EP2157240B1 - Curtain application device - Google Patents

Description

The invention relates to a machine for applying a liquid or pasty application medium on at least one surface of a moving material web, in particular made of paper or cardboard by means of at least one curtain applicator and drying the applied application medium by means of at least one non-contact drying device; wherein the material web in the machine passes a plurality of deflecting arrangements which touch the material web, which define mutually offset or / and in different directions extending sections of the material web course; wherein the curtain coater the application medium from at least one discharge opening, in particular a slot or Gleitschichtdüse, in the form of a one- or multi-layer curtain, which releases under the influence of gravity and possibly influence further forces towards the associated surface of the web in an application section of the material web course which is substantially horizontal or corresponding to a radius of a deflection and support roller of the curtain applicator or at least has a horizontally greater movement speed component than in the vertical direction; wherein the material web in at least one of the application section subsequent drying section of the material flow passes through the or at least one non-contact, the application medium of a heat-applying drying device to at least partially dry the applied application medium; and wherein the material web in the course and / or at the end of the order section by a - if present - the deflection and support roller possibly comprehensive first deflection such in at least one deflection is deflected such that the material web after the deflection at least in a direct to this deflection the following first section of the material web course, at least initially substantially vertically downwards or a larger moving velocity component in the vertical direction down than before the diversion has.

Such so-called curtain coating machines, also known by the term "curtain coater", are known in various designs and have gained in importance in recent years for the coating of paper and cardboard. An example is in DE 10 2005 027 831 A1 on which the preamble of claim 1 is based.

When painting paper and cardboard, the drying of the coating layer is initially contactless, so that the still moist surface is not damaged. This applies regardless of the order procedure. In contrast, a so-called cast coating method is based on contact drying with a heated cast cylinder, as in US Pat DE 10 2006 010 348 A1 disclosed.

In contactless drying, the water is usually heated by infrared radiators or by hot air dryer and evaporated in the contactless drying section. It is well known that drying should begin as soon as possible after painting. This prevents penetration of soluble constituents from the liquid coating color into the paper, i. H. whose fiber network, migrate, or the extent of this migration is limited. The liquid components of the ink should be preserved in the filler matrix of the coating color, generally the application medium, since they provide good quality for later printing.

It has therefore attempted to build the coating systems used for painting so that the drying begins after the shortest possible distance to the coating unit. Fig. 8 shows several examples of common coating methods, namely for the pawl or knife coating (subfigures 8a) and 8b)) and the film coating ( Fig. 8c )). In such contacting brushing method, the first drying element is usually arranged after only one web deflection. The distance between paint application and Start of drying is usually between 2 and 8 meters.

In recent years, a new application process has gained in importance with the "Curtain Coater", ie curtain painting. There are several production plants as well as pilot plants. When using a falling curtain or veil, however, due to gravity, a certain arrangement of the coating color, generally the application medium dispensing nozzle to the web (in particular paper or board web) is given. The material web must be substantially horizontal at the moment of the order. Subsequently, the coated side can not be touched, which results in restrictions for the subsequent arrangement of a drying line. Typical arrangements of the prior art are in Fig. 7 shown. The lane must change direction several times before getting into a dry section above. The distance from the place of the job to the beginning of the drying is thus significantly longer than other coating methods, which is disadvantageous and can have particular disadvantages for the print quality and greater mechanical complexity due to the use of relatively many guide or guide rollers (Leit- or Deflection rollers) means.

It is accordingly an object of the invention to arrange a drying line following a curtain coater so relative to the curtain applicator, that a comparatively short distance between the place of the order (the order line) and the beginning of the drying (the drying line) is realized.

To solve this problem, the machine is proposed with the features of claim 1. According to the invention, the first section of the material web progression immediately following the deflection in the course or / and at the end of the application section is a drying section in which the material web passes at least one non-contact drying device subjecting the application medium to a heat effect. It has surprisingly been found that the first section of the material web course immediately following the first deflection arrangement is well suited for the arrangement of at least one drying element, that this section of the material web course designated as the "first section" can thus serve as a drying section or drying section.

In the present case, with regard to the term "section of the material web course", that is to say "job section", "first section" and with regard to possible further developments to be addressed below, "second section" and "third section" of the material web course are primarily intended for this section on the input side and on the output side is limited in each case by a deflecting arrangement which contacts the material web. If a deflection and support roller is used in association with an application head of a curtain applicator, this deflection and support roller (supporting and deflection roller) can also define the application section alone and give it a curved course.

A non-contact deflection arrangement does not limit a section of the material web course in this definition, which is to be considered primarily, and can accordingly be arranged, for example, in the middle of such a "section of the material web course".

