EP1110687B1 - Process for producing a light weight fibre board with a closed surface, and board so produced - Google Patents

Process for producing a light weight fibre board with a closed surface, and board so produced Download PDF

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Publication number
EP1110687B1
EP1110687B1 EP00124199A EP00124199A EP1110687B1 EP 1110687 B1 EP1110687 B1 EP 1110687B1 EP 00124199 A EP00124199 A EP 00124199A EP 00124199 A EP00124199 A EP 00124199A EP 1110687 B1 EP1110687 B1 EP 1110687B1
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Prior art keywords
binder
bulk density
fibre
fibres
fibers
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German (de)
French (fr)
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EP1110687A1 (en
EP1110687B2 (en
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Michael Dr. Müller
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Glunz AG
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Glunz AG
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B27WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
    • B27NMANUFACTURE BY DRY PROCESSES OF ARTICLES, WITH OR WITHOUT ORGANIC BINDING AGENTS, MADE FROM PARTICLES OR FIBRES CONSISTING OF WOOD OR OTHER LIGNOCELLULOSIC OR LIKE ORGANIC MATERIAL
    • B27N3/00Manufacture of substantially flat articles, e.g. boards, from particles or fibres
    • B27N3/005Manufacture of substantially flat articles, e.g. boards, from particles or fibres and foam
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B27WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
    • B27NMANUFACTURE BY DRY PROCESSES OF ARTICLES, WITH OR WITHOUT ORGANIC BINDING AGENTS, MADE FROM PARTICLES OR FIBRES CONSISTING OF WOOD OR OTHER LIGNOCELLULOSIC OR LIKE ORGANIC MATERIAL
    • B27N3/00Manufacture of substantially flat articles, e.g. boards, from particles or fibres
    • B27N3/08Moulding or pressing

Definitions

  • the invention relates to a process for the preparation a lightweight fiberboard according to the preamble of the claim 1 and on a lightweight fiberboard according to the preamble of patent claim 15.
  • the invention relates a lot to fiberboard low density, in particular as insulating material, but also as Design elements can be used, and on their Production.
  • a typical representative of known fiberboard the aforementioned field of application are so-called wood soft fiber boards.
  • a so-called dry process for the production of fiberboards from lignocellulosic fibers and binders is known.
  • the fibers are obtained in the same way as for the wet process. Subsequently, however, they are not transferred into a suspension, but dried in current dryers, ie in flight, to a level that later allows easier removal of the residual moisture.
  • the residual moisture content of the fibers after drying is less than 20%, typically less than 10%.
  • a binder is added to the fibers, which, after the subsequent shaping of the fibers into a fiber mat during hot pressing of the fiber mat between pressure-controlled heating surfaces to a fiberboard, glues the individual fibers together.
  • Dry-laid fibreboards are subdivided into high-density fibreboard (HDF), medium-density fibreboard (MDF), light and ultra-light fibreboard (ULF) within a density range of 900 to 450 kg per m 3 .
  • Characteristic of fiberboard according to the known dry process is that even with so-called ultra-light fibreboard (ULF) due to the still relatively high density no good insulation effects are achieved and when using the fiberboard as construction elements, the relatively high weight of the fiberboard is taken into account.
  • ULF ultra-light fibreboard
  • these known fiberboard on smooth closed surfaces that are directly coated even with thin materials.
  • the activation of the binder should be done for example by steam. To harden the fiber mat, this is to be flowed through with a drying medium, for example with hot air. If a thickness formation takes place in a press, the pressing surfaces should be designed like a sieve. In this way, as in a wet process fiberboard with open and structured by the screen surfaces used surface are produced, which thus also have all the disadvantages of known produced in the wet process fiberboard.
  • a process for the production of polyurethane-bonded fiberboard is known, which is classified as a special dry process.
  • the known method makes use of a binder having a first, NCO-containing binder component and a second, at least one polyol-containing binder component.
  • the at least two binder components are applied separately or at least without significant pre-reaction in the mixture on fibers, so that the polyurethane bond takes place as late as possible in the manufacturing process and thus substantially during a hot pressing as a heat treatment.
  • the second binder component comprising the polyol is applied to the fibers, while the first NCO-containing binder component is applied to the same fibers only thereafter and as late as possible before the fibers are formed into the fiber mat.
  • the binder components for the polyurethane bond or suppressing a pre-reaction of the binder components the entire reactivity of the binder for the bonding of the fibers during hot pressing of the fiber mat to the fiberboard should be maintained. Namely, it is known that the polyurethane reaction between the binder component containing the NCO groups and the binder component containing the polyol spontaneously starts when these two binder components come together unless it is chemically blocked.
  • the invention has for its object to provide a method for Production of light fiberboard according to the preamble of Claim 1 show that simple and economical is feasible and yet improved to fiberboard with Surface properties leads. Furthermore, a slight Fiberboard according to the preamble of claim 15 be shown, the improved surface properties having.
  • Advantageous embodiments of the method are in the Subclaims 2 to 15 and advantageous embodiments of Fiber board described in the subclaims 16 to 20.
  • the new process is a dry process because the fiber moisture content of the fibers is less than 20% when calibrating the fiber mat and during the heat treatment to cure the binder. It can be in the range below 10% as with conventional dry processes.
  • the heat treatment of the fiber mat via smooth closed heating surfaces, via which the heat is transferred to the curing of the binder on the fiber mat. It is important that the heating surfaces are distance-controlled and not pressure-controlled, as is the case when carrying out conventional drying processes.
  • the very low bulk density of the fiber boards produced by the new process does not allow controlled pressure control of the heating surfaces.
  • the fiber mat before heat treatment with To spray water or an aqueous solution.
  • To spray water or an aqueous solution In this way can be steamed by water evaporating on the heating surfaces be directed into the interior of the fiber mat, there the Curing of the binder promotes.
  • the water gives way to the Fibers on the surface of the fiber mat, so that through the Influence of smooth heating surfaces particularly good smooth surfaces can be achieved in the finished fiberboard.
  • the fiber mat through the spaced controlled heating surfaces also be calibrated.
  • the thickness of the is typically 20 up to 300 mm. It's just in the area of bigger thicknesses in This area amazing that the fiberboard still after can be produced by a dry process.
  • the Density profile of the fiberboard is adjusted so that an edge exaggeration of the density compared to the middle Density of the fiberboard of at least 60% results.
  • a Stronger marginal increase in density is the basis for the Forming a particularly strong closed surface of finished fiberboard, for example, a considerable Pressure stability compared to the average density of the Can have fiberboard.
  • a common synthetic resin of the wood-based material industry can be used as the binder.
  • the usual synthetic resins of the wood-based materials industry include urea-formaldehyde, melamine-urea-formaldehyde, melamine-urea-phenol-formaldehyde, phenol-urea-formaldehyde, phenol-formaldehyde and PMDI resins.
  • a foaming polyurethane binder may be used as the binder.
  • the advantage of filling the voids in the fiberboard between the individual fibers by the polyurethane foam is no longer noticeable in an economically utilizable way.
  • the particularly light fiberboard in the range below 150 kg / m 3 but can not be produced in usable quality without the use of a foam-forming binder.
  • foam-forming polyurethane binder may be a so-called One-component system are used, which for example was developed by the company Bayer and basically is available.
  • foam-forming Polyurethane binders a first, having NCO groups Binder component and a second at least one polyol comprising binder component.
  • the fibers before applying the Binder divided into at least two batches and on a first of these games only the first having the NCO groups Binder component and on a second of these parts only the second, the polyol-containing binder component to apply and the parts of the fibers only just before molding to mix the fiber mat together.
  • the two binder components so completely separated from each other. Also during mixing The parts of the fibers are not yet worth mentioning Contact of the two binder components. Only when molding the Fiber mat turns this contact at the contact points of the Fibers. But this contact is still not enough to alone trigger a significant amount of polyurethane reaction.
  • the first batch can basically be 10 up to 90% and the second batch corresponding to 90 to 10% of the contain entire fibers. But it makes sense if the first and second parts of the fibers are about the same size are, d. H. For example, each 40 to 60% of the total Contain fibers.
  • the new process can be both discontinuous as well be carried out continuously, which is preferred.
  • at continuous process control are the heating surfaces typically at rear heated metal endless belts intended.
  • the batches of fibers can Binder components and before mixing them separately be stored by each other.
  • the reactivity of the Binder components increases in separate storage of the Part of the fibers does not decrease even for longer periods of time.
  • the heat treatment can be made be that in the middle of the molding a temperature of only 50 to 100 ° C is reached. That means that compared to known methods very low temperatures in the middle of the Shaped body are sufficient. These result inversely in a high efficiency of the used in the heat treatment Energy and short periods of time for the heat treatment needed.
  • the low temperature is at the new Process at least then for the curing of the binder content in the middle of the molding sufficient if highly reactive polyurethane binders are used, whose Reaction is not chemically hindered to a pre-reaction suppress.
  • the fibers used in the new process be processed, wood fibers in the form of conventional Defibratormaschinestoff.
  • the binder content can be far in the new process Borders are selected by the necessary strength of the Fiberboard on the one hand and the economy of the Process face high binder costs on the other hand are set.
  • the following information refers to the Use of a polyurethane binder.
  • the average density of the shaped body is adjusted to 60 to 250 kg per m 3 , wherein the binder content of the molding is adjusted to a total of 2.5 to 5% by weight based on atro wood fibers.
  • the average density of the molding is adjusted to 250 to 400 kg / m 3 , wherein the binder content of the molding is adjusted to a total of 7 to 15% by weight based on atro wood fibers.
  • the new method can also be carried out so that the Forming the preform from the fibers using a layer construction different compositions and / or proportions of Binder is set in each layer. So for example, the binder levels in the topcoats a fiberboard be larger than in the middle layer, to a particularly high stability of the outer layers too to reach. But there are also other layer structures for Adaptation to specific requirement profiles with the new procedure realizable. It is understood that lots of Fibers used for different layers of the layer structure are provided, not with each other before forming the fiber mat but only those fibers that are mixed for each provided a layer of uniform composition are.
  • mechanically stable fiberboards result using a foam-forming binder, ie a polyurethane binder which has at least two binder components PMDI and polyol or which is a one-component system.
  • a foam-forming binder ie a polyurethane binder which has at least two binder components PMDI and polyol or which is a one-component system.
  • Such fiber boards may also be considered fiber stabilized polyurethane foam.
  • the binder content of atro fibers is at least 5%, so in absolute terms it is still relatively small.
  • binder content can be reduced when using a foam-forming polyurethane binder below 5% atro fibers. If the stabilities are not paramount, binder levels down to within 1% may be sufficient. All percentages are, as usual, weight percentages.
  • binder content should also be selected for lower strengths above 5%, and for higher strengths 7 to 15% binder content should be used.
  • a foam-forming binder can be used, in which case high-strength fiberboard can be produced even with relatively low binder levels.
  • the method illustrated in the flow chart of the figure for the production of polyurethane-bound molded body goes from wood 1, which is comminuted in the usual way and then in a defibrator 2 in individual wood fibers 3 is digested. The stream of wood fibers 3 is then in a Dividing device 4 divided into two parts 5 and 6, wherein the games 5 and 6 are the same size. On the wood fibers 3 of the Lot 5 becomes in an applicator 7 an NCO groups containing binder component 8, a so-called PMDI, applied.
  • the formulation of PMDI 8 corresponds to one such as those commonly used in the wood-based panel industry sole binder is used.
  • one at least one Polyol-containing binder component 10 applied on the wood fibers 3 of the Lot 6 is in an applicator 9 one at least one Polyol-containing binder component 10 applied.
  • it is preferably a mixture of short chain with a long-chain polyol.
  • a mixture one part of diethylene glycol and one part of polyether alcohol the molecular weight 1000 can be used.
  • Both application devices 7 and 9 work on the principle that the PMDI 8 and the polyol 10th is sprayed onto the wood fibers 3.
  • the Lots 5 and 6 if necessary in separate buffers 11 and 12 intermediately stored. These may be conventional wood fiber bunkers act.
  • An intermediate storage is basically optional and does not have to be mandatory.
  • a mixing device 13 the wood fibers 3 of the Batches 5 and 6 mixed together. With a suitable combination the streams of lots 5 and 6 may be the required mixing also by rolling a scattering head a scattering device 14 done. From the wood fibers 3 both Batches 5 and 6 becomes a fiber mat in the spreader 14 15, which is a preform of fiberboard produced here 18 represents. The fiber mat 15 is in a calibration device 16 calibrated, which is a cold pre-compression Prepress is. Subsequently, in a Hot press 17 a heat treatment from which the desired Fiberboard 18 results.
  • the hot press 17 is not so to understand that the fiber mat 15 under application compressed by pressure. Rather, the plates are the Hot press 17 distance-controlled, even without a constant back pressure the fiber mat 15 to fiber plates 18 with a defined thickness get.
  • the new process can be done with both a belt press as a hot press 17 as well as with a discontinuous working Hot press to be performed. It can be beneficial instead of or alternatively to hot contact surfaces also a Hot air heating or high frequency heating of the calibrated Fiber mat 15 provide. When warming over hot contact surfaces, it is advantageous to the surfaces of Sprinkle fiber mat 15 with water, so that on the hot Contact surfaces evaporating water heat also into the interior of the Fiber mat 15 transfers. This is especially beneficial if the fiber mat 15 is very thick, d. H. more than 40 mm thick.
  • the following examples have in common that the PMDI used, d. H. the NCO group-containing binder component, a Had composition, as used in the wood-based panel industry is common.
  • the second polyol component binder component was the already mentioned above mixture of one Part of diethylene glycol and one part of polyether alcohol of molecular weight 1000.
  • As a mixing device 13 came a simple rotary drum for use.
  • the mixing time of the two games 5 and 6 was 10 seconds.
  • the temperature of the contact surfaces of Hot press 17 was set at 170 ° C. All% information is in weight%.
  • the PMDI 8 was used in a proportion of 2.5% and the polyol 10 in a proportion of 1% based on atro wood fibers 3. After 240 sec. Dwell time of the fiber mat 15 in the hot press 17, a 100 mm thick fiber plate 18 was removed. The average bulk density of this fiberboard 18 was 80 kg / m 3 . Despite the very low compression of the wood fibers in this fiber board, the fiber board for an insulating material was perfectly stable and manageable.
  • the binder proportions corresponded to Example 1. After 300 sec. Dwell time of the fiber mat 15 in the hot press 17, a 50 mm thick fiber plate 18 was removed. The average bulk density was 170 kg / m 3 . The flexural strength of the fiberboard 18 was 0.3 N / mm 2 . The compressive stress at 10% compression was 0.18 N / m 2 .

