EP0955572B1 - Gerät zur Regulierung des Feuchtigkeitsgehaltes and der Temperatur von Medien - Google Patents

Gerät zur Regulierung des Feuchtigkeitsgehaltes and der Temperatur von Medien Download PDF

Info

Publication number
EP0955572B1
EP0955572B1 EP19980201502 EP98201502A EP0955572B1 EP 0955572 B1 EP0955572 B1 EP 0955572B1 EP 19980201502 EP19980201502 EP 19980201502 EP 98201502 A EP98201502 A EP 98201502A EP 0955572 B1 EP0955572 B1 EP 0955572B1
Authority
EP
European Patent Office
Prior art keywords
temperature
paper
web
print medium
moisture
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
EP19980201502
Other languages
English (en)
French (fr)
Other versions
EP0955572A1 (de
Inventor
Freddy Goris
Luc Hooyberghs
Luc Baeten
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.)
Xeikon Manufacturing NV
Original Assignee
Xeikon International NV
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
Application filed by Xeikon International NV filed Critical Xeikon International NV
Priority to EP19980201502 priority Critical patent/EP0955572B1/de
Priority to DE1998617324 priority patent/DE69817324T2/de
Priority to US09/297,000 priority patent/US6049680A/en
Priority to JP11125844A priority patent/JPH11338330A/ja
Publication of EP0955572A1 publication Critical patent/EP0955572A1/de
Application granted granted Critical
Publication of EP0955572B1 publication Critical patent/EP0955572B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • G03G15/14—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base
    • G03G15/16—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer
    • G03G15/1695—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer with means for preconditioning the paper base before the transfer
    • 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
    • G03G2215/00362—Apparatus for electrophotographic processes relating to the copy medium handling
    • G03G2215/00535—Stable handling of copy medium
    • G03G2215/00666—Heating or drying device

