EP0092107B1 - Procédé de tirage électrophotographique et dispositif pour ôter le liquide de développement d'une surface photoconductrice - Google Patents

Procédé de tirage électrophotographique et dispositif pour ôter le liquide de développement d'une surface photoconductrice Download PDF

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Publication number
EP0092107B1
EP0092107B1 EP83103347A EP83103347A EP0092107B1 EP 0092107 B1 EP0092107 B1 EP 0092107B1 EP 83103347 A EP83103347 A EP 83103347A EP 83103347 A EP83103347 A EP 83103347A EP 0092107 B1 EP0092107 B1 EP 0092107B1
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EP
European Patent Office
Prior art keywords
photoconductor
voltage
roller
charged
developer liquid
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Expired
Application number
EP83103347A
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German (de)
English (en)
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EP0092107A1 (fr
Inventor
Roland Dr. Moraw
Günther Schädlich
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Hoechst AG
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Hoechst AG
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    • 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
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/10—Apparatus for electrographic processes using a charge pattern for developing using a liquid developer
    • G03G15/11—Removing excess liquid developer, e.g. by heat

Definitions

  • the invention relates to an electrophotographic copying process with removal of the developer liquid from a photoconductor surface, in which a photoconductor layer is electrostatically charged and informationally exposed, the latent charge image obtained on the photoconductor layer being developed with a developer liquid to form a visible toner image, excess developer liquid with one on the photoconductor adjacent element is removed, the toner image is electrophoretically transferred from the photoconductor to an image receiving material and fixed thereon, and the photoconductor is cleaned and / or discharged, and a device for carrying out the method.
  • DE-A-3 018 241 discloses such a method for removing excess developer liquid of a liquid developer consisting of an insulating developer liquid and charged toner particles suspended therein from a photoconductive surface which bears an electrostatic charge image developed by means of the liquid developer.
  • a drying element in the form of a squeeze roller or a suction roller is brought into contact with the photoconductive surface, the squeeze roller or the suction roller being kept at a potential whose polarity is equal to the polarity of the charge of the charged toner particles and moreover the relative movement between the photoconductive surface and the squeeze roller or the suction roller is controlled so that the relative speed in the contact area becomes zero.
  • the outer surface of the squeeze roller or the suction roller consists of an elastomeric material which has a Shore A hardness of less than 45 and a resistance value of less than 10 9 Ohm.cm.
  • the photoconductive surface is on a drum which runs counterclockwise past a metering or stripper roller which is suitable for limiting the amount of liquid remaining on the photoconductor after the latent charge image has developed. This metering or stripping roller does not touch the developed charge pattern, so that neither streaks nor distortions are generated. A developer liquid layer with a thickness of between 10 and 15 ⁇ m then remains on the surface of the photoconductor.
  • the drum surface After passing the metering or scraper roller, the drum surface passes the squeeze roller, which is held at such a pretension that an electric field results, by which the toner is held on the photoconductor surface.
  • the bias applied to the nip roller has the same polarity as the toner particles in the developer liquid. In this way, it is achieved that the developed image adheres to the surface of the photoconductor without streaking, without smearing and without the toner being transferred to the nip roller.
  • the liquid developer layer still present on the photoconductor surface is reduced to a thickness of 2 to 3 ⁇ m after passing the squeeze roller, so that the layer thickness of the developer liquid on the photoconductor is reduced overall to about a fifth of the initial value.
  • the information on the copy quality is limited to the fact that there are no drag marks, stripes and distortions in the copy. No information is given about the achievable copy density, which is an important criterion especially in the case of the squeeze roller technology, since a part of the toner particles deposited electrophoretically on the photoconductor is also squeezed off by the squeeze roller. Even if coarse stripes are avoided on the copies, even very short stripes on the edges caused by the squeezing affect the edge sharpness perpendicular to the running direction and thus the achievable resolution.
  • the resolution must be about six lines / mm both in the direction of travel as well as transversely to it, in order to be able to produce legible copies of the first and second generation from the previous copies.
  • the liquid development has the disadvantage that residual developer liquid, in particular, is removed by the copies after the transfer of the toner image from the photoconductor surface to the image-receiving material and when fixing the Copies must be evaporated by heating.
  • developer liquid is lost in large quantities and must be replenished again and again in the copying machine, and on the other hand, the air in the vicinity of the copying machine undesirably accumulates with evaporated developer liquid.
