DE102006019819A1 - Aqueous, hardenable composition, useful for impregnating lignocellulose material e.g. wood and timber material, comprises low-molecular compound, oligo-/polyalkylenetherpolyol and reaction product of compound and polyalkylenetherpolyol - Google Patents

Abstract

Aqueous, hardenable composition comprises: at least one low-molecular weight compound containing at least two N-bonded groups of ethanol and/or two nitrogen atom of 1,2-bishydroxyethane-1,2-diyl-group; at least one oligo- or polyalkylenetherpolyol with at least two hydroxyl groups/molecule containing at least one bivalent or polyvalent aliphatic or cycloaliphatic group with 3C atom; and/or a reaction product of the low-molecular weight compound with the polyalkylenetherpolyol. Independent claims are included for: (1) a method for treating a lignocellulose material comprising impregnating the lignocellulose material in the composition and cross-linking at high temperature; and (2) the lignocelluclose material that is obtained by the above procedure.

Description

The present invention relates to aqueous, curable compositions for impregnating lignocellulosic materials which contain at least one low molecular weight compound V which contains at least two N-bonded groups of the formula CH ₂ OH and / or a 1,2-bishydroxyethane-1,2-one bridging two nitrogen atoms. having diyl group. The invention also relates to a process for impregnating lignocellulosic materials, in particular wood, using such compositions and the lignocellulosic materials thus obtainable.

One central problem with lignocellulosic materials such as wood and wood-based Materials is their common only moderate to low resistance on exposure to moisture. This results from the property of lignocellulosic materials, on contact with water or in moist The atmosphere, To store water. This causes the materials to swell and change their shape tend to crack or lose in the case of solid wood, in the case of moldings based on finely divided lignocellulosic materials, their mechanical Strength In addition, lignocellulosic materials, in particular when wet, from wood-degrading or wood-discoloring Organisms, especially microorganisms, infest what the equipment of this Materials with appropriate fungicides and biocides necessary power. This again represents a not inconsiderable cost factor and is also environmentally disadvantageous.

to Improvement in durability are wood and comparable lignocellulose-based Materials often hydrophobed, e.g. by treatment with wax-containing impregnants. This will cause water to enter the pores of the material difficult.

It was proposed the dimensional stability of wood and wood-based materials such as particleboard and fiberboard and their resistance to wood-destroying organisms by the acetylation of the wood particles with the help of anhydrides, such as acetic anhydride to improve (see EP-A 213252 and cited therein literature and Rowell et al., Wood and Fiber Science, 21 (1), pp. 67-79). adversely are the high cost of the treatment and the unpleasant odor of the material so treated, so that these measures have not prevailed in the market.

Out the publication "Treatment of timber with water soluble dimethylol stability and durability ", published in Wood Science and Technology 1993, pages 347-355 it is known to improve shrinkage and swelling properties of wood as well as the resistance to fungi and insects this with an impregnating agent to treat that from an aqueous solution Dimethyloldihydroxyethyleneurea (DMDHEU or 1,3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidinone-2) and a catalyst. At elevated temperature finds one Reaction of the DMDHEU with itself and the wood instead. To this Way became wooden body with dimensions of 20 mm × 20 mm × 10 mm examined. The method described can be only with small dimensions the wooden body Apply because these are larger in size tend to crack.

Out SE-C 500 039 is a method of hardening wood under compaction described in the untreated wood with various Aminoplastmonomeren based on melamine and formaldehyde by vacuum pressure impregnation impregnated, subsequently dried and in a press under compression at elevated temperature hardened become. As crosslinkers, inter alia, DMDHEU, dimethylolurea, Dimethoxymethylurea, dimethylolethyleneurea, dimethylolpropyleneurea and dimethoxydimethylurea. This procedure has the Disadvantage that the natural Wood structure is lost due to the compaction as well as the formaldehyde emission of the finished wood body is relatively high depending on the crosslinker used.

WHERE 2004/033171 describes the use of with alkanols or polyols modified bis (hydroxymethyl) -4,5-dihydroxyimidazolidinone, 1,3-bis (hydroxymethyl) urea, 1,3-bis (methoxymethyl) urea, 1-hydroxymethyl-3-methylurea, 1,3-bis (hydroxymethyl) imidazolidin-2-one, 1,3-dimethyl-4,5-dihydroxyimidazolidin-2-one or tetra (hydroxymethyl) acetylenediurea as impregnating agent for wood. The impregnating agents to lead for improving the durability, dimensional stability and surface hardness of Wooden bodies Solid wood.

The problem with the wood bodies obtained using crosslinkable urea or melamine compounds is their brittleness and the reduction of the breaking impact strength. It also increases with veneers, the danger of breakage or cracking during further processing. In addition, the modification with alcohols and in particular with Oligoethylenglykolen leads to increased hydrophilicity and water absorption and thus to a higher susceptibility to harmful organisms.

Of the The present invention is therefore based on the object curable compositions for impregnation of lignocellulosic materials, in particular wood, which at least partially solve the problems presented here.

These and further tasks are described with the following aqueous, curable Compositions solved.

