Having Applied Bias Patents (Class 399/240)
  • Patent number: 10838324
    Abstract: In one example, a developer roller for liquid electrophotographic printing includes a cylindrical metal inner core, a rigid conductive plastic outer core surrounding the inner core, and a compliant exterior surrounding the outer core.
    Type: Grant
    Filed: January 20, 2017
    Date of Patent: November 17, 2020
    Assignee: HP Indigo B.V.
    Inventors: David Sabo, Guang Jin Li, Stanley J. Kozmiski
  • Patent number: 9606475
    Abstract: The printing method includes the steps of (1) Transferring after charging a charged liquid developer dispersion from a surface of the first member optionally via the at least one further member to a substrate, wherein excess liquid developer dispersion remains present on the first member after the transfer; (2) Treating the excess liquid developer dispersion so as to facilitate its removal from the first member (3) removing, at least substantially, the treated excess liquid developer dispersion from the surface of the first member using a removal device, and (4) upon interrupting or terminating the printing, removing material adhered to the removal device.
    Type: Grant
    Filed: September 4, 2014
    Date of Patent: March 28, 2017
    Assignee: Xeikon IP B.V.
    Inventors: Werner Jozef Johan Op de Beeck, Wim Libaers, Lode Erik Dries Deprez
  • Patent number: 9535354
    Abstract: A conductive roller in which dripping of a water-based coating during the manufacture thereof is restrained, and a manufacturing method thereof. The conductive roller includes a shaft, at least one elastic layer formed on the outer periphery of the shaft and a surface layer formed on the outer peripheral surface of the elastic layer. The elastic layer is formed by using a coating for elastic layers containing a liquid absorbing agent, and the surface layer is formed by using a coating for surface layers. The method comprises forming an elastic layer by applying a coating for elastic layers containing a liquid absorbing agent on the outer periphery of the shaft and drying to form the elastic layer; and forming a surface layer by, after forming the elastic layer, applying a coating for surface layers on the formed elastic layer and drying to form the surface layer.
    Type: Grant
    Filed: December 15, 2010
    Date of Patent: January 3, 2017
    Assignee: BRIDGESTONE CORPORATION
    Inventors: Hirotaka Tagawa, Junichi Takano, Izumi Yoshimura, Daijirou Sirakura
  • Patent number: 9372444
    Abstract: A wet type developing apparatus is provided which allows printing in a quality that is stable at an increased printing speed and also with changes in physical property of a liquid developer. The wet type developing apparatus to this end includes a liquid developer feed pathway which comprises a developing roller 7 for feeding the liquid developer onto a photoconductor drum 3; an anilox roller 9 immersed in part in the liquid developer and driven to rotate in rotational contact with the developing roller; and a doctor blade 11 disposed in contact with a surface of the anilox roller for controlling the rate of drawing up of the liquid developer. The developing and anilox rollers have their peripheral surfaces moving in an identical direction and at an identical rate of movement in an area of their rotational contact.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: June 21, 2016
    Assignee: MIYAKOSHI PRINTING MACHINERY CO., LTD.
    Inventors: Hideo Izawa, Junichi Setoyama, Takao Namiki, Sumito Mera
  • Patent number: 8958722
    Abstract: An extractor separates a dispersoid (toner) and a dispersion medium (carrier liquid) from a liquid sample (liquid developer) containing the dispersoid and the dispersion medium and extracts these. The extractor has a first roller that carries a thin layer of the liquid sample containing the dispersoid and the dispersion medium on a circumferential surface thereof and rotates about a shaft. A separating member is in contact with the first roller and separates the dispersion medium from the thin layer carried on the first roller. A charger charges the dispersoid in the thin layer carried on the first roller at a position upstream of a contact position of the separating member with the first roller with respect to a rotating direction of the first roller. An electric field generator generates an electric field for causing the charged dispersoid to be attracted to the circumferential surface of the first roller.
    Type: Grant
    Filed: October 21, 2010
    Date of Patent: February 17, 2015
    Assignee: Kyocera Mita Corporation
    Inventors: Tomoyuki Oda, Tomohisa Soda, Hiroyuki Ueda
  • Publication number: 20140334837
    Abstract: A supply member of this wet type image forming apparatus has a surface rotating in a direction the same as a surface of a developer carrier at the same peripheral velocity at a portion abutting to the developer carrier. A control unit causes toner particles on the supply member to move to the developer carrier by providing a potential difference between the developer carrier and the supply member and controls an amount of toner particles on a latent image carrier by controlling electric power of a first charging member.
    Type: Application
    Filed: May 6, 2014
    Publication date: November 13, 2014
    Applicant: Konica Minolta, Inc.
