EP1934026A1

EP1934026A1 - Use of modified wood materials for producing articles

Info

Publication number: EP1934026A1
Application number: EP06793743A
Authority: EP
Inventors: Arend Jouke Kingma; Franz Weingart; Stefan Schaffert; Oliver JÜTTNER; Holger Militz; Andreas Krause; Falko Wepner
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 2005-09-23
Filing date: 2006-09-22
Publication date: 2008-06-25
Also published as: CA2622011A1; RU2008115237A; CN101267921A; AU2006293913A1; NO20081102L; WO2007033988A1; US20080226932A1; KR20080055922A; DE102005045533A1; BRPI0616279A2

Abstract

The present invention relates to the use of modified wood materials for producing articles which comprise at least one wood material.

Description

Use of modified woodwork materials for the manufacture of articles

description

The present invention relates to the use of modified wood materials for making articles comprising at least one wood material.

The natural durability of wood is influenced by the behavior of wood during changes in humidity. The swelling and shrinkage associated with the ability of the wood to absorb and dispense water creates problems in the manufacture of articles made wholly or partly from wood materials, especially when two or more parts are frictionally or positively connected are, since the strength of such connections between wood parts is naturally reduced by the swelling / shrinkage behavior of the wood in particular. In extreme cases, the swelling / shrinkage behavior destroys the non-positive connection.

In addition, the dimensional change often leads to destruction of the wood surface of the material and coatings applied thereto, so that the wood is exposed to biological decomposition processes to a greater extent.

To improve durability, wood and comparable lignocellulose-based materials are often rendered hydrophobic, e.g. B. by treatment with wax-containing impregnants. This makes penetration of water into the pores of the material more difficult.

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

It is known from the publication "Treatment of timber with water soluble dimethylol resins to improve the dimensional stability and durability", published in Wood Science and Technology 1993, pages 347-355, to improve the shrinkage and swelling properties of wood as well as the resistance against fungi and insects to treat this with an impregnating agent, which consists of an aqueous solution of dimethyloldihydroxyethylenurea (DMDHEU or 1, 3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidinon-2) and a catalyst. At elevated temperature There is a reaction of the DMDHEU with itself and the wood. In this way, wooden bodies with dimensions of 20 mm x 20 mm x 10 mm were examined. The method described can only be used with small dimensions of the wood body, because they tend to crack at larger dimensions.

WO 2004/033170 describes a process for improving the surface hardness of wood, in which an untreated wood body with an aqueous solution of a crosslinkable nitrogen compound from the group 1, 3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidinon-2, with a Ci _-5- alcohol, a polyol or their Gem see modified 1, 3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidinon-2, 1, 3-dimethyl-4,5-dihydroxyimidazolidinon-2, dimethylolurea, bis (methoxy - Methyl) urea, Tetramethylolacetylenediharnstoff, 1, 3-bis (hydroxymethyl) - imidazolidinone-2 and Methylolmethylharnstoff containing a crosslinking of these compounds catalyst, impregnated and then cured while maintaining moist conditions at elevated temperature. WO 2004/033171 discloses a similar process in which the impregnating solution comprises a bis (hydroxymethyl) -4,5-dihydroxyimidazolidinone, 1,3-bis (hydroxymethyl) urea, 1,3-bis, modified with alkanols or polyols (methoxymethyl) urea, 1-hydroxymethyl-3-methylurea, 1, 3-bis (hydroxymethyl) imidazolidin-2-one, 1, 3-dimethyl-4,5-dihydroxyimidazolidin-2-one or tetra (hydroxymethyl) acetlyendiurea.

PCT / EP2006 / 004020 (older German patent application 102005020387.6) describes the surface treatment of moldings made of modified wood or modified wood materials or other materials from modified Lignocellulo- semomaterialien, wherein the modified wood material or the modified material of the lignocellulosic material previously similar to WO 2004 / 033170 and WO 2004/033171 is impregnated with crosslinkable nitrogen compounds and crosslinked.

From PCT / EP2006 / 004019 (older German patent application 102005020386.8) modified wood materials are known, which are impregnated and crosslinked with a reactive composition based on crosslinkable nitrogen compounds, which contains at least one effect substance in dissolved or dispersed form in addition to at least one crosslinkable nitrogen compound.

From PCT / EP2006 / 004016 and PCT / EP2006 / 004014) (older German patent applications 102005020390.6 and 102005020389.2) modified wood materials are known which are impregnated and crosslinked with a reactive composition which contains a dispersed, hydrophobic component in addition to at least one crosslinkable nitrogen compound , From the earlier German patent application PCT / EP2006 / 001979 (DE 102005010042.2) modified wood materials of finely divided wood materials are known in which the finely divided wood material is impregnated with a reactive composition based on crosslinkable nitrogen compounds and subjected to a molding process, carried out at the same time a crosslinking becomes. The crosslinking can also take place before the shaping process.

From the earlier German Patent Application PCT / EP2006 / 001980 (DE 102005010041.4) modified wood materials are known, which have at least one with a carrier or other veneer layers surface-bonded thin veneer layer, wherein the veneer layer impregnated with a reactive composition based on crosslinkable nitrogen compounds, glued and to glued to a veneer.

From the older German patent application PCT / EP2006 / 001980 (DE

No. 102005020388.4) discloses modified wood materials which are impregnated and crosslinked with a reactive composition which comprises a) at least one low molecular weight compound V containing at least two N-bonded groups of the formula CH ₂ OH and / or a 1,2-bishydroxyethane bridging two nitrogen atoms Has -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, the at least one di- or polyhydric aliphatic or cycloaliphatic Group having at least 3 carbon atoms, in particular having 3 to 10 carbon atoms, and / or c) contains a reaction product of a low molecular weight compound V with the polyalkylene ether polyol.

It is an object of the present invention to provide new uses for such modified wood materials.

