DE102020116773A1 - Adhesive application system - Google Patents

Abstract

The present disclosure relates to an adhesive application system (100) for applying an aqueous adhesive to a paper or cardboard substrate (101), the paper or cardboard substrate (101) being displaceable relative to the adhesive application system (100) along a displacement direction (103). comprises an adhesive application device (105) which is designed to apply the aqueous adhesive to the paper or cardboard substrate (101), at least one plasma feed device (106, 111) and a control device (107) in which at least one adhesive application pattern is stored and which is designed to control both the adhesive application device (105) for applying the at least one adhesive application pattern and the at least one plasma supply device (106, 111) for activating the aqueous adhesive and/or for activating the paper or cardboard substrate (101). .

Description

The invention relates to an adhesive application system, in particular an adhesive application system and a method for applying an aqueous adhesive to a porous paper or cardboard substrate.

Conventional paper- or cardboard-based substrates are often bonded with aqueous dispersion adhesives in which polymers suitable for the formation of the adhesive layer are dispersed as solid particles in an aqueous dispersion medium. Here, the formation of the adhesive layer on the substrate takes place essentially through the absorption of the aqueous phase by the paper or cardboard-based substrate.

In the DE 10 2018 108 273 A1 discloses a method for connecting two packaging material layers by means of a coating agent with a thermoplastic material which is supplied in a plasma.

the DE 195 32 412 A1 discloses a method for the surface treatment of plastic materials with a plasma jet.

A disadvantage of the known devices and methods is that the use of plasma jets for surface treatment has so far only been able to be used advantageously for plastic materials and not for a porous paper or cardboard substrate, for example for the production of cardboard boxes.

Furthermore, in the known devices and methods, the use of adhesives based on synthetic materials is often disadvantageous for reasons of sustainability.

It is an object of the invention to provide an improved concept for applying aqueous adhesives to a paper or cardboard substrate.

According to a first aspect, the object is achieved by an adhesive application system for applying an aqueous adhesive to a paper or cardboard substrate, the paper or cardboard substrate being displaceable along a displacement direction relative to the adhesive application system. The adhesive application system here comprises an adhesive application device which is designed to apply the aqueous adhesive to the paper or cardboard substrate, at least one plasma supply device and a control device in which at least one adhesive application pattern is stored and which is designed, both the adhesive application device for applying the at least to control an adhesive application pattern as well as the at least one plasma supply device for activating the aqueous adhesive and / or for activating the paper or cardboard substrate.

A joint control of the adhesive feed device and the at least one plasma feed device by the control device offers the advantage that the user only has to enter the adhesive application pattern, such as the coordinates of the adhesive application on the product, length, width or quantity of the adhesive application per production order, once by the user, as this Data are used simultaneously for the intermittent control of the plasma supply device.

At least one adhesive application pattern is stored in the control device of the adhesive application system, on the basis of which the plasma feed device, the adhesive application device and in particular the further plasma feed device are controlled by the control device.

This has the technical advantage that the control device ensures that the desired adhesive application pattern is applied to the porous paper or cardboard substrate.

The paper or cardboard substrate is preferably a surface-rough and porous paper-based substrate.

In particular, the porous paper or cardboard substrate comprises a folding box blank, in particular made of solid cardboard with fresh fiber and / or recycled paper, or corrugated cardboard. The adhesive application system comprises, in particular, a folding box gluing machine which is designed to glue the folding box blank in order to form a carton from it.

In particular, the at least one plasma supply device is arranged in alignment behind the adhesive application device with respect to the direction of displacement of the paper or cardboard substrate and is designed, controlled by the control device, to activate the adhesive.

This achieves the technical advantage that by supplying plasma through the plasma supply device downstream of the adhesive application device to the applied adhesive, rapid activation of the adhesive can be ensured, so that the adhesive time, i.e. the time it takes for the adhesive to bond the porous paper - or cardboard substrate required, can advantageously be reduced, or an increased initial adhesion can be ensured.

Furthermore, the plasma supply device can be arranged and configured in alignment with the displacement direction of the paper or cardboard substrate in front of the adhesive application device, controlled by the control device, to supply plasma to the surface of the paper or cardboard substrate to be brought into contact with the aqueous adhesive in order to to accelerate an uptake of the aqueous phase of the aqueous adhesive by the paper or cardboard substrate.

