DE102017118877A1 - Composite panel and apparatus and method for its production - Google Patents

Abstract

The present application relates to a composite panel (1) comprising
- At least one outer layer (2, 3) and
at least one filling layer (4) in contact with the outer layer (2, 3), the outer layer (2, 3) comprising at least one fabric layer, the filling layer (4) being formed by a plastic foam, the outer layer (2, 3) and the filling layer (4) are interconnected in force transferring manner, so that a one-piece composite plate (1) results.
In order to provide a composite panel which is easier to produce compared to the prior art, it is proposed according to the invention that a contact zone (5) between the outer layer (2, 3) and the filling layer (4) is made free of adhesive.
Furthermore, the present application relates to a device (10) and a method for producing such a composite plate (1).

Description

introduction

The present application relates to a composite panel comprising at least an outer layer and a filler layer. Furthermore, the application relates to a device for producing such a composite plate, wherein the device comprises two half-shells corresponding to one another, within which the filling layer can be foamed onto the outer layer. Finally, the present application further comprises a method for producing a composite panel according to the invention using a device according to the invention.

For the purposes of the present application, an "outer layer" is to be understood in principle as any type of layer which forms an outer end of the composite panel. However, in each case, the outer layers are present individually in the course of producing the composite panel at one time, that is, independently of the filling layer. Thus, for example, forms an outer region, for example, a foamed material, such as a sponge, which is integrally formed with the remaining material, although an outer end of this sponge, but nevertheless not as "outer layer" within the meaning of the present application understandable, since the outer region the sponge was not at any time individually and independently of the remaining material. In particular, the outer layers can be designed to be flexible and pressure-resistant before interacting with the filling layer. In particular, an outer layer may be formed by a film, a paper or a laminate, wherein the laminate may in particular be an HPL (high pressure laminate) or a CPL (continuous pressure laminate).

A "fabric layer" in this context describes a single layer of a respective outer layer, wherein in particular an outer layer formed by a laminate comprises a plurality of fabric layers. These fabric layers may be formed, for example, by decorative paper or top paper or kraft paper. Such a fabric layer can be impregnated, such "impregnation" in the sense of the present application describing a treatment of a respective fabric layer with an impregnating substance which alters the mechanical properties of the original fabric layer. In particular, the impregnation can lead to an increase in the strength and the rigidity of the respective fabric layer. Also, the fabric layer can be rendered hydrophobic by impregnation. For example, an impregnated fabric layer may be formed by a decorative paper soaked with melamine resin or a kraft paper impregnated with phenolic resin.

For the purposes of the present application, a "plastic foam" is understood as meaning a foam formed by plastic, which may be, in particular, hard, that is to say pressure-resistant. The production of such a foam typically takes place by means of a chemical reaction. This is known in particular from polyurethane foam, which is a plastic foam in the sense of the present application.

In principle, a "force-transmitting connection" can be understood as any type of connection which is suitable for transmitting forces between the interconnected parts. Such a connection can be formed in particular by means of adhesion.

State of the art

Composite panels are already well known in the art. For this purpose, reference is made in particular to the International Patent Application WO 2011/015376 A1 pointed. This describes a composite panel comprising a filler layer and at least one outer layer. For the purposes of the present application, the carrier describes a filling layer, while the composite plate forms an outer layer. The application has set itself the task to produce as light composite panels with good mechanical properties that are as easy to work.

Furthermore, the International Patent Application describes WO 2009/033672 a composite panel comprising facing cover layers and an intermediate core layer. The latter application has set itself the task of providing a composite panel with good mechanical properties, the focus was on lightweight and yet rigid composite panels.

The known composite panels have the disadvantage that their production is comparatively complicated and requires a precise matching of the outer layers to the core layer, including an adhesive that connects the layers.

task

The present application is therefore based on the object to provide a composite plate, which is easier to manufacture compared to the prior art.

solution

The underlying object is achieved by means of a composite panel having the features of claim 1. This composite panel is characterized characterized in that a contact zone, in which the outer layer and the filling layer come into at least indirect contact, is carried out without adhesive. In other words, the filling layer and outer layer come into direct contact with each other, wherein the force-transmitting connection between the two layers alone and exclusively by means of the adhesive action of the Füllschichtmaterials, that is the plastic foam, is generated itself. An additional adhesive, as used in the prior art in any case, is not used and does not exist.

