EP2157239A1 - Device for creating coated paper, cardboard or other strips of fibrous material with at least one thermo-sensitive layer and method for operating such a device - Google Patents

Abstract

The device comprises coating units, drying systems, a web turning apparatus arranged in connection between two means (7, 8) forming function layers under formation of a first web guiding path, and means (15) for bypassing the web turning apparatus arranged between the means forming the function layers under formation of a second web guiding path. The means for bypassing the web turning apparatus comprises conducting- and/or guiding elements for guiding carrier webs that are arranged and implemented in order to produce a branching (11) in the web guidance behind the first function layer. The device comprises coating units, drying systems, a web turning apparatus arranged in connection between two means (7, 8) forming function layers under formation of a first web guiding path, and means (15) for bypassing the web turning apparatus arranged between the means forming the function layers under formation of a second web guiding path. The means for bypassing the web turning apparatus comprises conducting- and/or guiding elements for guiding carrier webs that are arranged and implemented in order to produce a branching (11) in the web guidance behind the first function layer under formation of a bypass for web turning apparatus and a junction (13) of the both web guidance path before the means forming second function layer. The coating units and the drying systems are formed and arranged in the means forming function layers in such a way that the carrier web is freely implemented by a return of the curve direction in longitudinal direction of the device observed within the means forming function layers. The coating units and the drying systems are arranged in means forming function layers in a horizontal plain or in a vertical plain. The curtain coating tool comprises coating nozzles extending itself in breadth-direction of the carrier web. The coating nozzle is connected over a coating medium supply with a coating medium supply system (16). An individual curtain coating tool is assigned two coating medium supply system for different coating mediums, which are alternatively coupled. The coating medium supply system consists of a thermosensitive coating medium. The drying systems of the means forming function layers comprise a coating unit, which is formed as hot air drying unit. An independent claim is included for a method for the production of coated paper, cardboard or other fiber material web.

Description

The invention relates to a device for producing coated paper, cardboard or other fibrous webs with at least one thermosensitive layer as a functional layer by applying at least one liquid or pasty thermosensitive coating medium on a carrier web by means of a function layer forming unit comprising at least one applicator and one of these downstream drying section.

The invention further relates to a method for operating a device for producing coated paper, cardboard or other fibrous webs with at least one thermosensitive layer.

The invention is suitable in addition to said paper, cardboard or other fibrous webs for other than recording medium suitable webs, such as films or textile substrates, which should have a thermosensitive layer on one or both sides.

A thermosensitive layer is understood to mean a coating layer which is suitable for imaging visually detectable information by discoloration on exposure to heat, in particular contact with a heatable writing head. This comprises at least a color former, a color developer and a binder.

• La papeterie 275, Avril-Mai 2006, S. 6-14 und
• Revue de Papier Carton No. 85, Fevrier-Mars 2006, S. 34-37

vorbekannt. Dabei ist der Aufragseinrichtung in Form des Vorhangauftragswerkes eine Trockenstrecke nachgeordnet. Zur Vermeidung eines Einrollens wird zur Flachlagekorrektur auf der Rückseite Wasser aufgetragen. Mit einer derartigen Grundkonfiguration kann eine einzige thermosensitive Schicht aufgetragen werden. Weiterentwicklungen auf dem Gebiet der Thermopapiere und die Erweiterung des Anwendungsspektrums haben zur Entwicklung hochqualitativer Thermopapiere geführt. Diese sind entweder beidseitig mit einer thermosensitiven Beschichtung versehen oder aber weisen über der thermosensitiven Schicht noch eine Deckschicht als Schutzschicht auf. Um diese zusätzlichen Funktionsschichten zu erzielen, sind entsprechend der Anzahl der einzelnen Schichten Funktionsschichten bildende Einheiten vorzusehen, umfassend Auftragseinrichtungen mit diesen zugeordneten Auftragsmedienbereitstellungssystemen, denen eine Trockenstrecke nachgeordnet ist, um den erforderlichen Trockengehalt zu gewährleisten. Derartige Vorrichtungen sind jedoch durch einen erheblichen Bauraumbedarf charakterisiert und aufgrund der Vielzahl Funktionsschichten bildender Einheiten kostenintensiv. Je nach herzustellender Art der beschichteten Faserstoffbahn werden einzelne Auftragseinrichtungen und die nachgeordneten Trockenstrecken jedoch nicht benötigt, so dass über große Teile des gesamten Betriebsbereiches Überkapazitäten vorgehalten werden und die Vorrichtung nicht optimal genutzt wird.Devices for producing coated paper, cardboard or other fibrous webs with at least one thermosensitive layer in the form of thermal papers by application of a liquid or pasty thermosensitive Application medium on a carrier web by means of a curtain applicator are exemplary

