EP1080942B1 - Méthode de régénération d'une plaque d'impression lithographique - Google Patents

Méthode de régénération d'une plaque d'impression lithographique Download PDF

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Publication number
EP1080942B1
EP1080942B1 EP99202799A EP99202799A EP1080942B1 EP 1080942 B1 EP1080942 B1 EP 1080942B1 EP 99202799 A EP99202799 A EP 99202799A EP 99202799 A EP99202799 A EP 99202799A EP 1080942 B1 EP1080942 B1 EP 1080942B1
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EP
European Patent Office
Prior art keywords
printing
support
recording layer
press
master
Prior art date
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EP99202799A
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German (de)
English (en)
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EP1080942B2 (fr
EP1080942A1 (fr
Inventor
Augustin c/o Agfa-Gevaert N.V. Meisters
Joan C/O Agfa-Gevaert N.V. Vermeersch
Luc C/O Agfa-Gevaert N.V. Leenders
Bavo c/o Agfa-Gevaert N.V. Muys
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Agfa NV
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Agfa Gevaert NV
Agfa Gevaert AG
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Application filed by Agfa Gevaert NV, Agfa Gevaert AG filed Critical Agfa Gevaert NV
Priority to EP99202799A priority Critical patent/EP1080942B2/fr
Priority to DE69913518T priority patent/DE69913518T2/de
Priority to US09/638,877 priority patent/US6408755B1/en
Priority to JP2000258756A priority patent/JP2001105763A/ja
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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41N—PRINTING PLATES OR FOILS; MATERIALS FOR SURFACES USED IN PRINTING MACHINES FOR PRINTING, INKING, DAMPING, OR THE LIKE; PREPARING SUCH SURFACES FOR USE AND CONSERVING THEM
    • B41N3/00—Preparing for use and conserving printing surfaces
    • B41N3/006—Cleaning, washing, rinsing or reclaiming of printing formes other than intaglio formes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41C—PROCESSES FOR THE MANUFACTURE OR REPRODUCTION OF PRINTING SURFACES
    • B41C1/00—Forme preparation
    • B41C1/10—Forme preparation for lithographic printing; Master sheets for transferring a lithographic image to the forme

Definitions

  • the present invention relates to a method for erasing the image of a lithographic printing master by treating the printing surface with an atmospheric plasma.
  • Printing presses use a so-called master such as a printing plate which is mounted on a cylinder of the printing press.
  • the master carries an image which is defined by the ink accepting areas of the printing surface and a print is obtained by applying ink to said surface and then transferring the ink from the master onto a substrate, which is typically a paper substrate.
  • ink as well as an aqueous fountain solution are fed to the printing surface of the master, which consists of oleophilic (i.e. ink accepting) and hydrophilic (water accepting) areas.
  • driographic printing only ink is applied to the printing surface, which consists of ink accepting and ink repelling areas. These ink-repelling areas are often called oleophobic or ink-abhesive areas.
  • Driographic plates are sometimes simply called 'dry' plates as distinct from the conventional 'wet' plates.
  • Printing masters are generally obtained by the so-called computer-to-film method wherein various pre-press steps such as typeface selection, scanning, colour separation, screening, trapping, layout and imposition are accomplished digitally and each colour selection is transferred to graphic arts film using an image-setter.
  • the film can be used as a mask for the exposure of an imaging material called plate precursor and after plate processing, a printing plate is obtained which can be used as a master.
  • a printing master which comprises a metal support characterised by a good dimensional stability, e.g. a printing plate comprising an aluminium support. Since the metal support is an expensive component of the printing master, it would be advantageous to provide a method for removing the printing surface from the support so that it can be reused for making another printing master. Also in on-press coating methods it is necessary to remove the coating from the cylinder by a cleaning step. Such a cleaning step is preferably carried out on-press by a fast, environment-friendly and simple operation which enables easy automatisation, thereby obtaining a more efficient workflow which is characterised by improved convenience and a short press down-time between printing jobs.
  • EP-A 594 097 describes the use of solvents for removing the printing layers from a metal support. Solvents however are secondary wastes which need to be collected during the cleaning step and then disposed off.
  • EP-A 570 879 describes a method using a jet of pressurised water for erasing a lithographic printing master obtained by image-wise thermal transfer of an ink accepting layer.
