EP3127670B1 - Method for impregnating material panels - Google Patents

Description

The invention relates to a method for impregnating material boards, in particular wood fiber boards, material boards produced by this method and a plant for carrying out the method.

When manufacturing MDF (medium density fiberboard) or HDF (high density fiberboard), it is often desired that the end product has certain properties that are relevant for further production steps and/or use. One such property can be conductivity, for example, which plays a role for a fiberboard either when the board itself is powder coated, or is desired if the board is to be used as a carrier board for laminate floor panels and the floor must have antistatic properties. Conductivity can be achieved by adding salts during the manufacturing process, for example in the refining process. Another desired property can be a fire-retardant design. Because relatively high temperatures act on the mixture of pre-treated wood fibers when the wood fibers are dried in the blowline, unfortunately interactions between the added salts and other components such as glue often occur.

Another disadvantage is that all wood fibres are treated, whether this is necessary or not. To compensate for this disadvantage, DE 199 63 203 A1 proposed that, in order to manufacture laminate flooring panels, a carrier plate is first produced from lignocellulose-containing wood material, which is impregnated at least in some areas with an impregnating agent, whereby the impregnating agent penetrates into the carrier plate or soaks it. The carrier plate is then usually coated with melamine resin-impregnated paper in a short-cycle press, divided into the impregnated areas and then provided with a profile for installation that enables glue-free installation. The impregnation of the edge areas is intended to provide laminate flooring panels that are more resistant to moisture and wetness.

The production of such carrier boards using the above-mentioned method is very time-consuming, as the absorption of the impregnation medium into the board takes a certain amount of time. In addition, to ensure even impregnation, the top of the carrier board must be evenly wetted with the impregnation medium. Density fluctuations within the carrier board lead to an uneven distribution of the impregnation, which is not visible from the outside, so there is a risk that panels later made from the carrier board will not be sufficiently impregnated, particularly in the edge area where moisture can penetrate the laid floor.

In the following, the terms "vacuum" and "negative pressure" are used synonymously. This means that a suitable negative pressure is generated and applied, the value of which is lower than the prevailing atmospheric pressure and/or the positive pressure also used according to some aspects of the invention.

From the EP 2 241 426 A1 A process for producing generic MDF or HDF boards is known, which is intended to solve the problems mentioned above. Cakes of wood fibers or wood chips moistened with an adhesive are spread on a continuously rotating conveyor belt and exposed to a vacuum behind the pre-press and before the hot press, and at the same time an impregnation medium applied to the cake, which is distributed throughout the cake due to the vacuum. A similar process is also used in the EN 10 2008 049 132 A1 described.

However, these methods have the disadvantage that the application unit has a large number of nozzles, the number of which is determined by the type of impregnation required. If the impregnation pattern is to be changed, it is necessary to readjust all the nozzles in order to be able to reproduce the desired pattern on the plate. These methods are very cumbersome and costly, as many nozzles are required distributed over the entire surface of the plate.

• Verwendung von Holzwerkstoffen mit erhöhter Feuchte- bzw. Wasserbeständigkeit.

As already described, problems often arise when products that have wood-based materials as a carrier material are used in areas with increased air humidity or direct exposure to moisture due to material swelling. This swelling can lead to a variety of graded damage patterns, ranging from slight swelling that does not significantly limit the usefulness of the product to complete destruction of the material that requires replacement. The application in which the product is used is often decisive. While applications in the private sector as wall and ceiling cladding usually prove to be uncritical, uses as flooring in the private or public sector are to be classified as more critical. Use in public areas, for example as partition walls, shower cladding, etc. is also very prone to complaints. In order to take this increased risk into account in critical applications, different strategies are used:

• Use of wood materials with increased moisture or water resistance.

For this purpose, the wood materials are manufactured with glues that lead to reduced swelling. These include phenol glues, isocyanate glues and MUPF glues (melamine-urea-phenol-formaldehyde glues). However, these only reduce swelling. This means that with repeated wetting and drying, an ever greater residual swelling will remain, which will ultimately lead to a complaint.

• Verbesserte Versiegelung der von Feuchte- bzw. Wassereinwirkung betroffenen Bereiche.

In addition, the entire wood material has to be manufactured with the glue, although the swelling is usually only a problem with the edge. The disadvantage of this technology is that the glues are more expensive than the urea-formaldehyde glues commonly used and that they slow down the manufacturing processes of the wood materials, thus making them more expensive.

• Improved sealing of areas affected by moisture or water.

• Verwendung von höherwertigen Werkstoffen.

This is also a common procedure for reducing the risk in use. This is usually achieved by using higher quality adhesives to fix edges, etc. However, it is clear that this does not permanently prevent damage, particularly in the commercial and public sector, due to the intensive use of aggressive cleaning and disinfection agents. This strategy is not an option for floors (laminate floors) anyway.

