EP2660408B1 - Zigzag wooden elements comprising a core layer and multiple layer composite comprising the core layer - Google Patents

Description

The present invention relates to a core layer, which has zig-zag-shaped wooden elements, which is suitable for producing a multi-layer composite or in a multi-layer composite, preferably for producing a lightweight board, as well as a multi-layer composite, which has the core layer. The invention further relates to methods for producing the core layer and the multi-layer composite.

It is known to use composite materials for the production of multilayer composites, which have a relatively high mechanical stability compared to their weight. Such multilayer composites are used for example in the form of lightweight panels.

CH 254025 relates to a multi-layer composite comprising two cover plates and a core layer therebetween, wherein the core layer comprises at least one layer of folded veneer. The veneer is folded at an angle to the grain of the grain in the wood.

DE 42 01 201 relates to semi-finished or finished product made of wood, which are made of platelet-shaped elements. The plate-shaped elements may be zigzag-shaped. They can exist in random distribution along with surface elements. The core layer off DE 42 01 201 discloses all the technical features of the introductory part of the first claim. DE 10 2008 022 806 relates to a lightweight board with a wavy wood veneer layer. The waves may be zigzag-shaped.

Common to these multilayer composites is that the core layer has a loosened structure. Upon application of force perpendicular to the surface of the multi-layer composite, this has a damping effect, since the core layer can be at least partially compressed. A disadvantage of these loosened core layers is that they may have a low homogeneity, which is caused by relatively large voids in the core layer. Then, when introducing fasteners, such as nails, furniture connectors or screws, they may encounter voids in the loosened core layers. This can result in limited stability of the fastener in the multi-layer composite. This in turn can lead to the fact that the stability of the multi-layer composite on a support, for example on a wall, can be impaired if it is to be fastened with the aid of nails or screws to the wall. In addition, the production of large-sized core layers requires correspondingly large veneer pieces in high quality.

It is an object of the present invention to provide a core layer and a multi-layer composite containing the core layer, which has improved stability with respect to fastening with nails, furniture connectors or screws or equivalent fastening means to a support, for example a wall.

This object is achieved according to the invention with a core layer which is suitable for a multi-layer composite which has at least one cover layer and the core layer, wherein the cover layer is arranged such that it at least partially covers the core layer and is in firm connection therewith, and the multi-layer composite comprising the core layer, wherein the core layer comprises wood elements having portions arranged in a zigzag shape as defined in claim 1.

First aspect of the invention Inventive core layer comprising zigzag-shaped elements made of wood

In a first aspect , the invention relates to a core layer which is suitable for a multilayer composite which has at least one cover layer and a core layer, wherein the cover layer is disposed so as to at least partially cover and be in firm connection with the core layer, the core layer comprising elements of wood having platelet-shaped portions arranged in a zigzag pattern, a zig portion of one Elements with an adjacent zack portion of the element form a common edge between them, such that the element is formed zigzag, and wherein elements in the core layer are arranged so that two such edges of two elements, the same or different may intersect each other at an angle other than zero, the two elements being fixedly connected together at the point of intersection, as defined in claim 1.

As used in this disclosure, the term "core layer suitable for a multi-layer composite" means a core layer which is suitable for producing a multi-layer composite or which may be present in a multi-layer composite.

The term "core layer" as used herein means a layer having a loosened structure, that is, having voids. According to the invention, the core layer comprises elements made of wood, which have platelet-shaped regions. These areas are arranged zig-zag in the element, wherein a zick portion of an element with an adjacent zack portion of the element form a common edge between them, such that the wood element is zigzag-shaped. The term "zig-zag shaped" is used synonymously with the term "zig-zag shaped". The zig-zag shaped elements are arranged in the core layer such that two such edges of two elements intersect at an angle other than zero. At the intersection of the edges, the two elements are firmly connected. A suitable bonding agent is preferably an adhesive. Suitable adhesives are known in the art.

The term "overcoat" as used herein means a layer of material which preferably serves as a support for the core layer. According to the invention, the cover layer is arranged such that it at least partially covers the core layer and is in firm connection therewith. The core layer may also be at least partially covered by at least two cover layers and in firm connection therewith stand. The core layer is then preferably located between the two cover layers. The cover layer may be made of wood or have wood. Other materials such as sheets or plastics are also usable.

The term "at least partially covered," as used herein, includes that the cover layer can also completely cover or cover the core layer.

The term "multi-layer composite" as used herein means a composite of at least one core layer and at least one cover layer.

The term "angle other than zero" as used herein includes the angle being neither 180 ° nor 360 °.

The term "element" as used herein means a component of the core layer or the multilayer composite.

The term "platelet-shaped regions " as used herein includes regions formed in the form of surfaces. The surfaces may be even or uneven, preferably then wavy.

As used herein, the term " wooden elements having platelet -shaped portions arranged in a zigzag shape" as used herein includes a platelet-shaped wooden member formed to have a zig-zag shape, such as Platelet is folded around an edge. Such a chip may also be folded twice, such that a zigging region is followed by a zigzag region, which in turn is followed by a zick region. Such a chip may also be folded three times such that a zigging region is followed by a zigzagging region followed by a zigging region followed by a zigzagged region; etc. Preferably, edges formed by zig-zag areas in a wood element are aligned parallel to each other.

The terms "zick area" and "zigzag area" are used interchangeably. Both the zig-zag and the zigzag area are platelet-shaped.

Accordingly, in one embodiment, the invention also relates to a core layer in which wooden elements comprise repeating units of platelet-shaped zig-zags which adjoin one another, the common edges formed between the regions preferably being parallel to each other. Such an arrangement of zig-zag areas with the element zigzag-shaped or formed.

The term "edge" as used herein includes terms such as "transitional area between a zig-zag and the adjacent zag area" . This transition region can be an edge that is sharp. The term also includes an edge configured as a curved surface. In this embodiment, the zig-zag-shaped wooden element may also have a wavy course. Thus , as used herein, the term "edge" includes a sharp edge in the form of a line, as well as a wavy or wavy edge in the form of a curved plane, or a curved area between a zig area and a zigzag area. In this embodiment, the zig-zag areas have a wave-shaped structure, ie a wave trough is followed by a wave crest and vice versa.

Such edges can be created by folding a platelet-shaped element of wood. Preferably, then the plate-shaped element is designed as a veneer.

Suitable devices for folding are known in the art. Preferably, a plate-like wooden element can be passed through a high-speed pair of profile rollers, as in DE 42 01 201 described. Preferably, the folding takes place substantially transversely to the wood fiber direction. In one embodiment, the previously plasticized by the action of moisture and heat wood structure is kinked, that is preferably designed hinged to the respective folding edge by local compression of the wood fibers, without the cohesion of the wood part is weakened. The folding can be carried out in such a way that folding back the zigzag-shaped regions in the zig-zag-shaped (shaped) element into the starting position can be at least largely avoided.

In another embodiment, the edge is made by cutting. In one embodiment, wood is cut by means of a suitable knife or blade which is profiled in a zig-zag fashion. Devices and methods are known in the art.

