NL2004189C2

NL2004189C2 - Method and apparatus for modifying wood, and wood product.

Info

Publication number: NL2004189C2
Application number: NL2004189A
Authority: NL
Inventors: Wilhelmus Petrus Martinus Willems
Original assignee: Via Ingenio B V
Priority date: 2010-02-04
Filing date: 2010-02-04
Publication date: 2011-08-08
Also published as: WO2011096812A1

Abstract

The invention relates to a method for modifying wood. The invention also relates to a wood product. The invention further relates to an apparatus for performing the method according to the invention. The modification process according to the invention has a relatively short process time, wherein a good modification is realized while the wood is not distorted by stresses and checks.

Description

Method and apparatus for modifying wood, and wood product

The invention relates to a method for modifying wood, in particular to preserve wood and/or to improve the dimensional stability. The invention also relates to a wood 5 product. The invention further relates to an apparatus for performing the method according to the invention.

Upgrading of wood by hydrothermolysis is known. In a hydrothermolysis wood is treated with saturated steam at a temperature between 130-220°C, wherein a 10 hemicellulose and lignin become reactive. In a subsequent step the wood is cooled and cured by drying, wherein the reactive hemicellulose and lignin form cross-links. The final product is wood which has acquired a greater durability and fungal resistance than the untreated wood. Since all that is required for the reaction is water in the form of steam, hydrothermolysis is particularly advantageous compared to preserving methods 15 in which the wood is upgraded with impregnating agents usually having an environmental impact.

Drawbacks of known hydrothermolysis methods are that they are particularly time-consuming. The wood is treated in multiple individual steps with interim cooling and 20 heating of the wood. Time is lost here and the wood is placed under great internal stresses as a result of contraction and expansion, which result in splitting and deformation. This results in high costs due to longer production times on the one hand and to a decrease in the economic value of the wood on the other.

25 More rapid methods of thermal preservation are known, wherein dried wood is heated to very high temperatures above 220 degrees Celsius. The drawback of these rapid methods is however that the mechanical strength of the product decreases very greatly when compared to the starting products. Rapid thermal treatment methods with less high temperatures result in products with a reduced durability when compared to the 30 products at higher temperatures. The known, relatively rapid methods also produce a high percentage of products of low-grade quality due to splitting and deformation.

It is an object of the invention to enable a rapid modification of wood with relatively little loss in mechanical strength.

2

The invention provides for this purpose a method for modifying wood, comprising the processing steps of: A) impregnating wood to be modified with a reactive composition, in particular a polymerisable composition, and B) allowing the impregnated wood to 5 react in a steam filled treatment space by heating the treatment space to a temperature of at least 70 degrees Celsius, after which the temperature in the treatment space is raised gradually with a temperature gradient of a maximum of 40 degrees Celsius per hour, preferably between 20-40 degrees Celsius per hour, to a maximum temperature of between 120 and 220 degrees Celsius; wherein the wood is heated at said maximum 10 temperature during a reaction time of at least 10 minutes. During step B) the composition impregnated in the wood will react chemically in a controlled humid atmosphere, as a result of which the wood will be chemically modified and hence be preserved in a relatively durable manner while the favourable properties of the wood, such as its mechanical strengthness and dimensional stability, will be maintained as 15 much as possible. In case the maximum temperature would exceed 140 degrees Celsius, and would be situated between 140 and 220 degrees Celsius, the wood is modified by both thermally and chemically modifying the wood during the treatment process. In case the maximum temperature would be situated between 120 and 140 degrees Celsius, commonly merely a chemical modification of the wood will be realized. Allowing the 20 wood to react under the influence of heat and in a controlled humid environment, will lead to a controlled modification process of the wood. To this end, the presence of steam, preferably with a controlled humidity, is important to counteract drying out of the wood during the treatment according to the invention as much as possible, which is in favor of the affectivity and the yield of the treatment to obtain modified wood with 25 the desired properties. It is noted that in case no steam would be used during step B) wood would be obtained commonly having poor properties and hence often insufficient quality for further use.

Wood impregnated and reacted (cured) with a reactive composition, in particular a polymerisable composition, in a controlled humid environment according to the 30 invention shows improved properties such as improved durability, dimensional stability and surface hardness. In addition, the obtained wood shows enhanced resistance against degradation by biological organisms, e.g. fungi, without exerting biocidal effects towards such organisms. Furthermore wood modified according to the present invention exhibits enhanced UV stability, cracking resistance, rot resistance and decay resistance.

3

In addition, the present wood shows an increased lifetime, is of a consistent quality. It is further noted that the present wood is environmentally friendly, since wood that has been impregnated and reacted in accordance with the present invention has qualities which are comparable with tropical hard wood, and is therefore an ideal substitute 5 thereof. Also, the present wood does not have toxicity to organisms in the environment, including humans. Even at the end-of-life, toxic compounds are not released from the woods obtained by applying the method according to the invention. Waste of wood components due to damage by for instance splitting is also exceptionally low. The reactive compositions, in particular polymerisable compositions, applied are able to 10 penetrate into the cell structure of wood (step A) and are subsequently polymerized or reacted in another manner in situ (step B). The composition becomes an integral part of the wood cell-wall structure, modifies the wood cell wall and stable impregnated wood is obtained. Preferably, the reactive composition remains stable at increased temperature according to step B) and will not be decomposed due to heating. Different reactive 15 compositions may be used for impregnation during step A), wherein the chemical reaction during the heat treatment according to step B) is dependent on the nature of the reactive composition used. As an example, the following non-limitative reactive compositions may be used in the method according to the invention, wherein the chemical reaction type is indicated in parenthesis: acetic anhydride (acetylation); 20 melamine (melamine resin); (methylated-) dimethyloldihydroxyethyleneurea (DMDHEU); furfurylalcohol (furfurylation); alkoxysilane (silicone/silane); and linseed oil, natural resin, parafin (oil/wax/parafins).

In an embodiment of the method according to the invention, during step B) the relative 25 humidity within the treatment space is held at a substantially constant level, preferably between 65% and 85%, more preferably at (about) 75%. By maintaining the relative humidity within the treatment space at a substantially constant level, the humidity within the wood can be controlled in a satisfying manner, preferably at a substantially constant level, which is in favor of the final quality of the modified wood obtained.

30

In another embodiment of the method according to the invention a water supply container is positioned within the treatment space, wherein during step B) water is evaporated from the water supply container to humidify the treatment space. The quantity of water to be evaporated from the water supply container will commonly be 4 controlled by the temperature within the treatment space and/or the water supply container, wherein the temperature can commonly be regulated by a heating means adapted to heat the treatment space and/or the water supply container. By applying e.g. a temperature sensor and/or a humidity and/or a pressure sensor, connected via a control 5 unit to said heating means, a self-regulating humid microclimate within the treatment space can be established relatively easily.

The manner to impregnate the wood to be modified with a composition in general is known as such. To this end, commonly the wood to be treated is placed in a treatment 10 vessel wherein a vacuum is applied, after which the wood is exposed to the composition while substantially maintaining said vacuum, and wherein a predetermined pressure, commonly of between 8 and 10 bar, is applied to the wood for a period of time sufficient to partially impregnate the wood with the composition. Subsequently, the pressure within the treatment vessel is reduced and the surplus of composition is 15 removed from the treatment vessel. It is conceivable that during step A) the wood is merely partially impregnated by the reactive composition, in particular the polymerisable composition. In this case, an outer shell of the wood may be impregnated, while a core of the wood will remain unimpregnated. Partially impregnating the wood with the reactive composition, in particular the polymerisable 20 composition, will commonly be cheaper than fully impregnating the wood with the reactive composition, in particular the polymerisable composition, due to material savings. However, in this case it is preferred to subject the wood, and in particular the unimpregnated part of the wood, commonly the core of the wood, to a thermal modification treatment at a temperature of between 140 and 220 degrees Celsius, 25 preferably about 190 degrees Celsius. Unwanted reactions can take place in the wood at temperatures above 220 degrees.

In case the wood is impregnated substantially completely with the polymerisable composition, merely a chemical modification at a maximum temperature of between 30 120 and 140 degrees Celsius is commonly required to obtain modified wood with desired properties. Hence, an additional thermal treatment (realized at temperatures above 140 degrees Celsius) is not required, and often even undesired to retain the mechanical strength of the wood as much as possible.

5

During step A) the initial temperature of the wood is normally the ambient temperature, usually between 15 and 25 degrees Celsius. In the starting situation, prior to step A), the wood generally has a moisture content of between 3-18% by weight (of the dry wood mass). Since the reactive composition often comprises a liquid compound, in particular 5 a liquid carrier, the moisture content of the wood will be increased during step A). In case the wood is humidified during step A), it is commonly preferred to reduce the moisture content of the wood to lower values of between 6 and 20% by weight by drying the wetted wood during step C) prior to execution of step B) to enable the existence of a hygroscopic equilibrium between the wood and the environment 10 surrounding the wood, both during and after step B), which will commonly be in favor of a consistent quality of the modified wood obtained.