Definitions

  • the present invention relates to an apparatus for conditioning media.
  • the invention relates to conditioning a moving web of receptor material, prior to entry into an electrostatographic printer.
  • An electrostatographic printing apparatus is intended for making a large number of prints and finds use, e.g., in the field wherein classical offset printing machines are applied for making thousands of prints in a single run.
  • Electrostatographic printing operates according to the principles and embodiments of non-impact printing as described, e.g., in Principles of Non-Impact Printing by Jerome L Johnson - Palatino Press - Irvine CA, 92715 USA. Electrostatographic printing includes electrographic printing in which an electrostatic charge is deposited image-wise on a dielectric recording member. According to another technique, referred to as Direct Electrostatic Printing (DEP) as described in DE-A-4 338 992 and EP-A-0 675 417, toner particles are imagewise deposited on a substrate without the use of an electrostatic latent image.
  • DEP Direct Electrostatic Printing
  • Electrostatographic printing also includes electrophotographic printing in which an overall electrostatically charged photoconductive dielectric recording member is image-wise exposed to conductivity increasing radiation producing thereby a "direct” or “reversal” toner-developable charge pattern on said recording member.
  • the toner image is transferred onto a printing stock material, usually paper or a synthetic material such as PET (polyethyleneterephthalate) in the form of a web whereon the toner image is fixed, whereupon the web is cut into sheets containing the desired print frame.
  • the transfer of developed toner images onto paper proceeds by means of electrical corona devices to generate the required electric field to attract the charged toner from the electrostatographic recording member to the paper.
  • the transfer efficiency of toner onto the receptor paper or synthetic material is not only dictated by the contact of the paper with the toner-laden recording member and the deposited charge but also by the conductivity of the recording member and particularly by its water content.
  • the conductivity may be highly dependent on the type of receptor material, i.e. the difference of conductivity between paper and e.g. PET may be very important.
  • Paper is not a simple insulating dielectric, so the electrical properties of plain paper have some influence on toner transfer.
  • Experiments with a variety of paper types and thicknesses (i.e. weights) have established that heavier papers yield improvement in transfer efficiency.
  • Paper types with high porosity, i.e. high permeability for gases loaded with ions by corona discharge do not allow an efficient toner transfer.
  • Variation in gas permeability or porosity between different paper types is due to overall thickness, degree of filling with clays, sizings, and other paper treating substances. Apart from the paper fibres and said substances which form a constant factor for conductivity or volume resistivity there is the moisture content which fluctuates with the humidity of the environment, especially the environment of the paper storage unit containing the paper on roll.
  • That system includes a heating means, a cooling means and at least one electrometer to derive the moisture content from the electrical conductivity of the paper web and for correcting the heating means on that evaluation of the moisture content.
  • Tests have shown however that the measured electrical conductivity is not only a function of the moisture content alone.
  • the heating means may further influence or increase the temperature of the moving paper web in an attempt to lower the moisture content, whereas that moisture content already reached an optimum value. This shows that a problem remains to be solved.
  • Even if other types of sensors are used to assess the moisture content of the media, such as humidity sensors or direct contact resistor sensors, other parameters still influence the relation between the measured value and the absolute moisture content.
  • the media may take the form of a web but the media may as well comprise sheet-like material, such as A4 or A3-sized pages of paper.
  • the media is moving relative to the heating means and/or cooling means, i.e. some elements may be stationary, some may be moving.
  • the media may comprise paper, preferably with grammages of 40, 80, 100 or 350 g/m 2 , or any value within the range of 40-350 g/m 2 .
  • a paper receptor material may consist of paper or may comprise, for example, paper containing synthetic fibres or paper coated on at least one side with a non-paper material, for example, with a synthetic polymeric material.
  • the media may also mainly consist of a synthetic material such as PET having preferably a thickness between 12 and 350 ⁇ m.
  • the media may be labels including an adhesive layer or may mainly consist of PVC (polyvinylchloride) or PE (polyethylene). All these media may absorb or adsorb a variable amount of moisture, either during production or during contact with the ambient atmosphere.
  • the apparatus and method according to the current invention may also be used during the production process of these media.
  • the media produced have a constant moisture content as they are wound on a roll of web material or packed in a stack of sheets. By making use of the current invention, the moisture condition and the temperature condition may be kept within narrow limits.