• Use of higher quality materials.

In interior design, it is of course possible to use higher-quality materials such as compact panels. However, these materials are at least five to ten times more expensive than standard wood materials.

One alternative is the targeted impregnation of the HWS board with substances that can reduce swelling to almost zero and that leave no residual swelling after the material has dried again. So-called prepolymers based on low-molecular isocyanates can be used for this process. The impregnating material is usually pressed into the material in a press and this impregnation process is supported by a negative pressure applied from the underside of the board. Excess prepolymer is collected in collecting channels on the underside and fed back into the process. The impregnating agent is usually only applied to the areas where there will later be cut edges or profiles. The desired quality level can be determined by selecting the width of the impregnation yourself.

• Die Presse ist aufwendig, da eine sehr große Anzahl von Düsen und Saugstellen erforderlich ist und der Durchfluss an jeder einzelnen Düse nur schwer zu kontrollieren ist. Es ist daher schwierig, eine gleichmäßige Durchimprägnierung sicherzustellen.
• Insbesondere bei inhomogenen Werkstoffen (und das ist bei den meisten Werkstoffen der Fall) ist das Beschicken mehrerer Düsen gleichzeitig von Nachteil, da an den poröseren Stellen automatisch mehr Bindemittel durchgepresst/gesaugt wird.
• Es kann nur punktförmig imprägniert werden, das heißt, das Imprägnieren einer Linie erfolgt mittels einer Vielzahl von Punkten, von denen aus das Imprägniermittel (oder Bindemittel) sich kreisförmig ausbreitet. Die Linie wird durch eine Aneinanderreihung sich überlappender Kreise gebildet und dadurch wird der Imprägniermittelverbrauch stark erhöht.
• Es kann nur im Taktverfahren gearbeitet werden.
• Beschickung und Entleerung der Presse sind aufwendig und zeitraubend.
• Das Imprägnieren unterschiedlicher Formate ist schwierig, da die Pressplatten gefräst sind und die Kanäle in den Pressplatten auf der Druck- und der Vakuumseite dem Format entsprechen müssen. Neue Formate bedingen neue Pressplatten (Plattenwechsel, Platten sind extrem teuer).
• Bei großen Formaten sind extrem große Pressen und Pressplatten erforderlich - die Anlagen werden unverhältnismäßig teuer.
• Die Reinigung der Anlage stellt ein großes Problem dar. Insbesondere bei der Imprägnierung mittels Bindemitteln, welche mit Feuchtigkeit reagieren und noch dazu stark gesundheitsschädlich sind, ist die Aufgabe beinahe unlösbar.

This procedure is not optimal for a variety of reasons:

• The press is complex because it requires a very large number of nozzles and suction points and the flow at each individual nozzle is difficult to control. It is therefore difficult to ensure uniform impregnation.
• Especially with inhomogeneous materials (and this is the case with most materials), feeding several nozzles at the same time is disadvantageous, since more binding agent is automatically pressed/sucked through the more porous areas.
• Impregnation can only be carried out point-wise, i.e. the impregnation of a line is carried out by means of a large number of points from which the impregnating agent (or binder) spreads out in a circle. The line is formed by a series of overlapping circles and this greatly increases the consumption of impregnating agent.
• Work can only be carried out in a cyclical manner.
• Loading and emptying the press is complex and time-consuming.
• Impregnating different formats is difficult because the press plates are milled and the channels in the press plates on the pressure and vacuum sides must match the format. New formats require new press plates (changing plates, plates are extremely expensive).
• Large formats require extremely large presses and press plates - the systems become disproportionately expensive.
• Cleaning the system is a major problem. The task is almost impossible, especially when impregnating using binding agents that react with moisture and are also extremely harmful to health.

In the WO 2006/100275 A1 discloses a finishing composition for application by continuous ink jet technology to a textile substrate. The composition comprises a dispersion or emulsion of a functional finishing agent in a carrier, and the applied composition has a conductivity of more than 500 pS/cm. The particle size in the dispersion or emulsion of the composition is less than about 5 micrometers. By ensuring sufficient fineness of the particles, effective and reliable droplet deposition can be achieved without clogging the nozzles.

The object of the present invention is therefore to provide a method which overcomes the disadvantages of the prior art.

The invention is therefore based on the technical task of finding a technology that eliminates the problems described above or achieves significant simplifications with regard to the process.

The object is achieved by a method having the features of claim 9. Advantageous developments of the method according to the invention are described in the dependent subclaims.

The invention therefore relates to a method according to claim 9 for impregnating material boards, in particular wood fibre boards.

