AU2020213343A1 - Anti-fungal potentiators - Google Patents

Abstract

Provided herein a wood preservative formulation comprising: a non aqueous carrier; one or more anti-fungal preservative compounds; and one or more tertiary amine compounds. It is found that the tertiary amine component potentiates the efficacy of the fungicidal component. On the basis of several laboratory decay tests, it has been shown that C 14 -C1 8 alkyldimethylamines potentiate anti-fungal activity of azoles in non-aqueous, solvent-based formulations without the addition of organic acids.

Description

ANTI-FUNGAL POTENTIATORS

Field of the Invention The present invention relates to non-aqueous formulations of enhanced efficacy, used to protect solid wood, engineered wood products and other cellulosic substrates from biodeterioration by various organisms including moulds, decay fungi and insects. The inventive formulations comprise a tertiary amine component, which potentiates the efficacy of the fungicide by comparison with the fungicide sans amine. Although the invention will be described hereinafter with reference to this application, it will be appreciated that it is not limited to this particular field of use.

Background of the Invention Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of the common general knowledge in the field. Wood is a staple construction formulation used throughout the world. However, it is prone to degradation from elements including the natural environment, weather events, insects, rot and fire. Accordingly, a range of chemical treatments has been developed to improve the durability and working lifetime of wooden structures. To treat and prevent infestations, timber is often impregnated with a preservative such as a fungicide or insecticide. The preservative is typically present in a carrier, with the mixture being applied to the surface of the timber, for example by dipping, spraying, brushing or pressure treatment, such that the carrier and preservative are absorbed in to the timber. As such, the treatment of timber with preservative compounds involves the introduction of stable chemicals into the cellular structure of the timber. This, in turn, protects the timber from hazards such as fungi, insects and other wood-destroying organisms. Preservative treatments may also include the introduction of chemicals that improve resistance to degradation by fire. The majority of timber used in building and construction is grown sustainably in plantations. It contains a high proportion of sapwood and has heartwood that is typically of low natural durability. Plantation-grown timbers are therefore generally highly susceptible to biodegradation by various organisms including moulds, decay fungi and insects unless treated with a suitable wood preservative. In general, wood preservatives can be classified according to the carrier used to apply the preservative to the wood product, with the most common preservative types being either water-borne or solvent-borne preservatives. Solvent-borne preservatives use non-aqueous solvents such as mineral (white) spirits, kerosene or light oil to achieve the required penetration of the active ingredients through the wood structure. In Australia, the treatment of timber is governed by the Australian standard "AS 1604-2012". Hazard Class H3 is defined as being for protection against "moderate fungal decay and termite hazard" with examples of end uses being decking, fascia, cladding, window reveals, and exterior structure timber. The timber is exposed to the weather or not fully protected. It is clear from the ground and the area is well drained and ventilated. H3 treatment is designed to prevent attack by insects, including termites, and decay. In building and construction, where many of the timbers are subjected to Hazard-class or use-class 3 (outdoor, above-ground) exposure, solvent-based preservatives based on mineral spirit or kerosene have a variety of advantages over water-based systems. This is particularly true in markets where the timber product must be dry (equilibrium moisture content < 18-20%) at the point of sale. Solvent-based preservatives do not "wet" the timber substrate, such that it does not need to be re-dried after treatment. Similarly, non-aqueous solvents do not cause the timber to swell or distort during treatment. Hazard Class H4 defines the requirements for "severe decay, borers and termites", fence posts, greenhouses, pergolas (in ground and landscaping timbers)". The timber to which H4 is applicable is in contact with the ground or is continually damp so there is a severe decay hazard. The treatment stops attack by insects, including termites, and severe decay. "Penetration" is defined under the H3/H4 Standards as: "All preservative treated wood shall show evidence of distribution of the preservative in the penetration zone in accordance with the following requirements: (a) If the species of timber used is of natural durability class 1 or 2, the preservative shall penetrate all the sapwood. Preservative penetration of the heartwood is not required; (b) If the species of timber used is of natural durability class 3 or 4, the preservative shall penetrate all of the sapwood and, in addition one of the following requirements shall apply; (b(i)) Where the lesser cross-sectional dimension is greater than 35 mm, the penetration shall be not less than 8 mm from any surface. Where the lesser cross-sectional dimension is equal or less than 35 mm, the penetration shall be not less than 5 mm from any surface; and (b(ii)) Unpenetrated heartwood shall be permitted, provided that it comprises less than 20% of the cross-section of the piece and does not extend more than halfway through the piece from one surface to the opposite surface and does not exceed half the dimension of the side in the cross-section on which it occurs". In general terms, the costs of water-based and solvent-based treatments are broadly comparable. Although non-aqueous solvents are more expensive than water, the energy, handling and time associated with drying wood treated with water-based preservatives generally offset any price differential. Solvent-based preservatives that utilise white spirits or kerosene carriers also leave the treated timber suitable for painting, providing sufficient airing is allowed to occur after treatment. Solvent-based preservatives also find application in heavy duty, industrial applications where the treated timber is used in ground contact (Hazard-class or use-class 4). For ground contact end uses, light oil carriers are preferred because they are less volatile than white spirit or kerosene. A variety of active ingredients have been used in solvent-based wood preservatives. These include pentachlorophenol, organochlorine insecticides, bis(tributyltin)oxide, metal naphthenates such as tributyltin naphthenate, copper naphthenate and zinc naphthenate, and creosote. Copper oxine is also used in solvent based preservatives. Synthetic pyrethroids such as cypermethrin or permethrin have replaced the use of organochlorine insecticides in formulations used for protecting timber against insect attack. Organic triazoles such as cyproconazole, propiconazole and tebuconazole have been used as fungicides in "metal-free" preservative systems, with an insecticide added to protect the treated article from attack by borers or termites. In the case of solvent-based preservatives used for the treatment of building and construction timbers, organic fungicides such as the triazole combination of propiconazole and tebuconazole, along with a synthetic pyrethroid insecticide such as permethrin, are commonly used, particularly in countries such as Australia, New Zealand and South

Africa. The treated timber retains its natural colour and, when applied using white spirit or kerosene, can be readily painted. Metal-based active ingredients such as copper naphthenate, while being more robust in certain situations, e.g., where the treated timber is exposed close to the ground, intensely colour the timber and make it less suitable to paint. Other metal-based active ingredients such as zinc naphthenate, while being colourless, is not as efficacious as copper. Organic active ingredients such as pentachlorophenol display broad spectrum activity, but are now prohibited in many countries on account of their health and safety issues and environmental persistence. For industrial end uses where appearance is not a significant issue, copper naphthenate finds some use in the United States, although it is acknowledged that it contains some gaps in its spectrum of activity against certain copper-tolerant brown rot decay fungi. It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative. It is an object of an especially preferred form of the present invention to provide for improved efficacy of active ingredients currently used in solvent-based preservative systems. Improved azole-containing formulations are of particular interest. Unless the context clearly requires otherwise, throughout the description and the claims, the words "comprise", "comprising", and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of "including, but not limited to". Although the invention will be described with reference to specific examples it will be appreciated by those skilled in the art that the invention may be embodied in many other forms. As used throughout the ensuing description and claims, the term "potentiator" refers to compounds having the ability which, when combined with an anti-fungal compound, improve its effectiveness in some way. The potentiators themselves typically exhibit little if any of the desired activity.

Summary of the Invention According to a first aspect of the present invention there is provided a wood preservative formulation comprising: a non-aqueous carrier; one or more preservative compounds; and one or more tertiary amine compounds as a potentiator of the one or more preservative compounds. In an embodiment, the formulation is substantially free of acid, such that the tertiary amine is not quaternised. In an embodiment, the one or more tertiary amine compounds are selected from the group consisting of monoalkylamines, dialkylamines and triaklylamines. In an embodiment, the one or more preservative compounds and the one or more tertiary amine compounds are present in synergistic amounts. In an embodiment, the tertiary amine comprises methyl or ethyl substituents and/or alkyl substituents which may be either linear or branched, with, on average, a minimum of 8 carbons. In an embodiment, the tertiary amine is an alkyldimethylamine of the general formula RN(Me) 2 , wherein R is a linear or branched carbon chain, with an average chain length between 8-22 carbons per molecule. Preferably, R is a linear or branched carbon chain, with an average chain length between 14-18 carbons per molecule. In an embodiment, the tertiary amine is a dialkylmethylamine of the general formula MeN(R) 2 , wherein R is a linear or branched carbon chain, with an average chain length between 8-22 carbons per molecule. Preferably, R is a linear or branched carbon chain, with an average chain length between 14-18 carbons per molecule. In an embodiment, the tertiary amine is a trialkylamine of the general formula NR3 , wherein R is a linear or branched carbon chain, with an average chain length between 8-22 carbons per molecule. Preferably, R is a linear or branched carbon chain, with an average chain length between 14-18 carbons per molecule. In an embodiment, the tertiary amine potentiator is a mixture of different alkyl chain lengths. In an embodiment, the tertiary amine is N-(3-aminopropyl)-N dodecylpropane-1,3-diamine (Lonzabac@ 12). In an embodiment, the tertiary amine is selected from the Barlene@ group, Fentamine@ group, or Ablemarle@ group of alkyldimethylamines. In an embodiment, the alkyldimethylamines are selected from the group consisting of: Barlene@ 8S (N-octyl-N,N-dimethylamine); Barlene@ 10S (N-decyl-

