EP1266093B1 - Application device and process - Google Patents

Application device and process Download PDF

Info

Publication number
EP1266093B1
EP1266093B1 EP01913875A EP01913875A EP1266093B1 EP 1266093 B1 EP1266093 B1 EP 1266093B1 EP 01913875 A EP01913875 A EP 01913875A EP 01913875 A EP01913875 A EP 01913875A EP 1266093 B1 EP1266093 B1 EP 1266093B1
Authority
EP
European Patent Office
Prior art keywords
application
substrate
applicator unit
application medium
electrode arrangement
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
EP01913875A
Other languages
German (de)
French (fr)
Other versions
EP1266093A1 (en
EP1266093B2 (en
Inventor
Benjamin Mendez-Gallon
Manfred Ueberschär
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.)
Voith Patent GmbH
Original Assignee
Voith Paper Patent GmbH
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
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=26004823&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP1266093(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Priority claimed from DE2000112256 external-priority patent/DE10012256A1/en
Priority claimed from DE2000112347 external-priority patent/DE10012347A1/en
Application filed by Voith Paper Patent GmbH filed Critical Voith Paper Patent GmbH
Publication of EP1266093A1 publication Critical patent/EP1266093A1/en
Publication of EP1266093B1 publication Critical patent/EP1266093B1/en
Application granted granted Critical
Publication of EP1266093B2 publication Critical patent/EP1266093B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H23/00—Processes or apparatus for adding material to the pulp or to the paper
    • D21H23/02—Processes or apparatus for adding material to the pulp or to the paper characterised by the manner in which substances are added
    • D21H23/22—Addition to the formed paper
    • D21H23/46—Pouring or allowing the fluid to flow in a continuous stream on to the surface, the entire stream being carried away by the paper
    • D21H23/48—Curtain coaters
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05C5/00—Apparatus in which liquid or other fluent material is projected, poured or allowed to flow on to the surface of the work
    • B05C5/005—Curtain coaters

Definitions

  • the invention relates to a device for one-sided or two-sided Apply liquid or pasty application medium to a running one Subsurface, comprising one arranged at a distance from the subsurface Application work, which is the application medium in the free application medium jet releases to the underground, whereby the underground with direct Apply the surface of a material web, especially paper or Carton, and with indirect application the surface of a transfer element, preferably a transfer roller, which is the application medium transfers to the surface of the material web, according to the generic terms of Claims 1, 5 and 27.
  • curtain applicator also known as “curtain coating”
  • the application medium to the surface in the form of an application medium curtain issued, which is due to gravity from Commissioned work moved to the underground. That the curtain commission is at a predetermined distance from the surface Among other things, it has the advantage that it breaks down, for example is exposed to a lower risk of damage.
  • Curtain coaters differ from other "contactless" commissions, for example free jet nozzle applicators, in which the movement of the order medium from the order work to the underground mainly comes from the ejection impulse from the delivery nozzle of the application unit, fundamental since the shape of the emerging from the dispensing nozzle Curtain only the interplay between the surface tension of the application medium and gravity.
  • the surface tension tries to make the curtain based on its volume or its cross-sectional area has a very large surface or Has circumferential length to contract so as to its surface reduce. Only gravity opposes this effect Tries to stretch the curtain. It is therefore easy to see that it is all the more it is more difficult to have a uniform thickness across the entire working width Obtain order medium curtain, the larger this working width.
  • a device of the type mentioned is from DE 197 16 466 A1 known.
  • This document shows a device for applying Dispersions on a material web by a so-called curtain coating application process.
  • the application medium curtain extending one by one Commissioned edge guide element running towards the material web arranged, depending on the embodiment of the application medium may or may not be wetted.
  • the order medium curtain will have edge guiding elements on it lateral edges due to adhesive forces in the transverse direction of the material web stretched.
  • these are as Electrodes formed, which generate an electric field, the such that acts on the side edges of the application medium curtain this is stretched in the transverse direction of the material web.
  • the application medium curtain through the mentioned device can only be influenced at its lateral edges is. This can be unsatisfactory, especially with large working widths Maintain order results especially in the middle of the working width.
  • WO 97/03009 deals with the problem of drying Material webs after applying media, namely printing inks, especially in gravure web offset and flexo printing. She suggests that Gas molecules on the surface of the material web by means of a corona discharge to ionize and accelerate towards an electrode to through the gas exchange associated with this "ion wind" at the Material surface to increase the drying efficiency.
  • DE 1 98 03 240 A1 discloses a curtain coating application device, which is a sensor device for detecting the amount of coating on the Application medium layer applied and a layer Control device for regulating the order quantity includes.
  • the Order quantity is determined by changing the gap width of the Order medium outlet gap regulated at the order plant.
  • EP 0 937 815 A1 shows a device for applying a liquid or pasty application medium through an application medium jet, at which enlarges the application area by means of aperture elements or can be reduced by the side edges of the Order area forth in the cross direction of the web so Application medium nozzles can be moved, that of these outgoing application medium jet is intercepted by the aperture and the material web has not reached.
  • the application medium jet moves in the case of the invention Application device not only under the influence of gravity or not only under the influence of the ejection pulse from the discharge nozzle to the underground. Rather, this movement is accompanied by an additional one Force supported by the field generating device on the Application medium beam is exerted and the beam on its way from the dispensing nozzle tries to stretch to the surface (pre-stretching). Therefore can be used in particular for "curtain coating commissioned works" equal distance between the dispensing nozzle and the surface the stability of the Jet increased, or the distance between the dispensing nozzle and For a given desired radiation stability, choose a larger surface become.
  • the Total stretch of the application medium from one to the other Dispensing nozzle determines the jet thickness up to the thickness of the ultimately the substrate applied layer of application medium from the Product of the beam stretching on the beam described above Away from the dispensing nozzle to the surface and the contact extension composed of the difference between the speed the beam immediately before it hits the ground and the Running speed of the surface when the application medium comes into contact comes from the underground.
  • the order layer if the Total stretching as evenly as possible from pre-stretching and contact stretching composed. Because the application medium jet is all the more vulnerable for external influences, for example for the influence of the underground air boundary layer, the longer the path of the application medium from the discharge nozzle to the surface, this always runs in practice on the Desire for the strongest possible advance.
  • the electric field on the Application medium jet also exerted a force that is orthogonal to one whose direction of movement has a running component, i.e. the Electrode arrangement attracts the application medium jet.
  • This too Force component helps the application medium jet against the influence the air boundary layer carried on the surface of the subsurface stabilize.
  • an electrode arrangement on the upstream side of the Commissioned work and in its vicinity an electrode arrangement be provided which on a predetermined electrical Electrode arrangement potential is kept.
  • “Additional” means that both the application and the electrode arrangement on one predetermined potential different from the earth potential.
  • alternate means that only the electrode arrangement is on a predetermined potential different from the earth potential are while the work is either grounded or its electrical potential is in suspension ("floating potential").
  • the object of the present invention is achieved according to a second Aspect of the invention by the "alternative" just described Provision of an electrode arrangement, namely by a Application device with the features of claim 5 solved.
  • the electrode arrangement can comprise at least one flat electrode.
  • the flat electrode can be on its side facing the surface have a plurality of protrusions or needle tips.
  • needle tips or needle electrodes can achieve that the electrode arrangement does not only reflect its surroundings by that Earth potential formed electric field, but that it affects above discharge processes may also occur, in which the Ambient air is at least partially ionized, and the resulting Charge carriers for charging the application medium jet, for example to lead. After such charging, the movement of the Application medium beam even more effectively through the electric field to be influenced.
  • the A device strikes the position of the application medium on the substrate is provided for generating an electric field.
  • This electrical Field exercises a on the application medium applied to the surface force directed towards the underground, what in places, too much Application medium has been applied to displace the excess Order medium leads.
  • the further field generating device preferably has one Background adjacent further electrode arrangement, which preferably at a further predetermined electrical potential is held.
  • Such an application medium applied to the substrate Basically, pulling force can also come from one Residual charging of the application medium applied to the surface as a result of discharges induced by the first electrode arrangement originate.
  • That or the predetermined electrical different from the earth potential Potentials can have a value of between 5 kV and approximately, for example 60 kV, preferably about 30 kV.
  • the subsurface is preferably on Earth potential held.
  • a counter element preferably a counter roller, which with direct Order supports or supports the material web in the area of the order plant whose surface the application work the application medium with indirect Application, is in contact with an electrode to place it on the to hold the second predetermined electrical potential.
  • the, for example metallic or rubberized, surface of the counter element with the electrode is in sliding contact.
  • the Electrode with a bearing shaft of the counter roller in an electrically conductive Contact is there.
  • the material web is used, for example, as a web guiding element trained electrode on the second predetermined electrical Potential, so preferably the earth potential.
  • the influence of the air boundary layer carried on the surface of the subsurface to be able to keep the application medium jet low proposed that the electrode arrangement in the running direction of the Underground a device for weakening the surface is carried upstream air boundary layer.
  • the Air boundary layer weakening device a suction device include, with the help of the air boundary layer actively from the current Can be removed.
  • Drag scraper in contact with the ground be provided.
  • This drag scraper seals the suction device Environment and hinders the further movement of the air boundary layer to the commissioned work.
  • the in the air boundary layer entrained air pent-up what the laminar character of the flow the air boundary layer at least partially destroyed. This makes it easier Suction and increases the suction efficiency of the suction device. So can the air boundary layer through the one designed according to the invention Suction device weakened particularly effectively, if not completely be removed from the ground.
  • the drag scraper can be a flexible film, preferably made of plastic, Metal sheet or a composite material may be formed.
  • the flexible Foil nestles against the suction of the suction device the underground, which improves the sealing on the one hand and prevents others from building a new air boundary layer.
  • the Drag scraper made of sheet metal, preferably stainless steel sheet with a thickness of at most 0.1 mm.
  • scrapers made of composite material with a Surface coating made of Teflon proven The composite material ensures thereby for the required temperature resistance and flexibility, while the Teflon surface coating for low friction between the drag scraper and the running surface.
  • the drag scraper can be curved in the running direction, which is the elastic dodging eases and friction with the ground further diminishes.
  • the further electrode arrangement can in principle be connected to an external one Power supply must be connected. However, it is also possible and constructively even easier to implement if the electrical Potential of the further electrode arrangement is kept in suspense ("floating potential"). In this case, the further electrode arrangement due to the discharges emanating from the first electrode arrangement charged and thus also to a different from the ground potential Brought potential. To reduce the capacity of the further electrode arrangement and for security reasons, it is proposed that the further electrode arrangement on the suction device of this electrically is arranged in isolation.
  • This The beam can be narrowed by providing edge guide elements be prevented, since in this case between the order medium and additional adhesion forces on the surface of the edge guide elements act which of the surface tension of the Contradict the outgoing narrowing tendency.
  • the object of the invention therefore solved by a device with the features of claim 27.
  • edge guide elements this has a structured surface.
  • Surface of at least one edge guide element roughened and / or has a toothed surface, for example in the form of a External thread or an internal thread.
  • the adhesion between the edge guide elements and the Application medium can be improved in that the Surface properties of at least one edge guide element are chosen so that the properties of the application medium and dependent on the surface of the edge guide elements Contact angle is less than 90 °.
  • the edge guide elements can be made of glass or metal, for example be made because these materials have a sufficiently high surface tension exhibit. With metals, however, it should be noted that some Metals tend to get water vapor from the atmosphere surrounding them to adsorb, causing their surface tension to increase in value the adsorbed water layer sinks.
  • At least one edge guide element slidably arranged in the transverse direction of the substrate is and / or that the angle that an edge guide element with the Includes vertical, is adjustable.
  • the Angular adjustability a pivoting of the free ends of the edge guide elements in the transverse direction and / or in the longitudinal direction.
  • the effect of the edge guide elements can also by Providing an electric field can be improved, for example in that near at least one of the edge guide elements, preferably running essentially parallel to this, an electrode is provided, which is at a predetermined electrical potential is held.
  • an application device is generally at 10 designated. It comprises a curtain application unit 12 with a Dispensing nozzle 14, from the application medium 16 in the form of a curtain 18th is delivered to a substrate U moving in the direction of travel L.
  • the subsurface U is the surface 20a of a material web 20, which in the area of the application unit 12 Circumferential surfaces of a support roller 22 partially wrapped.
  • the application medium 16 On its way from the dispensing nozzle 14 to the substrate U, the application medium 16 accelerated. This leads to a reduction in thickness of the curtain 18 from the value D in the region of the dispensing nozzle 14 to the Value d immediately before the impact position P on the underground U (Pre-stretching). Due to the difference between the speeds the application medium curtain 18 immediately before the impact position P and The application medium 16 becomes the running speed of the underground U stretched again when hitting the underground U, so that the on the application layer 24 applied to the substrate U ultimately the thickness s has (contact extension). The total stretch of the order medium 16 is the product of the stretching factors of pre-stretching and Contact extension.
  • the application medium 16 becomes when it hits the surface U usually stretched more than on the way from the dispensing nozzle 14 to the underground U, since one is as stable as possible Curtain 18 the distance between the dispensing nozzle 14 and the underground U cannot choose any size. Too much contact extension works but adversely affect the uniformity of the underground U applied application layer 24.
  • the application device 10 now offers a possibility with the help of which one either has the same head between the dispensing nozzle 14 and underground U can intensify the pre-stretching of the curtain 18 or how to drop the height between the dispensing nozzle with the same pre-stretching 14 and reduce underground U and thus stabilize the curtain 18 can.
  • the application medium curtain 18 is opened its way from the dispensing nozzle 14 to the underground U not only the Gravity left, but there will be additional electrostatic on it Powers exercised. This strengthening of the curtain 18 stretching Has forces, since the surface tension of the application medium 16, the Curtain 18 in the sense of reducing its surface tries to contract, remains constant, a higher stability of the Application medium curtain 18 result.
  • the electrostatic forces could be provided by applying a first predetermined electrical voltage V 1 to the housing of the application unit 12 and the support roller 22 on the
  • an electrode arrangement 30 is provided in the running direction L directly in front of the application unit 12, which can for example comprise a flat electrode extending in the transverse direction Q with a plurality of needle tips, or formed by a plurality of needle electrodes 32 arranged adjacent to one another in the transverse direction Q. can.
  • a predetermined electrical voltage V 3 is applied to the electrode arrangement 30, while the parts of the application device 10 surrounding it, namely the application unit 12, the support roller 22 and a suction box 34 provided upstream of the electrode arrangement 30 with respect to the running direction L for weakening a material web 20 entrained air boundary layer are kept at ground or earth potential V E.
  • the curtain 18 due to the discharges E also exerted a force that is orthogonal to the direction of its fall running component. This force component too helps to remove the application medium curtain 18 from the influence of the Surface of the material web 20 entrained air boundary layer G to stabilize.
  • the suction box 34 is used for Weakening of the air boundary layer G.
  • a drag scraper 36 is provided on the outlet side of this suction box 34, which is in sliding contact with the surface 20a of the material web 20 and seals the suction area of the suction box 34 on the outlet side.
  • the drag scraper 36 can, for example, be made of a Teflon-coated material Be made of composite material. Due to the use of a composite material the drag scraper 36 has sufficient temperature resistance and flexibility, and because of the surface coating sufficient friction with Teflon.
  • the further electrode arrangement 40 can either be from a flat electrode with a plurality of needle tips or a plurality of in Transverse direction Q needle electrodes arranged adjacent to each other be educated.
  • the electrode arrangement 40 can be connected to a external power supply must be connected.
  • the illustrated Embodiment is in terms of its electrical Potentials, however, in a floating state ("floating potential"), however as a result of the discharges E charged and thus also to a different from the ground potential Brought potential.
  • the charge of the electrode arrangement 40 is sufficient to it between the tips of the electrode assembly 40 and the ground U also allow discharges to occur. These discharges e disrupt the laminar flow of the air boundary layer G and convert it at least partially into a turbulent flow. This makes it easier Aspirating the air boundary layer G from the surface 20a of the material web and thus improves the effectiveness of the suction box 34.
  • electrical forces can also contribute to improving the leveling and fixing of the application layer 24 on the material web 20.
  • a further electrode arrangement in the form of a plate electrode 46 can be provided, which is kept at a predetermined electrical potential V 4 .
  • a relatively homogeneous electric field is formed between this plate electrode 46 and the support roller 22 held at ground potential, which exerts a force directed toward the substrate U on the application medium.
  • this force causes the excess application medium to be displaced and thus to even out the application layer 24.
  • areas of the material web surface 20a which have not been covered up to now can occur as a result of this Force be covered with application medium 16 for the first time.
  • the force mentioned above also improves the bond that the application medium 16 enters into with the surface 20a of the material web 20.
  • the support roller 22 can be kept at the ground potential V E in different ways.
  • the roller axis A can be connected to a sliding contact, as described, for example, in DE 197 33 333 A1. Additionally or alternatively, however, a sliding contact 50 connected to the surface 22a of the roller 22 can also be provided.
  • the material web 20 can also be held at ground potential V E via contacts formed by web guiding elements 48, for example.
  • FIG. 2 is a view taken with the viewing direction in the running direction L. the application device 10 shown. Based on this representation, a Possibility to explain how the application medium curtain 18 also in the Area of its side edges 18a can be stabilized.
  • the the curtain 18 contracting surface tension of the application medium 16 acts mainly in the edge areas 18 of the Curtain 18 out. There it leads to a lateral contraction of the Curtain 18 and its thickening.
  • guide strips 54 in the embodiment shown in FIG. 2 provided which are attached to the applicator 12 such that they catch and open the curtain 18 emerging from the dispensing nozzle 14 its fall path up to just in front of the surface 20a of the material web 20 to lead.
  • edge strips 54 The effect of the edge strips 54 is based on the adhesive forces between the application medium 16 and the surface of the edge strips 54.
  • the contact angle or Wetting angle ⁇ of a droplet T of application medium 16 on the Surface 54a of the edge strips 54 has the lowest possible value exhibit. This can be achieved, for example, by: the surface of the edge strips 54 made of a material with high Creates surface tension.
  • wetting between application medium 16 and edge strips 54 by a roughened, for example, toothed surface structure of the edge strips 54 is improved become. This can be achieved, for example, by: Threaded rods used as edge strips 54.
  • a further possibility in order to be able to improve the adhesion of the application medium 16 to the edge strips 54 is to provide electrode strips 56 essentially parallel to the edge strips 54, to which a predetermined electrical voltage V 5 is applied. As a result, an attractive force is exerted on the application medium in a manner similar to that described above for the arrangement according to FIG. 1.
  • Edge strips 54 To the edge strips 54 to the desired working width, i.e. the to be able to adjust the respective present width of the material web 20 these are arranged displaceably in the transverse direction Q on the application unit 12, what is indicated in Fig. 2 by the arrows q.
  • the Edge strips 54 are also pivotally arranged on the application unit 12 be, namely to the longitudinal direction L or / and the transverse direction Q in Essentially parallel axes, with the arrows in FIG. 2 I only a pivotability in the transverse direction Q, i.e. for one for Longitudinal direction L substantially parallel axis is indicated.