  • the usual developer liquids as such are not toxic, these are predominantly aliphatic hydrocarbons such as i-decane, in which the charged toner particles are dispersed, the large discharge of developer liquid is also undesirable for reasons of low environmental impact.
  • developer liquid thus reduces the layer thickness of the developer liquid by means of a stripping roller rotating in the opposite direction to the photoconductor before the transfer of the toner image to the image-receiving material.
  • a scraper roller rotates in opposite directions at a high peripheral speed the photoconductor layer. The one on the deposited toner images are not blurred, but the excess amount of developer liquid is only partially removed so that wet copies are ejected.
  • the object of the invention is to improve a method and a device of the generic type in such a way that good resolution and high copy density are obtained with the copies largely reducing the discharge of developer liquid.
  • the device for carrying out the method is characterized in that the charging device consists of a direct current corona and a high-voltage supply circuit which is designed for a continuous operating voltage of 8 kV, that the element for removing developer liquid is present under pressure on the peripheral surface of the photoconductor drum, and above a gear drive with a gear on the shaft of a photoconductor drum is engaged such that the peripheral speed of the element is 2% to 20% greater than the peripheral speed of the photoconductor drum, which is driven in the same direction as the element in the common contact area, and that the transfer station is a direct current corona with an operating voltage of up to 8 kV.
  • the advantages are achieved that with relatively easy to implement measures, such as a higher charge of the photoconductor surface, compared to the photoconductor surface faster rotating nip roller to remove the excess developer liquid and transfer of the developed toner image from the photoconductor surface to the image receiving material with a higher transfer voltage, whereby each of these three measures is opposite to the conventional measures, the discharge of developer liquid can be halved compared to the prior art, without sacrificing the required copy quality.
  • measures such as a higher charge of the photoconductor surface
  • a photoconductor layer is generally charged and exposed, the charge images are developed with charged toner particles dispersed in the developer liquid, excess developer liquid is removed from the photoconductor layer by rollers, and the toner images are transferred to image-receiving material, such as paper sheets.
  • the photoconductor layer is then cleaned for the next copying cycle and, if necessary, discharged.
  • the photoconductors are either applied in the form of tapes to supports which consist, for example, of polyester films with a conductive layer of vapor-deposited aluminum or are vapor-deposited on the outer surfaces of metallic drums.
  • the flexible tapes are mostly coated with elastic organic photoconductor layers made of poly-N-vinylcarbazole and trinitrofluorenone.
  • the copiers are equipped with conductive aluminum drums on which the photoconductor layer is vapor-deposited.
  • inorganic photoconductors such as selenium or alloys of selenium with tellurium or arsenic are used in particular on the drums.
  • the invention is described primarily with reference to photoconductor layers made of selenium or alloys of selenium with tellurium or arsenic, but this does not represent any restriction of the inventive concept, which is also valid for organic photoconductors.
  • FIG. 1 The structure of a copying machine with which the method according to the invention can be carried out corresponds to the prior art and is shown schematically in FIG. 1.
  • a drum 1 is provided with a photoconductor 21 and is rotated counterclockwise by a drive source, not shown, at a predetermined speed.
  • a drive source not shown
  • the photoconductor 21 is made of organic material, for example poly-N-vinylcarbazole / trinitrofluorenone, the photoconductor is negatively charged by the electrostatic charging device, while a positive charge takes place in the case of a photoconductor 21 made of selenium.
  • the charged photoconductor 21 is exposed for information in the exposure station 3 via its optics, i.e. exposed with a radiation pattern of an original.
  • the electrostatic latent charge image obtained is made visible in the development station 22 by means of the developer liquid; developed oner picture.
  • the development station 22 consists of a curved plate 4, which is adapted with its curvature to the peripheral surface of the drum 1 and a trough 5, which is filled with developer liquid.
  • the plate 4 serves as a development electrode and is supplied with a certain voltage by a voltage source, not shown.
  • a roller can also be provided.
  • the toner particles dispersed in the developer liquid are positively charged, while in selenium layers they are negatively charged. Excess developer liquid is largely removed by the removal device, which consists of the roller 6 with a scraper 7.
  • image-receiving material for example a paper sheet 8 is fed to the drum 1 from a container 25.
  • the transfer station 16 contains a charging device 9, for example a corona, which charges the paper sheet 8 electrostatically from the rear. In the case of a selenium photoconductor 21, the paper sheet 8 is charged positively.