It has surprisingly been found that the modified wood materials known from the prior art are particularly suitable for the production of articles comprising at least one wood material.

Accordingly, the present invention relates to the use of modified wood materials HW containing at least one crosslinkable nitrogen compound in a crosslinked, wood-dispersed form for the manufacture of articles comprising at least one wood material.

The use of such modified wood materials allows the production of articles with improved mechanical strength and improved weathering properties. Stability, in particular reduced cracking in those areas which are made of the wood material and a reduced susceptibility of these areas for attack with wood-damaging organisms such as wood-destroying fungi.

In particular, the modified wood materials are suitable for making articles made of a plurality of interconnected parts, at least one part made of a modified wood material, because of the reduced swelling / shrinkage behavior of the modified wood Parts are more stable and are exposed to less mechanical stress during weather conditions and can better maintain their function. This is especially true when the parts made of the modified wood material are at least partially non-positively and / or positively, in particular by a non-positive or positive connection with non-positive component connected to each other or with parts made of other materials.

According to the invention, all known from the prior art modified wood materials are suitable which contain at least one crosslinkable nitrogen compound in a crosslinked, distributed in the wood form.

In the context of the present invention, a modified wood material is understood to mean wood, i. Solid wood, as well as a wood-based material, i. a wood material including a veneer material and a wood material made of finely divided wood particles, wherein the wood component contains at least one crosslinkable nitrogen compound in a crosslinked form distributed in the wood. The finely divided wood particles include fibers, chips, strands, chips, chips and the like. A veneer material is in the context of the invention, a wood material having at least one veneer layer. Veneers are flat thin wood materials with thicknesses <5 mm, in particular ≤ 2 mm.

In particular, the wood material is solid wood, i. large format with dimensions in the centimeter or meter range, e.g. Planks, billets, logs, beams or the like.

Crosslinked means that the content of extractable components of the nitrogen compound is not more than 50% by weight based on the total amount of the nitrogen compound contained in the wood. The extractable fraction is determined by the nitrogen content of a modified wood material before and after extraction with hot water. For this purpose, a modified wood material is ground to a wood meal, dried dry and the nitrogen content in the wood determined by elemental analysis. Then a sample of the wood meal is extracted with water at 80 ° C. for 16 h, filtered off, dried again at room temperature and the nitrogen content of the products thus obtained is be determined by elemental analysis. Since unmodified wood itself contains no detectable amounts of nitrogen, the difference between the nitrogen content before and after the extraction directly gives the extractable fraction in%, based on the nitrogen value of the sample before extraction.

Distributed in the wood means that the cross-linked nitrogen compound is more or less evenly distributed over the cross-section of the wood and is located not only on the surface or in cavities of the wood.

The amount of crosslinkable nitrogen compound in the wood is usually at least 0.5 wt .-%, in particular at least 1 wt .-%, often at least 2% by weight and is typically in the range of 1 to 20 wt .-% , often in the range of 2 to 15 wt .-%, calculated as nitrogen and based on the weight of the wood material HW. The nitrogen content can be determined by elemental analysis.

Suitable crosslinkable nitrogen compounds for modifying the wood are α) low molecular weight compounds V which are at least two N-bonded groups of the formula CH ₂ OR, where R is hydrogen or C 1 -C ₄ -alkyl, and / or a 1,2-bishydroxyethane bridging two nitrogen atoms Have -1, 2-diyl group, ß) precondensates of the compound V and

Y) reaction products or mixtures of the compound V with at least one alcohol chosen from -C ₆ -alkanols, C ₂ -C ₆ polyols selected and oligo alkylene glycols.

In the case of the crosslinkable nitrogen compounds used to modify the wood material, i. Compounds V, their precondensates and reaction products, are low molecular weight compounds or oligomers of low molecular weight, which are usually completely dissolved in the aqueous composition used. The molecular weight of the crosslinkable compound is usually below 400 daltons. Due to these properties, it is believed that the crosslinkable nitrogen compounds can penetrate into the cell walls of the wood and, on hardening, improve the mechanical stability of the cell walls and reduce their swelling caused by water.

Examples of crosslinkable nitrogen compounds include, but are not limited to:

1, 3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidin-2-one (DMDHEU), 1, 3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidin-2-one, which is substituted by a C ₁ -C ₆ - Alkanol, a C ₂ -C ₆ polyoxy or an oligoalkylene glycol is modified (modified DMDHEU or mDMDHEU), 1, 3-bis (hydroxymethyl) urea, 1, 3-bis (methoxymethyl) 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, low molecular weight melamine-formaldehyde resins (MF resins) such as poly (hydroxymethyl) melamine with at least 2, for example 2, 3, 4, 5 or 6 N-hydroxymethyl groups such as 3-methylolated melamine (= 2,4,6-tris- (N-hydroxymethylamino) -1, 3,5-triazine and low molecular weight melamine-formaldehyde resins (MF resins) such as poly (hydroxymethyl) melamine with at least 2, eg 2, 3, 4, 5 or 6 N- hydroxymethyl groups, the ₆ alkanol, a C ₂ -C ₆ -polyol or an oligoalkylene modified with a -C (modified MF resins).

Aqueous compositions of compounds V, their precondensates and their reaction products are known per se, for example from WO 2004/033171, WO 2004/033170, 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 references cited therein, US 2,731,364, US 2,930,715, H. Diem et al. "Amino-Resins" Chap. 7.2.1 and 7.2.2 in Ullmann's Encyclopaedia of Industrial Chemistry, 5th Ed. on CD-ROM, Wiley-VCH, Weinheim 1997 and literature cited therein, Houben-Weyl E20 / 3, pp. 181 1-1890, and are commonly used as crosslinkers for textile finishes. Reaction products of N-methylolated urea compounds V with alcohols, eg. B. modified 1, 3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidinon-2 (mDMDHEU) are known for example from US 4,396,391 and WO 98/29393. Incidentally, compounds V and their reaction products and precondensates are commercially available, for example under the trade names Fi- xapret® CP and Fixapret® ECO from BASF Aktiengesellschaft, the Luwipal® and the Kauramin® brands (for example Kauramin 650 powder) from BASF.