    Inventor: Atsuto HIRAI
  • Patent number: 8862006
    Abstract: A wet-type image forming apparatus forms a toner image on an image carrier using liquid developer containing carrier liquid and toner dispersed therein. The apparatus includes: a developing member carrying the liquid developer to develop a latent image thereby forming the toner image on the image carrier; a charger for charging the liquid developer on the developing member according to a current applied on the charger; a measuring member for measuring a potential of the liquid developer charged by the charger; and a controller for controlling an amount of the liquid developer on the developing member, before the toner image is formed on the image carrier, by setting plural values of the current to be applied on the charger and controlling the amount of the liquid developer based on results of measurement of potentials of the liquid developer charged by the charger with the plural values of the applied current.
    Type: Grant
    Filed: March 12, 2012
    Date of Patent: October 14, 2014
    Assignee: Konica Minolta Holdings, Inc.
    Inventor: Atsuto Hirai
  • Publication number: 20140301755
    Abstract: A digital printing apparatus comprising a developing roller (102) and an image carrying roller (101); the developing roller (102) being arranged to transfer liquid toner (107) onto the image carrying roller (101) in accordance with a charge pattern; an upstream charger (111) upstream of an area (108) of rotational contact between the developing roller (102) and the image carrying roller (101); a downstream discharger (112, 122, 132) downstream of the area (108); a sensor (200) downstream of the area (108) to detect a property representative of the charge of a liquid toner residue; and a controller (210) to receive sensor data from the sensor (200) and to provide a control signal to control the downstream discharger.
    Type: Application
    Filed: April 3, 2014
    Publication date: October 9, 2014
    Applicant: XEIKON IP BV
    Inventors: Nick Horemans, William Constant Waterschoot, Wim Libaers, Lode Erik Dries Deprez, Jürgen Norbert Bart Devlieghere
  • Patent number: 8833254
    Abstract: A system comprises an electrophotographic subsystem, a transfer subsystem, an imaging member, and an inking subsystem. The electrophotographic subsystem comprises a photoreceptor, a charging subsystem, an exposure subsystem, and a development subsystem. In operation, the photoreceptor is charged areawise. An exposure pattern is formed by the exposure subsystem on the surface of the charged photoreceptor to thereby write a latent charge image onto the photoreceptor surface. The image is developed with an image defining material, such as a dampening fluid. The image defining material forms a negative pattern of the image to be printed. This negative image is then transferred to the reimageable surface. The negative image is then developed with ink. The inked image may be transferred to a substrate.
    Type: Grant
    Filed: July 12, 2012
    Date of Patent: September 16, 2014
    Assignees: Xerox Corporation, Palo Alto Research Center Incorporated
    Inventors: Janos Veres, David K. Biegelsen, Chu-heng Liu
  • Patent number: 8824931
    Abstract: Liquid marking agent development assemblies and liquid marking agent hard imaging methods are described. According to one aspect, a liquid marking agent development assembly includes a developer member comprising an outer surface and a charging assembly adjacent to the outer surface of the developer member, and wherein the charging assembly comprises at least one roller member configured to provide substantially an entirety of an electrical field relative to the developer member which electrical field is used to direct a plurality of ink particles of a liquid marking agent to the outer surface of the developer member and which ink particles upon the outer surface of the developer member are used to develop latent images upon an imaging member.
    Type: Grant
    Filed: May 29, 2009
    Date of Patent: September 2, 2014
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Eric G. Nelson, David Sabo, David Vejtasa
  • Patent number: 8693908
    Abstract: An image forming apparatus of the invention includes; a cleaning member that collects liquid developer by cleaning a developer carrier; a first transporting path that moves the liquid developer collected by the cleaning member; an oscillating member that applies vibration to the liquid developer transported from the first transporting path; a developer supply unit that stores the liquid developer transported from a first transporting mechanism; a second transporting mechanism that includes a second transporting path that transports the liquid developer stored in the developer supply unit to a developer storage in a developing unit; and a control unit that adjusts a toner charge current applied to the toner charging unit and controls vibration applied to the oscillating member on the basis of the adjusted toner charge current.
    Type: Grant
    Filed: January 17, 2012
    Date of Patent: April 8, 2014
    Assignee: Seiko Epson Corporation
    Inventors: Kazuhiro Nishiyama, Akihiro Gomi, Tsutomu Sasaki, Naotaka Higuchi
  • Patent number: 8660448
    Abstract: An image forming apparatus includes a photoreceptor, a developing apparatus, a developing bias supply power source, a control section for controlling a developing bias, a density sensor, and an arithmetic section. When an image density adjustment operation is performed, the arithmetic section determines a print-time developing bias in accordance with a detection result obtained by detecting, by the density sensor, a plurality of image density adjustment toner images formed by changing a developing bias. The print-time developing bias is set by the control section when printing is performed. also, In a case where a previous print-time developing bias falls within at least a low range of a predetermined range of the developing bias, the arithmetic section determines the print-time developing bias to a value between a reference developing bias for a target image density and the previous print-time developing bias.