  • the sensor of the moisture content may be realised by a sensor of for measuring the relative humidity.
  • the moisture content may also be assessed by indirect measurement, i.e. by measuring another parameter, related to the moisture content.
  • the conductivity of the media after the heating and cooling steps is measured.
  • the conductivity of the media may be measured by positioning the media between two electrical conductors, both making contact to the media, closely to each other. One conductor may be placed on the front side of the media, the other one on the back side. Alternatively, both conductor may be placed closely adjacent to each other, without making direct contact with each other but both contacting the media.
  • the media may be a moving paper receptor material suitable for use in an electrostatographic printer.
  • the heating means has as most important function to reduce the moisture content of the receptor material or media.
  • the heating means is enclosed in a heating cabinet having a receptor material entrance, a receptor material exit, means for the entrance of fresh air and exhaust means for expelling moist air produced by heating the receptor material.
  • a cooling cabinet may be provided comprising means for cooling the heated receptor material with dry air to bring its temperature within the range of 15° C to 40° C before leaving the apparatus.
  • the cooling cabinet may also have the capability to further increase the temperature of the media, e.g. the receptor material, in order to achieve a predetermined temperature.
  • the heating cabinet is connected to a cooling cabinet.
  • the conditioning apparatus further comprises control means for controlling said heating means, and optionally said cooling means, in response to the electrical condition of the receptor material sensed by said sensing means.
  • control means for controlling said heating means, and optionally said cooling means, in response to the electrical condition of the receptor material sensed by said sensing means.
  • the output from the sensing means may be fed to a visual indicator from which the operator may check the condition of the receptor material and make adjustments to the moisture control means to bring the electrical condition of the receptor material within a desired range.
  • the heating means may comprise a heated rotatable drum or cylinder in contact with at least one side of said receptor material as it moves along said receptor material path.
  • the heating means may comprise a radiant-heat dryer having at least one radiant-heat source positioned to project infrared radiation onto at least one side of the receptor material as it moves along the receptor material path.
  • the radiant-heat dryer has a dominant energy output wavelength within the range of from 1.5 ⁇ m to 10 ⁇ m.
  • the moisture control means may comprise at least one nozzle positioned to direct a stream of hot air onto at least one side of the receptor material as it moves along the receptor material path.
  • the heating means may even be a dielectric dryer containing at least one radio-frequency or microwave source positioned such that the receptor material moves through the electromagnetic field of the source as it moves along the receptor material path.
  • the temperature to which the receptor material is heated by the heating means is preferably at least 120° C, such as about 140° C or 180° C. Too high a temperature may lead to damage being caused to the receptor material.
  • the receptor material is conditioned to a moisture content of from 1 to 2% by weight, preferably up to 1.5%. We prefer that the moisture content does not fall below 0.5%, since receptor material which is too dry might result in high triboelectric charges to be generated thereon, the discharge of which in the printer may have undesirable effects.
  • the moisture sensing means may comprise a corona discharge device positioned adjacent the receptor material path to build up a predetermined electrostatic charge on at least one side of the receptor material and, in a first embodiment, means positioned downstream of the corona discharge device for sensing the level of electrostatic charge retained on the receptor material.
  • the supply current fed to the corona discharge device is preferably within the range of 1 to 10 ⁇ A/cm, most preferably from 2 to 5 ⁇ A/cm, depending upon the receptor material characteristics and will be positioned at a distance of from 3 mm to 10 mm from the path of the receptor material.
  • means are positioned downstream of the corona discharge device for sensing the decay of electrostatic charge on said receptor material.
  • the means for sensing the decay of electrostatic charge on said receptor material may comprise a plurality of spaced electrometers positioned adjacent said receptor material path and means for comparing output signals from said electrometers.
  • a receptor material charge discharging device such as an AC corona device, is positioned downstream of the charge sensing means for discharging the static charge on the receptor material before it leaves the apparatus.
  • the receptor material conditioning apparatus is coupled to an electrostatographic printer for forming an image onto a receptor material.