It is commonly advantageous in case the method further comprises step D) comprising removing at least a substantial fraction of air, in particular oxygen, from the treatment 15 space prior to execution of step B). The removal of air, in particular oxygen, from the treatment space during step D) can for instance take place by displacement of air by an inert gas such as nitrogen or argon, or by steam. If air is not removed, oxygen from the presence air may lead to unwanted reactions during the modification process. The best results are achieved if the oxygen is removed by creating a vacuum in the treatment 20 space. If a vacuum has been created in the treatment space during step D), the steam can be used to supplement the vacuum. Placing the treatment space under reduced pressure (creating a vacuum) is found to be a more rapid and effective method of removing oxygen than other methods, such as displacing air by means of nitrogen or steam. Creating a vacuum moreover simplifies control of the process: the degree of pressure 25 decrease can be determined using a simple pressure gauge and is a reliable measure of the quantity of air, and thereby oxygen, removed. In an embodiment the reduced pressure is lower than 13 kPa. This results in a proper removal of oxygen from the treatment space. During the reduced pressure the wall temperature of the treatment space can optionally be increased to 50-70 degrees Celsius for an even better removal of 30 oxygen. The time required for the process is moreover shortened since a start is already made with pre-heating for the subsequent processing step B).

6

The chemical reaction according to step B) can be stopped by reducing the temperature to below 120 degrees Celsius, and then further to room temperature. The cooling process and conditions are dependent on the reactive composition used.

5 During step B) the heated wood may be compressed in the treatment space to obtain a wood product with a greater density.

It is advantageous if the steam has a maximum degree of saturation of 95% during step C). The degree of saturation is the percentage relative to 100% saturated steam at the 10 same pressure and temperature. This produces a better wood product, and in particular less splitting, than a comparable process in which saturated steam is used. A significant factor here is probably that condensation of water is largely prevented.

During step B) the steam preferably has a pressure of at least 4 bar. Heat and water are 15 transferred rapidly to the wood at such a pressure. Step B) is preferably performed at a steam pressure between 4 and 12 bar.

In an embodiment of the method according to the invention, the reactive substance is formed by a polymerisable substance comprising a chemical compound of formula I 20 and/or formula II

R2\93 r* r6 r5 ,r7 pi pi Ï4 J n

Formula I

r1B R19 r^0>-r-

25 Formula II

7 wherein n is an integer between 0 and 20, preferably between 0 and 10, and more preferably between 0 and 5 wherein t and s each independently are an integer between 1 and 20, preferably between 1 and 10, and more preferably between 1 and 5, wherein w and z each independently are 0 or 1 , wherein X and Y each independently are O, S or 5 N-R21 and wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R18, R19, R21 are each independently hydrogen or selected from the group comprising Ci-C2o alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, C5-C12 heteroaryl, carboxaldehyde, hydroxyl, hydroxyalkyl, carboxyl, amino, nitro, formyl, alkylamino, aminoalkyl, alkylaminoalkyl, furyl, furylalkyl, hydroxyalkylfurylalkyl, alkyloxy, 10 alkoxyalkyl, alkenyloxy, alkylcarbonylalkenyl, oxiranyl, alkylcarbonyloxyalkyl, alkyloxycarbonylalkenyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyl, alkenylcarbonyl, halocarbonyl, haloalkyl, haloaryl, haloalkenyl, imino, thiol, alkylthio, thioalkyl, alkylthioalkyl, cyano, alkylsulfonyl, sulfonic acid, and any mixtures thereof, whereby each group is optionally 15 substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio, wherein R17 and R20 are each independently selected from the group comprising C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, C5-C12 heteroaryl, 20 carboxaldehyde, hydroxyl, hydroxyalkyl, carboxyl, amino, nitro, formyl, alkylamino, aminoalkyl, alkylaminoalkyl, furyl, furylalkyl, hydroxyalkylfurylalkyl, alkyloxy, alkoxyalkyl, alkenyloxy, alkylcarbonylalkenyl, oxiranyl, alkylcarbonyloxyalkyl, alkyloxycarbonylalkenyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyl, alkenylcarbonyl, halocarbonyl, haloalkyl, 25 haloaryl, haloalkenyl, imino, thiol, alkylthio, thioalkyl, alkylthio alkyl, cyano, alkylsulfonyl, sulfonic acid, and any mixtures thereof, whereby each group is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and 30 alkylthio, and wherein the dotted line represents an optional double bond.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art. When describing the compounds used in the method according to the invention, the terms used are to be 8 construed in accordance with the following definitions, unless a context dictates otherwise.

The term "alkyl" by itself or as part of another substituent, refers to a straight or 5 branched saturated hydrocarbon group joined by single carbon-carbon bonds having 1 to 20 carbon atoms, for example 1 to 10 carbon atoms, for example 1 to 8 carbon atoms, preferably 1 to 6 carbon atoms, more preferably 1, 2, 3 or 4 carbon atoms. When a subscript is used herein following a carbon atom, the subscript refers to the number of carbon atoms that the named group may contain. Thus, for example, C1-C4 alkyl means 10 an alkyl of one to four carbon atoms. Examples of alkyl groups are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, 2-methylbutyl, pentyl iso-amyl and its isomers, hexyl and its isomers, heptyl and its isomers and octyl and its isomer. When the term "alkyl" is used as a suffix following another term, as in "hydroxyalkyl," this is intended to refer to an alkyl group, as defined above, being substituted with one 15 or two (preferably one) substituent(s) selected from the other, specifically-named group, also as defined herein. As used herein, the term C1-C20 alkyl refers to an alkyl of 1,2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms.

The term "alkenyl" by itself or as part of another substituent, refers to a straight or 20 branched alkyl chain containing at least one unsaturation in the form of a single carbon to carbon double bond and having 2 to 20 carbon atoms, for example 2 to 10 carbon atoms, preferably 2 to 8 carbon atoms, more preferably 2, 3 or 4 carbon atoms. Examples of alkenyl groups are ethenyl (vinyl), 2-propenyl, 2-butenyl, 3-butenyl, 2-pentenyl and its isomers, 2-hexenyl and its isomers, 2-heptenyl and its isomers, 2-25 octenyl and its isomers, 2,4-pentadienyl and the like. As used herein, the term C2-C20 alkenyl refers to an alkenyl of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms.

The term "alkynyl" by itself or as part of another substituent, refers to a straight or 30 branched alkyl chain containing at least one unsaturation in the form of a single carbon to carbon triple bond and having 2 to 20 carbon atoms, for example 2 to 10 carbon atoms, preferably 2 to 8 carbon atoms, more preferably 2 to 6 carbon atoms, and for instance 2, 3, 4, 5 or 6 carbon atoms. Examples of alkynyl groups are ethynyl, 2-propynyl, 2-butynyl, 3- butynyl, 2-pentynyl and its isomers, 2-hexynyl and its isomers, 9 2-heptynyl and its isomers, 2-octynyl and its isomers and the like. As used herein, the term C2-C20 alkynyl refers to an alkynyl of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 , 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms.

5 Where alkyl groups as defined are divalent, i.e., with two single bonds for attachment to two other groups, they are termed "alkylene" groups. Non-limiting examples of alkylene groups includes methylene, ethylene, methylmethylene, trimethylene, propylene, tetramethylene, ethylethylene, 1,2-dimethylethylene, pentamethylene and hexamethylene. Similarly, where alkenyl groups as defined above and alkynyl groups as 10 defined above, respectively, are divalent radicals having single bonds for attachment to two other groups, they are termed "alkenylene” and "alkynylene" respectively.

The term "aryl" as used herein by itself or as part of another group refers but is not limited to 5 to 24 carbon-atom homocyclic (i.e., hydrocarbon) monocyclic, bicyclic or 15 tricyclic aromatic rings or ring systems containing 1 to 4 rings which are fused together or linked covalently, typically containing 5 to 8 atoms; at least one of which is aromatic. The aromatic ring may optionally include one to three additional rings (either cycloalkyl, heterocyclyl or heteroaryl) fused thereto. Non-limiting examples of aryl comprise phenyl, biphenylyl, biphenylenyl, 5- or 6-tetralinyl, 1-, 2-, 3-, 4-, 5-, 6-, 7- or 20 8-azulenyl, 1- or 2- naphthyl, 1-, 2- or 3-indenyl, 1-, 2- or 9-anthryl, 1- 2-, 3-, 4- or 5-acenaphtylenyl, 3-, 4- or 5-acenaphtenyl, 1-, 2-, 3-, 4- or 10-phenanthryl, 1- or 2-pentalenyl, 1,2-, 3- or 4-fluorenyl, 4- or 5-indanyl, 5-, 6-, 7- or 8-tetrahydronaphthyl, 1 ,2,3,4-tetrahydronaphthyl, 1 ,4- dihydronaphthyl, dibenzo[a,d]cylcoheptenyl, 1-, 2-, 3-, 4- or 5-pyrenyl. As used herein, the term C5-C24 aryl refers to an aryl of 5, 6, 7, 8, 9, 10, 25 11 , 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,22, 23, or 24 carbon atoms. The term "heteroaryl" as used herein by itself or as part of another group refers but is not limited to 5 to 12 carbon-atom aromatic rings or ring systems containing 1 to 3 rings which are fused together or linked covalently, typically containing 5 to 8 atoms; at least one of which is aromatic in which one or more carbon atoms in one or more of these rings can 30 be replaced by oxygen, nitrogen or sulfur atoms where the nitrogen and sulfur heteroatoms may optionally be oxidized and the nitrogen heteroatoms may optionally bequatemized. Such rings may be fused to an aryl, cycloalkyl, heteroaryl or heterocyclyl ring.