  • a pressure roller can also be provided, which bears against the peripheral surface of the drum 1 and is connected to a voltage source which charges the pressure roller to a suitable potential for the transfer. After the transfer of the toner image from the photoconductor 21 to the paper sheet 8, the latter is detached from the peripheral surface of the drum 1 and passed over a heating device 10 which dries the still moist toner image.
  • the cleaning device comprises a roller 11, for example a foam roller, and a wiper lip 12 which is arranged in the immediate vicinity of the roller 11.
  • the roller 11 is wetted with developer liquid and, together with the wiper lip 12, cleans the toner surface of the photoconductor surface.
  • the charging device 13 removes all residual charges of the photoconductor 21, which is completely discharged.
  • the DC corona 2 is supplied with an operating voltage of +6.5 kV when the photoconductor 21 is selenium.
  • the approximately 50 gm thick selenium photoconductor layer which is charged to a maximum of + 1150 V, is discharged and then corresponding to that on the Residual charge present in the photoconductor layer is deposited to develop the latent charge image into a toner image.
  • the charging device 14 consists of the DC corona 2, which is connected to a high-voltage circuit 15, which is designed for a continuous operating voltage of 8 kV of the DC corona 2.
  • the element for removing the developer liquid from the surface of the photoconductor 21 is preferably a squeeze roller 6 which rotates at a peripheral speed which is 2 to 20% higher than the rotational speed of the drum 1.
  • the squeeze roller is in line contact with the photoconductor 21 and is applied to the photoconductor surface by a linear lever 23 and a tension spring 24, which acts on one end of the angular lever, with a linear pressure equal to or greater than 0.5 N / cm Drum 1 pressed.
  • the angular lever 23 is articulated on the axis of the squeeze roller 6 at one end and can be pivoted about a pivot point.
  • the line pressure between the squeeze roller 6 and the photoconductor surface of the drum 1 can also be 1 to 3 N / cm.
  • An elastic wiper blade 7 rests on the squeeze roller 6 and wipes off any developer liquid that protrudes from its peripheral surface.
  • the squeeze roller 6 is longer than the photoconductor drum 1 and protrudes beyond the end faces of the photoconductor drum 1. It is also possible, although this is not shown, for the squeeze roller to project beyond the end face of the photoconductor drum on only one side.
  • the squeeze roller 6 consists of a metal core and an elastic sleeve 20 with a thickness of 4 to 8 mm.
  • the Shore A hardness of the casing material is 25 to 60.
  • the material of the casing 20 is polyurethane with an addition of iron oxide and has a Shore A hardness of 27. It is essential that the surface of the casing 20 is smooth and has only bumps up to a maximum of 2 p.m., but bumps smaller than 1 ⁇ m are preferred. Such a smooth surface of the shell 20 is achieved primarily by casting.
  • two angular levers 23, one each on the end face of the nip roller 6, are provided, which are pivotably mounted.
  • the squeeze roller 6 is in engagement via a gear drive 17 with a gear 18, which is seated on the shaft 19 of the drum 1.
  • the gear ratio between the gear drive 17 and the gear 18 is selected such that the peripheral speed of the nip roller 6 is about 2 to 20% greater than the peripheral speed of the drum 1 and that the nip roller 6 and the drum 1 are driven in the same direction in the contact area.
  • FIG. 3a shows the voltage in volts of a selenium photoconductor as a function of the light energy LE incident on the photoconductor, which is given in relative units.
  • the specific charge i.e. the voltage per unit length of the photoconductor layer thickness is 23 V / ⁇ m.
  • the voltage decreases exponentially with the incident light energy, i.e. the greater the incident light energy, the more the photoconductor layer is discharged.
  • FIG. 3b the toner densities corresponding to the voltage values from FIG. 3a are plotted on the printed copies as a function of the incident light energy LE, which in turn is shown in relative units.
  • the toner density D is determined by the logarithm. of the ratio of incident light quantity and the light quantity reflected from the developed toner image on the copy.
  • a maximum density of 1 is already obtained at a voltage of + 850 V, with a compensated residual voltage of + 150 V.
  • lower density toner images are developed.
  • this charge is, for example, + 1150 V.
  • the charge point of the maximum toner density U maxD is the charge voltage of the photoconductor, which results in copies with a maximum density equal to 1 without discharge by exposure under the respective operating conditions .
  • FIG. 4a and 4b show the voltage values during the exposure of a photoconductor layer charged with +8 kV and the corresponding copy densities as a function of the incident light energy LE, again measured in relative units.
  • the copy density decreases again when charging above the charging point of maximum toner density UmaxD.
  • This reduced toner density of the copies can be compensated for by a larger transmission voltage in the transmission station 16 according to FIG. 1.
  • the voltage at the DC corona 9 in the transfer station 16 is increased from the usual +6.3 to +6.5 kV to +7.5 kV in the copying machine according to FIG. 1. If the transfer station works with a transfer roller instead of a transfer corona, its potential must be increased accordingly.
  • the toner images on the photoconductor layers are no longer adversely affected by the squeeze roller 6 above charge voltages of approximately 1300 V, ie from specific voltages of 26 V / ⁇ m.