In the sense of the disclosure, the term "endless strand of material plates" is understood to mean a continuous sequence of material plates that are arranged one behind the other on the transport device and thereby form a strand (or continuous stream) of individual plates during the impregnation process, which is continuously renewed during the impregnation process (i.e. during the movement of the transport device) by the supply of new material plates that are still to be impregnated at one end (the "beginning") of the transport device and by the corresponding removal of the already impregnated material plates at the other end (the "end") of the transport device, and is thus "endless" during the impregnation process.

According to the invention, a method for impregnating material boards, in particular wood fibre boards, is provided, in which individual material boards are placed on a transport device in such a way that the material boards abut one another with their edges and rest on the transport device as an endless strand of material boards, the endless strand of material boards is continuously guided through an impregnation station for introducing an impregnation medium into the material boards, wherein the impregnation medium is applied by means of a plurality of application devices which are arranged in a row over the full width the material plate and are individually controllable, is applied in a time-controlled manner during the continued transport of the endless strand of material plates.

A preferred method is one in which the impregnation medium is introduced into the depth of the material plate by means of a negative pressure or vacuum which acts on the material plate from the underside of the transport device through openings in the transport device.

A method is also preferred in which the individual application devices of the plurality of application devices are controlled in a time-controlled manner such that each individual application device dispenses impregnation medium only at a preselected time.

According to the invention, a method is preferred in which the timing of the application devices is synchronized with the speed of the transport of the individual material plates of the strand or of the continuous material plate strand, wherein the transport of the individual material plates of the strand or of the continuous material plate strand takes place by means of the transport device.

Also preferred is a method in which the timing of the application devices and/or the synchronization of the transport device is controlled and/or regulated by means of a processor.

Particularly preferred is a method in which the impregnation medium is applied by means of a plurality of application devices in the form of nozzles.

According to the invention, a method in which the impregnation medium is applied by means of a plurality of application devices in the form of application heads, wherein the application heads press the impregnation medium into the depth of the material plates by applying excess pressure.

A method is particularly preferred in which the spatial distribution of the impregnation medium in the depth of the material plate is controlled by appropriately specifying the overpressure in the application device and/or the negative pressure acting on the material plate from the other side.

The invention also relates to a process in which the impregnation medium is used in liquid, dissolved or suspended form or as an emulsion.

According to the invention, a method is preferred in which the impregnation medium changes the water absorption and/or the swelling and/or the strength values and/or the flammability of the material plate.

Particularly preferred is a method according to the invention in which the material panels are formed from or contain wood materials, mineral-bonded wood materials or mineral materials or a combination of these materials.

The task is solved by using a continuous process. First, a stack of plates is formed into an endless strand. The material plates can be arranged on the transport device in such a way that adjacent plates meet with their (opposite) edges (i.e. touch each other at these edges) or, alternatively, that the plates are separated from each other by a distance on the transport device (i.e. do not touch). It is also conceivable that the panels are arranged on the transport device in such a way that some of the panels abut each other at their edges (i.e. touch) and other panels do not touch at their edges. The strand formed in this way runs under an impregnation station at an accelerated rate through driven rollers. The panels are additionally fixed in place in this area by mangle rollers. In this area, an impregnating agent is pressed into the panels under pressure via movable beams. This process is supported by counter beams on the back of the panels, which are subject to a negative pressure. These are also movable and are positioned under the pressure beams. The application nozzles can be controlled individually and, if necessary, also operated differently depending on the application quantity.

Alternatively, a material plate strand can also be used in the method according to the invention. Such a material plate strand can, for example, be formed beforehand from corresponding wood fibers and be in the form of a cake, which is then further processed into a corresponding material plate after impregnation.

It is particularly advantageous if the cake is pressed or at least pre-pressed before impregnation

This process creates strip-shaped impregnations on the panels. For elements where a transverse side is also to be impregnated, the panels are either run through the system a second time or are impregnated in a second station after an angle transfer.

An advantage of the method according to the invention is that the impregnation medium can be introduced into the material plate in any desired pattern. This makes it possible to provide each plate with a different pattern if necessary. If, for example, floorboards are to be formed from the plate, this can be done by appropriately controlling the large number of application devices for the impregnation medium. If the following plate is then intended for square panels, the impregnation can be done by changing the control of the large number of application devices for the impregnation medium. This enables the impregnation to be introduced economically and effectively.

The method according to the invention can be used on a large number of board types. The suitability for the use of certain board types is essentially influenced by the density and porosity of the material. The impregnation method according to the invention is controlled by the application of pressure and vacuum. Therefore, in addition to wood-based panels such as wood fiber boards, other mineral-bonded wood materials (HWS) (cement-bonded chipboard) and mineral board materials (fiber cement) are also suitable and preferred for the method according to the invention. The person skilled in the art is able to check the suitability of a particular material board for the method according to the invention by means of simple tests.

Also disclosed is an impregnated material plate produced by the process according to the invention.

