Abstract: An image forming apparatus includes an image bearing member, an endless moving member configured to receive the image thereon from the image bearing member, and a brush member that includes a fiber portion including a plurality of fibers arranged in a standing condition with respective fiber tips held in contact with an inner surface of the endless moving member. A supporting member is configured to support the fiber portion on a brush surface thereof. The brush member is configured to have a whole brush current value per unit area of the whole brush surface equal to or smaller than 2.5 ?A/cm2, and one of a maximum sectional current value per unit area of a portion of the whole brush surface equal to or smaller than 22.0 ?A/cm2 and a ripple of brush sectional current values less than 34%.

Abstract: A transfer apparatus includes an image bearing unit, a transfer member and a bias generator. The image bearing unit is configured and arranged to bear an image. The transfer member is arranged with respect to the image bearing unit to form a nip portion therebetween. The transfer member includes a substrate and an elastic member. The substrate has a recessed portion with an opening width of the recessed portion being larger than a width of the nip portion as measured in a moving direction of the transfer member. The elastic member is fixed in the recessed portion and wound around the substrate. The elastic member has a volume resistivity of 1×106 to 1×1011 ?·cm. The bias generator is configured and arranged to apply a bias electric field to the nip portion.

Abstract: The present invention provides a transfer charger which provides an intermediate transfer belt with a sufficient transfer efficiency, does not wear in contact with an inner surface of the intermediate transfer belt, has a low frictional property, and is excellent in its friction stability and an image-forming apparatus. A transfer charger (62) is mounted inside the image-forming apparatus where a toner image held on an image holder (12) is transferred to an intermediate transfer belt (31) to obtain an image. The transfer charger (62) makes a surface contact with an inner surface of the intermediate transfer belt (31), with the transfer charger (62) being pressed toward the image holder (12) owing to a pressing member (61). The transfer charger (62) is a sheet material consisting of a resin composition containing 100 parts by weight of non-injection-moldable ultra-high-molecular-weight polyethylene resin, 2 to 15 parts by weight of electrically conductive carbon, and 0.

Abstract: Printed images exhibiting a color medium are applied to the printing substrate by a printing device, the printing substrate having been provided beforehand with a viscous fluid film by an application unit arranged in front of the printing device. The color medium of the printed images migrates to a surface of the viscous fluid film and adheres there. After the drying of the fluid film the printed images are firmly fixed on the printing substrate.

Abstract: A level determination circuit 60 determines whether a voltage level Vref of an output variable signal is a previously set reference level Vref?m or higher. According to this determination result, a constant voltage output circuit 70 and a constant current output circuit 80 selectively operate. The constant voltage output circuit 70 outputs a transfer voltage Vout of a level corresponding to the voltage level Vref of the output variable signal. The constant current output circuit 80 outputs a constant current Iout of a level corresponding to the voltage level Vref of the output variable signal.

Abstract: An image forming apparatus includes a first image carrying member for carrying a first toner image; a second image carrying member for carrying a second toner image in a maximum amount, of the second toner image carried on the second image carrying member, larger than a maximum amount of the first image carried on the first image carrying member; a first transfer member for electrostatically transferring the first toner image onto a transfer medium in a first transfer nip formed by bringing the transfer medium into contact with the first, image bearing member; and a second transfer member for electrostatically transferring the second toner image onto the transfer medium in a second transfer nip formed by bringing the transfer medium into contact with the second bearing member so that a length of the second transfer nip with respect to a movement direction of the transfer member is longer than a length of the first transfer nip with respect to the movement direction.

Abstract: By using an intaglio plate for holding a pattern formed by a developing agent, a transfer device for transferring patterns developed on the intaglio plate to a transfer object medium, and a baking chamber for eliminating an electrode layer after transfer or heightening resistance thereof, the patterns developed on the intaglio plate are transferred onto the electrode layer disposed at the opposite side of the transfer object medium, and then heated in the baking chamber, whereby the electrode layer is eliminated or heightened in resistance.