  • the charge on the photoconductor layers must not be so high that breakdowns occur in the photoconductor layers.
  • photoconductor layers with a thickness of 50gm selenium up to approx. + 1800 V, that is 36 V / li m can be charged without breakdowns.
  • Photoconductor layers made of a selenium alloy with tellurium and a thickness of 65 1 im can be charged up to about +2500 V, that is 38 V / li m.
  • the squeeze roller 6 is equipped with an elastic sleeve made of a solvent-resistant material, such as polyurethane, as already mentioned, the sleeve being seated on a metal core of the roller.
  • the shell material is elastic and has a Shore A hardness of 25 to 60, in particular less than 35. For a low discharge of developer liquid, it proves advantageous to choose the thickness of the shell in the range from 4 to 8 mm. A Shore A hardness of less than 30, for example 27, is provided for thicknesses of more than 8 mm of the casing.
  • the conductivity of the nip roller 6 has no noticeable influence on the copy quality.
  • no potential of a certain size is applied to the squeeze roller 6, rather the metal core of the squeeze roller 6 is generally grounded.
  • the wiper blade 7 made of plastic or metal, which lies flat on the surface of the squeeze roller 6, is used for cleaning the squeeze roller 6.
  • Essential for an effective reduction in the amount of developer liquid discharged is a uniformly strong pressure of the squeeze roller 6 over the entire width of the photoconductor surface of the drum 1.
  • the squeeze roller 6 In the method according to the invention, it is necessary to make the surface of the squeeze roller 6 as smooth as possible. Surface structures of a few micrometers in height increase the amount of developer liquid discharged considerably. For example, in the case of structures of 5/7/9, the amounts of developer liquids discharged by the copies behave as high as 1: 1.3: 1.8. Therefore, the squeeze rollers used have surfaces with structures less than 2 ⁇ m in height or less than 1 ⁇ m in height. In order to produce such smooth rolls from elastic material, it is necessary to cast them in polished molds or to produce the squeeze rolls by surface calendering at elevated temperature. By turning, grinding and polishing, smooth roller surfaces made of elastic material are very labor intensive and difficult to manufacture.
  • the squeeze roller 6 projects beyond the two end faces or at least over one end face of the drum 1 in order to have moist, black edges on the edges of the copies avoid. If the squeeze roller 6 closes flush with the photoconductor 21, ah the squeeze roller 6 and the drum 1 are of the same width, moist black edges appear on the edges of the copies in the running direction. Only when a squeeze roller 6 is used, which is a few millimeters wider than the drum 1, do the edges remain dry and clean. For a practical application, a lateral protrusion of the squeeze roller 6 of 2 to 5 mm is sufficient. If the squeeze roller 6 is significantly wider than the copy or drum 1, it is sufficient if the squeeze roller protrudes on the side on which the copy sheet is placed.
  • the result mentioned below is achieved with a squeeze roller 6 which has a cast shell of 8 mm thickness made of polyurethane with a Shore A hardness 27.
  • the 29.5 cm long squeeze roller 6 is pressed in line contact with the photoconductor layer on the drum 1 with a pressure of 2 N / cm and driven at a peripheral speed which was 5% greater than the peripheral speed of the drum 1.
  • a selenium-tellurium alloy 65 ⁇ m thick is used as the photoconductor and charged to +2410 V by the DC corona 2, which is fed with +8 kV.
  • the liquid toner consists of a developer liquid such as Isopar L, an isoparaffinic hydrocarbon with a boiling point of 192 ° C and an Infotec ( R ) toner.
  • the copies obtained are groundless and show a density of 1.1 to 1.2 in the full tone areas.
  • the resolution in the running direction is at least 6.3 lines / mm and transversely to the running direction 5 to 6 lines / mm. With a somewhat lower density of 0.9 to 1.0, the resolution across the direction of travel is also 6.3 lines / mm.
  • the total consumption of liquid developer is determined by weighing the tub 5 of the development station 22 at the start of the measurement and after every 6000 copies. From this weight difference, the proportion by weight is subtracted, which escapes when the copier is operated without adding copy paper due to evaporation of developer liquid in the copier itself.
  • the discharge values for copies according to the present method are about 0.013 g Isopar L per A4 page, while according to the prior art 0.129 g Isopar L per DIN A4 copy will be discharged, ie about ten times the value.
  • a proportion of approximately 0.01 g of developer liquid per A4 copy in a template with 7% coverage appears to be the lower amount of developer liquid that is required to transfer the toner particles deposited on the photoconductor in the process according to the invention to impart the required paste-like consistency to the image-receiving material.
  • the photoconductor layer generally ages when copied in such a way that the maximum charge level decreases with time. With the increased corona voltage of +8 kV used, this aging effect appears somewhat more strongly than with the usual corona voltage of +6.5 kV. The charge level drops from 2350 V to about 1650 V at the end of the endurance test. All in all, it can be said that the higher charge does not stress the photoconductor layer more than the lower charge in conventional copying processes.