    Type: Grant
    Filed: February 1, 2012
    Date of Patent: February 25, 2014
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masayuki Otsuka, Takashi Kitagawa, Motoyuki Itoyama
  • Patent number: 8588655
    Abstract: In a device or method to develop potential images of images to be printed, the potential images being generated on an intermediate image carrier using developer fluid having a charged toner and carrier fluid, developing with an applicator device the potential images, the applicator device directing the developer fluid across the intermediate image carrier. With the feed device the developer fluid is supplied to the applicator device, the feed device discharging excess developer fluid depleted of toner and that is not transferred to the applicator device. With a conditioning device the carrier fluid is taken from the applicator device and the taken up carrier fluid is discharged. With a cleaning device residual developer fluid remaining after development of the potential images is cleaned off of the applicator device and the residual developer fluid is supplied to a chamber arranged in the cleaning device.
    Type: Grant
    Filed: February 24, 2011
    Date of Patent: November 19, 2013
    Assignee: Océ Printing Systems, GmbH
    Inventor: Martin Berg
  • Patent number: 8538299
    Abstract: A wet type developing apparatus includes a set charger positioned opposite to a surface of the developing roller, a liquid developer applying device disposed at one of a position opposite to a surface of the developing roller and a position opposite to a surface of the cleaning roller, a first cleaning blade disposed in contact with a surface of the cleaning roller downstream of the area of rotational contact of the cleaning roller with the developing roller in the rotation direction of the cleaning roller, and a second cleaning blade disposed in contact with a surface of the developing roller downstream of the area of rotational contact of the cleaning roller with the developing roller in the rotation direction of the developing roller.
    Type: Grant
    Filed: May 4, 2011
    Date of Patent: September 17, 2013
    Assignee: Miyakoshi Printing Machinery Co., Ltd.
    Inventors: Hideo Izawa, Junichi Setoyama, Kotaro Harada
  • Patent number: 8467692
    Abstract: An image forming apparatus includes a developing section that includes a feed member having a groove, a developer carrier developing with liquid developer fed from the feed member, and a charging member charging the liquid developer carried in the developer carrier. An image carrier carries an image developed by the developing section. An optical sensor includes a light emitting section emitting light to the image developed in the image carrier. A first light receiving section receives light reflected from the image. A second light receiving section is disposed at a position different from that of the first light receiving section. A control section adjusts a developing bias applied to the developer carrier in response to an output signal of the first light receiving section, and controls a bias applied to the charging member by the output signals of the first and second light receiving sections.
    Type: Grant
    Filed: February 17, 2010
    Date of Patent: June 18, 2013
    Assignee: Seiko Epson Corporation
    Inventor: Masahiro Fukazawa
  • Patent number: 8457532
    Abstract: Electrophotographic printing apparatus and method of printing using electrophotographic printing apparatus, the apparatus comprising an image-forming member having a surface on which a latent electrostatic image can be formed and developed for transfer of the developed image to a substrate via an intermediate transfer member. The apparatus comprises a voltage supply for generating electric potential between the surface of the intermediate transfer member and the image-forming member such that the developed image formed on the surface of the image-forming member is transferred to the intermediate transfer member. A controller of the apparatus controls the voltage supply to adjust the electrical potential to affect the transfer of ink to the intermediate transfer member from the image-forming member. In this way, the apparatus can adjust for changes in the electrical properties of the intermediate transfer member.
    Type: Grant
    Filed: December 18, 2007
    Date of Patent: June 4, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Iian Frydman, Dror Kella
  • Patent number: 8290404
    Abstract: An electrophotographic printing apparatus may include an image-forming member having a surface on which a latent electrostatic image can be formed and developed for transfer of the developed image to a substrate and a developer for depositing ink including charged particles onto the surface to develop the latent image. The developer may include an ink bearing surface from which ink is transferred and a cleaner for removing ink from the ink bearing surface. The developer may further include an adjustable power system generating an electric potential between the ink bearing surface and the cleaner such that charged ink particles remaining on the ink bearing surface after the transfer of ink to the image-forming member are removed from the ink bearing surface through attraction to the cleaner. A controller may adjust the power system such that a desired electric potential between the ink bearing surface and the cleaner is achieved.
    Type: Grant
    Filed: October 12, 2007
    Date of Patent: October 16, 2012
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Shaul Raz
  • Publication number: 20120201555
    Abstract: An image forming apparatus of the invention includes; a cleaning member that collects liquid developer by cleaning a developer carrier; a first transporting path that moves the liquid developer collected by the cleaning member; an oscillating member that applies vibration to the liquid developer transported from the first transporting path; a developer supply unit that stores the liquid developer transported from a first transporting mechanism; a second transporting mechanism that includes a second transporting path that transports the liquid developer stored in the developer supply unit to a developer storage in a developing unit; and a control unit that adjusts a toner charge current applied to the toner charging unit and controls vibration applied to the oscillating member on the basis of the adjusted toner charge current.
