Controlled release, wood preserving composition for treating in-service utility poles, posts, pilings, cross-ties and other wooden structures

Abstract

Disclosed herein are compositions comprising a dispersion of solid particles of a substantially insoluble copper compound; a boron-containing compound, a fluoride-containing compound, or a combination thereof; wherein at least 20% of the particles of the composition comprise particles having particle size greater than 25 microns. Also disclosed herein are methods of making and using the same.

Claims

1. A composition comprising: a dispersion of solid particles of a substantially insoluble copper compound; a boron-containing compound, a fluoride-containing compound, or a combination thereof; and wherein at least 20% of the particles of the composition comprise particles having particle size greater than 25 microns.

2. The composition of claim 1, wherein the dispersion of solid particles of the substantially insoluble copper compound is in an amount from 0.001% to 10% by weight of the composition.

3. The composition of claim 1, wherein less than 20% of the particles of the composition comprise particles having particle size greater than 100 microns.

4. The composition of claim 1, wherein the composition contains from 1% to 5% copper atoms by weight of the composition.

5. The composition of claim 1, wherein the copper compound comprises copper hydroxide, cupric oxide, cuprous oxide, copper carbonate, basic copper carbonate, copper oxychloride, copper dimethyldithiocarbamate, copper omadine, copper borate, or a combination thereof.

6. The composition of claim 1, wherein the boron-containing compound comprises a boric acid, a metal borate, a sodium borate, a potassium borate, or a combination thereof.

7. A method for remedial treatment of wood, comprising applying the composition of claim 1 to a wooden structure.

8. The method of claim 7, wherein the wooden structure is an in-service wood product.

9. The method of claim 7, wherein the composition is applied onto or into the wooden structure.

10. The method of claim 8, wherein the in-service wood product is a utility pole, a railroad tie, or a wooden bridge.

11. A method comprising blending particles of a substantially insoluble copper compound; and a boron-containing compound, a fluoride-containing compound, or a combination thereof; to produce a composition, wherein at least 20% of the particles of the composition comprise particles having particle size greater than 25 microns.

12. The method of claim 11, wherein at least 30% of the particles of the composition comprise particles having particle size greater than 25 microns.

13. The method of claim 11, wherein the composition contains from 1% to 5% copper atoms by weight of the composition.

14. The method of claim 11, wherein the copper compound comprises copper hydroxide, cupric oxide, cuprous oxide, copper carbonate, basic copper carbonate, copper oxychloride, copper dimethyldithiocarbamate, copper omadine, copper borate, or a combination thereof.

15. The method of claim 11, wherein the boron-containing compound comprises a boric acid, a metal borate, a sodium borate, a potassium borate, or a combination thereof.

16. A method of delivering a fungitoxic amount of copper ion to an interior portion of a wooden product comprising: applying a composition comprising a dispersion of solid particles of a substantially insoluble copper compound; and a boron-containing compound, a fluoride-containing compound, or a combination thereof; wherein at least 20% of the particles of the composition comprise particles having particle size greater than 25 microns; and wherein applying the composition to the wooden structure produces penetration of copper ions into an interior portion of the wooden structure to a fungicidally effective level.

17. The method of claim 16, wherein at least 30% of the particles of the composition comprise particles having particle size greater than 25 microns.

18. The method of claim 16, wherein the composition contains from 1% to 5% copper atoms by weight of the composition.

19. The method of claim 16, wherein the copper compound comprises copper hydroxide, cupric oxide, cuprous oxide, copper carbonate, basic copper carbonate, copper oxychloride, copper dimethyldithiocarbamate, copper omadine, copper borate, or a combination thereof.

20. The method of claim 16, wherein the boron-containing compound comprises a boric acid, a metal borate, a sodium borate, a potassium borate, or a combination thereof.

Description

DETAILED DESCRIPTION

(1) Unless stated otherwise, such as in the examples, all amounts and numbers used in this specification are intended to be interpreted as modified by the term about. Likewise, all elements or compounds identified in this specification, unless stated otherwise, are intended to be non-limiting and representative of other elements or compounds generally considered by those skilled in the art as being within the same family of elements or compounds.