  • the use of water is to be avoided as it may cause corrosion of the metal parts of the printing press.
  • This object is realised by the method defined in claim 3.
  • Figure 1 shows a schematic representation of a section of an atmospheric plasma jet generator for use in the methods of the present invention.
  • the image of a lithographic printing master is erased by treating the printing surface thereof with a glow discharge plasma that is capable of operating at one atmosphere of pressure, hereinafter referred to as "atmospheric plasma".
  • the atmospheric plasma is capable of converting ink accepting areas of the printing master to hydrophilic areas, thereby erasing the lithographic image of the printing master.
  • EP-A 821273 describes atmospheric plasma treatment of a polyester support for improving the adherence of coated layers.
  • WO 96/38311 describes cleaning methods using atmospheric plasma treatment, wherein the substrate to be cleaned is used as an electrode for generating the glow discharge. None of these prior art documents, however, describes a method for erasing the image from a printing surface of a lithographic printing master.
  • an atmospheric plasma jet is used for erasing the printing master.
  • a concentrated plasma jet is generated through an arc discharge between two electrodes while feeding a working gas. The electric arc is not transferred to the surface of the material that is exposed to the plasma jet.
  • Such a method allows to treat a material without using it as an electrode for generating the plasma, i.e. also non-conducting surfaces can be cleaned by a plasma jet.
  • a preferred embodiment of an atmospheric plasma jet generator for use in the present invention comprises a nozzle of which a section is shown in Figure 1.
  • the nozzle comprises a nozzle pipe 2 of which the internal diameter acts as a flow channel for working gas which is driven (indicated by the arrows in Figure 1) into a plasma chamber 7 through perforations 4 in wall 5.
  • a glow discharge is sustained in the plasma chamber 7 by a voltage between the inner pin electrode 3 and outer ring electrode 6.
  • the working gas which enters the plasma chamber 7 continuously expels the plasma out of the nozzle towards the surface 1. Simultaneously, the gas also acts as a cooling medium. More details of a suitable atmospheric plasma jet generator are described in US 5,837,958.
  • the voltage for driving the plasma generator is preferably a highfrequency alternating voltage in the range of 10 to 30 kV as described in German Patentschrift DE 42 35 766 C1.
  • the plasma may be formed in air at about one atmosphere of pressure.
  • the plasma may also be formed at pressures below or above atmospheric pressure, if desired.
  • Working gases other than air may also be used, e.g. the noble gases such as helium, neon or argon as well as oxygen, nitrogen, nitrous oxide, carbon dioxide or mixtures thereof.
  • the plasma jet is preferably directed towards the printing surface of the lithographic printing master while scanning the plasma jet over said surface.
  • Such scanwise treatment is preferably carried out while the printing master is mounted on a cylinder.
  • one or more nozzles may be translated along a path parallel to the axis of the cylinder, while rotating said cylinder, so as to treat the whole surface of the printing master.
  • the latter method is especially suitable for cleaning while the printing master is mounted on rotary printing presses.
  • Other methods are also possible, e.g. a so-called flat-bed configuration wherein the surface of the printing master is essentially planar and the plasma jet is scanned over said surface in one direction while moving the printing master in another direction, perpendicular to the former.
  • the methods of the present invention can be used in computer-to-plate (off-press exposure) or computer-to-press (on-press exposure) procedures.
  • means for erasing the printing master such as the nozzle described above are integrated in the printing press.
  • said means may be integrated in a dedicated cleaning apparatus nearby the printing press.
  • the cleaning apparatus may be mechanically coupled to the printing press so that the printing master can be transferred automatically between the printing press and the cleaning apparatus.
  • the cleaning method described above allows to make fully automatic printing presses wherein all the following steps are performed on-press : (i) making an imaging material (the printing master precursor) by providing a support with an image recording layer; (ii) making a printing master by image-wise exposing and optionally developing the imaging material; (iii) starting a pressrun; and (iv) cleaning the printing master using an atmospheric plasma as described above. After cleaning, the support can again be provided with an image recording layer and after exposure and optional development, a next print job can be started.
  • the support used in the present invention can be e.g. a (plate) cylinder of a rotary printing press, a sheet, a plate, a sleeve or a belt.
  • the support may be mounted on a cylinder of a printing press while being provided with a recording layer, or while being exposed, processed or cleaned according to the present invention.