• a) wenigstens eine niedermolekulare Verbindung V, welche wenigstens zwei N-gebundene Gruppen der Formel CH₂OH und/oder eine zwei Stickstoffatome verbrückende 1,2-Bishydroxyethan-1,2-diyl-Gruppe aufweist, und
• b) wenigstens ein Oligo- oder Polyalkylenetherpolyol P mit im Mittel wenigstens 2 OH-Gruppen, insbesondere 2 bis 6 OH-Gruppen, je Molekül, der wenigstens eine zwei- oder mehrwertige aliphatische oder cycloaliphatische Gruppe mit wenigstens 3 C-Atomen, insbesondere mit 3 bis 10 C-Atomen aufweist, und/oder
• c) ein Reaktionsprodukt einer niedermolekularen Verbindung V mit dem Polyalkylenetherpolyol.

Accordingly, the invention relates to aqueous, curable compositions comprising:

• a) at least one low molecular weight compound V, which has at least two N-bonded groups of the formula CH ₂ OH and / or a two nitrogen atoms bridging 1,2-bishydroxyethane-1,2-diyl group, and
• b) at least one oligo- or polyalkylene ether polyol P having on average at least 2 OH groups, in particular 2 to 6 OH groups, per molecule containing at least one divalent or polyvalent aliphatic or cycloaliphatic group having at least 3 C atoms, in particular 3 has up to 10 carbon atoms, and / or
• c) a reaction product of a low molecular weight compound V with the polyalkylene ether polyol.

The impregnated using the compositions of the invention Lignocellulosematerialien show after hardening an increased surface hardness and an improved shrinkage behavior and thus an improved dimensional stability on. In addition, they are characterized by a comparison with the state of Technology higher elasticity and thus by an improved breaking strength, the especially with wooden bodies made of solid or glued wood and veneer materials for carrying comes. Veneers themselves are lighter due to the improved elasticity to process. Furthermore, the hydrophilicity of the invention impregnated Lignocellulosematerials reduced compared to the prior art, thus reducing the absorption of water and so the durability is improved.

The inventive compositions comprise as component a) at least one low molecular weight compound V. By definition, the compound has at least 2, for example 2, 3, 4, 5 or 6 CH ₂ -OH groups and especially 2 CH ₂ -OH groups which a nitrogen atom are bonded. When the compound V has two or more nitrogen atoms, it may have, instead or in combination therewith, at least one 1,2-bishydroxyethane-1,2-diyl group. Typically, compound V is low molecular weight and has a number average molecular weight below 500 daltons and more preferably below 300 daltons.

• – 1,3-Bis(hydroxymethyl)-4,5-dihydroxyimidazolidin-2-on,
• – 1,3-Bis(hydroxymethyl)harnstoff,
• – 1,3-Bis(hydroxymethyl)imidazolidin-2-on (Dimethylolethylenharnstoff),
• – 1,3-Bis(hydroxymethyl)-1,3-hexahydropyrimidin-2-on (Dimethylolpropylenharnstoff)
• – 1,3-Bis(methoxymethyl)-4,5-dihydroxyimidazolidin-2-on (DMeDHEU),
• – Tetra(hydroxymethyl)acetylendiharnstoff und
• – niedermolekulare Melamin-Formaldehyd Harze, insbesondere wenigstens 2-fach, z.B. 2-, 3-, 4-, 5- oder 6-fach methyloliertes Melamin und speziell Trimethylolmelamin (2,4,6-Tris[bis(hydroxymethyl)amino]triazin).

Examples of compounds V are:

• 1,3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidin-2-one,
• 1,3-bis (hydroxymethyl) urea,
• 1,3-bis (hydroxymethyl) imidazolidin-2-one (dimethylolethyleneurea),
• 1,3-bis (hydroxymethyl) -1,3-hexahydropyrimidin-2-one (dimethylolpropyleneurea)
• 1,3-bis (methoxymethyl) -4,5-dihydroxyimidazolidin-2-one (DMeDHEU),
• Tetra (hydroxymethyl) acetylenediurea and
• - Low molecular weight melamine-formaldehyde resins, in particular at least 2 times, for example 2-, 3-, 4-, 5- or 6-fold methylolated melamine and especially trimethylolmelamine (2,4,6-tris [bis (hydroxymethyl) amino] triazine ).

Preference is given to urea compounds which each carry a CH ₂ -OH group on both nitrogen atoms of the urea unit. In particular, compound V is 1,3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidin-2-one.

Compounds V of the type in question are described, for example, from the WO 2004/033170 and WO 2004/033171 cited above and from K. Fisher et al. "Textile Auxiliaries - Finishing Agents" Chap. 7.2.2 in Ullmann's Encyclopedia of Industrial Chemistry, 5th Ed. on CD-ROM, Wiley-VCH, Weinheim 1997 and literature cited there, eg US 2,731,364 . US 2,930,715 are known and are usually used in the form of their aqueous compositions as crosslinkers for textile finishing. Incidentally, crosslinkable compounds V are commercially available.

Farther contains the aqueous composition according to the invention at least one oligo- or polyalkylene ether polyol P. This is it is an aliphatic oligo- or polyether, which in addition to aliphatic Ethereinheiten at least 2 OH groups in the molecule and additionally at least one aliphatic or cycloaliphatic Structural unit with 3 or more carbon atoms, e.g. 3 to 10 and in particular Has 3 to 6 carbon atoms. These structural units can be repeat units or in the preparation of the oligo- or polyether used starters result.