The plasma feed device upstream of the adhesive application device is used to activate the substrate. The plasma supply device downstream of the adhesive application device is designed to supply plasma to the adhesive applied by the adhesive application device to the porous paper or cardboard substrate in order to activate the adhesive.

By supplying plasma through the plasma supply device upstream of the adhesive application device, the substrate is advantageously activated and, when aqueous adhesives are used, the penetration of the aqueous adhesive component into the substrate is accelerated by increasing the surface tension of the porous substrate. As a result of the accelerated absorption process, the adhesive applied to the activated substrate surface reaches its tackiness more quickly.

By reducing the gluing time, the displacement speed of the porous paper or cardboard substrate displaced along the displacement direction compared to the adhesive application system can be increased, so that the throughput of the adhesive application system can advantageously be increased.

A correspondingly advantageous activation of the aqueous adhesive and / or the substrate by plasma is particularly advantageous when using so-called bio-adhesives. Bio-adhesives correspond to adhesives based on biological substances. Bio-adhesives include, for example, starch, starch derivatives and / or other polysaccharides. Corresponding adhesives based on biological substances are preferred over traditional synthetic adhesives due to sustainability aspects, since advantages in terms of health compatibility, waste disposal and manufacturability can be achieved. This is because bio-adhesives often have better health compatibility than synthetic adhesives and, for this reason, waste disposal is improved. In addition, corresponding bio-plastics can be produced from biological, in particular renewable, materials, in particular from renewable raw materials.

The aqueous adhesive includes, in particular, an aqueous bioadhesive which is based entirely, that is to say 100%, on biological substances.

In aqueous bio-adhesives, however, the water content is often higher than in correspondingly synthetically produced aqueous adhesives, so that the solids content in corresponding aqueous bio-adhesives is lower than in correspondingly synthetically produced aqueous adhesives. In addition, when using bio-adhesives, e.g. adhesives based on starch derivatives, hygroscopic effects often occur, which can impair quick bonding under certain circumstances.

By supplying plasma to the aqueous bioadhesive applied to the substrate, the corresponding disadvantageous effects are counteracted and thus a particularly advantageous bond is achieved.

In particular, the position of the plasma feed device, the adhesive application device, and in particular the further plasma feed device cannot be changed while the adhesive is being fed to the porous paper or cardboard substrate, so that the plasma feed device, the adhesive application device and, in particular, the further plasma feed device determine the feed direction of plasma, or adhesive cannot change.

In this case, the adhesive application pattern comprises, in particular, a sequence of adhesive dots and / or adhesive lines which are applied to the substrate by the adhesive application system when the substrate is displaced along the displacement direction. The control device controls the extent of the adhesive dots applied to the substrate or the length of the adhesive lines applied to the substrate by changing the time of application of the adhesive and the duration of the pauses between the individual application steps, in particular as a function the displacement speed of the substrate.

The plasma feed device is then controlled on the basis of the data of the adhesive application pattern and is only active in the areas in which adhesive is applied to the substrate. This has the advantage that the electrical energy required to control the plasma supply device is reduced. In addition, the Gas consumption of the plasma supply device is reduced, as a result of which the operating costs are reduced.

In addition, adhesive is often applied in recessed areas on the substrate that do not contain any image or text information. These areas can, for example, form a decorative exterior of the packaging. If the action of the plasma feed device is not limited to areas that are intended for the application of adhesive, it cannot be ruled out that printed or otherwise finished surfaces will be damaged by the action of the plasma feed device. Such damage can be avoided by a common control of both the adhesive application device for applying the at least one adhesive application pattern and the plasma supply device for activating the substrate and / or activating the adhesive.

Food packaging also often has a barrier coating which serves to prevent the packaging from becoming wet or the packaging components from migrating into the food. These barriers often have hydrophobic properties which can be adversely affected by the action of the plasma supply device. The exposure can also damage the barrier layer. The area where the packaging is glued is not regularly in contact with the food. If the action of the plasma supply device were not limited to this area of the application of the adhesive, there is always the risk of property-changing, negative influence on areas that may be in contact with the food. With a common control of both the adhesive application device and the plasma supply device, such a barrier coating can be specifically excluded from the supply of plasma in a simple and advantageous manner.