• La papeterie 275, Avril-Mai 2006, pp. 6-14 and
• Revue de Papier Carton no. 85, Fevrier-Mars 2006, pp. 34-37

previously known. In this case, the Aufragseinrichtung is arranged downstream of a drying section in the form of curtain applicator. To avoid curling, water is applied to the flatness correction on the reverse side. With such a basic configuration, a single thermosensitive layer can be applied. Further developments in the field of thermal papers and the extension of the range of applications have led to the development of high-quality thermal papers. These are either provided on both sides with a thermosensitive coating or have over the thermosensitive layer nor a cover layer as a protective layer. In order to achieve these additional functional layers, functional layers forming units are to be provided according to the number of individual layers, comprising application devices with associated application media supply systems, downstream of which a drying section is arranged in order to ensure the required dry content. However, such devices are characterized by a considerable space requirement and cost-intensive due to the large number of functional layers of forming units. However, depending on the type of coated fibrous web to be produced, individual application devices and the downstream drying sections are not required, so that overcapacities are kept available over large parts of the entire operating range and the device is not optimally utilized.

The invention is therefore based on the object, a device for the production of coated paper, cardboard or other fibrous webs, in particular in the form of thermal paper to develop such that the disadvantages of the prior art are avoided. The device should be characterized by a structurally simple structure with a low number of components and be suitable for a carrier web both one-sided multiple, in particular to coat twice or provided on both sides with at least one coating. A change to the different types of coated paper, cardboard or other fibrous webs should be possible with little control engineering effort and free of retooling promptly on request.

The solution according to the invention is characterized by the features of claims 1 and 13. Advantageous embodiments are described in each case in the subclaims.

A device for producing coated paper, cardboard or other fibrous webs with at least one thermosensitive layer as a functional layer is characterized in that it comprises only two successive switchable, each forming at least one functional layer units, wherein in the connecting region between the two functional layer-forming units a web turning device to form a first Bahnführungsweges and means for bypassing the web turning device to form a second Bahnführungsweges for the carrier web between the two functional layers forming units are provided.

The inventive device is characterized by the provision of only two functional layers forming units, which are suitable by the intelligent arrangement and control of their operations to produce a variety of different types of coated paper, cardboard or other fibrous webs with little effort, free of a conversion of Contraption. There is thus the possibility of a timely change with optimum utilization of the individual components of the individual functional layers forming units.

The means for bypassing the web turning device comprise in the simplest case guide and / or guide elements for the guidance of the carrier web, which are arranged and designed to be suitable, a branch in the Web guide behind the first functional layer-forming unit to form a bypass to the web turning device and to bring together the two web guide paths in front of the second functional layer-forming unit. Due to the formation of two parallel guide paths, the connection area can be made relatively short and compact, which has a favorable overall effect on the required space requirement of the device.

The application device and the drying section in a functional layer-forming unit are designed and arranged so that the carrier web within the functional layer-forming unit is considered free from a change of direction in the longitudinal direction of the device or is guided free of a reversal of the chosen direction of curvature, it being ensured that the coated surface is subjected to a secondary drying.

With regard to the arrangement and alignment of the components of the functional layer-forming units to each other, there are basically two options. According to a first embodiment, these are preferably in a common horizontal plane, i. arranged offset from each other in the vertical direction. According to a second embodiment, the arrangement with offset in the vertical direction to each other. The first embodiment forms a very compact unit in terms of extent in the height direction, while the second embodiment allows adaptation to space conditions or the trajectory.

The arrangement of the individual functional layers forming units can be done in various ways. According to a first embodiment, the two functional layers forming units are arranged in such a way and viewed in the longitudinal direction of the device, that when guiding the carrier web in the connecting region between the two functional layers forming units on the second Bahnführungsweg the guiding direction of the carrier web in the longitudinal direction of the device free from a change of direction is.