(2) As used herein, the term micronized means a particle size in the range of 0.001 to 25 microns. As used herein, the term particle size means the largest axis of the particle, and in the case of a generally spherical particle, the largest axis is the diameter. Furthermore, it should be understood that micronized does not refer only to particles which have been produced by the finely dividing, such as by mechanical grinding, of materials which are in bulk or other form. Micronized particles can also be formed by other mechanical, chemical or physical methods, such as, for example, formation in solution, with or without a seeding agent, grinding or impinging jet. The micronized copper particles disclosed in U.S. Patent Application Publication No. 2005/0118280 are hereby specifically incorporated by reference, in their entirety.

(3) As used herein, copper-solubilizing agents mean any agent that promotes the solubility of copper metal or a copper compound in an aqueous carrier. Copper-solubilizing agents include, but are not limited to ammonia and ammonium salts, amines, and alkanolmonoamines having between 2 to 18 carbon atoms, such as monoalkanolmonoamines, dialkanolmonoamines, and trialkanolmonoamines, and mixtures thereof. Examples include monoethanolamine, diethanolamine, triethanolamine, 3-aminopropanol, monoisopropanolamine, 4-aminobutanol, monomethylethanolamine, dimethylethanolamine, triethylethanolamine, monoethylethanolamine, N-methyldiethanolamine and mixtures thereof.

(4) Disclosed herein is a supplemental/remedial composition for wood and a method for use thereof in treatment of in-service wooden products, more particularly utility poles, railroad ties, wooden bridges. The composition comprises copper with a boron compound or fluoride compound. The composition imparts to the treated wood resistance to both fungi and insects. The composition can additionally comprise an organic fungicide/termiticide.

(5) In an effort to limit the level of volatile organic compounds (VOCs) being released into the atmosphere and to minimize worker exposure, the Environmental Protection Agency (EPA) published the architectural coatings rule on 1988 under authority of the Clean Air Act. The purpose of this rulemaking was to reduce the VOCs emitted from architectural and industrial maintenance coatings thus limiting the amount of VOCs that manufacturers can put in their products. Remedial preservative paste formulations are defined by EPA as architectural coatings and below ground wood preservatives. The VOC limit established by EPA for below ground wood preservatives is 550 grams of VOC per liter of coating. Individual States such as Pennsylvania, New York and California (South Coast Air Quality Management District) have established a more stringent allowable VOC limit for below ground wood preservatives of 350 grams per liter of coating. The present invention provides compositions containing no more than 36, 30, 20, 10, 5, 2 or 1 grams volatile organic compounds (VOCs) per liter of the composition. In a preferred embodiment, VOCs are not detectable by gas chromatography/mass spectrometry (GC/MS). In another preferred embodiment, VOCs are not detectable by gas chromatography according to EPA Method 8620, Volatile Organic Compounds by Gas Chromatography Mass Spectrometry (GC/MS), which is incorporated herein by reference in its entirety.

(6) The compositions of the present invention have a broad spectrum of bio-efficacy against wood decay fungi, including, brown rot fungi, white rot fungi, and soft rot fungi. Non-limiting examples of brown rot fungi include: Coniophora puteana, Serpula lacrymans, Antrodia vaillantii, Gloeophyllum trabeum, Gleoeophyllum sepiarium, Lentinum lepideus, Oligoporus placenta, Meruliporia incrassate, Daedalea quercina, Postia placenta. Non-limiting examples of white rot fungi include: Trametes versicolor, Phanerochaete chrysosporium, Pleurotus ostreatus, Schizophyllum commune, Irpex lacteus. Some non-limited examples of soft rot fungi are Chaetomium globosum, Lecythophora hoffmannii, Monodictys putredinis, Humicola alopallonella, Cephalosporium, Acremonium, and Chaetomium.

(7) The compositions of the present invention are also effective against a broad range of insects and marine borer, including termites, beetles, and wood-boring insects. Non-limiting examples of termites include drywood termites such as Cryptotermes and Kaloterms, and dampwood termites such as Zootermopsis, subterranean termites such as Coptotermes, Mastotermes, Reticulitermes, Schedorhinotermes, Microcerotermes, Microtermes, and Nasutitermes. Non-limiting examples of beetles include those in families such as, for example, Anoniidae, Bostrychidae, Cerambycidae, Scolytidae, Curculionidae, Lymexylonidae, and Buprestidae.