  • the support can be a plastic support but is preferably a metal plate, e.g. polished stainless steel or, more preferably, aluminium.
  • Phosphor bronze an alloy comprising >90 wt.% of copper, ⁇ 10 wt.% of tin and small amounts of phosphor
  • the support can also be a composite material, e.g. a material comprising carbon fibre.
  • the support When used for wet lithographic printing, the support is preferably hydrophilic or provided with an hydrophilic coating, e.g. grained and anodised aluminium.
  • the support When used for dry lithographic printing, the support is preferably ink-abhesive or provided with an ink-abhesive coating, e.g. a silicone or a fluoropolymer coating.
  • the wording 'providing a support with an image recording layer' as used herein also includes embodiments wherein said recording layer is provided on top of another layer which is carried by said support, e.g. the hydrophilic or ink-abhesive layer mentioned above.
  • the recording layer may be image-wise exposed by applying heat or light to the layer.
  • Light exposure includes exposure to light in heat-mode and in photo-mode, i.e. the imaging mechanism can be triggered directly by the energy of the photons or indirectly by the heat generated upon light absorption.
  • Highly preferred image recording compositions for use in the method of the present invention have been disclosed in European Patent Application (EP-A) Nos. EP-A-974 455 and EP-A-972 637, both filed on the 16th of July, 1998, and EP-A-993 945, filed on the 15th of October, 1998.
  • EP-A-993 945 filed on the 15th of October, 1998.
  • the teaching of these copending and co-owned applications is repeated below in a summarised form.
  • the problem of cleaning the support after the pressrun was left unsolved by the co-owned EP-As cited above, because the printing surface of the imaging materials described therein cannot easily be erased by the known cleaning liquids.
  • the imaging materials which have been described in the co-owned EP-As referred to above, are negative-working materials which comprise a light absorbing compound and may further comprise so-called reactive compounds and non-reactive compounds, each of which will be discussed hereafter. These compounds may be present in a stack of layers provided on the support but a single layer is preferred.
  • the light absorbing compound may be present in all the layers of said stack or may be localised in just a single layer of said stack, said single layer being the recording layer of the material. In a material according to the latter embodiment the recording layer is preferably applied directly on the support.
  • the imaging materials which have been described in the co-owned EP-As referred to above, comprise a light absorbing compound as main compound, i.e. present in an amount not less than 50% relative to all the compounds present in the layer(s) that are provided on the support.
  • the amount of light absorbing compound is not less than 70% by weight and even more preferably not less than 90% by weight relative to the layer(s) of the imaging material, excluding the support.
  • the recording layer consists essentially of a light absorbing compound.
  • Mixtures of light absorbing compounds can also be used, and then, the total amount of all light absorbing compounds relative to all the compounds in the imaging material excluding the support is not less than 50% by weight, preferably not less than 70% by weight and even more preferably not less than 90 % by weight.
  • Useful light absorbing compounds for use in the present invention are for example organic dyes, carbon black, metal carbides, borides, nitrides, carbonitrides, or oxides.
  • the imaging materials used in the present invention are preferably heat-mode materials which are sensitive to near infrared light. Accordingly, the light absorbing compound is preferably a near infrared light absorbing compound.
  • Carbon, graphite, soot and the infrared dyes of which the structural formulae are listed in the co-owned EP-As cited above are preferred. It is also possible to use polymers such as a polypyrrole, polyethylenedioxithiophene or polyaniline-based polymer.
  • the recording layer is preferably characterised by a very thin layer thickness, i.e. a dry layer thickness below 1 ⁇ m, preferably below 0.5 ⁇ m and even more preferably ranging from 0.25 to 0.1 ⁇ m.
  • a layer thickness below 0.1 ⁇ m may still give satisfactory results. For instance, it was observed that an anodised aluminium support which is provided with a 0.1 ⁇ m graphite layer, then wiped thoroughly with a dry cloth and then image-wise exposed in heat-mode, still provides an excellent printing master.
  • the heat-mode materials known prior to the above co-owned EP-As generally comprise a light absorbing compound in a typical amount relative to all the compounds in the imaging material, excluding the support, of 1 to 10% by weight, and one or more reactive compounds.
  • the feature "reactive compound” shall be understood as a compound which undergoes a (physico-)chemical reaction due to the heat generated during image-wise exposure.