The composite panel according to the invention has many advantages. In particular, their production is simplified compared to the prior art, since the application of a specially adapted to the materials used and applied adhesive, such as a wood glue or the like, can be completely eliminated. As a result, the production of a composite panel according to the invention is significantly simplified. The invention is based on the finding that the plastic used as filling layer material can form a pronounced immediate contact zone with the at least one outer layer in the course of its processing and also develops a high adhesive effect. As a result, the outer layer and the filling layer are firmly bonded together without the use of a dedicated adhesive. The connection between the outer layer and the filling layer can in particular achieve such a strength that in the course of a determination of the surface strength of the composite plate after DIN EN 13894-1 the composite plate fails not in the contact zone, but in the filling layer.

Advantageously, the composite panel according to the invention comprises two mutually opposite outer layers, which enclose the filling layer between them. Preferably, both contact zones between the outer layers and the filling layer are each made adhesive-free.

Furthermore, such a composite plate may be advantageous in which the plastic foam of polyurethane foam, in particular of rigid polyurethane foam is formed. Polyurethane (hard) foam is particularly easy to produce and suitable in terms of its mechanical and chemical properties for a wide range of applications.

In an advantageous embodiment of the composite panel according to the invention, air pores within the filler layer are distributed unevenly over a thickness of the filler layer measured perpendicular to the at least one outer layer. In particular, the air pores, based on a volume fraction in the filling layer, continuously decrease starting from a central region towards the outer layer. It is understood that air pores in the course of the foaming of the plastic mandatory and are entered in the desired manner in the filling layer. For the best possible formation of the contact zone between the outer layer and the filling layer, it is nevertheless advantageous if within the said contact zone, which adjoins directly to an inwardly directed surface of the respective outer layer, as few air pores as possible to the immediate contact between the Fill layer material and the surface of the outer layer to produce. As a result, the connection between the outer layer and the filling layer is improved as a result. Advantageously, the volume fraction of the air pores in the region of the contact zone is at most 5%.

For the above-mentioned consideration, it is also advantageous if at least 90%, preferably at least 92.5%, more preferably at least 95%, of a surface of a respective outer layer facing the filling layer are in direct contact with the filling layer material. In this way, a good power transmission between the outer layer and the filling layer is ensured.

The at least one outer layer is preferably formed by a so-called laminate comprising a plurality of layers pressed together. These layers may in particular be formed by four impregnated fabric layers, wherein an uppermost layer of an impregnated decorative paper and three successive underlying layers may each be formed by an impregnated kraft paper. The decorative paper fulfills in particular an aesthetic function and forms a conclusion of the outer layer or the laminate plate to the outside, while the kraft papers of the outer layer give positive mechanical properties, in particular a compressive and flexural strength. Preferably, the decorative paper has a basis weight of from 80 g / m ² to 140 g / m ² . Irrespective of this, each of the kraft papers preferably has a basis weight of 150 g / m ² to 300 g / m ² . A finished outer layer may in particular have a density of 1400 kg / m ³ .

As an alternative to a multilayer laminate panel, a respective outer layer may be formed by a single layer, namely an impregnated decorative paper. Such an embodiment is more advantageous than a multilayer laminate panel, but is disadvantaged in its durability over the latter. Likewise, an outer layer may be formed by a film.

Regardless of the type of outer layer can be the impregnation of the individual layers be made in particular by means of a melamine resin or a phenolic resin, melamine resin can be used in particular for decorative papers and phenolic resin for Kraft papers.

The underlying object is further achieved by means of a device having the features of claim 9. This comprises two mutually corresponding half-shells which together define an interior when present in a closed position. The interior is filled with foamable plastic, in particular polyurethane, and closed. In the course of the subsequent foaming of the plastic towards a plastic foam whose volume increases sharply, so that the plastic extends to at least one arranged on one of the half-shells outer layer and establishes a connection with this. In the course of the reaction of the plastic foam, a permanent, adhesive bond between the plastic foam and the respective outer layer is produced.

Advantageously, both half shells of the device are each provided with an outer layer, so that the plastic foam is formed between two outer layers. Furthermore, the plastic foam is advantageously formed by polyurethane foam, in particular rigid polyurethane foam.