  • the printer may comprise at least one toner image-producing electrostatographic station having rotatable endless surface means onto which a toner image can be formed, means for conveying the receptor material past the stations and means for transferring the toner image on the rotatable surface means onto the receptor material.
  • the humidity of the atmosphere inside said electrostatographic printer is controlled. This is done with the aim of maintaining the electrical condition of the receptor material within a desired range.
  • the receptor material is in the form of a web, for example supplied from a roll, but the invention is equally applicable to receptor material in the form of separate sheets.
  • a printer 10 having a supply station 13 in which a roll 14 of web material 12 is housed in sufficient quantity to print, say, 3 to 5,000 images.
  • the web 12 is conveyed from the supply station 13, through the paper conditioning apparatus 11 into a tower-like printer housing 44 in which a support column 46 is provided, housing four similar printing stations A to D which are arranged to print yellow, magenta, cyan and black images.
  • a further station E is provided in order to optionally print an additional colour, for example a specially customised colour.
  • the web of paper 12 is conveyed in an upwards direction past the printing stations in turn.
  • the printing stations A to E are mounted in a substantially vertical configuration resulting in a reduced footprint of the printer and additionally making servicing easier.
  • the column 46 may be mounted against vibrations by means of a platform 48 resting on springs 50, 51.
  • the image on the web is fixed by means of the image-fixing station 16 and fed to a cutting station 20 (schematically represented) and a stacker 52 if desired.
  • the web 12 is conveyed through the printer by two drive rollers 22a, 22b one positioned between the conditioning station 11 and the first printing station A and the second positioned between the image-fixing station 16 and the cutting station 20.
  • the drive rollers 22a, 22b are driven by controllable motors, 23a, 23b.
  • each printing station comprises a cylindrical drum 24 having a photoconductive outer surface 26. Circumferentially arranged around the drum 24 there is a charging device 28 capable of uniformly charging the drum surface, an exposure station 30 which will image-wise and line-wise expose the photoconductive drum surface causing the charge on the latter to be selectively dissipated, leaving an image-wise distribution of electric charge to remain on the drum surface.
  • This so-called "latent image” is rendered visible by a developing station 32 which brings a toner developer in contact with the drum surface 26.
  • the toner particles are attracted to the latent image on the drum surface by the electric field between the drum surface and the developer so that the latent image becomes visible.
  • the toner image adhering to the drum surface 26 is transferred to the moving web 12 by a transfer corona device 34.
  • the moving web 12 is in face-to-face contact with the drum surface 26 over a wrapping angle ⁇ of about 15° determined by the position of guide rollers 36.
  • the transfer corona device being on the opposite side of the web to the drum, and having a high potential opposite in sign to that of the charge on the toner particles, attracts the toner particles away from the drum surface 26 and onto the surface of the web 12.
  • the transfer corona device typically has its corona wire positioned about 7 mm from the housing which surrounds it and 7 mm from the paper web.
  • a typical transfer corona current is about ⁇ 3 ⁇ A/cm.
  • the transfer corona device 34 also serves to generate a strong adherent force between the web 12 and the drum surface 26, causing the latter to be rotated in synchronism with the movement of the web 12. Circumferentially beyond the transfer corona device 34 there is positioned a web discharge corona device 38 driven by alternating current.
  • the drum surface 26 is pre-charged by a corona 40, causing any residual toner which might still cling to its surface to become loosened so that it may be collected at a cleaning unit 42 known in the art.
  • the cleaning unit 42 includes a rotating cleaning brush 43. After cleaning, the drum surface is ready for another recording cycle.
  • the web After passing the first printing station A, as described above, the web passes successively to printing stations B, C, D and E, where images in other colours are transferred to the web. It is critical that the images produced in successive stations be in register with each other. In order to achieve this, the start of the imaging process at each station has to be critically timed.
  • the paper web 12 is unwound from a supply roll 14 and led through an entrance slit 53 into a heating cabinet 54 wherein the paper web 12 follows a curved path defined by a plurality of rollers 100. Between the first and second of said rollers 100, the paper web is in contact with a metal heating drum 55, having a tubular infrared heating source 56 inside.
  • the heating drum may mainly consist of aluminium or copper.
  • the temperature of the heating drum 55 is sensed by a temperature sensor 85. The signal of this temperature sensor 85 may be fed to an electronic control device 101 to control the output of the infrared heating source 56, especially when the apparatus is in a standby status, i.e. when no paper transport takes place.
