EP0687963B1 - Bildaufzeichnungsgerät - Google Patents

Bildaufzeichnungsgerät Download PDF

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Publication number
EP0687963B1
EP0687963B1 EP19950304014 EP95304014A EP0687963B1 EP 0687963 B1 EP0687963 B1 EP 0687963B1 EP 19950304014 EP19950304014 EP 19950304014 EP 95304014 A EP95304014 A EP 95304014A EP 0687963 B1 EP0687963 B1 EP 0687963B1
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EP
European Patent Office
Prior art keywords
medium
image recording
recording apparatus
charge
image
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.)
Expired - Lifetime
Application number
EP19950304014
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English (en)
French (fr)
Other versions
EP0687963A2 (de
EP0687963A3 (de
Inventor
Masakazu C/O Nec Corporation Okuda
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.)
NEC Corp
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NEC Corp
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Filing date
Publication date
Application filed by NEC Corp filed Critical NEC Corp
Publication of EP0687963A2 publication Critical patent/EP0687963A2/de
Publication of EP0687963A3 publication Critical patent/EP0687963A3/de
Application granted granted Critical
Publication of EP0687963B1 publication Critical patent/EP0687963B1/de
Anticipated expiration legal-status Critical
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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
    • G03G15/065—Arrangements for controlling the potential of the developing electrode
    • 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
    • G03G15/32—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 charge pattern is formed dotwise, e.g. by a thermal head

