EP0138376A2 - Verfahren und Vorrichtung zur Elektrophotographie - Google Patents

Verfahren und Vorrichtung zur Elektrophotographie Download PDF

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Publication number
EP0138376A2
EP0138376A2 EP84306194A EP84306194A EP0138376A2 EP 0138376 A2 EP0138376 A2 EP 0138376A2 EP 84306194 A EP84306194 A EP 84306194A EP 84306194 A EP84306194 A EP 84306194A EP 0138376 A2 EP0138376 A2 EP 0138376A2
Authority
EP
European Patent Office
Prior art keywords
toner
photoconductive layer
voltage
applying
photoreceptor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP84306194A
Other languages
English (en)
French (fr)
Other versions
EP0138376B1 (de
EP0138376A3 (en
Inventor
Tutomu C/O Patent Division K.K. Toshiba Saito
Hitoshi C/O Patent Division K.K. Toshiba Yoneda
Tadayoshi C/O Patent Division K.K. Toshiba Ohno
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toshiba Corp
Original Assignee
Toshiba Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP58172572A external-priority patent/JPS6064359A/ja
Priority claimed from JP58172570A external-priority patent/JPS6064364A/ja
Priority claimed from JP17257183A external-priority patent/JPS6064365A/ja
Priority claimed from JP17256983A external-priority patent/JPS6063564A/ja
Application filed by Toshiba Corp filed Critical Toshiba Corp
Publication of EP0138376A2 publication Critical patent/EP0138376A2/de
Publication of EP0138376A3 publication Critical patent/EP0138376A3/en
Application granted granted Critical
Publication of EP0138376B1 publication Critical patent/EP0138376B1/de
Expired legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/22—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20
    • G03G15/34—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 in which the powder image is formed directly on the recording material, e.g. by using a liquid toner
    • G03G15/344—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 in which the powder image is formed directly on the recording material, e.g. by using a liquid toner by selectively transferring the powder to the recording medium, e.g. by using a LED array
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/22—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20
    • G03G15/34—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 in which the powder image is formed directly on the recording material, e.g. by using a liquid toner
    • G03G15/342—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 in which the powder image is formed directly on the recording material, e.g. by using a liquid toner by forming a uniform powder layer and then removing the non-image areas
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G5/00—Recording members for original recording by exposure, e.g. to light, to heat, to electrons; Manufacture thereof; Selection of materials therefor
    • G03G5/02—Charge-receiving layers
    • G03G5/04—Photoconductive layers; Charge-generation layers or charge-transporting layers; Additives therefor; Binders therefor
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G2215/00—Apparatus for electrophotographic processes
    • G03G2215/04—Arrangements for exposing and producing an image
    • G03G2215/0497—Exposure from behind the image carrying surface
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G2217/00—Details of electrographic processes using patterns other than charge patterns
    • G03G2217/0091—Process comprising image exposure at the developing area