    Type: Application
    Filed: January 17, 2012
    Publication date: August 9, 2012
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Kazuhiro NISHIYAMA, Akihiro GOMI, Tsutomu SASAKI, Naotaka HIGUCHI
  • Patent number: 8208825
    Abstract: An electrostatographic printing machine has a liquid toner supply chain incorporating at least a toner supply device (10), a metering roller (21) and a development member (31) and an image carrying member (41). An electrostatic charging device (33) acts onto the development member to impress an electrostatic charge onto the development member and to induce a voltage thereon with respect to a machine electrical common earth potential. The toner supply roller, the metering roller and the developer member are each electrically connected to the machine electrical common earth potential (37) via a respective voltage regulating or controlling means (25, 27, 35) to regulate or control induced voltages on each of the toner supply roller, the metering roller and the developer member.
    Type: Grant
    Filed: February 11, 2008
    Date of Patent: June 26, 2012
    Assignee: Xeikon IP BV
    Inventor: Minghua Mao
  • Patent number: 8204395
    Abstract: The invention provides a wet development device, wet development method and image forming apparatus having the device by which appropriate cleaning can be performed, the wear of the blade or developing roller can be reduced, and good images can be obtained without toner contamination even when the amount of toner for development or that of electric charge of the toner is changed for changing the density or gradation of image or type of paper. The toner in the developer is electrically charged to an arbitral charging amount by a discharging section and provided for the development and the charge of the toner is eliminated after development by that a discharging section is provided before cleaning the developer remaining on the developing roller and the output of the discharging section is appropriately controlled corresponding to the output of the discharging section.
    Type: Grant
    Filed: July 28, 2009
    Date of Patent: June 19, 2012
    Assignee: Konica Minolta Holdings, Inc.
    Inventor: Atsuto Hirai
  • Publication number: 20120148279
    Abstract: A wet-type image forming apparatus includes an image bearing member, a developer bearing member for bearing liquid developer containing toner and carrier liquid on the circumferential surface thereof, a bias applying unit for applying a developing bias to the developer bearing member, a first charging unit for charging the toner in the liquid developer to a first polarity before supplying the liquid developer to the image bearing member, and a second charging unit for reversely charging the toner in residual liquid developer remaining on the circumferential surface of the developer bearing member to a second polarity opposite to the first polarity after the development process. When VD denotes the developing bias and V0 denotes the surface potential of the residual liquid developer when the reverse charging is not performed, a surface potential V of the residual liquid developer after reverse charging satisfies the equation: 0.1?(VD?V)/(V0?VD)?1.0.
    Type: Application
    Filed: December 6, 2011
    Publication date: June 14, 2012
    Applicant: Kyocera Mita Corporation
    Inventor: Tomohisa Soda
  • Patent number: 8180237
    Abstract: An image forming apparatus and method charges and exposes a latent image carrier to form a latent image. Bias is applied to liquid developer on a developer carrier, and liquid developer collected by a developer carrier cleaning member is stored in a collected developer storing portion. The state of the collected liquid developer is determined based on a state of bias application or detected image data, and a stirring amount of a conveying member that stirs the collected liquid developer is controlled based on the determined state to improve a property of the collected liquid developer conveyed to a storing unit.
    Type: Grant
    Filed: March 23, 2009
    Date of Patent: May 15, 2012
    Assignee: Seiko Epson Corporation
    Inventors: Tsutomu Sasaki, Kazuhiro Nishiyama, Akihiro Gomi
  • Patent number: 8165503
    Abstract: An image forming apparatus includes a liquid developer holding member and a bias voltage applying unit. The liquid developer holding member includes a conductive core member and a dielectric layer provided on an outer circumference of the core member, and the dielectric layer includes a dielectric material and has at least one concave portion formed on a surface thereof. The at least one concave portion of the dielectric layer holds therein a liquid developer containing a solid developer dispersed in a carrier liquid.
    Type: Grant
    Filed: March 18, 2009
    Date of Patent: April 24, 2012
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Masataka Maeda
  • Patent number: 8116647
    Abstract: An image forming apparatus includes: a photoconductive drum; a developing roller carrying toner; a DC voltage application portion outputting a DC voltage to be applied to the developing roller, and receiving a feedback voltage; an AC voltage application portion applying an AC voltage to be applied to the developing roller; a detection portion detecting occurrence of electric discharge; a first resistor portion generating a feedback voltage that is fed to the DC voltage application portion; a second resistor portion connected between the DC voltage application portion and the AC voltage application portion, and having a switching portion with which conducting on and off are switchable; and a control portion controlling the switching portion, at the time of printing, to bring the second resistor portion into a conducting state and, at the time of electric discharge detection, to bring the second resistor portion into a non-conducting state.
    Type: Grant
    Filed: November 16, 2009
    Date of Patent: February 14, 2012
    Assignee: Kyocera Mita Corporation
    Inventors: Kensuke Fujihara, Tamotsu Shimizu, Ryota Maeda, Kouji Fujii, Tomoyuki Kikuta
  • Publication number: 20110274466
    Abstract: A wet type developing apparatus comprises a set charger positioned opposite to a surface of the developing roller, a liquid developer applying means disposed at one of a position is opposite to a surface of the developing roller and a position opposite to a surface of the cleaning roller, a first cleaning blade disposed in contact with a surface of the cleaning roller downstream the area of rotational contact of the cleaning roller with the developing roller in the rotation direction of the cleaning roller and a second cleaning blade disposed in contact with a surface of the developing roller downstream of the area of rotational contact of the cleaning roller with the developing roller in the rotation direction of the developing roller.