If these definitions are taken as a basis, a contactless deflection arrangement can subdivide such a portion of the material web course bounding on the input side and output side into "subsections" of the material web course, namely into a subsection between the input-side contacting deflection arrangement and the contactless deflection arrangement and a subsection between the material non-contact deflection arrangement and the output side contacting deflection arrangement. But it can also be that an essential portion of such a portion of the web course runs along or through a non-contact deflection arrangement, so that this portion of the majority of the entire section.

It is mainly thought that the material web after the deflection in the course and / or at the end of the order section of / a the application medium of a heat-applying undergoing drying device of / a drying section is supplied such that the heat of the drying device on the application medium on a opposite begins at the lower level of the order.

Above all, it is also thought that the material web in the drying section or after the deflection by the first deflection arrangement, and - in the case of a further deflection of the material web following in the running direction of the material web prior to this further deflection - substantially vertically downwards running or a larger moving velocity component in the vertical direction down than before the deflection having the or at least one non-contact, the application medium undergoing heat application drying device happens.

Such a configuration of the machine is particularly preferred such that the material web, in the first section of the material web course immediately following the first deflecting arrangement, extends at least initially substantially vertically downwards or has a movement speed component which is larger in the vertical direction than in the horizontal direction.

It is preferred that the material web in the drying section or after the deflection by the first deflection arrangement, and - in the case of a further deflection in the direction of the material web further deflection of the web prior to this further deflection - substantially vertically downwardly extending or vertically downwards greater moving velocity component than in the horizontal direction having the or at least one non-contact, the application medium of a heat undergoing drying device happens.

Thus, that section or partial section of the material web course after the deflection arrangement is preferably used at the end of the application section as a drying section, in which the material web moves downwards and still does not undergo a renewed deflection.

According to the invention, it is also provided that the web of material in the drying section or in the first section of the material web course immediately following the first deflecting arrangement and / or in a second section of the material web course adjoining this after a second deflecting arrangement passes a non-contact deflection arrangement which forms the material web deflects by at least one deflection angle such that the material web at least in a material web exit region of the non-contact deflection arrangement extends substantially vertically upward or has a larger moving velocity component in the vertical direction upward than before the deflection by the non-contact deflection arrangement or a larger moving velocity component in the vertical direction upward than in Horizontal direction has. The first section of the material web course can thus extend along and beyond the contactless deflection arrangement. Alternatively or additionally, it is possible that the or a further non-contact deflection arrangement is arranged in a second section of the material web course following the first section of the material web course. For this purpose, it is primarily thought that the second deflection arrangement is arranged adjacent to an input of the contactless deflection arrangement and deflects the material web in such a way that the material web after the deflection by the second deflection arrangement initially runs essentially vertically downwards or initially after a larger movement velocity component in the vertical direction below as before the deflection by the second Deflection arrangement has or initially has a vertically larger downward movement velocity component than in the horizontal direction.

Regarding the non-contact deflection arrangement is proposed as particularly preferred that this is designed as a non-contact, the application medium of a heat-applying drying device or at least one non-contact, the application medium subjected to a heat drying device so that the applied application medium during deflection of a drying action is unterziehbar. A defined by the Umlenkanordnung "deflection" can thus serve as a drying section. It may be the first drying section after the curtain application or another, for example, second drying section after the curtain application.

It is particularly preferred that the drying section provided by the deflecting arrangement or its at least one drying device make up a major part of the first section of the material web course, which is preferably deflected by more than 90 °, most preferably by approximately 180 °, by the contactless deflecting arrangement and then expediently one can pass another deflection.

Further, it is proposed that the material web after the deflection by the non-contact deflection substantially vertically upward or at least a larger moving velocity component in the vertical direction upward than before the deflection by the non-contact deflection or at least one vertically upward movement speed component than in the horizontal direction having the or at least one non-contact, the application medium of a heat undergoing drying device happens.

Another possibility is that the material web after the deflection by the non-contact deflection arrangement and passing a third deflection in a subsequent third section of the web course passes at least one non-contact, the application medium undergoing heat application drying device. In this regard, it may be expediently provided that the third deflection arrangement is arranged adjacent to an output of the contactless deflection arrangement and deflects the material web in such a way that the material web after the deflection by the third deflection arrangement extends substantially vertically upward or a larger movement velocity component in the vertical direction upwards than before the deflection by the third deflection arrangement or has a vertically higher upward movement speed component than in the horizontal direction.

The drying section realized after the non-contact deflecting arrangement or the third deflecting arrangement by arranging the drying device may be the first or a further, for example second or third, drying section after the curtain application.

It may be expedient to provide that sections or sections of the material web course before and after the non-contact deflection arrangement provide for guiding the material web substantially parallel to one another.