In one embodiment, the folding or cutting is performed so that the length of the fibers in the resulting wood element is at least twice as long as the thickness of a zig-shaped or zigzagged region. The term "thickness" as used herein means the smallest distance between two surfaces of a zigzag region. These surfaces are due to the thickness of the platelet-shaped zick or. Zack areas spaced from each other.

In one embodiment, the thickness of the plate-like element is in the range of 0.2 mm to 2 mm.

The height of the zig-zag-shaped wooden elements is typically in the range of 0.8 mm to 8 mm. The term "height" is defined as the shortest distance between two imaginary planes, between which the zig-zag-shaped wooden element can be arranged, such that the edges, which are between zig-areas and zag-shaped areas of the zigzag formed wood element are formed to lie within one of these levels.

In one embodiment, the thickness of the wood element is in the range of 0.2 mm to 2 mm and the height of the zigzag wood element is in the range of 0.8 mm to 8 mm.

In one embodiment, the thickness of the zig-zag-shaped wooden element is at most one tenth of the thickness of the core layer. This ensures sufficient homogeneity of the core layer.

The dimensions of the zig-zag-shaped wooden elements with respect to width and length may vary. Preferred ranges are selected from a range of 2 to 20 cm.

The zig-zag formed or formed elements obtained by cutting or folding may be further shredded if desired. Suitable cutting devices are known in the art.

Preferably, the edge or edges formed by the zigzag and zigzag region or by the zigzag and zigzag regions do not extend or run parallel to the preferred direction of the fibers.

In one embodiment, the fibers in two different wood elements have the same preferred direction.

In another embodiment, the fibers in two different wood elements have different preferred directions.

In one embodiment, the edge formed between a zigging region and a zigzag region of the plate-like wood element does not run parallel to the grain of the wood element.

Preferably, the edge formed between a zig area and a zigzag portion of the plate-like wood element is perpendicular to the fiber direction of the wood element.

Accordingly, this embodiment of the core layer is also characterized in that one or more of said edges extends or extend perpendicular to the preferred direction of the fibers of the plate-shaped wooden element.

This also preferably means that, in one embodiment, the direction of the fibers in the wood element extends in the direction of the zigzag-shaped adjoining platelet-shaped regions and perpendicular to their common edges.

The term "perpendicular to the fiber direction" means that a deviation in an angle of about up to 30 ° is possible.

In one embodiment, the core layer according to the invention comprises first plate-shaped wooden elements with zig-zag-shaped regions and second wooden elements with zigzag-shaped regions, wherein the first and second zigzag-shaped wooden elements may be the same or different from each other. In one embodiment, the first and second wood elements differ in their dimensions or the type of wood used. It is preferred that the wood fibers extend in said first and second elements in the same preferred direction.

Generally, more than 50% of the wood elements in the core layer are integral with each other, with a zick portion of an element having an adjacent zag portion of the element forming a common edge therebetween, and elements in the core layer are arranged such that two such edges of two different elements intersect at an angle which is different from zero, wherein the two elements are fixedly connected to each other at the crossover point. The wood elements are preferably present in the core layer in a random distribution.

Preferably, more than 60%, or more than 70%, or more than 80%, or more than 90% or even 100% of the wood elements in the core layer are arranged or randomly distributed so that they are firmly joined together. Preferably, 100% of the wood elements are arranged or randomly distributed so that they are firmly connected. In this embodiment, the core layer according to the invention has a higher mechanical stability compared to a core layer in which not all wood elements are firmly connected to each other.

It is possible that in the core layer according to the invention, regions other than the said edges of the plate-like wood elements having zigzag-shaped regions also cross over one another. For example, zigzones may intersect with zigzones of other wooden elements such that they do not intersect or overlap edges but surfaces of the regions, or said edges may cross or overlap surfaces of the zig regions.

In one embodiment, the core layer has planar elements in addition to the zig-zag-shaped wooden elements. The term "even" includes terms such as "planar" or "just formed or formed" or "planar formed or formed". These planar elements can be selected from: wood, paper, metal, plastic, and two or more of them. These flat elements can be glued to said edges of the plate-like wooden elements, which have zig-zag arranged areas. When a portion of said zigzag-shaped wooden members is adhered to said planar members, the inner cohesion of the core layer can be further improved.

In one embodiment, the zig-zag shaped wooden elements are made of veneer or Oriented Strand Board (OSB) chips. In one embodiment, the veneer is provided in the form of a sheet or in the form of strips. In one embodiment, the OSB chips are provided in the form of flakes having elongated and narrow strands.

Second aspect of the invention Process for producing a core layer comprising zig-zag-shaped elements made of wood

According to a second aspect , the invention relates to a method for producing a core layer comprising plate-like elements made of wood, which have areas which are arranged in a zigzag, wherein a zig-shaped area of an element with an adjacent serrated area of the element a form common edge between them, such that the element is zigzag-shaped or formed. The elements are arranged in the core layer such that two such edges of two elements, which may be the same or different, cross each other at an angle other than zero, as defined in claim 1.

• mit einem angrenzenden zack-förmigen Bereich des Elements eine gemeinsame Kante zwischen sich ausbilden;
  • (ii) Anordnen der Elemente aus Stufe (i) derart, dass zwei derartige Kanten zweier Elemente sich in einem Winkel überkreuzen, der verschieden von Null ist;
  • (iii) Festes Verbinden der Kanten aus Stufe (ii).

In one embodiment, the process comprises at least stages (i) and (ii):

• forming a common edge therebetween with an adjacent serrated portion of the element;
  • (ii) arranging the elements of step (i) such that two such edges of two elements intersect at an angle other than zero;
  • (iii) firmly joining the edges of step (ii).

The firm connection preferably takes place by means of an adhesive.

In a further embodiment, at the point of intersection of the edges, the two elements, which may be the same or different, are fixedly connected to each other by planar elements selected from: wood, paper, metal, plastic, and two or more thereof, the plane elements having the edges in turn are connected by a suitable connecting means such as preferably an adhesive.

In one embodiment, the placement of the elements in step (ii) can be accomplished by aligning the wooden elements, which can be done either by hand or by machine.

The solid compounding in the step (iii) can be facilitated by applying pressure which is preferably in a range of 0.02 MPa to 1.5 MPa, more preferably in a range of 0.01 to 1.0 MPa.

Each of steps (i) to (iii) may be carried out in the presence of a topcoat. Preferably, the method is then carried out so that the provided with an adhesive wood elements on the cover layer according to step (i) presented and aligned on this according to step (ii).

Preferably, this arrangement is then covered by a further cover layer and pressed. This results in a multi-layer composite comprising two outer layers and a core layer located therebetween.

Preferably, the core layer according to the first aspect or made by the method of the second aspect is planar.

Third aspect of the invention Multi-layer composite at least comprising a cover layer and a core layer

A third aspect of the invention relates to a multilayer composite comprising at least a cover layer and a core layer according to the invention, wherein the cover layer is arranged such that it at least partially covers and is in firm connection with the core layer, wherein the core layer comprises a core layer according to the invention according to the first aspect of the present invention Invention and the embodiments described therein, or a core layer is made according to the second aspect and the embodiments described therein.