In a preferred embodiment of the invention, the crosslinkable nitrogen compound is urea compounds which on each nitrogen atom are each an N-bonded group of the formula CH ₂ OR, where R is hydrogen or C 1 -C ₄ -alkyl, and / or a bridging two nitrogen atoms , 2-bishydroxyethane-1, 2-diyl group, and the reaction products of these urea compounds with a dC ₆ alkanol, a C ₂ -C ₆ -POIyl and / or a polyalkylene glycol selected. Preferred among these are 1 3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidin-2-one and with a CrC ₆ alkanol, a C ₂ -C ₆ -polyol and / or a polyalkylene glycol-modified 1, 3-bis ( hydroxymethyl) -4,5-dihydroxyimidazolidin-2-one. Beispie- Ie for polyalkylene glycols are in particular the below-mentioned oligo- and poly-C ₂ - C ₄ -alkylene glycols.

MDMDHEU reaction products of 1, 3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidin-2 with a dC ₆ alkanol, a C ₂ -C ₆ polyol, an oligoethylene glycol or mixtures of these alcohols. Suitable Ci _-6 alkanols are for example methanol, is ethanol, n-propanol, iso-propanol, n-butanol and n-pentanol, preferably methanol. Suitable polyols are ethylene glycol, diethylene glycol, 1, 2 and 1, 3-propylene glycol, 1, 2, 1, 3, and 1, 4-butylene glycol and glycerol. Examples of suitable polyalkylene glycols are, in particular, the following oligo- and

Poly-C ₂ -C ₄ -alkylene glycols. To produce mDMDHEU, DMDHEU are mixed with the alkanol, the polyol or the polyalkylene glycol. Here, the monohydric alcohol, the polyol, or the oligo- or polyalkylene glycol are usually used in a ratio of 0.1 to 2.0, in particular 0.2 to 2 molar equivalents, based on DMDHEU. The mixture of DMDHEU, the polyol or the polyalkylene glycol is usually reacted in water at temperatures of preferably 20 to 70 ° C and a pH of preferably 1 to 2.5, wherein the pH after the reaction usually to a Range is set from 4 to 8.

In a further preferred embodiment of the invention, the crosslinkable

Nitrogen compound under at least 2-fold, for example, 2-, 3-, 4-, 5- or 6-fold, in particular a 3- to 5-fold methylolated melamine and especially a 3-fold or 4-fold methylolated melamine (poly (hydroxymethyl melamine) or a mixture thereof. Equally suitable are partially or completely etherified methylolated melamines this deriva- te, for example, those with a dC ₆ alkanol, especially methanol, C ₂ -C ₆ -polyol and / or a polyalkylene glycol are modified, as well as mixtures thereof with the unmodified melamine compounds , Examples of polyalkylene glycols are, in particular, the oligo- and poly-C ₂ -C ₄ -alkylene glycols mentioned below.

The aqueous compositions usually used for the modification may also contain one or more of the abovementioned alcohols, C ₁ -C ₆ -alkanols, C ₂ -C ₆ -polyols, oligo- and polyalkylene glycols or mixtures of these alcohols. Suitable Ci _-6 alkanols are for example methanol, is ethanol, n-propanol, iso-propanol, n-butanol and n-pentanol, preferably methanol. Suitable polyols are ethylene glycol, diethylene glycol, 1, 2 and 1, 3-propylene glycol, 1, 2, 1, 3, and 1, 4-butylene glycol and glycerol. Suitable oligo- and polyalkylene glycols are, in particular, oligo- and poly-C ₂ -C ₄ -alkylene glycols, especially homo- and cooligomers of ethylene oxide and / or propylene oxide, optionally in the presence of low molecular weight starters, for example aliphatic or cycloaliphatic polyols having at least 2 OH Groups such as 1, 3-propanediol, 1, 3- and 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, glycerol, trimethyl lolethane, trimethylolpropane, erythritol, and pentaerythritol, and also pentites and hexites such as ribitol, arabitol, xylitol, dulcitol, mannitol and sorbitol, and inositol or aliphatic or cycloaliphatic polyamines having at least 2-NH ₂ groups such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, propylenediamine -1, 3, dipropylenetriamine, 1, 4,8-triazaoctane, 1,5,8,12-tetraazadodecane, hexamethylenediamine, dihexamethylenetriamine, 1,6-bis (3-aminopropylamino) hexane, N-methyldipropylenetriamine or polyethers. Thylenimine are available, among which diethylene glycol, triethylene glycol, di-, tri- and tetrapropylene glycol and low molecular weight Pluronic® brands of BASF (eg Pluronic® PE 3100, PE 4300, PE 4400, RPE 1720, RPE 1740) are preferred.

If present, the concentration of the crosslinkable nitrogen compounds in the aqueous composition is usually in the range 1 to 60 wt .-%, often in the range of 10 to 60 wt .-% and in particular in the range of 15 to 50 wt .-%, based on the total weight of the composition. If the aqueous composition contains one of the abovementioned alcohols, its concentration is preferably in the range from 1 to 50% by weight, in particular in the range from 5 to 40% by weight. The total amount of crosslinkable compound and alcohol is usually from 10 to 60% by weight, and more preferably from 20 to 50% by weight, of the total weight of the aqueous composition.