10

The term "hydroxyalkyl" refers to a -Rb-OH group wherein Rb is alkylene as defined herein.

The term "amino" refers to the group -NH2.

5

The term "alkylamino" refers to the group -N(Re)(Rf) wherein Re and Rf are each independently selected from hydrogen and alkyl which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, alkylfuryl, furylalkyl, 10 hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

The term "aminoalkyl" refers to the group -Rb-NH2 wherein Rb is alkylene which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, 15 hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

The term "alkylaminoalkyl" refers to the group -Rb-NReRf wherein Rb is alkylene which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, 20 alkylfuryl, furylalkyl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio, Re is hydrogen or alkyl which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, alkylfuryl, furylalkyl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio, and Rf is hydrogen or alkyl which 25 is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

30 The term "carboxy" is equivalent to "hydroxycarbonyl" and refers to the group - CO2H. The term "alkylcarboxy" is equivalent to "alkyloxycarbonyl" and refers to the group -CC>2-Ra, wherein Ra is alkyl which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, hydroxyalkylfurylalkyl, isocyanate, 11 formyl, halocarbonyl, thiol, and alkylthio. The term "alkenylcarboxy" is equivalent to "alkenyloxycarbonyl" and refers to the group -C02-Rc, wherein Rc is alkenyl which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, 5 hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

The term carboxaldehyde or formyl refers to the group C(=0)H.

The term "furyl" refers to the group represented by formula III: 10

formula III

Asterisks (*) are used herein to indicate the point at which a mono-, bi- or trivalent radical depicted is connected to the structure to which it relates and of which the radical 15 forms part. The term "furylalkyl" refers to the group -Rb-fiiryl, wherein furyl is as defined above and Rb is alkylene which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio. The term "hydroxyalkylfurylalkyl" refers to 20 the group -R -furyl-R -OH, wherein furyl is as defined above and R is alkylene as defined above.

The term "alkylfuryl" refers to the group -furyl-Rb, wherein furyl is as defined above and Rb is alkylene which is optionally substituted with one or more substituents selected 25 from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

The term "alkoxy" or "alkyloxy" refers to the group -0-Ra wherein Ra is alkyl which is 30 optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

12

The term "alkoxyalkyl" or "alkyloxyalkyl" refers to the group -Rb-0-Ra wherein Ra is alkyl which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, 5 alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio and R alkyl which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio. The term "alkenyloxy" refers to the group -0-Rb wherein Rb is alkenyl 10 which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio. An example is vinyl ether.

15 The term alkyloxycarbonylalkenyl refers to the group -Rd-C(=0)-0-Ra, wherein Rd is alkenylene which is optionally substituted with one or more substituents selected from Q-C20 alkyl, C2-C 20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio, and Ra is alkyl which is optionally substituted with one or more 20 substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

The term "oxiranyl" refers to the epoxy group -C2H3O.

25

The term "alkylcarbonyl" refers to the group-C(=0)Ra, wherein Ra is alkyl which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and 30 alkylthio. Said alkylcarbonyl can be exemplified by acetyl, propionyl, butyryl, valeryl and pivaloyl.

The term "alkenylcarbonyl" refers to the group -C(=0)Rc wherein Rc is alkenyl as which is optionally substituted with one or more substituents selected from C1-C20 alkyl, 13 C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio. An example hereof is vinyl ketone.

5 The term "alkylcarbonyloxyalkyl" refers to the group -Rb-0-C(=0)Ra wherein Rb is alkylene which is optionally substituted with one or more substituents selected from d-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio, and Ra is alkyl which is optionally substituted with one or more 10 substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

The term "alkenylcarbonyloxyalkyl" refers to the group -Rb-0-C(=0)Rc wherein Rb is 15 alkylene which is optionally substituted with one or more substituents selected from Cj-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio. above and Rc is alkenyl which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 20 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

The term "alkylcarbonylalkenyl" refers to the -Rd-C(=0)-Ra group wherein Rd is alkenylene which is optionally substituted with one or more substituents selected from 25 Ci-C 20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio, and Ra is alkyl which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, 30 isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

The term "isocyanate" refers to the group -N=C=0. The term isocyanate-alkyl refers to the group -Ra-isocyanate, wherein Ra is alkylene which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5- 14 C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfiirylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

The term "nitro" refers to the group -NO2.

5

The term "cyano" refers to the group -CN.

The term "imino" refers to the group -C(=NH)R8 wherein Rg is alkyl, alkenyl or aryl which are each optionally substituted with one or more substituents selected from Ci-10 C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfiirylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

The term "thiol" or ""sulfhydryl" refers to the group -SH.

15

The term "alkylthio" refers to the group -SRa group wherein Ra is alkyl which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, hydroxyalkylfiirylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio. This term 20 refers to a group consisting of a sulfur atom attached to an alkyl group. Non-limiting examples of alkylthio groups include methylthio (SCH3), ethylthio (SCH2CH3), n-propylthio, isopropylthio, n-butylthio, isobutylthio, sec-butylthio, tert-butylthio, n-hexylthio, and the like.

25 The term "thioalkyl" refers to the group -R -SH wherein R is alkylene which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfiirylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio. Non- limiting examples of thioalkyl groups include thiomethyl, thioethyl, 30 thiopropyl, thiobutyl, thiopentyl, thiohexyl, thioheptyl, thiooctyl, thiooctadecyl, and the like. The term alkylthioalkyl" refers to the group -Rb-S-Ra wherein Rb is alkylene which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C2o alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfiirylalkyl, isocyanate, formyl, halocarbonyl, thiol, 15 and alkylthio and Ra is alkyl which is optionally substituted with one or more substituents selected from d- C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

5

The term "sulfonic acid" refers to the group -S(=0)20H.

The term "alkylsulfonyl" refers to the group -S(=0)2Ra wherein Ra is alkyl as which is optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 10 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio.

The term "halo" or "halogen" as a group or part of a group is generic for fluoro, chloro, 15 bromo or iodo. The term "haloalkyl" refers to an alkyl radical having the meaning as defined above wherein one or more hydrogen atoms are replaced with a halogen as defined above. Non-limiting examples of such haloalkyl radicals include chloromethyl, 1-bromoethyl, fluoromethyl, difluoromethyl, trifluoromethyl, 1,1,1 -trifluoroethyl and the like.

20

The term "haloalkenyl" refers to an alkenyl radical having the meaning as defined above wherein one or more hydrogen atoms are replaced with a halogen as defined above.

The term "halocarbonyl" refers to the group -C(=0)-Hal wherein Hal refers to a halogen 25 as defined above. Non-limiting examples of such halocarbonyl radicals include chlorocarbonyl (-C(=0)C1), bromocarbonyl (-C(=0)Br) or fluorocarbon (-C(=0)F). The term "haloaryl" refers to an aryl radical having the meaning as defined above wherein one or more hydrogen atoms are replaced with a halogen as defined above.

30 Whenever the term "substituted" is used in the present invention, it is meant to indicate that one or more hydrogen atoms on the atom indicated in the expression using "substituted" is replaced with a selection from the indicated group, provided that the indicated atom's normal valency is not exceeded, and that the substitution results in a 16 chemically stable compound, i.e. a compound that is sufficiently robust to survive isolation to a useful degree of purity from a reaction mixture.

Whenever used in the present invention the term "compounds of the invention" or a 5 similar term is meant to include the compounds of formula I, formula II, formula II', and formula IV and V (see below) as defined herein.

The terms "composition", "impregnation composition", "impregnating solution" and "furan resin" are used herein as synonyms, and all refer to a composition comprising 10 substituted furan compounds as defined herein.