The displacement of the porous paper or cardboard substrate relative to the adhesive application system along the displacement direction can be ensured here, for example, by a conveyor belt, which can preferably also be controlled by the disruption device of the adhesive application system. Here, for example, the adhesive application system is arranged above the conveyor belt, so that a substrate positioned on the conveyor belt can advantageously be passed below the adhesive application system in order to apply the adhesive to the porous paper or cardboard substrate using the adhesive application device. Here, the aligned arrangement of the plasma supply device in the displacement direction behind the adhesive application device ensures that the adhesive applied to the substrate by the adhesive application device, when the substrate is subsequently displaced in the displacement direction, is shifted directly into the plasma jet supplied by the plasma supply device. This ensures that while the adhesive is being applied to the substrate, it is immediately activated by the plasma. The aligned arrangement of the plasma supply device in the displacement direction behind the adhesive application device thus ensures that the adhesive applied to the substrate by the adhesive application device is not guided past the plasma jet.

The aligned arrangement in front of the adhesive application device ensures that the adhesive is only applied to areas of the substrate, the supply of which has been activated by the plasma supply device.

In particular, the plasma supply device comprises an atmospheric pressure plasma nozzle which is designed to generate a plasma jet which is introduced into the ambient atmosphere at normal pressure and is directed onto the surface of the porous paper or cardboard substrate to be treated.

In particular, the plasma within the plasma supply device is produced from a working gas by applying a high-frequency high voltage between electrodes. Here, the working gas of the plasma supply device is supplied from a generator, in particular through a first line.

In an exemplary embodiment, the adhesive application system comprises a further plasma supply device, which is arranged in alignment with the displacement direction of the porous paper or cardboard substrate in front of the adhesive application device and is designed to plasma the adhesive to be brought into contact To feed the surface of the porous paper or cardboard substrate in order to accelerate an uptake of the aqueous phase of the aqueous adhesive by the porous paper or cardboard substrate. This further plasma supply device is also controlled by the control device.

This has the technical advantage that the plasma pretreatment of the surface of the porous paper or cardboard substrate prior to the application of the aqueous adhesive by the adhesive application device improves absorption of the aqueous phase of the applied aqueous adhesive, whereby the adhesive time can be reduced. The plasma pretreatment in particular increases the surface tension of the surface of the porous paper or cardboard substrate before the adhesive is applied, so that the aqueous phase can penetrate the substrate more quickly.

With corresponding aqueous bio-adhesives, which are based on biological substances, the water content is greater than with conventional synthetic aqueous adhesives, so that the porous paper or cardboard substrate has to absorb a larger amount of water and requires a longer time for this would increase the gluing time.

As a result of the plasma pretreatment by means of the further plasma supply device and the increase in the surface tension of the porous paper or cardboard substrate, the porous paper or cardboard substrate can absorb the water from the aqueous adhesive particularly quickly. This counteracts any prolongation of the bonding time when using aqueous adhesives based on biological substances.

Here, the further plasma supply device comprises in particular an atmospheric pressure plasma nozzle which is designed to generate a plasma jet which is introduced into the ambient atmosphere at normal pressure and is directed onto the surface of the porous paper or cardboard substrate to be treated.

Thus, the further plasma supply device is arranged in alignment with the displacement direction in front of the adhesive application device and is designed to supply the plasma to the surface of the porous paper or cardboard substrate as part of a plasma pretreatment in order to absorb the aqueous phase of the aqueous adhesive through the porous paper or cardboard Accelerate cardboard substrate.

Then, after the substrate has been displaced along the direction of displacement, the adhesive application device, which is arranged in alignment behind the further plasma supply device with respect to the direction of displacement, supplies adhesive to the surface pretreated by plasma.

Subsequently, after a further displacement of the substrate along the displacement direction, the plasma supply device arranged in alignment behind the adhesive application device with respect to the displacement direction feeds plasma to the adhesive applied to the substrate in order to activate the adhesive.

In an exemplary embodiment, the adhesive application system has a generator for the process fluid, in particular working gas, the plasma feed device, and in particular the further plasma feed device, the generator being fluidically connected to the plasma feed device in particular by a first generator line, and the generator in particular by a second generator line is fluidly connected to the further plasma supply device.

This achieves the technical advantage that a particularly advantageous supply of process fluid to the plasma supply device or to the further plasma supply device is made possible.

In an exemplary embodiment, the aqueous adhesive is an aqueous adhesive based on biological substances and the biological substances include, in particular, starch, starch derivatives and / or further polysaccharides.

This has the technical advantage that the use of an aqueous bioadhesive based on biological substances has adhesive properties comparable to synthetic adhesives, but can be obtained from renewable raw materials and is therefore advantageous from a sustainability perspective.