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  • General Physics & Mathematics (AREA)
  • Wet Developing In Electrophotography (AREA)

Claims (17)

  1. Procédé de reprographie électrophotographique comportant élimination du liquide développateur d'une surface photoconductrice, dans lequel une couche photoconductrice est chargée électrostatiquement et soumise à une exposition selon l'image support de l'information, dans lequel l'image latente de charge ainsi obtenue sur la couche photoconductrice est développée au moyen d'un liquide développateur pour former une image de toner visible, le liquide développateur excédentaire est éliminé au moyen d'un élément appliqué contre le photoconducteur, l'image de toner est reportée du photoconducteur sur matière réceptrice d'images par électrophorène et fixée sur cette matière, et le photoconducteur est nettoyé et/ou décharge, caractérisé en ce que
    a) la couche photoconductrice est chargée à une tension supérieure à la tension de charge UmaxD qui correspond a la densite de toner maximum,
    b) l'élément appliqué tourne à une vitesse circonférentielle supérieure de 2 à 20 % à la vitesse circonférentielle du photoconducteur et présente des irrégularités de surface de moins de 2 µm de hauteur; et
    c) le transfert de l'image de toner se produit sous une intensité de champ électrique supérieure à celle qui est nécessaire pour le transfert d'images de toner qui sont développées lorsque le photoconducteur est chargé à la tension de charge UmaxD.
  2. 2. Procédé selon la revendication 1, caractérisé en ce que les couches photoconductrices en sélénium sont chargées à une tension supérieure à 1300 volts.
  3. 3. Procédé selon la revendication 1, caractérisé en ce que les couches photoconductrices en sélénium sont chargées à une tension spécifique, c'est-à-dire la tension par unité de longueur de l'épaisseur de la couche photoconductrice, de plus de 25 V/µm.
  4. 4. Procédé selon la revendication 3, caractérisé en ce que les couches photoconductrices en sélénium sont chargées à une tension spécifique atteignant jusqu'à 36 V/p.m.
  5. 5. Procédé selon la revendication 2, caractérisé en ce que les couches photoconductrices en sélénium d'une épaisseur de 50 µm sont chargées à une tension allant jusqu'à 1800 volts.
  6. 6. Procédé selon la revendication 1, caractérisé en ce que le report de l'image de toner du photoconducteur à la matière réceptrice d'images s'effectue avec une tension de report de 7,5 à 8 kV.
  7. 7. Procédé selon la revendication 1, caractérisé en ce que l'élément appliqué est un rouleau essoreur qui tourne avec une vitesse circonférentielle qui est supérieur de 2 à 12 % à la vitesse circonférentielle du photoconducteur.
  8. 8. Procédé selon la revendication 7, caractérisé en ce que le rouleau essoreur est en contact linéaire avec le photoconducteur et est appliqué avec une pression linéaire égale ou supérieure à 0,5 N/cm.
  9. 9. Procédé selon la revendication 8, caractérisé en ce que la pression linéaire entre le rouleau essoreur et le photoconducteur est de 1 à 3 N/cm.
  10. 10. Procédé selon la revendication 7, caractérisé en ce que le rouleau essoreur est nettoyé par une lame d'essuyage.