N,N-dimethylamine); Barlene@ 12 (dodecyldimethylamine); Barlene@ 12C (dodecyldimethylamine); Barlene@ 12S (dodecyldimethylamine); Barlene@ 1214 (mixture, 62-68% C12,38% (max) C14,2% (max) C16,3% (max), others); Barlene@ 14S (N-tetradecyl-N,N-dimethylamine); Barlene@ 16S (N-hexadecyl-N,N dimethylamine); Barlene@ 1822 (alkydimethylamine, C20-22 N,N dimethyloctadecylamine (dimantine), C18); Barlene@ 18S (N,N dimethyloctadecylamine (dimantine), C18), and mixtures thereof. In an embodiment, the amines are selected from the group consisting of the Fentamine@ group of monoalkyl tertiary amines: Fentamine@ DMA897 (octyl dimethylamine); Fentamine@ DMA810 (octyl/decyl dimethylamines); Fentamine@ DMA818 (cocoalkyl dimethylamines); Fentamine@ DMA1095 (decyl dimethylamine); Fentamine@ DMA1297 (dodecyl dimethylamine); Fentamine@ DMA1497 (tetradecyl dimethylamine); Fentamine@ DMA1697 (hexadecyl dimethylamine); Fentamine@ DMA1895 (octadecyl dimethylamine); Fentamine@ DMA1270 (dodecyl/tetradecyl dimethylamines); Fentamine@ DMA1265 (dodecyl/tetradecyl dimethylamines); Fentamine@ DMA1263 (dodecyl/tetradecyl dimethylamines); Fentamine@ DMA1450 (dodecyl/tetradecyl dimethylamines); Fentamine@ DMA121416 (dodecyl/tetradecyl dimethylamines); Fentamine@ DMA1218 (cocoalkyl dimethylamines); Fentamine@ DMA1816 (octadecyl/hexadecyl dimethylamines); Fentamine@ DMA2275 (octadecyl/behenyl dimethylamines); Fentamine@ DMA22 (behenyl dimethylamine); and Fentamine@ DMAO (oleyl dimethylamine). In an embodiment, the amines are selected from the group consisting of the Fentamine@ group of dialkyl tertiary amines: Fentamine@ MA88 (dioctyl methylamine); Fentamine@ MA810 (di(octyl/decyl) methylamines); Fentamine@ MA1010 (didecyl methylamine); Fentamine@ MA1212 (didodecyl methylamine); Fentamine@ MA1616 (dihexadecyl methylamine); Fentamine@ MA1816 (di(octadecyl/hexadecyl) methylamines); Fentamine@ MA DHT (di(hydrogenated tallowalkyl) methylamines); and Fentamine@ MA DCO (dicocoalkyl methylamines). In an embodiment, the amines are selected from the group consisting of the Fentamine@ group of trialkyl tertiary amines: Fentamine@ TA8 (trioctylamine); Fentamine@ TA0810 (tri(octyl/decyl)amines); Fentamine@ TA12 (tridodecylamine); and Fentamine@ TA16 (trihexadecylamine). In an embodiment, the tertiary amines are selected from the Ablemarle@ group of amines: AMDA@ 18 amine (octadecyldimethylamine). In an embodiment, the one or more tertiary amine compounds can comprise a mixture of different alkyl chain lengths. Many suitable amines that are available commercially are not pure compounds. They are often mixtures of compounds, for example having different alkyl chain lengths. In an embodiment, the amine is DMAMP (2-dimethylamino-2-methyl-1 propanol). In an embodiment, the preservative is selected from the group consisting of: insecticides, termiticides, fungicides, mouldicides, or the like, and mixtures thereof. In an embodiment, the preservative is a triazole compound of formulae (I) or (II): OH O 3 R2-CH 2 -CH 2 R1

OH 2 R4 0 OH2

N N N N N / (I) N ()

wherein R 1 represents a branched or straight chain C 15_ alkyl group; R 2

represents a phenyl group optionally substituted by one or more substituents selected from halogen, C1_3alkyl, C1_ 3 alkoxy, phenyl and nitro; R 3 is as defined for R 2 ; and R4 represents a hydrogen atom or a branched or straight chain C 1_alkyl. In an embodiment, the triazole compound of formula (I)is tebuconazole (a-[2 (4-chlorophenyl)ethyl]-a-(1,1-dimethylethyl)-1H-1,2,4-triazole-l-ethanol) or hexaconazole (a-butyl-a-(2,4-dichlorophenyl)-1H-1,2,4-triazole-1-ethanol). Most preferably, the triazole compound of formula (I) is tebuconazole. In an embodiment, the triazole compound of formula (II) is propiconazole (1