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Wood Science & Technology (AREA)
  • Forests & Forestry (AREA)
  • Dry Formation Of Fiberboard And The Like (AREA)
  • Laminated Bodies (AREA)

Abstract

Moldings from lignocellulose particles, bound with polyurethane by applying binder component (I) containing isocyanate (NCO) groups and binder component(s) (II) containing polyol(s) to the particles separately, preforming, calibration and heating to initiate the polyurethane reaction of the binder. The particles are first divided into >= 2 batches, (I) is applied to one batch and (II) to the other and the batches are mixed before molding to the preform.

Description

Die Erfindung bezieht sich auf ein Verfahren zur Herstellung einer leichten Faserplatte nach dem Oberbegriff des Patentanspruchs 1 und auf eine leichte Faserplatte nach dem Oberbegriff des Patentanspruchs 15.The invention relates to a process for the preparation a lightweight fiberboard according to the preamble of the claim 1 and on a lightweight fiberboard according to the preamble of patent claim 15.

Anders gesagt bezieht sich die Erfindung auf Faserplatten sehr geringer Dichte, die insbesondere als Dämmaterial, aber auch als Konstruktionselemente Verwendung finden können, und auf deren Herstellung. Ein typischer Vertreter von bekannten Faserplatten des vorgenannten Anwendungsbereichs sind sogenannte Holzweichfaserplatten.In other words, the invention relates a lot to fiberboard low density, in particular as insulating material, but also as Design elements can be used, and on their Production. A typical representative of known fiberboard the aforementioned field of application are so-called wood soft fiber boards.

Zur Herstellung von Holzweichfaserplatten ist ein Naßverfahren bekannt. Durch mahlenden, schleifende oder quetschende Krafteinwirkung aus Holz hergestellte Fasern werden in eine wässrige Suspension überführt, die typischerweise nur 2 bis 3 Gewichts-% Fasern enthält. Diese Suspension mit dem maximal gequollenen Fasern wird auf ein Siebband aufgebracht, durch das eine Entwässerung zunächst mittels Schwerkraft und anschließend über verschiedene Saug- und Vorpreßeinrichtungen erfolgt. Der dabei erreichbare Entwässerungsgrad wird durch das Wasserspeichervermögen der gequollenen Fasern und die angesichts der angestrebten geringen Dichte der späteren Faserplatten nur geringen zulässigen Preßkräfte nach unten begrenzt. Die durch die Vorentwässerung der Suspension erhaltene Fasermatte aus feuchten Fasern wird nach ihrem Kalibrieren drucklos getrocknet. Bei der Trocknung schrumpfen die einzelnen Holzfasern aneinander fest, sofern kein Bindemittel eingesetzt wird. Wenn ein Bindemittel eingesetzt wird, so daß es sich bei dem bekannten Verfahren um ein solches nach dem Oberbegriff des Patentanspruchs 1 handelt, ist darauf zu achten, daß sich das Bindemittel an den Holzfasern fixiert, da es anderenfalls mit dem Wasser der Ausgangssuspension abgesaugt bzw. abgepreßt wird. Die nach dem bekannten Naßverfahren erhaltenen Faserplatten können zwar die gewünschte geringe Dichte aufweisen. Sie weisen aber eine locker offene Oberfläche, die für viele Anwendungszwecke wenig geeignet ist, auf. Beispielsweise können nach dem Naßverfahren hergestellte Faserplatten, die als Dämmplatten im Innenausbau verwendet werden, nicht ohne weiteres tapeziert oder anderweitig mit dünnen Materialien beschichtet werden. Hierbei drückt sich zu leicht die auf die Struktur des bei ihrer Herstellung verwendeten Siebbands zurückgehende Struktur der Oberfläche der Faserplatten durch, und eingesetzte Bindemittel werden zu großen Anteilen in das Volumen der Faserplatten eingesaugt und stehen damit nicht für die Befestigung der Tapete oder des anderen dünnen Materials an der Oberfläche der Faserplatte zur Verfügung.For the production of soft wood fiber boards is a wet process known. By grinding, grinding or squeezing force fibers made of wood are turned into an aqueous Suspension, which is typically only 2 to 3% by weight Contains fibers. This suspension with the maximum swollen Fibers are applied to a screen belt through which a Drainage first by gravity and then over various suction and Vorpreßeinrichtungen done. The case achievable degree of drainage is due to the water storage capacity the swollen fibers and the face of the aimed at low density of later fiberboard only limited permissible compression forces downwards. By the pre-dewatering of the suspension obtained fiber mat moist fibers are dried without pressure after their calibration. During drying, the individual wood fibers shrink fixed, if no binder is used. If a binder is used, so that it is in the known method to such after the preamble of claim 1 Care must be taken to ensure that the binder to the Fibers are fixed, otherwise it is with the water of the Suction suspension is sucked or pressed. The after the Although known wet process obtained fiberboard can indeed have desired low density. But they have a loose open surface, which is unsuitable for many applications is on. For example, after the wet process manufactured fiberboard used as insulation panels in interior design used, not readily papered or otherwise be coated with thin materials. This expresses itself too easy the on the structure of in their preparation used sieve bands returning surface structure Fiberboard through, and used binders are too large Shares sucked into the volume of fiberboard and stand so as not for the attachment of wallpaper or other thin Materials available on the surface of the fiberboard.