In particular, the aqueous adhesive based on biological substances also comprises lignin, cellulose, cellulose derivatives, latex and / or vegetable fillers.

In an exemplary embodiment, the adhesive application system has a holding device to which the adhesive application device and at least one plasma supply device are jointly attached. In particular, the adhesive application device and the at least one plasma supply device are attached at a fixed distance from one another.

This achieves the technical advantage that by using a common holding device after the adhesive application system has been repositioned, the adhesive application device, the plasma feed device and any further plasma feed device no longer have to be aligned with one another. This means that the control device does not need to reprogram the route conditions.

In an exemplary embodiment, the adhesive application system has a substrate detection device which is designed to detect the spatial extent or leading edge of the porous paper or cardboard substrate, the control device Control technology is connected to the substrate detection device, the adhesive application device, the plasma feed device and in particular the further plasma feed device and is designed, the adhesive application device, the plasma feed device and in particular the further plasma feed device depending on the detected spatial extent or the dimensions of the porous paper or cardboard stored in the control device. Control substrate. The substrate detection device can be designed as a light barrier.

For example, the beginning and the end of the substrate displaced along the direction of displacement are detected by the substrate detection device, the control device in particular determining the spatial extent of the substrate as a function of the detected time between the detected beginning and the detected end of the substrate displaced along the direction of displacement.

In particular, the control device is designed to control the adhesive application device, the plasma supply device and in particular the further plasma supply device as a function of the detected spatial extent of the porous paper or cardboard substrate and as a function of the displacement speed of the displaced porous paper or cardboard substrate.

• - Auftragen des wässrigen Klebstoffs auf ein Papier- oder Pappe-Substrat durch eine Klebstoffauftragsvorrichtung des Klebstoffauftragssystems,
• - Verlagern des Papier- oder Pappe-Substrats entlang einer Verlagerungsrichtung gegenüber dem Klebstoffauftragssystem, und
• - Aktivieren des durch die Klebstoffauftragsvorrichtung auf das Papier- oder Pappe-Substrat aufgetragenen Klebstoffs durch das Zuführen von Plasma durch eine in Bezug auf die Verlagerungsrichtung fluchtend hinter der Klebstoffauftragsvorrichtung angeordnete Plasmazuführungsvorrichtung des Klebstoffauftragssystems zu dem aufgetragenen Klebstoff.

According to a second aspect, the object of the invention is achieved by a method for applying an aqueous adhesive to a porous paper or cardboard substrate using an adhesive application system, the method having the following method steps:

• - Application of the aqueous adhesive to a paper or cardboard substrate by an adhesive application device of the adhesive application system,
• - Displacement of the paper or cardboard substrate along a displacement direction with respect to the adhesive application system, and
• - Activation of the adhesive applied by the adhesive application device to the paper or cardboard substrate by supplying plasma through a plasma feed device of the adhesive application system to the applied adhesive, which is arranged in alignment behind the adhesive application device with respect to the displacement direction.

This achieves the technical advantage that a particularly advantageous application of an aqueous adhesive to the paper or cardboard substrate is made possible.

• - Aktivieren der mit dem Klebstoff in Kontakt zu bringenden Oberfläche des Papier- oder Pappe-Substrats durch das Zuführen von Plasma einer weiteren Plasmazuführungsvorrichtung des Klebstoffauftragssystems zu der mit dem Klebstoff in Kontakt zu bringenden Oberfläche des Papier- oder Pappe-Substrats, wobei die weitere Plasmazuführungsvorrichtung in Bezug auf die Verlagerungsrichtung des Papier- oder Pappe-Substrats fluchtend vor der Klebstoffauftragsvorrichtung angeordnet ist.

In an exemplary embodiment, the method has the following method step, which is carried out before the aqueous adhesive is applied to the paper or cardboard substrate:

• - Activation of the surface of the paper or cardboard substrate to be brought into contact with the adhesive by supplying plasma from a further plasma supply device of the adhesive application system to the surface of the paper or cardboard substrate to be brought into contact with the adhesive, the further plasma supply device is arranged in alignment with the direction of displacement of the paper or cardboard substrate in front of the adhesive application device.

This achieves the technical advantage that an advantageous activation of the surface of the paper or cardboard substrate is ensured by the supplied plasma before the adhesive is applied.

In particular, the aqueous adhesive is applied to a paper or cardboard substrate, the applied adhesive is activated, and in particular the surface of the paper or cardboard substrate to be brought into contact with the adhesive is activated by a single control device based on at least one adhesive application pattern stored in the control device of the adhesive application system.