For introducing the materials into the interior of the device, that is to say both for positioning the outer layer (s) and for introducing the plastic, the device can be moved to an open position, for which purpose the two half shells are movable relative to each other, in particular pivotable. After filling in particular of the plastic half shells are closed as quickly as possible to provide the plastic only limited space for expansion or foaming available. This results in a certain intrinsic compression of the filling layer material, which ultimately causes the good mechanical properties of the finished filling layer. For mechanical relief of the half-shells during the foaming of the plastic, the device according to the invention has at least one pressure relief valve, through which the foaming filling layer material can escape from the interior.

In an advantageous embodiment of the device according to the invention, at least one of the half shells cooperates with a rotary joint, which ensures the necessary mobility of the half shells relative to one another. In particular, a lower half-shell can be designed to be stationary, while the upper can be pivoted freely relative to the lower half-shell by means of the rotary joint.

For producing large composite panels, it is advantageous if the half-shells have a length of at least 2.0 m, preferably at least 2.2 m, more preferably at least 2.4 m, and a width of at least 0.8 m, preferably at least 0, 9 m, more preferably at least 1.0 m. In addition, the composite panels to be produced are advantageously as thin as possible, so that they can be used, for example, for cladding walls and / or building components while taking up little space. Accordingly, it is advantageous if a height of the interior of the device (at least in the presence of the device in its closed position) is a maximum of 2.0 cm, preferably a maximum of 1.5 cm, more preferably a maximum of 1.0 cm.

Furthermore, such a device may be of particular advantage, in which the surfaces of the half-shells are at least substantially, preferably completely, flat or flat, at least outside an edge region of the respective half-shell. The flat design is particularly well suited to produce also plan formed composite panels.

Furthermore, such a device is particularly advantageous, the half shells are horizontally oriented in the closed position in the presence of the device and arranged one above the other. A respective outer layer can then be particularly easily placed on a surface of the lower half-shell prior to filling the interior with the plastic. Only the upper half-shell possibly requires a receptacle by means of which a possible upper outer layer can be stored on the half-shell. In particular, it must then be ensured that this upper outer layer does not "drop" so that the device can be closed and still leave space between the outer layers for the filling layer.

Finally, the underlying object is achieved by means of a method having the features of claim 14. The method is particularly simple to carry out by means of the device according to the invention, in order to ultimately obtain a composite panel according to the invention.

The method is particularly advantageous insofar as it requires no application of an adhesive of any kind in order to connect the outer layers and the filling layer with each other. Instead, the foamable plastic can readily be filled into the interior of the device, whereupon the device is closed. The plastic, preferably polyurethane, then foams up, as a result of which it increases its volume drastically and rests flat against the surface of the at least one outer layer. As a result, the outer layer and the filling layer form an immediate contact zone which makes the force transferring connection between the layers.

In order to avoid inadvertent opening of the device in the form of inadvertently moving half shells relative to each other, the device is preferably closed after filling the interior with plastic and the subsequent closing of the device such that the half shells can no longer move relative to each other. For this purpose, in particular a closing device, for example in the form of a clamp or a screw, can be used.

After foaming and at least partial curing of the filling layer material, the device is transferred to its open position, whereupon the composite plate can be removed from the device. In order to ultimately obtain a marketable product, it may then be necessary to cut the composite panel, for example, to cut off protruding edges of the cured filler. Also, a cut to certain formats is conceivable.

In the course of the method, an upper of the two half-shells in the course of the foaming of the plastic is advantageously pressed upwards by means of the plastic such that the upper half-shell at least substantially, preferably completely, extends over its entire surface parallel to the lower half-shell. Since the half-shells for the production of a large-area composite panel may in particular have dimensions in the range of more than 3.0 m × 1.0 m, it may happen that the upper half-shell "sags" in a central region due to its own weight. This of course affects the height of the interior, which would therefore not be constant across a width and length of the device. According to the advantageous method, the foaming plastic and the pressure generated by it inside the interior are now used to "push up" the upper half-shell so that an irregularity in the course of the height of the interior is compensated over the device. In this way it is ensured that the finished composite panel has a constant thickness throughout.

list of figures

• 1: Eine isometrische Ansicht einer erfindungsgemäßen Verbundplatte,
• 2: Einen Querschnitt durch die Verbundplatte gemäß 1,
• 3: Einen schematischen Querschnitt durch eine erfindungsgemäße Vorrichtung bei Vorliegen in ihrer Geschlossenposition,
• 4: Die Vorrichtung gemäß 4 in ihrer Offenposition und
• 5: Die Vorrichtung gemäß 4 nach Abschluss des erfindungsgemäßen Verfahrens.