  • reactive compounds are thermoplastic polymer latex, diazo resins, naphtoquinone diazide, photopolymers, resole and novolac resins, or modified poly(vinyl butyral) binders. More examples can be found in J. Prakt. Chem. Vol. 336 (1994), p. 377-389.
  • Preferred materials used in the present invention comprise less than 20% by weight of such other reactive compounds besides the light absorbing compound. Such materials exhibit an excellent stability : they can be stored during 2 minutes at 100°C without toning (ink acceptance in non-exposed areas), contrary to conventional thermal lithographic printing plate precursors which show significant toning when exposed to the above conditions. Some materials, especially those comprising carbon as a light absorbing compound, can even be stored during 2 minutes at 150°C without noticeable toning.
  • the amount of said reactive compounds is less than 10% by weight and most preferably, the imaging material is substantially free from reactive compounds other than the light absorbing compound.
  • the words "substantially free” shall be understood as meaning that a small ineffective amount of such reactive compounds may be present in addition to the light absorbing compound. Said small ineffective amount is not essential for or does not significantly contribute to the imaging process of the material.
  • the imaging materials that are used in the present invention may further comprise non-reactive compounds, i.e. inert components such as e.g. a binder, surfactant, matting agent or filler.
  • inert components such as e.g. a binder, surfactant, matting agent or filler.
  • inert components such as e.g. a binder, surfactant, matting agent or filler.
  • inert components e.g. a binder, surfactant, matting agent or filler.
  • inert components such as e.g. a binder, surfactant, matting agent or filler.
  • inert components such as e.g. a binder, surfactant, matting agent or filler.
  • inert components such as e.g. a binder, surfactant, matting agent or filler.
  • hydrophilic binders e.g. carboxymethyl cellulose, homopolymers and copolymers of vinyl pyrrolidone, vinyl alcohol, acrylamide, methylol acrylamide, methylol methacrylamide, acrylic acid, methacrylic acid, hydroxyethyl acrylate, hydroxyethyl methacrylate or maleic anhydride/vinylmethylether copolymers.
  • the amount of hydrophilic binder in the layer(s) provided on the support is preferably less than 40% by weight and more preferably between 5 and 20% by weight.
  • a highly preferred imaging material for wet lithographic printing according to the present invention comprises a grained and anodised aluminium support and provided directly thereon a single layer which consists essentially of a light absorbing compound such as carbon, graphite or soot and is substantially free from other reactive compounds.
  • the recording layer is preferably provided on top of a silicone layer.
  • the ink-abhesive layer is a silicone coating which contains one or more components one of which is generally a linear silicone polymer terminated with a chemically reactive group at both ends and a multifunctional component as a hardening agent.
  • the silicone coating is preferably crosslinked, e.g. by condensation curing, addition curing or radiation curing.
  • the ink-abhesive layer may also comprise other ingredients, e.g. plasticisers, pigments, dyes, etc.
  • the recording layer can be applied on the support by coating or spraying an image recording composition.
  • Said composition can be applied directly on the surface of a cylinder of a rotary printing press. More preferably, such image recording composition is applied on a sheet or belt which is mounted on a cylinder of a rotary printing press.
  • On-press coating of a recording layer can be carried out by using the inking system of the plate cylinder as a coating system.
  • said composition can be applied off-press in a dedicated coating apparatus on a plate or sleeve which, after image-wise exposure and optional processing, is then transferred to a cylinder of a rotary printing press.
  • said coating apparatus is mechanically coupled to said printing press so that the imaging material can be transferred automatically to the printing press.
  • Jet methods such as ink jet or toner jet can be used as an alternative coating technique, whereby either a uniform layer of light absorbing compound is jet-coated on the support and then image-wise exposed or whereby the light absorbing compound is image-wise applied to the support and then rendered ink accepting by intense heating, e.g. by laser exposure.
  • a support can also be provided with a recording layer by rubbing in the support with a dry powder comprising a light absorbing compound, e.g. carbon or an organic dye.
  • a dry powder comprising a light absorbing compound, e.g. carbon or an organic dye.
  • said support may already have been provided with another layer before being rubbed in with said dry powder.
  • Alternative dry coating methods can also be used, e.g. sputter-coating of carbon or direct electrostatic printing (toner jet). The latter technique can be used to apply the dry powder image-wise and after intense overall heating, e.g. by infrared laser exposure, a printing master is obtained. Said infrared laser can be mounted on the same carriage as the direct electrostatic printing head.