The covering layer used in the multilayer composites of the invention may comprise a material selected from the group consisting of veneer, wood board, chipboard, fiberboard, plywood board, plastic board, plasterboard, sheet, fiber cement board, and two or more thereof.

Preferably, the at least one cover layer is flat, i. planar.

Preferably, the at least one cover layer has a square or rectangular shape.

The dimensions of the cover layer are not limited. Preferably, the width and the length of the at least one cover layer are each in the range of 0.50 m to 5 m, more preferably in the range of 1 to 3 m.

1. (i) Vorlegen plättchenförmiger Elemente aus Holz, welche Bereiche aufweisen, die zick-zack-förmig angeordnet sind, wobei ein zick-förmiger Bereich eines Elements mit einem angrenzenden zack-förmigen Bereich des Elements eine gemeinsame Kante zwischen sich ausbilden;
2. (ii) Anordnen der Elemente aus Stufe (i) derart, dass zwei derartige Kanten zweier Elemente sich in einem Winkel überkreuzen, der verschieden von Null ist;
3. (iii) Festes Verbinden der Kanten der Elemente aus Stufe (ii);

wobei in Stufe (ii) das Anordnen auf einer Deckschicht erfolgt, und in Stufe (iii) die Elemente auch mit der Deckschicht fest verbunden werden, vorzugsweise mittels eines Klebers.A method for producing a multilayer composite according to the invention has already been described above in connection with the production of the core layer. The process then has at least stages (i) to (iii):

1. (I) presenting platelet-shaped elements made of wood, which have areas which are arranged in a zig-zag, wherein a zig-shaped portion of an element forming a common edge therebetween with an adjacent serrated portion of the element;
2. (ii) arranging the elements of step (i) such that two such edges of two elements intersect at an angle other than zero;
3. (iii) firmly joining the edges of the elements of step (ii);

wherein in step (ii) the placing takes place on a cover layer, and in step (iii) the elements are also firmly connected to the cover layer, preferably by means of an adhesive.

If desired, the side of the core layer which does not yet have a cover layer can then be provided with a cover layer, preferably by bonding to the cover layer.

Fourth aspect of the invention Use of the core layer according to the invention and of the multilayer composite according to the invention

According to a fourth aspect, the invention further relates to the use of the multilayer composite according to the invention or the core layer according to the invention. Preferably, the multilayer composite according to the invention or the core layer according to the invention can be used in applications which allow a high mechanical stress at a relatively low weight, and / or which require a high damping capacity. In one embodiment, the multi-layer composite or core layer is used in furniture manufacturing, for shelves, for packaging for transport, for interior fittings, in doors and gates, in or as chairs, as well as in vehicle and shipbuilding. For this purpose, the multi-layer composite or the core layer can be processed by cutting, sawing, filing and / or drilling by known methods.

The core layer according to the invention and a multi-layer composite, which has the core layer according to the invention, for example a lightweight board, have a high compressive and stress resistance. In this regard, the core layer according to the invention and the multi-layer composite produced therefrom according to the invention are superior to the corresponding core layers or multilayer composites produced from industrial waste from chips and fiberboard. In addition, dimensional changes in the core layer or multilayer composite under the influence of moisture, in particular dimensional changes in the thickness of the core layer or of the multi-layer composite, may be negligible due to the negligible dimensional changes of the wood elements in the fiber direction. This is especially true when the fiber direction is in the direction of the at least two adjacent platelet-shaped regions and perpendicular to the edges formed by the contiguous regions. This is a further advantage over other known core layers and multi-layer composites made therefrom, as for example are made of flat particles or layers made with parallel fibers, such as plywood or fiberboard.

Without wishing to be bound by theory, it is believed that the stated advantages result from the structure of the zig-zag wood elements used in the core layer and the multi-layer composite, said edge not being parallel to the grain of the wood element, but preferably perpendicular thereto , Then the structure of the wood element is still supported by the wood fibers, especially at said edge. In contrast, wood elements made from industrial waste have fibers that do not have the same preferred direction but extend isotropically in the three spatial directions. Then the corresponding edges can run parallel to the fiber direction. Therefore, the structure of these wood elements does not or only to a lesser extent said edge assists as compared to wooden elements as used in the core layer and the plate made therefrom according to the invention.

In addition, fasteners such as nails and screws or furniture connectors find in the core layer according to the invention and the multilayer composite according to the invention a reliable hold, since the structure of the core layer at comparatively low density has only small voids, that has a high homogeneity. This can also be a stable attachment to a support, for example on a wall, can be achieved.

Fig. 1a

zeigt einen Querschnitt einer Ausführungsform eines erfindungsgemäßen Mehrschichtverbunds, beispielsweise einer Leichtbauplatte.

Fig. 1b

zeigt einen Querschnitt einer bevorzugten Ausführungsform eines erfindungsgemäßen Mehrschichtverbunds.

Fig. 1c

zeigt einen Querschnitt einer weiteren bevorzugten Ausführungsform eines erfindungsgemäßen Mehrschichtverbunds.

Fig. 2a

zeigt ein zick-zack-förmig ausgebildetes Element und ein ebenes Element einer weiteren bevorzugten Ausführungsform eines erfindungsgemäßen Mehrschichtverbunds bzw. einer erfindungsgemäßen Kernschicht.

Fig. 2b

zeigt ein zick-zack-förmig ausgebildetes Element, welches mit einem ebenflächigen Element verklebt ist.

Fig. 2c

zeigt ein zick-zack-förmig ausgebildetes Element, welches beidseitig mit einem ebenflächigen Element verklebt ist.

Fig. 2d

zeigt mehrere zick-zack-förmig ausgebildete Holzelemente, die im Wechsel mit ebenflächigen Elementen verklebt sind.

Fig. 3

zeigt eine Anordnung von zick-zack-förmig ausgebildeten Holzelementen in der erfindungsgemäßen Kernschicht einer weiteren bevorzugten Ausführungsform eines erfindungsgemäßen Mehrschichtverbunds.

Fig. 4

zeigt eine Anordnung von zick-zack-förmig ausgebildeten Holzelementen der erfindungsgemäßen Kernschicht und eine Deckschicht einer weiteren bevorzugten Ausführungsform eines erfindungsgemäßen Mehrschichtverbunds.

Fig. 5a

zeigt einen Querschnitt eines zick-zack-förmig ausgebildeten Holzelements einer Kernschicht einer weiteren bevorzugten Ausführungsform eines erfindungsgemäßen Mehrschichtverbunds

Fig. 6a

zeigt die Seitenansicht einer für die Herstellung eines zick-zack-förmig ausgebildeten Elements verwendeten Vorrichtung durch Faltung.

Fig. 6b

zeigt die Ansicht in Laufrichtung einer für die Herstellung eines zick-zackförmig ausgebildeten Elements verwendeten Vorrichtung aus Fig. 6a .

