EP0040128A2 - Verfahren zur elektrographischen Reproduktion auf einem Träger unter Verwendung eines magnetischen einkomponentigen Entwicklungstoners - Google Patents

Verfahren zur elektrographischen Reproduktion auf einem Träger unter Verwendung eines magnetischen einkomponentigen Entwicklungstoners Download PDF

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Publication number
EP0040128A2
EP0040128A2 EP81400672A EP81400672A EP0040128A2 EP 0040128 A2 EP0040128 A2 EP 0040128A2 EP 81400672 A EP81400672 A EP 81400672A EP 81400672 A EP81400672 A EP 81400672A EP 0040128 A2 EP0040128 A2 EP 0040128A2
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EP
European Patent Office
Prior art keywords
image
powder
dielectric liquid
support
photoconductive
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
EP81400672A
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English (en)
French (fr)
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EP0040128B1 (de
EP0040128A3 (en
Inventor
Donald Kings
Jean-Claude Marckmann
Quang Pham Kim
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.)
Rhone Poulenc Systemes SA
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Rhone Poulenc Systemes SA
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Publication date
Application filed by Rhone Poulenc Systemes SA filed Critical Rhone Poulenc Systemes SA
Priority to AT81400672T priority Critical patent/ATE15558T1/de
Publication of EP0040128A2 publication Critical patent/EP0040128A2/de
Publication of EP0040128A3 publication Critical patent/EP0040128A3/fr
Application granted granted Critical
Publication of EP0040128B1 publication Critical patent/EP0040128B1/de
Expired legal-status Critical Current

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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G13/00—Electrographic processes using a charge pattern
    • G03G13/14—Transferring a pattern to a second base
    • G03G13/16—Transferring a pattern to a second base of a toner pattern, e.g. a powder pattern