Abstract: A transfer arrangement is used in a transfer portion of an image forming apparatus. The transfer arrangement includes an electrically conductive member that contacts a toner image bearing member of the image forming apparatus. The electrically conductive member is made of polyurethane resin to which electrically conducive polymer is added. An adding amount of the electrically conductive polymer with respect to the polyurethane resin is from 8 wt % to 40 wt %.

Abstract: A method of preparing toner, the method including preparing a latex for a core by polymerizing a composition for a core including a macromonomer having a hydrophilic group, a hydrophobic group and at least one reactive functional group, at least one polymerizable monomer, and a wax; agglomerating the latex for a core by adding a pigment dispersion dispersed by the macromonomer and an inorganic salt to the prepared latex for a core; and coating the agglomerated latex for a core using a latex for a shell layer, wherein the latex for a shell layer is prepared by polymerizing a composition for a shell layer including at least one polymerizable monomer, a macroinitiator having polydimethyl siloxane units, and a macromonomer, and toner prepared according to the method.

Abstract: A color image forming apparatus including tandem type image forming units that form images of different colors, respectively. The image forming units form test marks of different colors on a conveyor belt in its conveying direction at predetermined intervals. The test marks include linear position displacement detecting test marks and density detecting test marks. Each of the linear position displacement detecting test marks extends in a direction perpendicular to the conveying direction of the conveyor belt, and each of the density detecting test marks includes an area having a predetermined density and being adjacent to each of the linear position displacement detecting test marks. A detection operation for detecting position displacements of the linear position displacement detecting test marks in a sub-scanning direction of the conveyor belt and a detection operation for detecting densities of the density detecting test marks are performed, based on detection signals output from sensors.

Abstract: A method and apparatus for determining the lateral position of a moving sheet in a sheet registration system. A side edge sensor is moved from a known location until the side edge of the moving sheet is detected. A signal is generated indicative of the position of the side edge when it is detected. The position of the side edge as indicated by the signal is used along with skew of the sheet to determine the lateral position of the sheet.

Abstract: There is a charge member which charges secondary transfer remaining toner on an intermediate transfer member to a polarity opposite to a normal charge polarity. The transfer remaining toner charged by the charge member is moved in the direction opposite to that of normal toner by a transfer bias and moved from the intermediate transfer member onto an image bearing member. A BK station is arranged on the downstream of other stations. In a continuous BK monochromatic mode, by applying a reverse bias to transfer portions of the other stations and applying the transfer bias only to the BK station, waste toner can be collected into the BK station (simultaneously with the transfer). In a full-color mode, since each transfer bias is applied to all stations, the waste toner is collected into the station on the uppermost stream.

Abstract: In an image forming apparatus, a transfer brush with length of raised bristles on the surface of a metal holder equal to or smaller than 5.8 millimeters is used. Alternatively, a transfer brush with a maximum bristle inclination amount of raised bristles in a brush unit including a plurality of bristles equal to or smaller than 0.53 millimeter or a transfer brush with a maximum bristle inclination return amount of raised bristles in the brush unit equal to or smaller than 0.30 millimeter is used. An amount of biting into a paper conveyor belt in the brush unit is set to a value equal to or smaller than 2.5 millimeters. A paper conveyor belt with hardness of the rear side equal to or lower than 78 Hs is used. Alternatively, a paper conveyor belt with a coefficient of static friction on the rear surface equal to or lower than 0.75 is used.

Abstract: An image forming apparatus includes an image bearing member for carrying a toner image; a transfer member for cooperating with the image bearing member to form a nip to transfer a toner image from the image bearing member onto a transfer medium nipped by the nip; transfer voltage applying means for applying a transfer voltage to the transfer member to transfer the toner image; detecting means for detecting a current when a monitor voltage is applied to the transfer member or a voltage when a monitor current is applied; transfer voltage determinating means for determining the transfer voltage on the basis of a detection result of the detecting means so that current through the transfer member in a transfer operation is the target current; and target current adjusting means for adjusting the target current so that target current when a resistance of the transfer member is relatively small is larger than the target current when the resistance value of the transfer member is relatively large.