[[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl]methyl]-lH-1,2,4-triazole); azaconazole (1-[[2,4-dichlorophenyl)-1,3-dioxolan-2-yl]methyl]-lH-1,2,4-triazole); or difenaconazole (1-[2-[2-chloro-4-(4-chlorophenoxy)phenyl]-4-methyl-1,3-dioxolan-2- ylmethyl]-1H-1,2,4-triazole). In an embodiment, the preservative is a triazole compound selected from the group consisting of: azaconazole, bromuconazole, cyproconazole, diclobutrazol, difenoconazole, diniconazole, diniconazole-M, epoxiconazole, etaconazole, fenbuconazole, fluquinconazole, flusilazole, flutriafol, furconazole, furconazole-cis, hexaconazole, imibenconazole, ipconazole, metconazole, myclobutanil, penconazole, propiconazole, prothioconazole, quinconazole, simeconazole, tebuconazole, tetraconazole, triadimefon, triadimenol, triticonazole, uniconazole, and uniconazole-P and their metal salts and acid adducts, or mixtures thereof. In an embodiment, the preservative is a fungicide selected from azaconazole, tebuconazole, propiconazole, cyproconazole, hexaconazole, triadamefon, 4,5-dichloro 2-n-octyl-4-isothiazolin-3-one (DCOIT), didecyldimethylammonium chloride, didecyldimethylammonium carbonate/bicarbonate, benzalkonum chloride, penflufen, 3-iodo-2-propynyl-butylcarbamate (IPBC), copper naphthenate, copper oxine, copper octanoate, copper soaps, zinc naphthenate, zinc octanoate, zinc soaps, tributyltin naphthenate, chlorothalonil, pentachlorophenol. In an embodiment, the one or more preservative compounds are selected from propiconazole, tebuconazole, cyproconazole and their metal salts and acid adducts, or mixtures thereof. In an embodiment, the inventive formulation comprises propiconazole and tebuconazole is an approximate 1:1 ratio by weight. In an embodiment, the one or more preservative compounds are selected from quaternary ammonium compounds such as didecyldimethylammonium chloride, didecyldimethylammonium bicarbonate/carbonate, and/or other didecyldimethylammonium salts, or benzalkonium chloride. In an embodiment, the quaternary ammonium compounds are selected from didecyldimethylammonium chloride, didecylmethylpoly(oxyethyl)ammonium chloride and/or didecyldimethylammonium bicarbonate/carbonate. In an embodiment, the one or more preservative compounds are metal-based compounds, selected from metal naphthenates such as copper naphthenate, zinc naphthenate or tributyltin naphthenate, metal abietates such as copper abietate or zinc abietate, metal soaps of tall oil fatty acids, metal soaps such as copper bis(2- ethylhexanoate), zinc bis(2-ethylhexanoate) or metal chelates of 8-hydroxyquinolate such as copper 8-hydroxyquinolate, metal oxides such as cupric and cuprous oxide and zinc oxide, metal chlorides such as copper chloride or zinc chloride, metal sulfates such as copper sulfate or zinc sulfate, metal hydroxides such as copper hydroxide or zinc hydroxide, carbonates such as basic copper carbonate or zinc carbonate, borates such as copper borate or zinc borate. In an embodiment, the one or more preservative compounds are selected from copper naphthenate, zinc naphthenate and/or copper oxine. In an embodiment, the one or more preservative compounds may be in soluble and/or micronised/dispersed forms. In an embodiment, the inventive formulation comprises a non-aqueous dispersion of a copper compound. Preferably, the copper compound is a copper(II) compound. In an embodiment, the one or more preservative compounds are anti-fungal compounds selected from phenols such as pentachlorophenol, 2,4,5-trichlorophenol, 2,4,6-trichlorophenol, ortho-, meta- or para-cresol, 2-benzyl-4-chorophenol, 4-chloro 3,5-dimethylphenol, 2-(4-chlorophenoxy)ethanol, ortho-phenylphenol, 5-chloro-2-(4 chlorophenoxy)phenol, and salts thereof. In an embodiment, the one or more preservative compounds are anti-fungal compounds selected from isothiazolinones such as 1,2-benzisothiazolin-3-one (BIT); 2-methyl-1,2-benzothiazolin-3(2H)-one (MBIT); 2-butyl-1,2-benzothiazolin-3(2H) one (BBIT); 5-chloro-2-methyl-4-isothiazolin-3-one (CMIT); 2-methyl-4-isothiazolin 3-one (MIT); mixtures of CMIT and MIT; 4,5-dichloro-2-octyl-4-isothiazolin-3-one (DCOIT); 2-octyl-4-isothiazolin-3-one (OIT), and mixtures thereof. In an embodiment, the one or more preservative compounds is a succinate dehydrogenase inhibitor (SDHI) compound such as carboxamide compounds selected from the group consisting of benalaxyl, benalaxyl-M, benodanil, bixafen, boscalid, carboxin, fenfuram, fenhexamid, flutolanil, fluxapyroxad, furametpyr, isopyrazam, isotianil, kiralaxyl, mepronil, metalaxyl, metalaxyl-M (mefenoxam), ofurace, oxadixyl, oxy- carboxin, penflufen, penthiopyrad, sedaxane, tecloftalam, thifluzamide, tiadinil, 2- amino-4-methyl-thiazole-5-carboxanilide, N-(4' trifluoromethylthiobiphenyl-2-yl)- 3-difluoromethyl-1 -methyl-1 H-pyrazole-4- carboxamide and N-(2-(1,3,3-trimethyl- butyl)-phenyl)-1,3-dimethyl-5-fluoro-1 H pyrazole-4-carboxamide; dimethomorph, flumorph, pyrimorph, flumetover, fluopicolide, fluopyram, zoxamide; carpropamid, dicyclomet, mandiproamid, oxytetracyclin, silthiofam, N-(6-methoxy-pyridin-3-yl) cyclopropanecarboxylic acid amide, niacinamide and mixtures thereof. In an embodiment, the one or more preservative compounds are anti-fungal compounds selected from: 3-iodo-2-propynyl butyl carbamate; thiocyanomethylthiobenzothiazole (TCMTB); MBT; chlorothalonil; creosote and mixtures thereof. In an embodiment, the one or more anti-fungal compounds is creosote. In an embodiment, the inventive formulation further comprises anti-foamers, water repellent components, colour additives or penetration marker compounds. In an embodiment, the penetration to the formulation within the treated wood is by way of substantially complete penetration. In an embodiment, the substantially complete penetration is in accordance with Hazard Classes H3 and H4 of the Australian Standard AS 1604-2012 series. In an embodiment, the treated wood is classifiable in the art as "dry after" (moisture content <20% w/w) following treatment with said formulation. In an embodiment, the treated wood does not require a subsequent drying operation. In an embodiment, the treated wood is substantially not susceptible to leaching of the preservative from said wood. In an embodiment, the treated wood has relatively constant dimensional stability as a result of the non-aqueous carrier remaining within the cells of the treated wood. In an embodiment, the formulation is applicable to hardwood and/or softwood species. In another embodiment, the formulation is applicable to wood composites selected from the group consisting of: particle board, medium density fibreboard (MDF), oriented strand board (OSB), plywood, laminated veneer lumber (LVL), glue laminated lumber or cross laminated lumber. In an embodiment, the inventive formulation optionally comprises surfactants/emulsifiers, other co-solvents, mouldicides, fire retardants, anti-foam agents, water repellent components, colour additives, adhesion promoters, penetration marker compounds or other additives. In an embodiment, the weight ratio of the preservative to potentiator is about 100:1 to about 1:100. More preferably, the weight ratio of the preservative to potentiator is about 50:1 to about 1:50. More preferably still, the weight ratio of the preservative to potentiator is about 10:1 to about 1:10. More preferably, the weight ratio of the preservative to potentiator is about 1:1 to about 1:6. Most preferably, the weight ratio of the preservative to potentiator is about 1:3. In an embodiment, the inventive formulation optionally comprises an additional antimicrobial component. In an embodiment, the addition antimicrobial component comprises at least on component selected from the group consisting of at least one further compound from the group benzimidazoles, imidazoles, morpholine derivatives, copper compounds, pyrethroids, triazoles, sulfonamides, boron compound, pyrithione compounds and mixture thereof. In an embodiment, the additional antimicrobial component comprises zinc pyrithione. According to an especially preferred embodiment of the first aspect of the invention, the inventive formulation comprises about 4.5 g/L tebuconazole, about 4.5 g/L propiconazole, and about 9 g/L of an approximate 95% C18 alkyldimethylamine (such as Barlene@ 18S (N,N-dimethyloctadecylamine, dimantine). According to an especially preferred embodiment of the first aspect of the invention, the inventive formulation comprises about 4.5 g/L tebuconazole, about 4.5 g/L propiconazole, and about 18 g/L of an approximate 95% C18 alkyldimethylamine (such as Barlene@ 18S (N,N-dimethyloctadecylamine, dimantine). According to an especially preferred embodiment of the first aspect of the invention, the inventive formulation comprises about 4.5 g/L tebuconazole, about 4.5 g/L propiconazole, and about 27 g/L of an approximate 95% C18 alkyldimethylamine (such as Barlene@ 18S (N,N-dimethyloctadecylamine, dimantine). According to an especially preferred embodiment of the first aspect of the invention, the inventive formulation comprises about 4.5 g/L tebuconazole, about 4.5 g/L propiconazole, and about 36 g/L of an approximate 95% C18 alkyldimethylamine (such as Barlene@ 18S (N,N-dimethyloctadecylamine, dimantine). According to an especially preferred embodiment of the first aspect of the invention, the inventive formulation comprises about 4.5 g/L tebuconazole, about 4.5 g/L propiconazole, and about 45 g/L of an approximate 95% C18 alkyldimethylamine (such as Barlene@ 18S (N,N-dimethyloctadecylamine, dimantine). According to an especially preferred embodiment of the first aspect of the invention, the inventive formulation comprises about 4.5 g/L tebuconazole, about 4.5 g/L propiconazole, and about 54 g/L of an approximate 95% C18 alkyldimethylamine (such as Barlene@ 18S (N,N-dimethyloctadecylamine, dimantine). According to an especially preferred embodiment of the first aspect of the invention, the inventive formulation comprises about 4.5 g/L tebuconazole, about 4.5 g/L propiconazole, and about 90 g/L of an approximate 95% C18 alkyldimethylamine (such as Barlene@ 18S (N,N-dimethyloctadecylamine, dimantine). In an embodiment, the non-aqueous carrier is selected from the group consisting of: white spirit, kerosene, low aromatic solvents and mixtures thereof. In another embodiment, the non-aqueous carrier comprises a solvent mixture, itself comprising water combined with a hydrocarbon fraction. According to a second aspect of the present invention there is provided a method of treating a substrate of wood or other cellulosic material by applying to the substrate a preservative formulation as defined according to the first aspect of the present invention. In an embodiment, the step of contacting the wood is performed by means selected from the group consisting of: pressure application, spraying, dipping, rolling, painting, or any combination thereof. In an embodiment, the preservative and amine potentiator are applied to the wood in separate, sequential steps, either fungicide followed by amine; or amine followed by fungicide. In an embodiment, the wood is less than about 25 mm in thickness. In another embodiment, the inventive method further comprises at least one vacuum step. Preferably, the vacuum step is between about 0 and -50 kPa. In another embodiment, the inventive method further comprises at least one pressure step. Preferably, the pressure step is between about 0 and 200 kPa. In another embodiment, each of the vacuum and/or pressure steps is held for between about 0 and 10 minutes.