Abstract

The invention relates to a device (10) for directly or indirectly applying liquid or pasty application medium (16) to one or both sides of a material web (20) made of, in particular, paper or paperboard. The device comprises an application mechanism (12) which delivers the application medium (16) in the form of a free application medium stream (18) onto the material web (20). To this end, a device (30) for generating an electric field is provided in the vicinity of the application mechanism (12). Said electric field exerts a force onto the application medium stream (18), which is moving from the application mechanism (12) to the material web (20), while assisting the movement of said application stream (18). In addition or alternatively, edge guiding elements can be provided which guide the lateral edges of the application medium curtain (18) at least along a portion of the gravity-related movement thereof.

Description

Die Erfindung betrifft eine Vorrichtung zum einseitigen oder beidseitigen Auftragen von flüssigem oder pastösem Auftragsmedium auf einen laufenden Untergrund, umfassend ein vom Untergrund mit Abstand angeordnetes Auftragswerk, welches das Auftragsmedium im freien Auftragsmedium-Strahl an den Untergrund abgibt, wobei der Untergrund bei direktem Auftrag die Oberfläche einer Materialbahn, insbesondere aus Papier oder Karton, und bei indirektem Auftrag die Oberfläche eines Übertragselements, vorzugsweise einer Übertragswalze, ist, welches das Auftragsmedium dann an die Oberfläche der Materialbahn überträgt, gemäß den Oberbegriffen der Ansprüche 1, 5 und 27.The invention relates to a device for one-sided or two-sided Apply liquid or pasty application medium to a running one Subsurface, comprising one arranged at a distance from the subsurface Application work, which is the application medium in the free application medium jet releases to the underground, whereby the underground with direct Apply the surface of a material web, especially paper or Carton, and with indirect application the surface of a transfer element, preferably a transfer roller, which is the application medium transfers to the surface of the material web, according to the generic terms of Claims 1, 5 and 27.

Obgleich die Erfindung auch bei anderen "kontaktlos" arbeitenden Auftragsvorrichtungen mit Vorteil eingesetzt werden kann, beispielsweise Auftragsvorrichtungen mit einem Freistrahl-Düsenauftragswerk, welches das Auftragsmedium an den Untergrund als Auftragsmedium-Strahl abgibt, welcher sich im Wesentlichen aufgrund des ihm vom Auftragswerk verliehenen Ausstoßimpulses vom Auftragswerk zum Untergrund bewegt, wird die Erfindung nachfolgend am Beispiel einer Vorhang-Auftragsvorrichtung näher erläutert werden, d.h. einer Auftragsvorrichtung, bei welcher das Auftragswerk das Auftragsmedium als sich im Wesentlichen schwerkraftbedingt bewegenden Vorhang oder Schleier an den Untergrund abgibt.Although the invention also works with other "contactless" Application devices can be used with advantage, for example Applicators with a free jet nozzle applicator, which emits the application medium to the substrate as an application medium jet, which is essentially due to the fact that it lent output impulse moved from the commissioned work to the underground, The invention is illustrated below using the example of a curtain application device are explained in more detail, i.e. an application device, at which the commissioned work the order medium as essentially gravity moving curtain or veil on the surface emits.

Bei der Beschichtung von Materialbahnen unter Einsatz eines Vorhang-Auftragswerks (in der Fachwelt auch als "Curtain Coating" bekannt) wird das Auftragsmedium an den Untergrund in Form eines Auftragsmedium-Vorhangs abgegeben, der sich im Wesentlichen schwerkraftbedingt vom Auftragswerk zum Untergrund bewegt. Dass das Vorhang-Auftragswerk sich dabei in einem vorbestimmten Abstand vom Untergrund befindet, hat unter anderem den Vorteil, dass es beispielsweise bei einem Bahnabriss einem geringeren Beschädigungsrisiko ausgesetzt ist. Vorhang-Auftragswerke unterscheiden sich von anderen "kontaktlosen" Auftragswerken, beispielsweise Freistrahl-Düsenauftragswerken, bei welchen die Bewegung des Auftragsmediums vom Auftragswerk zum Untergrund hauptsächlich vom Ausstoßimpuls aus der Abgabedüse des Auftragswerks herrührt, grundlegend, da die Gestalt des aus der Abgabedüse austretenden Vorhangs lediglich dem Wechsetspiel zwischen der Oberflächenspannung des Auftragsmediums und der Schwerkraft ausgesetzt ist. Die Oberflächenspannung versucht dabei, den Vorhang, der bezogen auf sein Volumen bzw. seine Querschnittsfläche eine sehr große Oberfläche bzw. Umfangslänge aufweist, zusammenzuziehen, um so seine Oberfläche zu verringern. Diesem Effekt widersetzt sich lediglich die Schwerkraft, die den Vorhang zu strecken sucht. Es ist daher leicht einzusehen, dass es umso schwieriger ist, einen über die gesamte Arbeitsbreite gleichmäßig dicken Auftragsmedium-Vorhang zu erhalten, je größer diese Arbeitsbreite ist.When coating material webs using a curtain applicator (also known as "curtain coating") the application medium to the surface in the form of an application medium curtain issued, which is due to gravity from Commissioned work moved to the underground. That the curtain commission is at a predetermined distance from the surface Among other things, it has the advantage that it breaks down, for example is exposed to a lower risk of damage. Curtain coaters differ from other "contactless" commissions, for example free jet nozzle applicators, in which the movement of the order medium from the order work to the underground mainly comes from the ejection impulse from the delivery nozzle of the application unit, fundamental since the shape of the emerging from the dispensing nozzle Curtain only the interplay between the surface tension of the application medium and gravity. The surface tension tries to make the curtain based on its volume or its cross-sectional area has a very large surface or Has circumferential length to contract so as to its surface reduce. Only gravity opposes this effect Tries to stretch the curtain. It is therefore easy to see that it is all the more it is more difficult to have a uniform thickness across the entire working width Obtain order medium curtain, the larger this working width.