Definitions

  • the present invention relates to a method of electrographic reproduction on any support using a single-component magnetic developing powder. It relates more particularly to an electrographic reproduction method in which an image of electrostatic charges formed on an intermediate support, such as a photoconductor or any other surface capable of retaining an image of electrostatic charges, is developed using a single-component magnetic developing powder to form a powder image which is transferred under the action of electrical means (electric field, discharge device with crown effect, etc.) onto any support, the image thus obtained being fixed by pressure or by heat.
  • electrical means electrical field, discharge device with crown effect, etc.
  • a uniform charge of a photoconductor is generally produced using a corona discharge device (hereinafter called "corona" device): by selective exposure from an original, a charge image which is then developed using a developing powder.
  • corona a corona discharge device
  • one-component developing powders has not only developed in the case of powders of a magnetic nature.
  • powders of the non-magnetic single-component type such as those described in French Patent No. 2,362,428 and to which the invention also applies.
  • Developing powders of the single-component type and in particular those having a magnetic character have the advantage of not polluting the machine in which they are used, because they are permanently maintained on the magnetic brush.
  • These powders are currently widely used in so-called "direct” processes, that is to say by the development of zinc oxygen photoconductive papers with which they give full satisfaction.
  • the present invention provides a solution to this problem and makes it possible to avoid the drawbacks associated with the use of one-component developing powder.
  • the method according to the invention is characterized in that the image support is coated, before the transfer of the powder image, with a thin layer of volatile dielectric liquid, with a volume resistivity greater than 10 3 Q c m 2 / cm, said liquid being present on the support for at least the time interval necessary for the transfer of the image of powder onto said support.
  • a volume resistivity liquid will be used greater than 10 7 ⁇ x cm 2 / cm and even better results are obtained when it is greater than 1 0 10 Q x cm 2 / c m. However, it is around 10 15 ⁇ x cm 2 / cm of volume resistivity that the best results are observed.
  • Such a method makes it possible, surprisingly, to obtain images of clearly improved quality compared to those obtained, all other things being equal, in the absence of dielectric liquid.
  • a method makes it possible to use any support, even a very conductive one such as a metal, as will be seen below, while obtaining an image of excellent quality, having good density and excellent sharpness (by explosion phenomenon).
  • the Applicant thinks, without wishing to be bound by a theory, that the particles of relatively conductive developing powder, when they are transferred into an electric field on a surface of dielectric nature cannot instantly exchange their induced charge when they come into contact with the receiver. As a result, they remain attracted to this surface, which increases the amount of developer powder transferred.
  • the particles of developing powder are themselves wetted by the dielectric liquid, which contributes to limiting the exchange of charges between them and the copy medium: the parasitic discharges which generate the explosion of the image are deleted.
  • the charge carried by the particle can be canceled: the particle is no longer retained, it is pushed out of the image area or towards the photoconductor , which generates the deteriorations noted above.
  • one-component relatively conductive developing powder means an electrographic image developing powder in which only one type of particle is present and having a volume resistivity less than or at most equal to 10 15 ⁇ x cm 2 / cm. Indeed, beyond this value, there is no longer any notable improvement in the quality of the image transferred in the presence of the volatile dielectric liquid.
  • the invention also extends to mixtures of powders as defined above, of various resistivity and particle size.
  • the improvement of the transferred image is entirely satisfactory for a resistivity of between 10 and 10 15 Q x cm 2 / cm.
  • P r e ference use of developing powder having a resistivity between 10 8 and 10 13 ⁇ x cm 2 / cm.
  • the resistivity of the developing powder is measured in a cylindrical cell of section 0.07 cm on a 2 mm thick sample under a pressure of 750 g / cm 2 and under a continuous electric field of 1000 V / cm.
  • the image support according to the present invention can be any, that is to say having a surface resistivity less than 10 13 ⁇ cm 2 / cm.
  • Low resistivity supports such as metal supports are also suitable in the context of the present invention.
  • different products can be produced by applying the method according to the invention.
  • hydrophilic supports treated polyester, metal, coated paper, etc.
  • lithographic printing plates are produced directly using ink-absorbing toners.
  • projectable "transparencies" or negatives can be produced directly.
  • Dielectric liquids with volume resistivity as defined above must not be too volatile so that they are always present on the copy medium at the time of the transfer of the powder image, but also sufficiently volatile to evaporate fast enough so that the copy comes out of the machine.
  • a liquid having a volatility index of between 0.01 and 0.4 will be used.
  • liquid volatility index is meant the quotient of the evaporation time on n-butyl acetate filter papers by the evaporation time of the selected dielectric liquid.
  • means are provided for drying the support before or after fixing the image.
  • These means can for example be combined with the fixing means when using hot fixing rollers.
  • infrared fixing means will be used which perform fixing and drying functions.
  • These means can also be separated when cold fixing is carried out: for example when using pressure rollers, infrared tubes or hot air will be used for drying. It will generally be desirable to provide ventilation to vent the vapors given off. In many cases, however, these drying means are not necessary when the liquid used has suitable volatility.
  • this dielectric liquid must properly wet the copy medium on which the transfer takes place so that a thin layer of liquid is effectively present at all points of the medium during the transfer.
  • the dielectric liquid pure or mixed aliphatic hydrocarbons, branched or not, the boiling points of which range between 60 ° C. and 230 ° C. and preferably between 100 ° C. and 200 ° C. will be used.
  • the dielectric liquids used will not be solvents for the photoconductive layer in order to avoid damaging the latter.
  • these liquids will not be solvents for the resins used for the production of the developing powder so as not to cause even partial softening of the toner which would then be liable to be fixed on the photoconductive layer in a detrimental manner.