  • the recording layer may also be applied as a dry powder by contacting the support with another material, which carries a dry layer containing a light absorbing compound which is then transferred to the support. Suitable examples are rubbing in the support with ashes, charcoal, or a semi-burned piece of organic material such as a cork or wood.
  • the method of the latter embodiment can be automated easily, e.g. by incorporating a supply roll of such a transfer material, such as a ribbon impregnated with light absorbing compound or carrying a recording layer comprising a binder and a light absorbing compound, in a print station of a digital press similar to the configuration which is described in EP-A 698 488.
  • the transfer material can be unwound from said supply roll and the side containing the light absorbing compound can then be brought into direct contact by one or more contact rollers with the surface of a plate cylinder or a support mounted thereon.
  • the transfer step which may be carried out by applying pressure and/or heat on said transfer material while being in contact with the support, the used transfer material may be wound up again on a take-up roll.
  • the transfer can be carried out so as to obtain a uniform layer which then can be image-wise exposed.
  • said pressure and/or heat can be applied image-wise, so that the light absorbing compound or recording layer is transferred image-wise to the support.
  • This step then may be followed by intense overall heating, e.g. by laser exposure. However, if sufficient heat is applied during said image-wise transfer, a suitable printing master may directly be obtained without said intense heating.
  • the recording layer consists essentially of or comprises soot as a light absorbing compound, i.e. the black carbon obtained from the incomplete combustion of organic materials such as oils, wood, natural gas, acetylene, coal, wax or cork.
  • soot may even be applied by contacting the support with a flame obtained by burning said organic material.
  • the surface of the support is contacted with the colder part of the flame where combustion is incomplete, e.g. the yellow end of the flame of a candle. Electron microscopic images of materials made in this way show the presence of submicron soot particles.
  • the recording layer may be a continuous or a non-continuous layer.
  • the feature "recording layer” also embraces a non-continuous layer, irrespective of the scale of the non-covered areas, which may be even macroscopic, e.g. in the case of image-wise application of a recording layer as discussed above.
  • the composition is highly stable and shows excellent shelf-life, the composition can easily be applied by the on-press coating methods described herein, the coated layer shows high sensitivity for heat-mode imaging by a laser using a internal as well as an external drum configuration, the exposed layer is developed simply by applying a conventional dampening liquid, the lithographic performance of the printing master thus obtained is excellent, and after the pressrun, the printing surface can be erased easily using the atmospheric plasma treatment described above.
  • the support can then be re-coated and, after exposure and optional development, another print job can be started.
  • Preferred imaging materials used in the present invention can be exposed to light by a light emitting diode or a laser such as a He/Ne or Ar laser.
  • a laser emitting near infrared light having a wavelength in the range from about 700 to about 1500 nm is used, e.g. a semiconductor laser diode, a Nd:YAG or a Nd:YLF laser.
  • the required laser power depends on the pixel dwell time of the laser beam, which is determined by the spot diameter (typical value of modern plate-setters at 1/e 2 of maximum intensity : 10-25 ⁇ m), the scan speed and the resolution of the exposure device (i.e.
  • ITD image-setters are typically characterised by a very high scan speed up to 500 m/sec and may require a laser power of several Watts. Satisfactory results have also been obtained by using XTD image-setters having a typical laser power from about 200 mW to about 1 W at a lower scan speed, e.g. from 0.1 to 10 m/sec.
  • the imaging materials used in the present invention are preferably capable of being processed simply by starting a pressrun, e.g. due to the mechanical friction between the material and a contacting cylinder or due to dissolution of the recording layer in the ink or fountain which are applied onto the printing surface.
  • the materials described in the co-owned EP-As cited above can be processed by removing the non-exposed recording layer during the first few runs of the printing job.
  • the recording layer comprises a pigment or dye which absorbs visible light, its removal may be observed as a fog present in the non-printing areas of the first printed copies.
  • the imaging material can also be processed before printing, e.g.
  • processing steps may be performed on-press or off-press.
  • the exposure and processing steps may also be performed in an apparatus which is mechanically coupled to the printing press so that the printing master can be transferred automatically to the printing press.
  • the surface of an anodised aluminium support was covered with a soot layer by contacting said surface with the flame of a Bunsen burner fed with natural gas. After coating the whole support, the layer was rubbed off with a dry cloth so as to obtain a thin layer of soot.