In another embodiment, dimensional changes between the wood prior to and post the treatment are no greater than about 2 mm in any or either cross-sectional dimension. In another embodiment, a final vacuum step is applied, the final vacuum step taking place when the wood is no longer exposed to the preservative formulation. Preferably, the final vacuum step is between about 0 and -95 kPa and is held from about 0 to 60 minutes. According to a third aspect of the present invention there is provided treated wood, when so-treated by a method defined according to the second aspect of the present invention. According to a fourth aspect of the present invention there is provided a method of preparing a wood preservative formulation as defined according to the first aspect of the present invention, the method comprising the steps of admixing: a non aqueous carrier; one or more preservative compounds; and one or more tertiary amine compounds. Generally, the fungicide to potentiator mixture is in the range of a ratio of about 100:1 to about 1:100 on a weight basis. Typically, the ratio of fungicide to potentiator will be in the range of a ratio 50:1 to about 1:50 on a weight basis. More typically the ratio of the components will be in the range of about 10:1 to about 1:10 on a weight basis of the fungicide to potentiator. The actual ratios will depend on the potentiator and the particular fungicide selected, however, with reference to Examples 5-11, below, exemplary w/w ratios of fungicide to potentiator are of the order of approximately 1:1 to approximately 1:6. It has been discovered that the composition of the fungicide and the potentiator is more effective against organisms, than the fungicide compound/s alone. Exemplary organisms which the composition has of the present invention are effective against, include, but are not limited to, Botrytis spp, Rhizopus spp, Penicilliumspp., Cladosporiumspp., Aspergillus spp, including, for example, Aspergillus niger, and Aspergillusflavus, Alternaria spp., Fusariumspp., Aerobasidium spp., and Trichoderma spp. In addition to the fungicide and the potentiator, the inventive formulation may further have additional compounds or components which serve as biocidal components. These additional compounds or components essentially as co-biocides in the formulation. The additional biocidal component may be selected based on the activity of the particular component or on the use of the resulting formulation. In the case of wood, such as timber, lumber, and other wood products such as plywood, particle board, fiberboard and oriented strand board (OSB) and wood composites (plastic-wood), the additional compounds or components may be compounds or compositions which are known to have fungicidal, bactericidal or insecticidal properties. Suitable additional components include, for example benzimidazoles, imidazoles, morpholine derivatives, copper compounds, pyrethroids, triazoles, sulfenamides, boron compounds, pyrithione compounds, tertiary amines, haloalkynyl compounds, quaternary ammonium compounds, phenols, pyrroles, strobilurins, phenylsulfamides, zinc compounds and mixtures thereof. Other similar compounds or classes of compounds may be used. Selection of a suitable additional component or co-biocide for a given purpose will be readily apparent to those skilled in the art. In addition, other compounds and compositions have which are known to have fungicidal properties may be added. Suitable fungicides include, for example: (3 ethoxypropyl)mercury bromide; 2-methoxyethylmercury chloride; 2-phenylphenol; 8 hydroxyquinoline sulfate; 8-phenylmercurioxyquinoline; acibenzolar; acylamino acid fungicides; acypetacs; aldimorph; aliphatic nitrogen fungicides; allyl alcohol; amide fungicides; ampropylfos; anilazine; anilide fungicides; antibiotic fungicides; aromatic fungicides; aureofungin; azaconazole; azithiram; azoxystrobin; barium polysulfide; benalaxyl; benalaxyl-M; benodanil; benomyl; benquinox; bentaluron; benthiavalicarb; benzalkonium chloride; benzamacril; benzamide fungicides; benzamorf; benzanilide fungicides; benzimidazole fungicides; benzimidazole precursor fungicides; benzimidazolylcarbamate fungicides; benzohydroxamic acid; benzothiazole fungicides; bethoxazin; binapacryl; biphenyl; bitertanol; bithionol; bixafen; blasticidin-S; Bordeaux mixture; boric acid; boscalid; bridged diphenyl fungicides; bromuconazole; bupirimate; Burgundy mixture; buthiobate; sec-butylamine; calcium polysulfide; captafol; captan; carbamate fungicides; carbamorph; carbanilate fungicides; carbendazim; carboxin; carpropamid; carvone; Cheshunt mixture; chinomethionat; chlobenthiazone; chloraniformethan; chloranil; chlorfenazole; chlorodinitronaphthalene; chloroform; chloroneb; chloropicrin; chlorothalonil; chlorquinox; chlozolinate; ciclopirox; climbazole; clotrimazole; conazole fungicides; conazole fungicides (imidazoles); conazole fungicides (triazoles); copper(II) acetate; copper(II) carbonate, basic; copper fungicides; copper hydroxide; copper naphthenate; copper oleate; copper oxychloride; copper(II) sulfate; copper sulfate, basic; copper zinc chromate; cresol; cufraneb; cuprobam; cuprous oxide; cyazofamid; cyclafuramid; cyclic dithiocarbamate fungicides; cycloheximide; cyflufenamid; cymoxanil; cypendazole; cyproconazole; cyprodinil; dazomet; DBCP; debacarb; decafentin; dehydroacetic acid; dicarboximide fungicides; dichlofluanid; dichlone; dichlorophen; dichlorophenyl; dichlozoline; diclobutrazol; diclocymet; diclomezine; dicloran; diethofencarb; diethyl pyrocarbonate; difenoconazole; diflumetorim; dimethirimol; dimethomorph; dimoxystrobin; diniconazole; diniconazole-M; dinitrophenol fungicides; dinobuton; dinocap; dinocap-4; dinocap-6; dinocton; dinopenton; dinosulfon; dinoterbon; diphenylamine; dipyrithione; disulfiram; ditalimfos; dithianon; dithiocarbamate fungicides; DNOC; dodemorph; dodicin; dodine; donatodine; drazoxolon; edifenphos; epoxiconazole; etaconazole; etem; ethaboxam; ethirimol; ethoxyquin; ethylene oxide; ethylmercury 2,3-dihydroxypropyl mercaptide; ethylmercury acetate; ethylmercury bromide; ethylmercury chloride; ethylmercury phosphate; etridiazole; famoxadone; fenamidone; fenaminosulf; fenapanil; fenarimol; fenbuconazole; fenfuram; fenhexamid; fenitropan; fenoxanil; fenpiclonil; fenpropidin; fenpropimorph; fentin; ferbam; ferimzone; fluazinam; Fluconazole; fludioxonil; flumetover; flumorph; fluopicolide; fluoroimide; fluotrimazole; fluoxastrobin; fluquinconazole; flusilazole; flusulfamide; flutolanil; flutriafol; fluxapyroxad; folpet; formaldehyde; fosetyl; fuberidazole; furalaxyl; furametpyr; furamide fungicides; furanilide fungicides; furcarbanil; furconazole; furconazole-cis; furfural; funnecyclox; furophanate; glyodin; griseofulvin; guazatine; halacrinate; hexachlorobenzene; hexachlorobutadiene; hexachlorophene; hexaconazole; hexylthiofos; hydrargaphen; hymexazol; imazalil; imibenconazole; imidazole fungicides; iminoctadine; inorganic fungicides; inorganic mercury fungicides; iodomethane; ipconazole; iprobenfos; iprodione; iprovalicarb; isopropyl alcohol; isoprothiolane; isovaledione; kasugamycin; kresoxim-methyl; Lime sulfur (lime sulphur); mancopper; mancozeb; maneb; mebenil; mecarbinzid; mepanipyrim; mepronil; mercuric chloride; mercuric oxide; mercurous chloride; mercury fungicides; metalaxyl; metalaxyl-M (a.k.a. Mefenoxam); metam; metazoxolon; metconazole; methasulfocarb; methfuroxam; methyl bromide; methyl isothiocyanate; methylmercury benzoate; methylmercury dicyandiamide; methylmercury pentachlorophenoxide; metiram; metominostrobin; metrafenone; metsulfovax; milneb; morpholine fungicides; myclobutanil; myclozolin; N (ethylmercury)-p-toluenesulfonanilide; nabam; natamycin; nystatin;3-nitrostyrene; nitrothal-isopropyl; nuarimol; OCH; octhilinone; ofurace; oprodione; organomercury fungicides; organophosphorus fungicides; organotin fungicides; orthophenyl phenol; orysastrobin; oxadixyl; oxathiin fungicides; oxazole fungicides; oxine copper; oxpoconazole; oxycarboxin; pefurazoate; penconazole; pencycuron; pentachlorophenol; penthiopyrad; phenylmercuriurea; phenylmercury acetate; phenylmercury chloride; phenylmercury derivative of pyrocatechol; phenylmercury nitrate; phenylmercury salicylate; phenylsulfamide fungicides; phosdiphen; Phosphite; phthalide; phthalimide fungicides; picoxystrobin; piperalin; polycarbamate; polymeric dithiocarbamate fungicides; polyoxins; polyoxorim; polysulfide fungicides; potassium azide; potassium polysulfide; potassium thiocyanate; probenazole; prochloraz; procymidone; propamocarb; propiconazole; propineb; proquinazid; prothiocarb; prothioconazole; pyracarbolid; pyraclostrobin; pyrazole fungicides; pyrazophos; pyridine fungicides; pyridinitril; pyrifenox; pyrimethanil; pyrimidine fungicides; pyroquilon; pyroxychlor; pyroxyfur; pyrrole fungicides; quinacetol; quinazamid; quinconazole; quinoline fungicides; quinomethionate; quinone fungicides; quinoxaline fungicides; quinoxyfen; quintozene; rabenzazole; salicylanilide; silthiofam; silver; simeconazole; sodium azide; sodium bicarbonate; sodium orthophenylphenoxide; sodium pentachlorophenoxide; sodium polysulfide; spiroxamine; streptomycin; strobilurin fungicides; sulfonanilide fungicides; sulfur; sulfuryl fluoride; sultropen; TCMTB; tebuconazole; tecloftalam; tecnazene; tecoram; tetraconazole; thiabendazole; thiadifluor; thiazole fungicides; thicyofen; thifluzamide; thymol; triforine; thiocarbamate fungicides; thiochlorfenphim; thiomersal; thiophanate; thiophanate methyl; thiophene fungicides; thioquinox; thiram; tiadinil; tioxymid; tivedo; tolclofos methyl; tolnaftate; tolylfluanid; tolylmercury acetate; triadimefon; triadimenol; triamiphos; triarimol; triazbutil; triazine fungicides; triazole fungicides; triazoxide; tributyltin oxide; trichlamide; tricyclazole; tridemorph; trifloxystrobin; triflumizole; triforine; triticonazole; unclassified fungicides; Undecylenic acid; uniconazole; uniconazole-P; urea fungicides; validamycin; valinamide fungicides; vinclozolin; voriconazole; zarilamid; zinc naphthenate; zineb; ziram; zoxamide. The fungicide/potentiator of the present invention may be used in the customary formulations, such as solutions, emulsions, suspensions, powders, foams, pastes, granules, aerosols and very fine capsules in polymeric substances. It is also possible to encapsulate the fungicide/potentiator and/or additional biocide. In addition, by mixing the active compounds with extenders, such as liquid solvents, liquefied gases under pressure and/or solid carriers, and optionally with the use of surfactants, emulsifiers and/or dispersants, the composition may be applied to a surface or article in need of treatment. Suitable solvents include, water, organic solvents such as, for example, xylene, toluene or alkyl naphthalenes, chlorinated aromatics or chlorinated aliphatic hydrocarbons, such as chlorobenzenes, chloride or methylene chloride, aliphatic hydrocarbons such as cyclohexane or paraffins, for example petroleum fractions, alcohols, such as butanol, glycerol, and ethers and esters, ketones, such as acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone, strongly polar solvents such as dimethylformamide and dimethylsulfoxide, as well as water. Liquefied gaseous extenders or carriers are meant liquids which are gaseous at normal temperature and under normal pressure, for example aerosol propellants, such as halogenated hydrocarbons as well as butane, propane, nitrogen and carbon dioxide. Suitable solid carriers are: for example ground natural minerals, such as kaolins, clays, talc, chalk, quartz, attapulgite, montmorillonite or diatomaceous earth, and ground synthetic minerals, such as highly disperse silica, alumina and silicates. As solid carriers for granules are: for example crushed and fractionated natural rocks such as calcite, marble, pumice, sepiolite and dolomite, and synthetic granules of inorganic and organic meals, and granules of organic material such as sawdust, coconut shells, maize cobs and tobacco stalks. As emulsifying and / or foam formers are: for example nonionic and anionic emulsifiers, such as polyoxyethylene fatty acid esters, polyoxyethylene fatty alcohol ethers, for example alkylaryl, alkyl sulfates, aryl sulfonates as well as albumin. Suitable dispersants are: for example ligninsulfite was liquors and methylcellulose.

