Artificial panel with coated and sealed edges and / or chamfers

Abstract

The invention relates to a composition for sealing and coating the edges and / or chamfers of artificial panels, comprising at least one expanding agent and at least one additive consisting of at least one compound of the general formula (I) R1 aSiX1 (4-a) (I) wherein X1 is an alkoxy, aryloxy, acyloxy group and R1 is an organic residue, r1 has at least one functional group Q1 selected from the group consisting of: alkyl, aryl, cycloalkyl, which may be broken by-O-or-NH-, and wherein R1 has at least one functional group Q1 selected from the group consisting of: acrylic, acryloyloxy, methacrylic, methacryloyloxy, cyano, isocyano and epoxy groups, and a = 0, 1, 2, 3, in particular 0 or 1; at least one compound of general formula (II) R2bSiX2 (4-b) (II) wherein X2 is an alkoxy group, an aryloxy group, an acyloxy group, R2 is a non-hydrolysable organic residue R2 selected from alkyl and aryl groups, and b = 1, 2, 3 or 4; and at least one aqueous polymer dispersion, and the composition comprises at least one surfactant.

Description

Technical Field

[0001] The present invention relates to a wood-based panel having coated and sealed edges and / or chamfers, wherein a composition for sealing and coating the edges and / or chamfers of the wood-based panel comprises a silane, an intumescent agent, and a surfactant. The present invention also relates to the preparation of the composition. Background Art

[0002] Floor panels with tongue-and-groove profiles on their side edges for laying into panel composite structures, such as laminate flooring, are widely used and conventionally known. The tongue-and-groove profile allows for simple laying of the floor panels into a flooring underlayment. This flooring underlayment can consist, for example, of wood fiberboard or plastic board. Floor panels are typically provided with a decorative layer and a wear-resistant surface layer.

[0003] This tongue-and-groove profile has a tongue (or tongue) on a first side edge, the tongue having a (first) joint surface arranged above the tongue, and a groove on a second side edge, the groove having a lip with a (second) joint surface. When the panels are laid, the tongue and groove are plugged or snapped into one another, so that the first and second joint surfaces come into contact. However, this solution creates gaps on the top sides of the joined panels, particularly at the points of contact between the joint surfaces of two opposing side edges of two joined floor panels, through which moisture and dust can penetrate between the floor panels.

[0004] In order to reduce the ingress of water at the contact points of the tongue-and-groove profiles, modern snap-fit profiles additionally have a bend in the region of the joint edge. A bend is understood to be a shoulder, edge or fold.

[0005] Laminate floors with so-called V-joints have proven to be very popular. These V-joints are formed with a chamfer when the floor panels are laid. The chamfers are inclined cutouts on the side edges of the floor panels, which are painted with a pigmented lacquer and give the laminate floor a visual impression that mimics a wooden floor.

[0006] However, all of these panel connection variants still only offer inadequate protection against water ingress at the connection or contact points. This is caused by the fact that in these products, water (e.g., during cleaning) is drawn into the profile area through fine joints or gaps between the floor panels via capillary forces, causing swelling there. To examine this problem, the so-called NALFA test was developed. In this test, a defined amount of water is applied to the connection area of three laid plank sections. After a defined testing time (24 hours), an analysis is performed to determine whether water is still present on the surface, whether water has penetrated into the profile, whether it has passed through the profile to the underside, and whether any visible swelling of the planks can be detected.

[0007] To date, various strategies have been used, either individually or in combination, to reduce moisture damage. The simplest approach to hindering moisture penetration into the profile is to achieve the tightest possible fit in the tongue-and-groove joint. However, this can make joining the elements difficult or lead to damage during installation. These methods also have the disadvantage that if water penetrates into the tongue-and-groove region, the wood-based carrier will naturally expand.

[0008] Another possibility is to seal the profile with a hydrophobic agent. WO 2006 / 038867 describes coating edges with wax, where at least partial penetration of the wax into the wood material has been observed. EP 903451 A2 discloses treating edges with diphenylmethane diisocyanate, which readily penetrates the wood material. WO 2008 / 078181 A1 again uses fluorinated polymers, such as perfluoroalkyl-methacrylic acid copolymers, as coating agents, where the layer-forming material is solid at room temperature.

[0009] A particular disadvantage of these known sealants is that they often migrate even when applied to the wood-based carrier, minimizing the hydrophobic effect. However, this can also occur later, so that the effect slowly disappears during use. Furthermore, perfluorinated compounds should be classified as critical from an environmental perspective.

[0010] Correspondingly, various disadvantages arise from the known measures: the improvement of the expansion protection is therefore too little, the proposed measures sometimes cannot withstand the actual requirements, and the resulting effect is limited in time. Summary of the Invention

[0011] The invention is therefore based on the object of overcoming the aforementioned disadvantages. In particular, the invention is based on the technical object of producing a laminate flooring based on wood-based panels, which creates a profile that is impermeable to surface water by means of sealed edges and chamfered areas.

[0012] According to the invention, this object is achieved by a wood-based panel having the features of claim 1 .

[0013] Accordingly, a wood-based panel, in particular a floor panel, having coated and sealed edges and / or chamfers is provided, wherein the composition for coating and sealing the edges and / or chamfers of the wood-based panel comprises:

[0014] a) at least one expanding agent, and d) at least one additive consisting of:

[0015] - at least one compound of formula (I)

[0016] R 1 a SiX 1 (4-a) (I), where

[0017] -X 1 is an alkoxy group, an aryloxy group, an acyloxy group, and

[0018] -R 1 is an organic residue selected from: an alkyl group, an aryl group, a cycloalkyl group, wherein the alkyl group, the aryl group, the cycloalkyl group may be disconnected by -O- or -NH-, and

[0019] -R 1 having at least one functional group Q1 selected from the group consisting of an acrylic group, an acryloxy group, a methacrylic group, a methacryloyloxy group, a cyano group, an isocyano group, and an epoxy group, and

[0020] - a = 0, 1, 2, 3, especially 0 or 1;

[0021] - at least one compound of formula (II)

[0022] R 2 b SiX 2 (4-b) (II), where

[0023] -X 2 is an alkoxy group, an aryloxy group, an acyloxy group, and

[0024] -R 2 is a non-hydrolyzable organic residue R 2 , which is selected from: alkyl and aryl, and

[0025] - b = 1, 2, 3 or 4, preferably 1 or 2; and

[0026] - at least one aqueous polymer dispersion, and

[0027] c) at least one surfactant, preferably at least one anionic surfactant.