Neben dem Naßverfahren ist ein sogenanntes Trockenverfahren zur Herstellung von Faserplatten aus lignocellulose-haltigen Fasern und Bindemittel bekannt. Die Fasern werden hierfür in derselben Weise wie für das Naßverfahren gewonnen. Anschließend werden sie jedoch nicht in eine Suspension überführt, sondern in Stromtrocknern, d. h. im Flug, auf ein Maß heruntergetrocknet, welches später eine einfachere Entfernung der Restfeuchte ermöglicht. Die Restfeuchte der Fasern nach der Trocknung liegt unter 20 %, typischerweise bei unter 10 %. Vor oder nach der Trocknung wird den Fasern ein Bindemittel zugesetzt, das nach dem anschließenden Formen der Fasern zu einer Fasermatte beim Heißverpressen der Fasermatte zwischen druckgesteuerten Heizflächen zu einer Faserplatte die einzelnen Fasern miteinander verklebt. Faserplatten nach dem Trockenverfahren werden innerhalb eines Dichtebereichs von 900 bis 450 kg pro m3 in hochdichte Faserplatten (HDF), mitteldichte Faserplatten (MDF), leichte und ultraleichte Faserplatten (ULF) unterteilt. Charakteristisch für Faserplatten nach dem bekannten Trockenverfahren ist, daß selbst bei sogenannten ultraleichten Faserplatten (ULF) aufgrund der immer noch relativ hohen Dichte keine ausreichend guten Dämmwirkungen erreicht werden und bei der Verwendung der Faserplatten als Konstruktionselemente das relativ hohe Eigengewicht der Faserplatten zu berücksichtigen ist. Allerdings weisen diese bekannten Faserplatten glatt geschlossene Oberflächen auf, die auch mit dünnen Materialien direkt beschichtbar sind.In addition to the wet process, a so-called dry process for the production of fiberboards from lignocellulosic fibers and binders is known. The fibers are obtained in the same way as for the wet process. Subsequently, however, they are not transferred into a suspension, but dried in current dryers, ie in flight, to a level that later allows easier removal of the residual moisture. The residual moisture content of the fibers after drying is less than 20%, typically less than 10%. Before or after drying, a binder is added to the fibers, which, after the subsequent shaping of the fibers into a fiber mat during hot pressing of the fiber mat between pressure-controlled heating surfaces to a fiberboard, glues the individual fibers together. Dry-laid fibreboards are subdivided into high-density fibreboard (HDF), medium-density fibreboard (MDF), light and ultra-light fibreboard (ULF) within a density range of 900 to 450 kg per m 3 . Characteristic of fiberboard according to the known dry process is that even with so-called ultra-light fibreboard (ULF) due to the still relatively high density no good insulation effects are achieved and when using the fiberboard as construction elements, the relatively high weight of the fiberboard is taken into account. However, these known fiberboard on smooth closed surfaces that are directly coated even with thin materials.

Weiterhin ist ein sogenanntes Semi-Dry-Verfahren bekannt, bei dem die zunächst wie beim Trockenverfahren getrockneten Fasern nach der Ausbildung einer Fasermatte wieder befeuchtet und anschließend heiß verpreßt werden. Auf diese Weise wird bei relativ leichten Faserplatten im Bereich oberhalb 450 kg/m3 eine besonders feste, glatt geschlossene Oberfläche erzielt.Furthermore, a so-called semi-dry process is known in which the first dried as in the dry process fibers after the formation of a fiber mat moistened again and then pressed hot. In this way, with relatively light fiberboard in the range above 450 kg / m 3, a particularly firm, smoothly closed surface is achieved.

Aus der DE 196 74 240 A1 ist ein Verfahren zur Herstellung von Faserplatten bekannt, das auch zwischen einem echten Naßverfahren und einem Trockenverfahren anzuordnen ist. Mit diesem bekannten Verfahren sind Faserplatten mit einer geringen Dichte von bis weit unter 150 kg/m3, angeblich bis hinab zu 60 kg/m3 hergestellbar. Hierzu werden aus Holz hergestellte Fasern, deren Feuchtigkeitsgehalt nach einem einen Zerfaserungsprozeß abschließenden Refiner-Verfahren unverändert bleibt, mit einem Bindemittel vermischt und mit einer Streuvorrichtung auf einer Formstation ausgebracht, um eine Fasermatte auszubilden. Die Fasermatte wird hinsichtlich ihrer Breite und ihres Flächengewichts vorkalibriert und nach Aktivierung des Bindemittels durch eine Wärmebehandlung zur Bildung der Faserplatte in der Dicke geformt und ausgehärtet. Die Aktivierung des Bindemittels soll dabei beispielsweise durch Dampf erfolgen. Zum Aushärten der Fasermatte soll diese mit einem Trocknungsmedium, beispielsweise mit Heißluft durchströmt werden. Wenn eine Dickenformung in einer Presse erfolgt, sollen die Preßflächen siebartig ausgebildet sein. Auf diese Weise werden wie bei einem Naßverfahren Faserplatten mit offener und durch die eingesetzten Siebflächen strukturierter Oberfläche hergestellt, die so auch alle Nachteile bekannter im Naßverfahren hergestellter Faserplatten aufweisen.From DE 196 74 240 A1 a process for the production of fiberboard is known which is also to be arranged between a real wet process and a dry process. With this known method, fibreboards with a low density of up to well below 150 kg / m 3 , allegedly down to 60 kg / m 3 can be produced. For this purpose, fibers made of wood, the moisture content of which remains unchanged after a refiner process which concludes a defibration process, are mixed with a binder and applied to a forming station with a spreader to form a fiber mat. The fiber mat is precalibrated in width and basis weight and shaped and cured after activation of the binder by a heat treatment to form the fiberboard. The activation of the binder should be done for example by steam. To harden the fiber mat, this is to be flowed through with a drying medium, for example with hot air. If a thickness formation takes place in a press, the pressing surfaces should be designed like a sieve. In this way, as in a wet process fiberboard with open and structured by the screen surfaces used surface are produced, which thus also have all the disadvantages of known produced in the wet process fiberboard.

Aus der DE 196 04 575 A1 ist ein Verfahren zur Herstellung polyurethangebundener Faserplatten bekannt, das als spezielles Trockenverfahren einzuordnen ist. Das bekannte Verfahren macht von einem Bindemittel mit einer ersten, NCO-Gruppen aufweisenden Bindemittelkomponente und einer zweiten, mindestens ein Polyol aufweisenden Bindemittelkomponente Verwendung. Hierbei werden die mindestens zwei Bindemittelkomponenten separat oder zumindest ohne nennenswerte Vorreaktion im Gemisch auf Fasern aufgebracht, so daß die Polyurethanbindung möglichst spät im Herstellungsprozeß und damit im wesentlichen während eines Heißpressens als Wärmebehandlung erfolgt. Zur separaten Aufbringung der beiden Bindemittelkomponenten wird beispielsweise zunächst die das Polyol aufweisende zweite Bindemittelkomponente auf die Fasern aufgebracht, während die erste, NCO-Gruppen aufweisende Bindemittelkomponente erst danach und möglichst spät vor dem Formen der Fasern zu der Fasermatte auf dieselben Fasern aufgebracht wird. Durch das separate Aufbringen der Bindemittelkomponenten für die Polyurethanbindung bzw. das Unterdrücken einer Vorreaktion der Bindemittelkomponenten soll die gesamte Reaktivität des Bindemittels für die Bindung der Fasern beim Heißverpressen der Fasermatte zu den Faserplatten erhalten bleiben. Es ist nämlich bekannt, daß die Polyurethanreaktion zwischen der die NCO-Gruppen enthaltenen Bindemittelkomponente und der das Polyol aufweisenden Bindemittelkomponente beim Zusammentreffen dieser beiden Bindemittelkomponenten spontan beginnt, sofern sie nicht chemisch blockiert wird. Hierdurch ist die Topfzeit von Mischungen der beiden Bindemittelkomponenten eng begrenzt. Bei einer chemischen Blockade der Polyurethanreaktion müssen umgekehrt durch die Wärmebehandlung zum Auslösen der Polyurethanreaktion des Bindemittels in der Fasermatte sehr hohe Reaktionstemperaturen erreicht werden. Das aus der DE 196 04 575 A1 bekannte Verfahren weist den Nachteil auf, daß unmittelbar nachdem beide Bindemittelkomponenten auf die Fasern aufgebracht sind, die Polyurethanreaktion einsetzt. Das heißt, der Zeitraum zwischen dem Aufbringen der beiden Bindemittelkomponenten auf die Fasern und der Wärmebehandlung zum Aushärten des Bindemittelanteils der gewünschten Faserplatten muß möglichst kurz gehalten werden. Unterbrechungen des Herstellungsprozesses im Bereich des Formens der Fasern zu der Fasermatte, des Kalibrierens der Fasermatte, und der Wärmebehandlung führen dazu, daß die Polyurethanreaktion auf den Fasern so weit fortschreitet, daß sie verworfen werden müssen. Eine Zwischenlagerung ist nicht möglich. Darüberhinaus besteht die Gefahr, daß Fasern im angehaltenen Stoffstrom untereinander soweit verkleben, daß Herstellungsapparaturen verstopfen und aufwendig gereinigt werden müssen. Die Rohdichten der nach dem bekannten Verfahren hergestellten polyurethangebundenen Faserplatten liegen im übliche Bereich weit oberhalb von 450 kg/m3.From DE 196 04 575 A1 a process for the production of polyurethane-bonded fiberboard is known, which is classified as a special dry process. The known method makes use of a binder having a first, NCO-containing binder component and a second, at least one polyol-containing binder component. Here, the at least two binder components are applied separately or at least without significant pre-reaction in the mixture on fibers, so that the polyurethane bond takes place as late as possible in the manufacturing process and thus substantially during a hot pressing as a heat treatment. For separate application of the two binder components, for example, first the second binder component comprising the polyol is applied to the fibers, while the first NCO-containing binder component is applied to the same fibers only thereafter and as late as possible before the fibers are formed into the fiber mat. By separately applying the binder components for the polyurethane bond or suppressing a pre-reaction of the binder components, the entire reactivity of the binder for the bonding of the fibers during hot pressing of the fiber mat to the fiberboard should be maintained. Namely, it is known that the polyurethane reaction between the binder component containing the NCO groups and the binder component containing the polyol spontaneously starts when these two binder components come together unless it is chemically blocked. As a result, the pot life of mixtures of the two binder components is limited. Conversely, in the case of a chemical blockade of the polyurethane reaction, very high reaction temperatures must be achieved by the heat treatment for triggering the polyurethane reaction of the binder in the fiber mat. The process known from DE 196 04 575 A1 has the disadvantage that immediately after both binder components have been applied to the fibers, the polyurethane reaction is used. That is, the period between the application of the two binder components to the fibers and the heat treatment for curing the binder content of the desired fiberboard must be kept as short as possible. Interruptions in the manufacturing process in the area of forming the fibers to the fiber mat, calibrating the fiber mat, and the heat treatment cause the polyurethane reaction on the fibers to progress so far that they must be discarded. A temporary storage is not possible. In addition, there is a risk that fibers in the suspended material flow stick together so far that production equipment clog and must be cleaned consuming. The bulk densities of the polyurethane-bonded fiberboards produced by the known process are in the usual range well above 450 kg / m 3 .