In general, the aqueous composition used for the modification contains at least one catalyst K, which causes the crosslinking of the nitrogen compound. In general, as catalysts K metal salts from the group of metal halides, metal sulfates, metal nitrates, metal phosphates, Metalltetrafluoroborate; boron trifluoride; Ammonium salts from the group of ammonium halides, ammonium sulfate, ammonium oxalate and diammonium phosphate; and organic carboxylic acids, organic sulfonic acids, inorganic Brönsted acids such as boric acid, phosphoric acid, sulfuric acid and hydrochloric acid.

Examples of metal salts suitable as catalysts K are, in particular, magnesium chloride, magnesium sulfate, zinc chloride, lithium chloride, lithium bromide, aluminum chloride, aluminum sulfate, zinc nitrate and sodium tetrafluoroborate.

Examples of ammonium salts suitable as catalysts K are, in particular, ammonium chloride, ammonium sulfate, ammonium oxalate and diammonium phosphate.

Particularly suitable as catalysts K are water-soluble organic carboxylic acids such as maleic acid, formic acid, citric acid, tartaric acid and oxalic acid, furthermore benzenesulfonic acids such as p-toluenesulfonic acid, but also inorganic Bronsted acids such as hydrochloric acid, phosphoric acid, sulfuric acid, boric acid or mixtures thereof. Preferably, the catalyst K is selected from magnesium chloride, zinc chloride, magnesium sulfate, aluminum sulfate or mixtures thereof, magnesium chloride being particularly preferred.

The catalyst K will usually be added to the aqueous composition shortly before the modification process. It is usually used in an amount of 1 to 20 wt .-%, in particular 2 to 10 wt .-%, based on the total weight of the curable components contained in the aqueous composition. The concentration of the catalyst, based on the total weight of the aqueous dispersion, is usually in the range of 0.1 to 10 wt .-% and in particular in the range of 0.5 to 5 wt .-%.

Furthermore, the composition used to modify the wood may contain one or more effect substances, for example a colorant, e.g. a dye or a pigment, a UV stabilizer, an antioxidant, a fungicide and / or insecticide and the like, as described in PCT / EP2006 / 004019 (earlier German patent application 102005020386.8), the contents of which are hereby incorporated by reference. Depending on the effect substance, the concentration of effect substance is in the range from 0.01 to 60% by weight and in particular from 0.1 to 25% by weight, based on the weight of the composition.

Furthermore, the composition used for modifying the wood may contain one or more hydrophobic constituents, for example a wax or an oil in emulsified or suspended form, as in PCT / EP2006 / 004014 and US Pat

PCT / EP2006 / 004016 (older German patent applications DE 102005020389.2 and DE 102005020390.6), the contents of which are hereby incorporated by reference. The concentration of hydrophobic ingredient is typically in the range of 0.01 to 60 weight percent, and more preferably 0.1 to 25 weight percent, based on the weight of the composition.

The modified wood materials and the articles produced therefrom may comprise a conventional coating, for example a lacquer, a glaze or a stain, as described in PCT / EP2006 / 004020 (DE 102005020387.6), the content of which is hereby incorporated by reference.

The preparation of the modified wood materials can be carried out according to the methods described in the cited prior art, to which reference is also made. In general, the production of the modified wood material in the case of solid wood comprises: a) impregnating solid wood with an aqueous composition which contains at least one crosslinkable nitrogen compound and at least one crosslinking catalyst, and b) treating the product obtained in step a ) impregnated solid wood at elevated temperature with removal of water.

In general, the production of a modified wood-based material comprises the steps described in PCT / EP2006 / 001979 (DE 102005010042.2): a) impregnating a finely divided wood material with an aqueous composition containing at least one crosslinkable nitrogen compound and at least one crosslinking catalyst, and b) treating the impregnated wood material obtained in step a) at elevated temperature to remove water. c) gluing and shaping the finely divided wood material obtained in step b) or b) gluing the impregnated wood material obtained in step a) optionally after drying and c ') shaping the wood material at elevated temperature with removal of water to obtain a wood material.

In general, the production of a modified veneer material comprises the steps described in PCT / EP2006 / 001980 (DE 102005010041.4): a) impregnating a veneer with an aqueous composition containing at least one crosslinkable nitrogen compound and at least one crosslinking catalyst, and b) gluing the impregnated veneer with a sizing composition, and c) processing the glued veneer into a veneer material at elevated temperature to cure the crosslinkable nitrogen compound,

The impregnation can be carried out in a conventional manner, for example by immersion, by the application of vacuum, optionally in combination with pressure or by conventional application methods such as brushing, spraying and the like. The particular impregnation method used naturally depends on the dimensions of the material to be impregnated. Small-sized wood materials such as shavings or strands and thin veneers, ie materials with a high surface-to-volume ratio, can be impregnated with little effort, for example by dipping or spraying, whereas wood materials of larger dimensions, especially materials, whose smallest extent exceeds 5 mm, eg solid wood, molded parts made of solid wood or wood materials, using pressure or vacuum, in particular by combined use of pressure and vacuum impregnated. Advantageously, the impregnation is carried out at a temperature below 50 ° C, for example in the range of 15 to 50 ° C.

The conditions of the impregnation will generally be chosen so that the absorbed amount of curable components of the aqueous composition is at least 1 wt .-%, based on the dry weight of the untreated material. The amount of curable ingredients taken up may be up to 100% by weight, based on the dry weight of the untreated materials, and is often in the range of 1 to 60% by weight, preferably in the range of 5 to 50% by weight, and in particular in the range of 10 to 30 wt .-%, based on the dry weight of the untreated material used, is. The moisture content of the impregnated, untreated materials is not critical and can be, for example, up to 100%. Here and below, the term "moisture" is synonymous with the term residual moisture content according to DIN 52183. It is often in the range of 1 to 80% and in particular 5 to 50%.