For this purpose, the two functional layer-forming units are preferably arranged in a horizontal plane.

According to a further embodiment, the arrangement of the functional layer-forming units viewed in the direction of travel of the carrier web takes place behind one another such that when guiding the carrier web in the connection region between the two functional layers forming units on the second Bahnführungsweg the guiding direction of the carrier web of the device by at least one direction change in the longitudinal direction of the device is characterized. The intended direction change allows an arrangement in vertically offset planes, wherein the offset in the longitudinal direction between the two functional layer-forming units can be minimized. The second embodiment is characterized by a high degree of compactness in the longitudinal direction while optimally utilizing space in the vertical direction. In a particularly advantageous further development of the second embodiment, the arrangement of the unit forming the second functional layer spatially in the longitudinal direction of the device takes place completely in the region of the extension of the first functional layer-forming unit.

The two web guiding paths of the connecting region can be arranged downstream of the device of a unit forming the functional layer, wherein the two web guiding paths of the connecting region can be aligned in the horizontal direction or else in the vertical direction. The concrete execution takes place depending on the available installation space.

The application device of the individual functional layer-forming unit comprises a multi-layer curtain applicator, which allows an application of application medium in the form of a free one-layer or multi-layer curtain produced at a trailing edge. For this purpose, the curtain applicator unit comprises at least one applicator nozzle extending in the width direction of the carrier web, which has at least over a job media feeder is connected to a job media delivery system. The nozzle can be formed in a known manner as a slot die or slide die.

In a particularly advantageous further development, at least two application media supply systems can be provided for fast switching between different types of coating, which can be accessed alternately depending on the requirements of the application medium, for example by selectively coupling the application media supply with different application media delivery systems.

The single drying section of a functional layer-forming unit comprises at least one drying device. This can be in the form of a contactless drying, in particular hot air drying device, which is gas or steam heated is formed. Other drying systems, such as infrared drying are conceivable. The drying section is designed as a function of the dry content of the layer applied with the upstream application device. The drying section is preferably straight, but may also be characterized by a curved or other course.

For continuous operation, the carrier web is usually unrolled from a fibrous web roll and pulled through the device by means of appropriate pulling devices. Subsequent to the second functional layer-forming unit, the winding of the coated fibrous web takes place by means of a take-up device.

Can be applied as functional layers in addition to thermosensitive layers and other layers, such as cover layers in the form of protective layers. The latter are characterized by a lower basis weight in the range of 1 to 6 g / m ² than the thermosensitive layers, whose basis weight is preferably selected in the range of 2 to 7 g / m ² .

The inventive method for operating a device for producing coated paper, cardboard or other fibrous webs with at least one thermosensitive layer as a functional layer by applying liquid or pasty thermosensitive coating media on a carrier web is characterized in that it is operable in different modes, said in a first mode of operation, only one of the functional layer-forming units is activated, in a second mode of operation, the carrier web between two functional layer-forming units is guided over the first Bahnführungsweg and in a third mode, the carrier web between two functional layer-forming units is guided over the second Bahnführungsweg. Depending on the arrangement of the individual functional layers forming devices to each other can be done in the second mode via the web turning device a change in orientation of the top and bottom of the carrier web between the two functional layers forming units such that in the second functional layer forming unit either the same side as in the first functional layer-forming unit or the opposite side is coated.

The solution according to the invention is particularly suitable for the production of thermal paper. However, it can also be used for other web-form materials suitable as recording media, such as films or textile materials.

Figuren 1a bis 1c

verdeutlichen anhand eines Querschnittes den Aufbau unterschiedlicher Arten von beschichteten Papier-, Karton- oder andere Faserstoffbahnen;

Figur 2

verdeutlicht in schematisiert vereinfachter Darstellung den Grundaufbau und die Grundfunktion einer erfindungsgemäßen Vorrichtung zur Bereitstellung beschichteter Papier-, Karton- oder anderer Faserstoffbahnen mit mindestens einer Funktionsschicht;

Figuren 3a bis 3c

verdeutlichen in schematisiert vereinfachter Darstellung eine erste Ausführung einer erfindungsgemäßen Vorrichtung zur Bereitstellung beschichteter Papier-, Karton- oder anderer Faserstoffbahnen mit mindestens einer Funktionsschicht ,