• einzelne Werkstoffplatten oder einen kontinuierlichen Werkstoffplattenstrang auf eine Transportvorrichtung derart aufgibt,
• dass die einzelnen Werkstoffplatten hintereinander angeordnet als endloser Strang von Werkstoffplatten auf der Transportvorrichtung aufliegen oder der kontinuierliche Werkstoffplattenstrang auf der Transportvorrichtung aufliegt,
• dass der Strang von einzelnen Werkstoffplatten oder der kontinuierliche Werkstoffplattenstrang kontinuierlich durch eine Imprägnierstation zum Einbringen eines Imprägniermediums in die Werkstoffplatten oder den Werkstoffplattenstrang geführt wird,
• wobei das Imprägniermedium mittels einer Vielzahl von Auftragsvorrichtungen, welche mindestens in einer Reihe über die volle Breite der einzelnen Werkstoffplatte oder des kontinuierlichen Werkstoffplattenstrangs angeordnet und individuell ansteuerbar sind, zeitgesteuert während des fortgesetzten Transportierens der einzelnen Werkstoffplatten des Strangs oder des kontinuierlichen Werkstoffplattenstrangs aufgetragen wird.

Described herein are impregnated material boards, in particular wood fibre boards, obtainable by a process in which

• individual material plates or a continuous Material plate strand is placed on a transport device in such a way that
• that the individual material plates are arranged one behind the other as an endless strand of material plates on the transport device or the continuous strand of material plates is resting on the transport device,
• that the strand of individual material plates or the continuous material plate strand is continuously guided through an impregnation station for introducing an impregnation medium into the material plates or the material plate strand,
• wherein the impregnation medium is applied in a time-controlled manner during the continued transport of the individual material plates of the strand or the continuous material plate strand by means of a plurality of application devices which are arranged at least in one row over the full width of the individual material plate or the continuous material plate strand and can be individually controlled.

Also described is an impregnated material plate, wherein the impregnation medium is introduced into the depth of the material plate by means of a negative pressure which acts on the material plate from the underside of the transport device through openings in the transport device.

Also described is an impregnated material plate, wherein the individual application devices of the plurality of application devices are controlled in a time-controlled manner such that each individual application device releases impregnation medium only at a preselected time.

An impregnated material plate is also described, whereby the time control of the application devices can be the speed of the transport of the arranged synchronized, whereby the transport of the individual material plates of the strand or the continuous material plate strand is carried out by means of the transport device.

Also described is an impregnated material plate, wherein the timing of the application devices and/or the synchronization of the transport device is controlled and/or regulated by means of a processor.

Also described is an impregnated material plate, wherein the impregnation medium is applied by means of a plurality of application devices in the form of nozzles.

Also described is an impregnated material plate, wherein the impregnation medium is applied by means of a plurality of application devices in the form of application heads, wherein the application heads press the impregnation medium into the depth of the material plates by applying excess pressure.

Also described is an impregnated material plate, wherein the spatial distribution of the impregnation medium in the depth of the material plate is controlled by specifying the overpressure in the application device and/or the negative pressure acting on the material plate from the other side.

Also described is an impregnated material plate, wherein the impregnation medium is used in liquid, dissolved or suspended form or as an emulsion.

What is described is an impregnated material plate, wherein the impregnation medium changes the water absorption and/or the swelling and/or the strength values and/or the flammability of the material plate.

What is described is an impregnated material board, whereby the material board is made of or contains wood materials, mineral-bonded wood materials or mineral materials or a combination of these materials.

The object of the invention is also achieved by a system which has the features of claim 1. Advantageous further developments of the system according to the invention are described in the dependent subclaims.

Another object of the present invention is a plant for carrying out the method according to the invention.

The subject matter of the invention is therefore a system according to claim 1.

A system is preferred in which the impregnation station further comprises a vacuum station which is arranged below the transport device and has a plurality of suction devices, so that for each application device arranged above the transport device there is a suction device arranged below the transport device and each individual suction device has at least one control element which can be controlled individually.

A system is disclosed in which the application devices are designed as nozzles.

According to the invention, a system in which the application devices are designed as application heads.

A system is also preferred in which the application heads rest with their side borders on the surface of the material plate to be impregnated and are optionally provided with seals. It is particularly preferred that the application heads are arranged in two parallel rows across the full width of the transport device. It is extremely preferred that the distance between the two rows is variable.

According to the invention, a system is also preferred, wherein a processor is further provided for controlling the control elements of the application devices and/or for controlling the suction devices and/or for controlling the transport device.