Abstract: An image transfer member, an image transfer device and an image forming system employing the image transfer member and device are disclosed. The image transfer member comprises a base layer, and a surface layer formed from a semi-conductive material above the base layer to receive the developer image transferred from the photoconductor. The surface layer forms a contact inscribed angle ? in the range of 10° to 50° between the surface thereof and the developer image. The image transfer member has a voltage-current characteristic exhibiting a current density (CD) in the range of 0.6 ?A/cm2?CD?1.5 ?A/cm2 at 1 KV voltage, and a voltage decay characteristic exhibiting a voltage decay time (DT) in the range of 0.4 sec?DT?3 sec for the voltage decay from 500 V to 100 V. The present invention avoids a transfer defect such as transfer void produced by breakdown caused when a high bias voltage is applied to a developer image having a high electric charge and to significantly improve the transfer efficiency.

Abstract: The purpose of the present invention is to provide a method for transferring a pattern of a circuit pattern precursor formed of electroconductive particles containing no resin component onto an objective substrate with high transfer efficiency while retaining a pattern shape. A method of transferring the circuit pattern precursor formed from an conductive particle dispersed solution on a dielectric thin film body includes the steps of: temporarily removing a liquid film remaining around the circuit pattern precursor right after a development step; subsequently re-electrifying the electroconductive particle pattern by supplying a solvent again to the circuit pattern precursor; and then electrostatically transferring the pattern onto the objective substrate through electrophoresis in the solvent.

Abstract: An image forming apparatus may include: a photoreceptor and a corona charging device or bias transfer roller that provides a charge to an image receiving medium. A cover may be disposed over a portion of the corona charging device or the bias transfer roller to shield the photoreceptor from exposure to the charge from the corona charging device when image receiving medium is charged and in contact with the photoreceptor.

Abstract: An image transfer device includes an image transfer electrode roller which is disposed face to face with a photosensitive drum with a printing sheet passing between the image transfer electrode roller and the photosensitive drum. The image transfer device is structured such that the image transfer electrode roller can be shifted back and forth along a transport direction of the printing sheet. A voltage is applied to the image transfer electrode roller to create an image transfer electric field between the image transfer electrode roller and the photosensitive drum for transferring a toner image formed on the photosensitive drum onto the printing sheet. The image transfer electrode roller is brought to one of different positions along a transport direction of the printing sheet selected according to information on properties of the printing sheet and transfers the toner image onto the printing sheet at that position.

Abstract: Transfer roller(s) is/are such that either end thereof is formed from fibrous electrically conductive component(s) and such that cylindrical portion(s) in central region(s) is/are, for example, formed from metal roller-like structure(s), either fibrous electrically conductive component outer end being arranged so as to extend somewhat beyond either transfer/transport belt side. Furthermore, outside diameter(s) approximated by tips of respective individual fiber(s) of fibrous electrically conductive component(s) is/are somewhat larger than diameter(s) of metal roller-like structure(s). This makes it possible for electric field(s) to be applied, and for charging to occur, along the full width(s) of transfer/transport belt(s).

Abstract: The image forming apparatus has an image bearing member for bearing a toner, a transfer device which forms a transfer area in cooperation with the image bearing member for transferring the toner on the image bearing member onto a recording material, a charge elimination device which is opposed to the recording material at an upstream side of the transfer area in a conveying direction of the recording material thereby eliminating a charge on the recording material, and a control device which controls the recording material so as to form a loop in a position opposed to the charge elimination device, wherein the recording material forms a loop by the control device thereby approaching to the charge elimination device.

Abstract: A laser printer includes a photoreceptor drum, a transfer roller contacting the photoreceptor drum, a transfer roller frame holding the transfer roller, an outer frame holding the transfer roller frame, a diselectrification brush fixed to the transfer roller frame, and a spring at least having a surface formed of conductive material for biasing the transfer roller toward the photoreceptor drum. The spring is formed of a single member and has a first extension contacting the diselectrification brush and a second extension contacting the outer frame.