For dipping, the wood material, optionally after predrying, is dipped in a container containing the aqueous composition. The dipping is preferably carried out over a period of a few seconds to 24 h, in particular 1 min to 6 h. The temperatures are usually in the range of 15 ° C to 50 ° C. Here, the wood material absorbs the aqueous composition, whereby the concentration of the non-aqueous constituents (ie curable constituents) in the aqueous composition, the temperature and the duration of the treatment can control the amount of these constituents taken up by the wood material , The quantity of constituents actually absorbed can be determined and controlled by the skilled person in a simple manner via the weight increase of the impregnated material and the concentration of the constituents in the aqueous composition.

The impregnation is advantageously carried out by combined use of reduced and elevated pressure. For this purpose, the wood material, which generally has a humidity in the range of 1% to 100%, first under reduced pressure, which is often in the range of 10 to 500 mbar and in particular in the range of 40 to 100 mbar, with the aqueous composition brought into contact, z. By immersion in the aqueous composition. The time period is usually in the range of 1 minute to 5 hours. This is followed by a phase at elevated pressure, z. B. in the range of 2 to 20 bar, in particular 4 to 15 bar and especially 5 to 12 bar, to. 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 wood material absorbs the aqueous composition, whereby the concentration of the non-aqueous aqueous components (ie curable constituents) in the aqueous composition, by the pressure, by the temperature and by the treatment time, the amount of these constituents taken up by the wood material can be controlled. The actual amount absorbed can also be calculated here by the weight added of the wood material.

Furthermore, impregnation may be by conventional methods of applying liquids to surfaces, e.g. by spraying or rolling or brushing. For this purpose it is advantageous to use 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 is usually carried out at temperatures in the range of 15 to 50 ° C. The spraying can be carried out in a conventional manner in all suitable for spraying of flat or finely divided bodies devices, for. B. by means of nozzle arrangements and the like. When brushing or rolling the desired amount of aqueous composition is applied with rollers or brushes on the sheet materials.

Subsequently, in step b), the curing of the crosslinkable constituents of the aqueous composition takes place. Curing can be carried out in analogy to the methods described in the prior art. e.g. according to the methods described in WO 2004/033170 and WO 2004/033171.

Curing is typically carried out by treating the impregnated material at temperatures above 80 ° C, especially above 90 ° C, e.g. in the range of 90 to 220 ° C and in particular in the range of 100 to 200 ° C. The time required for curing is typically in the range of 10 minutes to 72 hours. Veneers and finely divided wood materials tend to use higher temperatures and shorter times.

If appropriate, a drying step, also referred to below as a predrying step, can be carried out before curing. In this case, the volatile constituents of the aqueous composition, in particular the water and excess organic solvents, which do not react in the curing / crosslinking of the urea compounds, partially or completely removed. Predrying means that the wood body is dried below the fiber saturation point which, depending on the type of wood, is about 30% by weight. This predrying counteracts the risk of cracking. For small-sized wood bodies, such as veneers, the pre-drying can be omitted. For wood bodies with larger dimensions, however, the predrying is beneficial. If a separate pre-drying is carried out, this is advantageously carried out at temperatures in the range of 20 to 80 ° C. Depending on the selected drying temperature, a partial or complete hardening tion / crosslinking of the curable components contained in the composition. The combined predrying / curing of the impregnated materials is usually carried out by applying a temperature profile, which may range from 50 ° C to 220 ° C, in particular from 80 to 200 ° C.

The curing / drying can be done in a conventional fresh air exhaust system, eg. B. a drum dryer, performed. Pre-drying preferably takes place in such a way that the moisture content of the finely divided lignocellulosic materials after predrying is not more than 30%, in particular not more than 20%, based on the dry mass. It may be advantageous to carry out the drying / curing up to a moisture content <10% and in particular <5%, based on the dry mass. The moisture content can be easily controlled by the temperature, the duration and the pressure selected during pre-drying.

Optionally, one will remove by mechanical means adhering liquid before drying / curing.

For large format materials, it has been found useful to fix them during drying / curing, e.g. in heating presses.

The wood materials impregnated in step a), if they are finely divided materials or veneer layers, can be further processed in a manner known per se, in the case of finely divided materials, e.g. shaped articles such as OSB (oriented structural board), chipboard, wafer boards, OSL boards or Oriented Strand Lumber (OSL) molded parts, PSL boards or PSL (parallel beach lumber) molded parts .

Constructed Strand Lumber panels, structural composite lumber (SCL) panels, Laminated Strand Lumber (LSL) panels, insulating panels, and medium density (MDF) and high density (HDF) fiberboard and the like, in the case of Veneering to veneer materials such as veneered fiberboard, veneered blockboard, veneered chipboard including veneered OSB, SCL,

OSL and PSL boards, plywood, laminated wood, plywood, laminated veneer lumber (eg Kero plywood), multiplex boards, laminated veneer lumber (LVL), as well as non-flat, 3-dimensional parts such as plywood parts , Plywood moldings and any other molded parts coated with at least one veneer layer. The further processing can take place immediately after the impregnation in step a), during or after the curing in step b). For veneers and wood-based materials, further processing includes not only curing and gluing, but also forming a gluing step. For details, reference is made to the content of PCT / EP2006 / 001980 (DE 102005010041.4 Fur- nierwerkstoffe) and the contents of PCT / EP2006 / 001979 (DE 102005010042.2 wood materials). In the case of impregnated veneers, it is advantageous to Properly perform the further processing before the curing step or together with the curing step. For wood materials made of finely divided materials, the shaping step and the curing step are often carried out simultaneously.

In principle, all types of wood are suitable for the production of modified wood materials, preferably those which can absorb at least 30%, in particular at least 50% of their dry weight of water, and particularly preferably those which are classified in the impregnability classes 1 and 2 according to DIN EN 350-2. These include, for example, woods of conifers such as pine (Pinus spp.), Spruce, Douglas fir, larch, pine, fir, coastal fir, cedar, stone pine, as well as deciduous trees, eg. Eg 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. Since the impregnation achieves intrinsic shadows even in low-cost woods, such as otherwise only tropical woods, for example an extremely low swelling / shrinking behavior, high strengths and good weathering stability, a particular embodiment of the invention relates to the use of modified wood or wood Wood material whose wood constituent is selected from beech, spruce, pine, birch, poplar, ash and maple.