• kontinuierliches und kontrolliertes Aufbringen des Imprägniermittels/Bindemittels mit der Möglichkeit, jede Düse einzeln anzusteuern
• kontinuierlicher durchlaufender Plattenstrang mit hohem Vorschub
• eine geringe Zahl an Druck- und Saugdüsen
• hohe Anlagenleistung
• präzise Dosierung und daher niedriger Imprägniermittel-/Bindemittelverbrauch
• große Flexibilität, da keine Breitenverstellung erforderlich und variable Länge durch Endlosfahrweise
• leichte Reinigung durch geringe Anzahl an Düsen auf Druck- und Vakuumseite und Entfallen der Abflusskanäle und Pressplatten
• wesentlich niedrigere Anlagekosten
• wesentlich niedrigerer Energieverbrauch beim Betreiben der Anlage
• keine aufwendigen Sicherheitsvorkehrungen
• Einbau in bestehende Anlagen und Onlinebetrieb möglich
• große Formate können ohne Mehraufwand imprägniert werden

Such a system offers the following advantages over the state of the art (stationary system):

• Continuous and controlled application of the impregnating agent/binder with the possibility of controlling each nozzle individually
• continuous plate string with high feed
• a small number of pressure and suction nozzles
• high system performance
• precise dosing and therefore low impregnating agent/binder consumption
• great flexibility, as no width adjustment is required and variable length due to continuous operation
• Easy cleaning due to small number of nozzles on pressure and vacuum side and elimination of drainage channels and press plates
• significantly lower investment costs
• significantly lower energy consumption when operating the system
• no complex security precautions
• Installation in existing systems and online operation possible
• Large formats can be impregnated without additional effort

• Verfahren zum Imprägnieren von Werkstoffplatten 1, insbesondere Holzfaserplatten, bei dem man
• einzelne Werkstoffplatten 1, die zuvor gepresst wurden, oder einen kontinuierlichen Werkstoffplattenstrang, bestehend aus zuvor gepressten Kuchen, auf eine Transportvorrichtung 11 derart aufgibt,
• dass die einzelnen Werkstoffplatten 1 hintereinander angeordnet als endloser Strang von Werkstoffplatten auf der Transportvorrichtung 11 aufliegen oder der kontinuierliche Werkstoffplattenstrang auf der Transportvorrichtung 11 aufliegt,
• dass der Strang von einzelnen Werkstoffplatten 1 oder der kontinuierliche Werkstoffplattenstrang kontinuierlich durch eine Imprägnierstation 12 zum Einbringen eines Imprägniermediums in die Werkstoffplatten 1 oder den Werkstoffplattenstrang geführt wird,
• wobei das Imprägniermedium mittels einer Vielzahl von Auftragsvorrichtungen 13, in Form von Düsen 18 und/oder Auftragsköpfen 14, welche mindestens in einer Reihe über die volle Breite der einzelnen Werkstoffplatte 1 oder des kontinuierlichen Werkstoffplattenstrangs angeordnet und individuell, wobei aus der Vielzahl von Auftragsvorrichtungen 13einzelne Auftragsvorrichtungen 13 auswählbar sind, ansteuerbar und/oder in der Auftragsmenge unterschiedlich bedienbar sind, zeitgesteuert während des fortgesetzten Transportierens der einzelnen Werkstoffplatten 1 des Strangs oder des kontinuierlichen Werkstoffplattenstrangs aufgetragen wird.

The claimed system operates according to the following process:

• Method for impregnating material boards 1, in particular wood fibre boards, in which
• individual material plates 1, which have been previously pressed, or a continuous material plate strand, consisting of previously pressed cakes, are placed on a transport device 11 in such a way that
• that the individual material plates 1 are arranged one behind the other as an endless strand of material plates on the transport device 11 or the continuous material plate strand rests on the transport device 11,
• that the strand of individual material plates 1 or the continuous material plate strand is continuously guided through an impregnation station 12 for introducing an impregnation medium into the material plates 1 or the material plate strand,
• wherein the impregnation medium is applied by means of a plurality of application devices 13, in the form of nozzles 18 and/or application heads 14, which are arranged at least in one row over the full width of the individual material plate 1 or the continuous material plate strand and individually, whereby from the plurality of application devices 13 individual application devices 13 can be selected, controlled and/or operated differently in terms of the application quantity, is applied in a time-controlled manner during the continued transport of the individual material plates 1 of the strand or the continuous material plate strand.

The method is further characterized in that the impregnation medium is introduced into the depth of the material plate 1 by means of a negative pressure which acts on the material plate 1 from the underside of the transport device 11 through openings in the transport device 11.

The method is further characterized in that the individual application devices 13 of the plurality of application devices 13 are controlled in a time-controlled manner such that each individual application device 13 dispenses impregnation medium only at a preselected time and/or the time control of the application devices 13 is synchronized with the speed of the transport of the individual material plates 1 of the strand or of the continuous material plate strand, wherein the transport of the endless strand of material plates 1 takes place by means of the transport device 11.