[0028] The water repellency of the composition can be realized for a variety of locking profiles. The composition is especially applied to the profile surface, joint surface and / or chamfer of the side edge of the artificial board, especially the floor panel.

[0029] By adding the swelling agent, the composition not only has a water-repellent effect, but also causes the joint edges of the floor panels that are joined together to form a floating floor covering to be sealed, thereby further improving the sealing of the joints of the joined panels.

[0030] The additives used in the present composition comprise a crosslinking component in the case of compounds of the general formula (I) and a hydrophobic component in the case of compounds of the general formula (II). The crosslinking hydrophilic component of the formula (I) firstly enables the compound to bind to the wood fibers, in particular via free -OH groups (already present or formed by, for example, hydrolysis of alkoxy groups), and secondly enables the formation of a network. The hydrophobic component of the formula (II) - for example, consisting of the residue R 2 The alkyl groups of the ...

[0031] The additives used in this composition fill the pores present in the wood fiber board and coat the wood fibers, thereby "sealing" them. On the other hand, the "hydrophobicity" of the remaining pores and the not yet coated wood fibers is established by using a hydrophobic modifier.

[0032] To achieve the highest possible flexibility of the coating, the silane compound is mixed with a suitable aqueous polymer dispersion. The polymer used has functional groups that are compatible with the inorganic silane matrix. This allows the production of coatings with a high degree of crosslinking, even at low temperatures.

[0033] The surfactant used in the composition causes a reduction in the surface stress of the preferably aqueous composition and aids in forming a dispersion with the swelling agent, or acts as a co-solvent.

[0034] While WO 2020 / 016176 A1 discloses the use of compositions containing silanes and polymer dispersions, the compositions cited there contain neither swelling agents nor surfactants. As mentioned above, in addition to the water-repellent effect, the combined addition of swelling agents and surfactants also seals the joint edges of floor panels joined to form a floating floor underlayment, thereby improving the sealing of the joints between the joined panels compared to the compositions of WO 2020 / 016176 A1 (see also Example 4). The improved effects of the compositions according to the present invention are surprising and unforeseeable.

[0035] The present composition can be used in any board system and glue system. Consequently, regardless of the glue system used, the different porosities, or the board thickness, the composition reduces expansion in wood fiberboards. Thus, the expansion-reducing effect of the present composition can be demonstrated in HDF boards and particleboards with urea-formaldehyde glue (UF glue), melamine-urea-formaldehyde glue (MUF glue), or polyurethane-based glue (PMDI glue).

[0036] In one embodiment of the present composition, at least one swelling agent is selected from swellable natural or synthetic polymers or inorganic substances.

[0037] Thus, the at least one swelling agent may be a swellable polymer selected from: polysaccharides, preferably xanthan gum, starch, cellulose, modified cellulose, preferably ethylcellulose, pectin; proteins, preferably gelatin.

[0038] Xanthan gum is a naturally occurring polysaccharide that is obtained from sugar-containing substrates using bacteria of the genus Xanthomonas and is used in food, inter alia, as a thickener and gelling agent.

[0039] Ethylcellulose is a macromolecular substance obtained semisynthetically from naturally occurring cellulose. Chemically, it is a type of cellulose ether that is distinguished by its degree of polymerization (molar mass distribution) and its degree of etherification.

[0040] In one embodiment, the starch used is selected from potato starch, corn starch, wheat starch or rice starch.

[0041] Starch is a kind of starch composed of α-D-glucose units with the formula (C6H 10 O5) nPolysaccharides. Therefore, macromolecules are carbohydrates. Starch can physically combine with water several times its own weight under the action of heat, swell, and become sticky. When heated with water, starch swells at 47°C-57°C and produces starch paste at 55°C-87°C (potato starch at 62.5°C, wheat starch at 67.5°C). The starch paste has different solidification abilities depending on the type of starch (corn starch paste is greater than wheat starch paste, which is greater than potato starch paste) and is easily decomposed to a greater or lesser extent under acidification.

[0042] In another embodiment, the at least one swelling agent is a swellable synthetic polymer selected from the group consisting of polyacrylates or inorganic substances such as silica gel. In contrast, sheet silicates are not provided as swelling agents.

[0043] In a particularly preferred embodiment, a copolymer of acrylic acid and acrylic acid esters is used as the swelling agent. These acrylic acid-containing absorbents, which have a particle size between 100 μm and 1000 μm and are also known as superabsorbents, are capable of absorbing several times their own weight in polar liquids, such as water. When absorbing liquid, the superabsorbent swells and forms a hydrogel. In this case, the swelling agent, in a particularly preferred embodiment, is a copolymer of potassium polyacrylate and polyamide.

[0044] Particularly preferably used swelling agents are ethylcellulose, polyacrylates and / or xanthan gum.

[0045] The proportion of the at least one expansion agent, based on the additive, is between 0.3% by weight and 5% by weight, preferably between 1% by weight and 4% by weight.

[0046] Residue X 1 More advantageously selected from: C 1-6 - alkoxy, especially methoxy, ethoxy, n-propoxy and butoxy; C 6-10 - aryloxy, especially phenoxy; C 2-7 - acyloxy, in particular acetoxy or propionyloxy, and the residue X 2 Advantageously selected from: H; C 1-6 - alkoxy, especially methoxy, ethoxy, n-propoxy and butoxy; C 6-10 - aryloxy, especially phenoxy; C 2-7 - acyloxy, especially acetoxy or propionyloxy.

[0047] Organic residue R 1 Preferably selected from: C1-C 30 -alkyl, especially C5-C 25 In one embodiment, the organic R 1Selected from: methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, cyclohexyl, preferably selected from methyl, ethyl, propyl.