The composite panel as well as the apparatus and the method will be explained below with reference to an embodiment which is illustrated in the figures. It shows:

• 1 : An isometric view of a composite panel according to the invention,
• 2 : A cross section through the composite panel according to 1 .
• 3 FIG. 2: shows a schematic cross section through a device according to the invention when in its closed position, FIG.
• 4 : The device according to 4 in their open position and
• 5 : The device according to 4 after completion of the process according to the invention.

The embodiment that is in the 1 to 5 is shown, comprises a composite panel according to the invention 1 , the two opposing outer layers 2 . 3 and a fill layer therebetween 4 includes. the outer layers 2 . 3 are here each formed by a four-layer laminate whose top layer of an impregnated decorative paper and three underlying layers are each made of impregnated kraft paper. The filling layer 4 here is made of rigid polyurethane foam. The composite panel 1 has a thickness 6 on, perpendicular to the outer layers 2 . 3 is measured. The composite panel 1 here has a length of 3.1 m and a width of 1.3 m, while the thickness 6 about 0.8 cm. She is particular in 1 recognizable.

The outer layers 2 . 3 form together with the filling layer 4 each contact zones 5 which is particularly good on the basis of 2 are recognizable. Within the contact zone, the filling material form the filling layer 4 and the outer layers 2 . 3 According to the invention, an immediate contact, the force-transmitting connection between the outer layers 2 . 3 and the filling layer 4 allows. The contact zone 5 is completely free of glue or any other adhesive. Instead, the force transferring connection between the outer layers 2 . 3 and the filling layer 4 solely by means of an adhesive bond of the filler material to a respective surface 8th . 9 the respective outer layer 2 . 3 causes.

The polyurethane foam comprises a large number of air pores. These are inherently present in the rigid polyurethane foam. The air pores are uneven across the thickness here 6 the filling layer 4 distributed, as is purely qualitative from the representation according to 2 results. In a middle area 7 the composite panel 1 is an air entrainment largest. The latter takes on the basis of said middle range 7 each to the outer layers 2 . 3 from, preferably continuously. This type of air pore distribution can be achieved particularly easily by means of the method according to the invention, as will be apparent separately below.

In particular, the air pore distribution is designed such that the air entrainment within the contact zone 5 maximum 5%. In the example shown it is about 3%. This has the advantage that the surface 8th . 9 the respective outer layer 2 . 3 forms as large a contact surface with the filling layer material, which in turn makes the adhesive connection between the filling layer 4 and the outer layers 2 . 3 is ensured.

The composite panel according to the invention 1 is by means of in the 3 to 5 illustrated device 10 been prepared. This includes two half shells 11 . 12 that here in the presence of the device 10 in their in 3 illustrated closed position are oriented at least substantially horizontally. The half-shells 11 . 12 correspond to each other so that they have an interior 13 limit or limit. Typically, the half shells 11 . 12 at least substantially the same. The upper half shell 11 is by means of a swivel joint 23 about an axis of rotation relative to the lower half shell 12 pivoted so that the device 10 between the closed position and an open position can be transferred. The latter is particularly well based on 4 ,

According to the dimensions of the composite panel 1 is a width 14 the half-shells 11 . 12 here about 1.4 m, a length not visible in the figures about 3.4 m and a height 17 about 1.2 cm. A clear height 15 between the outer layers 2 . 3 , to a certain extent the height of the interior 13 corresponds to, here is 1.0 cm. The slight excess of the device 10 opposite the composite panel 1 is by border areas 20 the half-shells 11 . 12 justified, the full exploitation of the interior 13 prevent. Outside the border areas 20 are the half-shells 11 . 12 completely flat here.