Der Erfindung liegt die Aufgabe zugrunde, ein Verfahren zur Herstellung leichter Faserplatten nach dem Oberbegriff des Patentanspruchs 1 aufzuzeigen, das einfach und wirtschaftlich durchführbar ist und dennoch zu Faserplatten mit verbesserten Oberflächeneigenschaften führt. Weiterhin soll eine leichte Faserplatte nach dem Oberbegriff des Patentanspruchs 15 aufgezeigt werden, die verbesserte Oberflächeneigenschaften aufweist. The invention has for its object to provide a method for Production of light fiberboard according to the preamble of Claim 1 show that simple and economical is feasible and yet improved to fiberboard with Surface properties leads. Furthermore, a slight Fiberboard according to the preamble of claim 15 be shown, the improved surface properties having.

Erfindungsgemäß wird diese Aufgabe durch das Verfahren nach dem Patentanspruch 1 und die Faserplatte nach dem Patentanspruch 15 gelöst.According to the invention, this object is achieved by the method according to Claim 1 and the fiberboard according to claim 15 solved.

Vorteilhafte Ausführungsformen des Verfahrens sind in den Unteransprüchen 2 bis 15 und vorteilhafte Ausführungsformen der Faserplatte in den Unteransprüchen 16 bis 20 beschrieben.Advantageous embodiments of the method are in the Subclaims 2 to 15 and advantageous embodiments of Fiber board described in the subclaims 16 to 20.

Bei dem neuen Verfahren handelt es sich trotz der erreichten geringen mittleren Rohdichte von unter 400 kg/m3 um ein Trockenverfahren, weil die Faserfeuchte der Fasern beim Kalibrieren der Fasermatte und bei der Wärmebehandlung zum Aushärten des Bindemittels weniger als 20 % beträgt. Sie kann wie bei üblichen Trockenverfahren im Bereich unter 10 % liegen. Wie bei einem klassischen Trockenverfahren erfolgt die Wärmebehandlung der Fasermatte über glatt geschlossene Heizflächen, über die die Wärme zur Aushärtung des Bindemittels auf die Fasermatte übertragen wird. Wichtig dabei ist, daß die Heizflächen distanzgesteuert werden und nicht etwa druckgesteuert, wie dies bei Durchführung üblicher Trockenverfahren der Fall ist. Die sehr geringe Rohdichte der nach dem neuen Verfahren hergestellten Faserplatten läßt keine kontrollierte Drucksteuerung der Heizflächen zu. Durch die Distanzsteuerung der Heizflächen wird den hergestellten Faserplatten aber dennoch ein Rohdichteprofil aufgeprägt, das eine Randüberhöhung der Rohdichte gegenüber der mittleren Rohdichte der Faserplatten von mindestens 20 % aufweist. Die Randbereiche der Faserplatten sind damit gegenüber ihrer mittleren Rohdichte verdichtet. In Verbindung mit den glatt geschlossenen Heizflächen, die diese Verdichtung hervorrufen ergibt sich so eine glatt geschlossene Oberfläche der hergestellten Faserplatten. Diese glatt geschlossene Oberfläche ist für Faserplatten im Dichtebereich unter 400 kg/m3 ein absolutes Novum. So sind hocheffektive Wärmedämmplatten für den Innenausbau herstellbar, die direkt übertapeziert werden können. Die glatt geschlossene Oberfläche der neuen Faserplatten macht sich auch bei anderen Anwendungen sehr vorteilhaft bemerkbar. Despite the low average bulk density of less than 400 kg / m 3 achieved, the new process is a dry process because the fiber moisture content of the fibers is less than 20% when calibrating the fiber mat and during the heat treatment to cure the binder. It can be in the range below 10% as with conventional dry processes. As with a traditional dry process, the heat treatment of the fiber mat via smooth closed heating surfaces, via which the heat is transferred to the curing of the binder on the fiber mat. It is important that the heating surfaces are distance-controlled and not pressure-controlled, as is the case when carrying out conventional drying processes. The very low bulk density of the fiber boards produced by the new process does not allow controlled pressure control of the heating surfaces. Due to the distance control of the heating surfaces, however, a density profile is impressed on the fiberboards produced which has an edge increase of the bulk density compared with the average bulk density of the fiberboards of at least 20%. The edge regions of the fiberboard are thus compressed compared to their average density. In conjunction with the smooth heating surfaces that cause this compaction results in a smooth closed surface of the fiberboard produced. This smoothly closed surface is an absolute novelty for fiberboard in the density range below 400 kg / m 3 . Thus, highly effective thermal insulation panels for interior work can be produced, which can be directly over-wallpapered. The smooth closed surface of the new fiberboard is also very beneficial in other applications.

Bei dem neuen Verfahren ist nicht zu übersehen, daß die geringe Dichte, die auch schon bei der Fasermatte vorliegt, einen Wärmeübertrag bis in die Mitte der Fasermatte während der Wärmebehandlung nicht gerade erleichtert. Deshalb ist es bei dem neuen Verfahren bevorzugt, die Fasermatte vor der Wärmebehandlung mit Wasser oder einer wässrigen Lösung zu besprühen. Auf diese Weise kann durch an den Heizflächen verdampfendes Wasser ein Dampfstoß in das Innere der Fasermatte gerichtet werden, der dort die Aushärtung des Bindemittels fördert. Zudem weicht das Wasser die Fasern an der Oberfläche der Fasermatte an, so daß durch die Einwirkung der glatten Heizflächen besonders gut glatte Oberflächen bei den fertigen Faserplatten erzielt werden können.In the new process is not to be overlooked that the low Density, which is already present in the fiber mat, a heat transfer to the middle of the fiber mat during the heat treatment not exactly relieved. That's why it's new Method preferred, the fiber mat before heat treatment with To spray water or an aqueous solution. In this way can be steamed by water evaporating on the heating surfaces be directed into the interior of the fiber mat, there the Curing of the binder promotes. In addition, the water gives way to the Fibers on the surface of the fiber mat, so that through the Influence of smooth heating surfaces particularly good smooth surfaces can be achieved in the finished fiberboard.

Bis auf die Festlegung der flächenbezogenen Massenbelegung kann die Fasermatte durch die auf Abstand gesteuerten Heizflächen auch kalibriert werden.Except for the determination of the area-related mass occupancy the fiber mat through the spaced controlled heating surfaces also be calibrated.

Der vorgegebene Abstand der Heizflächen, der der Dicke der hergestellten Faserplatten entspricht, beträgt typischerweise 20 bis 300 mm. Es ist gerade im Bereich der größeren Dicken in diesem Bereich erstaunlich, daß die Faserplatten dennoch nach einem Trockenverfahren herstellbar sind.The given distance of the heating surfaces, the thickness of the is typically 20 up to 300 mm. It's just in the area of bigger thicknesses in This area amazing that the fiberboard still after can be produced by a dry process.

Besonders bevorzugt ist es bei dem neuen Verfahren, wenn das Rohdichteprofil der Faserplatten so eingestellt wird, daß sich eine Randüberhöhung der Rohdichte gegenüber der mittleren Rohdichte der Faserplatten von mindestens 60 % ergibt. Eine stärkere Randüberhöhung der Rohdichte ist Grundlage für die Ausbildung einer besonders festen geschlossenen Oberfläche der fertigen Faserplatten, die beispielsweise auch eine beachtliche Druckstabilität verglichen mit der mittleren Rohdichte der Faserplatten aufweisen kann.It is particularly preferred in the new method, if the Density profile of the fiberboard is adjusted so that an edge exaggeration of the density compared to the middle Density of the fiberboard of at least 60% results. A Stronger marginal increase in density is the basis for the Forming a particularly strong closed surface of finished fiberboard, for example, a considerable Pressure stability compared to the average density of the Can have fiberboard.

Wenn die mittlere Rohdichte der Faserplatten bei dem neuen Verfahren auf 150 bis 350 kg/m3 eingestellt wird, kann als Bindemittel ein übliches Kunstharz der Holzwerkstoffindustrie verwendet werden. Die üblichen Kunstharze der Holzwerkstoffindustrie umfassen dabei Harnstoff-Formaldehyd-, Melamin-Harnstoff-Formaldehyd-, Melamin-Harnstoff-Phenol-Formaldehyd-, Phenol-Harnstoff-Formaldehyd-, Phenol-Formaldehyd- und PMDI-Harze.If the average bulk density of the fiberboards is set to 150 to 350 kg / m 3 in the new method, a common synthetic resin of the wood-based material industry can be used as the binder. The usual synthetic resins of the wood-based materials industry include urea-formaldehyde, melamine-urea-formaldehyde, melamine-urea-phenol-formaldehyde, phenol-urea-formaldehyde, phenol-formaldehyde and PMDI resins.