As already explained above, wood materials modified according to the invention are particularly suitable for the production of articles which comprise a plurality of interconnected parts, wherein at least one part is made of a modified wood material HW.

They are particularly suitable for the production of articles, wherein at least two parts of the article are connected to each other by a frictional connection, wherein at least a part of the mutually positively connected parts is made of a modified wood material HW. In particular, they are also suitable for the production of articles in which at least two parts of the article are connected to one another by a form-locking connection, in particular a positive connection with non-positive component, wherein at least a part of the parts joined together in a form-fitting manner is made of a modified wood material HW ,

Of course, the positive or non-positive connections can also be supported by cohesive connection means, e.g. through a sizing.

Examples of frictional connections or positive connections with non-positive component are bolted and nailed connections, tapped connections and tongue and groove connections, furthermore marked connections, a finally finger tines, half-concealed zincing, open zincing (dovetail joints), miter tine and finger tap, claw connection, burrs, comb connections, doweled joints, and other, not usual in wood construction, non-material connections.

In particular, because of its insensitivity to moisture, the invention also relates to the use of modified wood materials for the manufacture of articles exposed to moisture or weather conditions. The influence of moisture may be a contact with high humidity, e.g. when the objects are in wet rooms such as bathrooms, indoor swimming pools, laundry rooms, inside ships, and the like, or even if they are exposed outdoors in high humidity. The moisture contact may also be contact with liquid water or with standing moisture, e.g. by the action of rain, by contact with river or lake water in structures of hydraulic engineering or ships.

The objects can be produced in a manner known per se in analogy to the production of articles from wood materials. It includes typical woodworking operations such as sawing, cutting, planing, milling, grinding, drilling, screwing, nailing, gluing, laminating and the like. As a rule, in the production of the articles, one already starts from the modified wood material. But you can also first make the article of an unmodified wood material and then subject the wood components of a modification, as described above.

In a first embodiment of the invention, the modified wood material is used for the production of floor coverings. Often veneer materials are used in which the decorative, weathering or mechanical stress exposed surface is formed by a layer of veneer layer modified according to the invention. One example of this is parquet, including parquet flooring, solid parquet, mosaic parquet, vertical edged parquet, pre-finished parquet, eg 2-ply or 3-ply parquet flooring, veneer flooring and sports flooring, eg elastic sport floors and point elastic sports floors, as well as parquet swinging floors. Wood materials modified according to the invention are also suitable for the production of plank parquet, terrace coverings and the like. Inventive wood materials are also suitable for the production of laminate, wherein the wood material modified according to the invention generally forms the press-wood layer of the laminate. A specific embodiment of the invention relates to a floor covering material for the outer and wet areas. Conventional outdoor and wet flooring materials are typically hardwood planks, planks or boards that are often patterned with surface texture. These floor coverings are usually very expensive due to the high price of hardwoods. The weather or moisture resistance is not always satisfactory. The wood materials of the invention now allow the production of floor coverings with high durability even from inexpensive woods such as pine, spruce, beech, poplar and the like. In particular, the wood materials according to the invention allow the production of floor covering materials comprising a carrier layer of a first wood material according to the invention and a cover layer or wear layer made of a second, wood material connected to the carrier material, in particular glued or glued. The material of the carrier layer is typically a wood material according to the invention of a low-cost type of wood, in particular an inexpensive solid wood, for example a pine wood treated according to the invention. The wood material of the wear layer is preferably also a wood material according to the invention, preferably a wood material according to the invention with a decorative appearance, for example beech treated according to the invention. However, the wear layer can also be made from an untreated or a hardwood treated according to the invention, for example Durability Classes 1 or 1 such as Angelim, Bangkirai, Bongossi, Bilinga, Cumaru, Douglas Fir, Eucalyptus, Fava, Garapa, Ipe, Iroko, Itauba, Jatoba, Karri , Limbali, Massaranduba, Mukulungu, Okan, Piquia, Robinie, Taii, Tatajuba, Torrado or Teak. The useful layer typically has a thickness (thickness) of at least 1 mm, for example 1 to 10 mm, in particular 2 to 8 mm. The wear layer may have a profiling, eg a groove profile. The thickness of the carrier layer naturally depends on the desired application and the strength required for this purpose. It is typically in the range of 5 to 100 mm, in particular in the range of 10 to 50 mm. The floor coverings can be in the form of boards, boards, planks, planks or gratings. The floor coverings may comprise means for connecting the individual elements of the floor covering, for example tongue and groove connections, click connections and the like. The production of such floor coverings is typically carried out by gluing or bonding the carrier layer to the wear layer in analogy to known methods for gluing wood layers, for example analogously to methods for the production of ply woods or for the production of floor coverings for the interior, a carrier layer and one thereon have arranged wear layer. In particular, the preparation can be carried out in analogy to the method described in PCT / EP2006 / 001980, wherein unlike the method described therein according to the invention treated wood materials are glued or glued together.

In a further embodiment of the invention to use the modified wood material for the production of doors and door frames, for example, for interior doors but also for house doors. The modified wood material can be used both for the door leaf itself, for parts of the door leaf, for example in the form of solid wood or wood-based panels for the inner structure of the door leaf or in the form of a veneer for the decorative layer on the door panel are used.

In another embodiment of the invention, the modified wood material is used to make windows, e.g. of window frames and / or casements. The window frames and casements can be made of the same wood but also of different types of wood. It is also possible that the frame is made of a different material from wood and only the sash are made of a modified wood material according to the invention. The wood materials modified according to the invention can also be used for the production of window sills.