It has been discovered that formulations of one or more anti-fungal compound/s and a tertiary amine are more effective against certain organisms than the anti-fungal compound/s alone. Exemplary organisms for which the composition of the present invention are effective against, include, but are not limited to: Fomotopsis lilacino-gilva, Coniophoraolivacea, Antrodia sinuosa, Antrodia xantha and Fomotopsispalustris. Amines suitable for use as a potentiator include, but are not limited to: myristylamine, Tomamine d16 (C 16 alkyl ether amine), Tomamine d14 (C1 4 alkyl ether amine), N,N-dimethyldecanamine, N,N-dimethyloctylamine, dimethyloctadecylamine, diisoproanolamine, oleylamine, ethanolamine, ethoxylated amines, such as, N,N',N' polyoxyethylene(15)-N-tallowalkyl-1,3-diaminopropane, and mixtures thereof. Those suitably skilled in the art will appreciate that other similar amines may also be used without departing from the spirit and the scope of the present invention. It will also be well understood that the fungicides can be used with insecticides and other additives, e.g., formulation additives (co-solvents), mouldicides, colourants (dyes, pigments), water repellents (resins, waxes), penetration markers, etc.

Brief Description of the Figures A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 shows the results from a laboratory bioassay carried out in accordance with recognised methods (see, Protocolsforthe Assessment of Wood Preservatives, Australasian Wood Preservation Committee, March 2007 Revision, Ensis, Clayton). In these tests, Radiatapine sapwood (20 x 20 x 10 mm) specimens were treated with various preservative formulations. After drying, the specimens were saturated with water and leached in a shaking water bath at 35 C for seven days, with daily changes of water. After leaching, the specimens were vacuum oven-dried, before being sterilised in readiness for the fungal bioassay. The specimens were then placed in the soil jars, which had previously been inoculated with the chosen decay fungus, and the jars were incubated under conditions ideal for decay for a period of approximately 12 weeks. After incubation the specimens were cleaned, weighed and their mass loss determined.

Mass loss, expressed as a percentage, was used to determine the effectiveness of the preservative treatment. In general, the more effective the preservative treatment, the lower the mass loss. Decay is deemed to have been prevented if the mass loss is less than 3%. In Figure 1 the results (mean percentage mass loss) are shown for test specimens exposed to a brown rot decay fungus, Fomotopsis lilacino-gilva, for 12 weeks. "UTC" = untreated control; "STC" = solvent treated control, "CEl" = ComparativeExample ] (azole-only formulation); "5-11" = formulations 5-11 from Examples 5-11, respectively (see, below). The test specimens all contained 0.03% m/m total azoles (i.e., propiconazole and tebuconazole, 1:1). Figure 1 demonstrates that as the amount of alkyldimethylamine present in the formulation is increased, so too is its potentiating effect upon the azole mixture (propiconazole/ tebuconazole, 1:1). An optimal effect was observed in Example 10, wherein the w/w ratio of combined azoles to amine was about 1:6. It should also be noted that the tertiary amine alone offers little resistance to decay. Radiata pine sapwood specimens treated with a non-aqueous solution of only alkyldimethylamine (octadecyldimethylamine) and exposed to F. lilacino-gilvaby the same procedure as described above were heavily decayed. For example, the mean mass loss for six replicates treated to 0.18% m/m with octadecyldimethylamine was 25%. Additional results are shown in Figure 2; the only difference being the decay organism to which the specimens were exposed. In this example the specimens were exposed to Antrodia xantha. The abbreviations used in Figure 2 have the same meaning as those used in Figure 1. The test specimens all contained 0.03% m/m total azoles, with varying amounts of tertiary amine (total azole to tertiary amine ratio of 1:1 through to 1:6). The specimens treated with formulations 5-11 all controlled decay (<3% mass loss) whereas the azole only formulation, CEl, did not prevent decay of the softwood specimens. This example further demonstrates the utility of the invention to control a range of organisms. Moreover, the benefit of incorporation of tertiary amines into solvent-based preservative treatments is also evident from the performance of the treated timber against mould fungi. Fungicides that protect wood against decay vary in their ability to keep wood free of mould species, such as Trichoderma spp., Penicilliumspp., Cladosporiumspp., Aspergillus spp, Alternaria spp., Fusariumspp., Aerobasidium spp. etc. Although mould infection does not affect the structural properties of the timber, it can detract from its value hence it is advantageous to prevent mould growth on treated timber, particularly through the chain of commerce. The tertiary amines themselves have weak activity against mould fungi in solvent-based treatments at the concentrations used in the examples described herein, however the combination of fungicide and tertiary amine provides improved anti-fungal activity. Examples 12-18 below illustrate enhanced efficacy against mould fungi. In these tests, sets of end-sealed radiata pine sapwood (40 x 40 x 10 mm) were treated with either: (i) white spirit formulations containing a fungicide; (ii) white spirit formulations containing a tertiary amine or (iii) white spirit formulations containing a fungicide and a tertiary amine. Untreated controls and controls treated with solvent only were also included in the bioassays. After treatment the specimens were aired in a manner that allowed the solvent to slowly evaporate. The specimens were evaluated for their resistance to develop mould, using a method adapted from the American Wood Protection Association (AWPA) Standard E24-12, Standardmethod of evaluating the resistanceof wood product surfaces to mould growth. Periodically the specimens were inspected and assessed for infection, by estimating the proportion of the surface of each specimen infected by mould or stain fungi, expressed as a percentage (%), ranging from 0 (no visible mould) to 100 (surface entirely infected with mould). Additionally, the benefit of incorporation of tertiary amines into solvent-based preservative treatments is also evident from the performance of the treated timber against insects such as termites (e.g., Mastotermes darwiniensis). Example 19 illustrates that tertiary amines also enhanced the insecticidal activity of a synthetic pyrethroid, permethrin. Figure 3 illustrates mass loss as a function of treatment type for radiata pine sapwood, exposed to Mastotermes darwiniensisin an above-ground field test. As shown, preservative fungicides in each of the treated sets are "TP" is tebuconazole/propiconazole (1/1), retention = 0.06%m/m azole. "Amine" is stearyl dimethylamine, retention = 0.18%m/m. Permethrin retention is 0.005%m/m in each preservative treated set shown.