Abstract: A color image forming apparatus is described, which makes highly durable image transferring possible.

Abstract: The present invention provides an electrophotographic lamination film which can be easily laminated by using the film as it is without significantly modifying a conventional electrophotographic device, can be printed with letters of high resolution directly on a surface of the film capable of softening at relatively low temperatures, and can form an image of high quality having sufficient heat resistance and light resistance with good recognizability even in outdoor use, as well as a method of producing the same and a method of forming an image. In the electrophotographic lamination film, a surface resistance of at least one surface of a substrate thereof is in a range of 108 to 1013 ?/?, and a Vicat softening temperature of the substrate is in a range of 70 to 130° C.

Abstract: An electrophotographic printing device with a developer unit and a photoconductor. The photoconductor is either directly connected to a substrate to be printed in the region of a transfer zone, or is connected by an intermediate circuit of one or several transfer media. At least one charger is provided for the substrate and the substrate may be transported through the transfer zone by a transport device. According to this invention, an effective transfer of toner to the substrate surface can be achieved with such an arrangement, even with a poor electrically-conducting and thick-walled, sheet-like substrate, whereby a charger is arranged as the primary charger in the transport direction and a secondary charger is arranged in the region after the transfer zone and both primary and secondary chargers affect the surface of the substrate to be printed.

Abstract: The present invention relates to a charging member for charging a surface of a member to be charged in an image forming apparatus, and one aspect of the present invention provides a charging member having an outermost surface layer containing a conductive elastic material. The conductive elastic material comprises a polymer including a polar polymer, primarily including (i) acrylonitrile butadiene rubber, (ii) an ethylene oxide-propylene oxide-allyl glycidyl ether terpolymer, and (iii) a homopolymer of epichlorohydrin. The weights x, y and z of the components (i), (ii) and (iii), respectively, have a relationship of 0.2<y/(x+y+z)?0.5 and 4<y/z?20. This charging member can realize uniform charging and is small in resistance variation, even when used for a long time.

Abstract: A voltage adjusting thin plate 16 is arranged below a roller before transfer 7 so as to be abutted on a surface of the roller before transfer 7 at a side opposite to a side where a transfer wire 18 of a transfer device 9 is located. A paper powder removing thin plate 17 is arranged at a lateral side of the roller before transfer 7 so as to be abutted on a surface of the roller before transfer 7 at the same side as a side where the transfer wire 18 of the transfer device 9 is located. A bias voltage whose polarity is the same as a polarity of toner is applied to the voltage adjusting thin plate 16 only for a desired period, at least, just after the image forming apparatus 1 is activated and while application of voltage to the transfer device 9 is being stopped. As materials of the voltage adjusting thin plate 16 and the paper powder removing thin plate 17, preferably two-axial extensible polyester film is used.

Abstract: An image forming apparatus having a uniform nip between a photosensitive body and a transfer body. The image forming apparatus has a photosensitive unit on which an electrostatic latent image is formed, a developer feed unit to feed a developer onto the electrostatic latent image to form a visible image, and a transfer unit. The transfer unit has a curved side of a semi-hollow tubular shape that contacts the photosensitive unit, and a planar side opposite the curved side and secured at a support member, to transfer the visible image formed on the photosensitive unit to a recording medium. The curved side of the transfer unit has a uniform radius of curvature in an axial direction. Accordingly, the image forming apparatus can not only maintain a constant nip in relation to electrical resistance and contact pressure, but can also adjust the electrical resistance of the transfer unit by appropriately setting factors such as volume resistivity of the conductive elastic member.

Abstract: An object of the present invention is to provide an image forming apparatus that has an image bearing body for bearing a toner image, a conveying member for bearing and conveying a recording material, and a transferring member for transferring a toner image on the image bearing body to the recording material conveyed by the conveying member by the application of a voltage, wherein the transferring member has ion conductivity.