Fig. 7a

zeigt die Herstellung eines zick-zack-förmig ausgebildeten Holzelements durch Schneiden mit einem zick-zack-förmig profilierten Messer aus einem Holzblock.

Fig. 7b

zeigt das erhaltene Holzelement aus Fig. 7a .

Fig. 7c

zeigt das durch Schneiden erhaltene Holzelement aus Fig. 7b im zick-zackProfil.

Fig. 8a

zeigt die Herstellung zick-zack-förmig ausgebildeter Holzelemente durch Schneiden in der Seitenansicht.

Fig. 8b

zeigt die Herstellung zick-zack-förmig ausgebildeter Holzelemente aus Fig. 8a in der Draufsicht.

Fig. 9

zeigt zick-zack-förmig ausgebildete Holzelemente, die durch Schneiden mit einem entsprechend profilierten Messer hergestellt werden.

Embodiments of the invention are shown schematically in the drawings. They are explained in more detail below with reference to the figures of the drawings.

Fig. 1a

shows a cross section of an embodiment of a multi-layer composite according to the invention, for example a lightweight board.

Fig. 1b

shows a cross section of a preferred embodiment of a multi-layer composite according to the invention.

Fig. 1c

shows a cross section of another preferred embodiment of a multi-layer composite according to the invention.

Fig. 2a

shows a zigzag-shaped element and a planar element of another preferred embodiment of a multi-layer composite according to the invention or a core layer according to the invention.

Fig. 2b

shows a zigzag-shaped element which is glued to a planar element.

Fig. 2c

shows a zig-zag-shaped element, which is glued on both sides with a planar element.

Fig. 2d

shows several zig-zag-shaped wooden elements that are glued alternately with planar elements.

Fig. 3

shows an arrangement of zig-zag-shaped wooden elements in the core layer according to the invention another preferred embodiment of a multi-layer composite according to the invention.

Fig. 4

shows an arrangement of zig-zag-shaped wooden elements of the core layer according to the invention and a cover layer of another preferred embodiment of a multi-layer composite according to the invention.

Fig. 5a

shows a cross section of a zigzag-shaped wooden element of a core layer of another preferred embodiment of a multi-layer composite according to the invention

Fig. 6a

shows the side view of a device used for the production of a zigzag-shaped element by folding.

Fig. 6b

shows the view in the direction of a device used for the production of a zigzag-shaped element Fig. 6a ,

Fig. 7a

shows the production of a zig-zag-shaped wooden element by cutting with a zig-zag profiled knife from a wooden block.

Fig. 7b

shows the obtained wood element Fig. 7a ,

Fig. 7c

shows the wood element obtained by cutting Fig. 7b in a zig-zag profile.

Fig. 8a

shows the production of zig-zag-shaped timber elements by cutting in side view.

Fig. 8b

shows the production of zig-zag-shaped wooden elements Fig. 8a in the plan view.

Fig. 9

shows zigzag-shaped wooden elements, which are produced by cutting with a correspondingly profiled knife.

Fig. 1a shows a cross section of an embodiment of a multi-layer composite according to the invention 1. The multi-layer composite 1 is designed so that it is a lightweight board. A core layer 3 is covered by the cover layer 2. This is designed as a wood veneer. The core layer 3 comprises wood elements which are shaped so that a wood element has two adjacent platelet-shaped regions which are arranged in a zigzag shape, such that a zick region and the adjacent zack region form a common edge between them such that the wood element is zig-zag shaped, wherein elements in the core layer are arranged so that two such edges of two elements, which may be the same or different from each other, intersect at an angle other than zero, wherein the two elements are firmly connected together at the point of intersection.

The resulting panel 1 is relatively lightweight and has an aesthetically pleasing appearance due to the veneer top layer 2. The average density of the core layer 3 is lower than the average density of the cover layer 2. The wood elements, which may be made of folded veneer pieces, are randomly disposed within the core layer 3. They are connected to each other and to the cover layer 2 by an adhesive. As a result, the lightweight board can withstand shear forces acting on the layers, regardless of the direction of the shear forces in the main plane of the board. This means that the plate has a homogeneous lateral stability. The wooden elements are arranged side by side and / or one above the other. This allows a dense filling of the core layer, whereby the plate receives a high mechanical stability, so that it can be further processed, for example by fitting with nails and screws or furniture connectors. This also allows a stable attachment to a carrier, such as on a wall.

The wood elements are arranged randomly in the core layer 3, but can also be arranged in a regular manner, that is to say in a predetermined manner. For example, the wooden elements can be arranged in an arrangement in a group-like manner, that is, in domains of subunits of the core layer 3, the wooden elements of a first subunit having a first preferred direction and wooden elements of a second subunit having a second preferred direction, preferably the first subunit the second subunit is adjacent and the first preferential direction is preferably different from or at least partially equal to the second preferential direction. A preferred direction may be defined by the edge of a zig-zag wooden element, or may be described by a section of the direction of a wood fiber of a wood element, or may be described by an edge, for example a section of the long edge of a strip-shaped wood element (A strip which has been formed so that it is zig-zag-shaped) or by a connecting line between the edges formed by the zig-zag arranged portions of a zigzag-shaped wooden element.

The multi-layer composite 1 after Fig. 1a has only one cover layer, namely the cover layer 2. A composite with only one-sided cover layer, in comparison to a composite with double-sided cover layers, which surround the core layer sandwich-like, a reduced stability. However, it can serve, for example, as an intermediate for the production of a composite with double-sided outer layers. Such a composite is in Fig. 1b shown.

Fig. 1b shows a cross section of a preferred embodiment of the multi-layer composite according to the invention, namely a cross section of the multi-layer composite 10 in the form of a plate. A cover layer 2 and a further cover layer 2 '(a bottom layer) are provided, wherein the second cover layer 2' of the plate additional gives mechanical stability. The visual appearance of the cover layer 2 'may be different from that of the cover layer 2. Such a composite shows in comparison to the composite Fig. 1a a much higher flexural strength and flexural rigidity.

Fig. 1c shows a cross section of another preferred embodiment of a multi-layer composite according to the invention, namely the multi-layer composite 100 in the form of a plate. The panel has a cover layer 2, a cover layer 2 'and a cover layer 2 "and a further core layer 3' next to the core layer 3. The cover layers 2 and 2 'surround the core layer 3 in a sandwich-like manner, as well as the cover layers 2' and 2 'the core layer 3' sandwich-like. This gives the plate 100 in comparison to the plate 10 additional mechanical stability. The zig-zag-shaped wooden elements in the core layers 3 and 3 'may be random or may be regularly arranged, ie partially regular (for example in domains) or substantially completely regular. The zigzag-shaped wooden elements in the core layer 3 may have a first preferred direction and the zigzag-shaped wooden elements in the core layer 3 'may have a second preferred direction, wherein the first preferred direction is preferably different from the second preferred direction, or at least partially equal to the second preferred direction.