Wenn die mittlere Rohdichte der Faserplatten bei dem neuen Verfahren auf 60 bis 250 kg/m3 eingestellt wird, kann als Bindemittel ein schaumbildendes Polyurethanbindemittel verwendet werden. In dem darüberliegenden Bereich der Rohdichte macht sich der Vorteil der Ausfüllung der Hohlräume in der Faserplatte zwischen den einzelnen Fasern durch den Polyurethanschaum nicht mehr in wirtschaftlich verwertbarer Weise bemerkbar. Die besonders leichten Faserplatten im Bereich unter 150 kg/m3 sind aber ohne Verwendung eines schaumbildenden Bindemittels nicht in brauchbarer Qualität herstellbar.When the average apparent density of the fiberboards is set at 60 to 250 kg / m 3 in the new method, a foaming polyurethane binder may be used as the binder. In the overlying range of bulk density, the advantage of filling the voids in the fiberboard between the individual fibers by the polyurethane foam is no longer noticeable in an economically utilizable way. The particularly light fiberboard in the range below 150 kg / m 3 but can not be produced in usable quality without the use of a foam-forming binder.

Als schaumbildendes Polyurethanbindemittel kann ein sogenanntes Einkomponentensystem zur Anwendung kommen, welches beispielsweise von der Firma Bayer entwickelt wurde und grundsätzlich verfügbar ist. Vorzugsweise wird aber ein leichter beherrschbares Zweikomponentensystem eingesetzt, wobei das schaumbildende Polyurethanbindemittel eine erste, NCO-Gruppen-aufweisende Bindemittelkomponente und eine zweite mindestens ein Polyol aufweisende Bindemittelkomponente aufweist.As foam-forming polyurethane binder may be a so-called One-component system are used, which for example was developed by the company Bayer and basically is available. Preferably, however, an easier manageable Used two-component system, wherein the foam-forming Polyurethane binders a first, having NCO groups Binder component and a second at least one polyol comprising binder component.

Dabei ist es in einer besonders bevorzugten Ausführungsform des neuen Verfahrens vorgesehen, die Fasern vor dem Aufbringen des Bindemittels in mindestens zwei Partien aufzuteilen und auf eine erste dieser Partien nur die erste, die NCO-Gruppen aufweisende Bindemittelkomponente und auf eine zweite dieser Partien nur die zweite, das Polyol aufweisende Bindemittelkomponente aufzubringen und die Partien der Fasern erst unmittelbar vor dem Formen der Fasermatte miteinander zu vermischen. Bis zum Vermischen der Partien der Fasern sind die beiden Bindemittelkomponenten so vollständig voneinander getrennt. Auch während des Vermischens der Partien der Fasern ergibt sich noch kein nennenswerter Kontakt der beiden Bindemittelkomponenten. Erst beim Formen der Fasermatte stellt sich dieser Kontakt an den Kontaktstellen der Fasern ein. Dieser Kontakt reicht aber immer noch nicht aus, um allein eine Polyurethanreaktion in nennenswertem Umfang auszulösen. Erst über sehr lange Zeiträume hinweg bzw. durch die Wärmebehandlung wird der relevante Hauptteil der Polyurethanreaktion ausgelöst, der dann zur gewünschten Bindung der Fasern in den Faserplatten führt. Dabei ist es überraschend, daß die Polyurethanreaktion letztlich trotz der mikroskopisch gesehen inhomogenen Verteilung der Bindemittelkomponenten bei der Wärmebehandlung vollständig erfolgt. Das heißt es ist keine merkliche Reaktionseinbuße dadurch festzustellen, daß beide Bindemittelkomponenten nicht auf allen Fasern vorliegen. Da gleichzeitig die Reaktivität des Bindemittels voll auf die Polyurethanreaktion innerhalb der Fasermatte konzentriert ist, kann das Bindemittel in relativ geringen Anteilen bezogen auf die Fasern und die angestrebten Festigkeiten der Faserplatten eingesetzt werden.It is in a particularly preferred embodiment of the new process, the fibers before applying the Binder divided into at least two batches and on a first of these games only the first, having the NCO groups Binder component and on a second of these parts only the second, the polyol-containing binder component to apply and the parts of the fibers only just before molding to mix the fiber mat together. Until mixing the Lots of fibers are the two binder components so completely separated from each other. Also during mixing The parts of the fibers are not yet worth mentioning Contact of the two binder components. Only when molding the Fiber mat turns this contact at the contact points of the Fibers. But this contact is still not enough to alone trigger a significant amount of polyurethane reaction. Only over very long periods of time or through the Heat treatment becomes the relevant main part of the polyurethane reaction which then causes the desired binding of the fibers in the fiberboard leads. It is surprising that the Polyurethane reaction ultimately, despite the microscopic view inhomogeneous distribution of binder components in the Heat treatment is complete. That means it is not noticeable loss of reaction as a result of both Binder components are not present on all fibers. There at the same time the reactivity of the binder fully on the Polyurethane reaction is concentrated within the fiber mat, the binder can be obtained in relatively small proportions the fibers and the desired strength of the fiberboard be used.

Bei dem neuen Verfahren kann die erste Partie grundsätzlich 10 bis 90 % und die zweite Partie entsprechend 90 bis 10 % der gesamten Fasern enthalten. Es ist aber durchaus sinnvoll, wenn die erste und die zweite Partie der Fasern ungefähr gleich groß sind, d. h. beispielsweise jeweils 40 bis 60 % der gesamten Fasern enthalten.In the new process, the first batch can basically be 10 up to 90% and the second batch corresponding to 90 to 10% of the contain entire fibers. But it makes sense if the first and second parts of the fibers are about the same size are, d. H. For example, each 40 to 60% of the total Contain fibers.

Dem steht aber nicht im Wege, daß auch noch eine dritte Partie der Fasern vor dem Vermischen einer anderen Behandlung unterworfen wird. Insbesondere kann eine dritte Partie der Fasern ohne Bindemittelkomponente belassen werden, bis sie mit den anderen Partien vermischt wird. Dieses Vorgehen ist insbesondere im Bereich sehr niedriger Bindemittelanteile interessant.But that does not stand in the way that even a third game subjecting the fibers to another treatment prior to blending becomes. In particular, a third batch of fibers be left without binder component until with the other parts is mixed. This procedure is particular interesting in the range of very low binder proportions.

Das neue Verfahren kann sowohl diskontinuierlich als auch kontinuierlich durchgeführt werden, was bevorzugt ist. Bei kontinuierlicher Verfahrensführung sind die Heizflächen typischerweise an rückwärtig beheizten metallenen Endlosbändern vorgesehen. The new process can be both discontinuous as well be carried out continuously, which is preferred. at continuous process control are the heating surfaces typically at rear heated metal endless belts intended.

Wenn das neue Verfahren unter Verwendung eines PUR-Bindemittels mit zwei Bindemittelkomponenten kontinuierlich durchgeführt wird, können die Partien der Fasern nach dem Aufbringen der Bindemittelkomponenten und vor ihrem Mischen getrennt voneinander zwischengelagert werden. Die Reaktivität der Bindemittelkomponenten nimmt bei getrennter Zwischenlagerung der Partien der Fasern auch binnen längerer Zeiträume nicht ab.If the new process using a polyurethane binder carried out continuously with two binder components After the application of the fibers, the batches of fibers can Binder components and before mixing them separately be stored by each other. The reactivity of the Binder components increases in separate storage of the Part of the fibers does not decrease even for longer periods of time.

Bei dem neuen Verfahren kann die Wärmebehandlung so vorgenommen werden, daß in der Mitte des Formkörpers eine Temperatur von nur 50 bis 100 °C erreicht wird. Das bedeutet, daß im Vergleich zu bekannten Verfahren sehr geringe Temperaturen in der Mitte des Formkörpers ausreichend sind. Diese resultieren umgekehrt in einen hohen Wirkungsgrad der bei der Wärmebehandlung eingesetzten Energie und kurze Zeiträume, die für die Wärmebehandlung benötigt werden. Die geringe Temperatur ist bei dem neuen Verfahren zumindest dann für das Aushärten des Bindemittelanteils in der Mitte des Formkörpers ausreichend, wenn hochreaktive Polyurethanbindemittel verwendet werden, deren Reaktion nicht chemisch behindert ist, um eine Vorreaktion zu unterdrücken.In the new method, the heat treatment can be made be that in the middle of the molding a temperature of only 50 to 100 ° C is reached. That means that compared to known methods very low temperatures in the middle of the Shaped body are sufficient. These result inversely in a high efficiency of the used in the heat treatment Energy and short periods of time for the heat treatment needed. The low temperature is at the new Process at least then for the curing of the binder content in the middle of the molding sufficient if highly reactive polyurethane binders are used, whose Reaction is not chemically hindered to a pre-reaction suppress.

Vorzugsweise sind die Fasern, die bei dem neuen Verfahren verarbeitet werden, Holzfasern in Form von üblichem Defibratorfaserstoff.Preferably, the fibers used in the new process be processed, wood fibers in the form of conventional Defibratorfaserstoff.

Der Bindemittelanteil kann bei dem neuen Verfahren in weiten Grenzen gewählt werden, die durch die notwendige Festigkeit der Faserplatten einerseits und die Wirtschaftlichkeit des Verfahrens angesicht hoher Bindemittelkosten andererseits gesetzt sind. Die folgenden Angaben beziehen sich auf die Verwendung eines PUR-Bindemittels.The binder content can be far in the new process Borders are selected by the necessary strength of the Fiberboard on the one hand and the economy of the Process face high binder costs on the other hand are set. The following information refers to the Use of a polyurethane binder.