  11. 11. Dispositif pour la mise en oeuvre du procédé selon les revendications 1 à 10, comprenant une surface photoconductrice qui est chargée électrostatiquement par un dispositif de charge et est exposée selon une image support de l'information par un dispositif d'exposition, pour former une image de charge latente correspondante et, passe successivement par un poste de développement à liquide, un élément servant à éliminer de liquide développateur, un poste de report servant à reporter l'image de toner développée sur une matière réceptrice d'image, un poste de nettoyage équipé d'un dispositif è effet couronne à tension alternative servant à éliminer les charges résiduelles portées par la surface photoconductrice, caractérisé en ce que le dispositif de charge (14) est composé d'un dispositif à effet couronne a courant continu (2) et d'un circuit d'alimentation à haute tension (15) qui est construit pour une tension de service continu de 8 kV, en ce que l'élément (6) destiné à éliminer le liquide développateur est appliqué sous pression contre la surface périphérique du tambour photoconducteur et est en prise par un entraînement à roues dentées (17) avec une roue dentée (18) prévue sur l'arbre (19) d'un tambour photoconducteur (1) de telle manière que la vitesse circonférentielle de l'élément soit supérerieure de 2 à 20 % à la vitesse circonférentielle du tambour photoconducteur (1), lequel est entraîné dans le même sens que l'élément (6) dans la région de contact commune et en ce que le poste de report (16) comprend un dispositif à effet couronne à courant continu (9) possédant une tension de fonctionnement allant jusqu'à 8 kV.
  12. 12. Dispositif selon la revendication 11, caractérisé en ce que l'élément (6) est un rouleau essoreur muni d'une gaine élastique (20) qui présente une surface lisse possédant des irrégularités de préférence inférieure à 1 um et atteignant au maximum 2 µm.
  13. 13. Dispositif selon la revendication 12, caractérisé en ce que l'épaisseur de la gaine (20) est de 4 à 8 mm et que sa dureté Shore est de 25 à 80.
  14. 14. Dispositif selon la revendication 12, caractérisé en ce que l'épaisseur de la gaine (20) est supérieure à 8 mm et la dureté Shore inférieure ou égale à 35.
  15. 15. Dispositif selon la revendication 12, caractérisé en ce que le rouleau essoreur (8) est coulé.
  16. 16. Dispositif selon la revendication 15, caractérisé en ce que le matériau de la gaine (20) du rouleau essoreur (8) est un polyuréthane avec addition d'oxyde de fer et possède une dureté Shore de 27.
  17. 17. Dispositif selon la revendication 12, caractérisé en ce que le rouleau essoreur (8) est plus long que le tambour photoconducteur (1) et déborde au-delà de la surface frontale du tambour photoconducteur (1) au moins sur un côté.
EP83103347A 1982-04-15 1983-04-06 Procédé de tirage électrophotographique et dispositif pour ôter le liquide de développement d'une surface photoconductrice Expired EP0092107B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3213797 1982-04-15
DE19823213797 DE3213797A1 (de) 1982-04-15 1982-04-15 Elektrofotografisches kopierverfahren und vorrichtung zum entfernen der entwicklerfluessigkeit von einer fotoleiteroberflaeche

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EP0092107A1 EP0092107A1 (fr) 1983-10-26
EP0092107B1 true EP0092107B1 (fr) 1986-06-11

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US (1) US4482242A (fr)
EP (1) EP0092107B1 (fr)
JP (1) JPS58187980A (fr)
AU (1) AU551303B2 (fr)
CA (1) CA1205126A (fr)
DE (2) DE3213797A1 (fr)

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AU1324383A (en) 1983-10-20
DE3364049D1 (en) 1986-07-17
DE3213797A1 (de) 1983-10-20
AU551303B2 (en) 1986-04-24
JPS58187980A (ja) 1983-11-02
CA1205126A (fr) 1986-05-27
US4482242A (en) 1984-11-13
EP0092107A1 (fr) 1983-10-26

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