[0048] In one embodiment of the present composition, at least one functional group Q 1 is selected from: epoxy groups, methacrylic groups, methacryloyloxy groups, vinyl groups, cyano groups and / or isocyano groups. 1 It may be advantageous to have residues with double bonds or epoxy groups which can be activated and polymerized by means of UV radiation.

[0049] In one variation of the present composition, the functional group Q 1 According to the general formula (I) R 1 a SiX 1 (4-a) , especially R 1 SiX 1 The compound of 3 may be selected from: methacryloxypropyltrimethoxysilane (MPTS), silanes with epoxy functionality, such as glycidyloxypropyltriethoxysilane or silanes with vinyl functionality, such as vinyltrimethoxysilane.

[0050] As described, residue R 1 May have at least one functional group Q 1 .

[0051] However, in a preferred embodiment, it is provided that the radical R1 does not have one of the functional groups Q1 described, in particular no polymerizable groups such as double bonds or epoxy bonds.

[0052] But in addition, the residue R 1 It may be present in a substituted form with other residues.

[0053] The term "substituted" means that one or more atoms, typically H atoms, are replaced by one or more of the following substituents, preferably by one or two of the following substituents: hydroxy, protected hydroxy, oxo, protected oxo, C3-C7 cycloalkyl, bicycloalkyl, phenyl, naphthyl, amino, protected amino, monosubstituted amino, protected monosubstituted amino, disubstituted amino, guanidinyl, protected guanidinyl, heterocyclyl, substituted heterocyclyl, such as pyrrolidinyl, imidazolyl, indolyl, C1-C7 ... 12 -alkoxy, C1-C 12 -acyl, C1-C 12 -acyloxy, acryloyloxy, carboxyl, protected carboxyl, carbamoyl, cyano, methanesulfonylamino, thiol, C1-C10 -alkylthio and C1-C 10 - Alkylsulfonyl. The substituted alkyl group, aryl group, alkenyl group may be substituted once or more times with the same or different substituents, and preferably substituted once or twice.

[0054] As used herein, the term "aryl" refers to an aromatic hydrocarbon, such as phenyl, benzyl, naphthyl or anthracenyl. A substituted aryl group is an aryl group as defined above substituted with one or more substituents as defined above.

[0055] The term "cycloalkyl" includes the groups: cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and cycloheptyl.

[0056] In a particularly preferred variant of the present composition, the compound of the general formula (I) corresponds to the formula SiX 1 4, where residue X 1 is an alkoxy group, in particular a methoxy group, an ethoxy group, an n-propoxy group or an isopropoxy group. As particularly preferred crosslinking agents, tetramethoxysilane and tetraethoxysilane are used.

[0057] In another embodiment of the present composition, the non-hydrolyzable organic residue R of the compound according to formula (II) 2 Selected from: C1-C 15 -alkyl, especially C1-C 10 -alkyl and C6-C 10 -aryl. 15 -alkyl, especially C1-C 10 -alkyl and C6-C 10 -Aryl groups may be unsubstituted or may be substituted with another hydrophobic group.

[0058] Preferably, the non-hydrolyzable organic residue R 2 Selected from: methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, cyclohexyl, phenyl and naphthyl. Particularly preferred are methyl, ethyl, propyl, octyl or phenyl residues.

[0059] Within the scope of the present invention, the term “non-hydrolyzable organic residue” is understood to mean an organic residue which, in the presence of water, does not lead to the formation of OH groups or NH 2 groups bonded to Si atoms.

[0060] The compound of formula (II) may in particular comprise one of the following formulae:

[0061] -R 2 SiX 2 3, where R 2As a C1-C10 alkyl group, preferably methyl, ethyl, propyl, pentyl, hexyl, heptyl, octyl, or as a C6-C10 aryl group, preferably phenyl, and wherein X 2 As alkoxy groups, in particular methoxy, ethoxy, n-propoxy or isopropoxy groups are mentioned, for example methyltriethoxysilane, octyltriethoxysilane, phenyltriethoxysilane.

[0062] In one variant of the present composition, the compound of the general formula (I) and the compound of the general formula (II) are used separately as additives.

[0063] However, in another embodiment of the present composition, the additive may also contain at least one compound of the general formula (I) and at least two, preferably at least three, compounds of the general formula (II). Any combination is conceivable. However, in a preferred embodiment, no more than four silane compounds are contained in the composition.

[0064] Therefore, the additives used in the present composition may have the following combinations:

[0065] -At least one SiX 1 4, where residue X 1 is alkoxy, especially methoxy, ethoxy, n-propoxy or isopropoxy; and at least one R 2 SiX 2 3, where R 2 As a C1-C10 alkyl group, preferably methyl, ethyl, propyl, pentyl, hexyl, heptyl, octyl, or as a C6-C10 aryl group, preferably phenyl, and wherein X 2 As alkoxy, in particular methoxy, ethoxy, n-propoxy or isopropoxy, for example methyltriethoxysilane, octyltriethoxysilane, phenyltriethoxysilane; or

[0066] -At least one SiX 1 4, where residue X 1 is alkoxy, especially methoxy, ethoxy, n-propoxy or isopropoxy; and at least one R 2 SiX 2 3, where R 2 As C1-C10 alkyl groups, preferably methyl, ethyl, propyl, pentyl, hexyl, heptyl, octyl, for example methyltriethoxysilane, octyltriethoxysilane; and at least one R 2 SiX 2 3, where R 2 As the C6-C10 aryl group, phenyl is preferred, and wherein X 2 As alkoxy, in particular methoxy, ethoxy, n-propoxy or isopropoxy, for example phenyltriethoxysilane, or

[0067] -At least one SiX 1 4, where residue X 1 is alkoxy, especially methoxy, ethoxy, n-propoxy or isopropoxy; and at least two R 2 SiX 2 3, where R 2 As C1-C10 alkyl groups, preferably methyl, ethyl, propyl, pentyl, hexyl, heptyl, octyl, for example methyltriethoxysilane, octyltriethoxysilane; and at least one R 2 SiX 2 3, where R 2 As the C6-C10 aryl group, phenyl is preferred, and wherein X 2 As alkoxy, in particular methoxy, ethoxy, n-propoxy or isopropoxy, for example phenyltriethoxysilane.