Fig. 3 shows the arrangement of zig-zag-shaped wooden elements 30 in the core layer 3, 3 'of a preferred embodiment of a multi-layer composite 1, 10, 100 according to the invention. Each wooden element 30 has adjoining zigzag and zag regions 50 and 60, which include a form common edge 70 between them. The arrangement of the zig-zag-shaped wooden elements 30 is random. Therefore, the contact surface 40 between adjoining wooden elements is in each case a point 40. When arranging and subsequent bonding, the wood elements generally have point-like joints 40 at the edges 70 crossing at different angles. These joints in turn are partially compressed during the moderate compression by upsetting and thus make possible a homogenization of the structure. Depending on the degree of compaction, a high to medium void fraction remains. This results in a lower density core layer 3, 3 'since alignment of the wood elements 30 does not substantially occur along their respective preferred directions. As a result, the core layer is more anisotropic, which results in an anisotropic mechanical characterization of the resulting plate implies. The resulting structure represents a random truss whose trusses consist of parallel-cased, highly load-bearing wood. The compressed, articulated rod connections are, as is well known in trusses, no weak points, as a truss allows joints. Prerequisite is a sufficient bonding of the joints to absorb longitudinal forces can.

In addition to the resulting from the truss structure high compressive and shear strength and stiffness of the finished lightweight construction element, the very low thickness swelling of the lightweight panel is to emphasize moisture changes due to the virtually negligible swelling of the wood along the grain direction. Thus, such a plate would be superior to all other, built from flat particles or paralleleparous layers of wood materials such as chipboard and fiberboard, plywood or blockboard.

In one embodiment, the zig-zag shaped wooden elements may be blended with planar, e.g. planar formed, elements are combined. Preferably, the zig-zag-shaped wooden elements are glued to the planar elements. This results in the bonding proportionate linear connection points between the zigzag-shaped elements and the planar elements and thus an increased transverse tensile strength of the lightweight board.

Fig. 2a shows two components of a further preferred embodiment of a multi-layer composite 1, 10, 100 according to the invention or a core layer 3, 3 'according to the invention. The core layer 3, 3 'comprises platelet-shaped zig-zag-shaped wooden elements 30, wherein the wooden elements 30 may have a plurality of edges 70 which are formed by adjacent platelet-shaped zigzag and zag regions 50 and 60, for example five edges 70 as in wood element 30 of the Fig. 2a , In addition, there is a planar element 200, which is designed for example as a veneer.

Fig. 2b shows that according to an advantageous variant, a zigzag-shaped element 30 is glued in a first step with a planar element 200 similar or the same format, so that a regular and thus very rigid framework structure in the wood element 30 is formed. The planar element 200 may consist of wood veneer, paper, cardboard or similar, sheet-like materials. The zig-zag-shaped wooden element 30 and the planar element 200 form cavities 300. This framework of the element formed from the planar element 200 and the zig-zag-shaped element 30 remains fully preserved during subsequent compression to a lightweight core. Depending on the location, a local compaction takes place at the joints of these truss-shaped elements. Thus, a high void content 300 remains in the core, which can not be filled by adjacent elements.

This embodiment defines a core layer 3, 3 'which is suitable for a multilayer composite 1, 10, 100 which has at least one cover layer 2, 2', 2 "and a core layer 3, 3 ', the cover layer 2, 2', 2 "is arranged so as to at least partially cover and be in firm connection with the core layer 3, 3 ', the core layer 3, 3' comprising elements 30 of wood having platelet-shaped regions arranged in a zigzag shape wherein a zick region 50 of an element having an adjacent zag portion 60 of the element 30 forms a common edge 70 therebetween, such that the element 30 is formed in a zigzag shape, and elements 30 in the core layer 3 3 'are arranged such that two such edges 70 of two zig-zag-shaped elements 30 cross each other at an angle other than zero, wherein the two zig-zag-shaped elements 30 at the cross-over point are firmly connected with each other; wherein each zig-zag-shaped wooden member 30 is bonded to a planar member 200 such that the zigzag-shaped member 30 and the planar member 200 form one or more cavities 300 therebetween.

Elements after Fig. 2b comprising a zigzag-shaped element 30 and a planar element 200 may be present in random distribution in the core layer 3, 3 '.

It is of course also possible for an item to Fig. 2b comprising a zig-zag-shaped element 30 and a planar element 200 are present together with other zig-zag-shaped elements 30, preferably in random distribution.

This embodiment defines a core layer 3, 3 'which is suitable for a multilayer composite 1, 10, 100 which has at least one cover layer 2, 2', 2 "and a core layer 3, 3 ', the cover layer 2, 2', 2 "is arranged so as to at least partially cover and be in firm connection with the core layer 3, 3 ', the core layer 3, 3' comprising elements 30 of wood having platelet-shaped regions arranged in a zigzag shape wherein a zick portion 50 of an element 30 with an adjacent zag portion 60 of the element 30 form a common edge 70 therebetween such that the elements 30 are zigzag-shaped and zigzag-shaped formed elements 30 in the core layer 3, 3 'are arranged so that two such edges 70 of two zigzag-shaped elements 30 intersect at an angle which is different from zero, wherein the two zigzag formed Elements 30 are fixedly connected together at the point of intersection; wherein the core layer 3, 3 'comprises at least one wood element 30 bonded to a planar element 200 such that the zigzag element 30 and the planar element 200 form one or more cavities 300 between them.

The cavities 300 are formed by the zigzag-shaped portions 50 and 60 in the zigzag-shaped member 30 together with the planar members 200.

Fig. 2c shows that a zigzag-shaped wooden element 30 can also be glued on both sides with planar elements 200 to form cavities 300.

This embodiment defines a core layer 3, 3 'which is suitable for a multilayer composite 1, 10, 100 which has at least one cover layer 2, 2', 2 "and a core layer 3, 3 ', the cover layer 2, 2', 2 "is arranged so that they Core layer 3, 3 'is at least partially covered and in firm connection therewith, wherein the core layer 3, 3' wooden elements 30 having platelet-shaped portions which are arranged in a zigzag, wherein a zick portion 50 of a Elements 30 with an adjacent zack portion 60 of the element 30 form a common edge 70 between them, such that the element 30 is formed zigzag, and wherein elements 30 in the core layer 3, 3 'are arranged so that two such edges 70 of two zig-zag shaped elements 30 intersect at an angle other than zero, the two zigzag-shaped elements 30 being fixedly connected together at the point of intersection; wherein the core layer 3, 3 'at least one zig-zag-shaped wooden element 30 which is glued to two planar elements 200, such that the zig-zag-shaped element and the two planar elements 200 a plurality of cavities 300 between them form, wherein the zig-zag-shaped wooden element 30 is surrounded by the two planar elements 200 sandwich-like.

Fig. 2d shows that several zig-zag-shaped wooden elements 30 can be connected in alternation with planar elements 200 to form cavities 300, wherein a planar element 200 two zig-zag-shaped wooden elements 30 separates from each other.