  • the quantity of liquid deposited on the copy medium depends in particular on the speed of travel of the copy medium, the nature of the latter (porosity, etc.) as well as the nature of the dielectric liquid (evaporation rate, etc.). It also depends on the distance between the means for coating the liquid on the support and the place of transfer of the powder image. In general, it has been found that an amount of liquid of between 0.1 g / m 2 and 16 g / m makes it possible to achieve the desired result. However, in most cases, it is found that an amount of dielectric liquid of between 2 g / m and 5 g / m gave excellent results, in particular when the powder image was fixed by pressure and Cold.
  • the transfer of the image of developing powder onto the copy medium is carried out according to the devices used and the nature of the copy medium under the action of an electric field or a corona effect device.
  • the parameters which require the use of one or the other transfer means as well as the voltages used are well known to those skilled in the art.
  • the invention presents a preferred variant with a device with three superimposed rollers, the upper roller being the photoconductor on which the powder image is produced, the two lower rollers being rollers metallic, the adjacent or photoconductive roller receiving the powder image, while the transfer of the latter onto any support is effected by pressure between the two rollers.
  • the upper roller being the photoconductor on which the powder image is produced
  • the two lower rollers being rollers metallic
  • the adjacent or photoconductive roller receiving the powder image while the transfer of the latter onto any support is effected by pressure between the two rollers.
  • it has been found that it is preferable to partially discharge, in particular by light radiation, the photoconductor before transferring the powder image, under the action of a field. electric, on the adjacent metal roller coated with dielectric liquid.
  • the magnetic brush 15 magnetically retains on its surface, the single-component magnetic toner which forms chains in grains such as 22.
  • the charges 23 of the charge image, formed on the photoconductor 9, approach grains of developing powder become polarized by influence.
  • the part of the grain, opposite the negative charge 23 takes an equal positive charge.
  • the electrostatic force between these two charges is then sufficient, due to the presence of the electric field created by the image of charges, to attract the grains of powder to the photoconductor 9, thus forming the image of powder 20.
  • the figures 2a, 2b and 2c are shown the three best known variants for transferring a loaded developer powder onto a support.
  • the polarities of the voltages are relative to positively charged particles, as explained in FIG. 1. It is obvious that the polarities of the voltages must be reversed in the case where the developing powder charges negatively.
  • the cylinder 10 connected to a voltage source positive is covered with a photoconductor 9 on which is a powder image. 20 which must be transferred to the copy medium 5 which moves on the grounded guide medium 4.
  • the particles of developing powder are transferred to the copy medium under the action of the electric field existing between the photoconductive drum and the medium 4 and directed towards the latter.
  • the copy medium has the form of a conductive cylinder connected to ground, the transfer being improved by the pressure contact existing between the photoconductive drum and the cylinder 4.
  • the copy supports 2 stored in a cassette 1 are engaged on the support 4 when the user wishes to make a copy.
  • the copy support 5, already engaged is coated with a layer of dielectric liquid 8, contained in the reservoir 7, using the coating device 6.
  • the powder image is formed on the photoconductor 9 which covers the metal roller 10 connected to a positive voltage source, in the case where the toner is positively charged by influence.
  • a corona effect device 13 deposits a uniform charge on the photoconductor 9.
  • the charge image is developed using the magnetic brush 15 and the forms a powder image 20. This is transferred at 21 to the support 5 under the action of the positive voltage existing between the photoconductive roller 10 and the support 4 grounded.
  • the image is then fixed in the infrared oven 11 and the copy recovered in the tray 12.
  • FIG. 4 illustrates a particularly interesting embodiment of the invention and with which certain examples given below have been produced.
  • the same means have the same references as in the previous figures.
  • Powder image 20 is formed with the same means and in the same way as in FIG. 3.
  • the powder image 20 is then transferred at 21 to the grounded metal roller 16.
  • This roller 16 is previously coated using the coating device 17 with dielectric liquid as defined above.
  • the image of powder thus transferred is then transferred again by pressure, onto the copy medium 5 which advances thanks to the rotation of the two rollers 16 and 18, the pressure of which also fixes the powder image 20.
  • the pressure between the rollers 16 and 18 is approximately 30 kg / linear cm.
  • the lighting device 25 ensures partial discharge of the photoconductor before transferring the image, when this is necessary.
  • the lighting device 24 makes it possible to completely discharge the photoconductor 9 before cleaning with the magnetic brush 29.
  • FIG. 5 represents an alternative embodiment of the invention specially intended for the reproduction of microfilmed images.
  • a photoconductive strip 9 will be used on which the image will be projected completely.
  • the charge image is then developed using the brush 15 and transferred as in FIG. 4, onto a metal roller 16 coated with dielectric liquid using the coating system 17.
  • a counter-roller 50 on the other side of the photoconductive strip.
  • the other elements have the same meaning as those in Figure 3.
  • Figure 6 shows a prototype of a device according to the invention, wherein the same elements as those of FIGS PREVIOUS - dentes bear the same references.
  • the image of charges on the photoconductor 9 (under which a layer of foam 49 can be placed but which is preferably rigid on the surface) is produced using the image block 30 and the optics 14 after uniform loading using corona 13.
  • the image is developed using the developing powder 31 deposited uniformly on the brush 15 using the doctor blade 32.
  • the photoconductor is then partially discharged using lighting means 33 whose intensity is adjustable using a flap 35 articulated around the axis 34 using a cam 36.
  • the image is then transferred to the roller 16 previously coated with dielectric liquid, contained in the reservoir 37, using the brush 17.
  • the powder image is dried by hot air sent by the fan 44 in the duct 46, the photoconductor also being dried by the hot air arriving in the duct 45.
  • the image is then transferred and fixed by pressure using the two rollers 16 and 18 on the copy medium 5. This this is detached from the cylinder 16 using the doctor blade 39, the said cylinder then being cleaned using the brush 40.
  • the cylinder 18 is cleaned by the brush 41.
  • the photoconductor is discharged using the means d 'illumination 24, after transfer of the image, then cleaned using the magnetic brush 47. The excess powder on this brush is recovered in the tray 48.
  • This example is carried out using a SHARPFAX SF 730 machine using a zinc oxide photoconductive surface, a single-component magnetic developer and a cold pressure fixing between two metal rollers.