[0068] Furthermore, in one variant, the composition may comprise tetraethoxysilane as the compound of formula (I) and methyltriethoxysilane and phenyltriethoxysilane as the compounds of formula (II).

[0069] In another variant, the composition can comprise tetraethoxysilane as the compound of formula (I) and methyltriethoxysilane, phenyltriethoxysilane and octyltriethoxysilane as the compound of formula (II).

[0070] In another embodiment, the compound of the general formula (I) is contained in the composition in a molar amount of between 0.08 mol and 0.2 mol, preferably between 0.1 mol and 0.15 mol, particularly preferably between 0.1 mol and 0.12 mol, and the compound of the general formula (II) is contained in a molar amount of between 0.05 mol and 0.1 mol, preferably between 0.06 mol and 0.09 mol, particularly preferably between 0.07 mol and 0.08 mol.

[0071] The molar amount ranges given here for the compounds of the general formula (II) can relate to one compound of the general formula (II) or to the sum of two or three compounds of the general formula (II).

[0072] Thus, in a variant of the composition composed of tetraethoxysilane as compound of formula (I) and methyltriethoxysilane and phenyltriethoxysilane as compounds of formula (II), 0.15 mol of tetraethoxysilane and 0.04 mol of methyltriethoxysilane / 0.033 mol of phenyltriethoxysilane may be included.

[0073] In another variant of the composition consisting of tetraethoxysilane as the compound of formula (I) and methyltriethoxysilane, phenyltriethoxysilane and octyltriethoxysilane as the compounds of formula (II), 0.1 mol of tetraethoxysilane and 0.03 mol of methyltriethoxysilane, 0.025 mol of phenyltriethoxysilane and 0.043 mol of octyltriethoxysilane can be contained.

[0074] The ratio of the silane compound of the formula (I) to the silane compound of the formula (II) is preferably between 1:0.5 and 1:2, particularly preferably between 1:0.75 and 1:1.5, very particularly preferably between 1:1 and 1:1.2.

[0075] In a further embodiment of the present composition, the at least one polymer is selected from: polyurethanes; epoxy resins; melamine resins, such as melamine formaldehyde resins; and polyacrylates.

[0076] Currently preferred is the use of polyurethane polymers, wherein the polyurethane polymer is based on aromatic polyisocyanates, in particular polydiphenylmethane diisocyanate (PMDI), toluene diisocyanate (TDI) and / or diphenylmethane diisocyanate (MDI), PMDI being particularly preferred.

[0077] The polymer is built into the network formed by the silane compound and imparts flexible properties to the composition that allow for easy coating.

[0078] The type of polymer used is preferably coordinated with the silane compound used. Thus, it is advantageous to use silanes modified with epoxy groups with epoxy polymers and silanes modified with methacrylate groups with acrylate polymers.

[0079] In another embodiment of the present composition, it is also possible to use more than one polymer.

[0080] In another embodiment, the polymer content in the composition used is at least 30% by weight, preferably at least 20% by weight, particularly preferably at least 10% by weight. In one embodiment, the sol-gel to polymer ratio is between 1:0.1 and 1:0.5, preferably between 1:0.2 and 1:0.4 (based on solids).

[0081] The solvent content, essentially resulting from the use of silanes, is between 1% and 15% by weight, preferably between 2% and 13% by weight, and particularly preferably between 4% and 10% by weight. However, this description does not initially take into account the solvent content of the polymer used. The solvent is, in particular, water and / or alcohol, preferably ethanol. The alcohol content can, for example, be <1%. It is also possible for the composition to contain only alcohol and a small amount of water, or no water at all, meaning that the silane compound and the polymer dispersion can be used in alcoholic form.

[0082] In another embodiment, the present composition may contain inorganic particles, in particular SiO2 particles, Al2O3 particles, ZrO2 particles, TiO2 particles. The particles preferably used here have a size between 2 nm and 400 nm, preferably between 2 nm and 100 nm, and particularly preferably between 2 nm and 50 nm. By adding inorganic particles, the solid content of the composition is increased, thereby improving the coating performance of the composition. By adding inorganic particles, shrinkage and crack formation are also prevented. Inorganic particles are used in an amount ranging from 0.1 wt. % to 25 wt. %, preferably from 5 wt. % to 20 wt. %, based on the solid content of the silane material (sol-gel material).

[0083] Therefore, the additives used in the present composition may have the following combinations:

[0084] -At least one SiX 1 4, where residue X 1 is alkoxy, especially methoxy, ethoxy, n-propoxy or isopropoxy; and at least one R 2 SiX 2 3, where R 2 As a C1-C10 alkyl group, preferably methyl, ethyl, propyl, pentyl, hexyl, heptyl, octyl, or as a C6-C10 aryl group, preferably phenyl, and wherein X 2 As alkoxy groups, in particular methoxy, ethoxy, n-propoxy or isopropoxy groups, for example methyltriethoxysilane, octyltriethoxysilane, phenyltriethoxysilane, polyurethanes and optionally SiO 2 particles; or

[0085] -At least one SiX 1 4, where residue X 1 is alkoxy, especially methoxy, ethoxy, n-propoxy or isopropoxy; and at least one R 2 SiX 2 3, where R 2 As C1-C10 alkyl groups, preferably methyl, ethyl, propyl, pentyl, hexyl, heptyl, octyl, for example methyltriethoxysilane, octyltriethoxysilane; and at least one R 2 SiX 23, where R 2 As the C6-C10 aryl group, phenyl is preferred, and wherein X 2 as alkoxy groups, in particular methoxy, ethoxy, n-propoxy or isopropoxy groups, for example phenyltriethoxysilane, polyurethanes and optionally SiO2 particles, or

[0086] -At least one SiX 1 4, where residue X 1 is alkoxy, especially methoxy, ethoxy, n-propoxy or isopropoxy; and at least two R 2 SiX 2 3, where R 2 As C1-C10 alkyl groups, preferably methyl, ethyl, propyl, pentyl, hexyl, heptyl, octyl, for example methyltriethoxysilane, octyltriethoxysilane; and at least one R 2 SiX 2 3, where R 2 As the C6-C10 aryl group, phenyl is preferred, and wherein X 2 As alkoxy groups, in particular methoxy, ethoxy, n-propoxy or isopropoxy groups are used, for example phenyltriethoxysilane, polyurethanes and optionally SiO 2 particles.