The method is further characterized in that the timing of the application devices 13 and/or the synchronization of the transport device 11 is controlled and/or regulated by means of a processor.

The method is further characterized in that the application heads 14 press the impregnation medium into the depth of the material plates 1 by applying excess pressure.

The method is further characterized in that the spatial distribution of the impregnation medium in the depth of the material plate 1 is controlled by appropriately specifying the overpressure in the application device 13 and/or the negative pressure acting on the material plate 1 from the other side.

The process is further characterized by the use of the impregnation medium in liquid, dissolved or suspended form or as an emulsion.

The method is further characterized in that the impregnation medium changes the water absorption and/or the swelling and/or the strength values and/or the flammability of the material plate 1 and/or that the material plates 1 are formed from or contain wood materials, mineral-bonded wood materials or mineral materials or a combination of these materials.

Furthermore, immediately before impregnation, a mixture of components can be used which, through reaction with one another or through complementary effects, achieve a further improvement in water resistance, an additional product property or product improvement. Impregnation with various substances is also possible. Of course, carrier materials that are not made of wood materials can also be impregnated. Partial impregnation in the surface and/or on the back is also possible.

• Figur 1 in drei Teilansichten imprägnierte Werkstoffplatten;
• Figur 2 eine Draufsicht auf die Imprägnieranlage;
• Figur 3 einen Schnitt durch die Imprägnierstation entlang der Linie A-A der Figur 2; und
• Figur 4 einen Schnitt durch eine Ausführungsform eines Auftragskopfes entlang der Linie B-B der Figur 2.

The invention is described in more detail with reference to the accompanying drawings. It shows:

• Figure 1 impregnated material panels in three partial views;
• Figure 2 a top view of the impregnation plant;
• Figure 3 a section through the impregnation station along line AA of the Figure 2 ; and
• Figure 4 a section through an embodiment of an application head along the line BB of the Figure 2 .

The following description explains the invention using various embodiments. The described embodiments are not intended to limit the scope of the present invention to these. Rather, these embodiments only show the wide applicability of the invention. Further embodiments and application examples will be obvious to the person skilled in the art from the above-mentioned embodiments and the description of the invention, the scope of protection being defined by the appended claims.

The Figure 1 with the partial figures 1a, 1b and 1c shows different impregnated material plates 1 produced by the method according to the invention. The Figures 1a and 1b each show a material plate 1 with impregnated areas 2 and non-impregnated areas 3. In the Figures 1a and 1b It can be seen that the impregnated areas 2 can be geometrically very different. An impregnation pattern according to the Figure 1 is suitable for later cutting the material board, which is then a wood fibre board, into planks, which are then provided with tongue and groove to enable glue-free assembly. In the Figure 1a The impregnated wood fibre board is then suitable for cutting into small panel elements. The respective impregnation patterns can be produced using the method according to the invention.

The impregnation pattern can be applied in one operation, whereby the impregnations can be formed both along the running direction of the plates and across the running direction in one pass through the impregnation station. This means that by specifically controlling, for example, only the outer application devices of the large number of application devices, impregnation is achieved in the running direction of the transport device and only at the edge of the material plates. If, for example, only one of the application devices is controlled one after the other in such a way that the application device to the right is always addressed, an impregnation is created that extends diagonally across the material plate.

The invention also provides that almost any pattern can be created by appropriate, targeted control. Such patterns can be rectangles, squares, diamonds, trapezoids or even circles. These patterns can be obtained in a simple manner by targeted and individual control of the individual application devices.

However, the invention also provides for initially applying only the impregnations required transversely to the running direction of the plate and then, in a second step, after turning the plate by 90°, applying the remaining impregnations, whereby no further impregnation is applied to the places where the impregnation is already present. This then leads to a saving of impregnation material.

The Figure 1c shows a material plate 1 with impregnated areas 2 and non-impregnated areas 3. The impregnated areas 2 are each arranged around a saw cut 4 that is to be made later. The saw cut 4 results in this material being removed later. It is therefore not necessary to first treat this later saw cut 4 with impregnating material in order to then remove this area again. According to the invention, this impregnation pattern can be applied to the material plates by means of an application device arranged in two parallel rows.

Figure 2 shows an impregnation system 10 for carrying out the method according to the invention. The individual material plates 1 are placed on a transport device 11. The individual plates 1 lie against one another so that an endless strand of material plates 1 is formed. This endless strand is then moved in the transport direction R and passes through the impregnation station 12. A large number of application devices 13 (not shown) are arranged inside the impregnation station 12. A vacuum station 19 (not shown) can also be arranged below the transport device 11, which consists of a large number of suction devices 15 (not shown). In addition to the components mentioned, the impregnation system can also comprise further stations in which the material plates are processed. In particular, a drying station can be provided.