Definitions

  • the present invention relates to an image recording apparatus applicable to a printer, facsimile equipment, a copying machine, and the like and, in particular, to an image recording apparatus in which an electrostatic latent image created according to pyroelectric effect is developed with an electrically charged coloring medium to be transferred and fixed onto a recording medium, thereby obtaining an image on the recording medium.
  • Pyroelectric material has a characteristic in which when the materials are heated, electric charge is collected on surfaces thereof.
  • a pyroelectric material is selectively heated according to information of an image to form an electrostatic latent image thereof such that the latent image is visualized by a toning or coloring medium so as to record the visual image on a recording medium.
  • J. G. Bergman et al have first disclosed a copying device using a pyroelectric substance. According to the U.S.P. No. 3,824,098 of J. G. Bergman et al and in page 497 to 499 of "Applied Physics Letters", Vol. 21 (10) published in 1972, there has been proposed a copying machine in which polymeric polyvinylidene fluoride (PVDF) is adopted as the pyroelectric material. In the facility, as shown in Fig.
  • PVDF polymeric polyvinylidene fluoride
  • a light beam illuminated from a lamp namely, a light source 46 is passed through a sheet of manuscript 45 to be irradiated onto a laminated plate including a pyroelectric layer 43 and an electrically conductive layer 44 so as to heat the plate according to an image pattern produced by the light beam. Due to pyroelectric effect, electric charge of the latent image is collected on the surface of the pyroelectric layer 43 and then is developed with electrically charged particles of toner 47 into a toner image. The toner image is subsequently copied onto, for example, a sheet of recording paper to obtain a copied image of the manuscript.
  • the device includes a latent image charge keeping medium 31 for keeping thereon electric charge of a latent image.
  • the medium 31 includes a pyroelectric film 32 and an electrically conductive film 33.
  • the charge keeping medium 31 is heated by a heating element array (heating needle) 34 under supervision of a controller 36.
  • the image 37 is developed by a developing device 38 using a toner to be thereafter transferred onto a sheet of recording paper 40 by transferring means 41 so as to form an image 42 on the recording sheet 40.
  • the transferred particles of toner are fixed onto the sheet 40 by a fixing apparatus (not shown).
  • the conventional image recording apparatuses are attended with difficulty in that variation in temperature of the heating means or chanae in the environmental temperature causes non-uniformity in the final recording density, leading to deterioration in quality of the recorded image.
  • variation in temperature of the heating means or chanae in the environmental temperature causes non-uniformity in the final recording density, leading to deterioration in quality of the recorded image.
  • the temperature of the heating means is increased (due to heat accumulation) or the environmental temperature becomes higher in the apparatus, there occurs a problem that an excessive recording density appears in the attained image or a foggy portion takes place due to toner particles attached onto non-image areas in the recorded picture.
  • a thermal head is adopted as the heating means and the temperature thereof is generally increased by 10 °C due the heat accumulation and/or alteration in the environmental temperature.
  • the base temperature of the thermal head is increased, there appear two primary influences upon the recorded image.
  • the control operation of the amount of heat created from the heating means has nothing to do with the effect of the correction with respect to the temperature rise in the non-image area.
  • the control operation is effective in the thermal recording operation.
  • the thermal recording operation has a unique characteristic that the recording operation (transfer of ink) is carried out only when the temperature of ink is at its melting point or more.
  • an image recording apparatus comprising a latent image charge keeping medium including a pyroelectric layer, heating means for selectively heating the charge keeping medium according to a video signal and forming an electrostatic latent image, developing means for visualizing the electrostatic latent image on the medium with an electrically charged toning medium, thereby visualizing the latent image, means for sensing at least temperature of the heating means, temperature of the medium, and environment temperature, and means of controlling, according to data of the obtained temperature, an amount of the toning medium supplied from the developing means onto the charge keeping medium.
  • the means for controlling the amount of the toning medium is a bias voltage controller supervising a developing bias voltage applied to the developing means.
  • the latent image charge keeping medium including the pyroelectric layer is locally heated by the heating means according to a video signal.
  • the state of orientation of molecules is altered in the pyroelectric layer. This resultantly causes latent image charge to appear on the surface of the pyroelectric layer.
  • the toning medium When the charge keeping medium in which the latent image is created is in the proximity of or is brought into contact with a charged toning medium, the toning medium is selectively attached onto the surface of the pyroelectric medium so as to visualize or develop the latent image.
  • the amount of the toning medium supplied from the developing means is controlled to attain a favorable record image. That is, the amount of the toning medium is set to an optimal value according to data of at least either one of the heating temperature, temperature of the charge keeping medium, and the environmental temperature in the apparatus, the temperature data being obtained from temperature sense means.
  • the amount of the supplied toning medium is supervised, for example, by a bias voltage applied to the developing means. Namely, in case where the charge keeping medium is excessively heated due to heat accumulation of the heating means, the bias voltage applied to a developing electrode of the developing means is increased in the direction of the polarity of latent image charge to thereby minimize the potential difference between the latent image and the developing means. When the potential contrast is reduced in the developing step, the amount of the toning medium attached onto the charge keeping medium is minimized. This resultantly suppresses the excessive increase in the recording density and prevents the excessive amount of the coloring medium (causing the foggy portion) from being attached on the non-image area.