Figuren 4a bis 4c

verdeutlichen in schematisiert vereinfachter Darstellung eine zweite Ausführung einer erfindungsgemäßen Vorrichtung zur Bereitstellung beschichteter Papier-, Karton- oder anderer Faserstoffbahnen mit mindestens einer Funktionsschicht,

The solution according to the invention is explained below with reference to figures. It details the following:

FIGS. 1a to 1c

illustrate the structure of different types of coated paper, cardboard or other fibrous webs by means of a cross-section;

FIG. 2

illustrates in a schematic simplified representation of the basic structure and the basic function of a device according to the invention for Providing coated paper, cardboard or other fibrous webs with at least one functional layer;

FIGS. 3a to 3c

illustrate in a schematic simplified representation of a first embodiment of a device according to the invention for providing coated paper, cardboard or other fibrous webs with at least one functional layer,

FIGS. 4a to 4c

illustrate in a schematic simplified representation of a second embodiment of a device according to the invention for providing coated paper, cardboard or other fibrous webs with at least one functional layer,

The FIGS. 1a to 1c show schematically greatly simplified in each case a cross section through a coated fibrous web 10, in particular in the form of thermal paper and possible basic versions of these, as they can be provided with the device 1 according to the invention. The fibrous web 10 or F is a carrier web T, which is preferably in the form of a paper web and which is characterized by a functional layer on at least one surface, ie upper side 2 and / or lower side 3.

In this case, a layer is understood to be a medium applied uniformly over the entire surface of the fibrous web F and forming a unit by drying or other processes with the fibrous web F.
The fibrous web 10 is characterized in an XYZ coordinate system by an extent in the longitudinal and width directions, which correspond to the X and Y directions and by a height Z. The cross section illustrates the representation in the YZ plane.

The FIG. 1a illustrates an embodiment of the coated fibrous web 10 in the form of a one-sided simply coated thermal paper. Recognizable here the functional layer in the form of the thermosensitive layer 4 on the upper side 2 of the fibrous web F acting as the carrier web T.

With regard to the specific embodiment of the thermosensitive layer 4, there are a number of possibilities. This includes at least a color former and a color developer. These disperse in a binder that does not or only insubstantially melts during heat development.

The FIG. 1b illustrated by a cross-section according to FIG. 1a a further embodiment of the coated fibrous web 10, in which in addition to the thermosensitive layer 4, a further protective layer in the form of a cover layer 5 is applied to this. This is usually a transparent layer. Such a coated fibrous web 10 in the form of thermal paper is also referred to as single-sided double-coated thermal paper.

In contrast, illustrates the Figure 1c by way of example with reference to a cross-section of a thermal paper coated on both sides as a coated fibrous web 10, which is characterized on the upper side 2 and the lower side 3 by a functional layer in the form of a thermosensitive layer 4, 6. Again, the individual thermosensitive layers 4 and 6 completely cover the surfaces formed on the upper and lower sides 2, 3.

To those in the FIGS. 1a to 1c According to the invention, corresponding devices 1 for coating or finishing surfaces according to the invention, as shown in FIG. 2, can be produced simply and inexpensively in different types of coated paper, board or other fibrous webs 10, in particular in the form of thermal papers FIGS. 2 to 4 used. These serve to apply at least one thermosensitive layer 4, 6 to one side of a carrier web T.