This embodiment defines a core layer 3, 3 'which is suitable for a multilayer composite 1, 10, 100 which has at least one cover layer 2, 2', 2 "and a core layer 3, 3 ', the cover layer 2, 2', 2 "is arranged so as to at least partially cover and be in firm connection with the core layer 3, 3 ', the core layer 3, 3' comprising elements 30 of wood having platelet-shaped regions arranged in a zigzag shape wherein a zick portion 50 of an element 30 having an adjacent zag portion 60 of the element 30 form a common edge 70 therebetween such that the element 30 is zigzag-shaped and zigzag-shaped formed elements 30 are arranged in the core layer such that two such edges 70 of two zig-zag-shaped elements 30 intersect at an angle other than zero, the two zigzag-shaped elements 30 at the crossover point connected to each other; wherein each two zigzag-shaped elements 30 are bonded to a planar element 200, such that the zigzag-shaped elements 30 and the planar element 200 form a plurality of cavities 300 between them, wherein the planar element 200 of the two zigzag-shaped wooden elements 30 sandwich-like is surrounded.

Elements after Fig. 2d comprising a plurality of zig-zag-shaped wooden elements 30 in alternation with planar elements 200 to form cavities 300, wherein a planar element 200 separates two zigzag-shaped wooden elements 30 from each other, may be present in random distribution in the core layer.

It is of course possible that elements after Fig. 2d comprising a plurality of zigzag-shaped wooden elements 30 in alternation with planar elements 200 to form cavities 300, wherein a planar element 200 separates two zigzag-shaped wooden elements 300 from each other, may be present together with elements 30, preferably in random distribution ,

This embodiment defines a core layer 3, 3 'which is suitable for a multilayer composite 1, 10, 100 which has at least one cover layer 2, 2', 2 "and a core layer 3, 3 ', the cover layer 2, 2', 2 "is arranged so as to at least partially cover and be in firm connection with the core layer 3, 3 ', the core layer 3, 3' comprising elements 30 of wood having platelet-shaped regions arranged in a zigzag shape wherein a zick portion 50 of an element 30 having an adjacent zag portion 60 of the element 30 forms a common edge 70 therebetween such that the element 30 is formed zigzag and zigzag formed elements 30 are arranged in the core layer such that two such edges 70 of two zigzag-shaped elements 30 intersect at an angle other than zero, the two zigzag-shaped element e 30 are firmly connected together at the point of intersection; wherein the core layer 3, 3 'comprises at least one element which has two zigzag-shaped wooden elements 30, which are glued to a planar element 200, such that the two zig-zag formed elements 30 and the planar element 200 form a plurality of cavities 300 between them, wherein the planar element 200 of the two zigzag-shaped wooden elements 30 is sandwich-like surrounded.

In a further embodiment, it is also possible that zig-zag-shaped wooden elements 30 along with elements after Fig. 2b and after Fig. 2c and after Fig. 2d in the core layer 3, 3 'are present. Preferably, the elements in the core layer are then randomly arranged or distributed.

In a further embodiment, it is also possible that zig-zag-shaped wooden elements 30 along with elements after Fig. 2c and after Fig. 2d in the core layer 3, 3 'are present. Preferably, the elements in the core layer are then randomly arranged or distributed.

In a further embodiment, it is also possible that zig-zag-shaped wooden elements 30 along with elements after Fig. 2b and after Fig. 2d in the core layer 3, 3 'are present. Preferably, the elements in the core layer are then randomly arranged or distributed.

In a further embodiment, it is also possible that elements after Fig. 2b and after Fig. 2d in the core layer 3, 3 'are present. Preferably, the elements in the core layer are then randomly arranged or distributed.

In a further embodiment, it is also possible that elements after Fig. 2c and after Fig. 2d in the core layer 3, 3 'are present. Preferably, the elements in the core layer are then randomly arranged or distributed.

Zig-zag-shaped wooden elements, combined with or without even wooden elements, can also be mixed with conventional wood-based elements such as wood chips or wood fibers to form a lightweight core. This glued mixture can be compressed to a light wood-based panel, which has a further increased homogeneity. Particularly advantageous is the applicability of existing technologies such as particle board production, with plat plates are possible with a much lower density than in the conventional plate making.

Fig. 4 shows the arrangement of zig-zag-shaped wooden elements 30 'of the core layer 3, 3' on a cover layer 20 'of another preferred embodiment of a multi-layer composite according to the invention 1, 10, 100. The arrangement of the wood elements is random, resulting in an anisotropic mechanical identification of resulting plate implies. A wood element 30 'is a strip-shaped zig-zag-shaped element having only one edge 70 between adjacent zigzag and zag regions 50 and 60. Generally, a strip-shaped element is an element whose length is greater than the width expressed by a factor c, where c is preferably between the upper and lower limits according to {2; 3; 5} <c <{3;5;8th;10; 20} lies. Of course, the element may also have a plurality of adjoining zigzag and zigzag regions, so that it has a plurality of edges 70.

Fig. 5a shows a cross section of a zigzag-shaped wooden element 7 of a core layer of another preferred embodiment of a multi-layer composite according to the invention, for example, the plate according to the invention. The edge portion 7 'formed between a zigzag and a zigzag portion has a sharp edge. The wood element 7 has only one edge portion, but may also have a plurality of edge portions, as indicated by the dotted lines.

Fig. 6a and 6b show a device with which zigzag-shaped wood elements can be produced by folding. 6a shows the side view the device used for the folding, Fig. 6b the view in the direction of travel.

In this method, veneer or run veneer-like elements such. OSB chips with a production-conditioned wood moisture of at least 30% in a known from the prior art cutting, wherein the wood fiber direction is transverse to the transport direction. This cutting unit separates the veneer or the OSB chips into a strip or wooden elements with a width of optionally 10 to 80 mm. This strip or wooden elements enter a profiling tool, which, starting from the middle, presses in each case a zig-zag profile transversely to the wood fiber direction until the entire width is profiled. The profiling tool is equipped with a heater which heats up the particles after profiling and dries to the moisture required for further processing. At the same time, the springback of the profiling is kept to a minimum. After profiling and drying, the wood elements pass through a Walzenbeleimstation, in which the folding edges are provided on both sides with preferably thermosetting adhesive. The adhesive dries quickly on the still hot particles, it is reactivated during subsequent compression of the particles. Subsequently, the splitting of the profiled wooden elements takes place parallel to the wood fiber direction in 8 to 80mm long parts. Edge sections with correspondingly smaller lengths are also used, as well as sections that arise when splitting the veneer.

To produce a lightweight board, the particles provided with adhesive are scattered onto a prepared cover layer, so that the particles are statistically distributed with respect to direction and position in the surface direction, comparable to other particle materials such as chipboard. After placing the upper cover layer, the plate is made by pressing with moderate pressing pressure, which leads to the contact of the particle edges with each other. By contact heating, high frequency or hot air heating, the curing of the adhesive can be accelerated.

In the production of regular timbered timber elements by connecting zig-zag-shaped wooden elements and planar, ie planar trained, wood elements are both wood element types glued after profiling and synchronously merged and glued.