  • the machine is used at 20 ° C and 65% relative humidity, the copy medium being ordinary paper commercially available under the name VOIRON VELIN SH.
  • a single-component magnetic developer HMT 824/4 is used, sold by the company HITACHI METALS Ltd, with a volume resistivity, measured according to the above-mentioned method, equal to 3 ⁇ 10 10 Q cm / cm.
  • the original to be reproduced is a screen having different ranges varying from 1 line per mm to 6.3 lines per mm and also having uniform parts enabling the optical density of the image to be measured.
  • the quality of the image obtained is poor: there is a tendency for the line to burst and a fairly average contrast of the image.
  • This dielectric liquid has a resistivity of 5 x 1 0 14 Q x cm 2 / cm at 20 ° C and a volatility index of 0.18.
  • the quantity of liquid deposited on the paper is approximately 3.2 g / m 2 . All the test parameters are the same as before.
  • the sheet of paper is then immediately introduced into the paper tray of the SHARP SF 730 machine, and a printout is performed as before.
  • the comparison of the two images obtained with and without dielectric liquid shows a marked improvement in the quality of the image when the dielectric liquid is used.
  • the definition obtained in this case is 4.5 lines per mm and the image density is 1.61.
  • Example 1 The same test is carried out as in Example 1 using a matte polyester copy medium intended for the graphic arts and sold under the trade name REGMA FM by the company RHONE-POULENC SYSTEMES.
  • HMT 808 developer powder from HITACHI METALS Ltd. is used. Copying without dielectric liquid is unusable in practice, because the image is blurred, blurred, heterogeneous.
  • ISOPAR G dielectric liquid depositing on this support before copying, an image of amazing quality is obtained by its homogeneity and its sharpness.
  • the improvement obtained is a function of the quantity of dielectric liquid deposited. This example also makes it possible to measure the influence of the quantity of liquid deposited, since the absorption of this type of support is zero.
  • Example 1 The procedure is as in Example 1 using the developing powder supplied with the SHARP SF 730 machine, with a resistivity of 8.3 ⁇ 10 9 Q ⁇ cm 2 / cm by treating the VOIRON SH paper using iso- dodecane with a resistivity equal to 1 x 10 15 ⁇ x cm 2 / cm and the volatility coefficient of which is 0.22.
  • This draw is compared to that obtained, all other things being equal, in the absence of dielectric liquid.
  • the device in FIG. 2b is used to transfer the image 20 to the copy medium 5.
  • the cylinder 10 will be coated with a layer of flexible foam of a few millimeters before having the photoconductive strip 9 on the outside. In this case, the quality of the transfer of the image.
  • the charge image formed on the photoconductor is developed using HITACHI HMT 403 toner with a resistivity close to 10 12 Q x cm 2 / cm.
  • the powder image is transferred under 400 V, after partial discharge of the photoconductor, onto a grained aluminum sheet for CRAO reference lithography (from the company AGFA-GEVAERT).
  • Example 5 The experiment of Example 5 is repeated using a heat-fixable magnetic toner HMT 403, from the company Hitachi with a neighboring resistivity of 10 12 Q x c m 2 / cm.
  • the transfer is carried out at a voltage of 400 V, the photoconductor being partially discharged before transfer.
  • the image is transferred to VOIRON VELIN SH paper previously described. In the absence of dielectric liquid, the image is transferred at 80%, but it is blurred.
  • SHELL SOL T from the company SHELL OIL Cy
  • the device shown schematically in FIG. 4 and shown in more detail in FIG. 6 is used, with a zinc oxide photoconductor (dual-charge paper REGMA M 100 BC) developed with the toner H MT 824/4 mentioned above.
  • the receiving support is VOIRON VELIN SH paper. The transfer takes place at a voltage of 300 V. by partially discharging the photoconductor.
  • the same device is used as in the previous example, the image being developed with a HITACHI HMT 824/4 toner, the support to which the image is transferred being a REGMA FM polyester film, at 300 V of voltage and after partial discharge of the photoconductor.
  • the device of FIG. 3 is used in which the photoconductive strip is of the REGMA M 100 BC type.
  • This photoconductive surface has the distinction of being dual charge, that is to say, to accept both positive charges and negative charges. It is therefore possible, with this type of photoconductor, to carry out an inverted development of the image, that is to say, deposit the monocomponent powder on the discharged areas of the photoconductor, by applying a positive voltage to the magnetic brush. 300 V with respect to the support of the photoconductive surface, the photoconductor having an image of positive charges.
  • the resistivity of the toner is measured according to the method mentioned above. Illumination is the operation which consists in discharging more or less the photoconductor after development of the image, but before transfer of this one. In the absence of dielectric liquid, the results obtained are as follows:
  • This example shows the improvement obtained in the quality of the image for a given toner, a given transfer voltage, for a given partial discharge of the photoconductor before image transfer, as a function of the resistivity of the dielectric liquid used (experiment performed on the device of Figure 3).
  • EXAMPLE 14 making a printed circuit.
  • a REGMA R 220 reference electrophotographic paper sheet is loaded uniformly using a negative sign corona device.
  • the drawing of the printed circuit made on a transparent original is brought into contact with said sheet of paper, the assembly then being exposed to light.
  • the charge image thus formed is then developed using a one-component HMT 403 developing powder.
  • a sheet of copper-coated epoxy glass is then treated with nitric acid in order to give good wettability to the copper-colored face which is then coated on one half with a thin film of ISOPAR G, the other half of the copper-colored face. not being treated.
  • the copper plate is then placed on a grounded metal plate, the copper side up. An electrical contact is established between the metal plate and the copper-colored face which is thus earthed.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Developing Agents For Electrophotography (AREA)
  • Electrostatic Charge, Transfer And Separation In Electrography (AREA)
  • Wet Developing In Electrophotography (AREA)
  • Magnetic Brush Developing In Electrophotography (AREA)
  • Color Electrophotography (AREA)
  • Soft Magnetic Materials (AREA)
  • Hard Magnetic Materials (AREA)
  • Combination Of More Than One Step In Electrophotography (AREA)
  • Photoreceptors In Electrophotography (AREA)
EP81400672A 1980-05-12 1981-04-29 Verfahren zur elektrographischen Reproduktion auf einem Träger unter Verwendung eines magnetischen einkomponentigen Entwicklungstoners Expired EP0040128B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81400672T ATE15558T1 (de) 1980-05-12 1981-04-29 Verfahren zur elektrographischen reproduktion auf einem traeger unter verwendung eines magnetischen einkomponentigen entwicklungstoners.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8010611A FR2482323A1 (fr) 1980-05-12 1980-05-12 Procede de reproduction electrographique sur un support quelconque a l'aide d'une poudre de developpement magnetique monocomposant
FR8010611 1980-05-12