[0087] A particularly preferred variant of the present composition comprises tetraethoxysilane, methyltriethoxysilane, phenyltriethoxysilane, octyltriethoxysilane and polyurethane and optionally SiO particles. A more particularly preferred variant of the present composition comprises tetraethoxysilane, methyltriethoxysilane, phenyltriethoxysilane, octyltriethoxysilane, polyurethane and SiO particles.

[0088] As mentioned above, according to the invention, the composition comprises at least one surfactant. The surfactant reduces the surface stress of the preferably aqueous composition and assists in forming a dispersion with the swelling agent or acts as a cosolvent.

[0089] Possible surfactants are anionic and cationic surfactants based on quaternary ammonium compounds.

[0090] As anionic surfactants, alkyl carboxylates, alkylbenzenesulfonates, preferably sodium dodecylbenzenesulfonate, secondary alkylsulfonates, fatty alcohol sulfates, such as sodium lauryl sulfate, or alkyl ether sulfates, such as sodium dodecylpoly(oxyethylene)sulfate, can be used. Preferably, sodium dodecylbenzenesulfonate is used.

[0091] The amount of surfactant added is between 0.1% and 0.2% by weight, preferably between 0.12% and 0.15% by weight, based on the additive consisting of silane and polymer.

[0092] The described composition comprising at least one swelling agent, at least one additive consisting of at least two silanes and a polymer (as described above) and at least one surfactant is used for coating and sealing profiles, upper areas of joint edges and / or chamfers (for V-joints).

[0093] The composition for coating and sealing the edges and / or chamfers of the wood-based panels and applied accordingly to the edges and / or chamfers of the wood-based panels preferably does not contain chromium-containing compounds that are classified as being of concern from a health perspective. Furthermore, the composition preferably does not contain zinc-containing and / or halogen-containing, in particular chlorine-containing, substances.

[0094] In another embodiment, at least one chamfered pigment system is added to the present composition. The chamfered pigment system comprises a color pigment and an aqueous solvent or suspending agent. Carbon black, iron oxide, titanium dioxide, and / or an organic colorant are used as the color pigment. Suitable solvents or suspending agents are melamine resin, formaldehyde resin, or acrylate. In one embodiment, the chamfered pigment comprises a color pigment, an acrylate, and water.

[0095] Accordingly, a coating system or sealing system is also provided, comprising at least one swelling agent, at least one additive consisting of at least two silanes and a polymer as described above, at least one surfactant, at least one chamfering pigment, and a suspending agent, preferably an aqueous acrylate. The coating system is preferably used for coating and sealing joint edges and / or chamfers (for V-joints).

[0096] According to a first embodiment, the present composition can be prepared in a method comprising the following steps:

[0097] - providing at least one dispersion A) comprising a polymer dispersion and optionally a dispersion of inorganic particles,

[0098] providing a solution B) comprising a mixture of at least one compound of the general formula (I), at least one compound of the general formula (II) and at least one catalyst, in particular an acid,

[0099] - adding solution B) to dispersion A) and neutralizing the added mixture (for example by adding a basic compound);

[0100] - separating the aqueous phase of the additive consisting of the polymer dispersion, the at least one compound of formula (I) and the at least one compound of formula (II), and

[0101] - adding at least one surfactant to the aqueous additive phase,

[0102] - adding at least one swelling agent to the aqueous additive phase,

[0103] - Optionally, at least one chamfered pigment system is added.

[0104] Suitable inorganic and / or organic acids as catalysts are selected from the group consisting of phosphoric acid, acetic acid, p-toluenesulfonic acid, hydrochloric acid, formic acid or sulfuric acid. Also suitable are ammonium salts, such as ammonium sulfate, which react as weak acids. p-Toluenesulfonic acid is particularly preferred.

[0105] To subsequently neutralize the reaction mixture, a basic compound, such as ammonia or NaOH, is preferably added. This causes the aqueous phase with the binder content to separate from the alcoholic phase (ethanol phase). The aqueous phase can then be easily separated from the alcoholic phase.

[0106] When inorganic particles are mixed into the adhesive composition, the inorganic particles are preferably used in an amount of between 0.1% and 15% by weight, preferably between 0.5% and 10% by weight, particularly preferably between 1% and 5% by weight.

[0107] The addition of at least one surfactant enables better suspension of the subsequently added swelling agent, as described above.

[0108] Depending on the swelling agent added, an increase in viscosity occurs. This increase in viscosity is influenced by the swelling agent used and can lead to undesirable gel formation, thereby impairing the further use of the composition.

[0109] The viscosity of the composition was determined during the outflow time using a flow cup in accordance with EN ISO 2431:2011 (coating material—determination of the outflow time using a flow cup, 4 mm nozzle, 21° C.).

[0110] The composition comprising at least one surfactant has an outflow time of between 10 and 60 seconds, preferably between 12 and 40 seconds, more preferably between 15 and 30 seconds. In the absence of a surfactant, the composition has an outflow time of greater than 60 seconds.

[0111] When using xanthan gum as a swelling agent, it has proven advantageous, for example, to first provide a mixture having the general formula R 2 SiX 2 3. An aqueous xanthan gum solution of at least one silane, wherein R 2 As the C1-C10 alkyl group, preferably methyl, ethyl, propyl, pentyl, hexyl, heptyl, octyl, and wherein X 2 As alkoxy groups, in particular methoxy, ethoxy, n-propoxy or isopropoxy groups are used, for example methyltriethoxysilane. The addition of silanes prevents gel formation in the xanthan gum.