Examples Example 1:

Wood preservativeformulation - C14, tetradecyldimethylamine Table ] Raw Material Concentration (g/L) Tebuconazole 4.5 Propiconazole 4.5 Permethrin 3.3 Alkyldimethylamine, where the alkyl group is 27 comprised (approximately) of 95% C14 Co-solvent (e.g., glycol ether) 20 Water repellent 34 White spirit Balance

Example 2: Wood preservativeformulation - C16, hexadecyldimethylamine Table 2 Raw Material Concentration (g/L) Tebuconazole 4.5 Propiconazole 4.5 Permethrin 3.3 Alkyldimethylamine, where the alkyl group is 27 comprised (approximately) of 95% C16 Co-solvent (e.g., glycol ether) 20 Water repellent 34 White spirit Balance

Example 3: Wood preservativeformulation - C18, octadecyldimethylamine Table 3 Raw Material Concentration (g/L) Tebuconazole 4.5 Propiconazole 4.5 Permethrin 3.3 Alkyldimethylamine, where the alkyl group is 27 comprised (approximately) of 95% C18 Co-solvent (e.g., glycol ether) 20 Water repellent 34 White spirit Balance

The anti-fungal efficacy of the formulations given in Examples 1 to 3 were compared, along with that of Comparative Example 1, in a laboratory bioassay performed using an identical procedure to that described above for the example shown in Figure 1. The substrate was again radiata pine sapwood and the total azole retention in the sets of specimens treated with ComparativeExample 1 and Examples 1 to 3 was 0.03% m/m. The results of the bioassay, where the specimens were exposed to the brown rot decay fungus F. lilacino-gilva,are shown in Table 4.

Table 4

Total azole retention Tertiary amine Mean mass Treatment formulation

Untreated control 0 71.5 Comparative example 1 0.03 38.4 Example 1 0.03 Tetradecyldimethylamine 15.2 Example 2 0.03 Hexadecyldimethylamine 11.2 Example 3 0.03 Octadecyldimethylamine 3.8

The results in Table 4 demonstrate that all of the formulations described in Examples 1 to 3 were more efficacious through the incorporation of the tertiary amine, and that the effectiveness of the tertiary amine increases with increasing carbon chain length on the alkyl group.

ComparativeExample 1: Comparativewood preservativeformulation containing active ingredients only Table 5 Raw Material Concentration (g/L) Tebuconazole 4.5 Propiconazole 4.5 Permethrin 3.3 Co-solvent (e.g., glycol ether) 20 Water repellent 34 White spirit Balance

The formulation shown in Comparative Example 1, containing a 1:1 w/w mixture of propiconazole and tebuconazole, was used to treat radiatapine sapwood specimens and these specimens were exposed to a decay fungus, A. xantha, using an identical procedure to that described above for the example shown in Figure 1. Untreated and solvent-treated samples were observed to decay markedly (56.7 and 55.1%, respectively). By comparison, at a retention of 0.03% m/m total azole (propiconazole and tebuconazole, 1:1), decay was reduced somewhat (26.5%), while increasing the total azole retention to 0.06 %m/m further reduced the decay in the specimens (8.7%). In conclusion, it is clear that timber treated with a 1:1 w/w mixture of propiconazole and tebuconazole has some resistance to A. xantha over a 12 week period. However, specimens treated to the higher retention (0.06% m/m) were decayed (8.7% mass loss) significantly above the above-mentioned decay threshold of 3%, such that the triazole combination is not completely effective at controlling this organism at retentions up to 0.06% m/m in timber.

Table 6

Total azole Amine retention Mass Loss Treatment formulation retention (% m/m) (% m/m) (%) Untreated radiatapine control -_-_56.7 Solvent-treated radiatapine control - 55.1 Comparative Example 1 0.03 - 26.5 Comparative Example 1 0.06 - 8.7

Example 4: Inventive formulation versus fungicide sans potentiator Table 7

Total azole retention Amine retention Mass Loss Treatment (% m/m) (% m/m) (%) Untreated radiata pine control - 56.7 Solvent-treated radiata pine control - - 55.1 Propiconazole, tebuconazole (1:1)A 0.03 - 26.5 combination Propiconazole, tebuconazole (1:1)A 0.06 - 8.7 combination Propiconazole, tebuconazole (1:1) 0.03 0.09 1.0 combination and C18NMe2 Propiconazole, tebuconazole (1:1) 0.06 0.18 0.3 combination and C18NMe2 A See, Comparative Example 1

4 C18NMe 2 = Barlene@ 18S (i.e., stearyl dimethyl amine)

Example 4 provides the results of a laboratory bioassay carried out in accordance with recognised methods, as described above for Figure 1. Table 7 summarises the comparative data provided above, with data obtained for the inventive formulation comprising the potentiator. Timber treated with the 1:1 combination of propiconazole and tebuconazole at retentions of 0.03 and 0.06% m/m (total azole) were found to be decayed by A. xantha, with mean mass losses of 26.5 and 8.7%, respectively.

However, the incorporation of an amine in the form of octadecyldimethylamine (and minor quantities of other amines) at an amount to give a total azole to amine w/w ratio of 1:3 reduced the mass loss significantly. In the case of specimens containing an azole retention of 0.03% m/m, the mass loss was reduced from 26.5% to 1.0%, i.e., decay was prevented significantly through the incorporation of the octadecyldimethylamine tertiary amine. Example 4 shows conclusively, that the presence of a tertiary amine potentiates the antifungal effect of the azole mixture (tebuconazole/propiconazole 1:1). As explained elsewhere, the tertiary amine itself elicits no significant antifungal activity, which corroborates the Applicant's claim of a potentiating effect. The decay results observed for the 0.03 and 0.06% m/m tebuconazole/propiconazole/ Barlene@ 18S treated samples (1.0 and 0.3% mass loss, respectively) are comfortably within the 3% threshold under which decay is said to have been prevented.

Examples 5-11: Wood preservativeformulations containing varying amounts of the tertiary amine, alkyldimethylamine, where the alkyl group is comprised of approximately 95% C1 8 Table 8 Example 5 6 7 8 9 10 11 Raw Material Concentration (g/L) Tebuconazole 4.5 4.5 4.5 4.5 4.5 4.5 4.5 Propiconazole 4.5 4.5 4.5 4.5 4.5 4.5 4.5 Permethrin 3.3 3.3 3.3 3.3 3.3 3.3 3.3 Alkyldimethylamine, where the alkyl group is 9.0 18.0 27.0 36.0 45.0 54.0 90.0 comprised (approximately) 95% C18 Co-solvent (e.g., glycol 20 20 20 20 20 20 20 ether) White spirit Balance Balance Balance Balance Balance Balance Balance

Example 12: Solvent-based wood preservativeformulations of]: I tebuconazole/propiconazole mixture, with and without tertiary amines In this example the activity of the azole combination, tebuconazole and propiconazole, was compared with that of formulations containing tebuconazole, propiconazole and various tertiary amines. The results are summarised in Table 9, below, showing the mean infection(%) of radiata pine sapwood specimens treated with solvent-based formulations of the 1:1 tebuconazole/propiconazole mixture, with and without tertiary amines, after two weeks incubation. The combination of tebuconazole and propiconazole performs moderately against the mould fungi, however when combined with a number of tertiary amines, the efficacy of the mixtures improves substantially. None of the tertiary amines reduced mould growth at any of the concentrations tested.

Mean infection (%) of radiatapine sapwood specimens treated with solvent-based formulations of the 1:1 tebuconazole/propiconazolemixture, with and without tertiary amines, after two weeks incubation. Table 9 Retention Retention Mean Infection Fungicide (% Tertiaryamine (% rn/m) (%)a

[Untreated 100 control]

[Solvent only] - - - 80

Tebuconazole, propiconazole 0.03 - - 60 (1:1, w:w)

Tebuconazole, Stearyl dimethylamine propiconazole 0.03 (98%) 0.09 <10 (1:1)

Tebuconazole, N-alkyl-N,N propiconazole 0.03 dimethylamine; Alkyl 0.09 <5 (1:1) =C14 -C 20 mixture

Tebuconazole, propiconazole 0.03 Lonzabac 12' 0.03 40 (1:1)

Tebuconazole, N-alkyl-N,N propiconazole 0.03 dimethylamine; Alkyl 0.09 30 (1:1) =C1 0-C 16 mixture

aAverage of four replicates. The tertiary amines showed no resistance to mould at the concentrations tested bAlkyl chain distribution: C20 < 1.5; C18 > 95%; C16, C14 <4.5%

'Lonzabac 12= bis(3-aminopropyl)dodecylamine dAlkyl chain distribution: C16 < 2%; C14 22-32%; C12 65-75%

Example 13: Wood preservativeformulations containing Cyproconazole with amines In Example 13, the ability of cyproconazole to prevent mould on the surface of treated timber specimens was evaluated both with and without the addition of a tertiary amine. The solvent-based formulations used to treat the specimens are described in Table 10. The untreated and solvent-treated controls were heavily infected after two weeks incubation in a mould chamber, as were the cyproconazole treated specimens. Cyproconazole alone offered very poor protection of the treated wood surface, whereas combining cyproconazole with stearyl dimethylamine in a 1 to about 23 ratio provided significant improvement in anti-fungal efficacy. The results are summarised in Table 11.