Publications (3)

Publication Number Publication Date
EP0040128A2 true EP0040128A2 (de) 1981-11-18
EP0040128A3 EP0040128A3 (en) 1982-09-15
EP0040128B1 EP0040128B1 (de) 1985-09-11

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EP81400672A Expired EP0040128B1 (de) 1980-05-12 1981-04-29 Verfahren zur elektrographischen Reproduktion auf einem Träger unter Verwendung eines magnetischen einkomponentigen Entwicklungstoners

Country Status (8)

Country Link
US (1) US4373016A (de)
EP (1) EP0040128B1 (de)
JP (1) JPS575068A (de)
AT (1) ATE15558T1 (de)
CA (1) CA1175474A (de)
DE (1) DE3172202D1 (de)
DK (1) DK206381A (de)
FR (1) FR2482323A1 (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2557317A1 (fr) * 1983-12-22 1985-06-28 Rhone Poulenc Syst Procede de reproduction electrophotographique, avec developpement inverse, sur un support conducteur a l'aide d'une poudre de developpement magnetique monocomposant et dispositif pour la mise en oeuvre du procede
EP0297721A1 (de) * 1987-06-01 1989-01-04 Xerox Corporation Zwischenübertragungsgerät
EP0252735A3 (en) * 1986-07-09 1990-04-11 Olin Hunt Specialty Products, Inc. Method of high resolution electrostatic transfer of a high densitiy image to a nonporous and nonabsorbent conductive substrate
EP0373968A3 (en) * 1988-12-16 1990-12-27 Matsushita Electric Industrial Co., Ltd. Printing apparatus
EP0636948A3 (de) * 1993-07-26 1996-02-07 Hewlett Packard Co Verfahren und Vorrichtung zum Auftragen einer Klebschicht zur verbesserten Bildübertragung in der Elektrophotographie.