  • a fan 57 mounted in a wall of the cabinet 54 expels moist air out of the cabinet 54 while ambient air enters through the inlet slits 58.
  • the heated paper web 12 passes through a slot 59 into a cooling cabinet 60, wherein by means of ventilators 61 and 62 cold dry air is circulated along both sides of the paper web 12, as indicated by the arrows 63 and 64.
  • the cooling box 65 has a tight entrance slit 66 closed by a felt brush and contains heat-exchangers 67 and 68 in which circulating cold water (at a temperature of for example 1° to 7° C) is passed, through cold water inlets 69 and outlets 70.
  • a reservoir (not shown) is connected to the drain holes 77 of the cooling box 65 to collect condensed water which is then led to a drain.
  • the paper web 12 leaves the cooling box 65 via a tight exit slit 71 and enters a housing 78 containing a sensing means.
  • the paper web 12 follows a curved path into contact with an earthed metal drum 72.
  • This drum may mainly consists of iron or steel.
  • the drum 72 is kept at a temperature equal to that of the paper web after cooling. This may be achieved by a lamp (not shown) or by cooling, irradiating the drum 72 where it is not covered by the web 12.
  • the paper web 12 then follows the surface of the drum 72, closely adjacent a DC corona discharge unit 73, also referred to as transfer corona. This unit 73 sprays electrical charge on the paper web 12, from which the paper thus receives a predetermined corona charge.
  • the paper web 12 then passes an electrometer head 74, also referred to as (contactless) electrostatic voltage sensor, downstream of the corona discharge unit 73, which measures the remaining charge level as a voltage which is related to the electrical condition of the paper.
  • the signal from the electrometer head 74 passes via a line 102 to the electronic control device 101.
  • the control device 101 processes said signal in accordance with a previous calibration of the apparatus and controls the supply of electrical power via line 103 to the heating source 56 to automatically adjust the heat energy supply in accordance with the remaining charge level sensed by the electrometer 74 to bring the condition of the paper within the desired range.
  • the electrometer should typically detect a charge height of at least 500 V.
  • the operation of the electronic moisture control device may be explained as follows. The electrostatic voltage measured by the electrometer 74 will we be lower than the electrostatic voltage generated on the web materiel at the location of the corona discharge unit 73.
  • the amount of charge leaking away is a function of the time that the web material is in contact with the drum. This time is inversely proportional to the angular velocity of the drum 72 and proportional to the distance between the corona discharge unit 73 and the electrometer head 74.
  • the amount of charge leaking away is also a function of the conductivity of the web material. If the web material has a high conductivity, then the amount of dissipated charge will be high ; a low conductivity will cause a low amount of electrical charge to leak away to the earthed metal drum 72.
  • the conductivity or more precisely, the amount of charge leaking away per unit of time, is not only a function of the moisture content of the cooled web material, but also a function of the temperature of the cooled web material. It has been found that the conductivity raises with raising temperature, even if the moisture content is kept constant. This causes the following problem in prior art systems. If the temperature of the cooled web material is higher than the reference temperature, e.g. 25° C, then the electrometer 74 will detect a voltage e.g. lower than 360 V, which is considered as being due to a high leakage of charge.
  • the electronic moisture control device 101 may interpret this high leakage as a high moisture content of the web material and accordingly increase the radiant output of the infrared heating source 56 to increase the temperature of the heating drum 55. Since the heated media gets warmer by this extra energy, the media after cooling in the cooling box 65 will also get a higher temperature, e.g. 31° C. This higher temperature of the cooled web material dramatically increases the conductivity measured by the electrometer 74, although the moisture content may have decreased due to the higher temperature of the heated web material in the heating cabinet 54. Therefore, the electronic moisture control device 101 may command an even higher radiant power for the infrared heating source in an attempt to lower the conductivity of the web material 12. It is clear that this system drifts away from its optimal and preferably stable working point.
  • a temperature sensor 81 is located close to the cooled web material, preferably after it left the cooling box 65. In a more preferred embodiment, the temperature sensor 81 is located close to the periphery of the drum 72, where the web material 12 is in contact with the drum.
  • the signal generated by the temperature sensor 81 is transmitted via a temperature sensor line 82 to an electronic temperature control device 83.
  • This control device 83 transmits a signal via a signal line 84 to the cooling box 65 to increase or decrease the cooling power of the cooling box 65.