Cyproconazole and penflufen/amine formulations Table 10 Example Cyproconazole Penflufen -Igrden '1Cw/)Cyproconazole + amine Penflufen + amine

Cyproconazole concentrate 7.13 7.13 (0.75% w/w cyproconazole) (0.053% active) (0.053% active) 1.25 1.25 Penflufen concentrate - (0.027% (0.027% (2.16% w/w penflufen)- active) active) Stearyl dimethylamine (CAS - 1.21 - 0.81 124-28-7) Solvent (white spirit) Balance Balance Balance Balance

Surface infection of radiatapine sapwood specimens after incubation in a mould chamber Table ]]

Fungicide Retention Amine Retention Mean infection (% w/w) (% w/w) (%) Cyproconazole 0.004 - - 55

Cyproconazole 0.004 Stearyl dimethylamine 0.09 0

Penflufen 0.002 - - 60

Penflufen 0.002 Stearyl dimethylamine 0.06 20

Solvent control - - 60 Untreated 90 control

Example 14: Wood preservativeformulations containing Penflufen with amines Other fungicides with different modes of action, e.g., penflufen (a succinate dehydrogenase inhibitor), were also examined. In the case of penflufen, the fungicide to amine ratio was approximately 1 to 30. The solvent-based formulation is shown in Table 10, above. As shown, the performance of the fungicide improved substantially in the presence of the tertiary amine (see, Surface infection of radiata pine sapwood specimens after incubation in a mould chamber, in Table 11, above).

Example 15: Wood preservativeformulations containing copper naphthenate, didecyldimethyl ammonium chloride (DDAC) and 4,5-dichloro-2-octylisothiazol-3(2H)-one(DCOIT) In a further series of examples, solvent-based formulations of copper naphthenate, didecyldimethylammonium chloride (DDAC) and 4,5-dichloro-2 octylisothiazol-3(2H)-one (DCOIT) were prepared with and without stearyl dimethylamine as described in Table 12 and used to treat radiata pine specimens.

Copper naphthenate, didecyldimethylammonium chloride and 4,5-dichloro-2 octylisothiazol-3(2H)-one/tertiaryamineformulations Table 12 Example DDAC DDAC DCOIT DCOIT CuN + + + CuN +

+ DDAC amine amine DCOITamine amine Ingredient (% w/w) amine (1:1) (1:2) (1:1) (1:2) Copper naphthenate 9.0 9.0 - - - - (6% w/w Cu metal) Bardac 2280 (80% - - 2.0 2.0 2.0 - DDAC) DCOIT concentrate - - - - - 2.25 2.25 2.25 (30% w/w DCOIT) Stearyl dimethylamine - 1.6 - 1.61 3.22 - 0.68 1.35 Solvent (white spirit) Bal. Bal. Bal. Bal. Bal. Bal. Bal. Bal. Abbreviations: copper naphthenate = CuN; didecyldimethylammonium chloride = DDAC; DCOIT= 4,5-dichloro-2-octylisothiazol-3(2H)-one; Balance = Bal.

The treated specimens were exposed to mould fungi as described above, along with solvent-treated and untreated specimens. After approximately three weeks of incubation, the untreated and solvent-treated specimens were infested heavily with mould, having 80 and 100% of their respective surfaces covered with various mould fungi. The specimens treated with copper naphthenate only were infected equally (85% coverage), however those treated with the combination of copper naphthenate and stearyl dimethylamine (Cu:amine ratio w:w ~ 1:3) were relatively free of mould, with only on 10% of the surface infected. The specimens treated with solvent-based formulations of DDAC and DCOIT developed some mould (approximately 30% coverage), but considerably less than that of CuN. The improvement in performance upon combing the fungicide with the amine was still apparent, albeit less pronounced.

Example 16: Results of laboratorydecay test of azoles in combination with various amines in solvent-basedformulations Table 13 Treatment Mass loss(%)a Fungicide Fungiide Amine Fungicide/ mineamine ratio F. lilacino- P. placenta Pgplcent Untreated control - - 66.7 30.6 Solvent treated control - - 62.6 43.3 Tebuconazole / - - 20.3 3.8 propiconazole 0.03% m/m Tebuconazole / Stearyl dimethylamine (min. 1/3 6.7 1.0 propiconazole 0.03% m/m 95%) Tebuconazole/ N-alkyl-N,N dimethylamine; Alkyl 1/3 3.4 2.3 propiconazole 0.03%rn/rn1-C0mitr b = C1 -C 20 mixture

Tebuconazole / N-alkyl-N,N dimethylamine; Alkyl 1/3 12.4 1.5 propiconazole 0.03% m/m = C10-C1 6 mixture Cyproconazole 0.004% - 42.1 30.7 m/m

Cyproconazole 0.004% Stearyl Crom dimethylamine (min. 1/22.5 25.6 5.6 95%) aAverage of six replicates. The tertiary amines showed no resistance to decay at the concentrations tested. bAlkyl chain distribution: C20 < 1.5; C18 > 95%; C16, C14 <4.5%. cAlkyl chain distribution: C16 < 2%; C14 22-32%; C12 65-75%.

The formulations described in Examples 12-15 were also used to treat radiata pine sapwood specimens measuring 20 x 20 x 10 mm that were exposed to certain decay fungi in a series of laboratory soil block tests, which followed the procedures as described previously. The specimens were all leached and vacuum oven dried prior to sterilisation for the soil block test. The results of the laboratory bioassay are shown in Table 13, where the mass losses against two brown rot decay fungi Fomotopsis lilacino-gilva and Postiaplacenta are shown for the different preservative treatments. In each case the combination of an amine and a fungicide resulted in a decrease in mass loss (compared with the fungicide alone), implying a reduced amount of decay.

Example 17: Toxic thresholdforfungicide andfungicide/ amine combinations in solvent-based preservativeformulations In another series of tests, the toxic thresholds for various fungicides were determined in combination with an amine, and compared with the thresholds for the fungicides alone. All of the formulations were solvent-based. The results are summarised in Table 14. All of the mixtures of fungicide and tertiary amine are synergistic.

Toxic thresholdforfungicide andfungicide/ amine combinations in solvent-based preservativeformulations Table 14

Amine Toxic threshold Fungicide (% n/m) Didecyldimethylammonium 0.82a chloride Didecyldimethylammonium Stearyl dimethylamine 0.22a chloride (1:1 ratio with DDAC 4,5-dichloro-2-octylisothiazol- 0.15 3(2H)-one (DCOIT) 4,5-dichloro-2-octylisothiazol- Stearyl dimethylamine 0.12 3(2H)-one (1:1 ratio with DCOIT 4,5-dichloro-2-octylisothiazol- Stearyl dimethylamine 0.09 3(2H)-one (1:2 ratio with DCOIT aAgainst Fomotopsislilacino-gilva.

bAgainst Fomotopsispalustris.

Example 18: Example solvent-based work solutions Table 15, below, gives an example range of formulations that have proven to be stable and suitable for use as preservative work solutions. In each case the work solution contained 4.5 g/L of both tebuconazole and permethrin, as well as 3.3 g/L permethrin, dissolved in a glycol ether co-solvent. The different work solutions contained a variety of alkydimethylamines, at concentrations of 9, 27 and 90 g/L. Each of the work solutions was shown to be stable at ambient and low temperature.

Summary of solvent-based work solutions

Table 15 Active Amine Exxsol Formulation ingredients Amine Concentration D80 (g/L) (g/L)" 1 TPP (4.5, 4.5, 3.3) Lauryl 9.0 Balance dimethylamine 9.0 Balance 2 TPP (4.5, 4.5, 3.3) Lauryl 90.0 Balance dimethylamine 9.0 Balance 3 TPP (4.5, 4.5, 3.3) ylamin 90.0 Balance dimethylamine 4 TPP (4.5, 4.5, 3.3) Myristyl 2.0 Balance dimethylamine 9.0 Balance 5 TPP (4.5, 4.5, 3.3) Myristyl .0 Balance dimethylamine 27.0 Balance 6 TPP (4.5, 4.5, 3.3) yamine 90.0 Balance dimethylamnine 7 TPP (4.5, 4.5, 3.3) Cetyl in g tle dimethylaExine 8 TPP (4.5, 4.5, 3.3) Cetyl 2. aac dimethylaine 27.0 ace 9 TPP (4.5, 4.5, 3.3) Cetyl 9. aac dimethylamnine 9. aac 10 TPP (4.5, 4.5, 3.3) Stearyl9. Banc dimethyamine 9.0 Balane 11I TPP (4.5, 4.5, 3.3) Stearyl 2. aac dimethyamine 2. aac 12 TPP (4.5, 4.5, 3.3) Stearyl 9. aac __________ ____________I 9. dimethyamnine aac 0 TPP tebuconazole, propiconazole &permethrin, dissolved in aglycol ether co -solvent.