According to an advantageous variant, the profiling tool is unheated. After profiling, the gluing of the still moist particles with a moisturizing adhesive based on polyurethane and the gluing of zigzag-shaped wood elements and planar wood elements. This gluing fixes the zig-zag profile. This excludes springback.

After bonding, the separation into defined wide parts and finally the compression of the half-timbered particles to a lightweight board.

When still wet particles are processed, the core can be dried by applying air to the side to adjust the final moisture content of the board.

In a first embodiment ( Example 1 ) is a 0.6 mm thick, a wood moisture content of 30%, measured transverse to the wood fiber direction one meter long and 50 mm wide in the grain direction veneer strip 4 on a 5 mm pitch zigzag-like and profiled, profiled, 40 mm wide, heated roller 5 passed and pressed in the center starting from a center profile of the following, heated shoe 6.1 in the profile. This is followed by the sliding shoes 6.2, 6.3, etc., which each press the adjacent profile into the veneer strip until the entire width of the veneer strip is profiled. Gradual profiling from the center guarantees stress-free forming. In the course of the now finished profiled veneer strip 4.1 is held by a likewise heated belt 700 on the roller 5 and thereby dried. This fixes the profiling in the veneer strip. This is followed by a Walzenbeleimstation 800, in which the veneer strip 4.1 is provided at the profile edges with adhesive. Thereafter, the veneer strip 4.1 in a known separation station to 20 mm wide zig-zag-shaped wooden elements, such as the wood elements 30, split. These wooden elements are pressed into a statically highly loadable wooden light building board with a density of 300 kg / m ³ .

In a further embodiment ( Example 2 ) 0.3 mm thick OSB chips with a length of 200 mm and a width of 30 mm are passed transversely to the transport direction in a cutting unit and divided into 40 mm long wooden elements. These wood elements continue into a profiling device according to Example 1, whose zig-zag profile has a grid of 4 mm. The further processing corresponds to Example 1. At the end of processing, a finely divided and homogeneously constructed wood lightweight building board with a density of 250 kg / m ^{3 is formed} . The particular advantage is a largely automatable production.

In a further exemplary embodiment ( Example 3 ), a zigzag-shaped profiled and glued veneer strip according to Example 1 is brought together with a planar veneer strip of width 24 mm and glued to it. This glued tape passes through a Beleimwalzenpaar to provide the tread edges or the outer surface of the planar band with adhesive. After passing through a separation station are particles in the form of a regular framework according to Fig. 2b in front. During pressing, a wooden lightweight building board with a density of 180 kg / m ^{3 is produced} .

Fig. 7a shows the production of a zigzag-shaped wooden element by cutting with a knife 1000 from a block of wood 13. According to the invention used in the production of peeling or sliced veneer or veneer-like chips 1000 profiled zigzag-shaped.

Fig. 7b shows the obtained wood element, such as wood element 30. This can then be crushed, for example in a cutting unit.

Fig. 7c shows a zigzag-shaped wooden element 30 of the Fig. 7b , whereby the zig-zag profile is dimensioned so that the wood fibers 3000 at least twice Length 4000 compared to the thickness of 500 and thus allow a good Querzug- and shear strength. An advantage of this variant is the production of profiled parts in a single operation and the high consistency of the profiles. The oblique to the profile bars extending wood fibers represent a compromise in terms of their strength, as well as the higher thickness swelling.

Fig. 8a and 8b show in a further embodiment ( Example 4 ) a device for the production of zig-zag shaped wooden elements by cutting. Fig. 8a shows the side view, Fig. 8b the top view. In this case, on a known veneer knife machine of a 400 mm high wood block 13 by means of a zigzag-shaped profiled knife 1000 with a profile grid size of 5 mm profiled veneer 400 11 height of 3mm is cut. The thickness of the profiled veneer (500 in Fig. 7c ) is 0.5mm. On the profile knife 1000 are at a distance of 25 mm scoring knife 12 attached, which cut the resulting profiled veneer 400 in 25 mm wide and 400 mm long strips. These strips whose wood fiber direction is transverse to the longitudinal axis are comminuted in a known hammer mill to wood elements with an average width of 16 mm, for example, wood elements 30. It joins the drying, sifting and gluing in known drums, whereupon the prepared zick -Zack-shaped wooden elements by means of known scattering machines scattered to a nonwoven and pressed together with outer layers to a lightweight board with a density of 350 kg / m ³ .

In a further exemplary embodiment ( example 5 ), a knife disc chipper customary in chipboard technology is equipped with knives profiled with zigzag-shaped knives having a profile grid dimension of 3 mm, the set chip thickness being 0.3 mm. The attached scoring blades have a distance of 20 mm. Starting product are roundwood sections, peeling residual rolls and other residual materials. The wood elements produced with this chipper are further processed according to Example 4. A particular advantage of this technology is the comparability with the highly productive production of chipboard, which results in a very cost-effective lightweight wood construction material.

In a further embodiment (Example 6 ) a veneer peeling machine is equipped with a knife according to Example 4. The correspondingly profiled veneer web produced from a peeling block passes through a veneer drier, a roller gluing machine and finally a contact press in which a board web is pressed. Subsequently, the distribution of this web by means of known cutting units in 25 x 25 mm ² large wooden elements, which represent regular trusses. After inspection and removal of unusable portions of these wood elements are provided in a Beleimtrommel with adhesive and then pressed into a wood corrugated board with a density of 200 kg / m ³ . Advantageous here is the usability of inferior wood assortments that are not suitable for the usual veneer production.

Fig. 9 shows zig-zag-shaped wooden elements 30 ", which are produced by cutting with a correspondingly profiled knife, which have no constant profile thickness.These are characterized by an increased compressive strength.The cutting direction in the manufacture of the elements can with each new cutting stroke in The geometry and thus also the stability of the veneer pieces caused by the fiber progression changes with a maximum difference of the cutting directions by 90 °, the produced "profiled wood element ", depending on the cutting thickness, has a grid structure In addition to solid wood, wooden materials, which have approximately the same strength properties in different sheet directions, are suitable as starting material, for example residual or waste pieces made of plywood or medium-density fibreboard can be used for this purpose.