The in the compositions of the invention contained oligo- or Polyalkylenetherpolyole P often have number average molecular weight in the range of 120 to 10,000 daltons, preferably in the range of 180 to 8000 daltons, in particular in the range of 250 to 6000 daltons and especially in the range of 300 up to 4000 daltons.

• α) Oligoetherdiole der Formel HO-[Alk-O]_qH, worin Alk für C₃-C₁₀-Alkylen und insbesondere für C₃-C₄-Alkylen steht, z.B. für 1,2-Propandiyl, 1,3-Propandiyl, 1,3- oder 1,4-Butandiyl und q für eine Zahl im Bereich von 2 bis 100, insbesondere 2 bis 50 und speziell 3 bis 30 steht,
• β) Copolymere und Cooligomere von Ethylenoxid mit C₃-C₁₀-Alkylenoxiden, insbesondere mit C₃-C₄-Alkylenoxiden und speziell mit Propylenoxid. In den Cooligomeren und Copolymeren können die von Ethylenoxid abgeleiteten Struktureinheiten statistisch oder blockweise angeordnet sein, wobei letzteres der Regelfall ist. Hierunter sind insbesondere Triblockcopolymere mit einem zentralen Polypropylenoxid-Block und terminalen Polyethylenoxid-Blöcken sowie Triblockcopolymere mit einem zentralen Polyetheroxid-Block und terminalen Polypropylenoxid-Blöcken bevorzugt;
• γ) Oligomere und Polymere, die durch Polymerisation von C₂-C₁₀-Alkylenoxiden, insbesondere von C₂-C₄-Alkylenoxiden und speziell von Ethylenoxid und/oder Propylenoxid in Gegenwart eines aliphatischen oder cycloaliphatischen Polyols mit wenigstens 2 OH-Gruppen, z.B. 2 bis 6 OH-Gruppen, und wenigstens 3 C-Atomen, insbesondere 3 bis 10 C-Atomen als Starter erhältlich sind. Typische Starter umfassen aliphatische Diole, Triole und Tetrole mit 3 bis 10 C-Atomen wie 1,3-Propandiol, 1,3- und 1,4-Butandiol, 1,5-Pentandiol, 1,6-Hexandiol, Glycerin, Trimethylolethan, Trimethylolpropan, Erythrit, und Pentaerythrit, sowie Pentite und Hexite wie Ribit, Arabit, Xylit, Dulcit, Mannit und Sorbit sowie Inosit, und dergleichen.
• δ) Oligomere und Polymere, die durch Polymerisation von C₂-C₁₀-Alkylenoxiden, insbesondere von C₂-C₄-Alkylenoxiden und speziell von Ethylenoxid und/oder Propylenoxid in Gegenwart eines Amins, das wenigstens 3 C-Atome, z.B. 3 bis 20 C-Atome, und wenigstens eine, insbesondere wenigstens 2 und speziell 2, 3 oder 4 NH₂-Gruppen aufweist, als Starter erhältlich ist. Typische Amin-Starter umfassen aliphatische und cycloaliphatische Diamine, Triamine und Tetramine mit wenigstens 3, z.B. mit 3 bis 20 C-Atomen insbesondere Alkylendiamine, die gegebenenfalls in der Alkylenkette eine oder mehrere, z.B. 1, 2 oder 3 nicht benachbarte Heteroatomgruppen, ausgewählt unter NH, N-(C₁-C₄-alkyl) und O, aufweisen können mit 3 bis 20 C-Atomen wie Diethylentriamin, Triethylentetramin, Tetraethylenpentamin, Propylendiamin-1,3, Dipropylentriamin, 3-Amino-1-(2-aminoethyl)aminopropan, 1,5,8,12-Tetraazadodecan, Hexamethylendiamin, Dihexamethylentriamin, 1,6-Bis-(3-aminopropylamino)hexan und N-Methyldipropylentriamin und Polyethylenimin (Lupasol^®-Marken der BASF).
• ε) Oligomere sowie Polymere, welche durch Polymerisation von C₂-C₁₀-Alkylenoxiden, insbesondere von Ethylenoxid und/oder Propylenoxid in Gegenwart eines Oligoetherdiols der Formel HO-[(CH₂)_m-O]_nH, worin m für 3, 4, 5 oder 6 und speziell für 4 steht und n für eine Zahl im Bereich von 2 bis 30 steht, als Starter erhältlich sind.
• (ζ) Oligomere und Polymere, welche durch Polymerisation von C₃-C₁₀-Alkylenoxiden, insbesondere von Propylenoxid in Gegenwart eines Oligo- oder Polyethylenoxids erhältlich sind.