  • the temperature control device 83 operates in such a manner that the temperature sensed by the sensor 81 is constant or situated within a narrow temperature range of 2° C or less. If the control device 83 gets a temperature signal indicative of a temperature higher than the predetermined range, then the control device 83 instructs the cooling box to increase the cooling power. If the temperature of the cooled web material is too low, then the cooling power of the cooling box 65 is decreased, such that the web material leaving exit slit 71 gets a higher temperature.
  • the temperature of the web material leaving the cooling box 65 is kept substantially constant. This has two advantages. first of all, the conductivity or electrostatic charge leakage is more closely related to the moisture content of the heated and subsequently cooled media. On the other hand, the temperature of the media leaving the housing 78 is substantially constant, such that other process parameters, which may by highly dependent on the temperature of the media, can be controlled independently from the temperature. As explained before, the length and width of the media may be influenced by the temperature.
  • the cooling box will produce frigories (i.e. 'cold calories') for cooling the web material. In this process, calories are inevitably generated partly due to the cooling process, partly due to the mechanical and electrical energy losses.
  • the calories generated by the cooling box 65 may be recuperated by the heating process. This may be done for example by use of a Peltier module such as described in US-A- 4,519,389 or EP-A- 0 651 308.
  • the cold side or junction of the Peltier module may produce the frigories for the cooling box 65, the hot junction may produce the calories for the heating means 55, or an air flow cooling the hot junction may be guided to the inlet slits 58 of the heating cabinet 54. This way heat energy dissipated or withdrawn from the cooling means 65 may be transported to the heating means 55 and heat energy may be recuperated.
  • An AC discharge corona 75 also referred to as erase corona, positioned downstream of the electrometer head 74 brings the paper web back to its ground state before it leaves the housing 78 through the exit slot 76. This measure is taken to avoid that the web material 12 sticks to the drum 72 at the point where the material has to leave the drum.
  • the paper web passes from the exit slot 76 directly into the printer shown in Figure 1.
  • the web drive for the printer serves to drive the paper web 12 from its supply roll 14 through the conditioning apparatus, the paper web being maintained in a tensioned state by the brake 15 acting on the roll 14.
  • the output signal from the electrometer head 74 and from the temperature sensor 81 may alternatively or additionally be fed to a visual indicator from which the operator may check the condition of the paper web.
  • two spaced electrometer heads 74a and 74b also referred to as (contactless) electrostatic voltage sensors, are positioned adjacent the paper web path downstream of the corona discharge unit 73.
  • the temperature sensor 81 gives feedback about the temperature of the moving paper web 12. That information is used to control the cooling power of the cooling box 65, such that the temperature of the paper in the. housing 78 is kept within a narrow temperature range.
  • the control device (not shown in Figure 4) compares the signals received from the two electrometers 74a and 74b to determine the rate of decay of electrostatic charge on the paper web. This rate of decay, being indicative of the electrical condition of the paper web, is then used to automatically adjust the heat energy supply in accordance with the rate of charge decay sensed by the electrometer heads 74a, 74b to bring the condition of the paper within the desired range.
  • the embodiment shown in Figure 4 has the advantage over that shown in Figure 3, of not requiring previous calibration.
  • the voltage or the electrical current of the corona discharge unit 73 may be controlled by the output signal of the first electrometer 74a, in such a way that the electrostatic voltage sensed by the electrometer 74a has a predetermined constant level of e.g. 500 V.
  • either the output signal of the second electrometer 74b alone or a difference signal from both electrometers 74a and 74b may be sent to the electronic moisture control device 101.
  • the temperature sensor 81 is preferably located between the first electrometer 74a and the second electrometer 74b. Alternatively, the temperature sensor 81 may be located at any location close to where the web material 12 is in contact with the drum 72.
  • the output signal from the temperature sensor 81 may control other portions of the printer 10. Parameters such as cut length, transfer current in transfer corona device 34 and image scales may be varied as a function of the temperature measured by sensor 81. In such case, the temperature may vary for example between 24° C and 26° C or higher, without correcting the cooling power of the cooling box 65.
  • the temperature signal 82 may then be fed (not shown) to the electronic moisture control device 101 in order to correct the moisture signal 102 for the higher or lower temperature.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Control Or Security For Electrophotography (AREA)
  • Paper Feeding For Electrophotography (AREA)