In a further embodiment of the invention, the modified wood material is used for the production of furniture, in particular of furniture or furniture parts which are typically made of wood or wood materials. These include cabinets or parts of cabinets such as the body, the doors or floors, shelves, bed frames, slatted frames, Sofagestelle, chairs, tables, or parts of this furniture such as table bases, table tops, countertops, especially kitchen countertops, bathroom furniture and the like. The wood materials modified according to the invention are particularly suitable for furniture that is more exposed to moisture or weathering, e.g. for the manufacture of kitchen furniture, bathroom furniture or for the production of garden furniture, park benches, stadium seats and the like.

In a further embodiment of the invention, the modified wood material is used to make articles for hydraulic engineering, e.g. for bank attachments, hydraulic structures such as locks, in particular floodgates, water wheels, platforms, pontoons, footbridges and other constructions in and on the water.

In a further embodiment of the invention, the modified wood material is used for the construction of buildings or parts of buildings. In addition to the previously mentioned window construction, these include in particular the use of modified wood materials in the form of construction timbers for the construction of wooden houses, for timber framing, for the construction of roof structures, for buildings in wooden stand construction, for the construction of bridges or viewing platforms, carports and for Building parts such as terraces, balconies, balcony railings, dormers and the like. This also includes the use of modified wood materials for the construction of stairs including stairs, eg for wooden steps in metal stair structures, but also for completely made of wood materials stairs and railings. In a further embodiment of the invention, the modified wood material for facade construction is used. The modified wood material can be both part of the facade substructure and form the visible part of the facade, for example in the form of facade panels made of the modified wood material, facade boards made of modified wood, shingles made of modified wood and the like.

In a further embodiment of the invention, the modified wood material is used for the production of wall elements and ceiling elements, for example panels, tongue-and-groove boards, cassette ceilings, but also ceiling suspensions, mobile walls or wall elements in column construction, ceilings and wall coverings. Wood-based materials based on finely divided materials in the form of sheets are particularly suitable for this purpose, for example OSB boards, chipboards, OSL boards, PSL boards, insulating boards and medium-density (MDF) and high-density (HDF) fiber boards and the like, and veneer materials such as veneered fiber boards. veneered blockboard, veneered chipboard including veneered OSL and PSL boards, plywood, laminated wood, laminated wood, laminated veneer lumber (eg Kerto plywood).

In a further embodiment of the invention, the modified wood material used for horticulture, for example for the production of fences, palisades, privacy screens, garden sheds, pergolas, birdhouses and the like.

In a further embodiment of the invention, the modified wood material is used for the production of outdoor play equipment, for example climbing frames, swings, in particular rocking scaffolds and swing seats and boards, play landscapes with climbing, rocking and / or sliding devices, for cableway scaffoldings and the same.

In a further embodiment of the invention, the modified wood material is used for the production of household articles, for example for knife blocks, bread boxes, wooden bowls, bathing accessories such as bath tubs, brushes and the like, furthermore for cutting boards, cooking utensils such as cooking spoons, spatulas, rolling pins, salad servers, pasta forks and the like ,

In a further embodiment of the invention, the modified wood material used for boat building, both for the construction of hulls, eg for the planking, for ribs and keel, engine mounts, for stationary goods such as masts, spars, but also for deck superstructures, Decksbeplankung and other external devices such as gratings, cleats, rowing wheel, instrument panels, and the like, as well as for the interior fittings of ships eg for cabinet installations, berth installations, cabin walls and doors, engine cowlings, companionways, ladders and the like.

In a further embodiment of the invention, the modified wood material is used for sauna construction, for example for walls, doors, benches, oven linings and the like.

In a further embodiment of the invention, the modified wood material used in vehicle construction, for example, for interior trim of the passenger compartment, the trunk and engine compartment linings, further insulation, such as the engine compartment and the trunk, continue for dashboards Holzdekors and the like.

In a further embodiment of the invention, the modified wood material is used for the manufacture of toys such as building blocks, ball tracks, toy houses and toy furnishings such as dollhouses, doll kitchens and the like, toy cars, airplanes and ships, for model making such as model cars, aircraft and ships, play equipment such as rackets, rackets and the like.

In a further embodiment of the invention, the modified wood material is used for the production of musical instruments, in particular for the construction of stringed instruments such as guitars, lutes, harps, violins, violas, cellos, double basses or parts thereof such as bridge, carcass, snail, whirl, for the construction of woodwind instruments such as clarinets, oboes, bassoons, recorders etc.

In a further embodiment of the invention, the modified wood material is used for the production of sports equipment, in particular such sports equipment, which are typically made of wood or wood materials, but also for sports equipment in which wood for reasons of its lack of strength and hardness has not been used. Examples include rackets, such as hockey and ice hockey sticks, throwing equipment such as spears and discus, rudders and skulls, for the construction of sports couriers such as skull boats, kayaks, one, Canadians, gigs and the like.

In a further embodiment of the invention, the modified wood material is used for the manufacture of housings including housing parts for machines, electrical appliances and the like.

Due to the increased strength of the modified wood materials according to the invention can be in many cases a weight savings by reducing the cost of materials to reach. In addition, the objects are far less susceptible to the weather and the influence of moisture. Due to the high dimensional stability due to the low swelling and shrinkage and the resulting manufacturing tolerances, the modified wood material can also be used for the production of objects in which so far wood could not be used.