Abstract: A voltage adjusting thin plate 16 is arranged below a roller before transfer 7 so as to be abutted on a surface of the roller before transfer 7 at a side opposite to a side where a transfer wire 18 of a transfer device 9 is located. A paper powder removing thin plate 17 is arranged at a lateral side of the roller before transfer 7 so as to be abutted on a surface of the roller before transfer 7 at the same side as a side where the transfer wire 18 of the transfer device 9 is located. A bias voltage whose polarity is the same as a polarity of toner is applied to the voltage adjusting thin plate 16 only for a desired period, at least, just after the image forming apparatus 1 is activated and while application of voltage to the transfer device 9 is being stopped. As materials of the voltage adjusting thin plate 16 and the paper powder removing thin plate 17, preferably two-axial extensible polyester film is used.

Abstract: In an image forming apparatus having an image forming portion for forming an image on an image bearing member, a transferring portion provided with a transferring member capable of contacting with the image bearing member and a voltage applying portion for applying a voltage to the transferring member, and for electrostatically transferring the image on the image bearing member to a transferring medium, an electric current detecting portion for detecting an electric current flowing to the transferring member, and a control portion for performing an electric current detecting operation of detecting an electric current flowing when the voltage applying portion applies a predetermined voltage before an image transferring operation by the electric current detecting portion, and determining a transfer voltage applied to the transferring member during the image transferring operation on the basis of a result of the detection by the electric current detecting operation, the electric current detecting operation is pe

Abstract: An image forming apparatus that prevents adverse effects caused by a transferring device on image formation while no high voltages are being applied to a transferring device includes a transferring device that transfers a developed image resting on an image carrier, to a medium, a high-voltage power supply that applies a high voltage to the transferring device, and a disabling device that disables a flow of current through the transferring device while the high-voltage power supply is not applying any high voltage to the transferring device.

Abstract: A printer includes a photosensitive member having a surface for forming a toner image and a transfer unit for transferring the toner image onto a recording paper. The transfer unit includes a transfer member arranged to face the recording paper for passing a transfer current, a discharge member arranged downstream from the transfer member in the recording paper transport direction to face the recording paper for passing a discharge current for performing discharge of the recording paper, a first guide arranged upstream from the transfer member in the recording paper transport direction for guiding the recording paper, and a second guide arranged downstream from the first guide in the recording paper transport direction for guiding the recording paper. The second guide includes a contact portion located between the transfer member and the discharge member in the recording paper transport direction for contact with the recording paper.

Abstract: An electrophotographic printing device with a developer unit and a photoconductor. The photoconductor is either directly connected to a substrate to be printed in the region of a transfer zone, or is connected by an intermediate circuit of one or several transfer media. At least one charger is provided for the substrate and the substrate may be transported through the transfer zone by a transport device. According to this invention, an effective transfer of toner to the substrate surface can be achieved with such an arrangement, even with a poor electrically-conducting and thick-walled, sheet-like substrate, whereby a charger is arranged as the primary charger in the transport direction and a secondary charger is arranged in the region after the transfer zone and both primary and secondary chargers affect the surface of the substrate to be printed.

Abstract: Toner material is transferred from a locally charged imaging member to a printed material with a d.c. voltage applied onto an a.c. voltage having voltage peaks in the range of 6-8 kV with a duration of 0.5-1.5 &mgr;sec combined with it.

Abstract: An image forming apparatus having a uniform nip between a photosensitive body and a transfer body. The image forming apparatus has a photosensitive unit on which an electrostatic latent image is formed, a developer feed unit to feed a developer onto the electrostatic latent image to form a visible image, and a transfer unit. The transfer unit has a curved side of a semi-hollow tubular shape that contacts the photosensitive unit, and a planar side opposite the curved side and secured at a support member, to transfer the visible image formed on the photosensitive unit to a recording medium. The curved side of the transfer unit has a uniform radius of curvature in an axial direction. Accordingly, the image forming apparatus can not only maintain a constant nip in relation to electrical resistance and contact pressure, but can also adjust the electrical resistance of the transfer unit by appropriately setting factors such as volume resistivity of the conductive elastic member.