Definitions

  • the present invention relates to a method and apparatus of electrophotography utilized for a printer or a copying machine and, more particularly, to a method and apparatus for forming a toner image utilizing a photoreceptor having a photoconductive layer and a toner having no photoconductivity.
  • Electrophotography generally refers to an image-forming technique combining the photoconductive effect and the electrostatic attraction phenomenon.
  • a development step is required in which an electrostatic latent image is formed on a photoreceptor and is converted into a toner image. This has prevented production of a more compact and inexpensive image-forming apparatus.
  • the development step of an electrostatic latent image leads to a degradation in the picture quality due to the edge effect in which the field strength differs between the central and peripheral portions of the electrostatic latent image.
  • the effective sensitivity of the photoconductive toner is considerably lower than that of a photoreceptor used in other electrophotography techniques. This may be attributed to the following. First, during exposure, the light does not reach in a sufficient amount the deep region of the toner layer (i.e., the region near the support of the tonner layer). Second, since the contact resistance between the toner particles is great, the charge generated upon exposure has difficultly reaching the support. If the sensitivity of the photoconductive toner is low, the density of the toner image is lowered, and fog occurs around the toner image, thus degrading picture quality. A photoconductive toner having a high sensitivity has not been proposed.
  • a method of electrophotography wherein a toner having no photoconductivity is applied on a surface of a photoconductive layer of a photoreceptor obtained by stacking a transparent electrically conductive layer and the photoconductive layer on a transparent substrate; and wherein the photoconductive layer is exposed from the side of the transparent substrate to transfer the toner from an exposed region of the photoconductive layer to the toner-receiving paper opposite the photoconductive layer, thereby forming a toner image.
  • the toner is removed from the exposed region of the photoconductive layer, and the toner is transferred from a non-exposed region of the photoconductive layer to toner-receiving paper to obtain a toner image in the same manner.
  • a latent image-forming process is omitted, thereby eliminating image degradation such as the generation of a ghost caused by an edge effect occurring when the latent image is developed.
  • the photoconductive layer is uniformly charged to one polarity.
  • the toner has an insulating characteristic and is applied to the surface of the photoconductive layer after the toner is charged to a polarity opposite that of the photoconductive layer.
  • the attractive force of the toner on the exposed region of the photoconductive layer is weakened, so that this toner can easily be transferred from the surface of the photoconductive layer to the toner-receiving paper by utilizing an electrostatic attractive force, or so that the toner can be easily removed from the surface of the photoconductive layer.
  • the toner has a given conductivity, and toner particles on the exposed region of the photoconductive layer are selectively charged.
  • the toner on the exposed region of the photoconductive layer is charged.
  • the toner can be easily transferred from the surface of the photoconductive layer to the toner-receiving paper or can be removed from the surface of the photoconductive layer by utilizing the electrostatic attractive force.
  • the toner does not have photoconductivity. Fog caused by use of photoconductivity toner does not occur in the toner image, thereby preventing the ghost caused by the edge effect and hence obtaining a high-quality image.
  • a transparent electrically conductive layer and a photoconductive layer are stacked on a transparent substrate to constitute a photoreceptor which is moved along a predetermined direction, and a means for performing the above processes is arranged along the direction of movement of the photoreceptor.
  • a means for transferring toner on an exposed region of the photoconductive layer to toner-receiving paper comprises an opposite electrode which is formed opposite the photoconductive layer and to which a voltage of one polarity is applied.
  • the exposing means and the transferring means or toner-removing means are arranged to be opposite to each other with the photoreceptor interposed therebetween.
  • the space factor is improved, and the apparatus can be simplified and rendered compact in size. Furthermore, since the exposing means is separated from the toner layer, the charged toner scattered on the photoconductive layer will not be attached to the exposing means to impair the exposure state, thereby reducing the frequency of maintenance.
  • the electrophotography apparatus also preferably has a means for removing the residual toner which is not transferred onto the toner-receiving paper and remaining on the photoconductive layer, and means for conveying the removed toner to a toner-applying means, thereby allowing efficient use of a toner.
  • the photoreceptor 10 used in the present invention has the structure shown in Fig. 1 wherein a transparent electrically conductive layer 12 and a photoconductive layer 13 are sequentially formed on a transparent substrate 11.
  • the transparent substrate 11 can be a glass plate or an organic material sheet.
  • the transparent conductive layer 12 can comprise a NESA glass film, an indium oxide (In 2 0 3 ) film, or the like.
  • the photoconductive layer 13 can consist of amorphous-Se, ZnO, OPC, amorphous-Si, CdS or the like.