(8) The compositions of the present invention can be formulated into a waterborne paste- or grease-type of formulation, if desired, such that the formulation has an adhesive nature and is easy to apply to a desired location.

(9) The present invention includes copper. The preferred form of copper for preparation of the aqueous paste compositions of the present invention is a fine particulate, such that is found in dispersions through a milling process or the like. Methods for preparing milled substantially insoluble biocidal particulates that can be used in aqueous wood preservative compositions that can be applied to a wood product by vacuum and/or pressure treatment to effectively penetrate and preserve wood may be found in U.S. Patent Application Publication Nos. 2004/0258767, 2005/0118280 and 2006/0288904 to Leach and Zhang. The weight ratio of copper in the composition varies from about 0.001% to about 10% by weight. The preferred range of weight ratio of copper in the composition varies from about 0.1% to about 1% by weight.

(10) The present invention also comprises a boron compound, a fluoride compound or both. The boron compound can be either water soluble or water insoluble. Non-limiting examples of water soluble boron compounds include boric acid, sodium borates, such as sodium tetraborate decahydrate, sodium tetraborate pentahydrate, and disodium octaborate tetrahydrate (DOT) and potassium borates. Non-limiting examples of water insoluble boron compounds include metal borate compounds such as calcium borate, borate silicate, aluminum silicate borate hydroxide, silicate borate hydroxide fluoride, hydroxide silicate borate, sodium silicate borate, calcium silicate borate, aluminum borate, boron oxide, magnesium borate, iron borate, copper borate and zinc borate.

(11) Preferred boron compounds are water soluble boron compounds, such as boric acid and sodium tetraborate decahydrate, sodium tetraborate pentahydrate and disodium octaborate tetrahydrate (DOT).

(12) The weight ratio of boron compound to copper can be in the range of from about 1:1 to about 500:1, the preferred weight ratio range is about 10:1 to about 200:1.

(13) The present invention can also include a fluoride compound. Non-limiting examples of fluoride compounds include sodium fluoride, potassium fluoride, calcium fluoride, copper fluoride, iron fluoride, magnesium fluoride, and other metal compounds of fluoride. The preferred fluorides are sodium fluoride and potassium fluoride. The weight ratio of fluoride compound to copper can be in the range of from about 1:1 to about 1000:1, the preferred weight ratio range is about 10:1 to about 200:1.

(14) The present composition optionally comprises one or more combinations of a organic biocides, such as quaternary ammonium compounds, triazole or imidazole compounds, isothiazolone compounds, pyrethroid compounds and other biocides such as imidacloprid; fipronil; cyfluthrin; bifenthrin; permethrin; cypermethrin; and chlorpyrifos, iodopropynyl butylcarbamate (IPBC); chlorothalonil; 2-(thiocyanatomethylthio) benzothiazole; alkoxylated diamines and carbendazim. When the organic biocide is used in the composition, the weight ratio of the organic biocide in the composition is generally in the range of from 0.001% to 10% by weight, with a preferred range of 0.005% to 5% by weight and a more preferred range of 0.01% to 1%.

(15) Each of the organic biocides listed in Tables 1-4 of U.S. Patent Application Publication No. 2005/0118280 are hereby specifically incorporated by reference, in their entirety.

(16) Non-limiting examples of quaternary ammonium compounds are: didecyldimethylammonium chloride; didecyldimethylammonium carbonate/bicarbonate; alkyldimethylbenzylammonium chloride; alkyldimethylbenzylammonium carbonate/bicarbonate; didodecyldimethylammonium chloride; didodecyldimethylammonium carbonate/bicarbonate; didodecyldimethylammonium propionate; N,N-didecyl-N-methyl-poly(oxyethyl)ammonium propionate.