In another preferred embodiment, the invention relates to the use of a composition as defined above, comprising furan compounds of formula I and/or formula II wherein n is an integer between 0 and 5, and preferably is 0, 1 , 2, 3, 4, or 5 wherein t and s each 15 independently are an integer between 1 and 5, and preferably each are 1 or 2, wherein w and z each independently are 0 or 1 , wherein X and Y each independently are O, S or N-R1 2 3 4 5 6 7 8 9 10 11 and wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15' R16, R18, R19, R2 are each independently hydrogen or selected from the group comprising C1-C20 2 alkyl, carboxaldehyde, hydroxyalkyl, carboxyl, amino, nitro, alkylamino, aminoalkyl, 3 alkoxyalkyl, alkylaminoalkyl, alkylcarboxy, alkenylcarboxy, furyl, fiirylalkyl, 4 hydroxyalkylfurylalkyl, alkyloxy, alkenyloxy, alkylcarbonylalkenyl, oxiranyl, 5 alkenylcarbonyl, alkylcarbonyloxyalkyl, alkyloxycarbonylalkenyl, 6 alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, alkylcarbonyl, halocarbonyl, 7 haloalkyl, haloaryl, haloalkenyl, imino, thioalkyl, alkylthioalkyl, cyano and any 8 mixtures thereof, and preferably from the group comprising, C1-C20 alkyl, 9 carboxaldehyde, hydroxyalkyl, carboxyl, alkylamino, aminoalkyl, alkylaminoalkyl, 10 alkyloxy, alkoxyalkyl, fiirylalkyl, hydroxyalkylfurylalkyl, alkenyloxy, 11 alkylcarbonylalkenyl, alkenylcarbonyl, alkylcarbonyloxyalkyl, alkyloxycarbonylalkenyl, alkenylcarbonyloxyalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyl, and any mixtures thereof, and even more preferred from the group comprising C1-C10 alkyl, carboxaldehyde, hydroxyalkyl, alkylamino, aminoalkyl, alkylaminoalkyl, alkyloxy, alkoxyalkyl, fiirylalkyl, hydroxyalkylfurylalkyl, carboxyl, 17 alkenyloxy, alkylcarboxy, alkenylcarboxy, alkylcarbonyl, alkenylcarbonyl, and any mixtures thereof, and still more preferred from the group comprising C1-C10 alkyl, carboxaldehyde, hydroxyalkyl, aminoalkyl, alkylaminoalkyl, alkoxyalkyl, furylalkyl, hydroxyalkylfurylalkyl, carboxyl, and any mixtures thereof, whereby each group is 5 optionally substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio, and wherein R17 and R20 are each independently selected from the group comprising C1-C20 alkyl, carboxaldehyde, hydroxyalkyl, carboxyl, amino, nitro, 10 alkylamino, aminoalkyl, alkoxyalkyl, alkylaminoalkyl, alkylcarboxy, alkenylcarboxy, furyl, furylalkyl, hydroxyalkylfurylalkyl, alkyloxy, alkenyloxy, alkylcarbonylalkenyl, oxiranyl, alkenylcarbonyl, alkylcarbonyloxyalkyl, alkyloxycarbonylalkenyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, alkylcarbonyl, and any mixtures thereof, and preferably from the group comprising C1-C20 alkyl, carboxaldehyde, 15 hydroxyalkyl, carboxyl, alkylamino, aminoalkyl, alkylaminoalkyl, alkyloxy, alkoxyalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkenyloxy, alkylcarbonylalkenyl, alkenylcarbonyl, alkylcarbonyloxyalkyl, alkyloxycarbonylalkenyl, alkenylcarbonyloxyalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyl, and any mixtures thereof, and even more preferred from the group comprising C1-C10 alkyl, 20 carboxaldehyde, hydroxyalkyl, alkylamino, aminoalkyl, alkylaminoalkyl, carboxyl, alkyloxy, alkoxyalkyl, furylalkyl, hydroxyalkylfurylalkyl alkenyloxy, alkylcarboxy, alkenylcarboxy, alkylcarbonyl, alkenylcarbonyl, and any mixtures thereof, and still more preferred from the group comprising C1-C10 alkyl, carboxaldehyde, hydroxyalkyl, aminoalkyl, carboxyl, and any mixtures thereof, whereby each group is optionally 25 substituted with one or more substituents selected from C1-C20 alkyl, C2-C20 alkenyl, C2-C20 alkynyl, C5-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio, and wherein the dotted line represents a double bond.

30 In another preferred embodiment the invention relates to the use of a composition comprising a compound of formula I and/or formula II, wherein n is 0, 1 , 2, 3, 4 or 5 wherein t and s each independently are 1 or 2, wherein w and z each independently are 0 or 1 , wherein X and Y each independently are O, S or N-R21 and wherein R2, R3, R4, R5, R6, R7, R9, R10, R11, R12, R13, R14, R15, R16, R18, R19, R21 are each independently 18 hydrogen or selected from the group comprising C1-C2 alkyl, carboxaldehyde, hydroxyalkyl, carboxyl, aminoalkyl, alkylaminoalkyl hydroxyalkylfurylalkyl, alkyloxy, alkoxyalkyl, alkylcarbonylalkenyl, alkylcarbonyloxyalkyl, alkyloxycarbonylalkenyl, alkenylcarbonyloxyalkyl, oxiranyl, isocyanate, isocyanate-alkyl, alkylcarboxy, 5 alkenylcarboxy, alkylcarbonyl, alkenylcarbonyl, halocarbonyl, haloalkyl, haloaryl, haloalkenyl, imino, thioalkyl, alkylthioalkyl, cyano and any mixtures thereof, whereby each group is optionally substituted with one or more substituents selected from C1-C2 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, hydroxyl, carboxyl, nitro, amino, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, and thiol, wherein R1, R8, R17 10 andR20 are each independently selected from the group comprising C1-C2 alkyl, carboxaldehyde, hydroxyalkyl, carboxyl, aminoalkyl, alkylaminoalkyl, hydroxyalkylfurylalkyl, alkyloxy, alkoxyalkyl, alkylcarbonylalkenyl, alkylcarbonyloxyalkyl, alkyloxycarbonylalkenyl, alkenylcarbonyloxyalkyl, oxiranyl, isocyanate, isocyanate-alkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyl, 15 alkenylcarbonyl, halocarbonyl, haloalkyl, haloaryl, haloalkenyl, imino, thioalkyl, alkylthio alkyl, cyano and any mixtures thereof, whereby each group is optionally substituted with one or more substituents selected from C1-C2 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, hydroxyl, carboxyl, nitro, amino, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, and thiol, and wherein the dotted line represents a 20 double bond.

In another preferred embodiment the invention relates to the use of a composition comprising a compound of formula I and/or formula II wherein n is an integer between 0 and 5 wherein t and s each independently are 1 or 2, wherein w and z each 25 independently are 0 or 1 , wherein X and Y are each independently O, S or N-R21 and wherein R2, R3, R4, R5, R6, R7, R9, R10, R11, R12, R13, R14, R15, R16, R18, R19, R21 are each independently hydrogen or selected from the group comprising C1-C2 alkyl, carboxaldehyde, hydroxyalkyl, carboxyl, aminoalkyl, alkylaminoalkyl hydroxyalkylfurylalkyl, alkoxyalkyl, oxiranyl and isocyanate, wherein R1, R8, R17 and 30 R20 are each independently selected from the group comprising C1-C2 alkyl, carboxaldehyde, hydroxyalkyl, carboxyl, aminoalkyl, alkylaminoalkyl, hydroxyalkylfurylalkyl, alkoxyalkyl, oxiranyl and isocyanate, and wherein the dotted line represents a double bond.

19

In another preferred embodiment of the invention the a composition is used comprising a compound of formula I and/or formula II, wherein n is 0, 1 , 2, 3, 4, or 5, wherein t is 1 or 2, wherein s is 1 or 2, wherein w is 0 or 1 , wherein z is 0 or 1 , wherein X is O, S or N-R21 , and wherein Y is O, S or N-R21; wherein R1 is hydrogen or selected from the 5 group comprising Ci-Cg alkyl, C2-Cg alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -NO2, -C2H3O, - CH2NH2, -N=C=0, -ch3-10 N=C=0, -0-CH=CH2, -C(=0)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0- C(=0)-CH=CH2, wherein R2 is hydrogen or selected from the group comprising Ci-Cg alkyl, C2-C8 alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even 15 more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -N02, -C2H30, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, -C(=O)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R3 is hydrogen or selected from the group comprising Ci-C8 alkyl, C2-C8 alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, 20 furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, -C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, - C(=0)H, -no2, -c2h3o, - ch2nh2, -n=c=o, -ch3-n=c=o, -o-ch=ch2, - C(=O)0CH3, -C(=0)0C2Hs, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein 25 R4 is hydrogen or selected from the group comprising Ci-C8 alkyl, C2-C8 alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, 30 -C(=0)H, -N02, -C2H30, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, - C(=O)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R5 is hydrogen or selected from the group comprising Ci-C8 alkyl, C2-C8 alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, 20 alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -no2, -c2h3o, - ch2nh2, -n=c=o, -ch3-n=c=o, -o-ch=ch2, - C(=O)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein 5 R6 is hydrogen or selected from the group comprising Ci-Cg alkyl, C2-Cg alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, 10 -C(=0)H, -N02, -C2H30, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, - C(=O)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R7 is hydrogen or selected from the group comprising Ci-Cg alkyl, C2-C8 alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, 15 alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -no2, -c2h3o, - ch2nh2, -n=c=o, -ch3-n=c=o, -o-ch=ch2, - C(=O)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R8 is hydrogen or selected from the group comprising Ci-Cg alkyl, C2-Cg alkenyl, 20 carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -no2, -c2h3o, - ch2nh2, -n=c=o, -ch3-n=c=o, -o-ch=ch2, - 25 C(=0)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R9 is hydrogen or selected from the group comprising Ci-Cg alkyl, C2-Cg alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanatealkyl, and even 30 more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -no2, -c2h3o, - ch2nh2, -n=c=o, -ch3-n=c=o, -o-ch=ch2, - C(=O)0CH3, -C(=0)0C2H5, -CH2 -fury I- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R10 is hydrogen or selected from the group comprising Ci-Cg alkyl, C2-Cg alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, 21 fiirylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -NO2, -C2H3O, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, -5 C(=O)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R11 is hydrogen or selected from the group comprising Cj-Cg alkyl, C2-C8 alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even 10 more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -NO2, -C2H3O, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, -C(=O)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R12 is hydrogen or selected from the group comprising Ci-Cg alkyl, C2-C8 alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, 15 furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -NO2, -C2H3O, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, -C(=O)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein 20 R13 is hydrogen or selected from the group comprising Ci-Cs alkyl, C2-Cg alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, 25 -C(=0)H, -NO2, -C2H3O, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, - C(=O)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R14 is hydrogen or selected from the group comprising Ci-Cs alkyl, C2-Cs alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, 30 alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -N02, -C2H3O, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, -C(=O)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R15 is hydrogen or selected from the group comprising Ci-Cs alkyl, C2-Cg alkenyl, 22 carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, 5 -C(=0)H, -N02, -C2H30, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, - C(=O)0CH3, -C(=0)0C2H5, -CH2-fiiryl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R16 is hydrogen or selected from the group comprising Ci-C8 alkyl, C2-C8 alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, 10 alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -no2, -c2h3o, - ch2nh2, -n=c=o, -ch3-n=c=o, -o-ch=ch2, - C(=O)0CH3, -C(=0)0C2H5, -CH2-fiiryl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R17 is selected from the group comprising Ci-Cg alkyl, C2-C8 alkenyl, carboxaldehyde, 15 hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -no2, -C2H30, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, -C(=O)0CH3, -C(=0)0C2H5, 20 -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R18 is hydrogen or selected from the group comprising Ci-C8 alkyl, C2-C8 alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -25 CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -N02, -C2H30, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, -C(=0)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R19 is hydrogen or selected from the group comprising Ci-C8 alkyl, C2-C8 alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, 30 alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -N02, -C2H30, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, -C(=O)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R20 is selected from the group comprising Ci-C8 alkyl, C2-C8 23 alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, 5 -C(=0)H, -NO2, -C2H3O, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, - C(=O)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, wherein R21 is hydrogen or selected from the group comprising Ci-Cg alkyl, C2-C8 alkenyl, carboxaldehyde, hydroxyalkyl, carboxyl, formyl, aminoalkyl, alkylaminoalkyl, furylalkyl, hydroxyalkylfurylalkyl, alkylcarboxy, alkenylcarboxy, 10 alkylcarbonyloxyalkyl, alkenylcarbonyloxyalkyl, isocyanate, isocyanate-alkyl, and even more preferred is -CH3, - C2H5, -C3H7, -C4H9, -CH2=CH, -CH2OH, -CH2NH2, -COOH, -C(=0)H, -NO2, -C2H3O, - CH2NH2, -N=C=0, -CH3-N=C=0, -0-CH=CH2, -C(=O)0CH3, -C(=0)0C2H5, -CH2-furyl- CH2OH or -CH2-0-C(=0)-CH=CH2, whereby each R group is optionally substituted with one or more substituents selected from Ci-15 C2o alkyl, C2-C2o alkenyl, C2-C2o alkynyl, Cs-C24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio, and preferably by one or more substituents selected from Ci-C2 alkyl, C2-C4 alkenyl, C2-C4 alkynyl, hydroxyl, carboxyl, nitro, amino, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, and thiol, and wherein the 20 dotted line represents a double bond.

