Abstract: An electrophotographic toner containing: a fixing resin, a colorant, and wax. The wax at least contains hydrocarbon wax having a number-average molecular weight of not higher than 600, and polyethylene wax having a number-average molecular weight of not higher than 600, a melting viscosity of lower than 15 mPa·s at 140° C. and a crystallinity of lower than 95%. A ratio of the hydrocarbon wax to the polyethylene wax is in a range of from 1:10 to 2:1. A maximum of absorption peaks in a heat-up time absorption calorie curve in a DSC curve of the toner measured by a differential scanning calorimeter is at a temperature not higher than 75° C. An onset temperature in absorption of heat is not higher than 65° C.

Abstract: Electrostatic charge developing toner contains at least fixing resin, a coloring agent and wax. Wax having number average molecular weight of not higher than 600 is contained as a component of the wax. A volume average particle size of the toner is in a range of from 5 &mgr;m to 10 &mgr;m. Toner particles each having a particle size of not larger than 4 &mgr;m are contained by 10% or lower by number of the total number of toner particles.

Abstract: A perfecting press apparatus for forming images on both sides of a transfer medium. With respect to a transferring current Ipt of an image forming unit, current Ipc is made large which flows from a charge control instrument for controlling charge polarity of the toner on the transfer medium in the direction of the transfer medium. In particular, in the image forming unit causing retransfer, a de-charging light source is installed between the a developing device and a transferring device for canceling charges other than at a latent image part of an image carrier, so that the relationship between Ipt and Ipc is to be 3×Ipc≦Ipc≦6×Ipt, whereby the retransfer is suppressed to minimum for producing satisfied quality of image.

Abstract: A paper treating unit includes: a paper loading table for loading paper; a first paper aligning member that regulates position of the paper by sliding back and forth in the paper proceeding direction; a second paper aligning member disposed upstream of the first paper aligning member in the paper proceeding direction to regulate the position of the paper in the paper proceeding direction; a third paper aligning member disposed along the paper proceeding direction to regulate the position of the paper in a width direction perpendicular to the paper proceeding direction by sliding back and forth in the direction perpendicular to the paper proceeding direction; and a position detecting unit that detects the position of the first to third paper aligning members. The first and third paper aligning members are disposed independently of the paper loading table.

Abstract: An image forming apparatus includes: a first image forming unit having a first printing section for forming a first image on the paper; a second image forming unit having a second printing section for forming a second image on the paper; and a paper conveying unit for conveying the paper from the first image forming unit to the second image forming unit. Accordingly, two kinds of image can be formed employing one image forming apparatus. The first image and the second image may be formed using the same recording material (toner) or different recording materials (toners).

Abstract: An image formation apparatus for keeping secularly stable image quality for all image patterns if change in the charge amount of a developer caused by environment variation or over time or change in the photoconductor characteristic occurs in electrophotographic record apparatus. A test patch image formed on a photoconductor by a parallel electric field is detected by an image density sensor, the developing bias and the photoconductor surface potential are controlled so that the density detected by the image density sensor becomes constant, a test patch image formed on the photoconductor by a peripheral electric field is detected by the image density sensor with the control condition of the image density sensor maintained, and the light application amount in which an image area of a several-dot width adjacent a blank paper part is exposed to light is controlled so that the density detected by the image density sensor becomes constant.

Abstract: An ink jet print head includes pressure chambers, nozzles, and ink channels in a one-to-one correspondence. A diaphragm forms a side of each pressure chamber. The ink channels are formed in a restrictor plate. Piezoelectric elements are attached to the diaphragm and to a piezoelectric element fixing plate, which supports the piezoelectric elements. A housing of the head is formed with a common ink channel for supplying ink to the ink channels and an internal space into which the piezoelectric elements and the piezoelectric element fixing plate are at least partially inserted. A cover is provided for covering the piezoelectric element fixing plate. The cover is connected to the housing and is provided with an internal space large enough to maintain a gap between the cover and the piezoelectric element fixing plate.

Abstract: A print system having a first printer and a second printer being placed at the stage following the first printer, the first printer having a mark formation section for forming a register mark at a predetermined location of a web and the second printer having mark detector for detecting the register mark and a buffer plate being placed so that it can be advanced to and retreated from a web transport passage for giving a constant tension to the web comprises a controller for setting the buffer plate to a predetermined position during the period until the register mark is transported at a constant distance after passing through the mark detector.

Abstract: An ink jet print head includes pressure chambers, a diaphragm forming a side of the pressure chambers, stacked piezoelectric elements, a piezoelectric element fixing plate, and a housing. The stacked piezoelectric elements are attached to the diaphragm in a one-to-one correspondence with pressure chambers. The piezoelectric element fixing plate is fixedly attached to and supports the stacked piezoelectric elements. The housing includes a common ink channel portion that supplies ink to the pressure chambers. The piezoelectric element fixing plate and the stacked piezoelectric elements are disposed at least partially in the space defined by the diaphragm and internal side walls of the ink channel portion with a gap existing between the piezoelectric element fixing plate and the internal side walls.