  • Fig. 3 shows constitution of a first embodiment of the image recording facility in accordance with the present invention.
  • the image recording device of this embodiment includes a latent image charge keeping medium 3 in an endless belt shape, a thermal head 4, a conductive film 5, a temperature sensor 21, a bias voltage controller 22, a developing device 7 as developing means, a transfer roller 12, and a fixing device 15.
  • the charge keeping medium 3 includes two layers, namely, a pyroelectric layer 1 (about 30 micrometer ( ⁇ m) thick) and an electrically conductive layer 2 (about 500 angstrom (A) thick), which are configured in an endless belt contour.
  • the layers 1 and 2 are made of polyvinylidene fluoride (PVDF) and aluminum, respectively.
  • the conductive layer 2 is kept at a ground potential through a conductive roller 20.
  • the thermal head 4 employed as the heating means in this embodiment is a line-type thermal head generally utilized for the thermal recording operation.
  • fine heating elements to generate Joule heat are arranged with a pitch of about 83 ⁇ m (300 dots/inch) along lines in the direction of width of the charge keeping medium 3.
  • These heating elements are selectively initiated by a controller 16 in response to video signals to heat the charge keeping medium 3.
  • an electrically conductive layer 5 is formed to cover the heating section.
  • the layer 5 neutralizes electric charge on the surface of the pyroelectric layer 1 in the heating state thereof.
  • a pyroelectric layer 51 of the charge keeping medium has electric charge on a surface thereof due to spontaneous polarization of molecules of the layer 51.
  • the surface charge is in the neutral state (Fig. 4A). That is, floating charge existing in the air and charge 53 supplied from neutralizing means such as an electrically conductive brush fix onto the surface of the pyroelectric layer 51 to establish the electrically neutralized state.
  • neutralizing means such as an electrically conductive brush fix onto the surface of the pyroelectric layer 51 to establish the electrically neutralized state.
  • the polarized charge appearing on the surface of the pyroelectric layer 51 has the positive polarity and true effective charge attached onto the surface has the negative polarity.
  • the polarized state is also restored to the original state in the pyroelectric layer 51.
  • the surface of the pyroelectric layer 51 has already been separated from the charge neutralizing means. Consequently, the negative charge is insufficient on the pyroelectric layer surface.
  • the surface is positively charged as a result (Fig.4D). Namely, in the heated portion of the charge keeping medium, a positive-polarity latent image is created after the charge keeping medium is cooled down.
  • the latent image thus obtained is gradually vanished because floating charge existing in the air is collected onto the image.
  • the phenomenon takes a long period of time and hence the latent image is kept retained for several hours to several tens of hours in ordinary cases.
  • an electrically conductive layer 5 is formed as the charge neutralizing means.
  • a thin metallic film of aluminum or chrome having a thickness of about 1000 angstroms is fabricated on the thermal head surface by evaporation.
  • Figs. 5 and 6 shows constitution of the thermal head 4 and the conductive layer 5. Specifically, Fig. 6 shows a cross section of the construction along direction VI of Fig. 5.
  • the thermal head 4 includes a ceramic substrate 401 and a resistive layer 402 formed thereon as a heating section. Disposed on the resistive layer 402 are electrodes 403 and 404 to oppose to each other with a predetermined interval therebetween. A portion of the resistive layer 402 between the electrodes 403 and 404 functions as the heat generating section. Namely, when an electric current flows between the electrodes 403 and 404, the heating section of the layer 402 generates heat.
  • the resistive layer 402 provides a string of heating elements on the thermal head 4.
  • the conductive layer 5 is formed along a longitudinal central line of the resistive layer 402 forming the heating element string.
  • the conductive layer has a width of about four millimeters (mm) in the direction of width of the heating element string. However, the width may be four mm or less or four mm or more only if the conductive layer 5 covers the heat generating section.
  • the material and structure of the charge neutralizing means are not restricted by those of the embodiment above. Namely, there may be employed other substances and configurations thereof.
  • the means may include a thin film made of a conductive organic material and a configuration in which a conductive film is interposed between a thermal head and a pyroelectric layer.
  • the heated medium 3 is naturally cooled down to the room temperature to produce a latent image 17.
  • a forced cooling step or forced cooling means utilizing, for example, thermal conduction to a heat sink.
  • the latent image 17 created on the medium 3 is visualized or developed by the developer 7.
  • the developer 7 carries out the so-called two-component magnetic brushing operation. Namely, there is employed a developing agent 8 containing insulating and non-magnetic toner particles mixed with magnetic carrier particles to electrically charge the toner particles by friction therebetween so that the toner particles are fixed onto carrier particle surfaces.
  • the developing agent 8 is kept applied onto a sleeve 10 with a magnet roller 9 disposed therein. When the agent 8 is brought into contact with the charge keeping medium 3, the toner is selectively fixed onto the surface of the medium 3 according to the charge distribution thereon, thereby forming a visual image.
  • the sleeve 10 is applied with a bias voltage from a bias voltage controller 22.
  • the bias voltage is controlled according to a representative temperature of the thermal head 4 obtained from a temperature sensor (thermistor) 21. That is, the bias voltage is selected to prevent the toner from fixing onto the non-image area even when latent image charge appears thereon.
  • Fig. 7 shows details of the bias voltage controller 22, which includes temperature sensors 21, 21a, and 21b to control the bias voltage to be applied to the sleeve 10.
  • the sensor 21 senses temperature of the thermal head 4.
  • the sensor 21a detects the environmental temperature, namely, the environmental temperature in the apparatus; whereas the sensor 21b measures temperature of the charge keeping medium 3.