Abstract: A printer includes a photosensitive member having a surface for forming a toner image and a transfer unit for transferring the toner image onto a recording paper. The transfer unit includes a transfer member arranged to face the recording paper for passing a transfer current, a discharge member arranged downstream from the transfer member in the recording paper transport direction to face the recording paper for passing a discharge current for performing discharge of the recording paper, a first guide arranged upstream from the transfer member in the recording paper transport direction for guiding the recording paper, and a second guide arranged downstream from the first guide in the recording paper transport direction for guiding the recording paper. The second guide includes a contact portion located between the transfer member and the discharge member in the recording paper transport direction for contact with the recording paper.

Abstract: A process and apparatus are provided for printing particles of a color toner that is selectively colored and can demonstrate or reflect color based upon exposure to light of known wavelength, intensity, and duration. The color toner is sensitive to a plurality of wavelengths to provide a desired color. The apparatus performs three basic functions: (1) applies the toner to a print medium, using an electrophotographic process, requiring the toner to be chargeable; (2) selectively applies light to the toner, the light being of known wavelength, intensity, and duration, to convert the toner particles to the desired color(s); and (3) bonds or attaches the toner to the print medium. Since the color toner includes all necessary colors that are selectively activated, only one color toner and thus only application of one color toner is required.

Abstract: An image transferring and recording medium conveying device for an image forming apparatus of the present invention includes a belt forming a nip for image transfer between it and an image carrier and conveying a recording medium via the nip to thereby transfer a toner image formed on the image carrier to the recording medium. A bias applying device applies a bias for image transfer to the nip. Assume that an image transfer bias Tb is applied during a leading edge interval in which the leading edge portion of the recording medium between the leading edge and a preselected position in the direction of medium conveyance moves away from the nip, and that an image transfer bias Ta is applied to the nip during a remaining interval in which the remaining portion of the recording medium moves away from the nip. Then, a controller switches the image transfer bias Tb within a range lower than the image transfer bias Ta.

Abstract: A sequential transfer-assist blade assembly includes (a) a first cam and blade assembly including a first blade segment having a first length (A1) and being movable for first contacting a first size image receiving sheet having a first center location and a first width (A2); (b) a second cam and blade assembly including a second blade segment and a third blade segment each having a second length (B1), and each being located adjacent a first end and a second end respectively of the first blade segment, the first, the second and the third blade segments being moveable for contacting a second size image receiving sheet such that the second and the third blade segments contact the second size image receiving sheet after the first blade segment, the second image receiving sheet having a center location coincident with the first center location, and having a second width (A2+2×B2); and (c) a third cam and blade assembly including a fourth blade segment and a fifth blade segment each having a third length

Abstract: A transfer device that transfers color visual images of different colors from image carriers to each of first and second sides of a recording medium. The transfer device includes a transfer element that holds and moves the recording medium, transfer bias applying devices that apply transfer biases to the recording medium by the transfer element to transfer the color visual images from the image carriers to the recording medium, respectively, and an adsorbing bias applying device that applies an adsorbing bias to the recording medium to adsorb the recording medium to the transfer element. A polarity of the adsorbing bias applied to the second side of the recording medium is opposite to that of electric charge given to the recording medium due to electric discharge generated when the recording medium is separated from the image carriers after passing through transfer nip parts formed between the image carriers and the transfer bias applying devices.

Abstract: These is provided an image forming apparatus that prevents adverse effects caused by a transferring device on image formation while no high voltages are being applied to a transferring device. The image forming apparatus includes the transferring device that transfers a developed image resting on an image carrier, to a medium, a high-voltage power supply that applies a high voltage to the transferring device, and a disabling device that disables a flow of a current through the transferring device while the high-voltage power supply is not applying any high voltage to the transferring device.

Abstract: In an electrophotographic image forming apparatus of the type including a plurality of image carriers arranged along an image transfer belt and an image transferring device configured to transfer toner images of different colors from the image carriers to a sheet being conveyed by an image transfer belt or by way of the image transfer belt by applying a bias to the belt, a bias applying method of the present invention can measure a current leaking between a plurality of high-tension power supply sections or to the ends thereof as AC resistances between respective terminals and therefore to accurately measure the leak currents of DC components. Therefore, when relatively high DC components are selected, a difference in current between a plurality of power supply sections can be maintained constant.