  • the plate precursor thus obtained was image-wise exposed in heat-mode with a Nd:YLF (1060 nm) external drum (XTD) laser having a power of 738 mW and a scan speed of 8.0 m/sec.
  • the plate was mounted on the cylinder of an AB Dick 360 (trade name) printing press and cleaned with a sponge moistened with plain water.
  • a pressrun of 25000 copies was started using Rubber Base Plus VS2329 Universal Black ink, trade name of Van Son, and Tame EC 7035 fountain, trade name of Anchor, the latter diluted with water 50-fold. The print quality was very good throughout the pressrun.
  • the soot layer was removed by a treatment with an atmospheric plasma jet using a PlasmaTreat® nozzle (trademark of Agrodyn Hochputtechnik GmbH, Steinhagen, Germany) at an operating RF voltage of 20 kV / 18 kHz, generated by an Agrodyn frequency generator type FG1001 (in: 230 V, 50-60 kHz; out: 1 kV, 16-20 kHz) and an Agrodyn transformator type HTR1001 (in: 1 kV, 16-20 kHz; out: 20 kV, 16-20 kHz) (also trademarks of Agrodyn Hochputtechnik GmbH). After this cleaning step, the aluminium plate could be reused for making another printing master.
  • FG1001 in: 230 V, 50-60 kHz; out: 1 kV, 16-20 kHz
  • HTR1001 in: 1 kV, 16-20 kHz; out: 20 kV, 16-20 kHz
  • the aluminium plate could be reused for making another printing master.
  • Silicone Dehesive 520 has an average molecular weight of about 5000.
  • the sample was cured at 90 °C during 40 seconds and then rubbed in with a semi-burned cork. The recording layer thus obtained was tamped with a cotton pad so as to obtain a relatively homogenous top layer of soot.
  • a test pattern was exposed in heat-mode using an XTD Nd:YAG image-setter (spot-size at 1/e 2 : 23 ⁇ m) at a scan speed of 1 and 2 m/sec and a power of 350, 400 and 450 mW (six different exposures at distinct areas of each sample).
  • the image pattern was visible immediately after exposure.
  • the plate was then processed by rubbing with a cotton pad that was moistened with water while being mounted on the plate cylinder of an AB Dick 9860 printing press.
  • a pressrun of 100 copies was started using Reflecta Dry Magenta ink, trade name of Hostmann-Steinberg (Celle, Germany), without using a fountain.
  • the plate was cleaned using the same apparatus as described in Example 1.
  • the aluminium plate carrying said silicon layer could be reused for making another printing master.

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  • Manufacture Or Reproduction Of Printing Formes (AREA)
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Claims (10)

  1. Procédé pour éliminer les zones acceptant l'encre d'une surface d'impression d'une matrice d'impression lithographique en traitant ladite surface d'impression avec un plasma atmosphérique.
  2. Procédé selon la revendication 1, dans lequel la surface d'impression est traitée en dirigeant un jet de plasma atmosphérique sur la surface d'impression et en déplaçant par balayage ledit jet de plasma par rapport à ladite surface.
  3. Procédé d'impression lithographique avec une presse d'impression, comprenant les étapes ci-après consistant à :
    (i) fabriquer un matériau de formation d'image en munissant un support d'une couche d'enregistrement d'image ;
    (ii) fabriquer une matrice d'impression possédant une surface d'impression comprenant des zones acceptant l'encre par exposition en forme d'image et le cas échéant par développement du matériau de formation d'image ;
    (iii) démarrer un tirage ; te
    (iv) mettre en oeuvre un procédé selon la revendication 1 ou 2.
  4. Procédé selon la revendication 3, dans lequel toutes les étapes (i) à (iv) sont mises en oeuvre dans une presse d'impression ou dans un appareil et qui est couplé par voie mécanique à la presse d'impression, et dans lequel le support est un cylindre de la presse d'impression ou encore une feuille, un cliché, une courroie ou un manchon qui est monté sur ledit cylindre.
  5. Procédé selon la revendication 3 ou 4, dans lequel le matériau de formation d'image comprend une ou plusieurs couches contenant un composé absorbant la lumière en une quantité qui n'est pas inférieure à 50 % en poids par rapport à la totalité des couches dudit matériau de formation d'image, à l'exclusion du support.