This achieves the technical advantage that the application of adhesive is advantageously controlled by the adhesive application pattern.

In an exemplary embodiment, a spatial extent or leading edge of the paper or cardboard substrate is detected by a substrate detection device, in particular by a light barrier, and the control of the adhesive application device, the plasma supply device and in particular the further plasma supply device is carried out by the control device as a function of the detected spatial Extension or leading edge of the paper or cardboard substrate.

According to a third aspect, the object of the invention is achieved by using an aqueous adhesive based on biological substances for application to a paper or cardboard substrate, the aqueous adhesive based on biological substances comprising in particular starch, starch derivatives and / or further polysaccharides.

This has the technical advantage that by using the on biological Substances-based aqueous adhesive an advantageous application of an aqueous adhesive to a paper or cardboard substrate takes place.

Embodiments of the invention are shown in the drawings and are described in more detail below.

• 1 eine perspektivische Darstellung eines Klebstoffauftragssystems zum Auftragen eines wässrigen Klebstoffs auf ein poröses Papier- oder Pappe-Substrat gemäß einem Ausführungsbeispiel; und
• 2 eine schematische Darstellung eines Verfahrens zum Auftragen eines wässrigen Klebstoffs auf ein poröses Papier- oder Pappe-Substrat gemäß einem Ausführungsbeispiel.

Show it:

• 1 a perspective view of an adhesive application system for applying an aqueous adhesive to a porous paper or cardboard substrate according to an embodiment; and
• 2 a schematic representation of a method for applying an aqueous adhesive to a porous paper or cardboard substrate according to an embodiment.

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which there is shown, by way of illustration, specific embodiments in which the invention may be practiced. It goes without saying that other embodiments can also be used and structural or logical changes can be made without deviating from the concept of the present invention. The following detailed description is therefore not to be taken in a limiting sense. Furthermore, it goes without saying that the features of the various exemplary embodiments described herein can be combined with one another, unless specifically stated otherwise.

The aspects and embodiments are described with reference to the drawings, wherein like reference characters generally refer to like elements. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more aspects of the invention.

1 shows a perspective illustration of an adhesive application system for applying an aqueous adhesive to a porous paper or cardboard substrate according to an embodiment.

An adhesive application system 100 comprises a folding box gluing machine which is designed to glue a folding box blank in order to form a carton therefrom. The porous paper or cardboard substrate 101 includes the folding box cut.

The folding box blank is a processed, flat packaging material blank, which is shaped or erected into a packaging material in a later processing step or is wrapped with the goods or packs. In particular, the porous paper or cardboard substrate is 101 a solid cardboard with fresh fiber and / or waste paper, or a corrugated cardboard, especially with fine corrugations.

That in the 1 illustrated porous paper or cardboard substrate 101 is compared to the adhesive application system 100 along a direction of displacement 103 relocated.

The porous paper or cardboard substrate 101 will be along the direction of displacement 103 through a not in 1 substrate displacement device shown, in particular a conveyor belt, displaced.

The adhesive application system 100 further comprises an adhesive applicator 105 , which is formed, the aqueous adhesive on the porous paper or cardboard substrate 101 to apply. The glue applicator 105 comprises in particular an adhesive application nozzle. The glue applicator 105 is also with an adhesive feed 104 for feeding glue from an in 1 not shown glue tank connected.

The adhesive application system 100 further comprises, in one embodiment, a plasma delivery device 106 which in relation to the direction of displacement 103 the porous paper or cardboard substrate 101 aligned behind the adhesive applicator 105 is arranged. The plasma delivery device 106 is formed plasma dem through the adhesive application device 105 onto the porous paper or cardboard substrate 101 applied adhesive feed to activate the adhesive.

The glue applicator 105 and the plasma delivery device 106 is in each case through a first or second control connection 108-1 , 108-2 Control technology with a control device 107 of the adhesive application system 100 connected, in which an adhesive application pattern is stored. The control device 107 is designed both the adhesive application device 105 for applying the adhesive application pattern to the porous paper or cardboard substrate 101 as well as the plasma delivery device 106 to activate the applied adhesive application pattern.

Depending on the porous paper or cardboard substrate used 101 The adhesive application pattern can comprise a combination of individual dots or lines which are located at certain positions on the surface of the porous paper or cardboard substrate 101 through the glue applicator 105 be applied.