  • Sensed data items are transmitted from the sensors 21, 21a, and 21b respectively to analog-to-digital (A/D) converters 201 to 203 to be converted into digital signals, which are then sent to a central processing unit (CPU) 204.
  • the CPU 204 decides the largest value among the data items from the sensors 21, 21a, and 21b to produce a control signal according to the maximum temperature value.
  • the control signal is then transformed into an analog signal by a digital-to-analog converter 205 to be supplied to a direct-current (dc) power source 206. This signal controls the value of voltage outputted from the dc power source 206, namely, the bias voltage to the sleeve 10.
  • the CPU 204 may obtain a mean value of the outputs from the sensors 21, 21a, and 21b in place of the maximum temperature value. Moreover, the CPU 204 carries out such processes including a time control (delay) operation in the voltage control process of the dc power supply 206.
  • the medium 3 is fixed onto a sheet of recording paper 11 as a recording medium. Thereafter, to electrostatically transfer the toner onto the surface of the recording sheet 11, the recording sheet 11 is pushed by the transfer roller 12 on a rear surface thereof.
  • a voltage of about +1 kV is applied to the conducutive gum roller to effect the electrostatic transfer of the tone.
  • the recording sheet 11 onto which the toner has been transferred is passed through the fixing facility 15 including a heater roller 13 and a pressure roller 14 such that the toner is once fused on the sheet surface, thereby fixing the toner on the recording sheet 11.
  • the method of developing the latent image, kind of the developing agent, method of transferring the toner agent onto the recording medium, and method of fixing the toner onto the recording medium are not limited to those used in the embodiment. That is, the similar advantageous effect can be obtained according to other conventional methods utilized in electrophotography.
  • the charge keeping medium 3 is again returned to the latent image creating section (thermal head section) to generate a subsequent latent image.
  • the toner is removed by a cleaner (not shown) when necessary.
  • charge removing means such as an electrically conductive brush (not shown) when necessary.
  • the charge removing means is grounded in operation to be brought into contact with the surface of the pyroelectric layer 1 so as to easily neutralize the charge remaining on the surface of the pyroelectric layer 1, thereby restoring the charge keeping medium 3 to the initial state.
  • Results of recording experiments conducted in the image recording device structured as above lead to confirmation that favorable pictures free of the foggy portion can be attained through a continuous recording operation. Moreover, also in case where a gray-scale recording operation is conducted while controlling temperature of the heating elements of the thermal head, it has been confirmed that the recording operation is effected with a highly stable recording density to obtain a high-quality picture.
  • Fig. 8 shows constitution of an alternative embodiment of the image recording device in which the latent image generating and developing processes are simultaneously carried out in accordance with the present invention.
  • the constituent elements of the apparatus are almost the same as those of the first embodiment of Fig. 3 and hence are assigned with the same reference numerals.
  • the charge keeping medium 3 is heated by the thermal head 4 pushed against the side of the conductive layer 2 of the medium 3.
  • This embodiment includes the developing device 7 opposing to the thermal head 4 such that the developing of a latent image is simultaneously achieved while the medium 3 is being heated.
  • the complicated process of creating a latent image as described in conjunction with the first embodiment is unnecessary. That is, in the heated portion of the medium 3, the state of orientation of the molecules alters in the pyroelectric layer, which consequently reduces the amount of polarized charge appearing on the surface of the pyroelectric layer. As result, the amount of true effective charge fixed on the surface becomes excessive (Fig. 4B).
  • the toning medium When a toning medium charged to a polarity opposite to that of the excessive charge is brought into contact with or is in the proximity of the excessive charge, the toning medium is attached onto the surface of the pyroelectric layer, thereby visualizing of the latent image.
  • a toner agent charged to the positive polarity is employed as the coloring agent.
  • the structure of the developing facility is the same as that shown in first embodiment.
  • the sleeve 10 of the developer 7 is applied with a bias voltage from the bias voltage controller 22.
  • the bias voltage is supervised according to information of temperatures measured by the temperature sensor 21 to sense accumulated heat of the thermal head 4, the temperature sensor 21a to measure temperature in the apparatus, and the temperature sensor 21b to detect temperature of the charge keeping medium 3.
  • a desired image 19 can be recorded on the recording sheet 11.
  • the latent image charge keeping medium is in the form of a belt in the embodiments.
  • the similar advantages can also be attained by use of the medium in any other form, for example, that of a drum or flat plate.
  • the recording medium in the embodiments above, there may be naturally adopted various types of recording media in accordance with the present invention.
  • the transfer and fixing steps of the toning medium onto the recording medium may be dispensed with. That is, the present invention, is also applicable to apparatuses such as an indication board in which the toning medium is temporarilly kept retained on the recording medium so as to display information thereon for a predetermined period of time.
  • coloring particles i.e., powdered toner particles
  • any other coloring media such as a liquid toner and a liquid ink.
  • a method of applying a bias voltage to the developing means is employed in the embodiments.
  • other methods may also be used, for example, the number of rotation of the developing sleeve or the magnitude of charge of the toning medium may be supervised for the control of the amount of the coloring medium.
  • the recording density can be kept retained and the foggy portion is suppressed in the picture, thereby achiving a high-quality image recording operation.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Electrophotography Using Other Than Carlson'S Method (AREA)
  • Electronic Switches (AREA)