[0112] In a further step, a composition comprising at least one swelling agent, at least one additive consisting of at least two silanes and a polymer (as described above), and at least one surfactant can be added to the chamfered pigment system (consisting of the chamfered pigment and the suspending agent). The amount added to the chamfered pigment system can be up to 20% by weight, preferably up to 30% by weight, particularly preferably up to 40% by weight, and even more preferably up to 50% by weight.

[0113] As already mentioned above, the composition can be used for coating or sealing joint edges, profiles and / or chamfers of wood-based panels, in particular WPC, particleboards, HDF boards or MDF boards.

[0114] Preferably, the wood-based panels coated and sealed with the described composition are HDF boards or MDF boards or particle boards, wherein the joint edges, profiles and / or chamfers of the wood-based panels are coated for sealing purposes.

[0115] The composition can be applied, for example, to the joint edges, profiles and / or chamfers of the wood-based panels by spraying, rolling or using a vacuum clamp.

[0116] The layer thickness of the composition on the pane edge and / or pane chamfer can be between 10 μm and 50 μm, preferably between 20 μm and 40 μm.

[0117] The composition can be applied in liquid form at a density of 100 g / m 2 and 200g / m 2 Liquid silane between 120g / m 2 and 150g / m 2 An amount of liquid silane between 5 mg / cm2 is applied to the panel edge and / or chamfer. This results in a volumetric silane concentration of 5 mg / cm2 on the panel edge. 2 and 25 mg / cm 2 between, preferably between 10 mg / cm 2 and 20 mg / cm 2 The solid share between.

[0118] Wood-based panels, such as particleboards and fiberboards, for example MDF and HDF, are manufactured from wood chips or wood fibers obtained by chipping wood in a chipper or by fiber separation in a refiner. The wood fibers used in fiberboards have a length between 1.5 mm and 20 mm and a thickness between 0.05 mm and 1 mm. The size of the wood chips used in particleboards depends on whether they are used in the top or middle layer. In the middle layer, the chip screening width is >0.125 mm, and in the top layer, the chip screening width is >0.8 mm to 1.0 mm.

[0119] The wood-based panels can have various binder systems, which are mixed with the wood fibers as a binder and compacted. Preferred binder systems are: formaldehyde resins, such as urea-formaldehyde resins, melamine-formaldehyde resins, melamine-urea-formaldehyde resins; polyurethanes, preferably based on polydiphenylmethane diisocyanate (PMDI); epoxy resins or polyester resins.

[0120] The wood-based panels can also have a coating on the upper side of the panel comprising a film, for example a film made of thermoplastics such as PVC or PP, or a paper impregnation, for example an impregnation consisting of a decorative paper layer or cover paper. Covering layer impregnations, decorative impregnations, balancing impregnations, and kraft paper impregnations are based on a thin paper layer that is completely or partially impregnated (impregnated) with a resin, preferably a melamine-formaldehyde resin.

[0121] The impregnation can be applied, for example, in an impregnation tank by roller coating, anilox roller coating, doctor blade coating, or even by spraying. In one embodiment, the paper layer is treated as follows: the back side of the paper layer is first impregnated with a resin having a solids content of between 50% and 70% by weight, preferably 60% by weight, in an impregnation tank. After a breathing zone, the resin is immersed in the impregnation. Excess resin is removed in a doctor blade system / pressure roller pair, and wear-resistant particles are optionally sprinkled onto the impregnated paper layer (in the case of a covered paper layer). A drying step is carried out to a residual moisture content of approximately 6%.

[0122] In the case of coated wood-based panels, the paper (decorative paper, overlay paper) is placed on the wood-based panel and pressed. Typically, the impregnated decorative paper is first applied to the top of the wood-based panel. Subsequently, at least one covering impregnation is applied to the decorative impregnation. A balancing impregnation is pressed against the wood-based panel from the bottom. The typical structure of a coated HDF board, from top to bottom, is: covering impregnation, decorative impregnation, HDF carrier, balancing impregnation.

[0123] In one embodiment, it is also proposed to apply a veneer to the wood-based panel. Such veneers usually have a surface treatment consisting of a UV or ESH lacquer-based paint.

[0124] The veneer is glued to the wood-based panel (HDF, particle board, OSB, etc.). In order to glue the veneer to the carrier, urea glue or PVAc glue with or without curing agent is usually used.

[0125] It is also possible to press the veneer onto the artificial board in a short-cycle press using paper (e.g., a covering layer) impregnated with melamine resin. The pressing parameters are approximately T>150°C, p>30 bar, and t>30 seconds. With the aid of this technology, it is also possible to produce veneer floors with a thickness of approximately 0.5 mm. What is crucial here is that during the pressing process, the melamine resin also rises as far as possible into the veneer. Thus, on the one hand, the veneer is reinforced with the help of the artificial resin, and on the other hand, the veneer compressed by the pressing is fixed in this state. However, the melamine resin should not overflow from the veneer, as this causes discoloration of the surface and causes adhesion problems during subsequent painting or oiling.

[0126] In a preferred embodiment, particleboard is used that is pressed against a veneer. To this end, in a first step, resin-impregnated paper (preferably resin-impregnated kraft paper) with the veneer is placed on the particleboard (e.g., on the top side) and pressed. In further variations, resin-impregnated paper and / or veneer are used as a balancing element.

[0127] It is also possible to coat the artificial board with a liquid resin layer (liquid coating) and compact it. Here, a base coat is first applied to the artificial board, followed by a primer layer, which is then printed to form the decorative layer. Subsequently, another resin layer is applied to the decorative layer as a protective and wear-resistant layer. Accordingly, the artificial board can have at least one decorative layer on the top side and a multi-layer resin structure containing wear-resistant particles, cellulose fibers, and glass beads. The following layer structure is possible (viewed from bottom to top): a balancing part consisting of six resin layers - artificial board - base coat - printed decorative layer - protective layer, in particular a protective layer consisting of resin that has not yet fully solidified - a first resin layer containing cellulose fibers - a layer consisting of wear-resistant particles - a second resin layer - a third resin layer containing glass beads - a fourth resin layer containing glass beads - a fifth resin layer containing glass beads - a sixth resin layer (without glass beads). The protective layer is used to cover the decorative object and protect it during temporary storage (stacking, storage, transportation). The further resin layers on the upper side together form a covering layer which protects the finished laminate from wear and enables a structuring that is simultaneously decorative.