Die Beschichtung von Materialbahnen mittels eines Vorhang-Auftragswerks, das der Materialbahn das Auftragsmedium als sich im Wesentlichen schwerkraftbedingt bewegenden Auftragsmedium-Vorhang bzw. -Schleier zuführt, ist von der Beschichtung von photographischen Filmen, Tonbändern und dergleichen seit langem bekannt. Allerdings weisen die Materialbahnen auf diesen Anwendungsgebieten eine erheblich geringere Breite auf, als dies bei modernen Anlagen zur Herstellung von Papier- und Pappebahnen der Fall ist, bei denen Materialbahnbreiten von mehr als 10 m gefordert werden. Einen über diese Breite gleichmäßig dicken Auftragsmedium-Vorhang bilden und stabil halten zu können, ist eine Aufgabe, bei der es alles andere als naheliegt, sich von den vergleichsweise einfach zu kontrollierenden bekannten schmalen Auftragsmedium-Vorhängen Anregungen für eine funktionstaugliche Lösung zu erwarten. Darüber hinaus bewegen sich die Materialbahnen in modernen Anlagen zur Herstellung von Papier- und Pappebahnen mit Geschwindigkeiten von bis zu 3000 m/min, was ein Vielfaches der Geschwindigkeit ist, mit der sich die bekannten schmalen Materialbahnen bewegen, und überdies eine weitere hohe Belastung für die Stabilität des Auftragsmedium-Vorhangs darstellt.The coating of material webs using a curtain applicator, that the material web the order medium as in the The application medium curtain moves due to gravity or veil is from the coating of photographic Films, tapes and the like have long been known. Indeed the material webs in these areas of application have a significant impact smaller width than that of modern plants for the production of Paper and cardboard webs is the case where material web widths of more than 10 m are required. One even over this width to be able to form a thick application medium curtain and keep it stable a task that is far from obvious to move away from the comparatively easy to control known narrow Application medium curtains suggestions for a functional Expected solution. In addition, the material webs move in modern plants for the production of paper and cardboard webs with Speeds of up to 3000 m / min, which is a multiple of that Is the speed at which the well-known narrow material webs move, and moreover another high burden on the stability of the Order medium curtain represents.

Eine Vorrichtung der eingangs genannten Art ist aus der DE 197 16 466 A1 bekannt. Diese Druckschrift zeigt eine Vorrichtung zum Auftragen von Dispersionen auf eine Materialbahn durch ein sogenanntens Curtain-Coating-Auftragsverfahren. Dabei sind längs der in Materialbahnquerrichtung seitlichen Ränder des sich über die Arbeitsbreite der Vorrichtung erstreckende Auftragsmedium-Vorhangs je ein von einem Auftragswerk zur Materialbahn hin verlaufendes Randführungselement angeordnet, welche je nach Ausführungsform vom Auftragsmedium benetzt sein können oder nicht. Im Fall von benetzten Randführungselementen wird der Auftragsmedium-Vorhang an seinen seitlichen Rändern durch Adhäsionskräfte in Materialbahnquerrichtung gestreckt. Im Falle nicht benetzter Randführungsetemente sind diese als Elektroden ausgebildet, welche ein elektrisches Feld erzeugen, das derart auf die seitlichen Ränder des Auftragsmedium-Vorhangs einwirkt, dass diese in Materialbahnquerrichtung gestreckt wird. Nachteilig an diesem Stand der Technik ist, dass der Auftragsmedium-Vorhang durch die genannte Vorrichtung lediglich an seinen seitlichen Rändern beeinflussbar ist. Dies kann besonders bei großen Arbeitsbreiten zu unbefriedegenden Auftragsergebnissen vor allem in der Arbeitsbreitenmitte führen.A device of the type mentioned is from DE 197 16 466 A1 known. This document shows a device for applying Dispersions on a material web by a so-called curtain coating application process. Along the in Material web cross direction lateral edges of the working width the application medium curtain extending one by one Commissioned edge guide element running towards the material web arranged, depending on the embodiment of the application medium may or may not be wetted. In the case of wetted The order medium curtain will have edge guiding elements on it lateral edges due to adhesive forces in the transverse direction of the material web stretched. In the case of non-wetted edge guide elements, these are as Electrodes formed, which generate an electric field, the such that acts on the side edges of the application medium curtain this is stretched in the transverse direction of the material web. Disadvantage of this State of the art is that the application medium curtain through the mentioned device can only be influenced at its lateral edges is. This can be unsatisfactory, especially with large working widths Maintain order results especially in the middle of the working width.

Die DE 199 03 559 A1 stellt eine ganze Reihe von Wirkprinzipien vor, welche es ermöglichen sollen, die von der Materialbahn mitgeführte Luftgrenzschicht unmittelbar vor einem Vorhang-Auftragswerk zu schwächen. Auf die Möglichkeiten, die Effizienz dieser Wirkprinzipien zu verbessern, geht diese Druckschrift jedoch nicht ein. DE 199 03 559 A1 presents a whole series of active principles, which should make it possible to carry along the material web Air boundary layer immediately in front of a curtain application weaknesses. On the possibilities of the efficiency of these active principles improve, this document is not considered.

Die WO 97/03009 befasst sich mit dem Problem der Trocknung von Materialbahnen nach dem Auftrag von Medien, nämlich Druckfarben, insbesondere im Tief- Rollenoffset- und Flexodruck. Sie schlägt vor, die Gasmoleküle an der Oberfläche der Materialbahn mittels einer KoronaEntladung zu ionisieren und zu einer Elektrode hin zu beschleunigen, um durch den mit diesem "lonenwind" einhergehenden Gasaustausch an der Materialbahnoberfläche die Trocknungseffizienz zu erhöhen.WO 97/03009 deals with the problem of drying Material webs after applying media, namely printing inks, especially in gravure web offset and flexo printing. She suggests that Gas molecules on the surface of the material web by means of a corona discharge to ionize and accelerate towards an electrode to through the gas exchange associated with this "ion wind" at the Material surface to increase the drying efficiency.

Die DE 1 98 03 240 A1 offenbart eine Curtain-Coating-Auftragsvorrichtung, welche eine Sensoreinrichtung zur Erfassung der Strichmenge der auf die Materialbahn aufgetragenen Auftragsmedium-Schicht und eine Regeleinrichtung zur Regelung der Auftragsmenge umfasst. Die Auftragsmenge wird über eine Veränderung der Spaltweite des Auftragsmedium-Austrittsspalts am Auftragswerk geregelt.DE 1 98 03 240 A1 discloses a curtain coating application device, which is a sensor device for detecting the amount of coating on the Application medium layer applied and a layer Control device for regulating the order quantity includes. The Order quantity is determined by changing the gap width of the Order medium outlet gap regulated at the order plant.

Die EP 0 937 815 A1 zeigt eine Vorrichtung zum Auftragen eines flüssigen oder pastösen Auftragsmediums durch einen Auftragsmedium-Strahl, bei welcher der Auftragsbereich durch Blendenelemente vergrößert oder verkleinert werden kann, die von den seitlichen Rändern des Auftragsbereichs her in Materialbahnquerrichtung derart über Auftragsmedium-Düsen bewegt werden können, dass der von diesen ausgehende Auftragsmedium-Strahl von der Blende abgefangen wird und die Materialbahn nicht erreicht.EP 0 937 815 A1 shows a device for applying a liquid or pasty application medium through an application medium jet, at which enlarges the application area by means of aperture elements or can be reduced by the side edges of the Order area forth in the cross direction of the web so Application medium nozzles can be moved, that of these outgoing application medium jet is intercepted by the aperture and the material web has not reached.

Zum weiteren Stand der Technik sei der Vollständigkeit halber noch auf die DE 198 29 449 A1 verwiesen.For the sake of completeness, we refer to the further state of the art DE 198 29 449 A1 referenced.

Demgegenüber ist es Aufgabe der vorliegenden Erfindung, "kontaktlos" arbeitende Auftragsvorrichtungen für den Einsatz in Anlagen zur Herstellung oder/und Veredelung von breiten und sich schnell bewegenden Materialbahnen, vorzugsweise aus Papier oder Karton, weiter zu verbessern, insbesondere was die Stabilisierung des Auftragsmedium-Strahls bzw. -Vorhangs anbelangt.In contrast, it is an object of the present invention to "contactless" working application devices for use in systems for Manufacture or / and finishing of wide and fast moving Material webs, preferably made of paper or cardboard, continue to improve, especially what the stabilization of the application medium jet or curtain.

Diese Aufgabe wird gemäß einem ersten Gesichtspunkt der vorliegenden Erfindung gelöst durch eine Vorrichtung mit den Merkmalen des Anspruchs 1.This task is accomplished according to a first aspect of the present Invention solved by a device with the features of the claim 1.

Das die Schwerkraft bei der Beschleunigung des Auftragsmedium-Strahls unterstützende elektrische Feld wird erfindungsgemäß in einfacher Weise dadurch erzeugt, dass das Auftragswerk auf einem ersten vorbestimmten elektrischen Potential gehalten ist, während der Untergrund auf einem zweiten vorbestimmten elektrischen Potential, beispielsweise Masse- bzw. Erdpotential, gehalten werden kann. In diesem Fall brauchen keine zusätzlichen Elektroden vorgesehen zu werden, sondern es genügt, die vorhandenen Vorrichtungen mit elektrischen Anschlüssen zu versehen.This is the force of gravity when accelerating the application medium jet supporting electric field is inventively in a simple manner generated in that the commissioned work on a first predetermined electrical potential is kept while the underground is on a second predetermined electrical potential, for example ground or Earth potential, can be kept. In this case, no need additional electrodes are to be provided, but it suffices that to provide existing devices with electrical connections.

Im Unterschied zu den vorstehend beschriebenen herkömmlichen "kontaktlosen" Auftragsvorrichtungen, insbesondere Vorhang-Auftragsvorrichtungen, bewegt sich der Auftragsmedium-Strahl bei der erfindungsgemäßen Auftragsvorrichtung nicht allein unter dem Einfluss der Schwerkraft bzw. nicht allein unter dem Einfluss des Ausstoßimpulses von der Abgabedüse zum Untergrund. Vielmehr wird diese Bewegung durch eine zusätzliche Kraft unterstützt, welche von der Felderzeugungsvorrichtung auf den Auftragsmedium-Strahl ausgeübt wird und den Strahl auf seinem Weg von der Abgabedüse zum Untergrund zu strecken sucht (Vorstreckung). Daher kann insbesondere bei "Curtain coating-Auftragswerken" entweder bei gleichem Abstand zwischen Abgabedüse und Untergrund die Stabilität des Strahls erhöht werden, oder der Abstand zwischen Abgabedüse und Untergrund bei vorgegebener gewünschter Strahlstabilität größer gewählt werden. In contrast to the conventional "contactless" described above Application devices, in particular curtain application devices, the application medium jet moves in the case of the invention Application device not only under the influence of gravity or not only under the influence of the ejection pulse from the discharge nozzle to the underground. Rather, this movement is accompanied by an additional one Force supported by the field generating device on the Application medium beam is exerted and the beam on its way from the dispensing nozzle tries to stretch to the surface (pre-stretching). Therefore can be used in particular for "curtain coating commissioned works" equal distance between the dispensing nozzle and the surface the stability of the Jet increased, or the distance between the dispensing nozzle and For a given desired radiation stability, choose a larger surface become.

Insbesondere letzteres ist von Vorteil, wenn man bedenkt, dass sich die Gesamtstreckung des Auftragsmediums von einer durch die Weite der Abgabedüse bestimmten Strahldicke bis zu der Dicke der letztendlich auf den Untergrund aufgebrachten Schicht von Auftragsmedium aus dem Produkt der vorstehend beschriebenen Vorstreckung des Strahls auf dem Weg von der Abgabedüse zum Untergrund und der Kontaktstreckung zusammensetzt, welche vom Unterschied zwischen der Geschwindigkeit des Strahls unmittelbar vor dem Auftreffen auf den Untergrund und der Laufgeschwindigkeit des Untergrunds beim Kontakt des Auftragsmediums mit dem Untergrund herrührt. Für die Erzielung einer möglichst gleichmäßigen Auftragsschicht ist es nämlich von Vorteil, wenn sich die Gesamtstreckung möglichst gleichmäßig aus Vorstreckung und Kontaktstreckung zusammensetzt. Da der Auftragsmedium-Strahl umso anfälliger für äußere Einflüsse ist, beispielsweise für den Einfluss der vom Untergrund mitgeführten Luftgrenzschicht, je länger der Weg des Auftragsmediums von der Abgabedüse zum Untergrund ist, läuft dies in der Praxis stets auf den Wunsch nach einer möglichst starken Vorstreckung hinaus.The latter is particularly advantageous when you consider that the Total stretch of the application medium from one to the other Dispensing nozzle determines the jet thickness up to the thickness of the ultimately the substrate applied layer of application medium from the Product of the beam stretching on the beam described above Away from the dispensing nozzle to the surface and the contact extension composed of the difference between the speed the beam immediately before it hits the ground and the Running speed of the surface when the application medium comes into contact comes from the underground. To achieve the most even possible It is an advantage of the order layer if the Total stretching as evenly as possible from pre-stretching and contact stretching composed. Because the application medium jet is all the more vulnerable for external influences, for example for the influence of the underground air boundary layer, the longer the path of the application medium from the discharge nozzle to the surface, this always runs in practice on the Desire for the strongest possible advance.

Darüber hinaus wird aber von dem elektrischen Feld auf den Auftragsmedium-Strahl auch eine Kraft ausgeübt, die eine orthogonal zu dessen Bewegungsrichtung verlaufende Komponente besitzt, d.h. die Elektrodenanordnung zieht den Auftragsmedium-Strahl an. Auch diese Kraftkomponente hilft, den Auftragsmedium-Strahl gegenüber dem Einfluss der an der Oberfläche des Untergrunds mitgeführten Luftgrenzschicht zu stabilisieren.In addition, however, the electric field on the Application medium jet also exerted a force that is orthogonal to one whose direction of movement has a running component, i.e. the Electrode arrangement attracts the application medium jet. This too Force component helps the application medium jet against the influence the air boundary layer carried on the surface of the subsurface stabilize.