A deflection realized by a respective contacting or non-contact deflection arrangement can take place in one or more stages, that is to say in a deflection angle or in several deflection angles resulting in an overall deflection angle. It is therefore also possible, in particular, for the first deflecting arrangement to comprise a first deflecting roller or a plurality of first deflecting rollers, by means of which the material web surrounds one first deflection angle or by a plurality of deflection angles to achieve a first total deflection angle is deflected, and / or that the second deflection arrangement comprises a deflection roller or a plurality of deflection rollers, by means of which the material web to a second deflection angle or to a plurality of deflection to achieve a second total Deflection angle is deflected, and / or that the third deflection arrangement comprises a third deflection roller or a plurality of third deflection rollers, by means of which the material web is deflected by a third deflection angle or by a plurality of deflection to achieve a third total deflection angle.

The machine may also contain several curtain coating units that passes the web. For this purpose, it is concretely proposed that in the course of the material web the at least one curtain application unit passes at least one further curtain applicator, which comprises the application medium from at least one delivery opening, in particular from a slot nozzle or sliding layer nozzle, in the form of a monolayer or multilayer curtain under the influence of gravity and, if appropriate, influence of further forces towards the assigned, same or - preferably - other surface of the material web in a further application section of the material web course. The further application section extends which curves essentially horizontally or according to a radius of a deflection and support roller of the curtain applicator or has at least one movement speed component greater in the horizontal direction than in the vertical direction, wherein the material web has at least one further drying section of the material course in at least one further drying section following the further application section non-contact, the application medium of a heat undergoing drying device happens to at least partially dry the applied application medium; and wherein the material web in the course and / or at the end of the further order section is deflected by at least one deflection angle by a further first deflection arrangement, that the material web after the deflection at least in a direct to this deflection the following further first section of the material web course at least initially substantially vertically downwards or has a larger moving velocity component in the vertical direction down than before the deflection. It can therefore be provided on the same material web surface or a separate order on both surfaces (front and back) of the material web, a multi-stage medium order.

The application media used in multi-layer application may be the same, but preferably different, z. B. thickness, coating color, etc ..

Also concerning the at least one further curtain applicator, the invention can be realized with its training proposals. It is therefore proposed according to the invention that the further first section of the material web course directly following the deflection during the course and / or at the end of the further application section is a further drying section in which the material web or at least one contactless further drying device subjecting the application medium to a heat action happens. Alternatively or additionally, it is proposed that the material web after the deflection in the course and / or at the end of the further order section of a further drying device of the further drying section under the application medium is supplied such that the heat action of the further drying device on the application medium on a relative to the further order section of lower altitude begins.

Preferably, it is provided that the material web course after the deflection in the course and / or at the end of the other order section, in particular in the other first section and optionally in a subsequent second section and / or further third section of the material web course, the teaching of the invention and corresponds to the training suggestions given above.

It is generally thought that sections or subsections of the material web course after the application section and after the further application section provide movement speed components of the material web in mutually opposite horizontal directions. In this case, it may be expedient to provide that sections or subsections of the material web course after the application section and after the further application section provide a substantially parallel guidance of the material web with movement velocity components of the material web in mutually opposite horizontal directions.

In general, it is proposed to lay the beginning of the drying section as close as possible to the point of the application medium order (color order), for which the web is deflected downwards after the curtain application. Appropriately, then the beginning of the drying is lower than the point of impact of the application medium. In the course of single or multi-stage drying, the material web is then preferably deflected by at least about 90 ° and preferably by about 180 °.

• wenigstens ein Auftragswerk zum Auftragen von flüssigem Auftragsmedium,
• das Auftragswerk ist ein Vorhang-Auftragswerk (so genannter Curtain Coater),
• das Vorhang-Auftragswerk weist wenigstens eine Schlitzdüse (slot die) oder eine Gleitschichtdüse (slide die) für die Abgabe des Auftragsmediums auf,
• das Auftragswerk kann als Doppelanordnung (Double-Die), Twin-Die, Tandem-Die ausgebildet sein.
• mit dem Auftragswerk wird das Auftragsmedium mit mindestens einem Strich aufgetragen, z. B. auf die Oberseite der Materialbahn,
• die Materialbahn wird aus der Waagrechten nach unten umgelenkt,
• unmittelbar nach dieser Umlenkung beginnt die Trockenstrecke,
• der Beginn der Trockenstrecke liegt tiefer als der Punkt des Auftragsmedium-Auftrags,
• eine Distanz zwischen dem Auftragsmedium-Auftrag (Farb-Auftrag) und dem Beginn der Trocknung beträgt zwischen 2 Metern und 8 Metern entlang dem Materialbahnverlauf,
• die Trocknung erfolgt durch Infrarotstrahler und/oder durch Heißluftbeaufschlagung,
• die Trockenstrecke kann aus mehreren einzelnen Trocknern bestehen,
• die mit Auftragsmedium versehene (gestrichene) Materialbahnseite berührt kein berührendes Umlenkelement, insbesondere keine Umlenkwalze (Umlenkrolle), bevor die Trocknung abgeschlossen ist,
• die Trocknung kann mittels von der Materialbahn geradlinig durchlaufenen oder passierten und/oder mit von der Materialbahn mit einem Radius gekrümmt durchlaufenen oder passierten Trocknern erfolgen,
• die Materialbahn erfährt im Verlauf der ein- oder mehrstufigen Trocknung eine Richtungsänderung, die mindestens etwa 90° beträgt.