However, systems are also conceivable that first form a cake directly from the corresponding wood fibers, which is then impregnated and then pressed under pressure and/or temperature to form a material plate.

It is particularly advantageous if the cake is pressed or at least pre-pressed before impregnation.

It is thus possible to integrate the desired impregnation into the manufacturing process of the material panels by providing an impregnation station according to the invention in the system.

The Figure 3 now shows a section through an impregnation station 12 along the section line AA of the Figure 2 . The material plate 1 rests on the transport device 11 and is guided by this through the impregnation station 12. A plurality of application devices 13 are arranged above the material plate 1. These application devices 13 advantageously each have a seal 17 which closes the application device 13 off from the top of the material plate 1. This seal 17 is provided with a contact pressure which is sufficient to achieve the sealing effect, but is selected such that transport of the plate 1 is still possible. Each application device is also provided with a control element 16. This control element regulates the inflow and, if necessary, also the pressure of the impregnation medium to be applied. It is clear that the application devices 13 are connected to a corresponding storage and/or conveyor system for the impregnation media.

A vacuum station 19 is arranged beneath the transport device. The vacuum station 19 comprises a plurality of suction devices 15. For this purpose, the transport device is designed accordingly so that it is designed to pass through pressure differences. However, it is also possible to interrupt the transport device 11 in the area of the impregnation station in such a way that the suction devices 15 are in direct contact with the underside of the material plate. At the contact points Seals 17 are advantageously provided for connecting the suction devices 15 to the plate 1. The individual suction devices 15 also have control elements 16 which regulate the vacuum to be applied.

The control devices 16 of the application devices 13 and the suction devices 15 are each designed to be controllable and adjustable independently of one another and independently of one another. This makes it possible to individually design the application of the impregnation medium onto and the introduction into the material plate 1 and to form any desired pattern on the surface and in the depth of the material plate 1.

A processor (not shown) is advantageously provided for controlling and regulating the control devices 16. This processor is part of a computer-controlled measuring and control device.

Depending on the application area, the application device 13 can be designed in different ways. Nozzles can be used, in which case the seal 17 may not be necessary. The application device can also be designed as an application head 14. These application heads can have different geometric shapes. They can be rectangular, square or circular. This shape is determined by the chemical, physical and rheological properties of the impregnation medium. The expert is able to choose the shape accordingly.

In the Figure 4 An application head specially designed according to the invention is now shown. The Figure 4 represents the interior of the impregnation station 12 along the cutting line BB of the Figure 2 The application head is divided and the sub-application heads have a defined distance to each other. The division of the application heads 14 can be achieved by providing two rows of application heads 14 arranged parallel to each other. In the Figure 4 the indicated profiles of the material plate in the shape of floors are shown together with the separating cut that is made by a saw. When sawing and profile milling, part of the impregnated area is usually milled away. If the area were impregnated with an undivided application head, all of the material in these areas would be lost. Using the split head reduces the loss of impregnating material. In addition, the impregnation takes place on the back of the final product, because this also saves on the impregnating agent. By variable control of the pressure and the application quantity, the geometry of impregnations can also be controlled. With a lot of pressure and application quantity, linear impregnation patterns are created ( Figure 4 , left part), with little pressure and reduced application quantity, funnel-shaped application images are created ( Figure 4 , right part). This means that considerable savings can be made on the relatively expensive impregnation materials. In the case of full impregnation, part of the impregnation material would be removed again when sawing or cutting.

The split application head also allows multiple impregnations and impregnations with multi-component materials. This means that multiple or multi-component impregnations can be carried out in one operation, for example isocyanates + polyols, paraffin + paint, etc. Furthermore, different impregnation materials can be used on both sides of the profile.

Reference list

1

Material plate

2

impregnated area

3

non-impregnated area

4

Saw cut

5

Plate top

6

Plate underside

7

Spring side

8th

Groove side

10

Impregnation plant

11

Transport device

12

Impregnation station

13

Application device

14

Application head

15

Suction device

16

Control

17

poetry

18

jet

19

Vacuum station

R

Transport direction

A-A

Cutting line

B-B

Cutting line

Claims (15)