The control device 107 is in particular with an operator station 109 of the adhesive application system 100 through a third control connection 108-3 connected in terms of control technology. An operator can, in particular, use the operator station to apply adhesive samples 109 enter which then the control device 107 to provide.

In particular, the control device 107 with a substrate detection device 110 , for example a light barrier or another suitable edge detector, through a fourth control connection 108-4 connected, which the spatial extent of the porous paper or cardboard substrate 101 detected and dependent on the displacement speed of the porous paper or cardboard substrate 101 along the direction of displacement 103 performs a route calculation in order to calculate the start and end of the adhesive application.

The porous paper or cardboard substrate provided with adhesive is then applied 101 folded and joined to obtain the folding boxes, for example.

Due to the high displacement speeds of the porous paper or cardboard substrates 101 high demands are placed on the adhesive time of the aqueous adhesive used. In particular, a bonding time of only 5 to 20 seconds must be achieved.

An aqueous adhesive according to the present disclosure comprises an aqueous phase in which polymers suitable for the formation of the adhesive layer are taken up as solid particles.

A correspondingly faster gluing process is achieved in that the porous paper or cardboard substrate 101 the aqueous phase of the aqueous adhesive quickly absorbs, so that the concentration of the solid particles increases and the polymers polymerize accordingly in a timely manner.

According to the present disclosure, preference is given to the use of so-called bio-adhesives, i.e. adhesives which are based on biological substances, such as starch, starch derivatives and / or other polysaccharides. Corresponding adhesives based on biological substances are preferred over traditional synthetic adhesives due to sustainability aspects, since advantages in terms of health compatibility, waste disposal and manufacturability can be achieved. This is due to the fact that bio-adhesives often have better health compatibility than synthetic adhesives and for this reason waste disposal is improved, and that corresponding bio-plastics can be produced from biological, in particular renewable, materials, in particular from renewable raw materials.

In particular, according to the invention, adhesives are preferred which are completely, that is to say 100%, based on biological substances.

However, the water content of corresponding aqueous adhesives based on biological substances is higher than the water content of conventional synthetic aqueous adhesives. As a result, the solids content of corresponding aqueous adhesives based on biological substances is lower than that of conventional synthetic aqueous adhesives. For example, the solids content in conventional synthetic aqueous adhesives is usually between 50% and 60%, whereas the solids content in corresponding aqueous adhesives based on biological substances according to the present invention is often only between 25% and 35%.

In the case of the corresponding aqueous adhesives based on biological substances according to the present disclosure, this means that the porous paper or cardboard substrate 101 has to absorb a larger amount of water and takes a longer time to do so, which would increase the gluing time.

In order to avoid a longer gluing time, the subject matter of the present disclosure comprises a pretreatment of the surface of the porous paper or cardboard substrate to be brought into contact with the aqueous adhesive 101 to determine the surface tension of the porous paper or cardboard substrate 101 to increase. By increasing the surface tension, the porous paper or cardboard substrate 101 absorb the water of the aqueous adhesive particularly quickly and an extension of the adhesive time when using aqueous adhesives based on biological substances can be prevented.

About the surface tension of the porous paper or cardboard substrate 101 To reduce prior to applying the adhesive, comprises the adhesive application system 100 another plasma delivery device 111 which in relation to the direction of displacement 103 the porous paper or cardboard substrate 101 aligned in front of the adhesive application device 105 is arranged, and is formed, plasma of the surface of the porous paper or cardboard substrate to be brought into contact with the adhesive 101 to feed.

Here, the further plasma supply device comprises 111 in particular an atmospheric pressure plasma nozzle which is designed to generate a plasma jet which is introduced into the ambient atmosphere at normal pressure and onto the surface of the porous paper or cardboard substrate to be treated 101 is judged. The further plasma delivery device 111 is with the control device 107 through a fifth control connection 108-5 connected in terms of control technology.

In particular, the adhesive application system 100 a holding device 113 on which the adhesive applicator 105 , the plasma delivery device 106 and in particular the further plasma delivery device 111 are attached together. By having the plasma delivery devices 106 , 111 on a common holding device 113 are attached, they no longer have to be aligned with one another after repositioning. In addition, the route relationships between the plasma supply devices remain 106 , 111 and the glue applicator 105 the same, so that no reprogramming of the route conditions in the control device 107 must be done when repositioning.