  6. Procédé selon l'une quelconque des revendications 3 à 5, dans lequel la couche d'enregistrement comprend un composé absorbant la lumière en une quantité qui n'est pas inférieure à 70 % en poids.
  7. Procédé selon l'une quelconque des revendications 3 à 5, dans lequel la couche d'enregistrement est constituée essentiellement du composé absorbant la lumière.
  8. Procédé selon l'une quelconque des revendications 3 à 7, dans lequel le composé absorbant la lumière est du carbone, du graphite ou de la suie.
  9. Procédé selon l'une quelconque des revendications 3 à 8, dans lequel la matrice d'impression est une matrice d'impression driographique et la couche d'enregistrement est prévue sur un support manifestant une aversion pour l'encre ou sur une couche manifestant une aversion pour l'encre qui est portée par le support.
  10. Procédé selon l'une quelconque des revendications 3 à 8, dans lequel la matrice d'impression est une matrice d'impression lithographique mouillée et la couche d'enregistrement est prévue sur un support hydrophile ou sur une couche hydrophile qui est portée par le support.
EP99202799A 1999-08-31 1999-08-31 Méthode de régénération d'une plaque d'impression lithographique Expired - Lifetime EP1080942B2 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP99202799A EP1080942B2 (fr) 1999-08-31 1999-08-31 Méthode de régénération d'une plaque d'impression lithographique
DE69913518T DE69913518T2 (de) 1999-08-31 1999-08-31 Verfahren zur Erneuerung einer Flachdruckplatte
US09/638,877 US6408755B1 (en) 1999-08-31 2000-08-15 Method for erasing a lithographic printing master
JP2000258756A JP2001105763A (ja) 1999-08-31 2000-08-29 平版印刷マスターの消去方法

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EP99202799A EP1080942B2 (fr) 1999-08-31 1999-08-31 Méthode de régénération d'une plaque d'impression lithographique

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EP1080942A1 EP1080942A1 (fr) 2001-03-07
EP1080942B1 true EP1080942B1 (fr) 2003-12-10
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DE10206946A1 (de) * 2002-02-19 2003-09-04 Oce Printing Systems Gmbh Verfahren und Einrichtung zum Drucken, wobei eine Hydrophilisierung des Druckträgers durch freie Ionen erfolgt
DE102005028817A1 (de) * 2005-06-22 2007-01-11 Man Roland Druckmaschinen Ag Verfahren zur Herstellung von Druckformen
CN112630288B (zh) * 2020-11-17 2021-10-12 燕山大学 一种基于放电的二次电子发射系数测量装置及方法

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JPS5654440A (en) * 1979-10-11 1981-05-14 Dainippon Printing Co Ltd Photosensitive lithographic material and plate making method
US4777109A (en) * 1987-05-11 1988-10-11 Robert Gumbinner RF plasma treated photosensitive lithographic printing plates
US5062364A (en) † 1989-03-29 1991-11-05 Presstek, Inc. Plasma-jet imaging method
EP0502855A1 (fr) * 1990-09-28 1992-09-16 Presstek, Inc. Procede et appareil d'impression a jets de plasma
RU2030811C1 (ru) * 1991-05-24 1995-03-10 Инженерный центр "Плазмодинамика" Установка для плазменной обработки твердого тела
DE4123959C1 (fr) † 1991-07-19 1993-02-04 Man Roland Druckmaschinen Ag, 6050 Offenbach, De
DE19503951C2 (de) * 1995-02-07 1998-04-09 Roland Man Druckmasch Verfahren und Vorrichtung für den Tiefdruck
JPH0942273A (ja) * 1995-08-01 1997-02-10 Canon Inc 電子写真プロセス用円筒部品の再生方法
DE19532412C2 (de) † 1995-09-01 1999-09-30 Agrodyn Hochspannungstechnik G Vorrichtung zur Oberflächen-Vorbehandlung von Werkstücken
US5789145A (en) * 1996-07-23 1998-08-04 Eastman Kodak Company Atmospheric pressure glow discharge treatment of base material for photographic applications

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EP1080942B2 (fr) 2009-10-14
DE69913518T2 (de) 2004-11-11
JP2001105763A (ja) 2001-04-17
DE69913518D1 (de) 2004-01-22
EP1080942A1 (fr) 2001-03-07

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