In another preferred embodiment, non-limiting examples of furan compounds comprised in a composition used in the method according to the invention include but are not limited to 2,5- bis(hydroxymethyl)furan; 2,3,5-tris(hydroxymethyl)furan; 5-25 methyl-2-furfuryl alcohol, 3- hydroxymethyl-5-methyl-2-furfurylalcohol; 2,2'- (hydroxymethyl)difurylmethane; 2, 2’, 3,3'- (hydroxymethyl)difurylmethane; 2,2',4,4'-(hydroxymethyl)difurylmethane; 5- hydroxymethyl-[alpha]-(methyl)furfuryl alcohol; 5-hydroxymethyl-2-furancarboxaldehyde; 3,5- hydroxymcthyl-2-furancarboxaldehyde; 4,5-hydroxymethyl-2-furancarboxaldehyde; 5- methyl-2-furancarboxaldehyde; 3-30 hydroxymethyl-5-methyl-2-furancarboxaldehyde; 5-nitro furfuraldehyde; 2,5-bis(carboxaldehyde)furan; 3-hydroxymethyl-2,5- bis(carboxaldehyde)furan; 4-hydroxymethyl-2,5-bis(carboxaldehyde)furan; 5- hydroxymethyl-2-furoic acid; 5-methyl-2-furoic acid; 5-carboxaldehyde-2-furoic acid; 2,5- furandicarboxylic acid; 2,5-furan diacid dichloride; 2,5-furan dicarboxylic acid dimethyl ester; 5-hydroxymethyl-2- 24 furfurylamine; 5-methyl-2-furfurylamine; 5-carboxaldehyde-2- furfurylamine; 5-carboxy-2-furfurylamine; 2,5-bis(aminomethyl)furan; 5-methyl-2- vinylfuroate; 5-tertbutyl-2-vinyl furoate; 5-methyl-2-vinyl furan; 5-methyl-2-furfurylidene acetone; 5-methyl-2-furyloxirane; 5-methyl-fur fury 1 vinyl ether; 5-hydroxymethyl-2-ethyl 5 furanacrylate; bis-(2,5-isocyanatemethyl) furan; and bis(2,5-isocyanate) furan; or any mixtures thereof.

In an embodiment, the impregnating composition used in the method according to the invention comprises 2,5-bis(hydroxymethyl)furan (BHMF). In another embodiment the 10 impregnating composition used in the method according to the invention comprises 2,3,5-tris(hydroxymethyl)furan (THMF). In yet another embodiment the impregnating composition used in the method according to the invention comprises 2,2'-hydroxymethyldifurylmethane (HMDM). In still another embodiment the impregnating composition used in the method according to the invention comprises 5-hydroxymethyl-15 2- furfurylamine. In still another embodiment the impregnating composition used in the method according to the invention comprises 5-hydroxymethyl-2-furancarboxaldehyde. In still another embodiment the impregnating composition used in the method according to the invention comprises 5-methyl-2-furfuryl alcohol. In still another embodiment the impregnating composition used in the method according to the invention comprises 5-20 hydroxymethyl-[alpha]-(methyl)furfuryl alcohol. In yet another embodiment the impregnating composition used in the method according to the invention comprises 2, 2’, 3,3’- (hydroxymethyl)difurylmethane. In another embodiment the impregnating composition used in the method according to the invention comprises 2,2',4,4'-(hydroxymethyl)difurylmethane. In a further embodiment, the invention relates to the 25 use of a composition comprising 2,5-bis(hydroxymethyl)furan (BHMF), 2,3,5- tris(hydroxymethyl)furan (THMF), and 2,2’-hydroxymethyldifurylmethane (HMDM).

In another further embodiment, the invention relates to the use of a composition comprising 2,5-bis(hydroxymethyl)furan (BHMF); 2,3,5-tris(hydroxymethyl)furan 30 (THMF); and 2,2'-(hydroxymethyl)difurylmethane (HMDM); and optionally condensation products of BHMF, THMF and/or HMDM, and/or mixtures thereof.

The term "condensation product" as used herein refers to a compound with structural formula IV

25 'V?3 R4 R5 . R6 ƒ i „O- ^X/—R6 o •-"• —

W | Z

L JI s— -* s

Jn

formula IV

5 wherein n is preferably between O and 5, and more preferably 1 , 2, 3 or 4; wherein t is 1 or 2; wherein s is 1 or 2; wherein w is 0 or 1 ; wherein z is 0 or 1 , wherein R2, R3, R4, R5, R6, R7 are each independently hydrogen, methyl, a hydroxyalkyl or a hydroxyalkylfurylalkyl, wherein R1, R8 are each independently selected from the group comprising methyl, hydroxyalkyl, and hydroxyalkylfurylalkyl. In a more preferred 10 embodiment R2, R3, R4, R5, R6, and R7 are each independently -H, -CH3, -CH2OH or -CH2-furyl-CH20H (=hydroxymethylfurylmethyl), and R1 and R8 are each independently -CH3, -CH2OH or - CH2-fhryl-CH2OH.

In another preferred embodiment the invention relates to a polymerisable composition 15 for impregnating and modifying wood comprising a compound of formula I and/or formula II wherein n, t, s, w, z, X, Y, R2, R3, R4, R5, R6, R7, R9, R10, R11, R12, R13, R14, R15, R16, R17 R18, R19, R20 R21 are as defined above, and wherein the dotted line represents a double bond, provided that R17 and R20 are not a Ci-C2o alkyl, and preferably not methyl, and/or provided that the compound is not 2,5 dimethylfuran, 2,4 20 dimethylfuran, 2-acetyl-5- methylfuran, 2,5 dimethyl-3-acetylfuran, 2,3,5- trimethylfuran, 2-viny 1-3-methylfuran, 2-methyl benzo furan, dimethylbenzofuran, dibenzo furan, 2,3-dimethyl-5-ethylfuran, 3,4- dimethyl-5-ethylfuran, 2-ethyl-2,3-dihydro-5-methylfuran, 2,5-tetrahydrodimethylfiiran, 2- methyltetrahydrofuran-3-one, 2,5-dimethyltetrahydrofuran-3-one, 2-acetyltetrahydrofuran- 3-one, 4-methyl-2-furoic 25 acid, 2-(5-methylfuryl)-methyl ketone, 4-methyl furfural, 5-methyl furfural, 2-methyl-3-furfural, 3-methyl-2-furfural, 5-hydroxymethyl-2-furfiiral, bis furfuryl-2- furan, or 2,5-difurfuryledine-1 -cyclopentanone.