According to an in 1 Alternative embodiment not shown can be the adhesive application system 100 also just the plasma delivery device 106 and not the further plasma delivery device 111 have so that no pretreatment of the surface of the porous paper or cardboard substrate 101 through the further plasma supply device 111 he follows. This more cost-effective variant is useful when the penetration of the aqueous phase of the adhesive into the porous paper or cardboard substrate 101 occurs sufficiently quickly, but activation of the adhesive layer by the plasma delivery device 106 is nevertheless desired. This proves to be particularly helpful in the case of starch-containing adhesives, since the plasma activation also causes post-gelling or an increase in tack.

As from the 1 also shows, the adhesive application device 105 be a nozzle applicator, the nozzle opening of which is spaced from the surface of the porous paper or cardboard substrate by an air gap 101 is, ie the adhesive is applied to the porous paper or cardboard substrate via the air gap 101 applied. The glue applicator 105 but can alternatively also be used as an adhesive applicator 105 be formed, the nozzle mouth in contact with the porous paper or cardboard substrate 101 stands and thus ensures a contact order.

The glue applicator 105 can in particular be a multiple application head with several nozzle openings.

In particular, the control device controls 107 not only the glue application by means of the glue application device 105 but also activates the plasma delivery devices 106 , 111 based on the in the control device 107 deposited adhesive pattern. The route conditions and the current displacement speed of the porous paper or cardboard substrate can be taken into account 101 . The switching times of the adhesive application device can also be taken into account 105 , the so-called compensation time, and the time periods required for the activation of the plasma jet of the plasma supply devices 106 , 111 required are.

It is beneficial to the plasma delivery devices 106 , 111 only to be activated if necessary using the adhesive pattern, as this saves energy for activating the plasma jet and energy for generating the process fluid, such as compressed air. The control device is for this purpose 107 Via power lines with the respective plasma supply devices 106 , 111 connected, whereby the energy for the activation of the plasma jet is passed through this.

Alternatively, an in 1 Line (not shown) of at least one high voltage generator to the respective plasma supply devices 106 , 111 . The control device is activated via the line to the high-voltage generator 107 this based on the adhesive pattern or deactivates it.

The adhesive application system 100 also instructs a producer 115 for the process fluid of the respective plasma supply devices 106 , 111 on. The process fluid is typically compressed air, but it can also be another gas. The producer 115 can in a simple case be a gas cylinder or a compressor of a compressed air system. This is particularly advantageous if a compressor is only used for the adhesive application system 100 assigned. Small compressors have the advantage that they can build up pressure quickly and also control it.

The producer 115 is fluidic both through a first generator line 116-1 with the plasma delivery device 106 as well as through a second producer line 116-2 with the further plasma supply device 111 connected.

In principle, the producer can 115 by the control device 107 via the sixth control connection 108-6 can be controlled by activating or deactivating it. In one The simple case is an air switching valve that the fluid flow through the generator line 116-1 , 116-2 releases or blocks. This air switching valve can also be a proportional valve. A proportional valve has the advantage that over the control device 107 the amount of fluid can also be regulated.

By adapting the electrical supply voltage and / or the process fluid supply, the control device can 107 also adjust the treatment intensity to the production speed in order to achieve an even treatment success per unit area.

In particular, the plasma jet has a temperature of less than 100 ° C., in particular less than 60 ° C., in order to prevent burning or discoloration of the paper-based substrate 101 to avoid. Discoloration and burns are associated with an odor, which makes the use of such substrates 101 makes disadvantageous in food or cosmetic packaging.

2 shows a schematic representation of a method for applying an aqueous adhesive to a porous paper or cardboard substrate according to an embodiment.

The procedure 200 includes activation as an optional first step 201 a surface of the porous paper or cardboard substrate to be brought into contact with the adhesive 101 by supplying plasma to another plasma supply device 111 an adhesive application system 100 to the surface of the porous paper or cardboard substrate to be brought into contact with the adhesive 101 .

The procedure 200 includes application as a second step 202 of the aqueous adhesive on the porous paper or cardboard substrate 101 by an adhesive applicator 105 of the adhesive application system 100 .

The procedure 200 The third step involves relocating 203 the porous paper or cardboard substrate 101 along a direction of displacement 103 compared to the adhesive application system 100 .