    Type: Application
    Filed: May 4, 2011
    Publication date: November 10, 2011
    Applicant: MIYAKOSHI PRINTING MACHINERY CO., LTD.
    Inventors: Hideo Izawa, Junichi Setoyama, Kotaro Harada
  • Publication number: 20110249990
    Abstract: A wet type developing apparatus is provided which allows printing in a quality that is stable at an increased printing speed and also with changes in physical property of a liquid developer. The wet type developing apparatus to this end includes a liquid developer feed pathway which comprises a developing roller 7 for feeding the liquid developer onto a photoconductor drum 3; an anilox roller 9 immersed in part in the liquid developer and driven to rotate in rotational contact with the developing roller; and a doctor blade 11 disposed in contact with a surface of the anilox roller for controlling the rate of drawing up of the liquid developer. The developing and anilox rollers have their peripheral surfaces moving in an identical direction and at an identical rate of movement in an area of their rotational contact.
    Type: Application
    Filed: April 5, 2011
    Publication date: October 13, 2011
    Applicant: MIYAKOSHI PRINTING MACHINERY CO., LTD.,
    Inventors: Hideo Izawa, Junichi Setoyama, Takao Namiki, Sumito Mera
  • Publication number: 20110103840
    Abstract: An extractor separates a dispersoid (toner) and a dispersion medium (carrier liquid) from a liquid sample (liquid developer) containing the dispersoid and the dispersion medium and extracts these. The extractor has a first roller that carries a thin layer of the liquid sample containing the dispersoid and the dispersion medium on a circumferential surface thereof and rotates about a shaft. A separating member is in contact with the first roller and separates the dispersion medium from the thin layer carried on the first roller. A charger charges the dispersoid in the thin layer carried on the first roller at a position upstream of a contact position of the separating member with the first roller with respect to a rotating direction of the first roller. An electric field generator generates an electric field for causing the charged dispersoid to be attracted to the circumferential surface of the first roller.
    Type: Application
    Filed: October 21, 2010
    Publication date: May 5, 2011
    Applicant: KYOCERA MITA CORPORATION
    Inventors: Tomoyuki Oda, Tomohisa Soda, Hiroyuki Ueda
  • Patent number: 7869721
    Abstract: A method (400) and apparatus (100) that detects carrier particles (130) in an electrophotographic device is disclosed. The apparatus may include an image carrying member (110). The image carrying member may have a first side (111) and have a second side (112) opposite from the first side. The image carrying member may be configured to operate in a direction of motion (115). The image carrying member may also be configured to transport an image on the first side. The apparatus may also include a magnet (120) coupled to the second side of the image carrying member. The magnet may have a length (122). The length of the magnet may be at an angle (124) of greater than zero and less than 90 degrees to the direction of motion of the image carrying member. The magnet may be configured to attract toner carrier particles transported on the image carrying member. The apparatus may also include a first sensor (140) coupled in proximity to the first side of the image carrying member and coupled in proximity to the magnet.
    Type: Grant
    Filed: July 7, 2008
    Date of Patent: January 11, 2011
    Assignee: Xerox Corporation
    Inventors: Michael D. Thompson, Paul W. Morehouse, Jr., Diane Foley
  • Publication number: 20100226687
    Abstract: An image forming method is provided, which includes: adjusting the amount of application of liquid developer to an image carrier from a developer carrier in response to an output signal of a first light receiving section obtained by emitting light to a first image carried in the image carrier; and adjusting a bias applied to a charging member which is disposed in the developer carrier in response to an output signal of a second light receiving section obtained by emitting light to a second image different from the first image carried in the image carrier.
    Type: Application
    Filed: February 17, 2010
    Publication date: September 9, 2010
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Masahiro FUKAZAWA
  • Publication number: 20100111553
    Abstract: A developing device includes a developer storage portion that stores a liquid developer including toner and carrier liquid. A first coating member rotates and coats the liquid developer stored in the developer storage portion. A second coating member contacts the first coating member and rotates in a direction opposite to that of the first coating member. A developer supporting body contacts the second coating member and rotates in the same direction as that of the second coating member. A contact member contacts the liquid developer coated on the second coating member by the first coating member.
    Type: Application
    Filed: October 29, 2009
    Publication date: May 6, 2010
    Applicant: Seiko Epson Corporation
    Inventors: Tsutomu SASAKI, Kazuma MIYAZAWA, Masahiro FUKAZAWA
  • Patent number: 7693461
    Abstract: A development unit for a printing device is described. An equalizing element is provided to minimize residual charges which cause ghosting. The equalizing element can, for example, be a roller or a blade positioned downstream of a cleaning nip between the cleaning roller and the development roller and charged to an electric potential which is substantially the same as an electric potential of the development roller. The equalizing element can alternatively, or in addition to being charged to perform equalization, operate to aid in charge residual charge dissipation on the development roller by blocking developer from reaching the development roller downstream of the cleaning roller.