26

Furan compounds can be applied in varying amounts in the present composition depending on the wood density and the solid content of the composition comprising substituted furan compounds. It can be adapted according to the desired properties of 5 wood one wants to obtain such as increased density, increased hardness, increased durability, increased fire resistance (FRE or Fire Retardant Efficiency), increased dimensional stability, a desired modulus of elasticity (MOE), improved Anti swelling efficiency (ASE), reduced equilibrium moisture content (EMC), etc... In a preferred embodiment, the amount of substituted furan compounds in the present composition 10 varies between 3 and 100 % by weight and preferably between 10 and 60% by weight.

In another preferred embodiment, the amount of substituted furan compounds being impregnated in the wood varies between 3 and 100 % by weight on wood and preferably between 10 and 60% by weight on wood.

15

Substituted furan compounds in a composition used in the method according to the invention are used in an amount such that the weight percentage gain (WPG) of the wood after impregnation and reaction with the wood is at least 3% and for instance can vary from 3% to 150%, more preferably from 5% to 100% and even more preferable 20 between 10% and 60%, and more preferably between 20 and 40% by weight.

In another embodiment, the invention relates to a composition comprising more than 60 % by weight, and preferably more than 70% by weight of a compound of formula I and/or formula II, wherein n is smaller than or equal to 5, and - 0 to 40% by weight, 25 preferably 0 to 30% by weight of condensation products thereof. Preferably, the invention relates to a composition comprising more than 70% by weight, preferably more than 80 % by weight, and more preferred more than 90% by weight of a compound of formula II, - 0 to 30% by weight, preferably 0 to 20% by weight, more preferred 0 to 10% by weight of a compound of formula I, wherein n is smaller than or 30 equal to 5, and preferably smaller than or equal to 2, and more preferably 0 or 1 , and optionally 0 to 40% by weight, preferably 0 to 30% by weight of condensation products thereof.

27

In a preferred embodiment, the invention provides a composition comprising a mixture of: up to 70 % by weight, preferably up to 55 %, more preferably up to 25% by weight of2,5-bis(h y droxymethy 1) fur an (BHMF), up to 20 % by weight, preferably up to 15 %, more preferably up to 5% by weight of 2,3,5-tris(hydroxymethyl)furan (THMF), and up 5 to 10 % by weight, preferably up to 5 %, more preferably up to 1 % by weight of 2,2'-hydroxymethyldifurylmethane (HMDM).

Optionally the composition may further comprise up to 40 % by weight, preferably up to 30 % by weight of condensation products of BHMF, THMF and/or HMDM. In 10 another embodiment, the invention relates to a composition comprising: up to 60 % by weight, and preferably up to 30% by weight of a compound of formula I and/or formula II, wherein n is smaller than or equal to 5, and up to 40% by weight, preferably up to 60% by weight of condensation products thereof.

15 In the present invention the polymerisable impregnation composition preferably comprises disubstituted, trisubstitured or polysubstituted furan compounds or a mixture thereof and may contain a solvent, catalyst (initiator), coupling agent, filler, fire retardant, oil(wax) and/or surfactant. In accordance with the present invention the impregnation composition does not set nor react even over extended periods of time, 20 such that it has a long shelf-life. In addition, substituted furan compounds as defined herein, or substituted furan compounds diluted in a solvent are stable in the presence of a catalyst at room temperature.

In a preferred embodiment of the present invention the compounds of the present 25 composition are diluted in a solvent. Preferably the concentration of the furan compounds in such dilution is between 5 and 95 wt%, and more preferably between 10 and 80 wt% Examples of suitable solvents which may be used in a composition used in the method according to the invention comprise but are not limited to water, alcohols such as ethanol or methanol, dioxane, N,N dimethylformamide, acetone, ethyleneglycol, 30 or glycerol. In a more preferred embodiment the solvent is water. The furan compounds according to the invention are preferably water soluble. In a more preferred embodiment the furan compounds according to the invention are water-soluble in presence of a catalyst. As used herein the term "water soluble" refers to the amount that is soluble, after standing at least 48 hours in water at room temperature, when 5.0 grams of furan 28 compounds is added to 95.0 grams deionized water. The percentage of water solubility can be calculated by the formula: % Water solubility = 100 x (5.0 grams furan compounds - weight of water insoluble residue) / (5.0 grams furan compounds).

5 In the present invention, the present furan compounds can react with wood in the presence or the absence of a catalyst. The composition used in the method according to the invention may thus further comprise a catalyst. The catalysts may be a metallic salt, an ammonium salt, an organic acid, an anhydride, an inorganic acid or any mixtures thereof. In an embodiment the catalysts are metallic salts such as metalhalogenides, 10 metalsulfates, metalnitrates, metalphosphates or their mixtures. Examples are magnesium chloride, magnesium sulfate, magnesium nitrate, zinc chloride, zinc nitrate, aluminum chloride, aluminum nitrate, aluminum sulfate or their mixtures. In another embodiment the catalyst is an ammonium salt. Examples are ammonium chloride, ammonium sulfate, ammonium phosphate, ammonium carbonate, ammonium 15 bicarbonate, ammonium oxalate, ammonium citrate, ammonium nitrate, ammonium fumarate, ammonium levulinate or their mixtures. Other catalysts may be organic acids or inorganic acids. Suitable examples hereof are formic acid, acetic acid, propionic acid, butyric acid, pentanoic acid, hexanoic acid, oxalic acid, maleic acid, maleic anhydride, adipic acid, citric acid, furoic acid, benzoic acid, phtalic anhydride, paratoluene 20 sulphonic acid, hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, boric acid, silicic acid, benzoylperoxide or their mixtures. Depending on the type of catalyst and of the curing temperature and desired wood properties, the composition may comprise up to 20 % (or more), generally in the range of 1-15 %, preferably 8-10 %, more preferably 5-8 %, yet more preferably 5 % by weight on catalyst on the amount of substituted furan 25 compounds in the composition. Catalyst amount is hereby calculated on the amount of "dry" furan compounds. In another preferred embodiment, several compounds according to the present invention, including but not limited to 2,5-bis(hydroxymethyl)furan (BHMF); 2,3,5- tris(hydroxymethyl)fiiran (THMF); 2,2'-(hydroxymethyl)difurylmethane; (HMDM); condensation products thereof, 2,2',3,3'-30 (hydroxymethyl)difurylmethane; 2, 2’, 4,4'- (hydroxymethyl)difurylmethane, are obtained by hydroxymethylation of furfuryl alcohol with a formaldehyde source. The term "formaldehyde source" as used herein refers to formaldehyde, paraformaldehyde, trioxane, or any hemiformal.

29

The invention also provides a wood product which obtainable in accordance with the method according to any of the foregoing claims. Such a wood product has a good durability combined with a mechanical strength which is a maximum of only 10-15% lower than the wood before the treatment.

5

The invention further provides a system suitable for performing the method according to the invention, comprising: an impregnation device for impregnating wood with a reactive composition, in particular a polymerisable composition, and a chemical modification device provided with heating means for allowing the impregnated wood to 10 react under the influence o f heat.

In an embodiment of the system according to the invention the impregnation device is adapted for forcing the reactive composition through the wood at least partially by using pressure. The impregnating device may be pressurized by using any suitable apparatus, 15 such as, for example, a high volume transfer or pressure pump or air pressure provided by a compressor system. An inlet may be provided at one end of the device with pressure being relieved from the other end which allows for a high volume flow over and through the wood in the device. The wood will generally be fully submerged in the, commonly waterborne, reactive preservative, in particular polymerisable preservative. 20 The separation of the wood and the excess waterborne preservative may be performed by removing the wood from the preservative.

In an embodiment the chemical modification device comprises a treatment space sealable in medium-tight manner, a vacuum pump connected to the treatment space, a 25 steam source connected to the treatment space, a heating device which is in thermal contact with the treatment space, and measuring and control equipment adapted to measure at least the temperature and pressure inside the treatment space and to control the vacuum pump, the steam source and the heat source. The method according to the invention can be performed in simple manner using such a device. The apparatus can 30 herein be programmed optimally for the treatment of determined types of wood. In a particular embodiment the treatment space is bounded by a double wall provided with thermally conducting oil. The temperature inside the treatment space can hereby be readily controlled and kept homogeneous. The thermal oil is situated between the two walls of the double wall.

30

The apparatus according to the invention is preferably programmed for performing a method according to the invention. The apparatus can be provided for this purpose with a computer with which the measuring and control equipment is read and the vacuum 5 pump, the steam source and the heat source and possible other components are controlled.

The invention will now be elucidated on the basis of the following non-limitative embodiment, wherein: 10 Figure 1 shows a schematic view of the method according to the invention,

Figure 2 shows an impregnation device for use in a system according to the invention, and

Figure 3 shows a chemical modification device for use in a system according to the invention.

