Abstract: In an ink jet printer having a plural number of line heads arranged in a paper printing direction, it is sought to render the printing density high in the nozzle row direction without the need to exchange the line heads. The invention provides an ink jet printer in which line heads other than at least one of the line heads 3 are each displaceable by a distance that is equal to a part per the plural number of a nozzle pitch in the line head in a direction of the nozzle row.

Abstract: Fluttering of paper traveling opposite to and parallel to a nozzle width region of an ink jet head is held down, thereby improving the printing quality. An ink jet recording apparatus comprises an ink jet printer including printing units (7, 7?) whereby a sheet of paper (2) traveling in a paper passage in the form of an arch shaped by a plurality of guide rollers (12a-12h) is printed by a plurality of ink jet heads (6a-6d, 6a?-6d?). The ink jet heads of the printing units comprise ink jet heads of on-demand type having a plurality of nozzle rows of a nozzle width region in a direction of travel of paper. The paper passage opposite to nozzle faces of each ink jet head nozzle defined by two guide rollers (12a, 12b) positioned at an upstream and at a down-stream side in the direction of travel of paper, respectively.

Abstract: It is sought to allow a control unit part to be made up simply and at low cost, to prevent oozing out at an edge portion of a printing image and to enable inkjet printing at high quality regardless of kinds of the recording medium. To this end, there is provided a method of applying an undercoat in an ink jet recording apparatus of line type for printing recorded information, including an ink jet type undercoating unit for prior undercoating on a recorded information printing portion wherein undercoating data are prepared by software manipulation on the basis of printing information recorded data, characterized in that it comprises: laying a mask beneath a layer of a printing image and detecting an edge of the printing image; and on the basis of a mask information having the printing image extracted by software manipulation, applying an undercoat to an area covering from the printing image to an outer side of an edge portion of the printing image.

Abstract: An electrophotographic printer is configured such that an infrared heater is installed at a position between a plurality of electrophotographic print units installed in of the flow direction of a recording material, and a part (an inter-unit extension part) situated between print units of the recording material is irradiated with infrared light from the infrared heater to perform a partial evaporative removal of a carrier liquid of the recording material and a partial fixing of a toner.

Abstract: A wet type developing apparatus in which a liquid developer is fed onto a developing roller from a liquid developer supply roller immersed in the developing liquid within a liquid developer tank and an electrostatic latent image formed on a photoconductor drum is developed into a toner image by said developing roller is improved to enable the liquid developer to be kept fed at an appropriate amount of feed from the liquid developer supply roller onto the developing roller without air residual in the surface region of the liquid developer supply roller. The improvement comprises a partition plate disposed generally under the liquid developer supply roller within the liquid developer tank for partitioning the liquid developer tank into two in the direction of rotation of the liquid developer supply roller, the partition plate having its upper end juxtaposed with a peripheral surface of the liquid developer supply roller over its total axial length across a gap spacing between 0.05 and 0.5 mm.

Abstract: To remove a surplus carrier liquid after development on the surface of a photoconductor drum to obtain homogeneous printed images without being affected by an error in rotational accuracy of such as a carrier liquid removing roller, there is provided a wet type electrophotographic printer in which the carrier liquid removing roller 14 of a carrier liquid removing unit 8 is caused to come in rotational contact with the photoconductor drum 1 to remove a carrier liquid from the liquid toner image, thereby making a toner image for transfer onto a recording medium 7, the wet type electrophotographic printer being so configured that the carrier liquid removing roller in rotational contact with the photoconductor drum is urged against the latter under an urging force made adjustable; and a scraping blade 23 is brought into contact with the carrier liquid removing roller while being urged against the latter under an urging force made adjustable.

Abstract: It is desirable that the entire ink to be furnished to the nozzle head be deaerated efficiently, the entire ink including a portion of ink recovered from the purge section. Accordingly, an ink furnishing unit in an ink jet recorder is provided, which comprises a back pressure tank 15 connected to a nozzle head 2 via an ink supply passage, a main tank 9 connected to the back pressure tank via a main supply passage 16 provided with a main ink pump 18 therein, a recovery tank 7 connected to the main tank via a return passage provided with an ink pump 22 therein, and a purge cap 5 connected to the recovery tank via a recovery passage 8 provided with a purge pump 6 therein, the purge cap being opposed to the nozzle head when purging, wherein a deaerator 17 is disposed in the main supply passage connecting the main tank and the back pressure tank and the back pressure tank is connected to an upstream of the purge pump in the recovery passage via a three way directional control valve 30.

Abstract: An electrophotographic printer in which a photoconductor drum and a transfer drum can be supported in a simple component construction and in the makeup free from misalignment and development of thrust load.