1. Plant for manufacturing an impregnated material board, with a transport device (11) and an impregnating station (12) arranged above the transport device (11), wherein the impregnation station (12) is provided with a plurality of applicator devices (13), formed as applicator heads (14), which are arranged in a row over the full width of the transport device (11) and each individual applicator device (13) has at least one control element (16) that can be actuated individually,
   wherein
   the control element (16) controls the feed flow and, if necessary, the pressure of the impregnating medium to be applied, and the applicator heads (14) are formed to lie with their side limiters on the surface of the material board to be impregnated (1) and, if necessary, the applicator heads are provided with seals (17).
2. Plant according to claim 1, characterized in that the impregnation station (12) further contains a vacuum station (19), which is arranged underneath the transport device (11) and has a plurality of suction devices (15) so that there is one suction device (15) arranged underneath the transport device (11) for each applicator device (13) arranged above the transport device (11), and each individual suction device (15) has at least one control element (16) which is individually actuatable.
3. Plant according to at least one of the claims 1 to 2, characterized in that the control elements (16) of the applicator devices (13) and of the suction devices (15) are designed to be actuatable and controllable independently of each other and independently among each other in order to individually design the application of the impregnating medium to and the introduction into the material board 1 to form any pattern at the surface and in the depth of the material board 1.
4. Plant according to at least one of the claims 1 to 3, characterized in that almost any pattern of the impregnating medium is producible on the wood material board by the targeted and individual control of the individual applicator devices (13).
5. Plant according to claim 4, characterized in that the produced patterns are formed rectangular, square, diamond-shaped, trapezoid, and/or circular.
6. Plant according to claim 1, characterized in that the applicator heads (14) are arranged in two parallel rows over the full width of the transport device (11), and wherein the spacing between the two rows is optionally changeable,

   and/or that furthermore a processor for actuating the control elements (16) of the applicator devices (13)

   and/or for actuating the suction devices (15)

   and/or for actuating the transport device (11) is provided.
7. Plant according to at least one of the preceding claims, characterized in that the applicator heads (14) are split applicator heads (14).
8. Plant according to claim 7, characterized in that the control of the pressure and application quantity are variable for the respective split applicator heads (14), whereby the impregnations are controllable in their geometry.
9. Method for impregnating of material boards (1), especially wood fibre-boards, in which individual material boards (1) that have been previously pressed, or a continuous material board string consisting of previously pressed cakes, are placed on a transport device (11) in such a way that the individual material boards (1) are arranged one behind the other as an endless string of material boards lying on the transport device (11), or that the continuous material board string is lying on the transport device (11),

   that the string of single material boards (1) or the continuous material board string is led continuously through an impregnating station (12) for the introduction of an impregnating medium into the material boards (1) or the material board string,

   wherein the impregnating medium is applied by means of a plurality of applicator devices (13) in the form of applicator heads (14) which are arranged in at least one row across the full width of the individual material board (1) or of the continuous material board string, wherein individual applicator devices (13) that are selectable from the plurality of applicator devices (13), individually controllable, and/or are differently operable in respect of the quantity applied, time-controlled during the continued transporting of the individual material boards (1) of the string or of the continuous material board string,

   and wherein

   almost any pattern of the impregnating medium on the wood material board is produced by the targeted and individual control of the individual applicator devices (13), and the applicator heads (14) press the impregnating medium into the depth of the material boards (1) by means of overpressure.
10. Method according to claim 9, characterized in that the produced patterns are rectangles, squares, diamond shapes, trapezoids or circles.
11. Method according to at least one of the claims 9 to 10, characterized in that the impregnating medium is introduced into the depth of the material board (1) by means of an underpressure that takes effect from the underside of the transport device (11) through openings in the transport device (11).
12. Method according to claim 11, characterized in that the application of the impregnating medium to and the introduction into the material board (1) is individually designed, and any patterns are formed on the surface and in the depth of the material board (1).
13. Method according to at least one of the claims 9 to 12, characterized in that applicator heads (14) in the form of split applicator heads (14) are used, wherein the control of the pressure and of the application quantity is variable for each of the respective split applicator heads (14).
14. Method according to claim 13, characterized in that by means of the split applicator heads (14) multiple impregnations and impregnations with multi-component materials are performed.
15. Method according to one of the preceding claims 9 to 12, characterized in that the individual applicator devices (13) of the plurality of applicator devices (13) are so controlled as a function of time that each individual applicator device (13) only gives out impregnating medium at a preselected point in time and/or that the time-dependent control of the applicator devices (13) is synchronized with the transport speed of the individual material boards (1) of the string or of the continuous material board string, wherein the transport of the continuous string of material boards (1) take place by means of the transport device (11),

    and/or the time-dependent control of the applicator devices (13) and/or the synchronization of the transport device (11) is controlled and/or regulated by a processor

    and/or the spatial distribution of the impregnating medium in the depth of the material board (1) is controlled by presetting the overpressure in the applicator device (13) and/or the underpressure, taking effect on the material board (1) from the other side, accordingly

    and/or the impregnating medium is used in liquid, dissolved or suspended form, or as an emulsion

    and/or the impregnating medium changes the water absorption

    and/or the swelling and/or the strength values

    and/or the flammability of the material board (1)

    and/or that the material boards (1) are made of wood materials, of min-erally bonded wood materials, or of mineral materials, or of a combination of these materials, or contains them.

Images