The FIG. 2 illustrates in a schematic simplified representation based on a view from the right of the basic structure of an inventive device 1 for producing coated paper, cardboard or other fibrous webs 10 with at least one functional layer in the form of a thermosensitive layer 4, or 6, which is constructed and arranged in that it is also suitable for producing a plurality of layers, in particular a double layer, on a surface of a carrier web T or fibrous web F or to produce a double-sided coated fibrous web 10.
The device 1 is assigned a coordinate system. In this, the X-direction describes the longitudinal direction of the device 1, in which the carrier web is moved through this and which is also referred to as the machine direction. The Y direction describes the width direction and the Z direction the height direction. The apparatus 1 comprises for producing the different types of coated paper, cardboard or other fibrous webs 10 according to one of FIGS. 1a to 1c a total of only two functional layers forming units 7 and 8, which are connected in the direction of passage of the carrier web to be coated T in the form of the fibrous web F and between a unwinding device 9 for unwinding the carrier web T of a fibrous web roll and a winding device 12 for winding the then coated fibrous web 10th are arranged. Each of the individual functional layers forming units 7, 8 comprises at least one applicator A1, A2, which is formed in the form of a so-called multi-layer curtain applicator CC1, CC2 with at least two applicator nozzles. Each applicator A1, A2 is arranged downstream of a drying line TS1 and TS2. Application device A1, A2 and drying section TS1, TS2 of each functional layer forming unit 7, 8 and the associated means for guiding the carrier web T, usually guide and guide rollers are arranged such that applicator A1 and drying line TS1 or A2 and TS2 successively the same side of the carrier web T, in particular fibrous web F become effective. The guidance of the carrier web within the functional layer-forming devices 7, 8 takes place freely from a change in direction in the machine direction considered or free from a reversal of the direction of the curve. Between the two functional layers forming units 7 and 8, a web turning device 14 is provided. This allows a reversal of the carrier web T, which includes a change of orientation between top 2 and bottom 3 of the carrier web T, so that now in the subsequent functional layer forming unit 8, the bottom 3 of the applicator A2 faces. Further, means 15 for bypassing the web turning device 14 are provided, which are designed in the form of a so-called bypass. This is realized in that between the two functional layers forming units 7 and 8 in the web guide a branch 11 is provided, which is a continuation between the two functional layers forming units 7 and 8 in a first Bahnführungsweg I via the web turning device 14 or a second Bahnführungsweg II in direct connection to the subsequent functional layer-forming unit 8 allows.

In each of the functional layer forming units 7 and 8, a pulling device Z1 and Z2 is preferably also provided. This allows a movement of the carrier web T to be coated fibrous web F through the device 1 therethrough.

When in the FIG. 2 1, both functional layer-forming units 7 and 8 are arranged one after the other in the horizontal direction in the longitudinal direction of the device 1, wherein the arrangement in the illustrated case preferably takes place in a horizontal plane which is defined by an extension in X and Y. Direction can be characterized. The in the FIG. 2 illustrated embodiment is characterized by a uniform directional course for the transport direction of the fibrous web F to be coated by the two functional layers forming units 7, 8 of the device 1. The fibrous web F to be coated does not undergo any transport direction reversal between the unwinding device 9 and the winding device 12, even after passing through the web turning device 14.

The application device A1, A2, is designed as a multi-layer curtain applicator for dispensing at least two coating layers. Such commissioned works are already known in different versions. These comprise at least two applicator nozzles extending over the machine width, that is to say in the Y direction. These curtain coater can be formed both in the form of a slot nozzle, which can also be configured as a Twindüse or Tandemdüse, as well as in the form of a Gleitschichtdüse, comprising at least two extending over the machine width exit column, which are each coupled to a vertically inclined supply channels, formed ,

From the respective application nozzle, the application medium falls on a trailing edge in free fall to form a curtain on an underlying moving carrier web T or the fibrous web F. The order can be done directly through the nozzle in free fall on the corresponding surface of the moving fibrous web F or but almost indirectly via a sliding plate arranged therebetween, where the application medium is applied via the nozzle and which also forms a trailing edge in the flow direction of the application medium for producing a curtain of application medium.

In the case of the slot nozzle mentioned above, the tear-off edge is formed at its outlet opening. Under the trailing edge is always understood the line at which the application medium passes into free fall.

Each curtain applicator unit further comprises at least one application media feed, which is indicated by an arrow and via which the application nozzle is supplied with application medium from an application media supply system 16, 17. In a particularly advantageous further development, the curtain applicator CC2 can be connected to its application nozzle of the second functional layer-forming unit 8 with at least two application media supply systems 17 and 18.

With the device 1 according to the invention different modes of operation are conceivable, which are used to produce the coated paper, cardboard or other fibrous webs 10 according to the FIGS. 1a to 1c lead and essentially differ only by the type of carrier web guide in the connection region between the two functional layer forming units 7, 8 and the activation / deactivation of these.

To comply with the execution FIG. 2 a coated fibrous web 10 according to FIG. 1a In a first mode of operation, only the first functional layer-forming unit 7 is activated. The fibrous web F undergoes an order on the upper side 2 by means of the process applicator CC1. The web F is then fed to the drying section TS1 and, after passing through it, passed through the non-activated unit 8 forming the second functional layer via the pulling device Z1.