    Type: Grant
    Filed: January 3, 2006
    Date of Patent: April 6, 2010
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Michael H. Lee, Boaz Tagansky
  • Publication number: 20100040387
    Abstract: The invention provides a wet development device, wet development method and image forming apparatus having the device by which appropriate cleaning can be performed, the wear of the blade or developing roller can be reduced, and good images can be obtained without toner contamination even when the amount of toner for development or that of electric charge of the toner is changed for changing the density or gradation of image or type of paper. The toner in the developer is electrically charged to an arbitral charging amount by a discharging section and provided for the development and the charge of the toner is eliminated after development by that a discharging section is provided before cleaning the developer remaining on the developing roller and the output of the discharging section is appropriately controlled corresponding to the output of the discharging section.
    Type: Application
    Filed: July 28, 2009
    Publication date: February 18, 2010
    Inventor: Atsuto Hirai
  • Patent number: 7664437
    Abstract: This invention relates to a developing unit for maintaining constant density in an electrophotographic imaging process. The developing unit has a developer roll, wherein the developer roll provides a surface and a first voltage is applied to the developer roll; a skive device, wherein the skive device is positioned in contact with the developer roll and a second voltage is applied to the skive device; a cleaning device for the developer roll, wherein the cleaning device is in contact with the developer roll; and an ink container, wherein the developer roll and the cleaning device are inside the ink container. It is preferred that a current measuring device is present to measure current flow between skive device and the developer, or a voltage meter is present to measure a voltage across a known resistor that is in series with the power supply to the skive device.
    Type: Grant
    Filed: May 16, 2008
    Date of Patent: February 16, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Truman F. Kellie, William D. Edwards
  • Publication number: 20090245875
    Abstract: An image forming apparatus includes a liquid developer holding member and a bias voltage applying unit. The liquid developer holding member includes a conductive core member and a dielectric layer provided on an outer circumference of the core member, and the dielectric layer includes a dielectric material and has at least one concave portion formed on a surface thereof. The at least one concave portion of the dielectric layer holds therein a liquid developer containing a solid developer dispersed in a carrier liquid.
    Type: Application
    Filed: March 18, 2009
    Publication date: October 1, 2009
    Applicant: BROTHER KOGYO KABUSHIKI KAISHA
    Inventor: Masataka MAEDA
  • Publication number: 20090232533
    Abstract: An image forming apparatus according to the present invention includes an image carrier, a charging section that electrically charges the image carrier, an exposure section that exposes the image carrier to light to form a latent image, a development section that develops the latent image by means of a liquid developer containing carrier and toner particles, a first squeezing roller that is held in contact with the image carrier carrying an image developed by the development section and adapted to bear a bias voltage Vs1 applied thereto, a second squeezing roller that is held in contact with the image carrier squeezed by the first squeezing roller and adapted to bear a bias voltage Vs2 applied thereto, and a transfer member that is held in contact with the image carrier squeezed by the second squeezing roller and adapted to receive the image transferred thereto, the absolute value of the bias voltage Vs1 and the absolute value of the bias voltage Vs2 showing a relationship of |Vs1|>|Vs2|.
    Type: Application
    Filed: March 4, 2009
    Publication date: September 17, 2009
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hiroshi TOYAMA, Ken IKUMA
  • Publication number: 20090142685
    Abstract: An image forming method including charging an image bearing member by applying combination of DC voltage and AC voltage with frequency of 6.5 to 8.5 cycle/mm; irradiating the image bearing member with light to form an electrostatic image; developing the electrostatic image with a developer including toner to form a toner image; transferring the toner image onto a receiving material; fixing the toner image; cleaning the image bearing member with a blade; then applying a lubricant to the image bearing member; and then spreading the lubricant with a spreading member countering the image bearing member. The toner includes toner particles granulated in an aqueous medium; and at least three kinds of external additives including a first particulate hydrophobic silica, a particulate hydrophobic titanium oxide and a second particulate hydrophobic silica respectively having BET specific surface areas of 20 to 40 m2/g, 40 to 80 m2/g, and 130 to 300 m2/g.
    Type: Application
    Filed: November 24, 2008
    Publication date: June 4, 2009
    Inventors: Tsuneyasu NAGATOMO, Toyoshi Sawada, Satoshi Kojima
  • Patent number: 7536137
    Abstract: A wet electrophotographic image forming apparatus detects color per print page and executes printing by turning on only the development bias of a developing unit to be used for printing. The wet electrophotographic image forming apparatus has a color detecting unit for detecting colors for developing the electrostatic latent images per print page; and a controller for selectively turning on and turning off development bias applied to developing rollers of the plurality of the developing units according to the colors detected by the color detecting unit.