Zusätzlich oder alternativ kann jedoch auf der stromaufwärtigen Seite des Auftragswerks und in dessen Nachbarschaft eine Elektrodenanordnung vorgesehen sein, welche auf einem vorbestimmten elektrischen Elektrodenanordnungs-Potential gehalten ist. "Zusätzlich" bedeutet dabei, dass sowohl das Auftragswerk als auch die Elektrodenanordnung auf einem vorbestimmten, vom Erdpotential verschiedenen Potential gehalten sind. Additionally or alternatively, however, on the upstream side of the Commissioned work and in its vicinity an electrode arrangement be provided which on a predetermined electrical Electrode arrangement potential is kept. "Additional" means that both the application and the electrode arrangement on one predetermined potential different from the earth potential.

Hingegen bedeutet "alternativ", dass nur die Elektrodenanordnung auf einem vorbestimmten, vom Erdpotential verschiedenen Potential gehalten sind, während das Auftragswerk entweder geerdet ist oder sich hinsichtlich seines elektrischen Potentials in der Schwebe befindet ("floating potential").In contrast, "alternative" means that only the electrode arrangement is on a predetermined potential different from the earth potential are while the work is either grounded or its electrical potential is in suspension ("floating potential").

Die Aufgabe der vorliegenden Erfindung wird gemäß einem zweiten Gesichtspunkt der Erfindung durch die gerade beschriebene "alternative" Bereitstellung einer Elektrodenanordnung, nämlich durch eine Auftragsvorrichtung mit den Merkmalen des Anspruchs 5 gelöst.The object of the present invention is achieved according to a second Aspect of the invention by the "alternative" just described Provision of an electrode arrangement, namely by a Application device with the features of claim 5 solved.

Die Elektrodenanordnung kann wenigstens eine Flachelektrode umfassen. Dabei kann die Flachelektrode an ihrer zum Untergrund hinweisenden Seite eine Mehrzahl von Vorsprüngen oder Nadelspitzen aufweisen. Alternativ ist es jedoch auch möglich, dass die Elektrodenanordnung eine Mehrzahl von in Querrichtung des Untergrundes einander benachbart angeordneten Einzetelektroden, vorzugsweise Nadelelektroden, umfasst. Durch den Einsatz von Nadelspitzen bzw. Nadelelektroden kann erreicht werden, dass die Elektrodenanordnung ihre Umgebung nicht nur durch das bezüglich dem Erdpotential gebildete elektrische Feld beeinflusst, sondern dass es darüber hinaus auch zu Entladungsvorgängen kommen kann, bei welchen die Umgebungsluft zumindest teilweise ionisiert wird, und die so entstandenen Ladungsträger zu einer Aufladung beispielsweise des Auftragsmedium-Strahls führen. Nach einer derartigen Aufladung kann die Bewegung des Auftragsmedium-Strahls noch effektiver durch das elektrische Feld beeinflusst werden.The electrode arrangement can comprise at least one flat electrode. The flat electrode can be on its side facing the surface have a plurality of protrusions or needle tips. Alternative is however, it is also possible for the electrode arrangement to have a plurality of arranged adjacent to one another in the transverse direction of the substrate Single electrodes, preferably needle electrodes. By the The use of needle tips or needle electrodes can achieve that the electrode arrangement does not only reflect its surroundings by that Earth potential formed electric field, but that it affects above discharge processes may also occur, in which the Ambient air is at least partially ionized, and the resulting Charge carriers for charging the application medium jet, for example to lead. After such charging, the movement of the Application medium beam even more effectively through the electric field to be influenced.

In Weiterbildung der Erfindung wird vorgeschlagen, dass stromabwärts der Auftreffposition des Auftragsmediums auf den Untergrund eine Vorrichtung zum Erzeugen eines elektrischen Feldes vorgesehen ist. Dieses elektrische Feld übt auf das auf den Untergrund aufgebrachte Auftragsmedium eine zum Untergrund hin gerichtete Kraft aus, was an Stellen, auf die zuviel Auftragsmedium aufgebracht worden ist, zu einer Verdrängung des überschüssigen Auftragsmediums führt. Hierdurch wird zum einen auch bislang nicht bedeckten Stellen des Untergrunds Auftragsmedium zugeführt, was die Bedeckung des Untergrunds mit Auftragsmedium verbessert. Zum anderen kann hierdurch die Dicke der Auftragsschicht vergleichmäßigt werden.In a further development of the invention it is proposed that the A device strikes the position of the application medium on the substrate is provided for generating an electric field. This electrical Field exercises a on the application medium applied to the surface force directed towards the underground, what in places, too much Application medium has been applied to displace the excess Order medium leads. On the one hand, this means that so far uncovered areas of the substrate application medium supplied what improved coverage of the substrate with application medium. To the others can hereby even out the thickness of the application layer become.

Bevorzugt weist die weitere Felderzeugungsvorrichtung eine dem Untergrund benachbarte weitere Elektrodenanordnung auf, welche vorzugsweise auf einem weiteren vorbestimmten elektrischen Potential gehalten ist.The further field generating device preferably has one Background adjacent further electrode arrangement, which preferably at a further predetermined electrical potential is held.

Eine derartige, das auf den Untergrund aufgebrachte Auftragsmedium zum Untergrund hin ziehende Kraft kann grundsätzlich aber auch von einer Restaufladung des auf den Untergrund aufgebrachten Auftragsmediums infolge von durch die erste Elektrodenanordung induzierten Entladungen herrühren.Such an application medium applied to the substrate Basically, pulling force can also come from one Residual charging of the application medium applied to the surface as a result of discharges induced by the first electrode arrangement originate.

Das bzw. die vom Erdpotential verschiedenen, vorbestimmten elektrischen Potentiale können beispielsweise einen Wert von zwischen 5 kV und etwa 60 kV, vorzugsweise etwa 30 kV aufweisen.That or the predetermined electrical different from the earth potential Potentials can have a value of between 5 kV and approximately, for example 60 kV, preferably about 30 kV.

Wie vorstehend bereits erwähnt, wird der Untergrund vorzugsweise auf Erdpotential gehalten. Dies kann beispielsweise dadurch realisiert werden, dass ein Gegenelement, vorzugsweise eine Gegenwalze, das bei direktem Auftrag die Materialbahn im Bereich des Auftragswerks stützt bzw. auf dessen Oberfläche das Auftragswerk das Auftragsmedium bei indirektem Auftrag aufbringt, mit einer Elektrode in Kontakt steht, um diese auf dem zweiten vorbestimmten elektrischen Potential zu halten. Zusätzlich oder alternativ kann jedoch auch vorgesehen sein, dass die, beispielsweise metallische oder gummierte, Oberfläche des Gegenelements mit der Elektrode in Schleifkontakt steht. Schließlich ist es auch noch möglich, dass die Elektrode mit einer Lagerwelle der Gegenwalze in elektrisch leitendem Kontakt steht. Bei direktem Auftrag kommt als weitere Alternative hinzu, dass man die Materialbahn mittels einer beispielsweise als Bahnleitelement ausgebildeten Elektrode auf dem zweiten vorbestimmten elektrischen Potential, also vorzugsweise dem Erdpotential, hält.As already mentioned above, the subsurface is preferably on Earth potential held. This can be achieved, for example, by that a counter element, preferably a counter roller, which with direct Order supports or supports the material web in the area of the order plant whose surface the application work the application medium with indirect Application, is in contact with an electrode to place it on the to hold the second predetermined electrical potential. In addition or alternatively, however, it can also be provided that the, for example metallic or rubberized, surface of the counter element with the electrode is in sliding contact. Finally, it is also possible that the Electrode with a bearing shaft of the counter roller in an electrically conductive Contact is there. For direct orders, there is another alternative, that the material web is used, for example, as a web guiding element trained electrode on the second predetermined electrical Potential, so preferably the earth potential.

Neben dem Einsatz von elektrischen Feldern zur Beeinflussung des Auftragsmedium-Strahls kommen selbstverständlich auch anders geartete Kraftfelder in Frage, beispielsweise Magnetfelder, sofern das Auftragsmedium auf ein Magnetfeld ansprechende Partikel ohnehin als Bestandteil enthält oder diese Partikel dem Auftragsmedium zu diesem Zweck beigemengt werden können.In addition to the use of electrical fields to influence the Of course, the application medium jet also comes in a different way Force fields in question, for example magnetic fields, if that Application medium as a particle responding to a magnetic field anyway Contains component or these particles the application medium to this Purpose can be added.

Um den Einfluss der an der Oberfläche des Untergrunds mitgeführten Luftgrenzschicht auf den Auftragsmedium-Strahl gering halten zu können, wird vorgeschlagen, dass der Elektrodenanordnung in Laufrichtung des Untergrundes eine Vorrichtung zur Schwächung der von dem Untergrund mitgeführten Luftgrenzschicht vorgeordnet ist. Dabei kann die Luftgrenzschicht-Schwächungsvorrichtung eine Absaugvorrichtung umfassen, mit deren Hilfe die Luftgrenzschicht aktiv vom laufenden Untergrund entfernt werden kann.The influence of the air boundary layer carried on the surface of the subsurface to be able to keep the application medium jet low proposed that the electrode arrangement in the running direction of the Underground a device for weakening the surface is carried upstream air boundary layer. The Air boundary layer weakening device a suction device include, with the help of the air boundary layer actively from the current Can be removed.

Beispielsweise kann am stromabwärtigen Ende der Absaugvorrichtung ein mit dem Untergrund in Schleifkontakt stehender Schleppschaber vorgesehen sein. Dieser Schleppschaber dichtet die Absaugvorrichtung zur Umgebung hin ab und behindert die Weiterbewegung der Luftgrenzschicht zum Auftragswerk hin. Hierdurch wird die in der Luftgrenzschicht mitgeführte Luft aufgestaut, was den laminaren Charakter der Strömung der Luftgrenzschicht zumindest teilweise zerstört. Dies erleichtert das Absaugen und erhöht die Saugeffizienz der Absaugvorrichtung. Somit kann die Luftgrenzschicht durch die erfindungsgemäß ausgebildete Absaugvorrichtung besonders wirksam geschwächt, wenn nicht gar vollständig vom Untergrund entfernt werden.For example, at the downstream end of the suction device Drag scraper in contact with the ground be provided. This drag scraper seals the suction device Environment and hinders the further movement of the air boundary layer to the commissioned work. As a result, the in the air boundary layer entrained air pent-up what the laminar character of the flow the air boundary layer at least partially destroyed. This makes it easier Suction and increases the suction efficiency of the suction device. So can the air boundary layer through the one designed according to the invention Suction device weakened particularly effectively, if not completely be removed from the ground.

Der Schleppschaber kann als flexible Folie, vorzugsweise aus Kunststoff, Metallblech oder einem Verbundwerkstoff, ausgebildet sein. Die flexible Folie schmiegt sich unter der Saugwirkung der Absaugvorrichtung gegen den Untergrund an, was zum einen die Abdichtung verbessert und zum anderen dem Aufbau einer neuen Luftgrenzschicht vorbeugt. Ist der Schleppschaber aus Metallblech gefertigt, so wird vorzugsweise Edelstahlblech mit einer Dicke von höchstens 0,1 mm eingesetzt. Als vorteilhaft haben sich aber auch Schleppschaber aus Verbundwerkstoff mit einer Oberflächenbeschichtung aus Teflon erwiesen. Der Verbundwerkstoff sorgt dabei für die erforderliche Temperaturbeständigkeit und Flexibilität, während die Oberflächenbeschichtung aus Teflon für eine geringe Reibung zwischen dem Schleppschaber und dem laufenden Untergrund sorgt. Ferner kann der Schleppschaber in Laufrichtung gekrümmt sein, was das elastische Ausweichen erleichtert und die Reibung mit dem Untergrund weiter mindert.The drag scraper can be a flexible film, preferably made of plastic, Metal sheet or a composite material may be formed. The flexible Foil nestles against the suction of the suction device the underground, which improves the sealing on the one hand and prevents others from building a new air boundary layer. Is the Drag scraper made of sheet metal, preferably stainless steel sheet with a thickness of at most 0.1 mm. As beneficial have also scrapers made of composite material with a Surface coating made of Teflon proven. The composite material ensures thereby for the required temperature resistance and flexibility, while the Teflon surface coating for low friction between the drag scraper and the running surface. Furthermore, the drag scraper can be curved in the running direction, which is the elastic dodging eases and friction with the ground further diminishes.