Examples of oligo- or polyalkylene ether polyols are:

• α) oligoether diols of the formula HO- [Alk-O] _q H, where Alk is C ₃ -C ₁₀ -alkylene and in particular C ₃ -C ₄ -alkylene, for example, 1,2-propanediyl, 1,3-propanediyl, 1,3- or 1,4-butanediyl and q is a Number in the range of 2 to 100, in particular 2 to 50 and especially 3 to 30,
• β) Copolymers and cooligomers of ethylene oxide with C ₃ -C ₁₀ -alkylene oxides, in particular with C ₃ -C ₄ -alkylene oxides and especially with propylene oxide. In the co-oligomers and copolymers, the structural units derived from ethylene oxide can be arranged randomly or in blocks, the latter being the rule. Of these, particularly preferred are triblock copolymers having a central polypropylene oxide block and terminal polyethylene oxide blocks, and triblock copolymers having a central polyether oxide block and terminal polypropylene oxide blocks;
• γ) oligomers and polymers obtained by polymerization of C ₂ -C ₁₀ -alkylene oxides, in particular of C ₂ -C ₄ -alkylene oxides and especially of ethylene oxide and / or propylene oxide in the presence of an aliphatic or cycloaliphatic polyol having at least 2 OH groups, for example 2 to 6 OH groups, and at least 3 C-atoms, in particular 3 to 10 C-atoms are available as starters. Typical initiators include aliphatic diols, triols and tetrols having from 3 to 10 carbon atoms, such as 1,3-propanediol, 1,3- and 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, glycerol, trimethylolethane, Trimethylolpropane, erythritol, and pentaerythritol, as well as pentites and hexites such as ribitol, arabitol, xylitol, dulcitol, mannitol and sorbitol, and inositol, and the like.
• δ) oligomers and polymers obtained by polymerization of C ₂ -C ₁₀ alkylene oxides, in particular of C ₂ -C ₄ alkylene oxides and especially of ethylene oxide and / or propylene oxide in the presence of an amine which has at least 3 C atoms, for example 3 to 20 C atoms, and at least one, especially at least 2 and especially 2, 3 or 4 NH ₂ groups, is available as a starter. Typical amine initiators include aliphatic and cycloaliphatic diamines, triamines and tetramines having at least 3, eg having 3 to 20 carbon atoms, in particular alkylenediamines which optionally have one or more, eg 1, 2 or 3, non-adjacent heteroatom groups in the alkylene chain, selected from NH , N- (C ₁ -C ₄ alkyl) and O, may have from 3 to 20 carbon atoms, such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, propylenediamine-1,3, dipropylenetriamine, 3-amino-1- (2-aminoethyl) aminopropane, 1,5,8,12-tetraazadodecane, hexamethylenediamine, dihexamethylenetriamine, 1,6-bis- (3-aminopropylamino) hexane and N-methyldipropylenetriamine and polyethyleneimine (Lupasol ^® brands from BASF).
• ε) oligomers and polymers which by polymerization of C ₂ -C ₁₀ alkylene oxides, in particular of ethylene oxide and / or propylene oxide in the presence of a Oligoetherdiols the formula HO - [(CH ₂ ) _m -O] _n H, where m is 3, 4, 5 or 6 and especially 4 and n is a number in the range of 2 to 30, available as starters.
• (ζ) Oligomers and polymers which are obtainable by polymerization of C ₃ -C ₁₀ alkylene oxides, in particular of propylene oxide in the presence of an oligo- or polyethylene oxide.

Preference is given to polyalkylene ether polyols P of the groups α), β), ε) and (ζ), in particular those having an OH functionality in the range from 2 to 6 and especially in the range from 2 to 4. Among the cooligomers and copolymers β) are in particular those with an ethylene oxide content of not more than 80 wt .-%, for example 5 to 80 wt .-% and especially 5 to 60 wt .-%, based on the total weight of the co-oligomers / copolymers preferred. Among the oligomers and polymers ε) and (ζ) are in particular those having an ethylene oxide content of not more than 80 wt .-%, for example 5 to 80 wt .-% and especially 5 to 60 wt .-%, based on the Ge total weight of the oligomers / polymers, preferably.

Oligomers of the groups α), β), γ), δ), ε) and (ζ) are known to the person skilled in the art, for example from FE Bailey et. al. "Polyoxyalkylene" in Ullmann's Encyclopedia of Industrial Chemistry, 5th Ed. on CD-ROM, Wiley-VCH, Weinheim, 1997, and references cited therein, and are commercially available, for example under the trade names Pluriol® ^® - Pluronic ^® - Degressal ^® - polyTHF ^® - Tetronic ^® BASF, Synperonic ^® brands Brands of Unigema and Sepabase ^® brands of Baker petrolites

The molar ratio from compound V to the polyalkylene ether polyol P is usually in the range of 1: 0.005 to 1: 2, preferably in the range of 1: 0.01 to 1: 1, and more preferably in the range of 1: 0.02 to 1 : 0.5. The weight ratio the compound V to the polyalkylene ether polyol is preferably in the range of 1: 0.05 to 1: 5, in particular in the range of 1 : 0.1 to 1: 1.

The Total concentration of compounds V + P in the aqueous Composition is usually in the range 5 to 60 wt .-%, often in the range of 10 to 60% by weight and in particular in the range of 15 to 50 wt .-%, based on the Total weight of the composition.