The procedure 200 The fourth step is activation 204 des by the glue applicator 105 onto the porous paper or cardboard substrate 101 applied adhesive by supplying plasma through one with respect to the direction of displacement 103 aligned behind the adhesive applicator 105 arranged plasma delivery device 106 of the adhesive application system 100 to the applied adhesive.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102018108273 A1 [0003]
• DE 19532412 A1 [0004]

Claims (10)

Adhesive application system (100) for applying an aqueous adhesive to a paper or cardboard substrate (101), the paper or cardboard substrate (101) being displaceable relative to the adhesive application system (100) along a displacement direction (103), comprising: - an adhesive application device (105) which is designed to apply the aqueous adhesive to the paper or cardboard substrate (101), - At least one plasma supply device (106, 111) and - A control device (107) in which at least one adhesive application pattern is stored and which is designed, both the adhesive application device (105) for applying the at least one adhesive application pattern and the at least one plasma supply device (106, 111) for activating the aqueous adhesive and / or to activate the paper or cardboard substrate (101). Adhesive application system (100) according to Claim 1 , wherein the at least one plasma supply device (106) is arranged in alignment behind the adhesive application device (105) with respect to the displacement direction (103) of the paper or cardboard substrate (101) and is formed, controlled by the control device (107), the adhesive to activate. Adhesive application system (100) according to any one of the preceding claims, wherein the at least one plasma feed device (111) is arranged and designed in alignment with the displacement direction (103) of the paper or cardboard substrate (101) in front of the adhesive application device (105) by the control device (107), to supply plasma to the surface of the paper or cardboard substrate (101) to be brought into contact with the aqueous adhesive in order to allow the paper or cardboard substrate (101) to take up the aqueous phase of the aqueous adhesive. to accelerate. Adhesive application system (100) according to one of the preceding claims, wherein the adhesive application system (100) has a holding device (113) on which the adhesive application device (105) and the at least one plasma feed device (106, 111) or the plasma feed devices (106, 111) together, in particular are attached at a fixed distance from one another. Adhesive application system (100) according to one of the preceding claims, wherein the adhesive application system (100) has a substrate detection device (110), in particular a light barrier, which is designed to detect a spatial extent or a leading edge of the paper or cardboard substrate (101) , wherein the control device (107) is connected and designed in terms of control technology with the substrate detection device (110), the adhesive application device (105) and with one or both plasma supply devices (106, 111), the adhesive application device (105) and the one or both plasma supply devices (106 , 111) as a function of the detected spatial extent or a dimension of the paper or cardboard substrate (101) stored in the control device (107). Adhesive application system (100) according to one of the preceding claims, wherein the aqueous adhesive is an aqueous adhesive based on biological substances, and wherein the biological substances include in particular starch, starch derivatives and / or further polysaccharides. Method (200) for applying an aqueous adhesive to a paper or cardboard substrate (101) with an adhesive application system (100), the method (200) having the following method steps: - Application (202) of the aqueous adhesive to a paper or cardboard substrate (101) by an adhesive application device (105) of the adhesive application system (100), - Displacement (203) of the paper or cardboard substrate (101) along a displacement direction (103) with respect to the adhesive application system (100) and - Activation (204) of the adhesive applied by the adhesive application device (105) to the paper or cardboard substrate (101) by the supply of plasma by a plasma supply device arranged in alignment with the displacement direction (103) behind the adhesive application device (105) ( 106) of the adhesive application system (100) to the applied adhesive. Method (200) according to Claim 6 , the method (200) having the following method step, which is carried out before the application (202) of the aqueous adhesive to a paper or cardboard substrate (101): - activating (201) the surface to be brought into contact with the adhesive of the paper or cardboard substrate (101) by supplying plasma from a further plasma supply device (111) of the adhesive application system (100) to the surface of the paper or cardboard substrate (101) to be brought into contact with the adhesive, the further Plasma supply device (111) is arranged in alignment with the direction of displacement (103) of the paper or cardboard substrate (101) in front of the adhesive application device (105). Method (200) according to Claim 7 or 8th wherein the application (202) of the aqueous adhesive to the paper or cardboard substrate (101), the activation (204) of the applied adhesive, and in particular the activation (201) of the surface of the paper to be brought into contact with the adhesive or the cardboard substrate (101) is carried out by a single control device (107) based on at least one adhesive application pattern stored in the control device (107) of the adhesive application system (100). Method (200) according to one of the Claims 7 until 9 , wherein - a spatial extent or leading edge of the paper or cardboard substrate (101) is detected by a substrate detection device (110), in particular by a light barrier, and - the adhesive application device (105) and one or both plasma supply devices (106, 111) is controlled by the control device (107) as a function of the detected spatial extent or a leading edge of the paper or cardboard substrate (101).

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