In Weiterbildung der Erfindung wird vorgeschlagen, dass im Bereich der Absaugvorrichtung, vorzugsweise zwischen dem stromabwärtigen Ende der Absaugvorrichtung und dem Schleppschaber, eine weitere Elektrodenanordnung vorgesehen ist. Auch mit Hilfe dieser weiteren Elektrodenanordnung kann die vom Untergrund mitgeführte Luftgrenzschicht beeinflusst und insbesondere geschwächt werden. Vor allem wenn die weitere Elektrodenanordnung eine Mehrzahl von in Querrichtung des Untergrundes einander benachbart angeordneten Einzelelektroden, vorzugsweise Nadelelektroden, umfasst, oder wenn die weitere Elektrodenanordnung wenigstens eine Flachelektrode umfasst, welche an ihrer zum Untergrund hin weisenden Seite eine Mehrzahl von Vorsprüngen oder Nadelspitzen aufweist, kann es zwischen den Spitzen der weiteren Elektrodenanordnung und dem Untergrund ebenfalls zu Entladungsvorgängen kommen. Diese Entladungen stören die laminare Störung der Luftgrenzschicht und wandeln diese zumindest teilweise in eine turbulente Strömung um, was das Absaugen der Luftgrenzschicht erleichtert und somit die Effektivität der Absaugvorrichtung weiter verbessert. Zur Unterstützung des Entstehens dieser Entladungen wird vorgeschlagen, dass die weitere Elektrodenanordnung von dem Untergrund einen Abstand von zwischen etwa 2 mm und etwa 30 mm aufweist.In a development of the invention it is proposed that in the area of Suction device, preferably between the downstream end of the Suction device and the scraper, another electrode arrangement is provided. Also with the help of this further electrode arrangement can affect the air boundary layer carried by the subsurface and especially weakened. Especially when the further electrode arrangement a plurality of each other in the transverse direction of the substrate adjacent individual electrodes, preferably needle electrodes, comprises, or if the further electrode arrangement at least one Includes flat electrode, which on their pointing towards the surface Side has a plurality of projections or needle tips, it can between the tips of the further electrode arrangement and the substrate discharge processes also occur. These discharges disrupt and convert the laminar disturbance of the air boundary layer at least partially into a turbulent flow, which is the suction the air boundary layer and thus the effectiveness of the Suction device further improved. To support the emergence of these discharges it is proposed that the further Electrode arrangement from the substrate a distance of between about 2 mm and about 30 mm.

Die weitere Elektrodenanordnung kann grundsätzlich an eine äußere Spannungsversorgung angeschlossen sein. Es ist jedoch ebenso möglich, und konstruktiv sogar einfacher zu realisieren, wenn das elektrische Potential der weiteren Elektrodenanordnung in der Schwebe gehalten ist ("floating potential"). In diesem Fall wird die weitere Elektrodenanordnung infolge der von der ersten Elektrodenanordnung ausgehenden Entladungen aufgeladen und somit ebenfalls auf ein vom Massepotential verschiedenes Potential gebracht. Zur Reduzierung der Kapazität der weiteren Elektrodenanordnung sowie aus Sicherheitsgründen wird vorgeschlagen, dass die weitere Elektrodenanordnung an der Absaugvorrichtung von dieser elektrisch isoliert angeordnet ist.The further electrode arrangement can in principle be connected to an external one Power supply must be connected. However, it is also possible and constructively even easier to implement if the electrical Potential of the further electrode arrangement is kept in suspense ("floating potential"). In this case, the further electrode arrangement due to the discharges emanating from the first electrode arrangement charged and thus also to a different from the ground potential Brought potential. To reduce the capacity of the further electrode arrangement and for security reasons, it is proposed that the further electrode arrangement on the suction device of this electrically is arranged in isolation.

Wie vorstehend bereits erläutert, versucht die Oberflächenspannung des Auftragsmediums, die Oberfläche des Auftragmedium-Strahls zu verkleinern, was sich insbesondere im Bereich der Seitenränder des Auftragmedium-Strahls auswirkt und zu einer Strahleinengung führt. Dieser Strahleinengung kann durch das Vorsehen von Randführungselementen vorgebeugt werden, da in diesem Fall zwischen dem Auftragsmedium und der Oberfläche der Randführungselemente zusätzlich Adhäsionskräfte wirken, welche sich der von der Oberflächenspannung des Auftragsmediums ausgehenden Einengungstendenz widersetzen.As already explained above, the surface tension of the Application medium, the surface of the application medium jet too reduce what is particularly in the area of the side edges of the Application medium jet affects and leads to a beam narrowing. This The beam can be narrowed by providing edge guide elements be prevented, since in this case between the order medium and additional adhesion forces on the surface of the edge guide elements act which of the surface tension of the Contradict the outgoing narrowing tendency.

Gemäß einem weiteren Gesichtspunkt wird die erfindungsgemäße Aufgabe daher durch eine Vorrichtung mit den Merkmalen des Anspruchs 27 gelöst. According to a further aspect, the object of the invention therefore solved by a device with the features of claim 27.

Aus Gründen einer guten Benetzung der Randführungselemente weisen diese eine strukturierte Oberfläche auf. Hierzu ist erfindungsgemäß die Oberfläche wenigstens eines Randführungselements aufgerauht oder/und weist eine gezahnte Oberfläche, beispielsweise in Form eines Außengewindes oder auch eines Innengewindes, auf.Point for good wetting of the edge guide elements this has a structured surface. For this purpose, according to the invention Surface of at least one edge guide element roughened and / or has a toothed surface, for example in the form of a External thread or an internal thread.

Die Adhäsion zwischen den Randführungselementen und dem Auftragsmedium kann dadurch verbessert werden, dass die Oberflächeneigenschaften wenigstens eines Randführungselements derart gewählt sind, dass der von den Eigenschaften des Auftragsmediums und der Oberfläche der Randführungselemente abhängige Benetzungs- oder Randwinkel weniger als 90° beträgt.The adhesion between the edge guide elements and the Application medium can be improved in that the Surface properties of at least one edge guide element are chosen so that the properties of the application medium and dependent on the surface of the edge guide elements Contact angle is less than 90 °.

Die Randführungselemente können beispielsweise aus Glas oder Metall gefertigt sein, da diese Materialien eine ausreichend hohe Oberflächenspannung aufweisen. Bei Metallen ist allerdings zu beachten, dass einige Metalle die Tendenz haben, Wasserdampf aus der sie umgebenden Atmosphäre zu adsorbieren, wodurch ihre Oberflächenspannung auf den Wert der adsorbierten Wasserschicht sinkt.The edge guide elements can be made of glass or metal, for example be made because these materials have a sufficiently high surface tension exhibit. With metals, however, it should be noted that some Metals tend to get water vapor from the atmosphere surrounding them to adsorb, causing their surface tension to increase in value the adsorbed water layer sinks.

Um die Auftragsvorrichtung an die Breite der zu beschichtenden Materialbahn anpassen zu können, wird vorgeschlagen, dass wenigstens ein Randführungselement in Querrichtung des Untergrunds verschiebbar angeordnet ist oder/und dass der Winkel, den ein Randführungselement mit der Vertikalen einschließt, verstellbar ist. Darüber hinaus kann die Winkelverstellbarkeit ein Verschwenken der freien Enden der Randführungselemente in Querrichtung oder/und in Längsrichtung beinhalten.To apply the applicator to the width of the material web to be coated To be able to adapt, it is proposed that at least one edge guide element slidably arranged in the transverse direction of the substrate is and / or that the angle that an edge guide element with the Includes vertical, is adjustable. In addition, the Angular adjustability a pivoting of the free ends of the edge guide elements in the transverse direction and / or in the longitudinal direction.

Schließlich kann die Wirkung der Randführungselemente auch durch das Vorsehen eines elektrischen Feldes verbessert werden, beispielsweise dadurch, dass in der Nähe wenigstens eines der Randführungselemente, vorzugsweise im Wesentlichen parallel zu diesem verlaufend, eine Elektrode vorgesehen ist, die auf einem vorbestimmten elektrischen Potential gehalten ist.Finally, the effect of the edge guide elements can also by Providing an electric field can be improved, for example in that near at least one of the edge guide elements, preferably running essentially parallel to this, an electrode is provided, which is at a predetermined electrical potential is held.

Die vorstehend genannte Aufgabe wird schließlich durch ein Verfahren mit den Merkmalen des Anspruchs 34 gelöst.The above task is finally accomplished using a method solved the features of claim 34.

Die Erfindung wird im Folgenden an einem Ausführungsbeispiel anhand der beigefügten Zeichnung näher erläutert werden. Es stellt dar:

Fig. 1
eine grob schematische Seitenansicht zur Erläuterung von Aufbau und Funktion einer erfindungsgemäßen Auftragsvorrichtung;
Fig. 2
eine schematische Ansicht zur Erläuterung von Aufbau und Funktion der Randführungselemente; und
Fig. 3
eine Darstellung zur Erläuterung des Begriff "Benetzungswinkel" bzw. "Randwinkel".
The invention will be explained in more detail below using an exemplary embodiment with reference to the accompanying drawing. It shows:
Fig. 1
a rough schematic side view to explain the structure and function of an application device according to the invention;
Fig. 2
a schematic view for explaining the structure and function of the edge guide elements; and
Fig. 3
a representation for explaining the term "wetting angle" or "contact angle".

In Fig. 1 ist eine erfindungsgemäße Auftragsvorrichtung allgemein mit 10 bezeichnet. Sie umfasst ein Vorhang-Auftragswerk 12 mit einer Abgabedüse 14, aus der Auftragsmedium 16 in Form eines Vorhangs 18 an einen sich in Laufrichtung L bewegenden Untergrund U abgegeben wird. Der Untergrund U ist im dargestellten Ausführungsbeispiel die Oberfläche 20a einer Materialbahn 20, die im Bereich des Auftragswerks 12 die Umfangsflächen einer Stützwalze 22 teilweise umschlingt. 1, an application device according to the invention is generally at 10 designated. It comprises a curtain application unit 12 with a Dispensing nozzle 14, from the application medium 16 in the form of a curtain 18th is delivered to a substrate U moving in the direction of travel L. In the exemplary embodiment shown, the subsurface U is the surface 20a of a material web 20, which in the area of the application unit 12 Circumferential surfaces of a support roller 22 partially wrapped.

Auf seinem Weg von der Abgabedüse 14 zum Untergrund U wird das Auftragsmedium 16 beschleunigt. Dies führt zu einer Verringerung der Dicke des Vorhangs 18 von dem Wert D im Bereich der Abgabedüse 14 auf den Wert d unmittelbar vor der Auftreffpositon P auf dem Untergrund U (Vorstreckung). Infolge des Unterschieds zwischen der Geschwindigkeit des Auftragmedium-Vorhangs 18 unmittelbar vor der Auftreffposition P und der Laufgeschwindigkeit des Untergrunds U wird das Auftragsmedium 16 beim Auftreffen auf dem Untergrund U nochmals gestreckt, so dass die auf den Untergrund U aufgebrachte Auftragsschicht 24 letztendlich die Dicke s aufweist (Kontaktstreckung). Die Gesamtstreckung des Auftragsmedium 16 ergibt als Produkt der Streckungsfaktoren von Vorstreckung und Kontaktstreckung.On its way from the dispensing nozzle 14 to the substrate U, the application medium 16 accelerated. This leads to a reduction in thickness of the curtain 18 from the value D in the region of the dispensing nozzle 14 to the Value d immediately before the impact position P on the underground U (Pre-stretching). Due to the difference between the speeds the application medium curtain 18 immediately before the impact position P and The application medium 16 becomes the running speed of the underground U stretched again when hitting the underground U, so that the on the application layer 24 applied to the substrate U ultimately the thickness s has (contact extension). The total stretch of the order medium 16 is the product of the stretching factors of pre-stretching and Contact extension.

In der Praxis wird das Auftragsmedium 16 beim Auftreffen auf den Untergrund U meist stärker gestreckt als auf dem Weg von der Abgabedüse 14 zum Untergrund U, da man im Hinblick auf einen möglichst stabilen Vorhang 18 die Fallstrecke zwischen Abgabedüse 14 und Untergrund U nicht beliebig groß wählen kann. Eine zu starke Kontaktstreckung wirkt sich aber nachteilig auf die Gleichmäßigkeit der auf den Untergrund U aufgebrachten Auftragsschicht 24 aus.In practice, the application medium 16 becomes when it hits the surface U usually stretched more than on the way from the dispensing nozzle 14 to the underground U, since one is as stable as possible Curtain 18 the distance between the dispensing nozzle 14 and the underground U cannot choose any size. Too much contact extension works but adversely affect the uniformity of the underground U applied application layer 24.