The aqueous compositions according to the invention may also contain one or more alcohols A, for example C ₁ -C ₆ -alkanols, C ₂ -C ₆ -polyols, or mixtures of these alcohols. Examples of suitable C _1-6 -alkanols are methanol, ethanol, n-propanol, isopropanol, n-butanol and n-pentanol, preference being given to methanol. Suitable polyols are ethylene glycol, diethylene glycol, triethylene glycol, 1,2- and 1,3-propylene glycol, 1,2-, 1,3-, and 1,4-butylene glycol, glycerol. However, the proportion of such alcohols will usually not exceed 20% by weight, based on the total weight of the composition. The molar ratio of polyols to the polyalkylene ether polyols P will typically be below 1: 1. In particular, the composition contains less than 5% by weight of C ₂ -C ₆ polyols, based on the total weight of C ₂ -C ₆ polyol + polyalkylene ether polyol P. The total amount of compound V, polyether polyol P and alcohol A usually makes 10 to 60 wt .-% and in particular 20 to 50 wt .-% of the total weight of the aqueous composition.

The for impregnation used aqueous composition according to the invention contains usually at least one catalyst K, which crosslinking the compound V, the polyether polyol and optionally present Alcohol A causes. In general, as catalysts K metal salts from the group of metal halides, metal sulphates, metal nitrates, Metal phosphates, metal tetrafluoroborates; boron trifluoride; ammonium salts from the group of ammonium halides, ammonium sulfate, ammonium oxalate and diammonium phosphate; as well as organic carboxylic acids, organic sulfonic acids, boric acid, Phosphoric acid, sulfuric acid and hydrochloric acid suitable.

Examples for as Catalysts K suitable metal salts are in particular magnesium chloride, Magnesium sulfate, zinc chloride, lithium chloride, lithium bromide, aluminum chloride, Aluminum sulfate, zinc nitrate and sodium tetrafluoroborate.

Examples for as Catalysts K suitable ammonium salts are in particular ammonium chloride, ammonium sulfate, Ammonium oxalate and diammonium phosphate.

When Catalysts K are especially water-soluble organic carboxylic acids such maleic acid, formic acid, Citric acid, tartaric acid and oxic acid, benzenesulfonic acids, such as p-toluenesulfonic acid, but also inorganic acids, like hydrochloric acid, Sulfuric acid, boric acid and their mixtures are suitable.

Preferably the catalyst K is magnesium chloride, zinc chloride, magnesium sulfate, Aluminum sulfate and mixtures thereof, with magnesium chloride is particularly preferred.

The Catalyst K is usually used the aqueous Add composition just before impregnation. He usually becomes in an amount of 1 to 20 wt .-%, in particular 2 to 10 wt .-%, based on the total weight of those contained in the aqueous composition curable Components used. The concentration of the catalyst, based on the total weight of the aqueous Composition is usually in the range of 0.1 to 10 wt .-% and in particular in the range of 0.5 to 5 wt .-%.

The aqueous compositions according to the invention can furthermore also contain effect substances, For example, colorants such as soluble dyes and / or pigments, active against wood-damaging and / or wood-destroying microorganisms, such as biocidal, fungicidal or insecticidal agents, UV stabilizers and / or antioxidants. These can be present in the compositions according to the invention in dissolved or dispersed form. In this way, impregnated materials containing such effect substances are obtained. By curing the composition also takes place a fixation of Materialein, so that a Leaching, as it is observed in conventional impregnation with effect substances, no longer takes place. The compositions of the invention may also contain dispersed waxes as well as the surfactants required to disperse these waxes.

The Compositions of the invention are suitable for impregnation any lignocellulosic material of any size. In particular, they are suitable for impregnating wood, including solid wood, Wood-based materials and wood materials for the production of wood-based materials. The compositions of the invention are suitable both for impregnation finely divided materials such as fibers, chips, strands, chips, chips and the like, for impregnation flat thinner Materials with thicknesses ≤ 5 mm, in particular ≤ 1 mm, such as veneers and in particular also for impregnating large-sized parts with minimum dimensions above 1 mm, in particular ≥ 5 mm, especially ≥ 10 mm.

The Compositions of the invention are particularly suitable for impregnating wood or wood-based materials or wood materials for the production of wood-based materials, especially for impregnating Solid or solid wood. Suitable are basically all types of wood, in particular those containing at least 30%, in particular at least 50% of their dry weight can absorb water and particularly preferably those which satisfy the classes of impregnability (or impregnability) 1 or 2 according to DIN EN 350-2 can be assigned. These include, for example, wood from conifers like pine, spruce, Douglas fir, larch, Pine, fir, coastal fir, Cedar, stone pine, as well as woods of deciduous trees, e.g. Maple, hardmaple, acacia, ayons, birch, pear, beech, oak, Alder, aspen, ash, wild berry, hazel, hornbeam, cherry, chestnut, Linden, American walnut, Poplar, Olive, Robinia, Elm, Walnut, Rubber tree, zebrano, willow, Turkey oak and the like. Are suitable also woods, which already with a hardenable Impregnated compound are and cured were. The advantages of the invention come especially with the following woods to bear: beech, spruce, Pine, poplar, ash and maple.