[0128] When using the described wood-based panels as floor panels, the panels are provided with tongue-and-groove locking mechanisms and are intended for floating installation. The corresponding installation method comprises laying a first floor panel and joining a second floor panel to the first, wherein the tongue of the second floor panel engages with the groove of the first floor panel.

[0129] After installation, the floor panels provided with the chamfers form a V-joint which is sealed and protected against the penetration of moisture by the applied composition of chamfer pigment and additives.

[0130] The present invention will be described in detail below with reference to examples. DETAILED DESCRIPTION

[0131] Example 1: Preparation of a sealing composition according to the first embodiment

[0132] Provide 28.8 g of aqueous SiO2 dispersion ( 3550) and 20 g of aqueous polyurethane solution Alberdingk U 3215.

[0133] Simultaneously, 12.3 g of octyltriethoxysilane, 2.4 g of methyltriethoxysilane / triethoxy(methyl)silane or 6.1 g of phenyltriethoxysilane, 20.8 g of tetraethoxysilane, and 28.8 g of water were heated to 50°C and stirred. 2.8 g of sulfuric acid was then stirred for 120 minutes. This solution was then stirred into the suspension while still hot and stirring continued for 60 minutes at room temperature. 0.1 molar NaOH solution was added until a pH of 7.5 was reached.

[0134] After a rest period of 24 hours, the alcoholic phase was separated off via a separatory funnel. 0.13 g of the surfactant sodium dodecylbenzenesulfonate was subsequently added.

[0135] A swelling agent is now added to the solution, which is prepared as follows:

[0136] 10 g of xanthan gum were dissolved in 100 g of demineralized water, the solution was heated to 80° C. after 30 minutes, and 0.78 g of methyltriethoxysilane was added and stirring was continued for 60 minutes.

[0137] 20.1 g of aqueous xanthan gum solution are now added to 100 g of the above solution. If pure xanthan gum is added at this concentration, the solution thickens strongly and forms a gel.

[0138] Additives ( sil AS-II) is added to commercial edge coating systems up to 50% by weight, and the additive remains stable over several weeks. Curing after coating is carried out thermally (eg 100° C., 5 minutes).

[0139] Example 2: Preparation of a sealing composition according to the second embodiment

[0140] Provide 28.8 g of aqueous SiO2 dispersion ( 3550) and 20 g of aqueous polyurethane solution Alberdingk U 3215.

[0141] Simultaneously, 12.3 g of octyltriethoxysilane, 2.4 g of methyltriethoxysilane, 6.1 g of phenyltriethoxysilane, 20.8 g of tetraethoxysilane, and 28.8 g of water were heated to 50°C and stirred. 2.8 g of sulfuric acid was then stirred for 120 minutes. This solution was then stirred into the suspension while still hot and stirring continued for 60 minutes at room temperature. 0.1 molar NaOH solution was added until a pH of 7.5 was reached.

[0142] After a rest period of 24 hours, the alcoholic phase was separated off via a separatory funnel. 0.13 g of the surfactant sodium dodecylbenzenesulfonate was subsequently added.

[0143] 1.5 g of ethylcellulose are now added as a swelling agent to 100 g of the above solution. A slight increase in viscosity now occurs.

[0144] Additives ( sil AS-I) is added to commercial edge coating systems up to 50% by weight, and the additive remains stable over several weeks. Curing after coating is carried out thermally (eg 100° C., 5 minutes).

[0145] Example 3: Preparation of a sealing composition according to the third embodiment

[0146] Provide 28.8 g of aqueous SiO2 dispersion ( 3550) and 20 g of aqueous polyurethane solution Alberdingk U 3215.

[0147] Simultaneously, 12.3 g of octyltriethoxysilane, 2.4 g of methyltriethoxysilane, 6.1 g of phenyltriethoxysilane, 20.8 g of tetraethoxysilane, and 28.8 g of water were heated to 50°C and stirred. 2.8 g of sulfuric acid was then stirred for 120 minutes. This solution was then stirred into the suspension while still hot and stirring continued for 60 minutes at room temperature. 0.1 molar NaOH solution was added until a pH of 7.5 was reached.

[0148] After a rest period of 24 hours, the alcoholic phase was separated off via a separatory funnel. 0.13 g of the surfactant sodium dodecylbenzenesulfonate was subsequently added.

[0149] Now, 0.8 g of a polyacrylate-based superabsorbent is added as a swelling agent to 100 g of the above solution. Even with this small amount, a clear increase in viscosity occurs.

[0150] Additives ( sil AS-III) is added to commercial edge coating systems up to 50% by weight, and the additive remains stable over several weeks. Curing after coating is carried out thermally (eg 100° C., 5 minutes).

[0151] Example 4: NALFA test on samples with edge seals

[0152] The NALFA test was performed according to ISO 4760 EN. For this purpose, the composition of Example 1 was compared with the composition of WO 2020 / 01676 A1.

[0153] Control composition in WO 2020 / 01676A1:

[0154] 12.3 g of octyltriethoxysilane, 2.4 g of trimethylsilane, 6.1 g of phenyltriethoxysilane, 20.8 g of tetraethoxysilane, and 28.8 g of an aqueous SiO dispersion (50% by weight) from Obermaier are provided, heated to 80° C. and stirred. 3.6 g of p-toluic acid are then added to the water (30% by weight) with stirring and stirred for 120 minutes. After a further 24 hours, the pH is now raised to pH 7 by adding 25% ammonia solution (6.2 g in the above example) with stirring.

[0155] After a further stirring time of 2 hours, 80 g of water were now added, stirring was continued for 30 minutes, and the suspension was subsequently stored without stirring for 4 hours.

[0156] After the waiting time, the aqueous phase with the binder content is separated from the ethanol phase. The aqueous phase is now separated via a separating funnel. Thus, an inorganic aqueous coating system is obtained.