(17) Non-limiting examples of triazole or imidazole compounds are: 14[242,4-dichlorophenyl)-1,3-dioxolan-2-yl]methyl]-1H-1,2,4-triazole (azaconazole), 1-R2RS,4RS:2RS, 4SR)-4-bromo-2-(2,4-dichlorophenyptetrahydrofurfuryl]-1H-1,2,4-triazole (bromuconazole), 2RS,3RS;2RS,3SR)-2-(4-chlorophenyl)-3-cyclopropyl-1-(1H-1,2,4-triazol-1-yl)butan-2-ol (Cyproconazole), (2RS,3RS)-1-(2,4-dichlorophenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl) pentan-3-ol (diclobutrazol), cis-trans-3-chloro-444-methyl-2-(1H-1,2,4-triazol-1-ylmethyl)-1,3-dioxolan-2-yliphenyl 4-chlorophenyl ether (difenoconazole), (E)-(R5)-1-(2,4-dichlorophenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)pent-1-en-3-ol (diniconazole), (E)--1-(2,4-dichlorophenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)pent-1-en-3-ol (diniconazole-M), (2RS, 3SR)-143-(2-chlorophenyl)-2,3-epoxy-2-(4-fluorophenyl)propyl]-1H-1,2,4-triazole (epoxyconazole), (RS)-142-(2,4-dichlorophenyl)-4-ethyl-1,3-dioxolan-2-ylmethyli-1H-1,2,4-triazole (etaconazole), (RS)-4-(4-chlorophenyl)-2-phenyl-2-(1H-1,2,4-triazol-1-ylmethyl)butyronitrile (fenbuconazole), 3-(2,4-dichlorophenyl)-6-fluoro-2-(1H-1,2,4-triazol-1-yl)quinazolin-4(311)-one (fluquinconazole), bis(4-fluorophenyl)(methyl)(1H-1,2,4-triazol-1-ylmethyl)silane (flusilazole), (RS)-2,4-difluoro-a-(1H-1,2,4-triazol-1-ylmethyl)benzhydryl alcohol (flutriafol), (2RS, 5RS; 2RS,5SR)-5-(2,4-dichlorophenyl)20arboxymeto-5-(1H-1,2,4-triazol-1-ylmethyl)-2-furyl 2,2,2-trifluoroethyl ether (furconazole), (2RS,5RS)-5-(2,4-dichlorophenyptetrahydro-541H-1,2,4-triazol-1-ylmethyl)-2-furyl 2,2,2-trifluoroethyl ether(furconazole-cis), (RS)-2-(2,4-dichloro-phenyl)-1-(1H-1,2,4-triazol-1-yl)hexan-2-ol(hexaconazole), 4-chlorobenzyl (EZ)-N-(2,4-dichlorophenyl)-2-(1H-1,2,4-triazol-1-yl)thioacetamidate (imibenconazole), (1RS,2SR,5RS; 1RS,2SR,5SR)-2-(4-chlorobenzyl)-5-isopropyl-1-(1H-1,2,4-triazol-1-ylmethyl)cyclopentanol (ipconazole), (1RS,5RS; 1RS,5SR)-5-(4-chlorobenzyl)-2,2-dimethyl-1-(1H-1,2,4-triazol-1-ylmethyl)cyclopentanol (metconazole), (RS)-2-(4-chlorophenyl)-241H-1,2,4-triazol-1-ylmethyl)hexanenitrile (myclobutanil), (RS)-1-(2,4-dichloro-(3-propylphenethyl)-1H-1,2,4-triazole(penconazole), cis-trans-1-[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl methyl]-1H-1,2,4-triazole (propiconazole), (RS)-2-[2-(1-chlorocyclopropyl)-3-(2-chlorophenyl)-2-hydroxypropyl1-2,4-dihydro-1,2,4-triazole-3-thione(prothioconazole), 3-(2,4-dichlorophenyl)-2-(1H-1,2,4-triazol-1-yl)-quinazolin-4(311)-one (quinconazole), (RS)-2-(4-fluoro-phenyl)-1-(1H-1,2,4-triazol-1-yl)-3-(trimethylsilyl)propan-2-ol (simeconazole), (RS)-1-p-chlorophenyl-4,4-dimethyl-3-(1H-1,2,4-triazol-1-ylmethyl)pentan-3-ol (tebuconazole), propiconazole, (RS)-2-(2,4-dichlorophenyl)-3-(1H-1,2,4-triazol-1-yl)propyl 1,1,2,2-tetrafluoroethyl ether (tetracon-azole), (RS)-1-(4-chlorophenoxy)-3,3-dimethyl-1-(1H-1,2,4-triazol-1-yl)butan-2-one (triadime-fon), (1RS,2RS; 1RS,2SR)-1-(4-chlorophenoxy)-3,3-dimethyl-1-(1H-1,2,4-triazol-1-yl) butan-2-ol (triadimenol), (RS)-(E)-5-(4-chlorobenzylidene)-2,2-dimethyl-1-(1H-1,2,4-triazol-1-ylmethyl)cyclopentanol (triticonazole), (E)-(RS)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1H-1,2,4-triazol-1-yl)pent-1-en-3-ol (uniconazole), (E)-(S)-1-(4-chlorophenyl)-4,4-dimethyl-241H-1,2,4-triazol-1-yl)pent-1-en-3-ol (uniconazole-P), and 2-(2,4-difluorophenyl)-1-(1H-1,2,4-triazole-1-yl)-3-trimethylsilyl-2-propanol. Other azole compounds include: amisulbrom, bitertanol, fluotrimazole, triazbutil, climbazole, clotrimazole, imazalil, oxpoconazole, prochloraz, triflumizole, azaconazole, simeconazole, and hexaconazole.