  • transparent herein means optical transparency such that light of a specific wavelength used in exposure is transmitted, and does not therefore necessarily mean colorless transparency.
  • the photoconductive layer 13 has a suitable spectral sensitivity for the wavelength of light used for exposure.
  • the thickness of the photoconductive layer 13 is preferably smaller than that of a photoconductive layer which is used in a photoreceptor of a conventional electrophotography apparatus.
  • the photoconductive layer 13 consists of amorphous-Se, for example, it preferably has a thickness of about 1 to 20 ⁇ m as compared to a thickness of 50 to 60 ⁇ m of the photoconductive layer of the conventional apparatus. This is attributed to the following.
  • the photoconductive layer 1 3 When the photoconductive layer 1 3 is exposed with light received through the transparent substrate 11, the light must be able to reach near the surface of the photoconductive layer 13 on which the toner is attached.
  • Figs. 2A to 2D Image forming processes according to a first embodiment of a method of electrophotography of the present invention will be described with reference to Figs. 2A to 2D.
  • the photoconductive layer 13 of the photoreceptor 10 shown in Fig. 1 is uniformly charged to a given polarity (positive in the drawings) by a charger 21 in a dark-environment.
  • toner 22 charged to the opposite polarity (negative) of that of the photoconductive layer 13 is applied on the entire surface of the photoconductive layer 13.
  • the toner 22 is an insulating toner generally used in conventional electrophotography and does not have photoconductivity.
  • the toner 22 can be applied by various methods such as the method of applying a charged toner with a blade, the magnetic brush method combining a powder consisting of a magnetic carrier and toner with a magnetic roller, the cascade method using a powder consisting of a toner and a relatively coarse bead-like substance, the fur brush method using a toner and a fur brush, and the powder cloud method of spraying a toner through a metal pipe and atomizing it.
  • the toner on the exposed region of the photoconductive layer 13 is removed from the surface of the photoconductive layer 13 by an electric field which is generated between the transparent conductive layer 12 and the opposite electrode 24 upon application of a voltage from the power source 25.
  • the toner is moved toward the opposite electrode 24 and is transferred onto the surface of toner-receiving paper 26 held between the photoconductive layer 13 and the opposite electrode 24.
  • the toner-receiving paper 26 can be plain paper.
  • the voltage from the power source 25 is preferably a pulsating voltage obtained by superposing an AC voltage on a DC voltage.
  • the timing of the voltage applied between the transparent conductive layer 12 and the opposite electrode 24 from the power source 25 need not be synchronous with the timing of the exposure but may be applied after exposure.
  • the residual toner on the nonexposed region of the photoconductive layer 13 is removed by a cleaning blade 27 and is reused.
  • the cleaning method may alternatively be a fur brush cleaning method or the like.
  • FIG. 3 shows an LED printer according to an embodiment of an apparatus of electrophotography utilizing the image-forming processes described above.
  • a photosensitive drum (photoreceptor) 30 is formed in a cylindrical shape such that its photoconductive layer faces outward.
  • a transparent conductive layer of this photosensitive drum 30 comprises, for example, a deposition film of In 2 0 3 , and the photoconductive layer thereof comprises, for example, a selenium film having a thickness of 15 ⁇ m.
  • the photosensitive drum 30 is driven to rotate in the direction indicated by arrow 31.
  • a charger 32, a toner applying means 33, an exposing means 36, an opposite electrode 37, and a cleaning station 41 are arranged along the rotating direction of the photosensitive drum 30 as a means which is used in the processes shown in Figs. 2A to 2D.
  • the charger 32 charges the photoconductive layer of the photosensitive drum 30 to have a surface potential of about + 200 V.
  • the toner applying means 33 applies on the surface of the charged photoconductive layer by means of a blade 35 a toner negatively charged by being stirred by a charging roller 34.
  • the exposing means 36 arranged inside the photosensitive drum 30 comprises an LED (light-emitting diode) array arranged linearly along the direction of the rotating axis of the drum 30, and a rod lens array for guiding light from the LED array.
  • the exposing means 36 exposes the photoconductive layer from the transparent substrate side of the drum 30.
  • the LED array is driven in accordance with an electrical image signal supplied from an external drive circuit.
  • the exposing means 36 is adjusted such that the photoconductive layer is located within the focal depth of the rod lens array.
  • the opposite electrode 37 is located opposite the exposing means 36 with the photosensitive drum 30 interposed therebetween.
  • the opposite electrode 37 comprises an aluminum roller having a diameter of 5 mm and a conductive rubber sheet wound therearound and having a resistivity (or specific resistance) of 1,000 2-cm.
  • the opposite electrode 37 is pressed by a spring 38 toward the photosensitive drum 30 through toner-receiving paper 39 at a force of 0.7 kg/cm 2 .
  • a positive voltage for example, about +180 V is applied to the opposite electrode 37.
  • This voltage is preferably a voltage obtained by superposing an AC voltage on a DC voltage.
  • the toner on the exposed region of the photoconductive layer whose attractive force is weakened upon exposure to the exposing means 36 is transferred to the toner-receiving paper 39.