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4571059A (en) * 1983-10-17 1986-02-18 Minnesota Mining And Manufacturing Company Apparatus for transferring images of conductive toner powder
US4786576A (en) * 1984-09-27 1988-11-22 Olin Hunt Specialty Products, Inc. Method of high resolution of electrostatic transfer of a high density image to a nonporous and nonabsorbent conductive substrate
US4661431A (en) * 1984-09-27 1987-04-28 Olin Hunt Specialty Products, Inc. Method of imaging resist patterns of high resolution on the surface of a conductor
US4569895A (en) * 1984-10-30 1986-02-11 Minnesota Mining And Manufacturing Company Charge transfer media and process for making thereof
US4859557A (en) * 1988-02-25 1989-08-22 Olin Hunt Specialty Products Inc. Dry powder electrophotographic toner with permanent master in electrostatic transfer
US5011758A (en) * 1988-02-25 1991-04-30 Olin Hunt Specialty Products Inc. Use of a liquid electrophotographic toner with an overcoated permanent master in electrostatic transfer
AU607347B2 (en) * 1988-11-15 1991-02-28 Olin Hunt Specialty Products Inc. Method of high resolution electrostatic transfer of a high density image to a nonconductive receiving substrate

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1153586A (en) * 1965-06-28 1969-05-29 Rank Xerox Ltd Formation of Induced Electrostatic Latent Images
US3647499A (en) * 1969-08-19 1972-03-07 Eastman Kodak Co Process for transferring dry developed electrographic images
US3627557A (en) 1969-08-27 1971-12-14 Xerox Corp Liquid development by reducing the viscosity of the developer on a roller applicator prior to development
JPS4934151B1 (de) * 1970-06-04 1974-09-12
US4007041A (en) * 1975-03-10 1977-02-08 Xerox Corporation Electrophotographic printing method
JPS53136836A (en) * 1977-05-04 1978-11-29 Ricoh Co Ltd Electrophotographic transfer method

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2557317A1 (fr) * 1983-12-22 1985-06-28 Rhone Poulenc Syst Procede de reproduction electrophotographique, avec developpement inverse, sur un support conducteur a l'aide d'une poudre de developpement magnetique monocomposant et dispositif pour la mise en oeuvre du procede
EP0147341A3 (de) * 1983-12-22 1985-08-07 Rhone-Poulenc Systemes Verfahren zur elektrophotographischen Reproduktion, mit umgekehrter Entwicklung, auf einem leitenden Bildträger mit Verwendung eines magnetischen Einkomponentigen Entwicklungspulvers und Vorrichtung zur Durchführung des Verfahrens
EP0252735A3 (en) * 1986-07-09 1990-04-11 Olin Hunt Specialty Products, Inc. Method of high resolution electrostatic transfer of a high densitiy image to a nonporous and nonabsorbent conductive substrate
EP0297721A1 (de) * 1987-06-01 1989-01-04 Xerox Corporation Zwischenübertragungsgerät
EP0373968A3 (en) * 1988-12-16 1990-12-27 Matsushita Electric Industrial Co., Ltd. Printing apparatus
US5040027A (en) * 1988-12-16 1991-08-13 Matsushita Electric Industrial Company, Ltd. Printing apparatus
EP0636948A3 (de) * 1993-07-26 1996-02-07 Hewlett Packard Co Verfahren und Vorrichtung zum Auftragen einer Klebschicht zur verbesserten Bildübertragung in der Elektrophotographie.

Also Published As

Publication number Publication date
EP0040128B1 (de) 1985-09-11
FR2482323A1 (fr) 1981-11-13
FR2482323B1 (de) 1985-05-17
EP0040128A3 (en) 1982-09-15
JPS575068A (en) 1982-01-11
ATE15558T1 (de) 1985-09-15
DK206381A (da) 1981-11-13
CA1175474A (fr) 1984-10-02
DE3172202D1 (en) 1985-10-17
US4373016A (en) 1983-02-08

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