Features or elements of an embodiment of the invention may advantageously be the following:

• at least one applicator for applying liquid application medium,
• The commissioned work is a curtain coater (so-called curtain coater),
• the curtain applicator has at least one slot die or a slide die for dispensing the application medium,
• the commissioned work can be designed as a double arrangement (double-die), twin-die, tandem die.
• with the commissioned work, the order medium with at least applied a stroke, z. B. on the top of the web,
• the material web is deflected downwards from the horizontal,
• immediately after this diversion, the drying line begins
• the beginning of the drying section is lower than the point of the application medium order,
• a distance between the application medium order (color order) and the beginning of the drying is between 2 meters and 8 meters along the material web course,
• the drying takes place by infrared radiators and / or by hot air,
• the drying section can consist of several individual dryers,
• the coated material web side provided with the application medium does not touch any contacting deflecting element, in particular no deflecting roller (deflecting roller), before the drying has been completed,
• the drying can take place by means of dryers passed or passed in a straight line from the material web and / or with dryers passed through or passed through by a curved path of the material web,
• the material web experiences in the course of one or more stages drying a change in direction, which is at least about 90 °.

Not all of these features or elements must be realized in a solution according to the invention.

Fig. 1

zeigt ein erstes Beispiel für ein Vorhang-Auftragswerk (so genannter "Curtain Coater") zum Streichen einer Papier- oder Kartonbahn mit einem dem Auftragswerk unmittelbar nachfolgenden Trockner. Dieses Beispiel stellt kein Ausführungsbeispiel der in Anspruch 1 definierten Erfindung dar.

Fig. 2

zeigt ein erstes Ausführungsbeispiel für ein Vorhang-Auftragswerk (so genannter "Curtain Coater") zum Streichen einer Papier- oder Kartonbahn mit einem dem Auftragswerk unmittelbar nachfolgenden Trockner.

Fig. 3

zeigt ein zweites Ausführungsbeispiel für ein Vorhang-Auftragswerk (so genannter "Curtain Coater") zum Streichen einer Papier- oder Kartonbahn mit einem dem Auftragswerk nach einer berührungslosen Umlenkung unmittelbar nachfolgenden Trockner.

Fig. 4

zeigt ein drittes Ausführungsbeispiel für zwei entlang eines Verlaufs der Papier- oder Kartonbahn einander nachfolgende Vorhang-Auftragswerke für beidseitigen Strich, mit dem jeweiligen Vorhang-Auftragswerk jeweils unmittelbar nachfolgendem Trockner.

Fig. 5

zeigt ein viertes Ausführungsbeispiel für ein Vorhang-Auftragswerk (so genannter "Curtain Coater") zum Streichen einer Papier- oder Kartonbahn mit einem dem Auftragswerk unmittelbar nachfolgenden Trockner, wobei der als Heißlufttrockner ausgeführte Trockner einen gekrümmten Materialbahnverlauf vorsieht und damit eine Materialbahnumlenkungsfunktion erfüllt.

Fig. 6

zeigt ein fünftes Ausführungsbeispiel für ein Vorhang-Auftragswerk (so genannter "Curtain Coater") zum Streichen einer Papier- oder Kartonbahn mit einem dem Auftragswerk unmittelbar nachfolgenden Trockner ähnlich Fig. 5 mit allerdings beidseitiger Heißluftbeaufschlagung der Materialbahn.

Fig. 7

zeigt typische Beispiele herkömmlicher Anordnungen eines Vorhang-Auftragswerks mit nachfolgendem Trockner.

Fig. 8

zeigt typische Beispiele herkömmlicher Anordnungen eines berührenden Streichwerks mit nachfolgendem Trockner.

The invention will be explained in more detail below with reference to embodiments shown in the figures.

Fig. 1

shows a first example of a curtain coater (so-called "curtain coater") for painting a paper or board web with a dryer immediately following the applicator. This example does not set Embodiment of the invention defined in claim 1.