In the example shown, the upper half shell is 11 with a plurality of pressure relief valves 16 equipped, of which in 4 two are recognizable. The pressure relief valves 16 serve to excess filler in the course of its foaming from the interior 13 to be able to drain to damage the device 10 as well as to prevent a possibly incomplete reaction of the filling layer material. An exemplary exit of filling layer material is in particular in 5 recognizable.

Starting from its closed position, the device 10 first pivoted to its open position ( 4 ). Before filling the interior 13 With the filling layer material, that is to say polyurethane here, first the outer layers on the half shells 11 . 12 arranged. For this purpose, at least the upper half shell 11 about recordings 21 , by means of which the associated outer layer 2 on the half shell 11 is storable. After the introduction of the outer layers 2 . 3 is the unfoamed, yet foamable filler material in the form of polyurethane 22 on the lower outer layer 3 given up. Subsequently, the upper half shell 11 pivoted down, so that the device 10 is transferred to their closed position. This happens under a certain time pressure, since the polyurethane 22 typically immediately begins to foam.

To a foam pressure of the polyurethane 22 to be able to resist, the half-shells 11 . 12 in the presence of the device 10 in its closed position in the example shown by means of a closing device 24 locked. The latter blocks inadvertent pivoting of the half-shells 11 . 12 relative to each other.

In the course of the foaming, the filling layer material expands strongly, whereby within the interior 3 an internal pressure arises. In other words, the polyurethane pushes 22 against inner surfaces of the device 10 , so too against the interior 13 directed surfaces 8th . 9 the outer layers 2 . 3 , The outer layers 2 . 3 can - supported by the half shells 11 . 12 - the pressure of the polyurethane 22 do not give in while in the middle section 7 the later filler layer 4 there is a certain possibility of expansion. Due to these conditions, it comes to the above-described embodiment of the air-pore distribution within the filling layer 4 ,

After curing of the filling layer material, the device 10 be transferred back to their open position, whereupon the composite panel 1 from the device 10 can be removed. The latter is then ready for the production of another composite panel. The removed composite plate 1 can now be tailored as needed.

LIST OF REFERENCE NUMBERS

1

sandwich panel

2

outer layer

3

outer layer

4

filling layer

5

contact zone

6

thickness

7

the central region

8th

surface

9

surface

10

contraption

11

half shell

12

half shell

13

inner space

14

width

15

height

16

Pressure relief valve

17

height

18

surface

19

surface

20

border area

21

admission

22

polyurethane

23

swivel

24

closing

QUOTES INCLUDE IN THE DESCRIPTION

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

Cited patent literature

• WO 2011/015376 A1 [0006]
• WO 2009/033672 [0007]

Cited non-patent literature

• DIN EN 13894-1 [0011]

Claims (16)