Abstract: To allow continuous paper to be printed a plurality of times with a time difference by ink jet printer equipment and dried each time of printing while preventing condensation from occurring on an ink discharge surface of print head at and after the second time of printing, there is provided a printing apparatus comprising: a plurality of trains of printing units each of which has print heads arranged along a direction in which a continuous sheet of paper travels and which are arranged parallel to one another as shifted mutually in position in a direction of width of the continuous sheet of paper; a dryer section in which a plurality of continuous sheets of paper from the plural printing unit trains can travel as mutually shifted in position in a direction of width of the continuous sheet of paper; a cooling roller unit disposed downstream of the dryer section and having a cooling roller on which the plurality of continuous sheets of paper from the dryer section can be wound as mutually shifted in position in

Abstract: A electronic photograph printer includes a density-measurement section and a density controller section. The density-measurement section includes a density sensor 31 for measuring densities of images printed on a web by electronic-photograph-printing units. The density controller section adjusts densities of images which are about to be printed on the web by the electronic-photograph-printing units based on measurement data obtained by using the density sensor 31 associated with the densities of the image on the web. This configuration enables accurate and stable print-density control at a low cost.

Abstract: An ink jet recording apparatus in which a head supporting plate having a line head mounted thereon which comprises a plurality of short heads staggered is attached to a carriage whereby recording is performed by ink jet printing with the line head on a recording medium positioned beneath the carriage is rendered capable of using ordinary short heads.

Abstract: An ink jet recording apparatus in which a fabric as a recording medium is intermittently conveyed in an ink jet recording section is capable of printing an image on the fabric with precision and at high quality. The ink jet recording section of serial printing type includes a conveyer for intermittently conveying the fabric.

Abstract: A wet type developing apparatus is disclosed which can eliminate the need to provide a separately built cleansing unit and, moreover, makes it unnecessary to dismount a developer supply unit for its cleansing operation and to perform its subsequent re-mounting operation. The apparatus in which a developing roller 2 is in rotational contact with a rotating photoconductor drum 1 and an electrostatic latent image made on a surface of the photoconductor drum is developed with a liquid developer 6 supplied onto the developing roller from a developer supply roller 3 whose surface is in part immersed in the liquid developer reserved in a developer reservoir 5, includes a cleansing arrangement, comprising a unit or units 7 and/or 8, which is disposed at a site in the developer reservoir which is always immersed in the liquid developer for cleansing a portion of the developer supply roller which is immersed in the liquid developer.

Abstract: To meet with the requirement for high-speed printing with continuous paper used as its recording medium and to better clean a transfer roller surface in high-speed production as well, an electrophotographic printer is provided comprising: a carrier liquid supply unit 11 disposed at a portion of the circumference of a transfer roller 2 between a position of image transfer onto a recording medium 7 and a transfer roller cleaning device 12 and including a carrier liquid supply roll 13 in rotational contact with a surface of the transfer roller 2 for supplying a carrier liquid onto the surface of the transfer roller 2, wherein the transfer roller cleaning device comprises: a cleaning roll 17 rotating in rubbing contact with the surface of the transfer roller and having a bias voltage applied thereto which is of a polarity opposite to that of a residual toner; a peripheral surface scraping blade 18 positioned downstream of the cleaning roll in the rotation direction of the transfer roller and in contact with a per

Abstract: A toner fixing apparatus characterized by provision of a provisional fixing portion provided with a provisional fixing component having an infrared heater irradiating infrared radiation onto a printed surface of the web and a main fixing portion provided downstream in the web flow in the provisional fixing portion and nipping the web with heat rollers performing a main fixing operation or having a plurality of main fixing units. According to this invention, a toner fixing apparatus and an electrophotographic printing device including the toner fixing apparatus are provided which display excellent fixing properties during multicolor image formation, excellent heating efficiency and excellent economy with respect to installation space.

Abstract: To enable fabric of any length to be continuously printed without causing a textile printing unit to cease its operation, a textile printing method is provided in which fabric is conveyed by a conveyer belt and passed through a printing section to print on the fabric, the printing section having a textile printing ink jet printer disposed opposite the conveyer belt, wherein the printing section is continuously supplied with the fabric comprising a plurality of successive sheets of fabric, each sheet having a given length, such a sheet of fabric for supply into the printing section having a terminal end tied with a starting end of a sheet of a fabric for continuous succeeding supply in the state that the terminal and starting ends are in contact with each other.

Abstract: A developer feeder for wet developing apparatus having a developing roller rotationally engaged with a photoconductor drum and a feed roll in part immersed in a liquid developer and rotationally engaged with the developing roller for supplying the liquid developer onto the developing roller can be made to furnish the peripheral surface of the developing roller with the liquid developer even in thickness by using a plurality of feed rollers which are not mesh rollers but whose peripheral surfaces are smooth and which are arranged circumferentially of the rotational developing roller.

Abstract: An ink supplier for an ink jet recorder is provided. The ink supplier includes a recording head, a main ink reservoir, and a subsidiary ink reservoir connected to the main ink reservoir for replenishment with ink from the main ink reservoir. A position head of the ink liquid level in the subsidiary ink reservoir is maintained substantially constant relative to a printing head face of the recording head.

Abstract: An inkjet recording apparatus having a plurality of inkjet heads arranged along a paper conveyance line is disclosed, which is capable of collecting an ink mist efficiently without making the inkjet heads intricate in makeup.

Abstract: A electronic photograph printer includes a density-measurement section and a density controller section. The density-measurement section includes a density sensor 31 for measuring densities of images printed on a web by electronic-photograph-printing units. The density controller section adjusts densities of images which are about to be printed on the web by the electronic-photograph-printing units based on measurement data obtained by using the density sensor 31 associated with the densities of the image on the web. This configuration enables accurate and stable print-density control at a low cost.