Die erfindungsgemäße Auftragsvorrichtung 10 bietet nun eine Möglichkeit, mit deren Hilfe man entweder bei gleicher Fallhöhe zwischen Abgabedüse 14 und Untergrund U die Vorstreckung des Vorhangs 18 verstärken kann bzw. wie man bei gleicher Vorstreckung die Fallhöhe zwischen Abgabedüse 14 und Untergrund U verringern und somit den Vorhang 18 stabilisieren kann. Und zwar wird erfindungsgemäß der Auftragmedium-Vorhang 18 auf seinem Weg von der Abgabedüse 14 zum Untergrund U nicht allein der Schwerkraft überlassen, sondern es werden auf ihn zusätzlich elektrostatische Kräfte ausgeübt. Diese Stärkung der den Vorhang 18 streckenden Kräfte hat, da die Oberflächenspannung des Auftragsmediums 16, die den Vorhang 18 im Sinne einer Verringerung von dessen Oberfläche zusammenzuziehen sucht, konstant bleibt, eine höhere Stabilität des Auftragmedium-Vorhang 18 zur Folge.The application device 10 according to the invention now offers a possibility with the help of which one either has the same head between the dispensing nozzle 14 and underground U can intensify the pre-stretching of the curtain 18 or how to drop the height between the dispensing nozzle with the same pre-stretching 14 and reduce underground U and thus stabilize the curtain 18 can. According to the invention, the application medium curtain 18 is opened its way from the dispensing nozzle 14 to the underground U not only the Gravity left, but there will be additional electrostatic on it Powers exercised. This strengthening of the curtain 18 stretching Has forces, since the surface tension of the application medium 16, the Curtain 18 in the sense of reducing its surface tries to contract, remains constant, a higher stability of the Application medium curtain 18 result.

Grundsätzlich könnten die elektrostatischen Kräfte dadurch bereitgestellt werden, dass man an das Gehäuse des Auftragswerks 12 eine erste vorbestimmte elektrische Spannung V1 anlegt und die Stützwalze 22 auf demIn principle, the electrostatic forces could be provided by applying a first predetermined electrical voltage V 1 to the housing of the application unit 12 and the support roller 22 on the

Erd- bzw. Massepotential VE bzw. V2 hält. In dem Ausführungsbeispiel gemäß Fig. 1 wird jedoch ein anderer Weg beschritten, der nachfolgend näher erläutert werden soll:Earth or ground potential V E or V 2 holds. In the exemplary embodiment according to FIG. 1, however, a different path is followed, which will be explained in more detail below:

Gemäß Fig. 1 ist in Laufrichtung L unmittelbar vor dem Auftragswerk 12 eine Elektrodenanordnung 30 vorgesehen, die beispielsweise eine sich in Querrichtung Q erstreckende Flachelektrode mit einer Mehrzahl von Nadelspitzen umfassen kann, oder von einer Mehrzahl von in Querrichtung Q einander benachbart angeordneten Nadelelektroden 32 gebildet sein kann. An die Elektrodenanordnung 30 wird eine vorbestimmte elektrische Spannung V3 angelegt, während die sie umgebenden Teile der Auftragsvorrichtung 10, nämlich das Auftragswerk 12, die Stützwalze 22 und ein bezüglich der Laufrichtung L stromaufwärts der Elektrodenanordnung 30 vorgesehener Saugkasten 34 zur Schwächung einer von der Materialbahn 20 mitgeführten Luftgrenzschicht auf Masse- bzw. Erdpotential VE gehalten sind.According to FIG. 1, an electrode arrangement 30 is provided in the running direction L directly in front of the application unit 12, which can for example comprise a flat electrode extending in the transverse direction Q with a plurality of needle tips, or formed by a plurality of needle electrodes 32 arranged adjacent to one another in the transverse direction Q. can. A predetermined electrical voltage V 3 is applied to the electrode arrangement 30, while the parts of the application device 10 surrounding it, namely the application unit 12, the support roller 22 and a suction box 34 provided upstream of the electrode arrangement 30 with respect to the running direction L for weakening a material web 20 entrained air boundary layer are kept at ground or earth potential V E.

Zwischen der Elektrodenanordnung 30 und ihrer auf Erdpotential gehaltenen Umgebung baut sich nicht nur ein elektrisches Feld auf, sondern es kommt zwischen den Nadelspitzen bzw. Nadelelektroden 32 und der Umgebung zu Entladungen, die in Fig. 1 durch die gestrichelten Linien E angedeutet sind. Infolge dieser Entladungen E wird das Auftragsmedium 16 des Vorhangs 18 elektrisch aufgeladen, so dass es in dem elektrischen Feld zwischen der Elektrodenanordnung 30 und der Stützwalze 22 zur Stützwalze 22 hin beschleunigt wird, was die Vorstreckung unterstützt. Between the electrode arrangement 30 and its at ground potential environment, not only does an electric field build up, instead it comes between the needle tips or needle electrodes 32 and the environment to discharges, which are shown in Fig. 1 by the dashed lines Lines E are indicated. As a result of these discharges E, the Application medium 16 of the curtain 18 electrically charged so that it is in the electric field between the electrode arrangement 30 and the Back-up roller 22 to the back-up roller 22 is accelerated, which is the Advancement supported.

Darüber hinaus wird auf den Vorhang 18 infolge der Entladungen E aber auch eine Kraft ausgeübt, die eine orthogonal zu dessen Fallbewegungsrichtung verlaufende Komponente besitzt. Auch diese Kraftkomponente hilft, den Auftragsmedium-Vorhang 18 vor dem Einfluss der an der Oberfläche der Materialbahn 20 mitgeführten Luftgrenzschicht G zu stabilisieren.In addition, the curtain 18 due to the discharges E, however also exerted a force that is orthogonal to the direction of its fall running component. This force component too helps to remove the application medium curtain 18 from the influence of the Surface of the material web 20 entrained air boundary layer G to stabilize.

Wie vorstehend bereits angesprochen, dient der Saugkasten 34 zur Schwächung der Luftgrenzschicht G. Zur Erhöhung der Saugeffizienz ist an diesem Saugkasten 34 auslaufseitig ein Schleppschaber 36 vorgesehen, der mit der Oberfläche 20a der Materialbahn 20 in Gleitkontakt steht und den Saugbereich des Saugkastens 34 auslaufseitig abdichtet. Der Schleppschaber 36 kann beispielsweise aus einem mit Teflon beschichteten Verbundwerkstoff gefertigt sein. Aufgrund des Einsatzes eines Verbundwerkstoffs weist der Schleppschaber 36 ausreichende Temperaturbeständigkeit und Flexibilität, und aufgrund der Oberflächenbeschichtung mit Teflon ausreichende Reibungsarmut auf.As already mentioned above, the suction box 34 is used for Weakening of the air boundary layer G. To increase the suction efficiency is on a drag scraper 36 is provided on the outlet side of this suction box 34, which is in sliding contact with the surface 20a of the material web 20 and seals the suction area of the suction box 34 on the outlet side. The drag scraper 36 can, for example, be made of a Teflon-coated material Be made of composite material. Due to the use of a composite material the drag scraper 36 has sufficient temperature resistance and flexibility, and because of the surface coating sufficient friction with Teflon.

Erfindungsgemäß ist nun zwischen diesem Schleppschaber 36 und dem Saugkasten 34 eine weitere Elektrodenanordnung 40 vorgesehen, die an dem Saugkasten 34 über eine elektrischen Isolierung 42 angebracht ist. Die weitere Elektrodenanordnung 40 kann wiederum entweder von einer Flachelektrode mit einer Mehrzahl von Nadelspitzen oder einer Mehrzahl von in Querrichtung Q einander benachbart angeordneten Nadelelektroden gebildet sein. Die Elektrodenanordnung 40 kann grundsätzlich an eine äußere Spannungsversorgung angeschlossen sein. In dem dargestellten Ausführungsbeispiel befindet sie sich hinsichtlich ihres elektrischen Potentials jedoch in einem Schwebezustand ("floating potential"), wird aber infolge der von der Elektrodenanordnung 30 ausgehenden Entladungen E aufgeladen und somit ebenfalls auf ein vom Massepotential verschiedenes Potential gebracht. According to the invention is now between this scraper 36 and the A further electrode arrangement 40 is provided on the suction box 34 the suction box 34 is attached via electrical insulation 42. The further electrode arrangement 40 can either be from a flat electrode with a plurality of needle tips or a plurality of in Transverse direction Q needle electrodes arranged adjacent to each other be educated. In principle, the electrode arrangement 40 can be connected to a external power supply must be connected. In the illustrated Embodiment is in terms of its electrical Potentials, however, in a floating state ("floating potential"), however as a result of the discharges E charged and thus also to a different from the ground potential Brought potential.

Aufgrund des geringen Abstands der Spitzen der Elektrodenanordnung 40 vom Untergrund U genügt die Aufladung der Elektrodenanordnung 40, um es zwischen den Spitzen der Elektrodenanordnung 40 und dem Untergrund U ebenfalls zu Entladungen e kommen zu lassen. Diese Entladungen e stören die laminare Strömung der Luftgrenzschicht G und wandeln diese zumindest teilweise in eine turbulente Strömung um. Dies erleichtert das Absaugen der Luftgrenzschicht G von der Oberfläche 20a der Materialbahn und verbessert somit die Effektivität des Saugkastens 34.Due to the small distance between the tips of the electrode arrangement 40 from the underground U, the charge of the electrode arrangement 40 is sufficient to it between the tips of the electrode assembly 40 and the ground U also allow discharges to occur. These discharges e disrupt the laminar flow of the air boundary layer G and convert it at least partially into a turbulent flow. This makes it easier Aspirating the air boundary layer G from the surface 20a of the material web and thus improves the effectiveness of the suction box 34.

Elektrische Kräfte können schließlich auch noch zur Verbesserung der Egalisierung und Fixierung der Auftragsschicht 24 auf der Materialbahn 20 beitragen. Hierzu kann beispielsweise eine weitere Elektrodenanordnung in Form einer Plattenelektrode 46 vorgesehen sein, die auf einem vorbestimmten elektrischen Potential V4 gehalten ist. Zwischen dieser Plattenelektrode 46 und der auf Massepotential gehaltenen Stützwalze 22 bildet sich ein relativ homogenes elektrisches Feld aus, welches auf das Auftragsmedium eine zum Untergrund U hin gerichtete Kraft ausübt. Diese Kraft sorgt an Stellen der Materialbahnoberfläche 20a, auf die zuviel Auftragsmedium 16 aufgetragen worden ist, zu einer Verdrängung des überschüssigen Auftragsmediums und somit zu einer Vergleichmäßigung der Auftragsschicht 24. Im Extremfall kann es sogar vorkommen, dass bislang nicht bedeckte Bereiche der Materialbahnoberfläche 20a infolge dieser Kraft erstmals mit Auftragsmedium 16 bedeckt werden. Darüber hinaus verbessert die vorstehend angesprochene Kraft auch die Bindung, die das Auftragsmedium 16 mit der Oberfläche 20a der Materialbahn 20 eingeht.Finally, electrical forces can also contribute to improving the leveling and fixing of the application layer 24 on the material web 20. For this purpose, for example, a further electrode arrangement in the form of a plate electrode 46 can be provided, which is kept at a predetermined electrical potential V 4 . A relatively homogeneous electric field is formed between this plate electrode 46 and the support roller 22 held at ground potential, which exerts a force directed toward the substrate U on the application medium. At places on the material web surface 20a to which too much application medium 16 has been applied, this force causes the excess application medium to be displaced and thus to even out the application layer 24. In extreme cases, areas of the material web surface 20a which have not been covered up to now can occur as a result of this Force be covered with application medium 16 for the first time. In addition, the force mentioned above also improves the bond that the application medium 16 enters into with the surface 20a of the material web 20.

Anzumerken ist noch, dass auch die Aufladung, die das Auftragsmedium 16 im Bereich des Vorhangs 18 durch die Entladungen E erfährt, im Zusammenwirken mit der auf Massepotential gehaltenen Stützwalze 22 zu einer derartigen, auf den Untergrund U zu gerichteten Kraft führt. Dies ist in der vergrößerten Darstellung des Details D durch die Pfeile F angedeutet. It should also be noted that the charging, which is the application medium 16 in the area of the curtain 18 through the discharges E, in Cooperation with the support roller 22 held at ground potential of such a force directed at the underground U leads. This is in the enlarged representation of the detail D indicated by the arrows F.

Die Stützwalze 22 kann auf unterschiedliche Art und Weise auf dem Massepotential VE gehalten werden. Beispielsweise kann die Walzeachse A mit einem Schleifkontakt in Verbindung stehen, wie er beispielsweise in der DE 197 33 333 A1 beschrieben ist. Zusätzlich oder alternativ kann jedoch auch ein mit der Oberfläche 22a der Walze 22 in Verbindung stehender Schleifkontakt 50 vorgesehen sein. Schließlich kann auch die Materialbahn 20 über beispielsweise von Bahnleitelementen 48 gebildete Kontakte auf Massepotential VE gehalten werden.The support roller 22 can be kept at the ground potential V E in different ways. For example, the roller axis A can be connected to a sliding contact, as described, for example, in DE 197 33 333 A1. Additionally or alternatively, however, a sliding contact 50 connected to the surface 22a of the roller 22 can also be provided. Finally, the material web 20 can also be held at ground potential V E via contacts formed by web guiding elements 48, for example.