Claims (14)

  1. Bildaufzeichnungsgerät mit einem eine pyroelektrische Schicht (1) aufweisenden Latentbild-Ladungserhaltungsmedium (3); einer Erwärmungseinrichtung (4) zum selektiven Erwärmen des Ladungserhaltungsmediums (3) gemäß einem Videosignal; und einer Entwicklungseinrichtung (7) zum Sichtbarmachen eines auf dem Ladungserhaltungsmedium (3) ausgebildeten elektrostatischen Latentbildes mit einem geladenen Tonermedium (8);
       dadurch gekennzeichnet, daß das Gerät ferner aufweist;
    eine Einrichtung (21, 21a, 21b) zum Messen der Temperatur zumindest von einem von der Heizeinrichtung (4), dem Ladungserhaltungsmedium (3) und der Umgebung in dem Gerät; und
    eine Einrichtung (22) zum Steuern einer Menge des von der Entwicklungseinrichtung (7) an das Ladungserhaltungsmedium (3) gelieferten Tonermediums gemäß den Daten der erhaltenen Temperatur.
  2. Bildaufzeichnungsgerät nach Anspruch 1, wobei die Einrichtung (22) zum Steuern der Menge, des Tonermediums eine Vorspannungssteuerung zum Steuern einer an die Entwicklungseinrichtung (7) angelegten Vorspannung ist.
  3. Bildaufzeichnungsgerät nach Anspruch 1, wobei das Latentbild-Ladungserhaltungsmedium (3) eine leitende Schicht (2) aufweist und die leitende Schicht (2) auf Massepotential gehalten wird.
  4. Bildaufzeichnungsgerät nach Anspruch 3, wobei das Latentbild-Ladungserhaltungsmedium, (3) die Form eines Endlosbandes aufweist.
  5. Bildaufzeichnungsgerät nach Anspruch 1, wobei die Erwärmungseinrichtung (4) ein Thermokopf (4) ist, und der Thermokopf (4) ein Substrat (401), eine auf dem Substrat ausgebildete Widerstandsschicht (402), auf der Widerstandsschicht (402) angeordneten Elektroden (403, 404) und eine auf den Elektroden (403, 404) und der Widerstandsschicht (402) ausgebildete isolierende Schulzschicht (405) aufweist.
  6. Bildaufzeichnungsgerät nach Anspruch 1, ferner mit einer Einrichtung (5) zum Neutralisieren elektrischer Ladung auf der Oberfläche der pyroelektrischen Schicht (1).
  7. Bildaufzeichnungsgerät nach Anspruch 5, ferner mit einer Einrichtung (5) zum Neutralisieren elektrischer Ladung auf der Oberfläche der pyroelektrischen Schicht (1).
  8. Bildaufzeichnungsgerät nach Anspruch 7, wobei die Einrichtung (5) zum Neutralisieren elektrischer Ladung eine elektrische leitende Schicht (5) ist, die so ausgebildet ist, daß sie den Erwärmungsabschnitt des Thermokopfes (4) überdeckt.
  9. Bildaufzeichnungsgerät nach Anspruch 1, wobei die Entwicklungseinrichtung (7) eine Hülse (10) mit einer Magnetwalze (9) aufweist.
  10. Bildaufzeichnungsgerät nach Anspruch 1, wobei die Einrichtung (21, 21a, 21b) zum Messen der Temperatur einen Sensor (21) zum Messen der Temperatur der Heizeinrichtung (4), einen Sensor (21a) zum Messen der Umgebungstemperatur in dem Gerät und einen Sensor (21b) zum Messen der Temperatur des Ladungserhaltungsmediums (3) aufweist.
  11. Bildaufzeichnungsgerät nach Anspruch 10, wobei die Einrichtung (22) zum Steuern der Menge des Tonermediums die Menge des Tonermediums abhängig von dem Maximalwert der Temperatur der Sensoren (21, 21a, 21b) steuert.
  12. Bildaufzeichnungsgerät nach Anspruch 10, wobei die Einrichtung (22) zum Steuern der Menge des Tonermediums die Menge des Tonermediums abhängig von dem Mittelwert der Temperatur der Sensoren (21, 21a, 21b) steuert.
  13. Bildaufzeichnungsgerät nach Anspruch 10, wobei die Einrichtung (22) zum Steuern der Menge des Tonermediums eine Gleichspannungs-Energieversorgungsschaltung (206) aufweist.
  14. Bildaufzeichnungsgerät nach Anspruch 8, wobei, die Entwicklungseinrichtung (7) dem Thermokopf (4) gegenüberliegt.
EP19950304014 1994-06-13 1995-06-09 Bildaufzeichnungsgerät Expired - Lifetime EP0687963B1 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP12998794A JPH07333955A (ja) 1994-06-13 1994-06-13 画像記録装置
JP129987/94 1994-06-13
JP12998794 1994-06-13