(18) Non-limiting examples of isothiazolone compounds are: methylisothiazolinone; 5-chloro2-methyl-4-isothiazoline-3-one, 2-methyl-4-isothiazoline-3-one, 2-n-octyl-4-isothiazoline-3-one, 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one, 2-ethyl-4-isothiazoline-3-one, 4,5-dichloro-2-cyclohexyl-4-isothiazoline-3-one, 5-chloro-2-ethyl-4-isothiazoline-3-one, 2-octyl-3-isothiazolone, 5-chloro-2-t-octyl-4-isothiazoline-3-one, 1,2-benzisothiazoline-3-one, preferably 5-chloro-2-methyl-4-isothiazoline-3-one, 2-methyl-4-isothiazoline-3-one, 2-n-octyl-4-isothiazoline-3-one, 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one, 1,2-benzisothiazoline-3-one, etc., more preferably 5-chloro-2-methyl-4-isothiazoline-3-one, 2-n-octyl-4-isothiazoline-3-one, 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one, 1,2-benzisothiazoline-3-one, chloromethylisothiazolinone; 4,5-Dichloro-2-n-octyl-3(2H)-isothiazolone; 1,2-benzisothiazolin3-one.

(19) Non-limiting examples of pyrethroid compounds include acrinathrin, allethrin, bioallethrin, barthrin, bifenthrin, bioethanomethrin, cyclethrin, cycloprothrin, cyfluthrin, betacyfluthrin, cyhalothrin, gamma-cyhalothrin, lambda-cyhalothrin, cypermethrin, alphacypermethrin, beta-cypermethrin, theta-cypermethrin, zeta-cypermethrin, cyphenothrin, deltamethrin, dimefluthrin, dimethrin, empenthrin, fenfluthrin, fenpirithrin, fenpropathrin, fenvalerate, esfenvalerate, flucythrinate, fluvalinate, tau-fluvalinate, furethrin, imiprothrin, metofluthrin, permethrin, biopermethrin, transpermethrin, phenothrin, prallethrin, profluthrin, pyresmethrin, resmethrin, bioresmethrin, cismethrin, tefluthrin, terallethrin, tetramethrin, tralomethrin, transfluthrin, etofenprox, flufenprox, halfenprox, protrifenbute, silafluofen.

(20) Preferred organic biocides are tebuconazole and bifenthrin.

(21) The present invention also optionally comprises an aqueous type thickening agent. Aqueous organic polymer, aqueous emulsion, clay minerals, phosphate and the like are the aqueous type of thickening agents. Typical examples of aqueous organic polymers are cellulose derivatives including cellulose esters and ethers. Examples of cellulose esters are cellulose nitrate, sulfate, cellulose phosphate, cellulose nitrite, cellulose xanthate, cellulose acetate, cellulose formate, and cellulose esters with other organic acids. Examples of cellulose ethers are methylcellulose, ethylcellulose, propylcellulose, benzylcellulose, carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxybutylcellulose, cyanoethylcellulose, and 21 arboxymethylcellulose. The preferred cellulose derivatives are cellulose ethers such as hydroxyethylcellulose, hydroxypropylcellulose, carboxymethylcellulose and carboxyethylcellulose. The weight percentage of the cellulose derivative in the paste formulation is generally in the range of from about 0.01% to 50% with a preferred weight percentage of 0.1% to 20% and a more preferred weight percentage of 0.5% to 10%.