In einer Ausführungsform des neuen Verfahrens wird die mittlere Rohdichte des Formkörpers auf 60 bis 250 kg pro m3 eingestellt, wobei der Bindemittelanteil des Formkörpers auf insgesamt 2,5 bis 5 Gewichts-% bezogen auf atro Holzfasern eingestellt wird. In one embodiment of the new process, the average density of the shaped body is adjusted to 60 to 250 kg per m 3 , wherein the binder content of the molding is adjusted to a total of 2.5 to 5% by weight based on atro wood fibers.

Hierdurch ergeben sich Formkörper, die zum Teil als reine Wärmedämmkörper und zu größeren Rohdichten hin auch als Wandelemente mit hoher Steifigkeit und hohem Dämmpotential verwendbar sind.This results in moldings, some of them as pure Heat insulation body and to greater densities also as Wall elements with high rigidity and high insulation potential are usable.

In einer weiteren Ausführungsform des neuen Verfahrens wird die mittlere Rohdichte des Formkörpers auf 250 bis 400 kg/m3 eingestellt, wobei der Bindemittelanteil des Formkörpers auf insgesamt 7 bis 15 Gewichts-% bezogen auf atro Holzfasern eingestellt wird. Hieraus ergeben sich beispielsweise extrem feste aber trotzdem noch sehr leichte Faserplatten mit hohem Schalldämmungspotential. Die Faserplatten sind aufgrund ihrer Festigkeit und die Feuchtebeständigkeit ihrer Verklebung auch als Baumaterial verwendbar, wobei besonders ihr immer noch relativ geringes Gewicht von Vorteil ist.In a further embodiment of the novel process, the average density of the molding is adjusted to 250 to 400 kg / m 3 , wherein the binder content of the molding is adjusted to a total of 7 to 15% by weight based on atro wood fibers. This results, for example, extremely strong but still very light fiberboard with high sound insulation potential. Due to their strength and the resistance to moisture of their bonding, the fibreboards can also be used as building materials, with their relatively low weight still being particularly advantageous.

Das neue Verfahren kann auch so durchgeführt werden, daß beim Formen der Vorform aus den Fasern ein Schichtaufbau mit unterschiedlichen Zusammensetzungen und/oder Anteilen des Bindemittels in den einzelnen Schichten eingestellt wird. So können beispielsweise die Bindemittelanteile in den Deckschichten einer Faserplatte größer sein als in der Mittelschicht, um eine besonders hohe Stabilität der Deckschichten zu erreichen. Es sind aber auch andere Schichtaufbauten zur Anpassung an bestimmte Anforderungsprofile mit dem neuen Verfahren realisierbar. Dabei versteht es sich, daß Partien von Fasern, die für unterschiedliche Schichten des Schichtaufbaus vorgesehen sind, vor dem Ausbilden der Fasermatte nicht miteinander vermischt werden, sondern nur solche Fasern, die für jeweils eine Schicht mit gleichmäßiger Zusammensetzung vorgesehen sind.The new method can also be carried out so that the Forming the preform from the fibers using a layer construction different compositions and / or proportions of Binder is set in each layer. So For example, the binder levels in the topcoats a fiberboard be larger than in the middle layer, to a particularly high stability of the outer layers too to reach. But there are also other layer structures for Adaptation to specific requirement profiles with the new procedure realizable. It is understood that lots of Fibers used for different layers of the layer structure are provided, not with each other before forming the fiber mat but only those fibers that are mixed for each provided a layer of uniform composition are.

Bei dem neuen Verfahren in den Ausführungsformen mit dem PUR-Bindemittel aus zwei Bindemittelkomponenten kann insbesondere durch Variation von Zusammensetzung und relativem Anteil der das Polyol aufweisenden Bindemittelkomponente das bekannte breite Spektrum der Eigenschaften von Polyurethanbindungen ausgenutzt werden. Dabei ist auch eine Verwendung von als Beschleuniger oder Verzögerer wirkenden Zusätzen zu einer oder beiden der Bindemittelkomponenten möglich. Ebenso können fungizide und/oder herbizide Zusätze für den herzustellenden Formkörper verwendet werden.In the new process in the embodiments with the PUR binder of two binder components may in particular by variation of composition and relative proportion of the Polyol-containing binder component known wide Spectrum of the properties of polyurethane bonds exploited become. It is also a use of as an accelerator or retarder additives to one or both of the Binder components possible. Likewise, fungicidal and / or herbicidal additives used for the shaped body to be produced become.

Die Erfindung wird im folgenden anhand von Ausführungsbeispielen näher erläutert und beschrieben. Dabei zeigt die

Figur
ein Flußdiagramm zum prinzipiellen Ablauf einer speziellen Ausführungsform des neuen Verfahrens.
The invention is explained in more detail below with reference to exemplary embodiments and described. It shows the
figure
a flowchart for the basic procedure of a specific embodiment of the new method.

Bevor anhand der Figur auf spezielle Ausführungsformen des neuen Verfahrens eingegangen werden soll, bei denen ein PUR-Bindemittel aus verschiedenen Bindemittelkomponenten zum Einsatz kommt, sollen die grundsätzlichen Ausführungsformen des neuen Verfahrens anhand verschiedener Dichtebereiche erläutert werden.Before referring to the figure on specific embodiments of the new Process is to be received, in which a PUR binder made of various binder components used comes, should the basic embodiments of the new Be explained method based on different density ranges.

Im Dichtebereich von 60 bis 150 kg/m3 ergeben sich mechanisch stabile Faserplatten unter Verwendung eines schaumbildenden Bindemittels, d. h. eines Polyurethanbindemittels, welches mindestens zwei Bindemittelkomponenten PMDI und Polyol aufweist oder bei dem es sich um ein Einkomponentensystem handelt. Derartige Faserplatten können auch als durch Fasern stabilisierter Polyurethanschaum angesehen werden. Der Bindemittelanteil atro Fasern beträgt mindestens 5 % ist damit absolut gesehen aber immer noch relativ klein.In the density range of 60 to 150 kg / m 3 , mechanically stable fiberboards result using a foam-forming binder, ie a polyurethane binder which has at least two binder components PMDI and polyol or which is a one-component system. Such fiber boards may also be considered fiber stabilized polyurethane foam. The binder content of atro fibers is at least 5%, so in absolute terms it is still relatively small.

Ab einer mittleren Rohdichte von etwa 150 kg/m3 sind weniger Hohlräume zwischen den Fasern vorhanden, so daß der Bindemittelanteil, bei Verwendung eines schaumbildenden Polyurethanbindemittels unter 5 % atro Fasern reduziert werden kann. Wenn die Stabilitäten nicht im Vordergrund stehen, können Bindemittelanteile bis hinab in den Bereich oberhalb 1 % ausreichen. Dabei verstehen sich alle Prozentangaben wie üblich als Gewichts-%-Angaben. From an average density of about 150 kg / m 3 less voids between the fibers are present, so that the binder content can be reduced when using a foam-forming polyurethane binder below 5% atro fibers. If the stabilities are not paramount, binder levels down to within 1% may be sufficient. All percentages are, as usual, weight percentages.

Ab mittleren Rohdichten um 150 bis 200 kg/m3 können auch nichtschaumbildende Bindemittel, d. h. übliche Kunstharze der Holzwerkstoffindustrie, Verwendung finden. Bei geringeren Rohdichten in diesem Bereich sollte aber der Bindemittelanteil auch für geringere Festigkeiten oberhalb 5 % gewählt werden, und für höhere Festigkeiten sind 7 bis 15 % Bindemittelanteil anzusetzen. Bevorzugt sind statt den relativ brüchig aushärtendem Harnstoff-Formaldehyd-Harzen Mischsysteme mit Zugaben von Melamin und Phenolen. Dabei müssen die üblichen Abwägungen zwischen dem Preis des Bindemittels, möglicher Formaldehydabspaltung und möglichen schädlichen Restphenolen getroffen werden.From average densities of about 150 to 200 kg / m 3 , it is also possible to use non-foam-forming binders, ie customary synthetic resins from the wood-based panel industry. With lower densities in this range, however, the binder content should also be selected for lower strengths above 5%, and for higher strengths 7 to 15% binder content should be used. Preference is given to mixing systems with additions of melamine and phenols instead of the relatively brittle hardening urea-formaldehyde resins. The usual considerations between the price of the binder, possible formaldehyde elimination and possible harmful residual phenols must be taken.

Auch im Bereich mittlerer Rohdichten bis 350 kg/m3 und darüber kann ein schaumbildendes Bindemittel zur Anwendung kommen, wobei dann auch mit relativ geringen Bindemittelanteilen hochfeste Faserplatten herstellbar sind.Also in the range average gross densities up to 350 kg / m 3 and above, a foam-forming binder can be used, in which case high-strength fiberboard can be produced even with relatively low binder levels.