    Type: Grant
    Filed: November 15, 2005
    Date of Patent: May 19, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Joong-gwang Shin
  • Publication number: 20090092418
    Abstract: A developing method includes a step of driving a developing roller to rotate and supplying liquid developer stored in a liquid developer container to the developing roller, a step of applying a bias to a toner charger to electrically charge the liquid developer supplied to the developing roller, a step of driving the developing roller to rotate so as to move the liquid developer electrically charged by the toner charger to a developing position and subsequently bringing the developing roller into contact with a latent image carrier electrically charged by a charger and a step of developing the latent image, holding the developing roller in contact with the latent image carrier.
    Type: Application
    Filed: October 8, 2008
    Publication date: April 9, 2009
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Hiroshi TOYAMA
  • Publication number: 20090052917
    Abstract: A disclosed image forming apparatus comprises: a conveying belt conveying a record medium attracted to the conveying belt using electrostatic force; a recording head for ejecting droplets on the record medium and forming an image; and a voltage waveform applying unit applying voltage waveforms, in which the shape of a positive waveform and the shape of a negative waveform are different, to the conveying belt so as to apply positive and negative electric charge thereto and generate the electrostatic force.
    Type: Application
    Filed: July 18, 2006
    Publication date: February 26, 2009
    Inventors: Seiichi Kogure, Shinji Imoto
  • Patent number: 7463851
    Abstract: In a method or device for transport of liquid developer to an image carrier element for electrophoretic digital printing, a developer unit is arranged adjacent to the image carrier element, the developer unit directing a liquid developer having toner particles to the image carrier element, the toner particles crossing over to the image carrier element corresponding to previously-generated potential images. A raster unit is arranged adjacent to the developer unit. The raster unit transports the liquid developer to the developer unit by use of a raster. An electrical voltage is applied between the raster unit and the developer unit in order to exert a targeted field effect on the toner particles in a direction towards the developer unit. A chamber scraper having a dosing scraper is arranged adjacent to the raster unit and having liquid developer having the toner particles which are already charged. From the chamber scraper the raster unit accepts the liquid developer via the dosing scraper.
    Type: Grant
    Filed: July 29, 2004
    Date of Patent: December 9, 2008
    Assignee: Oce Printing Systems GmbH
    Inventors: Martin Berg, Volkhard Maess, Martin Schleusener
  • Publication number: 20080226350
    Abstract: To provide a developing device capable of preventing the hysteresis phenomenon. The developer of the developing device contains a toner and a carrier. The toner and the carrier are charged to a polarity different from each other by frictional contact thereof. The developing device has a first conveyance member and a second conveyance member which faces an electrostatic latent image bearing body via the second region. An electric field forming device forms a first electric field between the first conveyance member and the second conveyance member to move the toner in the developer retained by the first conveyance member to the second conveyance member, and forms a second electric field between the second conveyance member and the electrostatic latent image bearing body to move the toner retained by the second conveyance member to an electrostatic latent image of the electrostatic latent image bearing body.
    Type: Application
    Filed: March 13, 2008
    Publication date: September 18, 2008
    Applicant: Konica Minolta Business Technologies, Inc.
    Inventors: Hiroshi Goto, Takuya Okada
  • Publication number: 20080219707
    Abstract: According to an embodiment, an image shift can be decreased by a photoconductor belt which has a photosensitive layer formed on the surface of a cylindrically formed belt, a pair of rollers which is placed to apply tension to a photoconductor belt, and rotates the photoconductor belt in a specified direction, a charger which is placed opposite to the surface of the photoconductor belt placed between the pair of rollers, and charges the photosensitive layer, a light source which forms a latent image on the charged photosensitive layer, a developing unit which supplies a developing solution to the photosensitive layer having a latent image, develop the latent image, and forms a toner image, and an absorbing roller which is placed on the backside of the photoconductor belt placed between a pair of rollers, and absorbs the photoconductor belt.
    Type: Application
    Filed: May 6, 2008
    Publication date: September 11, 2008
    Inventors: Hideki NUKADA, Yuko NOMURA
  • Publication number: 20080080883
    Abstract: A developing device includes an image carrier, a developer carrier, a biasing unit disposed upstream of a developing area, and a controller configured to control the biasing unit, and a cleaning member disposed downstream of the developing area to remove the liquid developing agent remaining on the developer carrier. A latent image held on the image carrier may be developed with the liquid developing agent, including charged toner and a carrier liquid, at the developing area where the developer carrier faces the image carrier. The controller causes the biasing unit to apply a first bias voltage to the surface of the liquid developing agent held on the developer carrier during developing, or a second bias voltage thereto during cleaning.