Fig. 2

shows a first embodiment of a curtain applicator (so-called "curtain coater") for painting a paper or board web with the applicator immediately following dryer.

Fig. 3

shows a second embodiment of a curtain applicator (so-called "curtain coater") for painting a paper or board web with the applicator after a non-contact deflection immediately following dryer.

Fig. 4

shows a third embodiment of two along a course of the paper or board web following each other curtain applicators for double-sided stroke, each with the respective curtain applicator immediately following dryer.

Fig. 5

shows a fourth embodiment of a curtain applicator (so-called "curtain coater") for painting a paper or board web with the applicator immediately following dryer, which runs as a hot air dryer dryer provides a curved material web course and thus fulfills a Materialbahnumlenkungsfunktion.

Fig. 6

shows a fifth embodiment of a curtain applicator (so-called "curtain coater") for painting a paper or board web with a dryer immediately following the commissioning similar Fig. 5 with however two-sided Heißluftbeaufschlagung the material web.

Fig. 7

shows typical examples of conventional arrangements of a curtain coater with subsequent dryer.

Fig. 8

shows typical examples of conventional arrangements of a contact brush with subsequent dryer.

Fig. 1 shows an example of a curtain coater 10 (also called a "curtain coater", also often abbreviated CC) having a curtain applicator head 12 to which is applied a liquid application medium, for example a coating color, which takes the form of a under the influence of gravity downwardly moving curtain or veil 14 is applied to a preferably at least approximately horizontally extending application portion 16 of the web 18. The material web is pulled with a pull group 32 by the coater, in particular coater.

In the example, the material web 18 is fed to the applicator unit via a plurality of deflection rollers, the deflection rollers 20 and 22 defining the application section 16. By the guide roller 22, the material web, in particular a paper or board web, deflected downward and then passes immediately into a first dryer 24. In the case of the example is a hot air dryer, the hot air at least against the application medium carrying material web surface, preferably against both web pages, blowing. The dryer can be designed so that tuyeres and suction zones alternate and a recirculation mode is realized in the water-laden air sucked between hot air nozzles (exhaust air AL or A) and blown after drying as supply air (supply air ZL or Z) again against the web.

After the example, after a further deflection of the web by two deflection rollers 26 and 28, the web is finished in a further hot air dryer 30, which can also operate on the recirculation principle. Until finished drying, the coated side of the web is not with Guided deflection rollers or pulleys. Via further deflection rollers and the pulling group 32, the material web is then fed to further processing or processing, for example a further coating unit, which applies to the same or the opposite material web side.

One or both dryers can also be designed as infrared radiation dryers.

In the first embodiment according to Fig. 2 In turn, the upper side of the material web, in particular the paper web, is coated with a curtain applicator 10, which has the curtain application head 12, which applies to the application section of the material web 18. The material web is deflected obliquely downwards by the deflection roller 22 and then passes immediately into a first dryer, in particular hot-air dryer 24. After passing through the dryer 24, the web is moved over the coated side by means of a non-contact deflection arrangement, for example a so-called Airturn ("AT"). ) 40, deflected by about 180 °. The Airturn 40 does not damage the surface of the web that is still wet by brushing, since the web is supported and deflected on an air cushion. After deflection, the web is then finished in a subsequent to the Airturn 40 further dryer, in particular hot air dryer 30, finished. Until the finished drying, the coated side of the web is not touched with deflecting rollers or deflection rollers. A train group 32 pulls the web through the machine. The material web 18 is shown after the train group 32 Fig. 2 a second curtain applicator with curtain application head 12 ', which in the order section 16' again on the same web page page as the curtain applicator 10 applied. In order to apply to the other material web side, could be provided between the train group 32 and the commissioned work 10 'a web turning device.

Fig. 3 shows one with Fig. 2 certain similarities have the second embodiment. The curtain applicator head 12 of the curtain applicator 10 also applies to the substantially horizontally extending application portion 16 of the web 18, and the web is then deflected by the guide roller 22 obliquely downwards. The dryer, in particular hot air dryer 24, however, a non-contact deflection arrangement, for example, an Airturn 40, downstream, which deflects the web over the coated side upwards, so that, for example, results in a nearly vertical material web course. After this deflection, the material web thus enters the first dryer, in particular hot-air dryer 24. After a touching deflection by a plurality of deflection rollers by about 180 °, the material web then passes in a nearly vertically downwardly extending portion of the second dryer, in particular hot air dryer 30, in which the Course is finished drying. The coated side of the web is not touched by rollers and other contacting diverters until the web is completely dry. After the finished drying by the dryer 30, a new deflection follows upwards, before the web reaches the pull group 32 pulling through the machine, after which the material web can then be fed to a second curtain applicator unit 10 '.

