charging member and a voltage higher than the discharge start voltage of the second charging member and higher than the voltage applied to the first charging member is applied to the second charging member.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: November 16, 2010
    Assignee: Seiko Epson Corporation
    Inventors: Masaru Kobashi, Koji Migita, Masashi Nakatsu, Shinichi Kamoshida
  • Publication number: 20100226684
    Abstract: A charging member is provided having a support, a conductive elastic layer formed on the support and a surface layer formed on the conductive elastic layer. The surface layer contains a polysiloxane having at least one of structures represented by the following formulas (1a1), (1a2), (1b1) and (1b2): Toners and external additives used in the toners clinging to the charging member surface can be minimized even through repeated use over a long period of time, thus the charging member can perform stable charging and image reproduction even when used in the DC contact charging method.
    Type: Application
    Filed: February 23, 2007
    Publication date: September 9, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Hiroshi Mayuzumi, Noriaki Kuroda
  • Patent number: 7787804
    Abstract: A charging member for electrically charging a substrate has a charge layer to be brought into contact with the substrate, an intermediate layer supporting the charge layer, and a support member supporting the intermediate layer. The intermediate layer has a first portion adjacent the charge layer and a second portion adjacent the support member, the first portion having a greater rigidity than that of the second portion.
    Type: Grant
    Filed: April 6, 2007
    Date of Patent: August 31, 2010
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventor: Masanori Yamamoto
  • Patent number: 7787799
    Abstract: The present invention provides an image forming device. The image forming device includes a photosensitive body, a charging roller, a cleaning member, and a controller. The charging roller, while rotating in a first direction, charges the photosensitive body for image formation. The cleaning member, formed by an elastic body, contacts the charging roller and cleans the charging roller. The controller, when the charging roller is not carrying out charging of the photosensitive body for image formation, rotates the charging roller in a direction opposite to the first direction.
    Type: Grant
    Filed: August 7, 2006
    Date of Patent: August 31, 2010
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hiroki Ando, Masayuki Kono
  • Publication number: 20100215403
    Abstract: An aspect of the present invention is a protective sheet including: a protective portion that can be inserted between a charging member which is in contact with an outer peripheral surface of a latent image carrier and the latent image carrier, and that can cover an image forming area formed on the outer peripheral surface of the latent image carrier; and a high friction portion that is connected to an end portion of the protective portion, that can be inserted between a pressing portion for being pressed against a background area formed on the outer peripheral surface of the latent image carrier and the background area of the latent image carrier, and whose dynamic frictional force when pulled out from the latent image carrier is higher than that of the protective portion.
    Type: Application
    Filed: August 26, 2009
    Publication date: August 26, 2010
    Applicant: FUJI XEROX CO., LTD.
    Inventor: Taku Aoshima
  • Patent number: 7756446
    Abstract: A pulse-like DC voltage is applied from two power sources to transfer residual toner uniformizing means and toner charge amount control means, respectively, to expel transfer residual toner deposited on these means from these means onto a photosensitive drum. In a low humidity environment, the number of application of the DC voltage is increased so as to sufficiently expel the transfer residual toner because the transfer residual toner is less liable to be expelled even when the pulse-like DC voltage is applied to the above two means in the low humidity environment in which an absolute moisture content in atmosphere is small and electrical resistances at portions of a photosensitive drum contacting the above two means.
    Type: Grant
    Filed: April 8, 2008
    Date of Patent: July 13, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tadanobu Yoshikawa
  • Patent number: 7732113
    Abstract: In an electrophotographic photosensitive member having a support, a conductive layer formed on the support, an intermediate layer formed on the conductive layer, and a photosensitive layer formed on the intermediate layer, the conductive layer has been formed by using a conductive layer coating fluid which contains TiO2 particles coated with oxygen deficient SnO2 having an average particle diameter of from 0.20 ?m or more to 0.60 ?m or less, and has a volume resistivity of from more than 8.0×108 ?cm to 1.0×1011 ?cm or less. The electrophotographic photosensitive member can keep charging lines from occurring.
    Type: Grant
    Filed: March 24, 2006
    Date of Patent: June 8, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazushige Nakamura, Hidetoshi Hirano, Hirotoshi Uesugi, Hirofumi Kumoi, Shinji Takagi, Yukihiro Abe, Junpei Kuno, Daisuke Miura
  • Patent number: 7725054
    Abstract: An electrifying apparatus, a processing unit including the electrifying apparatus, and an image formation apparatus including the electrifying apparatus. The electrifying apparatus includes a conductive sheet for electrifying at least one of a surface of a photoconductor and toner adhered to the surface. The conductive sheet is specified to have a pure-water contact angle equal to or greater than 108 degrees, and to have a shore D hardness equal to or less than 65.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: May 25, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Tetsumaru Fujita, Yoshio Sakagawa, Yuji Nagatomo
  • Patent number: 7711283
    Abstract: An image forming method and apparatus is disclosed. The method may include charging a rotating latent image bearing member with a rotating charger selected from at least one of contact chargers and short range chargers; irradiating the rotating latent image bearing member with imagewise light to form an electrostatic latent image on the latent image bearing member; developing the electrostatic latent image with a developer including a toner having a charge to form a toner image on the latent image bearing member; transferring the toner image onto a receiving material; and forming an electric field between the charger and the latent image bearing member after the toner image transferring such that charged materials present on the surface of the charger fly toward the latent image bearing member.