Publications (3)

Publication Number Publication Date
EP0687963A2 EP0687963A2 (de) 1995-12-20
EP0687963A3 EP0687963A3 (de) 1997-01-08
EP0687963B1 true EP0687963B1 (de) 1999-11-03

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EP19950304014 Expired - Lifetime EP0687963B1 (de) 1994-06-13 1995-06-09 Bildaufzeichnungsgerät

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EP (1) EP0687963B1 (de)
JP (1) JPH07333955A (de)
DE (1) DE69513087T2 (de)

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01116669A (ja) * 1987-10-30 1989-05-09 Toshiba Corp 画像形成装置
JPH01314271A (ja) * 1988-06-15 1989-12-19 Oki Electric Ind Co Ltd 電子写真装置
JPH02157864A (ja) * 1988-12-12 1990-06-18 Toshiba Corp 記録装置
JPH03263057A (ja) * 1990-03-14 1991-11-22 Ricoh Co Ltd 記録方法
JP2690403B2 (ja) * 1990-02-21 1997-12-10 株式会社テック 電子写真プリント装置
JPH05531A (ja) * 1990-08-29 1993-01-08 Mita Ind Co Ltd 画像形成装置
JPH04140766A (ja) * 1990-10-01 1992-05-14 Mita Ind Co Ltd 画像形成装置
US5153615A (en) * 1991-04-26 1992-10-06 Xerox Corporation Pyroelectric direct marking method and apparatus
US5185619A (en) * 1991-04-26 1993-02-09 Xerox Corporation Electrostatic printing method and apparatus employing a pyroelectric imaging member

Also Published As

Publication number Publication date
EP0687963A2 (de) 1995-12-20
JPH07333955A (ja) 1995-12-22
DE69513087T2 (de) 2000-07-20
DE69513087D1 (de) 1999-12-09
EP0687963A3 (de) 1997-01-08

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