  • a toner image corresponding to the electrical image signal supplied to the exposing means 36 is formed on the toner-receiving paper 39.
  • the toner image is fixed on the toner-receiving paper by a fixing station 40 to be an output image.
  • the toner image thus obtained has a uniform density at a solid portion and clear printing elements in a line drawing portion. Thus, an excellent image can be obtained for various types of image patterns.
  • the residual toner on the photosensitive drum 30 which was not used in image formation is removed by a rotating fur brush at the cleaning station 41.
  • a charge removal lamp 43 for radiating light onto the lower surface of the drum 30 is arranged in the cleaning station 41.
  • the toner removed by the cleaning station 41 is guided to a conveying means 44 to be conveyed to the toner applying means 33 through a chain 45 for reuse.
  • FIG. 4 shows an embodiment wherein the image-forming processes shown in Figs. 2A to 2D are applied to a laser printer.
  • a web shape photoreceptor is used.
  • the use of such a photoreceptor provides less limitations on the size of the exposure means or on the length of the optical path from the exposure means to the photoreceptor.
  • a photosensitive web 50 comprises a polyethylene terephthalate film having a thickness of about 50 ⁇ m as a transparent substrate, a palladium film deposited thereon as a transparent conductive layer, and an Se-As-Te photosensitive material layer having a thickness of about 15 ⁇ m as a photoconductive layer.
  • the web 50 is moved from a supply roller 51 to a take-up roller 55 at a suitable speed.
  • a charger 32, a toner-applying means 56, an exposing means 58, an opposite electrode 59, and a cleaning station 41 are arranged along the moving direction of the photosensitive web 50.
  • the photoconductive layer of the photosensitive web 50 is charged by the charger 32 to have a surface potential of about + 2 00 V. Then, toner is uniformly applied on the photoconductive layer with the toner-applying means 56.
  • the toner-applying means 56 adopts in this embodiment the magnetic brush method which combines a mixture of a magnetic carrier and toner, and a magnetic roller 57.
  • the means 56 applies the negatively charged toner by friction with the carrier on the photoconductive layer.
  • the amount of toner applied can be controlled by changing the voltage applied from a control power source (not shown) to the magnetic roller 57 within a range of, for example, +50 V to +100 V. Thus, the density of the output image can be changed as needed.
  • the exposing means 58 exposes the photoconductive layer applied with the toner from the side of the transparent substrate.
  • the exposing means 58 comprises an optical system mainly having a laser diode, a polygon mirror, a scanning lens, and a peripheral circuit including a drive circuit.
  • the exposing means 58 is adjusted such that the photoconductive layer is located within the focal depth of the optical system.
  • the laser beam is modulated in accordance with an electrical modulation signal supplied from an external circuit and linearly scans the photoconductive layer of the web 50 using the polygon mirror and the scanning lens from the side of the transparent substrate along the perpendicular direction toward the sheet of the drawing.
  • the toner with the weakened attractive force toward the photoconductive layer upon exposure is transferred onto toner-receiving paper 39 by the electric field generated by the voltage applied to the opposite electrode 59 during exposure.
  • a toner image is thus formed.
  • the opposite electrode 59 comprises a corona charger in this embodiment.
  • the distance from the web 50 to a corona wire of the corona charger is set to be 15 mm, and a voltage applied to the corona wire is set to be +5.5 kV.
  • the toner image is fixed by a fixing station 40, as in the case of the embodiment shown in Fig. 3.
  • the toner remaining on the web 50 is removed by a cleaning station 41, and the removed toner is conveyed to a toner-applying means 56 by a toner conveying means 44.
  • Figs. 5A to 5D show image-forming processes according to a second embodiment of a method of electrophotography of the present invention.
  • the processes shown in Figs. 5A and 5B are the same as those shown in Figs. 2A and 2B.
  • Fig. 5C After the process of Fig. 5B, as shown in Fig. 5C, light 23 corresponding to an input image is irradiated onto a photoconductive layer 13 through a transparent conductive layer 12 from the side of a transparent substrate 11, thereby performing exposure.
  • toner in an exposed region of the photoconductive layer 13 looses some of its attractive force. Utilizing this phenomenon, simultaneously or after the exposure, the toner on this exposed region is removed by a blower 29.
  • toner remains on the non-exposed region of the photoconductive layer 13.
  • the toner may be removed by other methods such as by using a conductive roller, by combining a conductive roller and a dielectric roller, by using a dielectric film and a corona charger for charging this film, or by other methods.
  • a voltage having the opposite polarity as that of the toner is applied from a power source 25 to an opposite electrode 24 arranged opposite the photoconductive layer 13. Then, the toner remaining on the non-exposed region of the photoconductive layer 13 is removed from the layer 13 and is transferred to toner-receiving paper 26 held between the photoconductive layer 13 and the opposite electrode 24.
  • the photoconductive layer 13 is preferably irradiated with light from a lamp 28 from the side of the transparent substrate 11 through the transparent conductive layer 12. Upon this irradiation with light, the attractive force of toner toward the photoconductive layer 13 is effectively weakened, and the transfer efficiency of the toner image is improved by about 100%. Therefore, the cleaning process after the transfer process can be omitted.