Not activated means that the drying section TS2 is deactivated and furthermore no application medium is applied via the curtain applicator CC2. In the simplest case, the order media supply to the commissioned work CC2 is interrupted.

To obtain a single-sided double-coated fibrous web 10 according to FIG. 1b With a thermosensitive layer 4 on the upper side 2 and a cover layer 5 arranged above it in the form of a protective layer, the fibrous web F is guided in a second mode of operation by units 7 and 8 which are both functional layer-forming units. In this case, the fibrous web is guided in the connection region via the second Bahnführungsweg II in the bypass to web turning device 14, that is, there is no change in the orientation of top 2 and bottom 3 and the second functional layer, which is preferably applied in the form of the cover layer 5 as a protective layer , is then applied to the already existing functional layer in the form of the thermo-sensitive layer 4 via the second curtain applicator CC2. This is followed by curing at Passing through the drying section TS2, wherein the coated fibrous web 10 is rolled up after reaching the required dry content.

To a coated fibrous web 10 according to Figure 1c in the form of a double-sided simply coated fibrous web 10, the device 1 is operated in a third mode of operation such that the fibrous web F passes through both functional layers forming units 7 and 8, but between the two units 7 and 8, the fibrous web F on the web turning device 14 is guided along the web guide path I and thus the orientations of top and bottom 2, 3 are reversed, so that at the second functional layer forming unit 8 now has the bottom 3 to the applicator CC2 and the order is placed on this.

The design of the dry lines TS1 and TS2 can be done in many forms. In the simplest case, at least one drying device is arranged in each drying section TS1, TS2, which in the simplest case according to FIG FIG. 2 in each case comprises at least one contactless drying device, in particular a hot air drying device HLT1 and HLT2. This is either gas or steam heated.

Clarifies the FIG. 2 the basic principle, shows FIG. 3a an example of a possible embodiment in the form of a further development of FIG. 2 , In this case, the individual devices can be arranged one behind the other in a horizontal plane or in horizontal planes offset from each other. The functional layers forming units 7 and 8 here also each comprise a multi-layer process applicator CC1 and CC2 with at least two application nozzles and a downstream this drying section TS1 and TS2, wherein the individual drying lines TS1 and TS2 each by a plurality of successively connected drying devices in the form of Hot air dryers HLT1.1 to HLT1.3 or HLT2.1 to HLT 2.3 are characterized. These are preferably connected in series and arranged at an angle to each other, so that the available space in vertical direction when installing a correspondingly large drying capacity used in an optimal manner and the space requirement in the axial direction, ie in the machine direction despite series connection of the functional layer forming units 7, 8 can be kept as low as possible.

The FIG. 3b illustrates the operation of the device 1 in producing a coated fibrous web 10 in the form of a single-sided double-coated fibrous web F. Shown are the individual process steps based on a cross-section through a fibrous web F for the individual layering you the position of the individual sides of the fibrous web F is recognizable here that is applied via the first coater CC1, the first functional layer in the form of the thermosensitive layer 4 on the surface 2 of the carrier web in the form of the fibrous web F and the fibrous web F without orientation change between the top and bottom 2, 3 to the second functional layer-forming unit. 8 wherein the second functional layer-forming unit 8 is used here for the application of the covering layer 5 functioning as a protective layer. The leadership is in this case on the Bahnführungsweg II, which in FIG. 3a shown here by a broken line. In contrast, illustrates the Figure 3c The production of a coated fibrous web 10 in the form of a double-sidedly coated fibrous web F. It can be seen that the two sides - top and bottom 2 and 3 - after passing through the second functional layer-forming unit 8 are coated. This is realized by the guide over the Bahnführungsweg I in the form of the web turning device 14, whereby a change in orientation between top 2 and bottom 3 is generated, which means that now the order on the present of a coating underside 3 in the second functional layer forming unit 8 takes place. This change of orientation is via the arrows in Figure 3c clarified.

The in the Figures 2 and 3 illustrated connecting portions between the two functional layers forming means 7 and 8 are preferably arranged and designed such that by the web turning device 14th and the associated bypass 15 recordable web guide paths I and II are preferably aligned parallel to each other.

In the FIG. 3a embodiment shown is preferably characterized by three pulling devices Z1 to Z3. The two drawbars Z1 and Z2 are as in FIG. 2 downstream of the two functional layers forming units 7, 8. A further pulling device Z3 is arranged behind the junction 13 and before the application device A2 of the second functional layer-forming unit 8.