LIST OF REFERENCE NUMBERS

1, 10, 100

Multilayer

2, 2 ', 2 ", 20'

topcoat

3, 3 '

core layer

7, 8, 30, 30 ', 30 "

zig-zag shaped wooden element

50

zigzag or zigzag area

60

zack or zick area

7 ', 8', 70

Edge between a zick area and an adjacent zack area; or edge between a zigzag area and an adjacent zig area

40

Contact surface or point of contact between two intersecting edges 7 ', 8', 70th

200

planar element (planar element)

300

Cavity, which by a zig-zag-shaped wooden element 7, 8, 30, 30 ', 30 "formed by gluing with a planar element 200

4

veneer tape

4.1

profiled veneer strip

5

roller

6.1, 6.2, 6.3 ...

skids

700

heated band

800

Walzbeleimstation

13

wood block

3000

wood fibers

4000

Length of wood fibers 3000

500

Thickness of a zigzag or zig portion 50, 60 of a wood element 7, 8, 30, 30 ', 30 "

1000

zig-zag profiled knife

400

veneer

11

Thickness of the veneer 400

12

scoring knife

L

Length of an edge 7 ', 8', 70th

H

Height of a zig-zag-shaped wooden element 7, 8, 30, 30 ', 30 "

Claims (13)

1. Core layer (3, 3'), which is suitable for a multilayer composite (1, 10, 100) comprising at least one cover layer (2, 2', 2", 20') and a core layer (3, 3'), wherein the cover layer (2, 2', 2", 20') is arranged such that it at least partially covers the core layer (3, 3') and is fixedly connected thereto, wherein the core layer (3, 3') comprises wooden zigzag-shaped elements (7, 8, 30, 30', 30"), comprising zigzagging laminar regions, wherein a zig region (50) of an element (7, 8, 30, 30', 30"), together with an adjoining zag region (60) of the zigzag-shaped element (7, 8, 30, 30', 30"), form between them a common edge (7', 8', 70), and wherein zigzag-shaped elements (7, 8, 30, 30', 30") are arranged in the core layer (3, 3') such that two such edges (7', 8', 70) of two zigzag-shaped elements (7, 8, 30, 30', 30"), which can be the same or different from each other, intersect at an angle which is different from zero, the two elements (7, 8, 30, 30', 30") being fixedly connected to each other at the point of intersection (40);
   wherein more than 50 % of the wooden elements (7, 8, 30, 30', 30") are present in the core layer (3, 3') such that they are fixedly connected to each other, wherein the wooden elements (7, 8, 30, 30', 30") are randomly distributed; or
   wherein the wooden elements (7, 8, 30, 30', 30") are randomly arranged in the core layer (3, 3'), wherein they are connected to one another and with a cover layer (2, 2', 2", 20') by means of an adhesive, wherein the wooden elements (7, 8, 30, 30', 30") are arranged side by side and one above the other or are arranged side by side or one above the other; or
   wherein the wooden elements (7, 8, 30, 30', 30") are randomly arranged in the core layer (3, 3'), wherein the wooden elements (7, 8, 30, 30', 30") upon arranging and the subsequent bonding generally have dot-like connecting points (40) at the edges (7', 8', 70) which intersect at different angles;
   characterized in that
   said zigzag-shaped wood elements (7, 8, 30, 30', 30") comprise fibres (3000) having a preferred direction, wherein the common edge or the common edges (7', 8', 70) runs or run non-parallel to the preferred direction; or
   wherein the common edge or the common edges (7', 8', 70) runs or run perpendicular to the preferred direction.
2. Core layer (3, 3') according to Claim 1, wherein zigzag-shaped wood elements (7, 8, 30, 30', 30") comprise repeating units of zig and zag regions (50) and (60), wherein the common edges (7', 8', 70) formed between the regions run parallel to one another.
3. Core layer (3, 3') according to claim 1, wherein the length (4000) of the fibres (3000) of a zigzag-shaped wood element (7, 8, 30, 30', 30") is at least twice as long as the thickness (500) of a zig or zag region (50) or (60) of the zigzag-shaped wood element (7, 8, 30, 30', 30").
4. Core layer (3, 3') according to one of the preceding claims, wherein the thickness (500) of a zig or zag region (50) or (60) lies in the range from 0.2 mm to 2 mm, and/or the height H of a zigzag-shaped element (7, 8, 30, 30', 30") lies in the range from 0.8 mm to 8 mm, and/or the length L of an edge (7', 8', 70) lies in the range from 0.5 cm to 10 cm; or
   wherein the height (H) of a zig or zag region (50) or (60) measures no more than one-tenth of the thickness of the core layer (3, 3').
5. Core layer (3, 3') according to one of the preceding claims, wherein each zigzag-shaped wood element (7, 8, 30, 30', 30") is bonded to a planar element (200), such that the zigzag-shaped element (7, 8, 30, 30', 30") and the planar element (200) form between them one or more cavities (300).
6. Core layer (3, 3') according to one of Claims 1 to 4, wherein the core layer (3, 3') comprises at least one zigzag-shaped wood element (7, 8, 30, 30', 30"), which is bonded to a planar element (200) such that the zigzag-shaped element (7, 8, 30, 30', 30") and the planar element (200) form between them one or more cavities (300).
7. Core layer (3, 3') according to one of Claims 1 to 4, wherein the core layer (3, 3') comprises at least one zigzag-shaped wood element (7, 8, 30, 30', 30"), which is bonded to two planar elements (200) such that the zigzag-shaped element (7, 8, 30, 30', 30") and the planar elements (200) form between them a plurality of cavities (300), wherein the zigzag-shaped wood element (7, 8, 30, 30', 30") is surrounded in a sandwich-like manner by the plane elements (200).
8. Core layer (3, 3') according to one of Claims 1 to 4, wherein the core layer (3, 3') comprises at least one element comprising two zigzag-shaped wood elements (7, 8, 30, 30', 30"), which are bonded to a planar element (200) such that the zigzag-shaped elements (7, 8, 30, 30', 30") and the planar element (200) form between them a plurality of cavities (300), wherein the planar element (200) is surrounded in a sandwich-like manner by the two zigzag-shaped wood elements (7, 8, 30, 30', 30").
9. Core layer (3, 3') according to any one of the preceding claims, wherein said edge (7', 8', 70) includes a sharp edge in the form of a line or a wavy or corrugated edge in the form of a curve-shaped plane or a curved region between a zig region (50) and a zag region (60).
10. Method for producing a core layer (3, 3') according to one of the preceding claims, at least comprising the steps (i) to (iii):

    (i) presenting zigzag-shaped wooden elements (7, 8, 30, 30', 30"), which comprise zigzagging laminar regions, wherein a zig region (50) of an element (30), together with an adjoining zag region (60) of the element (7, 8, 30, 30', 30"), form between them a common edge (7', 8', 70);

    (ii) arranging the elements (7, 8, 30, 30', 30") from step (i) such that two such edges (7', 8', 70) of two elements (7, 8, 30, 30', 30") intersect at an angle which is different from zero;

    (iii) fixedly connecting of the edges (7', 8', 70) from step (ii), preferably by means of an adhesive.
11. Multilayer composite (1, 10, 100), at least comprising a cover layer (2, 2', 2", 20') and a core layer (3, 3'), wherein the cover layer (2, 2', 2", 20') is arranged such that it least partially covers the core layer (3, 3') and is fixedly connected thereto, wherein the core layer (3, 3') is a core layer (3, 3') as defined in one of claims 1 to 10.
12. Multilayer composite (1, 10, 100) according to claim 11, wherein the cover layer comprises a material selected from: veneer, woodboard, chipboard, fibreboard, plywood board, plastics sheet, plasterboard, sheet metal, fibre cement board, and from two or more thereof.
13. Use of a core layer (3, 3') according to one of claims 1 to 9; or use of a multilayer composite (1, 10, 100) according to claim 11; in furniture production, for shelving, for packagings for transport, for interior fittings, in doors and gates, as well as in vehicle construction and shipbuilding.

Images