  • FIG. 6 shows an LED printer as an embodiment of an apparatus of electrophotography utilizing the image-forming processes shown in Figs. 5A to 5D.
  • a toner-removing means 60 is arranged at a position to be opposite to an exposing means 36 with a photosensitive drum 30 interposed therebetween.
  • the toner-removing means 60 comprises a conductive roller 61 similar to that used in the opposite electrode 37 shown in Fig. 3, a spring 62 for pressing the roller 61 toward the drum 30 through the toner-receiving paper 39, and a blade 63.
  • a voltage having a polarity opposite that of the toner, for example, +1 2 0 V, is applied to the roller 61.
  • a transferring means 64 comprises an opposite electrode 65 and a lamp 66.
  • the opposite electrode 65 is a corona charger.
  • the distance from the drum 30 to the corona wire of the corona charger is set to be 15 mm, and the application voltage on the corona wire is set to be + 5 . 5 kV.
  • Fig. 7 shows an embodiment wherein the image-forming processes shown in Figs. 5A to 5D are applied to a copying machine.
  • a photosensitive web 50 and a moving means therefor are of the same construction as that shown in Fig. 4, and the remaining structure is the same as that shown in Fig. 6 except an exposing means.
  • An exposing means 70 is an optical system comprising a document table 71 for placing a document (orignal object) 72 thereon, a light source 73 for illuminating the surface of the document 72 through the document table 71, and a lens 74 for forming an image of the document 72 onto the photoconductive layer of the photosensitive web 50.
  • the document table 71 is moved together with the web 50, so that the image on the entire surface of the document 72 is scanned and formed on the photoconductive layer of the web 50.
  • Figs. 8A to 8C show image-forming processes according to a third embodiment of a method of electrophotography of the present invention.
  • toner 81 is applied on the entire surface of a photoconductive layer 13 of a photoreceptor 10.
  • the toner 81 has an electrical conductivity and preferably has a resistivity of 10 6 to 10 8 n.cm.
  • the method of applying the toner can be the same as in the earlier embodiments.
  • the photoconductive layer 13 need not be charged.
  • a voltage of a single polarity is applied from a power source 84 to an opposite electrode 83 opposite the photoconductive layer 13.
  • the voltage is negative in this embodiment but can be positive.
  • the power source 84 also preferably generates a pulsating voltage.
  • An exposed region of the photoconductive layer 13 is rendered conductive and is injected with positive charges.
  • the toner on the exposed region of the photoconductive layer 13 is removed from the surface of the photoconductive layer 13 by an electric field generated between the transparent conductive layer 12 and the opposite electrode 83 from the power source 84.
  • the toner is transferred onto the surface of toner-receiving paper 85 held between the photoconductive layer 13 and the opposite electrode 83. A toner image is thus formed.
  • the toner which was not used in forming the image remaining on the photoconductive layer 1 3 is removed by a cleaning blade 86 and reused.
  • the removing method may be one of the methods described above.
  • the removed toner is conveyed to be used for another toner application process, as shown in Fig. 8A.
  • the image can be formed with less processes than is shown in Figs. 2A to 2D or in Figs. 5A to 5D.
  • Fig. 9 shows an embodiment wherein the image-forming processes shown in Figs. 8A to 8C are applied to an LED printer.
  • a blade 35 is formed of a conductive rubber, and a voltage is applied to the blade 35 from a power source 91.
  • the toner applied on the photoconductive layer of a photosensitive drum 30 is injected with charges and is thus rendered with an electrostatic attractive force acting in addition to the mechanical attractive force toward the photoconductive layer. Therefore, in the printer as shown in Fig. 9 wherein the toner is subject to the influence of gravity between the toner application process, and the exposure and transfer processes, the inadvertent removal of the toner from the photosensitive drum 30 is prevented. Stable toner application and conveying can therefore be performed.
  • the polarity of the charge injected in the toner in this toner application process is preferably opposite to that of the charges injected in the exposure and transfer processes.
  • a transferring means 92 comprises a power source 94 and an opposite electrode 93 which is opposite the exposure means 36 comprising LEDs with the drum 30 interposed therebetween.
  • the opposite electrode 93 is an electrically conductive roller as described above and is applied with a voltage of a single polarity, for example, about -600 V from the power source 94, preferably a pulsating voltage.
  • the exposure by the exposing means 36 is performed simultaneously with the transfer of the toner image onto the toner-receiving paper 39.
  • the toner remaining on the drum 30 is removed by a cleaning station 95, and is conveyed to the toner-applying means 33 by a toner-conveying means 44.
  • the cleaning station 95 is omitted.
  • the cleaning station 95 can be omitted for the following reason. Since the toner has an electrical conductivity, the attractive force of the toner remaining on the photosensitive drum 30 is extremely weak, and the toner can be formed into a uniform thin film by the toner applying means 33.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Electrophotography Using Other Than Carlson'S Method (AREA)
EP19840306194 1983-09-19 1984-09-11 Verfahren und Vorrichtung zur Elektrophotographie Expired EP0138376B1 (de)