Opposite in the Figures 2 and 3 illustrated embodiments illustrates the FIG. 4a by way of example a further embodiment, in which the arrangement of the individual functional layer-forming units 7 and 8 takes place in different vertical planes, wherein in addition a change of direction in the web guide is achieved. In the case shown, the two functional layer-forming units 7 and 8 are preferably arranged one above the other in the vertical direction, so that the machine-direction machine length which describes the X-direction can be made relatively short. The space in the vertical direction can be optimally used. The arrangement of applicators A1, A2 and the drying lines TS1 and TS2 is such that the carrier web T in the form of the fibrous web F to be coated passes through the individual functional layer forming units 7 and 8 in the opposite direction as viewed in the longitudinal direction of the device 1. Preferably, the connecting region is assigned to one of the two functional layers forming units 7 or 8 and arranged with this in a plane. The passage is still in the same direction as in the arranged in the same plane functional layer unit.

In the case shown, the connecting region of the functional layer-forming device 7 is preferably arranged directly downstream, wherein the fibrous web F functioning as the carrier web T still remains unaltered therein Direction enters. However, it is also conceivable that the displacement in the vertical direction in the overlying second functional layer forming unit 8 or upstream of this. The concrete structural design is dependent on the application requirements. The basic structure of the two functional layers forming units 7 and 8 corresponds to that in the Figures 2 and 3 Therefore, the same reference numerals are used for the same elements. In this case as well, preferably the individual drying sections TS1 and TS2 each comprise a plurality of individual drying devices connected in series in series, here in the form of hot-air drying devices HLT1.1 to HLT 1.3 or HLT2.1 to HLT2.3, successively on the fibrous web F or F or passing through them be effective on these passing fibrous web F.

Opposite in the Figures 2 and 3 illustrated embodiments with a constant direction of passage for the fibrous web F to be coated by the device 1 is the embodiment in FIG. 4a Characterized in that already alone due to the arrangement, which causes a change in direction of the leadership of the fibrous web F, a change in orientation in Bahnführungsweg 2 between the top 2 and the bottom 3 is generated. In this embodiment, to maintain the same orientation of upper side 2 and lower side 3, the fibrous web F now has to be guided over the web turning device 14, while otherwise in the bypass to the web turning device 14 an orientation reversal between upper side 2 and lower side 3 with respect to the unit 8 forming the next functional layer automatically occurs he follows. Accordingly, when guided over the Bahnführungsweg 2 successively on the functional layers forming units 7 and 8 according to FIG. 4b a simple two-sided coated fibrous web 10 are generated. In order to obtain a double-coated fibrous web 10 on the one side, it is correspondingly Figure 4c necessary to guide the fibrous web F over the web turning device 14, in particular the first web guide path I. In this case, the thermosensitive layer 4 is applied in the first functional layer-forming unit 7 via the first curtain applicator CC1 on the upper side 2 of the fibrous web F, which passes through the drying line TS1 after the curtain applicator CC1 and now in the connection region to the second functional layer forming unit 8 is guided over the web turning device 14, so that now a reversal in the orientation between top and bottom 2, 3 takes place and thus the top 2 again with a further layer, preferably a cover layer 5 is coated.

It should be added that in the case of an order of only one layer on one side of the web, only one application slot or only one delivery nozzle of the multi-layer applicator is activated. With several desired layers correspondingly more nozzles or feed are activated.

The solution according to the invention is not on in the FIGS. 2 to 4 limited embodiments shown. This allows at least the application of two layers with a single applicator, the nature of the order is variable here and is determined only by the operation of the device 1 and the application medium applied via the applicator. Furthermore, simple single-sided coated fibrous webs F with the respective device 1 in a simple manner can be produced.