Das in dem Flußdiagramm gemäß der Figur dargestellte Verfahren zur Herstellung Polyurethan-gebundener Formkörper geht von Holz 1 aus, das in üblicher Weise zerkleinert und anschließend in einem Defibrator 2 in einzelne Holzfasern 3 aufgeschlossen wird. Der Strom der Holzfasern 3 wird anschließend in einer Aufteileinrichtung 4 in zwei Partien 5 und 6 aufgeteilt, wobei die Partien 5 und 6 gleich groß sind. Auf die Holzfasern 3 der Partie 5 wird in einer Aufbringeinrichtung 7 eine NCO-Gruppen enthaltende Bindemittelkomponente 8, ein sogenanntes PMDI, aufgebracht. Die Formulierung des PMDI's 8 entspricht einer solchen, wie sie in der Holzwerkstoffindustrie üblicherweise als alleiniges Bindemittel verwendet wird. Auf die Holzfasern 3 der Partie 6 wird in einer Aufbringeinrichtung 9 eine mindestens ein Polyol aufweisende Bindemittelkomponente 10 aufgebracht. Hier handelt es sich vorzugsweise um eine Mischung eines kurzkettigen mit einem langkettigen Polyol. Beispielsweise ist eine Mischung aus einem Teil Diethylenglycol und einem Teil Polyetheralkohol der Molmasse 1000 einsetzbar. Beide Aufbringeinrichtungen 7 und 9 arbeiten nach dem Prinzip, daß das PMDI 8 bzw. das Polyol 10 auf die Holzfasern 3 aufgesprüht wird. Anschließend werden die Partien 5 und 6 bei Bedarf in getrennten Zwischenspeichern 11 und 12 zwischengelagert. Dabei kann es sich um übliche Holzfaserbunker handeln. Eine Zwischenlagerung ist dabei grundsätzlich optional und muß nicht zwingend erfolgen. Sie erlaubt es jedoch, die weiteren Verfahrensschritte von den bis hierher beschriebenen Verfahrensschritten zu entkoppeln, um letztlich einen optimalen Wirkungsgrad des Herstellverfahrens zu erreichen. In einer Mischeinrichtung 13 werden die Holzfasern 3 der Partien 5 und 6 miteinander vermischt. Bei geeigneter Zusammenführung der Stoffströme der Partien 5 und 6 kann die erforderliche Durchmischung auch durch Walzen eines Streukopfs einer Streueinrichtung 14 erfolgen. Aus den Holzfasern 3 beider Partien 5 und 6 wird in der Streueinrichtung 14 eine Fasermatte 15 gestreut, die eine Vorform der hier hergestellten Faserplatten 18 darstellt. Die Fasermatte 15 wird in einer Kalibriereinrichtung 16 kalibriert, bei der es sich um eine kaltvorverdichtende Vorpresse handelt. Anschließend erfolgt in einer Heißpresse 17 eine Wärmebehandlung, aus der die gewünschte Faserplatte 18 resultiert. Dabei ist die Heißpresse 17 nicht so zu verstehen, daß die Fasermatte 15 unbedingt unter Aufbringung von Druck zusammengepreßt wird. Vielmehr sind die Platten der Heißpresse 17 distanzgesteuert, um auch ohne bleibenden Gegendruck der Fasermatte 15 zu Faserplatten 18 mit definierter Dicke zu kommen. Das neue Verfahren kann sowohl mit einer Bandpresse als Heißpresse 17 als auch mit einer diskontinuierlich arbeitenden Heißpresse durchgeführt werden. Es kann vorteilhaft sein, anstelle von oder alternativ zu heißen Kontaktflächen auch eine Heißlufterwärmung oder eine Hochfrequenzerwärmung der kalibrierten Fasermatte 15 vorzusehen. Bei einer Erwärmung über heiße Kontaktflächen ist es vorteilhaft, die Oberflächen der Fasermatte 15 mit Wasser zu besprühen, so daß das an den heißen Kontaktflächen verdampfende Wasser Wärme auch in das Innere der Fasermatte 15 überträgt. Dies ist besonders vorteilhaft, wenn die Fasermatte 15 sehr dick ist, d. h. mehr als 40 mm dick.The method illustrated in the flow chart of the figure for the production of polyurethane-bound molded body goes from wood 1, which is comminuted in the usual way and then in a defibrator 2 in individual wood fibers 3 is digested. The stream of wood fibers 3 is then in a Dividing device 4 divided into two parts 5 and 6, wherein the games 5 and 6 are the same size. On the wood fibers 3 of the Lot 5 becomes in an applicator 7 an NCO groups containing binder component 8, a so-called PMDI, applied. The formulation of PMDI 8 corresponds to one such as those commonly used in the wood-based panel industry sole binder is used. On the wood fibers 3 of the Lot 6 is in an applicator 9 one at least one Polyol-containing binder component 10 applied. Here it is preferably a mixture of short chain with a long-chain polyol. For example, a mixture one part of diethylene glycol and one part of polyether alcohol the molecular weight 1000 can be used. Both application devices 7 and 9 work on the principle that the PMDI 8 and the polyol 10th is sprayed onto the wood fibers 3. Subsequently, the Lots 5 and 6 if necessary in separate buffers 11 and 12 intermediately stored. These may be conventional wood fiber bunkers act. An intermediate storage is basically optional and does not have to be mandatory. she allows it, however, the further process steps from here to here Decouple described method steps to ultimately to achieve optimum efficiency of the manufacturing process. In a mixing device 13, the wood fibers 3 of the Batches 5 and 6 mixed together. With a suitable combination the streams of lots 5 and 6 may be the required mixing also by rolling a scattering head a scattering device 14 done. From the wood fibers 3 both Batches 5 and 6 becomes a fiber mat in the spreader 14 15, which is a preform of fiberboard produced here 18 represents. The fiber mat 15 is in a calibration device 16 calibrated, which is a cold pre-compression Prepress is. Subsequently, in a Hot press 17 a heat treatment from which the desired Fiberboard 18 results. The hot press 17 is not so to understand that the fiber mat 15 under application compressed by pressure. Rather, the plates are the Hot press 17 distance-controlled, even without a constant back pressure the fiber mat 15 to fiber plates 18 with a defined thickness get. The new process can be done with both a belt press as a hot press 17 as well as with a discontinuous working Hot press to be performed. It can be beneficial instead of or alternatively to hot contact surfaces also a Hot air heating or high frequency heating of the calibrated Fiber mat 15 provide. When warming over hot contact surfaces, it is advantageous to the surfaces of Sprinkle fiber mat 15 with water, so that on the hot Contact surfaces evaporating water heat also into the interior of the Fiber mat 15 transfers. This is especially beneficial if the fiber mat 15 is very thick, d. H. more than 40 mm thick.

Im folgenden werden jetzt einzelne konkrete Ausführungsbeispiele für die Herstellung von Faserplatten 18 nach dem in der Figur skizzierten Verfahren beschrieben. Das neue Verfahren ist grundsätzlich aber auch zur Herstellung von Spanplatten und anderen Platten aus anderen Lignocellulose-haltigen oder anderen zumindest OH-Gruppen aufweisenden Partikeln anwendbar. Diese müssen nicht tatsächlich aus Holz gewonnen sein. Insbesondere können auch andere pflanzliche Grundsubstanzen Verwendung finden. Darüberhinaus ist es möglich, auch Substanzen nicht pflanzlichen Ursprungs zuzuschlagen, sofern sie bei der Polyurethanbindung mit eingebunden werden können.In the following, individual concrete embodiments will now be described for the production of fiberboard 18 after that in the figure outlined method described. The new procedure is but in principle also for the production of chipboard and other plates from other lignocellulosic or other applicable at least OH-containing particles. These do not really have to be made of wood. Especially You can also use other basic vegetable substances Find. Moreover, it is not possible, even substances of plant origin, provided they are in the polyurethane bond can be integrated with.

Den folgenden Beispielen ist gemeinsam, daß das verwendete PMDI, d. h. die NCO-Gruppen aufweisende Bindemittelkomponente, eine Zusammensetzung aufwies, wie sie in der Holzwerkstoffindustrie üblich ist. Die zweite, Polyol aufweisende Bindemittelkomponente war die ebenfalls bereits oben angesprochene Mischung von einem Teil Diethylenglycol und einem Teil Polyetheralkohol der Molmasse 1000. Als Mischeinrichtung 13 kam eine einfache Drehtrommel zur Anwendung. Die Mischzeit der beiden Partien 5 und 6 betrug dabei 10 Sekunden. Die Temperatur der Kontaktflächen der Heißpresse 17 wurde auf 170 °C eingestellt. Alle %-Angaben sind in Gewichts-%.The following examples have in common that the PMDI used, d. H. the NCO group-containing binder component, a Had composition, as used in the wood-based panel industry is common. The second polyol component binder component was the already mentioned above mixture of one Part of diethylene glycol and one part of polyether alcohol of molecular weight 1000. As a mixing device 13 came a simple rotary drum for use. The mixing time of the two games 5 and 6 was 10 seconds. The temperature of the contact surfaces of Hot press 17 was set at 170 ° C. All% information is in weight%.

Beispiel 1:Example 1:

Das PMDI 8 wurde in einem Anteil von 2,5 % und das Polyol 10 in einem Anteil von 1 % bezogen auf atro Holzfasern 3 eingesetzt. Nach 240 sek. Verweildauer der Fasermatte 15 in der Heißpresse 17 wurde eine 100 mm dicke Faserplatte 18 entnommen. Die mittlere Rohdichte dieser Faserplatte 18 betrug 80 kg/m3. Trotz der sehr geringen Verdichtung der Holzfasern in dieser Faserplatte war die Faserplatte für einen Dämmstoff vollkommen ausreichend formstabil und handhabbar.The PMDI 8 was used in a proportion of 2.5% and the polyol 10 in a proportion of 1% based on atro wood fibers 3. After 240 sec. Dwell time of the fiber mat 15 in the hot press 17, a 100 mm thick fiber plate 18 was removed. The average bulk density of this fiberboard 18 was 80 kg / m 3 . Despite the very low compression of the wood fibers in this fiber board, the fiber board for an insulating material was perfectly stable and manageable.

Beispiel 2:Example 2:

Die Bindemittelanteile entsprachen dem Beispiel 1. Nach 300 sek. Verweildauer der Fasermatte 15 in der Heißpresse 17 wurde eine 50 mm dicke Faserplatte 18 entnommen. Die mittlere Rohdichte betrug 170 kg/m3. Die Biegefestigkeit der Faserplatte 18 lag bei 0,3 N/mm2. Die Druckspannung bei 10 % Stauchung lag bei 0,18 N/m2.The binder proportions corresponded to Example 1. After 300 sec. Dwell time of the fiber mat 15 in the hot press 17, a 50 mm thick fiber plate 18 was removed. The average bulk density was 170 kg / m 3 . The flexural strength of the fiberboard 18 was 0.3 N / mm 2 . The compressive stress at 10% compression was 0.18 N / m 2 .