Claims (8)

  1. Konditionierungsvorrichtung zum Konditionieren des Feuchtigkeitsgehalts eines Druckmediums (12) vor der Einführung in einen elektrographischen Drucker welche aufweist:
    einem Erwärmungsmittel (55) zum Erwärmen des Druckmediums,
    einem Kühlungsmittel (65) zum Kühlen des erwärmten Druckmediums,
    einem Feuchtigkeitssensor (74) zum Erfassen des Feuchtigkeitsgehalts des gekühlten Druckmediums, wodurch ein Feuchtigkeitssignal (102) erzeugt wird,
    einem ersten Steuermittel (101) zum Steuern des Erwärmungsmittels (55) als Reaktion auf das Feuchtigkeitssignal (102),
    dadurch gekennzeichnet, dass die Konditionierungsvorrichtung außerdem aufweist :
    einen Temperatursensor (81) zum Erfassen der Temperatur des gekühlten Druckmediums, wodurch ein Temperatursignal (82) erzeugt wird,
    zweite Steuermittel (83) zum Steuern der Temperatur des Druckmediums (12) beim Verlassen der Konditionierungsvorrichtung als Reaktion auf das Temperatursignal (82).
  2. Konditionierungsvorrichtung nach Anspruch 1, wobei das zweite Steuermittel (83) zum Steuern des Kühlungsmittels (65) als Reaktion auf das Temperatursignal (82) dient.
  3. Konditionierungsvorrichtung nach einem der vorhergehenden Ansprüche, wobei der Feuchtigkeitssensor (74) einen Leitfähigkeitssensor zum Erfassen der Leitfähigkeit des Druckmediums aufweist.
  4. Konditionierungsvorrichtung nach einem der vorhergehenden Ansprüche, wobei der Leitfähigkeitssensor aufweist:
    einen Ladungsgenerator (73) zum Erzeugen einer elektrostatischen Ladung auf dem gekühlten Druckmedium,
    einen Ladungsdetektor (74) zum Erzeugen des Feuchtigkeitssignals (102).
  5. Konditionierungsvorrichtung nach einem der vorhergehenden Ansprüche, wobei der Leitfähigkeitssensor außerdem einen zweiten Ladungsdetektor (74b) zum Kalibrieren des Feuchtigkeitssignals (102) aufweist.
  6. Konditionierungsvorrichtung nach einem der vorhergehenden Ansprüche, wobei das Druckmedium (12) die Form einer Bahn hat.
  7. Verfahren zum Konditionieren des Feuchtigkeitsgehalts eines Druckmediums (12) in einer Konditionierungsvorrichtung vor der Einführung in einen elektrographischen Drucker welches folgenden Schritten aufweist:
    Erwärmen des Druckmediums (12) durch Erwärmungsmittel (55),
    Kühlen des erwärmten Druckmediums durch Kühlungsmittel (65),
    Erfassen des Feuchtigkeitsgehalts des gekühlten Druckmediums, wodurch ein Feuchtigkeitssignal (102) erzeugt wird,
    Steuern des Erwärmungsmittels (55) als Reaktion auf das Feuchtigkeitssignal (102),
    dadurch gekennzeichnet, dass das Verfahren außerdem die folgende Schritte aufweist:
    Erfassen der Temperatur des gekühlten Druckmediums, wodurch ein Temperatursignal (82) erzeugt wird,
    Steuern der Temperatur des Mediums (12) beim Verlassen der Konditionierungsvorrichtung als Reaktion auf das Temperatursignal (82).
  8. Verfahren nach einem der vorhergehenden Ansprüche, welches den Schritt des Steuerns des Kühlungsmittels (65) als Reaktion auf das Temperatursignal (82)aufweist.
EP19980201502 1998-05-08 1998-05-08 Gerät zur Regulierung des Feuchtigkeitsgehaltes and der Temperatur von Medien Expired - Lifetime EP0955572B1 (de)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP19980201502 EP0955572B1 (de) 1998-05-08 1998-05-08 Gerät zur Regulierung des Feuchtigkeitsgehaltes and der Temperatur von Medien
DE1998617324 DE69817324T2 (de) 1998-05-08 1998-05-08 Gerät zur Regulierung des Feuchtigkeitsgehaltes and der Temperatur von Medien
US09/297,000 US6049680A (en) 1998-05-08 1999-04-22 Apparatus for conditioning moisture content temperature of media
JP11125844A JPH11338330A (ja) 1998-05-08 1999-05-06 メデイアの湿気含有量と温度とを調節する器械