Impregnating wood materials

Preparation Example 1 DMDHEU (imDMDHEU) modified with diethylene glycol and methanol was added

30 wt .-% diluted with water and mixed with 1, 5 wt .-% MgCl ₂ x 6 H ₂ O mixed. Pinewood boards with dimensions of 15O x 10 x 2.5 cm, dried to approx. 12% moisture content, were placed in an impregnation system. In the impregnation plant, a vacuum of 40 mbar (absolute) was applied for 30 minutes. Subsequently, the impregnation plant was flooded with the impregnating agent. The vacuum of absolutely 50 mbar was kept constant. Subsequently, a pressure of 10 bar was applied for 2 hours. The printing phase was stopped and the residual liquid was removed. The wooden boards were then stored in a controllable over temperature and humidity drying chamber and fixed so that discarding was impossible. The chamber was brought to 120 ° C and a relative humidity of about 95%. These humid conditions were kept until a temperature of at least 120 ° C was reached within the wood body for 48 hours.

The subsequent drying of the wooden bodies was carried out on a well ventilated wooden stack.

The boards thus obtained can be further processed into any objects, e.g. to tongue-and-groove planks.

Production Example 2

The preparation of impregnated pine boards was carried out analogously to Preparation Example 1, using the following impregnating agent instead of the impregnating agent used there: Mixture obtainable by diluting a commercially available, aqueous preparation of 1,3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidine 2-one

(DMDHEU) with water to a concentration of 30 wt .-% and dissolving 15 g / kg MgCl ₂ x 6 H ₂ O in the mixture.

Production Example 3 The preparation of impregnated pine boards was carried out analogously to Preparation Example 1, wherein instead of the impregnating agent used there, the following impregnating agent was used: Mixing of 2.5 kg of a commercial, aqueous preparation of 1, 3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidin-2 on (75 wt .-%) with 2 kg of a commercial, 70 wt .-%, aqueous solution of a reaction product of melamine with formaldehyde and methanol (molar ratio 1: 4: 4) and 200 g of MgCl ₂ x 6 H ₂ O. and diluting the resulting mixture with 5.2 kg of water.

Production Example 4

In an analogous manner to Production Example 1, beech strips and beech boards were treated.

The thus obtained beechwoods were further processed into garden furniture, namely garden tables, garden chairs and garden benches, each having a plurality of gezapter compounds and / or gezinkter compounds.

Even after several months of outdoor weathering, the garden furniture did not show any appreciable visual changes or damage to the joints of the woods.

Production Example 5:

In analogy to Preparation Example 1, pine beams and pine boards were treated.

The pinewood obtained in this way was further processed into Euro pallets. Even after several months of outdoor weathering, the europallets showed no noticeable visual changes.

Production Example 6:

In an analogous manner to Preparation Example 1, pine beams and corrugated boards made of pine wood (pine boards whose one surface was provided with longitudinal corrugation) were treated.

The pine beams thus obtained were screwed with the ribbed boards to a terrace covering. Even after several months of outdoor weathering, the terrace covering showed no appreciable optical changes.

Claims

claims

1. Use of modified wood materials HW containing at least one crosslinkable nitrogen compound in a crosslinked, distributed in wood form, for the production of articles comprising at least one wood material.

2. Use according to claim 1, wherein the modified wood material HW contains the nitrogen compound in an amount of at least 1 wt .-%, calculated as nitrogen and based on the weight of the modified wood material HW.

3. Use according to one of the preceding claims, wherein the crosslinkable nitrogen compound is selected from:

1, 3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidin-2-one,

1, 3-bis (hydroxymethyl) -4,5-dihydroxyimidazolidin provided with a CrC ₆ - is modified alkanol, a C ₂ -C ₆ -polyol or an oligoalkylene glycol,

1, 3-bis (hydroxymethyl) urea,

1, 3-bis (methoxymethyl) urea;

1-hydroxymethyl-3-methylurea,

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, low molecular weight melamine-formaldehyde resins and - low molecular weight melamine-formaldehyde resins containing a CrC ₆ -

Alkanol, a C ₂ -C ₆ -PoIyOl or a Oligoalkylenglykol are modified

(modified MF resins).

4. Use according to one of the preceding claims, wherein the modified wood material HW is a modified solid wood.

5. Use according to one of the preceding claims, wherein the modified wood material HW is a modified wood material.

6. Use according to any one of the preceding claims, wherein the article comprises a plurality of interconnected parts, wherein at least a part made of a modified wood material HW is made.

7. Use according to claim 6, wherein at least two parts of the article are non-positively connected with each other, wherein at least a part of the mitein- other non-positively connected parts made of a modified wood material HW is made.

8. Use according to one of the preceding claims, wherein the wood constituent part of the modified wood material HW is a wood which, according to DIN EN

350-2 is classified in the drenchability class 1 or 2.

Use according to any one of the preceding claims for the preparation of articles exposed to moisture or weather conditions.

10. Use according to one of the preceding claims for the production of floor coverings.

1 1. Use according to one of claims 1 to 9 for the production of doors and door frames.

12. Use according to one of claims 1 to 9 for the manufacture of windows.

13. Use according to one of claims 1 to 9 for the manufacture of furniture.

14. Use according to one of claims 1 to 9 for the production of articles for hydraulic engineering.

15. Use according to one of claims 1 to 9 for the construction of buildings or parts of buildings.

Use according to claim 15, wherein the modified wood material is a construction wood.

17. Use according to claim 15 for the construction of stairs and railings.

18. Use according to claim 15 for facade construction.

19. Use according to one of claims 1 to 9 for the production of wall elements and ceiling elements.

20. Use according to one of claims 1 to 9 for horticulture.

21. Use according to one of claims 1 to 9 for the production of Spielge- rates for the outdoor area.

22. Use according to one of claims 1 to 9 for the production of household items.

23. Use according to one of claims 1 to 9 for boat building.

24. Use according to one of claims 1 to 9 for the sauna.

25. Use according to one of claims 1 to 9 in vehicle construction.

26. Use according to one of claims 1 to 9 for the production of toys.

27. Use according to one of claims 1 to 9 for the production of musical instruments.

28. Use according to one of claims 1 to 9 for the production of sports equipment.

29. Use according to one of claims 1 to 9 for the production of housings sen.