15

Figure 1 shows a schematic view of the method according to the invention, wherein in a first step 1 wood to be modified is impregnated with a waterborne polymerisable composition by means of a known vacuum-pressure method, after which, in a second step 2, the wood is dried in either a natural or a forced manner until the moisture content 20 has been reduced to about 14% by weight. In a third step 3 at least a fraction of oxygen contained by a treatment vessel is removed from the treatment vessel, after which, in a fourth step 4, the impregnated wood is heated gradually in the treatment vessel to chemically modify the wood, wherein the composition is polymerised within the wood, and - dependent on the maximum temperature applied in the vessel - eventually to 25 thermally modify the wood. In a subsequent fifth step 5 the wood is cooled down in a controlled manner, dependent on the wood and the polymerised composition used. In a final step 6 the modified wood is removed from the treatment vessel and can be used e.g. as a constructive element.

30 Figure 2 shows an impregnation device 48 for use in a system according to the invention. Referring to this figure, waterborne preservative (modifying agent) contained in a storage tank 7 is heated to the required temperature, such as 30-98 degrees Celsius, and then agitated by means of the agitation pump 8, wherein a valve 9 is open. Heating may be achieved either by an in-tank heater or a heat pump in the agitation line.

31

Agitation of the storage tank 7 is continuous. A pressure cylinder 10 is loaded with wood to be modified (not shown) and the door 11 closed and sealed. An initial vacuum, such as, 0-98 kPa, is drawn by means of valves 12, 13, 14 and 15 closed and valve 16 open, wherein a vacuum pump 17 is switched on. A vacuum control valve 18 maintains 5 the required level of vacuum (underpressure). The vacuum is reached and held for a predetermined time. The pressure cylinder 10 is then flooded with the hot preservative and valves 15 and 16 are opened. The level of vacuum is maintained by vacuum control valve 1. Once the cylinder 10 is flooded, valves 12 and 15 are closed. The vacuum pump 17 is then turned off. Pressures up to 1400 kPa are applied using a high volume 10 pressure pump 19 with valve 15 open. The pressure control valve 13 maintains the required pressure. The presence of the high volume pump 19 means that there is constantly fresh hot solution passing though the pressure cylinder 10 treating and heating the wood. Pressure is released via the vacuum control valve 18 to ramp down the pressure to 0 kPa. Once the modification treatment has been completed, there are 15 two alternatives for draining the pressure cylinder 10 as follows: (a) closing valve 15, opening vales 13,14 and 16 and using the high volume pressure pump 17 pump the cylinder dry; or (b) using the vacuum pump 17 as an air compressor so that the liquid can be blown out of the pressure cylinder 10 via line using valve 16 and by-passing the pump.

20 The advantage of using alternative (b) is that the pressure cylinder 10 can be emptied at the same pressure as the wood was treated or at a higher pressure meaning that any kickback is alleviated until the preservative has been removed from the cylinder and the pressure achieved, and can then be segregated. The kickback can then be collected after final vacuum and cleaned up prior to returning clean preservative to the storage tank 7. 25 After draining the cylinder, all the valves are closed apart from valve 12 and a vacuum such as -80 to -98 kPa is drawn on the pressure cylinder 10. After a predetermined time, the vacuum is vented through valve 18 and any residual liquid is then cleaned and/or recycled. The door 11 is then opened and the treated fixed timber removed for storage under cover until it is dispatched. A short holding period may be required before the 30 wood leaves the treatment containment area. This impregnation process as such is also known as the Bethall process. Prior heating of the polymerisable preservative may be omitted. Suitable compositions of the preservative used in the impregnation device 48 are given in the preceding description.

32

Figure 3 shows a chemical modification device 20 for use in a system according to the invention, comprising a treatment space 21 adapted to receive impregnated wood, which wood may for example be impregnated with a polymerisable composition by using the device 48 as shown in figure 2. The treatment space 21 is confined by a thermally 5 isolated outer reactor wall 22, and a thermally conducting inner reactor wall 23 which is filled with a thermally conductive oil. The treatment space 21 connects to a water container 24 containing water 25 that is heated by heating means 26 in order to generate steam, which is led to the treatment chamber 21 through a steam channel 27. Alternatively, the water container 24 is incorporated within the treatment space 21. The 10 amount of water should be sufficient for achieving the desired steam pressure in the reactor chamber 21, taking into account the additional water consumed by hydrolysis reactions and the amount of water adsorbed by the wood. The container 24 is sufficiently large to store the initial amount of water plus the amount released by condensation reactions, dehydration reactions and drying. The treatment space 21 is 15 provided with a mechanical stirrer 28 used to homogenize the generated steam and volatile reaction products, leading to a homogenous exposure of the treated wood parts 29. The wood parts 29 are preferably spaced apart, preferably having mutual distances of 8-15 mm, allowing for an even more homogenous treatment. If wood parts 29 are packed closely together, inner parts in a pile of wood parts 29 are less exposed than 20 outer parts, leading to different treatment of the parts. Preferably, the treatment space 21 and the water container 24 form a closed system, in order to optimize the use of water. Preferably, the system is provided with a safety pressure valve. During the processing of the impregnated wood, the water container can be used as a cold spot, wherein the water container 24 has a temperature lower than the treatment space 21, in order to ensure that 25 water condenses in the water container and not in the treatment space 21 where it could possibly condense on the wood 29. For safety reasons, the treatment space 21 is provided with at least one standard safety pressure release valve, set at a pressure below the maximum pressure the reactor walls 22,23 can withstand. Under operating conditions according to the invention, the pressure typically ranges from vacuum to a 30 maximum of approximately 12 bar, hence the safety pressure release valve could for instance be set at 14 bar. The pressure inside the treatment space 21 can be monitored by a standard pressure meter 47 covering the operating range. During operation the impregnated wood will be polymerised in the steam filled treatment space 21 by heating the treatment space 21 to a temperature of at least 70 degrees Celsius, after which the 33 temperature in the treatment space is raised gradually with a temperature gradient of a maximum of 40 degrees Celsius per hour, preferably between 20-40 degrees Celsius per hour, to a maximum temperature of between 120 and 220 degrees Celsius; wherein the wood is heated at said maximum temperature during a reaction time of at least 10 5 minutes. In case the maximum temperature exceeds 140 degrees Celsius during operation, the wood will be modified both chemically and thermally.

The treatment space 21 also connects to a first pressurized cylinder 30 comprising carbon dioxide (CO2), which is connected through an first automated dispensing valve 10 31. Carbon dioxide may be used to lower the pH in the reactor as carbon dioxide acidifies steam. The device 20 also comprises a second pressurized cylinder 32 of ammonia (NH3) also connected to a second automated dispensing valve 33. Having the possibility to add predetermined amounts of acid or base may be used to maintain the pH at a predetermined value during the treatment according to the invention. The pH is 15 monitored by taking samples of the steam in the reactor space 21 by temporarily opening a sample valve 34, condensing the sampled steam in a condenser 35, and collecting the condensed steam 36 for pH measurement using regular electrochemical pH measurement equipment 37.

20 The treatment space 21 is also provided with a vacuum pump system 38 for evacuating the treatment space 21, in particular for removing oxygen gas. The vacuum system 38 optionally includes a pressure meter for monitoring pressure within the treatment space 21. Instead of the optional pressure meter, it is also possible to rely on temperature and pH measurements only. The device 20 is provided with heating means 45 for heating 25 the reactor chamber 21, and a temperature measurement units (40, 41, 42) for the inner reactor wall 23 (unit 40), the wood 29 (unit 41) and the water 25 of the steam generator 24 (unit 42). A central control unit 43 monitors the temperature of the wood 41, the temperature of the inner reactor wall 23, the temperature of the steam water 25, the pressure within the treatment space 21, and the pH within the treatment space. The 30 control unit 43 will then, following the preset program or manual control, adjust these parameters. For instance, pressure can be increased by turning up the heater 26 of the steam generator, leading to increased steam evaporation, or lowered by lowering the temperature, water evaporation and/or opening the vacuum valve 44 of the vacuum system 38. The vacuum valve 44 is a three-way valve, that can also be used to 34 depressurize the reaction vessel 21, or to let air or an inert gas such as nitrogen into the treatment space 21 in order to remove vacuum. The temperature in the treatment space 21 can be adjusted by the wall heater unit 45. pH can be lowered by adding carbon dioxide 30, or increased by adding ammonia 32.

5 In figure 3 the characters A-H represent the following parameters: A: pH set B: pH read C. Twaii set D: TWaii read 10 E: TWood read F: Twater set G. Twater read H: Twater control 15 It is conceivable that the impregnation device 48 as shown in figure 2 and the modification device 20 as shown in figure 3 are physically connected to each other and/or are mutually integrated at least partially.

It should be noted that the above-mentioned embodiments illustrate rather than limit the 20 invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. Use of the verb “comprise” and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article “a” or “an” preceding an element does not exclude the presence of a plurality of such elements. The mere fact that certain 25 measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Claims

Method for modifying wood, in particular making wood more sustainable, comprising the processing steps:

Method according to claim 1, wherein the relative humidity in the treatment room is kept substantially constant during step B).

3. Method according to claim 1 or 2, wherein the relative humidity during step B) is between 65% and 85%.

A method according to any one of the preceding claims, wherein a water supply container is arranged in the treatment space, wherein water is evaporated from the water supply container during step B). 25

A method according to any one of the preceding claims, wherein the wood is completely impregnated with the reactive substance, in particular the polymerizable substance.