The Compositions of the invention are also suitable for impregnation other lignocellulosic materials other than wood, e.g. of natural fiber materials such as bamboo, bagasse, cotton stalks, jute, Sisal, straw, flax, coconut fiber, banana fiber, reed, e.g. Miscanthus, Ramie, hemp, manila hemp, esparto (alfagras), rice husks and cork.

Accordingly The present invention relates to the use of those described herein Compositions for impregnation of lignocellulosic materials, in particular wood, wood-based materials and finely divided materials for the production of wood-based materials.

The The invention also relates to a method for treating, in particular for impregnation of lignocellulosic materials, including impregnating of the lignocellulosic material with an aqueous according to the invention Composition and a crosslinking step at elevated temperature.

The available according to the invention Lignocellulosic materials, in particular bodies of solid wood and wood-based materials, especially veneer materials are characterized by a better breaking strength and less brittleness than the products of the prior art. In addition, a hydrophobic effect is achieved.

The Impregnate can be more usual in itself Manner, e.g. by dipping, by applying vacuum if necessary in combination with printing or by conventional application methods like painting, spraying and the same. The particular impregnation method used naturally depends on the dimensions of the to be impregnated Materials off. Lignocellulosic materials with small dimensions like Chips or Beaches as well as thin Veneers, i. Materials with a large surface to volume ratio, can be with little effort, e.g. impregnate by dipping or spraying, whereas lignocellulosic materials of larger dimensions, in particular Materials whose smallest dimension is more than 5 mm, e.g. Solid wood, molded parts made of solid wood or wood-based materials, using Pressure or vacuum, in particular by combined use of Pressure and vacuum impregnated become. Advantageously, the impregnation at a temperature below 50 ° C, e.g. in the range of 15 to 50 ° C carried out.

The Conditions of impregnation are usually chosen like this be that the absorbed amount of curable components of the aqueous Composition at least 1 wt .-%, based on the dry matter of the untreated material. The recorded amount of curable Ingredients may be up to 100 wt .-%, based on the dry mass of untreated materials are and often in the range of 1 to 60 Wt .-%, preferably in the range of 5 to 50 wt .-%, and in particular in Range of 10 to 40 wt .-%, based on the dry weight of the used untreated material, lies. The humidity of the water used for watering, untreated materials is not critical and can be, for example to 100%. Here and below, the term "moisture" is synonymous with the Term residual moisture content according to DIN 52183. In particular, the Residual moisture content below the fiber saturation point of the lignocellulosic material. Often it is in the range of 1 to 80% and especially 5 to 50%.

To the Dipping is the lignocellulosic material, optionally after one Pre-drying, in a container, which the watery Contains composition dipped. The dipping is preferably done over a period of a few Seconds to 24 h, especially 1 min to 6 h. The temperatures are usually in the range of 15 ° C up to 50 ° C. Here, the lignocellulosic material absorbs the aqueous composition, wherein the concentration of the non-aqueous constituents (i.e. curable Constituents) in the aqueous Composition, by the temperature and the duration of treatment the amount of these components taken up by the lignocellulosic material can be controlled. Actually absorbed amount of components, the expert in a simple Way over the weight gain of the impregnated Materials and the concentration of the components in the aqueous Identify and control composition. Veneers, for example using press rolls, called calenders, which are in the aqueous impregnating be pre-pressed. This while relaxing in lignocellulosic material occurring vacuum leads then to accelerated uptake of aqueous impregnating composition.

The Impregnate takes place advantageously by combined use of reduced and elevated Print. For this purpose, the lignocellulosic material, which is usually has a humidity in the range of 1% to 100%, initially below reduced pressure, often in the range of 10 to 500 mbar and especially in the range of 40 to 100 mbar, with the aqueous Composition brought into contact, e.g. by dipping in the aqueous Composition. The time period is usually in the range of 1 min to 1 h. This concludes a phase at elevated Pressure, e.g. in the range of 2 to 20 bar, especially in 4 to 15 bar and especially 5 to 12 bar, on. The duration of this phase is usually in the range of 1 min to 12 h. The temperatures are usually in the range of 15 to 50 ° C. Here, the lignocellulosic material absorbs the aqueous composition, wherein the concentration of the non-aqueous constituents (i.e. curable Constituents) in the aqueous Composition, pressure, temperature and duration of treatment the amount of these absorbed by the lignocellulosic material Components can be controlled. The actually recorded amount can over here too the weight gain of the lignocellulosic material is calculated.

Farther can the impregnation by conventional methods of applying liquids surfaces take place, e.g. by spraying or rolling or brushing. For this one sets advantageously a material having a humidity of not more than 50%, in particular not more than 30%, e.g. in the range of 12% to 30%. The application usually takes place at temperatures in the range of 15 to 50 ° C. The spraying can be done in the usual way Way in all for the spraying of flat or finely divided bodies suitable Devices are made, e.g. by means of nozzle arrangements and the like. When brushing or rolling the desired amount of aqueous Composition with rollers or brushes on the sheet material applied.

Then done the hardening the crosslinkable components of the aqueous composition. The hardening may be analogous to the methods described in the prior art carried out become. e.g. according to those described in WO 2004/033170 and WO 2004/033171 Method.