Abstract: Toner material is transferred from a locally charged imaging member to printed material with a d.c. voltage applied onto an imaging member and a periodic a.c. voltage combined with it.

Abstract: A pivotally movable abutment mechanism is provided, which includes an abutment member for abutting against a member to be abutted over the longitudinal direction, a supporting member that supports the abutment member and is pivotally movable about a pivotal axis, a pressing member for pivotally moving the supporting member in the direction in which the abutment member is pressed against the member to be abutted, and a pivotal axis moving mechanism capable of changing the position of the pivotal axis by a pressing operation by the pressing member.

Abstract: A transfer member having a polyimide substrate with polyaniline and two different carbon black electrically conductive fillers dispersed therein for use in electrostatographic apparatuses.

Abstract: A transfer device according to the present invention have a current detector for detecting a value of an upstream current flowing from an intermediate transfer belt into a tension roller, a transfer bias power source for performing control in such a manner as to prevent any further increase in output voltage value even if an output current value becomes lower than a value which should be subjected to a constant-current control in the case where an output signal from the current detector is a signal indicating 3.2 &mgr;A. Consequently, it is possible to suppress the unclearness of the edge of a transfer image caused by the upstream current flowing in a visible image carrying belt upstream of a transfer position such as a nip.

Abstract: In cases where equivalent air thicknesses topc (&mgr;m) and yt (&mgr;m) of the photosensitive layer and toner layer, respectively, an amount of charge per unit area (qpm (mg/cm2)−1) of the toner layer, normalized based on an amount of charge per unit area &rgr;opc in a non-image portion of the photosensitive layer, an amount of charge per unit area &rgr;′opc in the non-image portion of the photosensitive layer upon entrance into a transfer region, and a total amount of charge per unit area &rgr;o of the toner layer are set so as to satisfy the following equation, then, variance of electric field hardly occurs in the transfer region: |(&rgr;′opc−&rgr;o)/(&rgr;opc−&rgr;o)|<1 where &rgr;o=qpm{(−0.01·topc+0.145)yt2+(0.001·topc+0.937)yt}.

Abstract: An image transferring apparatus is provided which holds a print sheet in a nip between an image carrier and a transfer roller and supplies the current to the transfer roller to transfer a toner image formed on the image carrier to the print medium. The apparatus has conductive brushes disposed in contact with ends. of the transfer roller to form a bypass circuit. The bypass circuit is connected to ground through a resistor and introduce the part of the current supplied to the transfer roller in an image transferring operation, thereby avoiding formation of any print defects such as discharge-caused marks or toner stops.

Abstract: A transparent film for electrophotographic image formation thereon is formed of a transparent substrate, and a surface-coating layer disposed on at least one surface of the transparent film. The surface coating layer is characterized by exhibiting a contact angle of 55-90 deg. with pure water at 23° C. and a humidity of 50%RH; containing an electronically conductive agent as a resistivity-adjusting agent; a universal hardness of at least 150 N/mm2; and exhibiting a surface resistivity of 1×108-1×1012 ohm/□. As a result of the specified properties, the transparent film exhibits good toner image transfer characteristic and provides images free from transfer failure, such as hollow image dropout, thin image density or discharge pattern formation.

Abstract: A transfer device according to the present invention comprises a current detector for detecting a value of an upstream current flowing from an intermediate transfer belt into a tension roller, a second transfer bias power source for performing control in such a manner as to prevent any further increase in output voltage value even if an output current value becomes lower than a value which should be subjected to a constant-current control in the case where an output signal from the current detector is a signal indicating 3.2 &mgr;A. Consequently, it is possible to suppress the unclearness of the edge of a transfer image caused by the upstream current flowing in a visible image carrying belt upstream of a transfer position such as a nip.