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP19980201502 EP0955572B1 (de) 1998-05-08 1998-05-08 Gerät zur Regulierung des Feuchtigkeitsgehaltes and der Temperatur von Medien

Publications (2)

Publication Number Publication Date
EP0955572A1 EP0955572A1 (de) 1999-11-10
EP0955572B1 true EP0955572B1 (de) 2003-08-20

Family

ID=8233695

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19980201502 Expired - Lifetime EP0955572B1 (de) 1998-05-08 1998-05-08 Gerät zur Regulierung des Feuchtigkeitsgehaltes and der Temperatur von Medien

Country Status (3)

Country Link
EP (1) EP0955572B1 (de)
JP (1) JPH11338330A (de)
DE (1) DE69817324T2 (de)

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5913260A (ja) * 1982-07-15 1984-01-24 Fuji Xerox Co Ltd 複写機の用紙防湿装置
JPS59104667A (ja) * 1982-12-08 1984-06-16 Canon Inc 転写制御方法
EP0629925B1 (de) * 1993-06-18 1996-09-04 Xeikon Nv Vorbehandlungsgerät für Empfängermaterial
JP3161186B2 (ja) * 1993-10-21 2001-04-25 富士ゼロックス株式会社 画像形成装置の用紙除湿装置

Also Published As

Publication number Publication date
DE69817324T2 (de) 2004-06-09
JPH11338330A (ja) 1999-12-10
EP0955572A1 (de) 1999-11-10
DE69817324D1 (de) 2003-09-25

Similar Documents

Publication Publication Date Title
US6049680A (en) Apparatus for conditioning moisture content temperature of media
EP0629931B1 (de) Elektrostatografischer Drucker zum Erzeugen eines Bildes auf einem Empfangselement
US6047156A (en) Single-pass, multi-color electrostatographic duplex printer
US5264899A (en) Sheet moisture replacement system using porous rolls
US6075965A (en) Method and apparatus using an endless web for facilitating transfer of a marking particle image from an intermediate image transfer member to a receiver member
US4912515A (en) Image forming apparatus
US5539498A (en) Paper receptor material conditioning apparatus and method
EP1102129B1 (de) Kontrolle der Übertragungsspannung in einem Farbbilderzeugungsgerät
EP0871082B1 (de) Elektrostatographisches Druckgerät und Verfahren
US20070071475A1 (en) Method of controlling throughput of media in a printer
US5850589A (en) Sheet moisture replacement system using water jet technology
JP2002251043A (ja) 自動センサーを用いたハードコピー装置の制御方法および装置
JPH06242701A (ja) 定着装置
EP0905574B1 (de) Feuchtigkeitskontrolle zur Beseitigung von Blattwellungen
JP2010256938A (ja) 画像再生装置における転写後画像調整方法及び装置
EP0629925B1 (de) Vorbehandlungsgerät für Empfängermaterial
US5585908A (en) Image forming apparatus usable with variable width receivers
EP0775948A1 (de) Mehrfarben elektrostatographischer Drucker mit einem Umlauf
EP0955572B1 (de) Gerät zur Regulierung des Feuchtigkeitsgehaltes and der Temperatur von Medien
US20100266317A1 (en) Image forming apparatus and image forming method
US7796907B2 (en) Method and apparatus for detecting and avoiding a defect on a fuser web
JPH11161109A (ja) コンディショナロール上の水膜の厚さ検知装置
AU711725B2 (en) An electrostatographic printer
US5568228A (en) Image forming apparatus with controlled transfer
CA2191037A1 (en) Single pass, multi-colour electrostatographic printer

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): BE DE FR GB

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17P Request for examination filed

Effective date: 20000510

AKX Designation fees paid

Free format text: BE DE FR GB

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: XEIKON NV

17Q First examination report despatched

Effective date: 20020628

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: XEIKON INTERNATIONAL N.V.

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): BE DE FR GB

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: BE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20030820

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REF Corresponds to:

Ref document number: 69817324

Country of ref document: DE

Date of ref document: 20030925

Kind code of ref document: P

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20040524

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20140527

Year of fee payment: 17

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20160129

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20150601

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20160520

Year of fee payment: 19

Ref country code: DE

Payment date: 20160520

Year of fee payment: 19

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 69817324

Country of ref document: DE

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20170508

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20171201

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170508