[0157] 50 g of the coating system (solids: 52%) were now mixed with 20 g of an aqueous polyurethane solution (U 3251 from Alberdingk, solids: 35%).

[0158] The coating system can now be applied to the edge by means of a foam roller or a pipette and thermally cured (eg 100° C. for 5 minutes).

[0159] The results of the NALF tests are listed in the table below.

[0160] Sample name NALFA test results %pass Comparative Example according to WO2020016176A1 55 Example 1 100

[0161] As can be seen from the table, the percentage of those that passed the NALFA test was almost doubled when the composition of Example 1 was used compared to the composition known from WO 2020016176 A1. Correspondingly, the sealing of the joints of the joined floor panels was improved with the composition of Example 1.

Claims

1. A wood-based panel comprising at least one composition, said composition being applied to the edges and / or chamfers of said wood-based panel, said composition being used for sealing and coating said edges and / or chamfers, wherein said composition comprises: a) at least one swelling agent, d) at least one additive consisting of: - at least one compound of formula (I) R 1 a SiX 1 (4-a) (I), where -X 1 is an alkoxy group, an aryloxy group, an acyloxy group, and -R 1 is an organic residue selected from: an alkyl group, an aryl group, a cycloalkyl group, wherein the alkyl group, the aryl group, the cycloalkyl group can be disconnected by -O- or -NH-, and -R 1 having at least one functional group Q1 selected from the group consisting of an acrylic group, an acryloxy group, a methacrylic group, a methacryloyloxy group, a cyano group, an isocyano group, and an epoxy group, and - a = 0, 1, 2, 3, especially 0 or 1; - at least one compound of formula (II) R 2 b SiX 2 (4-b) (II), where -X 2 is an alkoxy group, an aryloxy group, an acyloxy group, -R 2 is a non-hydrolyzable organic residue R 2 , which is selected from: alkyl and aryl, and - b = 1, 2, 3, or 4; and - at least one aqueous polymer dispersion, and c) at least one surfactant, preferably at least one anionic surfactant.

2. The artificial board having the composition according to claim 1, characterized in that The at least one swelling agent is a swellable polymer selected from the group consisting of: polysaccharides, preferably xanthan gum, starch, cellulose, modified cellulose, pectin; proteins, preferably gelatin.

3. The wood-based panel having the composition according to any one of the preceding claims, characterized in that The at least one swelling agent is a swellable synthetic polymer selected from the group consisting of: polyacrylates or silicones.

4. The wood-based panel having the composition according to any one of the preceding claims, characterized in that The proportion of the at least one expansion agent, based on the additive, is between 0.3% and 5% by weight.

5. The wood-based panel having the composition according to any one of the preceding claims, characterized in that The at least one anionic surfactant is selected from alkyl carboxylates, alkylbenzenesulfonates, preferably sodium dodecylbenzenesulfonate, secondary alkylsulfonates, fatty alcohol sulfates, such as sodium lauryl sulfate, or alkyl ether sulfates, such as sodium dodecylpoly(oxyethylene)sulfate.

6. The wood-based panel comprising the composition according to any one of the preceding claims, characterized in that At least one chamfered edge pigment system is added.

7. The wood-based panel having the composition according to any one of the preceding claims, characterized in that It comprises at least one compound of the general formula (I) and at least two, preferably at least three compounds of the general formula (II).

8. The wood-based panel comprising the composition according to any one of the preceding claims, characterized in that X 1 Selected from: C 1-6 - alkoxy, especially methoxy, ethoxy, n-propoxy and butoxy; C 6-10 - aryloxy, especially phenoxy; C 2-7 - acyloxy, especially acetoxy or propionyloxy; and X 2 Selected from: H; C 1-6 - alkoxy, especially methoxy, ethoxy, n-propoxy and butoxy; C 6-10 - aryloxy, especially phenoxy; C 2-7 - acyloxy, especially acetoxy or propionyloxy.

9. The wood-based panel comprising the composition according to any one of the preceding claims, characterized in that The compound of general formula (I) corresponds to the formula SiX 1 4, especially X 1 is alkoxy, especially methoxy, ethoxy, n-propoxy or isopropoxy.

10. The wood-based panel comprising the composition according to any one of the preceding claims, characterized in that The non-hydrolyzable organic residue R 2 Selected from: C1-C 15 -alkyl, especially C1-C 10 -alkyl; and C6-C 10 - aryl, preferably methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl, cyclohexyl, phenyl and naphthyl.

11. The wood-based panel comprising the composition according to any one of the preceding claims, characterized in that The compounds of formula (II) include one of the following: -R 2 SiX 2 3, where R 2 As a C1-C10-alkyl group, preferably methyl, ethyl, propyl, pentyl, hexyl, heptyl, octyl, or as a C6-C10-aryl group, preferably phenyl, and wherein X 2 As alkoxy, in particular methoxy, ethoxy, n-propoxy or isopropoxy.

12. The wood-based panel comprising the composition according to any one of the preceding claims, characterized in that The at least one polymer of the polymer dispersion is selected from the group consisting of polyurethanes, in particular polydiphenylmethane diisocyanate (PMDI); epoxy resins; melamine resins; and polyacrylates.

13. The wood-based panel comprising the composition according to any one of the preceding claims, characterized in that It can contain inorganic particles, in particular SiO2 particles, Al2O3 particles, ZrO2 particles, TiO2 particles.

14. A method for preparing a composition for sealing and coating edges and / or chamfers of a wood-based panel according to any one of the preceding claims, comprising the following steps: - providing at least one dispersion A) comprising a polymer dispersion and optionally a dispersion of inorganic particles, providing a solution B) comprising a mixture of at least one compound of the general formula (I), at least one compound of the general formula (II) and at least one catalyst, in particular an acid, - adding the solution B) to the dispersion A) and neutralizing the added mixture, preferably adding a basic compound; - separation of the aqueous phase of the additive consisting of the polymer dispersion, the at least one compound of formula (I) and the at least one compound of formula (II), - adding at least one surfactant, and - adding at least one swelling agent to the aqueous additive phase, - Optionally, at least one chamfered pigment system is added.