The hardening Typically, this is done by treating the impregnated material at temperatures above 80 ° C, in particular above 90 ° C, e.g. in the range of 90 to 220 ° C and especially in the range of 100 to 200 ° C. The time required for curing is typically in the range of 10 minutes to 72 hours. For veneers and finely divided lignocellulosic materials may tend to have higher temperatures and shorter times be applied. When curing not only the pores in the lignocellulosic material with the hardened impregnating agent become stuffed, but it creates a cross-linking between impregnating agent and the lignocellulosic material itself.

possibly you can before hardening a drying step, in the following also predrying step carry out. Here are the volatile Ingredients of the aqueous Composition, in particular the water and excess organic solvents, those in the curing / networking do not react, partially or completely removed. pre-drying means that the lignocellulosic material is below the fiber saturation point is dried, depending on the type of material at about 30 wt .-% lies. This predrying works especially with large format wood bodies the risk of cracking. For small-sized lignocellulosic materials, for example, veneers, chips, Chips, strands, fibers, etc., the pre-drying can be omitted. at wood bodies with larger dimensions However, the predrying is beneficial. Unless a separate pre-drying carried out is, this takes place advantageously at temperatures in the range from 20 to 80 ° C. Dependent on from the chosen one Drying temperature may be a partial or complete cure / crosslinking the curable components contained in the composition take place. The combined predrying / hardening the impregnated Materials are usually made by applying a temperature profile ranging from 50 ° C to 220 ° C, in particular from 80 to 200 ° C can reach.

The Curing / drying can be used in a conventional fresh air exhaust system, e.g. one Drum dryer performed become. Pre-drying preferably takes place in such a way that the moisture content of the finely divided lignocellulosic materials the pre-drying not more than 30%, in particular not more than 20%, based on the dry matter. It can be an advantage the drying / hardening up to a moisture content <10% and in particular <5%, based on the dry matter, lead. The moisture content can by the temperature, duration and pressure selected during pre-drying be controlled in a simple manner.

Possibly will be before drying / curing adhering liquid remove by mechanical means.

at large format Materials, it has proven these during drying / hardening to fix, e.g. in heating presses.

The impregnated according to the invention Wood materials can, if it is not already made-up end products, be further processed in a conventional manner, in the case of finely divided Materials e.g. to moldings like OSB (oriented structural board) boards, chipboard, wafer boards, OSL panels and OSL moldings (Oriented Strand Lumber), PSL panels and PSL moldings (Parallel Strand Lumber). Insulating boards and medium density (MDF) and high-density (HDF) fiberboard, wood-plastic composites (WPC) and the like, in the case of veneers to veneer materials such as veneered fibreboard, veneered blockboard, veneered chipboard including veneered OSL and PSL sheets (oriented or parallel strand lumber), plywood, Laminated wood, plywood, laminated veneer lumber (for example Kerto plywood), Multiplex boards, laminated veneer materials (Laminated Veneer Lumber LVL), decorative Veneer materials such as cladding, ceiling and prefinished parquet panels but also non-surface, 3-dimensionally shaped components such as plywood moldings, plywood moldings and any other, coated with at least one veneer layer Moldings. Further processing can be done immediately afterwards to the impregnation, while or following the hardening of the taken from the lignocellulosic material constituents V, P and optionally A done. In the case of impregnated Veneering is advantageously before the further processing the curing step or together with the curing step carry out. For moldings From finely divided materials becomes the shaping step and hardening step preferably carried out simultaneously.

Provided it is in the impregnated Lignocellulosematerial around solid wood or a prefabricated wood material this can be in usual Manner processed who, for. by sawing, planing, grinding etc. Impregnated according to the invention and hardened Solid wood is particularly suitable for the production of objects that Moisture and especially weathering, e.g. for timber, Beams, components of wood, for Wooden balconies and wooden terraces, shingles, fences, wooden poles, railway sleepers, in shipbuilding for the interior and deck structures.

According to the following general recipe, the compositions (impregnating agents) of Examples 1 to 4 according to the invention were prepared by mixing the constituents. DMDHEU was used as an aqueous formulation. The% data are to be understood as wt .-% of the respective component, based on the total weight of the composition: recipe: DMDHEU 22.5% MgCl ₂ × 6H ₂ O 1.5% additive 5.0% water 63.5%

example 1: The additive was a polyethylene oxide-polypropylene oxide triblock copolymer used with central polypropylene oxide block. The central polypropylene block had a number average molecular weight of about 850 daltons. The ethylene oxide content was 10% by weight, based on the polymer.

example 2: The additive was a polyethylene oxide-polypropylene oxide triblock copolymer used with central polypropylene oxide block. The central polypropylene block had a number average molecular weight of about 1100 daltons. The ethylene oxide content was 30% by weight, based on the polymer.

example 3: The additive was a polyethylene oxide-polypropylene oxide triblock copolymer used with central polypropylene oxide block. The central polypropylene block had a number average molecular weight of about 1750 daltons. The ethylene oxide content was 10% by weight, based on the polymer.

example 4: The additive was a polyethylene oxide-polypropylene oxide triblock copolymer used with central polyethylene oxide block. The block copolymer had a number average molecular weight of about 2150 daltons. The ethylene oxide content was 20% by weight, based on the polymer.