Die obigen Festigkeitswerte lassen eindeutig darauf schließen, daß die Reaktivität beider Bindemittelkomponenten 8 und 10 für die Bindung der Holzfasern in der Faserplatte 18 voll ausnutzbar ist. Gleichzeitig ist festzustellen, daß trotz der Einbringung der beiden Bindemittelkomponenten 8 und 10 über unterschiedliche Partien 5 und 6 der Holzfasern 3 die Polyurethanreaktion bei der erhöhten Temperatur in der Heißpresse 17 offensichtlich nicht behindert wird, was als durchaus überraschend angesehen werden muß. The above strength values clearly suggest that that the reactivity of both binder components 8 and 10 for the binding of the wood fibers in the fiberboard 18 fully exploitable is. At the same time it should be noted that despite the contribution the two binder components 8 and 10 via different Lots 5 and 6 of wood fibers 3 the polyurethane reaction in the increased temperature in the hot press 17 obviously not is hindered, which is considered quite surprising got to.

BEZUGSZEICHENLISTELIST OF REFERENCE NUMBERS

1 -1 -
HolzWood
2 -2 -
Defibratordefibrator
3 -3 -
Fasernfibers
4 -4 -
AufteileinrichtungA distributor
5 -5 -
Partiegame
6 -6 -
Partiegame
7 -7 -
Aufbringeinrichtungapplicator
8 -8th -
Bindemittelkomponente/PMDIBinder component / PMDI
9 -9 -
Aufbringeinrichtungapplicator
10 -10 -
Bindemittelkomponente/PolyolBinder component / polyol
11 -11 -
Zwischenspeichercache
12 -12 -
Zwischenspeichercache
13 -13 -
Mischeinrichtungmixing device
14 -14 -
Streueinrichtungscattering device
15 -15 -
Fasermattefiber mat
16 -16 -
Kalibriereinrichtungcalibration
17 -17 -
Heißpressehot press
18 -18 -
Faserplattefibreboard

Claims (20)

  1. A method of producing light weight fibre boards having an average bulk density of less than 400 kg/m3 based on lingo cellulose containing fibres and binder, the binder being applied to the fibres and the fibres being then formed into a fibre mat which is calibrated and subjected to a heat treatment for curing the binder, characterized in that a moisture content of the fibres (3) is adjusted in such a way that it is below 20 % during calibrating the fibre mat (15) and during the heat treatment, and that the fibre mat (15) is contacted on both sides with smoothly closed heating surfaces for heat transfer during the heat treatment, the heating surfaces opposing each other being distance controlled to keep a predetermined distance, and the bulk density profile of the fibre boards (18) being adjusted in such a way that an increase of the bulk density at the boundary of the bulk density profile amounts to at least 20 % with regard to the average bulk density of the fibre boards (18).
  2. The method of claim 1, characterized in that water or an aqueous solution is sprayed onto the fibre mat (15) prior to the heat treatment.
  3. The method of claim 1 or 2, characterized in that the predetermined distance of the heating surfaces is between 20 and 300 mm.
  4. The method according to any of the claims 1 to 3, characterized in that the bulk density profile of the fibre boards (18) is adjusted in such a way that an increase of the bulk density at the boundary of the bulk density profile amounts to at least 60 % with regard to the average bulk density of the fibre boards.
  5. The method according to any of the claims 1 to 4, characterized in that the average bulk density of the fibre boards (18) is adjusted to 150 to 350 kg/m3, the binder (8, 10) being an usual artificial resin used in wood particle material industry and being selected from the group including UF, MUF, MUPF, PUF, PF and PMDI resins.
  6. The method according to any of the claims 1 to 4, characterized in that the average bulk density of the fibre boards (18) is adjusted to 60 to 250 kg/m3, a foam forming PUR binder being used as the binder (8, 10).
  7. The method of claim 6, characterized in that the foam forming PUR binder comprises a first binder component (8) having NCO groups and a second binder component (9) comprising at least one polyol.
  8. The method of claim 7, characterized in that the fibres are divided up into at least two parts (5, 6) prior to applying the binder (8, 9), that only the first binder component (8) comprising the NCO groups is applied to the first (5) of these parts, and that only the second binder component (9) comprising the polyol is applied to the second (6) of these parts, and that the parts (5, 6) of the fibres (3) are mixed prior to forming the fibre mat (15).
  9. The method of claim 8, characterized in that the first part (5) comprises 10 to 90 %, and the second part (6) comprises 90 to 10 % of the total fibres (3).
  10. The method of claim 9, characterized in that the first part (5) comprises 40 to 60 %, and the second part (6) comprises 60 to 40 % of the total fibres (3).
  11. The method according to any of the claims 8 to 10, characterized in that no binder component is applied to a third part of the fibres (3) prior to mixing.
  12. The method according to any of the claims 1 to 11, characterized in that the method is carried out continuously.
  13. The method according to any of the claims 1 to 12, characterized in that the heat treatment is carried out until a temperature of 50 to 100 °C is reached in the middle of the fibre mat (15).
  14. The method of any of the claims 1 to 3, characterized in that, in forming the fibre mat (15) of the fibres (3), a layer arrangement with different compositions and/or concentrations of the binder within the single layers is formed.
  15. A light weight fibre board having an average bulk density of less than 400 kg/m3 based on lingo cellulose containing fibres and binder, characterized in that the fibre board (18), on both sides, has smoothly closed surfaces and an increase of the bulk density at the boundary of its bulk density profile of at least 20 % with regard to its average bulk density.
  16. Fibre board according to claim 15, characterized in that the fibre board (18) has a thickness between 20 and 300 mm.
  17. Fibre board according to claim 15 of 16, characterized in that the increase of the bulk density at the boundary of the bulk density profile amounts to at least 60 % with regard to its average bulk density.
  18. The fibre board according to any of the claims 15 to 17, characterized in that the average bulk density of the fibre board (18) is between 150 and 350 kg/m3, the binder being a usual artificial resin of wood particle material industry selected from a group including UF, MUF, LUPF, PUF, PF, and PMDI resins.
  19. The fibre board according to any of the claims 15 to 17, characterized in that the average bulk density of the fibre board (18) is between 60 and 250 kg/m3, the binder being a foam forming PUR binder.
  20. Fibre board according to any of the claims 15 to 19, characterized in that the fibre board (18) comprises a layer arrangement with different compositions and/or concentrations of the binder within the single layers.
EP00124199A 1999-12-24 2000-11-08 Process for producing a light weight fibre board with a closed surface Expired - Lifetime EP1110687B2 (en)

Applications Claiming Priority (2)

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DE19963096 1999-12-24
DE19963096A DE19963096C1 (en) 1999-12-24 1999-12-24 Polyurethane-bound molding, e.g. chipboard or fiberboard for insulation or wallboard, comprises applying isocyanate and polyol to separate batches of lignocellulose particles, mixing, preforming, calibration and heating

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EP1110687B1 true EP1110687B1 (en) 2005-12-21
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DE102010056491A1 (en) 2009-12-23 2011-07-21 Technische Universität Dresden, 01069 Preparing a molded body, comprises crushing maritime plant material from saline environment to particles, mixing particles with binders and/or aggregates, compressing the mixture into molded body and curing binder under heat
EP2786849A1 (en) 2013-04-02 2014-10-08 HOMATHERM GmbH Method for producing a multi-layered fibreboard panel, and a multi-layered fibreboard panel
US10076852B2 (en) 2016-07-21 2018-09-18 Gce deutschland gmbh Method for manufacturing a fibreboard

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DE202006009318U1 (en) * 2006-05-08 2007-09-20 Dammers, Dirk Plate, in particular panel for covering walls or ceilings or as a floor covering
DE102007019416A1 (en) * 2006-07-19 2008-01-24 Pfleiderer Holzwerkstoffe Gmbh & Co. Kg Production of base material for light-weight chipboard or fibre-board, involves mixing cellulose-containing powder, e.g. corn flour, with a hardener such as poly-isocyanate and then foaming and hardening the mixture
DE102007025801A1 (en) 2007-06-02 2008-12-04 Glunz Ag Process for the preparation of a light flexible molded article based on lignocellulose-containing fibers
PT2062709E (en) 2007-11-23 2012-08-27 Glunz Ag Boards made from wood fibres using a bonding agent
DE102014119242A1 (en) 2014-12-19 2016-06-23 Dieffenbacher GmbH Maschinen- und Anlagenbau Insulating and / or soundproofing board, their use and a method for the production of insulating and / or soundproofing panels
DE202014106187U1 (en) 2014-12-19 2016-02-22 Dieffenbacher GmbH Maschinen- und Anlagenbau Insulation and / or sound insulation board
DE202017106335U1 (en) 2017-10-19 2017-11-17 Gce deutschland gmbh Wave fiber board in the wet and semi-dry process

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FR1103226A (en) * 1954-06-28 1955-10-31 Rougier & Fils Sa Chipboard particle boards
DE2538999C3 (en) * 1975-09-02 1981-10-22 Lignotock Verfahrenstechnik Gmbh, 1000 Berlin Binder component for polyurethane binders
US4175148A (en) * 1976-11-05 1979-11-20 Masonite Corporation Product containing high density skins on a low density core and method of manufacturing same
SE504637C2 (en) * 1995-07-27 1997-03-24 Sunds Defibrator Ind Ab Process for making lignocellulosic discs
DE19604575A1 (en) * 1996-02-08 1997-08-28 Glunz Ag Process for the production of chipboard or fiberboard
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Publication number Priority date Publication date Assignee Title
DE102010056491A1 (en) 2009-12-23 2011-07-21 Technische Universität Dresden, 01069 Preparing a molded body, comprises crushing maritime plant material from saline environment to particles, mixing particles with binders and/or aggregates, compressing the mixture into molded body and curing binder under heat
EP2786849A1 (en) 2013-04-02 2014-10-08 HOMATHERM GmbH Method for producing a multi-layered fibreboard panel, and a multi-layered fibreboard panel
US10076852B2 (en) 2016-07-21 2018-09-18 Gce deutschland gmbh Method for manufacturing a fibreboard
US10647021B2 (en) 2016-07-21 2020-05-12 Homann Holzwerkstoffe GmbH Fibreboard

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EP1110687B2 (en) 2010-02-03
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DE50011903D1 (en) 2006-01-26
CY1104997T1 (en) 2009-11-04
ATE313421T1 (en) 2006-01-15

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