Both in the case of Fig. 2 as well as in the case of Fig. 3 For example, the arrangement of driers following the second applicator 10 'may correspond to the arrangement of driers following the respective first applicator 10.

Fig. 4 shows a third embodiment, which concretely shows a double-sided curtain order on the web 18. The curtain applicator 10 carries in the order section 16 on the top of the material web, in particular paper web on. By the guide roller 22, the web is deflected obliquely downward and passes through the dryer, in particular hot air dryer 24. Subsequently, the web over the still moist top by means of the Airturns 40 obliquely upwardly deflected, with the input side and output side of the Airturns 40 each one more down deflecting guide roller 50a or back to an oblique course deflecting guide roller 50b may be arranged.

After the deflection, the web is dried in an obliquely upwardly extending path section through the second dryer, in particular hot-air dryer 30. The train is maintained by the train group 32. By arranged before and after the train group pulleys, the web is deflected by more than 90 °, preferably 180 °, so that the web changes its direction and then in the order section 16 'the underside of the web by means of the curtain applicator head 12' of the curtain Order 10 'is deleted. This application section of the material web is defined by corresponding deflection rollers 20 'and 22'. The deflection roller 22 'deflects the material web obliquely downwards, and then follows an arrangement according to the first application work corresponding arrangement of a first dryer 24' and a second dryer 30 'and provided therebetween deflection devices, namely the Airturn 40' upstream pulley 50a and downstream pulley 50b. The drying of the bottom is thus carried out in a geometric arrangement analogous to the drying of the top.

Fig. 5 shows a fourth embodiment, in which the order section 16 subsequent, of the guide rollers 22 and 62 limited web portion 58 is a deflection section and at the same time a drying section in which the material web on the one hand by a non-contact deflector hot air dryer 60 by more than 90 °, im Trap of the embodiment by about 180 °, is deflected upward and on the other hand, during this deflection by the hot air which acts on the coated side of the web is dried. After the material web 18 has been deflected by the deflection roller 22, the web immediately reaches the area of influence of the deflection and drying device 60. It is a one-sided dryer which applies only hot air to the coated side of the web. The trajectory in or along the dryer is curved with a radium R.

In general, it is proposed that the web is deflected by at least 90 °, preferably by more than 90 °, and most preferably - as in the embodiment - by about 180 °. The dryer 60 may be configured to alternate along the curved contour blowing nozzles and suction zones, as in a detail of the overall illustration according to Fig. 5a ) subfigure 5b) indicated. Here, blowing nozzles 64 and intermediate suction zones are designated 66. The tuyeres blow hot air against the web. The water-laden air is sucked between the nozzles, so that the dryer can function according to the recirculation principle.

The embodiment of Fig. 6 differs from the embodiment of Fig. 5 essentially in that the material web 18 is dried from both sides. The hot-air drying device thus has, in addition to the dryer 60, a dryer arrangement acting on the other material web side, in the present case two successive dryers 70 and 72, which blow hot air against the uncoated side of the material web. The execution of the outer part of the drying device in several parts or individual dryers has the advantage that the assembly is facilitated. Advantageously, the dryers can be opened for cleaning. Each part of the dryer or each dryer preferably has a supply air and an exhaust air manifold and works according to the recirculation principle.

The embodiments according to FIGS. 5 and 6 appear particularly advantageous because on the one hand a very compact overall arrangement is achieved and on the other hand, the material web is dried immediately after painting.

Fig. 7 Figures 7a), 7b) and 7c) show typical prior art solutions for the arrangement of dryers following a curtain applicator. For corresponding parts are the same Reference numerals as used in the embodiments according to the invention. In the case of the known solution according to Fig. 7b ) is not applied to a running between two pulleys rectilinear material web section, but on a curved by a deflection and support roller material web section, which is also in a machine according to the invention into consideration.

Fig. 8 shows typical examples of known arrangements of a contacting coater with subsequent drying equipment. These are shown only for the sake of completeness, since due to completely different conditions little can be derived from such contacting coating machines for non-contact curtain coating machines. Fig. 8a) and Fig. 8b ) show known solutions for blade or knife coaters in which applied by an applicator 80 in excess and then then to adjust the correct dosage by a doctor device 82 excess application medium by means of, for example, a blade again removed. 84 denotes a gas infrared drier to which gas is supplied for operation. 86 each denotes a hot air dryer, wherein in the case of Fig. 8b ) is deflected over the coated side by means of an Airturns 88, to then finish drying in the hot air dryer 86.