A) impregnating wood to be modified with a reactive substance, in particular a polymerizable substance, and B) reacting the impregnated wood in a steam-treated treatment space by heating the treatment space to a temperature of at least 70 degrees Celsius, whereafter the temperature in the treatment room is gradually increased with a temperature gradient of at most 40 degrees Celsius per hour, preferably between 20-40 degrees Celsius per hour; up to a maximum temperature of between 120-220 degrees Celsius; wherein the wood is heated at the maximum temperature for a reaction time of at least 10 minutes. 15

The method of any one of claims 1-5, wherein the wood is partially impregnated with the polymerizable substance.

A method according to any one of the preceding claims, wherein the maximum temperature during step B) is 140 degrees Celsius.

The method of any one of claims 1-6, wherein the maximum temperature during step B) is 190 degrees Celsius.

A method according to any one of the preceding claims, wherein the method further comprises step C), comprising, prior to performing step B), at least partially drying the impregnated wood.

10. A method according to any one of the preceding claims, wherein the method further comprises step D), comprising, before performing step B), removing at least a substantial part of the air, in particular oxygen, from the treatment room .

11. A method according to any one of the preceding claims, wherein the moisture content in the wood during step B) is 6 and 20% by mass of the drywood mass.

A method according to any one of the preceding claims, wherein during step C) the steam has a degree of saturation of at most 95%.

A method according to any one of the preceding claims, wherein during step C the steam has a pressure of at least 4 bar.

14. A method according to any one of the preceding claims, wherein the polymerizable substance comprises a chemical compound of formula I and / or formula II R 1 or R 1 R 5 Re y R? R1 r- R1C R14 R12 J8 L Jw R z L Jt L Js J n Formula I p ^ 18 pj19 r '^^ R20 Formula II wherein n is an integer between 0 and 20, preferably between 0 and 10, and more preferably between 0 and 5, wherein t and s each independently form an integer between 1 and 20, preferably between 1 and 10, more preferably between 1 and 5, wherein w and z are each independently 0 or 1 wherein X and Y are each independently O, S, or N-R21, wherein R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R18, R19, R21 each independently forms hydrogen or is selected from the group consisting of C1 -C20 alkyl, C2 -C20 alkenyl, C2 -C20 alkynyl, C5 -C24 aryl, C5 -C12 heteroaryl, carboxaldehyde, hydroxyl, hydroxyalkyl, carboxyl, amino, nitro, formyl, alkylamino, aminoalkyl, alkylaminoalkyl, furyl, furylalkyl, hydroxyalkyl furylalkyl, alkyloxy, alkoxyalkyl, alkenyloxy, alkylcarbonylalkenyl, oxiranyl, alkylcarbonyloxyalkyl, alkyloxycarbonylalkenyl, alkenylcarbonyloxyalkyl, isoc yanate, isocyanate-alkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyl, alkenylcarbonyl, halocarbonyl, haloalkyl, haloaryl, haloalkenyl, imino, thiol, alkylthio, thioalkyl, alkylthioalkyl, cyano, alkylsulfonyl, sulfonic acid, and any mixture thereof, with any group optionally replaced by one or more substituents selected from C 1 -C 20 alkyl, C 2 -C 20 alkenyl, C 2 -C 20 alkynyl, C 5 -C 24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkylfurylalkyl, isocyanate, formyl, halocarbonyl, thiol, and alkylthio, wherein R17 and R20 are each independently selected from the group consisting of C1 -C20 alkyl, C2 -C20 alkenyl, C2 -C20 alkynyl, C5 -C24 aryl, C5 -C12 heteroaryl, carboxaldehyde, hydroxyl, hydroxyalkyl, carboxyl, amino, nitro, formyl, alkylamino, aminoalkyl, alkylaminoalkyl, furyl, furylalkyl, hydroxyalkyl furylalkyl, alkyloxy, alkoxyalkyl, alkenyloxy, alkylcarbonylalkenyl, oxiranyl, alkylcarbonyloxyalkyl, alkyloxycarbonylalkenyl, alkenylcarbo nyloxyalkyl, isocyanate, isocyanate-alkyl, alkylcarboxy, alkenylcarboxy, alkylcarbonyl, alkenylcarbonyl, halocarbonyl, haloalkyl, haloaryl, haloalkenyl, imino, thiol, alkylthio, thioalkyl, alkylthioalkyl, cyano, alkylsulfonyl, sulfonic acid, and any mixture thereof, wherein any mixture is, optionally replaced by one or more substituents selected from C 1 -C 20 alkyl, C 2 -C 20 alkenyl, C 2 -C 20 alkynyl, C 5 -C 24 aryl, hydroxyl, carboxyl, nitro, amino, furyl, furylalkyl, alkylfuryl, hydroxyalkyl furylalkyl, isocyanate, formyl, halocarbonyl , thiol, and alkylthio, and wherein the dashed line represents an optional double bond.

A method according to any one of the preceding claims, wherein during step 5 A) the wood is impregnated with a polymerizable substance selected from the group comprising 2,5-bis (hydroxymethyl) furane; 2,3,5-tris (hydroxymethyl) furan; 5-methyl-2-furfuryl alcohol, 3-hydroxymethyl-5-methyl-2-furfuryl alcohol; 2,2 '- (hydroxymethyl) difurylmethane; 2,2 ', 3,3' - (hydroxymethyl) difurylmethane; 2,2 ', 4,4' - (hydroxymethyl) difurylmethane; 5-hydroxymethyl-α (methyl) furfuryl alcohol; 5-10 hydroxymethyl-2-furan carboxaldehyde; 3,5-hydroxymethyl-2-furan carboxaldehyde; 4,5-hydroxymethyl-2-furan carboxaldehyde; 5-methyl-2-furan carboxaldehyde; 3-hydroxymethyl-5-methyl-2-furan carboxaldehyde; 5-nitro furfuraldehyde; 2,5-bis (carboxaldehyde) furan; 3-hydroxymethyl-2,5-bis (carboxaldehyde) furan; 4-hydroxymethyl-2,5-bis (carboxaldehyde) furan; 5-hydroxymethyl-2-furanoic acid; 5-15 methyl 2-furanoic acid; 5-carboxaldehyde-2-furanoic acid; 2,5-furanedicarboxylic acid; 2,5-furanedioic acid dichloride; 2,5-furan dicarboxylic acid dimethyl ester; 5-hydroxymethyl-2-furrylamine; 5-methyl-2-furfurylamine; 5-carboxaldehyde-2-fiuryfuryl amine; 5-carboxy-2-furfurylamine; 2,5-bis (aminomethyl) furan; 5-methyl-2-vinyl furate; 5-tert-butyl-2-vinyl furate; 5-methyl-2-vinyl furan; 5-methyl-2-furfurylidene acetone; 5-20 methyl-2-furyloxirane; 5-methyl-furfuryl vinyl ether; 5-hydroxymethyl-2-ethyl furan acrylate; bis (2,5-isocyanatemethyl) furan; and bis (2,5-isocyanate) furan; or any mixture thereof.

16. A method according to any one of the preceding claims, wherein during step A) the wood is impregnated with a polymerizable substance comprising a chemical compound selected from the group comprising 2,5-bis (hydroxymethyl) furan (BHMF); 2,3,5-tris (hydroxymethyl) furan (THMF); 2,2 '- (hydroxymethyl) difuryl methane; (HMDM); 2.2 ', 3.3' (hydroxymethyl) difury 1 methane; 2,2 ', 4,4' - (hydroxymethyl) difuryl methyl or any mixture thereof. 30

A method according to any one of the preceding claims, wherein during step A) the wood is impregnated with a polymerizable substance comprising a chemical compound selected from the group comprising 2,5-bis (hydroxymethyl) furan (BHMF); 2,3,5-tris (hydroxymethyl) furan (THMF); 2,2'- (hydroxymethyl-difurylmethane (HMDM); and optionally, condensation products thereof, or mixtures thereof.

18. A method according to claim 16 or 17, wherein the chemical compound is obtained by hydroxymethylation of at least one furfuryl alcohol compound with a formaldehyde source.

19. A method according to any one of the preceding claims, wherein the concentration of the chemical compound of formula I and / or formula II in the polymerizable substance is between 3 and 100 mass percent.

A method according to any one of the preceding claims, wherein the chemical compounds are incorporated in a solvent, in particular water.

A method according to any one of the preceding claims, wherein the reactive substance, in particular the polymerizable substance, also comprises a catalyst.

22. Modified wood product obtainable according to the method according to any one of the preceding claims.

23. System suitable for carrying out the method according to any of claims 1-21, comprising: - an impregnation device for impregnating wood with a reactive substance, in particular a polymerizable substance, and - a chemical modifier provided with heating means for allowing the impregnated wood to react by heating.

A system according to claim 23, wherein the chemical modifier 30 comprises: - a treatment room that can be closed in a fluid tight manner, - a vacuum pump connected to the treatment room, - a steam source connected to the treatment room, - a heating device which is in thermal contact with the treatment room, and - measuring and control equipment adapted to measure at least the temperature and pressure within the treatment room and to control the vacuum pump, the steam source and the heat source.

The system of claim 24, wherein the treatment space is delimited by a double wall provided with thermally conductive oil.

A system according to any one of claims 23-25, wherein the impregnating device is adapted to pressurize the reactive substance, in particular the polymerising substance, by the wood to be modified.

27. System as claimed in any of the claims 23-26, programmed to perform a method as claimed in any of the claims 1-20.