Comparative Example: The additive was replaced by the same amount of water.

applications

In In the following experiments, beech wood samples measuring 10 × 10 × 150 mm were used used.

The Wood samples were placed in an impregnation plant brought in. The drinking system was exposed for 30 minutes to a vacuum of absolutely 40 mbar. Subsequently was the drinking plant with the impregnating agent absolutely flooded while maintaining a vacuum of 50 mbar. Subsequently was a pressure of 12 bar for 2 hours. The printing phase was ended and the residual liquid has been removed.

The Wood samples were then in an over temperature and humidity Controllable drying chamber stored and fixed so that a recycling impossible was. The chamber was maintained while maintaining a relative humidity from 95% to 120 ° C brought. These conditions have been retained for as long as the Interior of the wood samples over a period of 48 hours a temperature of at least 120 ° C prevailed.

Of the samples obtained, the maximum break-up work value was then determined analogously to DIN 52189. The results are shown in the following table:

Claims (16)

Aqueous, curable composition comprising a) at least one low molecular weight compound V which has at least two N-bonded groups of the formula CH ₂ OH and / or a 1,2-bishydroxyethane-1,2-diyl group bridging two nitrogen atoms, and b ) at least one oligo- or polyalkylene ether polyol P having on average at least 2 OH groups, per molecule, the at least one two- or more-valent aliphatic or cycloaliphatic group having at least 3 C-Ato men, and / or c) a reaction product of a low molecular weight compound V with the polyalkylene ether polyol. Composition according to claim 1, wherein the oligo- or polyalkylene ether polyol P has a number average molecular weight ranging from 120 to 10,000 daltons. A composition according to claim 1 or 2, wherein the oligo- or polyalkylene ether polyol is selected from - oligoether diols of the formula HO- [Alk-O] _q H, where Alk is C ₃ -C ₄ -alkylene, for example 1,3-propanediyl, 1,3- or 1,4-butanediyl and q is a number in the range from 2 to 30, - copolymers and cooligomers of ethylene oxide with C ₃ -C ₁₀ -alkylene oxides, oligomers and polymers which are obtainable by polymerization of C ₂ -C ₁₀ -alkylene oxides in the presence of an aliphatic or cycloaliphatic polyol having at least 2 OH groups and at least 3 C atoms as initiators, and Oligomers and polymers which are obtainable by polymerization of C ₂ -C ₁₀ alkylene oxides in the presence of an amine having at least one NH ₂ group and at least 3 C atoms as starters, - oligomers and polymers which by polymerization of C ₂ -C ₁₀ -alkylene oxides in the presence of a Oligoetherdiols the formula HO - [(CH ₂ ) _m -O] _n H, wherein m is 3, 4, 5 or 6 and n is a number in the range of 2 to 30, are available as starters, and - oligomers and polymers obtained by polymerization of C ₃ -C ₁₀ alkylene oxides in the presence of a polyethylene oxide are available. A composition according to any one of the preceding claims, wherein the connection V is selected is under 1,3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidin-2-one, 1,3-bis (hydroxymethyl) urea, 1,3-bis (hydroxymethyl) imidazolidin-2-one (Dimethylol) - 1,3-bis (hydroxymethyl) -1,3-hexahydropyrimidin-2-one (Dimethylolpropyleneurea) 1,3-bis (methoxymethyl) -4,5-dihydroxyimidazolidin-2-one (DMeDHEU) - tetra (hydroxymethyl) acetylenediurea and - low molecular weight Melamine-formaldehyde resins. A composition according to any one of the preceding claims containing the compound V and the polyalkylene ether polyol P in a total amount from 5 to 60 wt .-%, based on the total weight of the aqueous Composition. A composition according to any one of the preceding claims containing the compound V and the polyalkylene ether polyol P in a molar ratio of 1: 0.005 to 1: 2. A composition according to any one of the preceding claims, wherein the watery Composition in addition contains a catalyst K, which is a crosslinking reaction of the compound V with the polyalkylene ether polyol P causes. A composition according to claim 7, wherein the catalyst K selected is among metal salts from the group of metal halides, metal sulfates, Metal nitrates, metal phosphates, metal tetrafluoroborates; boron trifluoride; Ammonium salts from the group of ammonium halides, ammonium sulfate, Ammonium oxalate and diammonium phosphate; organic carboxylic acids, organic sulfonic acids, boric acid, Phosphoric acid, sulfuric acid and Hydrochloric acid. Use of a composition according to any one of the preceding claims for impregnating Lignocellulosic materials. Use according to claim 9, wherein the lignocellulosic material Wood or a wood material is. Process for treating lignocellulosic materials, comprising impregnating of the lignocellulosic material having a composition according to egg nem of the preceding claims and a crosslinking step at elevated temperature. The method of claim 11, wherein the lignocellulosic material Wood is. The method of claim 12, wherein the lignocellulosic material a solid wood body is. The method of claim 12, wherein the lignocellulosic material a wood veneer is. The method of claim 12, wherein the lignocellulosic material a finely divided material is and the method additionally the Further processing comprises a molded body. Lignocellulosic material, obtainable by a process according to one of the claims 11 to 15.