Fig. 8c ) shows an example of a film coating arrangement 90, which applies the two-sided dosing onto the material web in contact with it. A first hot air dryer 86 follows after a deflection by an Airturn 88. A second hot air dryer 87 follows after another, this time touching diverter.

Claims (18)

1. Machine for applying a liquid or pasty application medium to at least one surface of a running material web (18), in particular of paper or cardboard, by means of at least one curtain applicator (10) and drying the applied application medium by means of at least one contactless drying device (24, 30; 60; 60, 70, 72);
   the material web (18) passing, in the machine, a plurality of deflecting arrangements (20, 22) which make contact with the material web and define sections of the material-web course which are offset with respect to one another and/or run in different directions;
   the curtain applicator (10) dispensing the application medium from at least one dispensing opening, in particular a slit nozzle or sliding coating nozzle, in the form of a single-layer or multiple-layer curtain under the influence of gravity and optionally the influence of further forces towards the associated surface of the material web in an application section (16) of the material-web course, which application section (16) runs substantially horizontally or in accordance with a radius of a deflecting and supporting roller of the curtain applicator or has at least one movement speed component which is greater in the horizontal direction than in the vertical direction; the material web passing, in at least one drying section of the material course which follows the application section, the or at least one contactless drying device (24, 30; 60; 60, 70, 72) which subjects the application medium to a thermal action, in order to dry the applied application medium at least partially; and,
   in the course and/or at the end of the application section, the material web being diverted by at least one deflecting angle by way of a deflecting arrangement (22) which possibly comprises the deflecting and supporting roller (if present), in such a way that, after the deflection, the material web at least initially runs substantially vertically downwards at least in a first section of the material-web course which follows the said deflection directly, or has a greater movement speed component in the vertical direction downwards than before the deflection;
   the first section of the material-web course which directly follows the deflection in the course and/or at the end of the application section (16) being a drying section, in which the material web passes the or at least one contactless drying device (24; 60; 60, 70, 72) which subjects the application medium to a thermal action,
   characterized in that the material web (18) passes a contactless deflecting arrangement (40; 60) in the drying section or in the first section of the material-web course which follows the deflecting arrangement (22) directly and/or in a second section of the material-web course which adjoins this after a second deflecting arrangement (50a), which contactless deflecting arrangement (40; 60) diverts the material web by at least one deflecting angle in such a way that, at least in a material-web outlet region of the contactless deflecting arrangement, the material web runs substantially vertically upwards or has a greater movement speed component in the vertical direction upwards than before the deflection by the contactless deflecting arrangement or has a greater movement speed component in the vertical direction upwards than in the horizontal direction.
2. Machine according to Claim 1, characterized in that the material web (18) is fed after the deflection in the course and/or at the end of the application section (16) to the/a drying device (24, 60; 60, 70, 72), which subjects the application medium to a thermal action, of the/a drying section, in such a way that the thermal action of the drying device on the application medium begins at a lower level with respect to the application section (16).
3. Machine according to Claim 1 or 2, characterized in that the material web (18) passes the or at least one contactless drying device (24) which subjects the application medium to a thermal action, in the drying section or after the deflection by the first deflecting arrangement (22) and, in the case of a further deflection, following in the running direction of the material web, of the material web before this further deflection, running substantially vertically downwards or having a greater movement speed component in the vertical direction downwards than before the deflection.
4. Machine according to one of Claims 1 to 3, characterized in that, in the first section of the material-web course which follows the first deflecting arrangement (22) directly, the material web (18) runs at least initially substantially vertically downwards or has a greater movement speed component in the vertical direction downwards than in the horizontal direction.
5. Machine according to one of Claims 1 to 4, characterized in that the material web (18) passes the or at least one contactless drying device (24) which subjects the application medium to a thermal action, in the drying section or after the deflection by the first deflecting arrangement (22) and, in the case of a further deflection, following in the running direction of the material web, of the material web before this further deflection, running substantially vertically downwards or having a greater movement speed component in the vertical direction downwards than in the horizontal direction.
6. Machine according to one of Claims 1 to 5, characterized in that the second deflecting arrangement (50a) is arranged adjacently to an inlet of the contactless deflecting arrangement (40) and deflects the material web in such a way that, after the deflection by the second deflecting arrangement (50a), the material web initially runs substantially vertically downwards or initially has a greater movement speed component in the vertical direction downwards than before the deflection by the second deflecting arrangement or initially has a greater movement speed component in the vertical direction downwards than in the horizontal direction.
7. Machine according to one of Claims 1 to 6, characterized in that the contactless deflecting arrangement (60) is configured as a contactless drying device which subjects the application medium to a thermal action or has at least one contactless drying device which subjects the application medium to a thermal action, with the result that the applied application medium can be subjected to a drying action during the deflection.