In Fig. 2 ist eine mit Blickrichtung in Laufrichtung L genommene Ansicht der Auftragsvorrichtung 10 dargestellt. Anhand dieser Darstellung soll eine Möglichkeit erläutert werden, wie der Auftragmedium-Vorhang 18 auch im Bereich seiner Seitenränder 18a stabilisiert werden kann. Die den Vorhang 18 zusammenzuziehen suchende Oberflächenspannung des Auftragsmediums 16 wirkt sich nämlich hauptsächlich in den Randbereichen 18 des Vorhangs 18 aus. Sie führt dort zu einer seitlichen Kontraktion des Vorhangs 18 und dessen Verdickung. Um diesem Effekt entgegenzuwirken, sind bei der in Fig. 2 dargestellten Ausführungsform Führungsfeisten 54 vorgesehen, welche am Auftragswerk 12 derart angebracht sind, dass sie den aus der Abgabedüse 14 austretenden Vorhang 18 auffangen und auf seinem Fallweg bis unmittelbar vor die Oberfläche 20a der Materialbahn 20 führen.2 is a view taken with the viewing direction in the running direction L. the application device 10 shown. Based on this representation, a Possibility to explain how the application medium curtain 18 also in the Area of its side edges 18a can be stabilized. The the curtain 18 contracting surface tension of the application medium 16 acts mainly in the edge areas 18 of the Curtain 18 out. There it leads to a lateral contraction of the Curtain 18 and its thickening. To counteract this effect are guide strips 54 in the embodiment shown in FIG. 2 provided which are attached to the applicator 12 such that they catch and open the curtain 18 emerging from the dispensing nozzle 14 its fall path up to just in front of the surface 20a of the material web 20 to lead.

Die Wirkung der Randleisten 54 beruht auf den Adhäsionskräften zwischen dem Auftragsmedium 16 und der Oberfläche der Randleisten 54. Im Hinblick auf eine möglichst gute Adhäsion sollte der Randwinkel bzw. Benetzungswinkel α eines Tröpfchens T von Auftragsmedium 16 auf der Oberfläche 54a der Randleisten 54 einen möglichst niedrigen Wert aufweisen. Dies kann beispielsweise dadurch erreicht werden, dass man die Oberfläche der Randleisten 54 aus einem Material mit hoher Oberflächenspannung herstellt. Darüber hinaus kann die Benetzung zwischen Auftragsmedium 16 und Randleisten 54 durch eine aufgeraute, beispielsweise gezahnte Oberflächenstruktur der Randleisten 54 verbessert werden. Dies kann man beispielsweise dadurch erreichen, dass man Gewindestangen als Randleisten 54 einsetzt.The effect of the edge strips 54 is based on the adhesive forces between the application medium 16 and the surface of the edge strips 54. Im With a view to the best possible adhesion, the contact angle or Wetting angle α of a droplet T of application medium 16 on the Surface 54a of the edge strips 54 has the lowest possible value exhibit. This can be achieved, for example, by: the surface of the edge strips 54 made of a material with high Creates surface tension. In addition, wetting between application medium 16 and edge strips 54 by a roughened, for example, toothed surface structure of the edge strips 54 is improved become. This can be achieved, for example, by: Threaded rods used as edge strips 54.

Eine weitere Möglichkeit, um die Adhäsion des Auftragsmediums 16 an den Randleisten 54 verbessern zu können, besteht darin, dass man im Wesentlichen parallel zu den Randleisten 54 Elektrodenleisten 56 vorsieht, an welche man eine vorbestimmte elektrische Spannung V5 anlegt. Hierdurch wird, ähnlich wie dies vorstehend für die Anordnung gemäß Fig. 1 beschrieben worden ist, auf das Auftragsmedium eine attraktive Kraft ausgeübt.A further possibility in order to be able to improve the adhesion of the application medium 16 to the edge strips 54 is to provide electrode strips 56 essentially parallel to the edge strips 54, to which a predetermined electrical voltage V 5 is applied. As a result, an attractive force is exerted on the application medium in a manner similar to that described above for the arrangement according to FIG. 1.

Um die Randleisten 54 an die jeweils gewünschte Arbeitsbreite, d.h. die jeweils vorliegende Breite der Materialbahn 20 anpassen zu können, sind diese am Auftragswerk 12 in Querrichtung Q verschiebbar angeordnet, was in Fig. 2 durch die Pfeile q angedeutet ist. Darüber hinaus können die Randleisten 54 an dem Auftragswerk 12 auch schwenkbar angeordnet sein, und zwar um zur Längsrichtung L oder/und zur Querrichtung Q im Wesentlichen parallel verlaufende Achsen, wobei in Fig. 2 durch die Pfeile I lediglich eine Verschwenkbarkeit in Querrichtung Q, d.h. um eine zur Längsrichtung L im Wesentlichen parallel verlaufende Achse angedeutet ist.To the edge strips 54 to the desired working width, i.e. the to be able to adjust the respective present width of the material web 20 these are arranged displaceably in the transverse direction Q on the application unit 12, what is indicated in Fig. 2 by the arrows q. In addition, the Edge strips 54 are also pivotally arranged on the application unit 12 be, namely to the longitudinal direction L or / and the transverse direction Q in Essentially parallel axes, with the arrows in FIG. 2 I only a pivotability in the transverse direction Q, i.e. for one for Longitudinal direction L substantially parallel axis is indicated.

Claims (36)

  1. Device (10) for applying liquid or pasty application medium (16) to one or both sides of a moving substrate (U), comprising an applicator unit (12) which is arranged at a distance from the substrate (U) and discharges the application medium (16) onto the substrate (U) in the form of a free application medium jet (18),
    the substrate (U), in the case of direct application, being the surface (20a) of a material web (20), in particular of paper or board, and, in the case of indirect application, being the surface of a transfer element, preferably of a transfer roll, which then transfers the application medium to the surface of the material web,
    and in the region of the applicator unit (12) there being provided a device (30) for producing an electric field, which exerts on the application medium jet (18) moving from the applicator unit (12) to the substrate (U) a force which assists its movement, characterized in that, as the device for producing the electric field, the applicator unit (12) is connected to a first potential source in order to keep the applicator unit (12) at a first predetermined electric potential (V1), and in that the substrate (U) is connected to a second potential source in order to keep the substrate (U), at least in the vicinity of the applicator unit (12), at a second predetermined electric potential (VE or V2).
  2. Application device according to Claim 1, characterized in that the applicator unit is a curtain applicator unit (12) which discharges the application medium onto the substrate (U) as an application medium curtain (18) which moves from the applicator unit (12) to the substrate (U) substantially under the force of gravity.
  3. Application device according to Claim 1, characterized in that the applicator unit is a free jet nozzle applicator unit, which discharges the application medium onto the substrate as an application medium jet which moves from the applicator unit to the substrate substantially on account of the expulsion momentum imparted to it by the applicator unit.
  4. Application device according to one of the preceding claims, characterized in that an electrode arrangement (30) is provided on the upstream side of the applicator unit (12) and in its vicinity, preferably at a distance from the substrate (U), which is kept at a predetermined electric potential (V1).
  5. Device (10) for applying liquid or pasty application medium (16) to one or both sides of a moving substrate (U), comprising an applicator unit (12) which is arranged at a distance from the substrate (U) and discharges the application medium (16) onto the substrate (U) in the form of a free application medium jet (18),
    the substrate (U), in the case of direct application, being the surface (20a) of a material web (20), in particular of paper or board, and, in the case of indirect application, being the surface of a transfer element, preferably of a transfer roll, which then transfers the application medium to the surface of the material web,
    and in the region of the applicator unit (12) there being provided a device (30) for producing an electric field, which exerts on the application medium jet (18) moving from the applicator unit (12) to the substrate (U) a force which assists its movement, characterized in that, as the device for producing the electric field, an electrode arrangement (30) is provided on the upstream side of the applicator unit (12) and in its vicinity, preferably at a distance from the substrate (U), which is kept at a predetermined electric electrode arrangement potential (V3).
  6. Application device according to Claim 4 or 5, characterized in that the electrode arrangement comprises at least one flat electrode, the flat electrode preferably having a plurality of projections or needle points on its side pointing toward the substrate.
  7. Application device according to Claim 4 or 5, characterized in that the electrode arrangement (30) comprises a plurality of individual electrodes, preferably needle electrodes (32), arranged adjacent to one another in the transverse direction of the substrate (U).
  8. Application device according to one of the preceding claims, characterized in that downstream of the position (P) at which the application medium (16) strikes the substrate there is provided a further device (46) for producing an electric field, which exerts on the application medium (16) applied to the substrate (U) a force which is directed toward the substrate (U).
  9. Application device according to Claim 8, characterized in that the further field production device has a further electrode arrangement (46) which is adjacent to the substrate (U) and which is preferably kept at a further predetermined electric potential (V4).
  10. Application device according to one of the preceding claims, characterized in that the first predetermined, and/or the electrode arrangement potential and/or the further predetermined electric potential (V1, V3, V4) have a value of between about 5 kV and about 60 kV, preferably about 30 kV.
  11. Application device according to one of the preceding claims, characterized in that the second predetermined electric potential (V2) is the earth potential (VE).
  12. Application device according to Claim 12, characterized in that a backing element, preferably a backing roll (22) which, in the case of direct application, supports the material web (20) in the region of the applicator unit (12) or, in the case of indirect application, on the surface of which the applicator unit applies the application medium, is in contact with an electrode in order to keep said roll at the second predetermined electric potential (V2).
  13. Application device according to Claim 12, characterized in that the surface (22a) of the backing element (22) is in wiping contact with the electrode (50).
  14. Application device according to Claim 12 or 13, characterized in that the electrode is in contact with a bearing shaft (A) of the backing roll (22).
  15. Application device according to one of Claims 11 to 14, characterized in that, in the case of direct application, the material web (20) is kept at the second predetermined electric potential (V2) by an electrode (48) formed, for example, as a web guide element.
  16. Application device according to one of the preceding claims, characterized in that, in addition to or instead of the electrode arrangement (30) and/or the further electrode arrangement (46), a magnetic field device is provided for influencing the movement of the application medium (16).
  17. Application device according to one of the preceding claims, characterized in that, in the direction of movement (L) of the substrate (U), a device (34) for attenuating the air boundary layer (G) carried along by the substrate (U) is arranged upstream of the electrode arrangement (30).
  18. Application device according to Claim 17, characterized in that the air boundary layer attenuation device comprises a suction device (34).
  19. Application device according to Claim 18, characterized in that a trailing scraper (36) in wiping contact with the substrate (U) is provided at the downstream end of the suction device (34).
  20. Application device according to one of Claims 17 to 19, characterized in that a further electrode arrangement (40) is provided in the region of the air boundary layer attenuation device (34), preferably between the downstream end of the suction device (34) and the trailing scraper (36).
  21. Application device according to Claim 20, characterized in that the further electrode arrangement (40) comprises a plurality of individual electrodes, preferably needle electrodes, arranged adjacent to one another in the transverse direction of the substrate.
  22. Application device according to Claim 20, characterized in that the further electrode arrangement (40) comprises at least one flat electrode which has a plurality of projections or needle points on its side pointing toward the substrate.
  23. Application device according to one of Claims 20 to 22, characterized in that the further electrode arrangement (40) has a distance from the substrate of between about 2 mm and about 30 mm.
  24. Application device according to one of Claims 20 to 23, characterized in that the electric potential of the further electrode arrangement (40) is kept floating.
  25. Application device according to one of Claims 20 to 24, characterized in that the further electrode arrangement (40) is arranged on the air boundary layer attenuation device (34) electrically insulated (42) from the latter.
  26. Application device according to one of the preceding claims, characterized in that the applicator unit (12) and/or the air boundary layer attenuation device (34) is kept at a predetermined electric potential (VE), preferably ground potential.
  27. Device (10) for applying liquid or pasty application medium (16) to one or both sides of a moving substrate (U), comprising a curtain applicator unit (12) which discharges the application medium (16) onto the substrate (U) as a curtain (18) or veil moving substantially under the force of gravity, the substrate (U), in the case of direct application, being the surface (20a) of a material web (20), in particular of paper or board, and, in the case of indirect application, being the surface of a transfer element, preferably of a transfer roll, which then transfers the application medium to the surface of the material web, edge guiding elements (54) being provided, which guide the lateral edges (18a) of the application medium curtain (18) at least on part of its movement under the force of gravity between the curtain applicator unit (12) and the substrate (U), characterized in that at least one edge guiding element (54) has a roughened or toothed surface (54a).
  28. Application device according to Claim 27, characterized in that the surface characteristics of at least one edge guiding element (54) are selected in such a way that the wetting angle (α), which depends on the characteristics of the application medium (16) and the surface (54a) of the edge guiding elements (54), is less than 90°.
  29. Application device according to Claim 27 or 28, characterized in that at least one edge guiding element (54) has an external thread.
  30. Application device according to one of Claims 27 to 29, characterized in that at least one edge guiding element (54) is fabricated from glass or metal.
  31. Application device according to one of Claims 27 to 30, characterized in that at least one edge guiding element (54) is arranged such that it can be displaced in the transverse direction (Q) of the substrate (U).
  32. Application device according to one of Claims 27 to 31, characterized in that the angle which an edge guiding element (54) forms with the vertical is adjustable.
  33. Application device according to one of Claims 27 to 32, characterized in that an electrode (56) is provided in the vicinity of at least one of the edge guiding elements (54), preferably extending substantially parallel to the latter, and is kept at a predetermined electric potential (V5).
  34. Method for applying liquid or pasty application medium (16) to one or both sides of a moving substrate (U), using an applicator unit (12) which is arranged at a distance from the substrate (U) and discharges the application medium (16) onto the substrate (U) in the form of a free application medium jet (18),
    the substrate (U), in the case of direct application, being the surface (20a) of a material web (20), in particular of paper or board, and, in the case of indirect application, being the surface of a transfer element, preferably of a transfer roll, which then transfers the application medium to the surface of the material web,
    and in the region of the applicator unit (12) there being provided a device (30) for producing an electric field, which exerts on the application medium jet (18) moving from the applicator unit (12) to the substrate (U) a force which assists its movement, characterized in that, in order to produce the electric field, the applicator unit (12) is kept at a first predetermined electric potential (V1), and in that the substrate (U), at least in the vicinity of the applicator unit (12), is kept at a second predetermined electric potential (VE or V2).
  35. Method according to Claim 34, characterized in that the first predetermined electric potential (V1) has a value of between 5 kV and 60 kV, preferably approximately 30 kV.
  36. Method according to Claim 34 or 35, characterized in that the second predetermined electric potential (V2) is the earth potential (VE).
EP01913875A 2000-03-14 2001-03-13 Application device and process Expired - Lifetime EP1266093B2 (en)