LIST OF REFERENCE NUMBERS

1

Device for producing a coated fibrous web

2

top

3

bottom

4

thermosensitive layer

5

topcoat

6

thermosensitive layer

7

Functional layer-forming unit

8th

Functional layer-forming unit

9

unrolling

10

coated fibrous web

11

branch

12

takeup

13

together

14

Web turning device

15

Means for bypassing the web turning device

16

Order media delivery system

17

Order media delivery system

18

Order media delivery system

I

first pathway

II

second track guidance path

A1

applicator

A2

applicator

CC1

Vohangauftragswerk

CC2

Curtain applicator

HLT1.1 - HLT1.3

Hot air drying device

HLT2.1 - HLT2.3

Hot air drying device

TS1

drying section

TS2

drying section

X

longitudinal direction

Y

width direction

Z

height direction

F

Fibrous web

T

support web

Claims (13)

Device (1) for producing coated paper, cardboard or other fibrous webs (10) with at least one thermosensitive layer (4, 6) as a functional layer by application of a liquid or pasty thermosensitive coating medium on a carrier web (T) by means of a functional layer forming Unit (7, 8), comprising at least one application device (A1, A2) and a downstream drying section (TS1, TS2),
characterized,
that two successive switchable, each having at least one functional layer forming units (7, 8) are provided, forming in the connecting region between the two functional layer units (7, 8) has a web turning device (14) to form a first web guide path (I) and means (15 ) are provided for bypassing the web turning device (14) to form a second web guide path (II) for the carrier web (T) between two functional layers forming units (7, 8). Device (1) according to claim 1,
characterized,
in that the means (15) for avoiding the web turning device (14) comprise guide and / or guide elements for the guidance of the carrier web (T), which are arranged and designed to be suitable for a branch (11) in the web guide behind the web guide first functional layer forming unit (7) forming a bypass to the web turning device (14) and a merging (13) of the two web guide paths (I, II) in front of the second functional layer forming unit (8) to produce. Device (1) according to one of claims 1 or 2,
characterized,
that the applicator (A1, A2) and the drying section (TS1, TS2) forming a functional layer unit (7, 8) are configured and arranged such that the carrier web (T) is free from a reversal of the chosen curve direction in the longitudinal direction of the device (1), within the functional layer forming unit (7, 8) is guided. Device (1) according to claim 3,
characterized,
that the applicator (A1, A2) and the drying section (TS1, TS2) in a functional layer forming unit (7, 8) are arranged in a horizontal plane. Device (1) according to claim 3,
characterized,
in that the application device (A1, A2) and the drying section (TS1, TS2) are arranged in a functional layer-forming unit (7, 8) in planes which are offset from each other vertically. Device (1) according to one of claims 1 to 5,
characterized,
are that the two functional layers forming units (7, 8) in the longitudinal direction of the device (1) arranged behind one another viewed. Device (1) according to claim 6,
characterized,
that both the functional layer forming units (7, 8) are arranged in a horizontal plane. Device (1) according to claim 6,
characterized,
arranged that the two functional layers forming units (7, 8) displaced in the vertical direction to each other. Device (1) according to at least one of the preceding claims,
characterized,
in that the curtain applicator unit (CC1, CC2) comprises at least one application nozzle extending in the width direction of the carrier web (T), which is connected via at least one application media feed to a coating media supply system (16, 17, 18). Device (1) according to claim 9,
characterized,
in that at least one individual application unit (CC2) is assigned at least two application media supply systems (17, 18) for different application media, which can be coupled alternately, wherein at least one application media delivery system contains a thermosensitive application medium. Device (1) according to at least one of the preceding claims,
characterized,
in that the unit (7, 8) forming the single drying section (TS1, TS2) of a functional layer comprises at least one drying device (HLT1.1-HLT1.3, HLT2.1-HLT2.3). Device (1) according to claim 11,
characterized,
that the individual drying device (HLT1.1-HLT1.3, HLT2.1-HLT2.3) is designed as a hot-air drying device, which is steam-heated or gas-heated. Method for operating a device (1) for producing coated paper, board or other fibrous webs (10) with at least one thermosensitive layer (4, 6) as a functional layer by application of liquid or pasty thermosensitive application media to a carrier web (T) according to one of the preceding claims,
characterized,
that the device (1) forming, by controlling the web guidance and of the individual components of the functional layer units (7, 8) is operable in different modes of operation, wherein
In a first mode of operation, only one of the functional layer-forming units (7,) is activated, in a second mode both functional layer-forming units (7, 8) are activated and the carrier web (T) between two functional layer-forming units (7, 8) via the first web guide path (I) is guided and in a third mode of operation both functional layer-forming units (7, 8) are activated and the carrier web (T) between two functional layer-forming units (7, 8) via the second web guide path (II) is guided.

Images