Example 19: Wood preservativeformulationstested againstMastotermesdarwiniensis In the process of investigating the effects of tertiary amines on the activity of various fungicides in solvent-based preservatives, it was found that tertiary amines also enhanced the insecticidal activity of a synthetic pyrethroid, permethrin. Radiata pine sapwood specimens measuring 200 x 35 x 35 mm were treated with a solvent-based formulation containing the fungicides tebuconazole and propiconazole, and the insecticide permethrin. The formulation also contained the tertiary amine stearyl dimethylamine. The ratio of azole to tertiary amine ratio was 1:3. Typically solvent-based preservatives contain sufficient permethrin to achieve a retention of 0.02% m/m in the treated timber. This retention of permethrin protects timber from destruction by the subterranean termite, Mastotermes darwiniensis. In the test described herein, a lower permethrin retention was chosen (0.005% m/m) in order to observe if the presence of the tertiary amine had a positive effect on the performance of the treated article against subterranean termites. Specimens were also treated with what is termed a reference preservative, which contained only the fungicides tebuconazole and propiconazole, and the insecticide permethrin. Solvent treated controls and untreated controls were also included in the test. An outdoor, above-ground field test was carried out in accordance with the Protocolsfor the Assessment of Wood Preservatives,AustralasianWood Preservation Committee (March 2007 Revision, Ensis, Clayton), which is hereby incorporated by reference in its entirerty. The specimens were exposed in the Northern Territory to M. darwinensisfor a period of six months, after which they were returned to the laboratory, cleaned and oven dried. The mass loss of each specimen was determined, and the mean mass loss for a given treatment calculated. The results are shown in Figure 3. The untreated and solvent-treated controls were effectively destroyed, with mass loss > 95%. The specimens treated with the reference preservative that contained only tebuconazole, propiconazole and permethrin (at 0.005%m/m) suffered substantial attack, with a mean mass loss of 57%. In contrast, the preservative-treated specimens that additionally contained the tertiary amine stearyl dimethylamine suffered significantly lower mass loss (14%).

Examples 20-22: Furtherbenefits of tertiary amine additivesfor solvent-based wood preservative formulations The tertiary amine stearyl dimethylamine reduces the propensity of the treated timber specimens to swell when submerged in water. This is somewhat surprising, in view of what is known about how traditional light organic solvent preservative (LOSP) water repellents additives function.

Radiata pine sapwood (90 x 35 mm in cross-section) was treated with white spirit preservative formulations containing 1:3, 1:6 and 1:10 ratios of azole (tebuconazole, propiconazole) to stearyl dimethylamine (refer to Table 16, below). These formulations did not contain any additional water repellent components. A matched set of specimens were also treated with a typical water repellent-containing formulation for comparative purposes.

Table 16

RawMaterial Example 20 Example 21 Example 22 Coexamptive (g/L) (g/L) (g/L) (g/L) Tebuconazole 4.5 4.5 4.5 4.5 Propiconazole 4.5 4.5 4.5 4.5 Permethrin 3.3 3.3 3.3 3.3 Alkyldimethylamine, where the alkyl group is comprised 27 54 90 (approximately) of 95% C18 Co-solvent (e.g., glycol 20 20 20 20 ether) Water repellent pack - - - 34 White spirit Balance Balance Balance Balance

After treatment and evaporation of the solvent, the wafers (7 mm thick) were conditioned at 25 C / 60% RH for three days. The dimensional stability was evaluated by determining the swelling (% swelling) upon immersion of the wafer in water, using a procedure adapted from the American Wood Protection Association (AWPA) Standard E13-09, Standardmethod of testing to determine the water repellency ofpressure-treatedlumber. The swelling was determined after 5 and 30 minutes of immersion time. The results are shown in Table 17.

Table 17 %Swelling %Swelling Formulation (5 min.) (30 min.) Untreated control 1.81 3.29 Comparative example, containing water repellent 0.38 1.87 Example 20, azole/stearyl dimethylamine 1:3 0.48 1.70 Example 21, azole/stearyl dimethylamine 1:6 0.28 1.22 Example 22, azole/stearyl dimethylamine 1:10 0.28 1.11

After 5 minutes immersion the swelling observed for specimens treated with the tertiary amine formulations was similar to that for the comparative example. However, after 30 minutes immersion the differences become more pronounced and the specimens treated with the tertiary amine containing formulations all swell less than those treated with the formulation containing the water-repellent. Although the invention has been described with reference to specific examples it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.

Claims (23)

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A wood preservative formulation comprising: a non-aqueous carrier; one or more preservative compounds; and one or more tertiary amine compounds as a potentiator of the one or more preservative compounds.

2. A formulation according to claim 1, wherein the one or more preservative compounds and the one or more tertiary amine compounds are present in synergistic amounts.

3. A formulation according to claim 1 or claim 2, wherein the one or more tertiary amine compounds are selected from the group consisting of monoalkylamines, dialkylamines and triaklylamines.

4. A formulation according to any one of claims 1 to 3, wherein the one or more tertiary amine compounds comprise methyl or ethyl substituents and/or alkyl substituents which may be either linear or branched, with, on average, a minimum of 8 carbons.

5. A formulation according to any one of claims 1 to 3, wherein the one or more tertiary amine compound comprise an alkyldimethylamine of the general formula RN(Me) 2, wherein R is a linear or branched carbon chain, with an average chain length between 8-22 carbons per molecule.

6. A formulation according to any one of claims 1 to 3, wherein the one or more tertiary amine compounds comprise a dialkylmethylamine of the general formula MeN(R) 2, wherein R is a linear or branched carbon chain, with an average chain length between 8-22 carbons per molecule.

7. A formulation according to any one of claims 1 to 3, wherein the one or more tertiary amine compounds comprise a trialkylamine of the general formula

NR 3, wherein R is a linear or branched carbon chain, with an average chain length between 8-22 carbons per molecule.

8. A formulation according to any one of claims 1 to 7, wherein the one or more tertiary amine compounds comprise a mixture of different alkyl chain lengths.

9. A formulation according to any one of claims 1 to 3, wherein the one or more tertiary amine compounds comprise N-(3-aminopropyl)-N-dodecylpropane 1,3-diamine.

10. A formulation according to any one of claims 1 to 9, wherien the one or more preservative compounds is selected from the group consisting of: insecticides, termiticides, fungicides, mouldicides, and mixtures thereof.

11. A formulation according to any one of claims 1 to 10, wherein the one or more preservative compounds comprise an insecticide.

12. A formulation according to any one of claims 1 to 11, wherein the one or more preservative compounds are selected from isothiazolinones, succinate dehydrogenase inhibitor (SDHI) compounds, phenols, metal-based compounds, quaternary ammonium compounds, triazole compounds, synthetic pyrethroids, and mixtures thereof.

13. A formulation according to any one of claims 1 to 12, wherein the one or more preservative compounds comprise a triazole compound of formulae (I) or (II): OH _O R R2-CH 2 -CH 2 R1

CH 2 0 OH2

N N

N / (I) N / wherein R 1 represents a branched or straight chain C1_5 alkyl group; R 2 represents a phenyl group optionally substituted by one or more substituents selected from halogen, C 1_ 3alkyl, C 1 _3 alkoxy, phenyl and nitro; R 3 is as defined for R 2 ; and R 4 represents a hydrogen atom or a branched or straight chain C 15 alkyl.

14. A formulation according to any one of claims 1 to 13, wherein the one or more preservative compounds comprise a fungicide selected from azaconazole, tebuconazole, propiconazole, cyproconazole, hexaconazole, triadamefon, 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT), didecyldimethylammonium chloride, didecyldimethylammonium carbonate/bicarbonate, benzalkonum chloride, penflufen, 3-iodo-2-propynyl butylcarbamate (IPBC), copper naphthenate, copper oxine, copper octanoate, copper soaps, zinc naphthenate, zinc octanoate, zinc soaps, tributyltin naphthenate, chlorothalonil, pentachlorophenol.

15. A formulation according to any one of claims 1 to 14, wherein the one or more preservative compounds comprise permethrin.

16. A formulation according to any one of claims 1 to 15, wherein the weight ratio of the preservative to potentiator is about 100:1 to about 1:100.

17. A formulation according to any one of claims 1 to 16, wherein the weight ratio of the preservative to potentiator is about 1:1 to about 1:3.

18. A formulation according to any one of claims 1 to 17, wherein the non aqueous carrier is selected from the group consisting of: white spirit, kerosene, low aromatic solvents and mixtures thereof.

19. A formulation according to any one of claims 1 to 18, wherein the non aqueous carrier comprises a solvent mixture, itself comprising water combined with a hydrocarbon fraction.

20. A method of treating a substrate of wood or other cellulosic material by applying to the substrate a preservative formulation as defined according to any one of claims 1 to 19.

21. Treated wood, when so-treated by a method defined according to claim 20.

22. Treated wood according to claim 21, wherein the treated wood comprises wood composites selected from the group consisting of: particle board, medium density fibreboard (MDF), oriented strand board (OSB), plywood, laminated veneer lumber (LVL), glue laminated lumber or cross laminated lumber.

23. A method of preparing a wood preservative formulation as defined according to any one of claims 1 to 19, the method comprising the steps of admixing: a non-aqueous carrier; one or more preservative compounds; and one or more tertiary amine compounds.