8. Machine according to one of Claims 1 to 7, characterized in that, after the deflection by the contactless deflecting arrangement (40), the material web (18) passes the or at least one contactless drying device (30) which subjects the application medium to a thermal action, running substantially vertically upwards or having at least one greater movement speed component in the vertical direction upwards than before the deflection by the contactless deflecting arrangement or having at least one greater movement speed component in the vertical direction upwards than in the horizontal direction.
9. Machine according to one of Claims 1 to 8, characterized in that, after the deflection by the contactless deflecting arrangement (40) and passing a third deflecting arrangement (50b) in a third section of the material-web course which adjoins the former, the material web (18) passes at least one contactless drying device (30) which subjects the application medium to a thermal action.
10. Machine according to Claim 9, characterized in that the third deflecting arrangement (50b) is arranged adjacently to an outlet of the contactless deflecting arrangement (40) and deflects the material web (18) in such a way that, after the deflection by the third deflecting arrangement (50b), the material web runs substantially vertically upwards or has a greater movement speed component in the vertical direction upwards than before the deflection by the third deflecting arrangement or has a greater movement speed component in the vertical direction upwards than in the horizontal direction.
11. Machine according to one of Claims 1 to 10, characterized in that sections or part sections of the material-web course before and after the contactless deflecting arrangement (40) provide substantially parallel guidance with respect to one another of the material web.
12. Machine according to one of Claims 1 to 11, characterized in that the first deflecting arrangement comprises a first deflecting roller or a plurality of first deflecting rollers, by means of which the material web is deflected by a first deflecting angle or by a plurality of deflecting angles in order to achieve a first overall deflecting angle, and/or in that the second deflecting arrangement comprises a deflecting roller or a plurality of deflecting rollers, by means of which the material web is deflected by a second deflecting angle or by a plurality of deflecting angles in order to achieve a second overall deflecting angle, and/or in that the third deflecting arrangement comprises a third deflecting roller or a plurality of third deflecting rollers, by means of which the material web is deflected by a third deflecting angle or by a plurality of deflecting angles in order to achieve a third overall deflecting angle.
13. Machine according to one of Claims 1 to 12, characterized in that, preceding or following the at least one curtain applicator in the material-web course, the material web (18) passes at least one further curtain applicator (10') which dispenses the application medium from a dispensing-opening arrangement, in particular a slit nozzle or a sliding coating nozzle, in the form of a curtain under the influence of gravity and optionally the influence of further forces towards the associated the same or, preferably, another surface of the material web in a further application section (16') of the material-web course, which application section (16') runs substantially horizontally or in a curved manner in accordance with a radius of a deflecting and supporting roller of the curtain applicator or has at least one movement speed component which is greater in the horizontal direction than in the vertical direction, the material web passing, in at least one further drying section of the material course which follows the further application section, the or at least one contactless drying device (24'; 30') which subjects the application medium to a thermal action, in order to dry the applied application medium at least partially; and, in the course and/or at the end of the further application section, the material web being diverted by at least one deflecting angle by way of a further first deflecting arrangement (20') which possibly comprises the deflecting and supporting roller (if present), in such a way that, after the deflection, the material web at least initially runs substantially vertically downwards at least in a further first section of the material-web course which follows the said deflecting arrangement directly, or has a greater movement speed component in the vertical direction downwards than before the deflection.
14. Machine according to Claim 13, characterized in that the further first section of the material-web course which directly follows the deflection in the course and/or at the end of the further application section (16') is the or a further drying section, in which the material web passes the or at least one contactless further drying device (24') which subjects the application medium to a thermal action.
15. Machine according to Claim 13 or 14, characterized in that the material web is fed after the deflection in the course and/or at the end of the further application section (16') to the/a further drying device (24'), which subjects the application medium to a thermal action, of the/a further drying section, in such a way that the thermal action of the further drying device on the application medium begins at a lower level with respect to the further application section (16').
16. Machine according to Claim 14 or 15, characterized in that, after the deflection in the course and/or at the end of the further application section, in particular in the further drying section or further first section and, if desired, in an adjoining further second section and/or further third section of the material-web course, the material-web course corresponds to the teaching of at least one of Claims 3 to 12.
17. Machine according to one of Claims 14 to 16, characterized in that sections or part sections of the material-web course after the application section (16) and after the further application section (16') provide movement speed components of the material web (18) in mutually opposed horizontal directions.
18. Machine according to Claim 17, characterized in that sections or part sections of the material-web course after the application section (16) and after the further application section (16') provide substantially parallel guidance of the material web with respect to one another with movement speed components of the material web (18) in mutually opposed horizontal directions.

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