Composite panel (1), comprising - at least one outer layer (2, 3) and - at least one filling layer (4) in contact with the outer layer (2, 3), the outer layer (2, 3) comprising at least one layer of fabric, wherein the Filling layer (4) is formed by a plastic foam, wherein the outer layer (2, 3) and the filling layer (4) are connected to each other in a force-transmitting manner, so that a one-piece composite plate (1) results, characterized in that a contact zone (5 ) between the outer layer (2, 3) and the filling layer (4) is made adhesive-free. Composite plate (1) after Claim 1 , characterized by two opposing outer layers (2, 3), which enclose the filling layer (4) between them, wherein preferably both contact zones (5) between each of the outer layers (2, 3) and the filling layer (4) are made adhesive-free. Composite plate (1) after Claim 1 or 2 , characterized in that the plastic foam of polyurethane foam, in particular of rigid polyurethane foam, is formed. Composite panel (1) according to one of Claims 1 to 3 wherein the filling layer (4) has air pores, characterized in that the air pores are unevenly distributed over a thickness (6) of the filling layer (4) measured perpendicular to the at least one outer layer (2, 3). Composite plate (1) after Claim 4 , characterized in that an air entrainment proportion corresponding to a volume fraction of the air pores on an entire viewing volume of the filling layer (4) is greatest in a middle region (7) of the filling layer (4) and towards the at least one outer layer (2, 3) decreases, preferably to a volume fraction of not more than 5% in the contact zone (5). Composite panel (1) according to one of Claims 1 to 5 , characterized in that at least 90%, preferably at least 92.5%, more preferably at least 95%, of a respective surface (8, 9) facing the filling layer (4) of the at least one outer layer (2, 3) directly with the plastic foam stay in contact. Composite panel (1) according to one of Claims 1 to 6 , characterized in that the outer layer (2, 3) is formed by a laminate comprising four impregnated fabric layers, namely an upper decor paper and three Kraft papers, preferably the decorative paper has a basis weight of 80 g / m ² to 140 g / m ² and the Kraft papers each have a basis weight of 150 g / m ² to 300 g / m ² . Composite panel (1) according to one of Claims 1 to 6 , characterized in that the outer layer (2, 3) is formed by an impregnated decorative paper. Composite panel (1) according to one of Claims 1 to 6 , characterized in that the outer layer (2, 3) is formed by a film. Device (10) for producing composite panels (1) according to one of Claims 1 to 9 comprising two half-shells (11, 12) which are movable relative to one another, so that the device (10) can be moved between an open position and a closed position, the two half shells (11, 12) being in the closed position when the device (10) is present together define a plate-shaped interior (13) whose length and width (14) each clearly exceed its height (15), and wherein in the presence of the device (10) in its open position, the device (10) is opened such that its interior ( 13) is accessible from an environment, so that materials to be processed in the interior (13) can be introduced, wherein the two half-shells (11, 12) in the presence of the device (10) in its closed position in force transmitting manner are connected to each other, so the relative mobility of the half shells (11, 12) is blocked to each other, wherein the device (10) has at least one pressure relief valve (16) by means of in the presence of the device (10) in its closed position in the interior (13) befindliches material when crossing an internal boundary pressure within the interior (13) from the interior (13) can escape outward. Device (10) according to Claim 10 , characterized in that the half-shells (11, 12) are pivotable relative to each other, wherein preferably one of the half-shells (11) cooperates with a rotary joint (23). Device (10) according to Claim 10 or 11 , characterized in that the half-shells are each at least 1.5 m, preferably at least 2.0 m, more preferably at least 2.5 m, long and at least 0.5 m, preferably at least 1.0 m wide, preferably one Height (17) of the interior measured between the half-shells (11, 12) in the closed position when the device (10) is present is not more than 2.0 cm, preferably not more than 1.5 cm, more preferably not more than 1.0 cm. Device (10) according to one of Claims 10 to 12 , characterized in that the interior (13) facing surfaces (18, 19) of the half-shells (11, 12) at least outside of an edge region (20) at least substantially, preferably completely, are flat. Device (10) according to one of Claims 10 to 13 , wherein the half-shells (11, 12) are each aligned horizontally in the closed position in the presence of the device (10), so that the half-shells (11, 12) are arranged one above the other, characterized in that at least the upper of the two half-shells (11) Receiving (21), by means of which an outer layer (2) in force transmitting manner on the half-shell (11) can be stored. Method for producing a composite panel (1) according to one of Claims 1 to 8th by means of a device according to one of Claims 9 to 13 comprising at least one half shell (11) of the device (10) is moved relative to the other half shell (12) such that the device (10) is transferred to its open position. b) At least one of the half-shells (11, 12) is equipped with an outer layer. c) Foam-filled plastic is introduced into the interior (13) of the device (10) that is open in its open position relative to the environment because of the presence of the device (10). d) The half-shells (11, 12) are moved relative to each other, that the device (10) is transferred to its closed position in which the interior (13) of the device (10) is closed to the environment so that an accidental leakage the plastic in the course of its foaming from the interior (13) out is at least substantially prevented. e) The half-shells (11, 12) are in the closed position in force transmitting manner connected to each other in the presence of the device (10), so that a movement of the half-shells (11, 12) is blocked relative to each other. f) After complete foaming of the plastic, which then forms the filling layer (4), the half shells (11, 12) are pivoted relative to each other, so that the device (10) is transferred to its open position, in which the composite plate (1) the at least one outer layer (2, 3) and the filling layer (4) fixedly connected thereto and formed by the foamed plastic, can be removed from the device (10). g) The composite panel (1) is removed from the device (10). Method according to Claim 15 , characterized in that the one upper of the two half-shells (11, 12) is pushed in the course of the foaming of the plastic by means of the plastic upwards, that the upper half-shell (11) at least substantially, preferably completely, over its entire surface extending parallel to the lower half-shell (12).

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