Abstract: A sheet-position synchronizing signal is generated once each time a recording sheet is transported by a single-line worth of distance in a sheet feed direction. A print-driving signal and a refresh-driving signal are generated within a time interval of two successive sheet-position synchronizing signal. When the print-driving signal is applied to a piezoelectric element of a nozzle, then a print ink droplet is ejected, thereby a dot is formed on a recording sheet. On the other hand, when the refresh-driving signal is applied to the piezoelectric element, then a negatively-charged refreshing ink droplet is ejected. The refresh ink droplet refreshing ink droplet is deflected by an electric field and collected by a metal mesh without reaching the recording sheet.

Abstract: A laser control device includes a light amount varying section for varying the light exposure amount at plural levels is provided with a correction section for correcting the difference between the times to the peaks of laser outputs of print signals input to a laser control circuit. The turning on time of each print signal is corrected, whereby the difference between the times to the peaks of laser outputs of the print signals different in light exposure amount can be eliminated for correcting the difference between image print positions.

Abstract: In a printing apparatus in which a sheet handling device for conducting plural kinds of post processing is connected to a subsequent stage of an image forming device, a plurality of sheet feeding apparatuses disposed in the sheet handling device have a sheet residual amount detecting sensor and a sheet exhaustion detecting sensor. When the sheet residual amount detecting sensor detects that the number of sheets in an inserter is smaller than a predetermined number, the image forming device transports a sheet after it is confirmed by the sheet exhaustion detecting sensor that a sheet remains in the inserter.

Abstract: A film loader for the image forming apparatus has a film formed endlessly and a film frame for holding the film, wherein a guide member for attaching or detaching the film with respect to the film loading portion of the film frame is formed by a packaging member for use in transporting and storing the film.

Abstract: An ink jet print head 1 includes a laminated piezoelectric element 31. The piezoelectric element 31 is fixedly attached to electrodes 33 by electrically conductive adhesive 32. A flexible printed cable 16 is electrically connected to electrodes 35 by soldering. The stationary plate 15 is formed with through holes 36, which are filled with an electrically conductive filler 34. The filler 34 and the electrodes 33, 35 are formed of tungsten, and the electrodes 33, 35 are plated with gold.

Abstract: An electric photograph system for improving non-linearities of an exposing light intensity and an operating current at a low exposing level when performing analog printing operation. A range (saturable absorber) having a saturable absorbing characteristic is provided in a part of an optical path including a semiconductor laser as light source to improve the non-linearity of the operating current when the light intensity is weak. The saturable absorber may be made in the form of a non current injected area provided in a part of the semiconductor laser as the light source or a thin film layer provided partly in films coated on a facet of the semiconductor laser. Due to the provision of the saturable absorber, the light output power characteristic can exhibit its linearity in its low optical power range, the size of a printing dot can be arithmetically changed, and thus fine laser printing can be realized.

Abstract: A printing apparatus includes a print data correcting section for correcting print data and a selecting section for selecting a correction-method to be used in the print data correcting section. The selecting section is formed so that the correction method is selected according to a posttreatment way of a posttreatment apparatus for performing posttreatment on a print result of the printing apparatus.

Abstract: An ink composition for use in an on-demand inkjet printer capable of printing on plain paper at a recording rate of 10 ips or higher, which ink composition comprises at least a pigment and non-pigment components including at least water and a thickening agent and shows a weight loss ratio at 25° C. and 60 RH % for 30 minutes of 5 to 25% based on the total weight of the ink. Also disclosed is an on-demand inkjet recording process using the ink composition.

Abstract: An inkjet head having an ink flow path communicated with an ink chamber to an inkjet nozzle and having an orifice plate to which the nozzle is formed. An ink-philic layer is formed on the surface of the ink flow path, and an ink repellent layer is formed on the surface of the orifice plate where the nozzle is formed. The ink-philic layer is made of amorphous silica or inorganic polymer of colloidal silica bonded with a polymer of (SiOR), and the ink repellent layer contains a compound having perfluoropolyether chain and alkoxysilane residue as a terminal.

Abstract: A position where a transport amount regulation member is opposed to a developing roller is in an area wherein the magnetic flux density in the tangent line direction becomes 95% or less of the maximum value upstream in the developer transport direction from the position at which the magnetic flux density in the normal direction formed by two magnetic poles on both sides of the transfer amount regulation member on the sleeve roller surface of the developing roller becomes 0 gausses and is in an area wherein the magnetic flux density in the normal direction becomes 90% or less of the maximum value of the upstream pole in the developer transport direction.

Abstract: A printing apparatus comprises a conveyance mechanism for conveying a web to a transfer unit, and a tension generating mechanism for applying a tension to the web fed to the conveyance mechanism, wherein the tension generating mechanism comprises a tension generating roller for changing the tension to be applied to the web in accordance with the rotational position, a tension guide that is rotated in accordance with the magnitude of tension generated by the roller, a first sensor for sensing the rotational position of the tension guide, a second sensor for sensing the rotational position of the tension generating roller, and a driver for controlling the rotation of the motor in accordance with the outputs of the first and second sensors.