    Type: Grant
    Filed: June 27, 2006
    Date of Patent: May 4, 2010
    Assignee: Ricoh Company, Ltd.
    Inventor: Sadayuki Iwai
  • Patent number: 7711284
    Abstract: A cleaning device is disclosed which includes a cleaning member to clean the surface of a charging roll that charges an image carrier. The cleaning member is fixed at one end thereof and contacts at a free end side surface with the surface of the charging roll. The free end of the cleaning member is inserted in between the image carrier and the charging roll. Also disclosed is an image forming apparatus including the cleaning device.
    Type: Grant
    Filed: April 5, 2007
    Date of Patent: May 4, 2010
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Tomoya Ichikawa, Hideaki Ohike, Yusuke Kitagawa, Toshiyuki Matsui
  • Patent number: 7706724
    Abstract: A first bearing member and a second bearing member fit in a first side and a second side of a rotating shaft in the axial direction, respectively. The first bearing member is held by a supporting portion provided in a casing on a side corresponding to an emplacing member of an image carrier drum. The second bearing member is held by fitting in a fit-in portion from inside. A wall surface that regulates a charging roller in a longitudinal direction is formed on the second bearing member to protrude from a wall surface rotatably and pivotally supporting the charging roller.
    Type: Grant
    Filed: June 26, 2007
    Date of Patent: April 27, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshihiro Kawakami, Koji Kato, Hirobumi Ooyoshi, Tomofumi Yoshida, Kenzo Tatsumi, Yoshiyuki Shimizu, Tomohiro Kubota
  • Patent number: 7693455
    Abstract: A conductive member to be disposed so as to abut on an image carrier is provided. The conductive member includes an elongate conductive supporter, an electrical resistance adjusting layer formed on a circumferential surface of the supporter, and a pair of gap maintaining members provided respectively to the two ends of the adjusting layer. A gap with a certain clearance between an outer circumferential surface of the adjusting layer and an outer circumferential surface of the image carrier provided in parallel to the adjusting layer is formed. A stepped portion is formed in a joint section between the adjusting layer and each of the gap maintaining members with the joint section. An inclination is formed so as to be continuously inclined from the outer circumferential surface of each of the gap maintaining members to the outer circumferential surface of the adjusting layer in the stepped portion.
    Type: Grant
    Filed: August 10, 2007
    Date of Patent: April 6, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Taisuke Tokuwaki, Yutaka Narita, Toshio Kojima, Tadaaki Hattori, Makoto Nakamura, Tadayuki Oshima, Hiroki Furubayashi
  • Publication number: 20100074652
    Abstract: A charge device includes a charging belt, an electrode member, a bias supplying unit and a discharge region forming member. The belt comes into contact with a charged body. The electrode member is in contact with a part of an inner peripheral surface of the charging belt. The electrode member faces the charged body across the charging belt between the electrode member and the charged body. A downstream-side portion of the charging belt is located downstream of a position where the charged body faces the electrode member, in a moving direction of the charged body. The discharge region forming member brings the downstream-side portion into contact with the electrode member to form a discharge region in which discharge occurs between the downstream-side portion and the charged body.
    Type: Application
    Filed: May 15, 2009
    Publication date: March 25, 2010
    Inventors: Taku Aoshima, Osamu Handa
  • Patent number: 7684719
    Abstract: An image forming apparatus includes an image bearing member; a charging member for electrically charging the image bearing member through electric discharge by applying, to the charging member, a DC voltage biased with an AC voltage; and voltage condition determination means for determining a voltage condition during image formation on the basis of each of the values of AC currents obtained by applying a plurality of DC voltages biased with the AC voltages to said charging member.
    Type: Grant
    Filed: November 30, 2006
    Date of Patent: March 23, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventor: Kenichiro Kitajima
  • Patent number: 7664433
    Abstract: An image forming apparatus includes a charging device for charging a photosensitive element having a moving surface, by bringing a charging roller, to which voltage is applied, into pressure-contact with the photosensitive element, wherein to the charging member there is applied voltage for forming an electric field such that toner adhered to the charging roller surface at a non-image forming area is oriented towards the photosensitive element. The image forming apparatus is provided with pressure contact force modifying means for making the pressure contact force of the charging roller against the photosensitive element at the non-image forming area greater than that at an image forming area.
    Type: Grant
    Filed: January 29, 2008
    Date of Patent: February 16, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Tetsumaru Fujita, Yoshio Sakagawa, Yuji Nagatomo
  • Publication number: 20090324291
    Abstract: A charging device includes a charging member and a charging power source portion. The charging member, in a sheet shape, is secured by contacting a region of an electrostatic latent image to be formed on a rotatable image carrier. The charging power source portion applies charging voltage to the charging member. The charging member includes a plurality of holes.
    Type: Application
    Filed: May 26, 2009
    Publication date: December 31, 2009
    Applicant: Oki Data Corporation
    Inventors: Toshiharu Sato, Masahiro Kawano
  • Publication number: 20090324290
    Abstract: A charging apparatus includes a charging member and at least one projection formed on the charging member. The charging member includes a surface that faces the surface of a photoconductive body. The at least one projection is formed on the first surface to extend in a direction parallel to the longitudinal direction of the photoconductive body. The projection is in contact with the surface of the photoconductive body.
    Type: Application
    Filed: May 26, 2009
    Publication date: December 31, 2009
    Applicant: OKI DATA CORPORATION
    Inventors: Masahiro Kawano, Yukiyoshi Oda