Applications Claiming Priority (5)

Application Number Priority Date Filing Date Title
DE10012256 2000-03-14
DE2000112256 DE10012256A1 (en) 2000-03-14 2000-03-14 Curtain coating applicator for a moving paper/cardboard web has electrodes at given electrical potentials to generate magnetic fields to affect the coating medium flow between the applicator and web surface in direct or indirect coating
DE10012347 2000-03-14
DE2000112347 DE10012347A1 (en) 2000-03-14 2000-03-14 Curtain coating applicator for a moving paper/cardboard web has electrodes at given electrical potentials to generate magnetic fields to affect the coating medium flow between the applicator and web surface in direct or indirect coating
PCT/EP2001/002828 WO2001068982A1 (en) 2000-03-14 2001-03-13 Application device

Publications (3)

Publication Number Publication Date
EP1266093A1 EP1266093A1 (en) 2002-12-18
EP1266093B1 true EP1266093B1 (en) 2004-05-19
EP1266093B2 EP1266093B2 (en) 2007-02-07

Family

ID=26004823

Family Applications (1)

Application Number Title Priority Date Filing Date
EP01913875A Expired - Lifetime EP1266093B2 (en) 2000-03-14 2001-03-13 Application device and process

Country Status (6)

Country Link
EP (1) EP1266093B2 (en)
JP (1) JP2003527237A (en)
AT (1) ATE267293T1 (en)
CA (1) CA2403004A1 (en)
DE (1) DE50102327D1 (en)
WO (1) WO2001068982A1 (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050098285A1 (en) 2002-06-24 2005-05-12 Richard Aust Machine for making/treating a sheet of material
DE10236908A1 (en) * 2002-08-12 2004-02-26 Voith Paper Patent Gmbh Device for applying an application medium to a moving surface
DE10245075A1 (en) * 2002-09-27 2004-04-01 Voith Paper Patent Gmbh commissioned
DE10359677A1 (en) * 2003-12-18 2005-07-14 Voith Paper Patent Gmbh Method for one-sided or double-sided curtain or veiling application to the surface of a moving material web, in particular of paper or cardboard
FI116738B (en) * 2004-07-20 2006-02-15 Metso Paper Inc Curtain Coating Unit and Curtain Coating Method

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1989005477A1 (en) * 1987-12-03 1989-06-15 Eastman Kodak Company High speed curtain coating process and apparatus
US5290600A (en) * 1990-11-12 1994-03-01 Imperial Chemical Industries Plc Apparatus and process for producing sheets of material
US5295039A (en) * 1989-03-10 1994-03-15 Fuji Photo Film Co., Ltd. Method of applying single polar electro-static charges to continuously travelling long web support, and apparatus practicing same
US5609923A (en) * 1995-02-25 1997-03-11 Eastman Kodak Company Method of curtain coating a moving support wherein the maximum practical coating speed is increased

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3369522A (en) * 1965-01-18 1968-02-20 Continental Oil Co Curtain coating apparatus
EP0440279A1 (en) * 1990-01-29 1991-08-07 Agfa-Gevaert N.V. Curtain coater for photographic elements
DE19631888A1 (en) * 1996-08-07 1998-02-12 Voith Sulzer Papiermasch Gmbh Applicator for direct or indirect application of a liquid or pasty coating medium to a running material web, in particular made of paper or cardboard
DE19735588A1 (en) * 1997-04-21 1999-02-18 Jagenberg Papiertech Gmbh Coating a moving web
DE19716466A1 (en) * 1997-04-21 1998-10-22 Bachofen & Meier Ag Method and device for applying dispersions to a material web
DE19755625A1 (en) * 1997-12-15 1999-07-01 Jagenberg Papiertech Gmbh Slot nozzle for coating material webs, in particular paper or cardboard webs with pigment coating ink
DE19803240A1 (en) * 1998-01-28 1999-07-29 Voith Sulzer Papiertech Patent Paint curtain applicator
DE19903559B4 (en) * 1998-01-30 2004-02-26 Mitsubishi Paper Mills Limited Process and apparatus for curtain coating
DE19807000A1 (en) * 1998-02-19 1999-08-26 Voith Sulzer Papiertech Patent Device and method for applying a liquid or pasty application medium to an application area of a running substrate

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1989005477A1 (en) * 1987-12-03 1989-06-15 Eastman Kodak Company High speed curtain coating process and apparatus
US5295039A (en) * 1989-03-10 1994-03-15 Fuji Photo Film Co., Ltd. Method of applying single polar electro-static charges to continuously travelling long web support, and apparatus practicing same
US5290600A (en) * 1990-11-12 1994-03-01 Imperial Chemical Industries Plc Apparatus and process for producing sheets of material
US5609923A (en) * 1995-02-25 1997-03-11 Eastman Kodak Company Method of curtain coating a moving support wherein the maximum practical coating speed is increased

Also Published As

Publication number Publication date
JP2003527237A (en) 2003-09-16
WO2001068982A1 (en) 2001-09-20
EP1266093A1 (en) 2002-12-18
EP1266093B2 (en) 2007-02-07
DE50102327D1 (en) 2004-06-24
ATE267293T1 (en) 2004-06-15
CA2403004A1 (en) 2001-09-20

Similar Documents

Publication Publication Date Title
EP1367174B1 (en) Application device
EP0881330B1 (en) Process and apparatus for applying a fluid or pasty material onto a moving web
DE10012256A1 (en) Curtain coating applicator for a moving paper/cardboard web has electrodes at given electrical potentials to generate magnetic fields to affect the coating medium flow between the applicator and web surface in direct or indirect coating
EP1516087B2 (en) Device for coating and drying the front and back of a web, particularly one consisting of paper or cardboard
DE10012344A1 (en) Continuous liquid curtain coating, for paper or card operates under specified conditions of temperature, pressure and viscosity, leaving thin wet film on surface
DD203500A5 (en) DEVICE FOR APPLYING POWDER PARTS
EP1266093B1 (en) Application device and process
DE10232949A1 (en) Web coating curtain applicator, for wide paper/cardboard webs moving at high speeds, has side guides with jet openings to stabilize the falling curtain coating to give a consistent edge coating application
DE10012347A1 (en) Curtain coating applicator for a moving paper/cardboard web has electrodes at given electrical potentials to generate magnetic fields to affect the coating medium flow between the applicator and web surface in direct or indirect coating
DE60123230T2 (en) ELECTRO-ATTRACTED COATING METHOD AND DEVICE WITH FOCUSED MATERIAL RAIL LOADING FIELD
DE2310526C2 (en) Device for applying a line of different coating compounds to both sides of a moving paper web
DE10057734A1 (en) Web curtain coating station, especially using a pigment suspension, has a guide in the free fall path of the coating to divide the path into two sections and reduce distorting effects on the laid coating at the moving substrate surface
DE10012345A1 (en) Web coating station, for paper or cardboard, comprises applicator with delivery jet, to form structured free-fall coating curtain to moving web surface, with adjustments to set relative alignments of applicator and web
DE3122605C2 (en)
DE10057731A1 (en) Assembly discharges liquid coating to fast moving web paper descending over a roller at a defined angle
DE102005035317A1 (en) Method for directly applying layers of a liquid-to-pasty medium to a paper, cardboard or other fibrous strip comprises releasing the media separately from one another from chambers and combining to form a curtain
EP1375746B1 (en) Process and apparatus for applying onto one side or both sides a fluid to pasty medium
DE10057732A1 (en) Web curtain coating station has a rotating roller in the curtain fall path, to divide the coating path into two sections to set the coating speed according to the substrate speed to prevent coating distortions
DE1950430A1 (en) Liquid jet recorder
DE102010041713A1 (en) Device for direct or indirect application of liquid to pasty application medium and method for operating such a device
EP1209274B1 (en) Curtain coater
DE102006036450A1 (en) applicator
DE102006036448A1 (en) applicator
US20040216663A1 (en) Medium application device
DE10125376A1 (en) Paper or carton curtain-coating assembly has combined suction/blower unit disrupting air boundary layer over moving web

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

17P Request for examination filed

Effective date: 20020909

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

17Q First examination report despatched

Effective date: 20030502

RTI1 Title (correction)

Free format text: APPLICATION DEVICE AND PROCESS

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT DE FI SE

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

Free format text: GERMAN

REF Corresponds to:

Ref document number: 50102327

Country of ref document: DE

Date of ref document: 20040624

Kind code of ref document: P

REG Reference to a national code

Ref country code: SE

Ref legal event code: TRGR

REG Reference to a national code

Ref country code: IE

Ref legal event code: FD4D

PLAQ Examination of admissibility of opposition: information related to despatch of communication + time limit deleted

Free format text: ORIGINAL CODE: EPIDOSDOPE2

PLBQ Unpublished change to opponent data

Free format text: ORIGINAL CODE: EPIDOS OPPO

PLBI Opposition filed

Free format text: ORIGINAL CODE: 0009260

PLAQ Examination of admissibility of opposition: information related to despatch of communication + time limit deleted

Free format text: ORIGINAL CODE: EPIDOSDOPE2

PLAR Examination of admissibility of opposition: information related to receipt of reply deleted

Free format text: ORIGINAL CODE: EPIDOSDOPE4

PLBQ Unpublished change to opponent data

Free format text: ORIGINAL CODE: EPIDOS OPPO

PLAB Opposition data, opponent's data or that of the opponent's representative modified

Free format text: ORIGINAL CODE: 0009299OPPO

PLAQ Examination of admissibility of opposition: information related to despatch of communication + time limit deleted

Free format text: ORIGINAL CODE: EPIDOSDOPE2

PLAR Examination of admissibility of opposition: information related to receipt of reply deleted

Free format text: ORIGINAL CODE: EPIDOSDOPE4

PLBQ Unpublished change to opponent data

Free format text: ORIGINAL CODE: EPIDOS OPPO

PLAB Opposition data, opponent's data or that of the opponent's representative modified

Free format text: ORIGINAL CODE: 0009299OPPO

PLAX Notice of opposition and request to file observation + time limit sent

Free format text: ORIGINAL CODE: EPIDOSNOBS2

26 Opposition filed

Opponent name: BACHOFEN+MEIER AG

Effective date: 20050221

R26 Opposition filed (corrected)

Opponent name: BACHOFEN+MEIER AG

Effective date: 20050221

R26 Opposition filed (corrected)

Opponent name: BACHOFEN+MEIER AG

Effective date: 20050221

PLBB Reply of patent proprietor to notice(s) of opposition received

Free format text: ORIGINAL CODE: EPIDOSNOBS3

RAP2 Party data changed (patent owner data changed or rights of a patent transferred)

Owner name: VOITH PATENT GMBH

PUAH Patent maintained in amended form

Free format text: ORIGINAL CODE: 0009272

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

Free format text: STATUS: PATENT MAINTAINED AS AMENDED

27A Patent maintained in amended form

Effective date: 20070207

AK Designated contracting states

Kind code of ref document: B2

Designated state(s): AT DE FI SE

REG Reference to a national code

Ref country code: SE

Ref legal event code: RPEO

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

Ref country code: FI

Payment date: 20080314

Year of fee payment: 8

Ref country code: SE

Payment date: 20080313

Year of fee payment: 8

PLAB Opposition data, opponent's data or that of the opponent's representative modified

Free format text: ORIGINAL CODE: 0009299OPPO

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

Ref country code: AT

Payment date: 20080314

Year of fee payment: 8

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

Ref country code: DE

Payment date: 20080321

Year of fee payment: 8

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

Ref country code: FI

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

Effective date: 20090313

Ref country code: AT

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

Effective date: 20090313

EUG Se: european patent has lapsed
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: 20091001

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

Ref country code: SE

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

Effective date: 20090314