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
JP172569/83 1983-09-19
JP172572/83 1983-09-19
JP58172572A JPS6064359A (ja) 1983-09-19 1983-09-19 画像形成方法および装置
JP172571/83 1983-09-19
JP58172570A JPS6064364A (ja) 1983-09-19 1983-09-19 画像形成方法および装置
JP17257183A JPS6064365A (ja) 1983-09-19 1983-09-19 画像形成方法および装置
JP17256983A JPS6063564A (ja) 1983-09-19 1983-09-19 画像形成方法および装置
JP172570/83 1983-09-19

Publications (3)

Publication Number Publication Date
EP0138376A2 true EP0138376A2 (de) 1985-04-24
EP0138376A3 EP0138376A3 (en) 1985-07-17
EP0138376B1 EP0138376B1 (de) 1987-03-04

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EP19840306194 Expired EP0138376B1 (de) 1983-09-19 1984-09-11 Verfahren und Vorrichtung zur Elektrophotographie

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EP (1) EP0138376B1 (de)
DE (1) DE3462558D1 (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3615387A1 (de) * 1985-05-10 1986-11-13 Seikosha Co., Ltd., Tokio/Tokyo Elektrofotografisches verfahren
DE10235591A1 (de) * 2002-08-03 2004-02-19 Koenig & Bauer Ag Verfahren und Vorrichtung zum Herstellen einer Druckform für eine Rotationsdruckmaschine

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2924519A (en) * 1957-12-27 1960-02-09 Ibm Machine and method for reproducing images with photoconductive ink
GB876577A (en) * 1957-12-10 1961-09-06 Otto Kurt Kolb Method and apparatus for producing a developed xerographic print simultaneously with exposure
GB1463890A (en) * 1973-12-20 1977-02-09 Ibm Xerographic printing machine

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB876577A (en) * 1957-12-10 1961-09-06 Otto Kurt Kolb Method and apparatus for producing a developed xerographic print simultaneously with exposure
US2924519A (en) * 1957-12-27 1960-02-09 Ibm Machine and method for reproducing images with photoconductive ink
GB1463890A (en) * 1973-12-20 1977-02-09 Ibm Xerographic printing machine

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3615387A1 (de) * 1985-05-10 1986-11-13 Seikosha Co., Ltd., Tokio/Tokyo Elektrofotografisches verfahren
FR2581772A1 (fr) * 1985-05-10 1986-11-14 Seikosha Kk Procede d'electrocopie
GB2176025A (en) * 1985-05-10 1986-12-10 Seikosha Kk Electrophotographic process
DE10235591A1 (de) * 2002-08-03 2004-02-19 Koenig & Bauer Ag Verfahren und Vorrichtung zum Herstellen einer Druckform für eine Rotationsdruckmaschine
DE10235591B4 (de) * 2002-08-03 2005-03-03 Koenig & Bauer Ag Vorrichtung zum Bebildern der Oberfläche eines Druckformzylinders oder einer auf dem Druckformzylinder aufgespannten Druckform

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Publication number Publication date
EP0138376B1 (de) 1987-03-04
EP0138376A3 (en) 1985-07-17
DE3462558D1 (en) 1987-04-09

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