    Type: Application
    Filed: August 17, 2007
    Publication date: April 3, 2008
    Applicant: BROTHER KOGYO KABUSHIKI KAISHA
    Inventor: Keisuke Takahashi
  • Patent number: 7292810
    Abstract: An embodiment includes developing unit having a first developer roller and a second developer roller in contact with the first developer roller. The first developer roller is adapted to transfer developed liquid developer to the second developer roller, and the second developer roller is adapted to transfer the developed liquid developer to a photoconductor. An electrode is separated from the first developer roller by a gap. The gap is configured to receive undeveloped liquid developer from a reservoir remote from the developing unit so that the first developer roller does not pass through undeveloped liquid developer contained in a reservoir within the developing unit.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: November 6, 2007
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Christopher S. Tanner, Ziv Gilan
  • Patent number: 7242892
    Abstract: A wet type image forming apparatus forms an image in accordance with an electrophotographic imaging process using a developing solution containing a toner in a carrier solution. The image forming apparatus includes a developing roller that holds the developing solution thereon, the developing roller being electrically charged to attract a toner contained in the developing solution toward its surface, a photoconductive drum on which a latent image to be developed is formed, the photoconductive roller being arranged to contact the developing roller, a scraping blade disposed in contact with the developing roller, the scraping blade scraping off the developing solution that has not been consumed for developing from the surface of the developing roller, and a toner separator that separates the toner that has not been consumed for developing from the surface of the developing solution carrier before the developing solution is scraped off by the scraping blade.
    Type: Grant
    Filed: May 26, 2005
    Date of Patent: July 10, 2007
    Assignee: PENTAX Corporation
    Inventors: Hiroyuki Saito, Hidetaka Yamaguchi, Motohiro Maseki
  • Patent number: 7174119
    Abstract: A developing device for developing an electrostatic image formed on an image carrier, includes a liquid developing agent, wherein toner particles are dispersed in a liquid solvent, and wherein a viscosity of the liquid developing agent is in a range 100 mPa·s to 1000 mPa·s, inclusive, a developing container for containing the liquid developing agent, a developing agent carrier for carrying the liquid developing agent within the developing container to the image carrier, wherein the developing agent carrier is disposed so as to form a gap between the developing agent carrier and the image carrier; and a developing bias voltage power supply for applying a developing bias voltage, which superimposes a DC voltage component and an AC voltage component to the developing agent carrier, wherein a peak voltage of the AC voltage component is in a range of 0.5 kV to 2 kV, inclusive, and a frequency of the AC voltage component is in a range of 10 kHz to 12 kHz, inclusive.
    Type: Grant
    Filed: January 9, 2004
    Date of Patent: February 6, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yuji Sakemi
  • Patent number: 7079792
    Abstract: A developing unit includes a developing roller including a roller portion. The developing roller is rotatable while carrying a developing liquid on the roller portion. The developing unit also includes a voltage applying device that applies a voltage to the roller portion to form an electric field for development between the roller portion and an image carrier, whereby the developing liquid deposited on the roller portion is transferred to a latent image formed on the image carrier. The roller portion includes a volume resistivity ranging from 0 ?·cm to 107 ?·cm.
    Type: Grant
    Filed: May 17, 2005
    Date of Patent: July 18, 2006
    Assignee: Ricoh Company, Ltd.
    Inventor: Mie Yoshino
  • Patent number: 7024126
    Abstract: A developing unit maintains constant density in an electrophotographic imaging process. The developing unit has: a) a developer with a developing surface and a first voltage is applied to the developer; b) a depositor, wherein said depositor is positioned to maintain a gap with the developer and a second voltage is applied to the depositor; c) a cleaning device for said developer, wherein the cleaning device is in contact with the developer; and d) an ink container, wherein the developer, the depositor and the cleaning device are inside the ink container.
    Type: Grant
    Filed: March 22, 2005
    Date of Patent: April 4, 2006
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Truman F. Kellie, William D. Edwards
  • Patent number: 7020420
    Abstract: In a device and method for electrographic printing or copying, a latent image carrier is provided having a potential pattern corresponding to an image pattern. An applicator pattern is provided that carries a liquid layer of ink spaced from a surface of the latent image carrier by an air gap. A surface of the applicator element is provided with a structure with which detachment of droplets from the liquid layer is facilitated, the structure having a plurality of first areas having an increased electrical conductivity, a plurality of second areas that differ from a remaining surface based on a portion of surface energy, and a plurality of third areas formed as microscopic elevations. A force field is applied in the air gap to act on the liquid layer. By overcoming the air gap, droplets are transferred from the liquid layer on the surface of the latent image carrier by overcoming the air gap for inking a latent image to create an inked image.
    Type: Grant
    Filed: May 31, 2001
    Date of Patent: March 28, 2006
    Assignee: Oce′ Printing Systems GmbH
    Inventors: Martin Berg, Martin Schleusener, Volkhard Maess
  • Patent number: 6999701
    Abstract: A removal nip having a predetermined width is formed by a sweep roller pressurizing mechanism, which adjusts the length of a tension spring by rotating an adjustment screw, and adjusting the size of an energizing force of a sweep roller with respect to a photosensitive drum. A pressurizing mechanism similar to the sweep roller pressurizing mechanism is also provided in a developing roller, to adjust the energizing force of the developing roller, to thereby form a developing nip having a predetermined width.
    Type: Grant
    Filed: April 19, 2004
    Date of Patent: February 14, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Mie Yoshino, Tohru Nakano, Yusuke Takeda, Noriyasu Takeuchi, Tsutomu Sasaki, Tsuneo Kurotori