(22) Furthermore, the present invention also optionally comprises about 0.5% to about 30% of an inorganic clay thickening agent, or a mixture of such thickening agents. The inorganic clay thickening agents include a fibrous structure type such as attapulgite clay and sepiolite clay, a non-crystal structure type such as allophone, and mixed layer structure type such as montmorillonite and kaolinite and the above layer structure types. Examples of inorganic clay minerals, but not limited to, are: attapulgite, dickite, saponite, montmorillonite, nacrite, kaolinite, anorthite, halloysite, metahalloysite, chrysotile, lizardite, serpentine, antigorite, beidellite, stevensite, hectonite, smecnite, nacrite and sepiolite, montmorillonite, sauconite, stevensite, nontronite, saponite, hectorite, vermiculite, smecnite, sepiolite, nacrite, illite, sericite, glauconite-montmorillonite, roselite-montmorillonite, Bentone 38 (hectorite) and Bentone 34 (bentonite), chlorite-vermiculite, illite-montmorillonite, halloysite-montmorillonite, kaolinitemontmorillonite. The clay minerals employed in the compositions of the present invention also contain exchangeable cations including, but not limited to, aluminum ions, protons, sodium ions, potassium ions, calcium ions, magnesium ions, lithium ions, and the like.

(23) Among the above inorganic clay minerals, attapulgite, hectorite, bentonite, montmorillonite, sauconite, smecnite, stevensite, beidellite, nontronite, saponite, hectorite, vermiculite, nacrite, and sepiolite are particularly preferable for the present invention.

(24) Further, these inorganic clay minerals show a good thickening effect and thixotopic property in comparison with other aqueous thickening agents. Therefore, they show a little sagging and also they are very easy to be rinsed out by water in comparison with organic thickening agents.

(25) It should be appreciated that thickening agents other than described herein can be used.

(26) Optionally, the present invention also includes chemical additives that retard the drying of the paste composition. These are usually a blend of several glycols, such as ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol and their derivatives. By evaporating far more slowly than water, glycols or their derivatives can slow down the drying process of the paste composition. Humectants, such as glycerin and glycerol that absorb or hold water can also be added to retard or slow drying.

(27) The preservative paste compositions of this invention can be applied by various processes of supplemental or remedial treatment or protection of in-service wooden structures. The compositions of this invention are suitable for incorporation into wraps or ready-to-use bandages, injection into voids or cavities by pressure or by gravity and solid rods or cartridges.

(28) The paste compositions of this invention can be easily incorporated into a suitable support material to form a ready-to-use bandage or wrap that can applied to in-service utility poles and other wooden structures. Numerous support materials have been identified in literature and may include polymer films, fabrics, fiberglass, polyester fiber, polypropylene, porous polymer compositions and others that allow for the transfer or diffusion of preservative chemical from the bandage to the wood substrate. The paste composition may be applied to the support material by toweling, rolling, brushing and the like. The paste composition can be directly applied to the support material or may require the use of a binder or resin such as for example acrylate resins or PVC with plasticizers. To improve the adhesion between the paste compositions and support material the combination may be air-dried or dried in an oven at elevated temperatures.

(29) The paste compositions of this invention may also be formed into solid rods by extrusion, rolling or pressing. Once sufficiently dried, the rods can be cut to length and inserted into predrilled holes in in-service utility poles or other wooden structures. As with the bandages or wraps, resins or binders may be added to improve the dimensional stability of the rods.

(30) The paste compositions of this invention may be injected into internal voids or cavities through predrilled holes into in-service poles, posts, piling, cross-ties and other wooden structures by pressure processes or by gravity feed.

(31) The following examples are provided to further describe certain embodiments of the invention, their preparation and application as remedial or supplemental paste preserving system, but are in no way meant to limit the scope of the invention. For the experiments, penetration testing has been found to be an effective means of establishing the consistency and shear stability of compositions of this invention. Penetrometers are generally used for consistency tests on a wide range of food products, cosmetics, greases, pastes and other solid to semisolid products. Penetrometers utilize a standard cone or needle that is released from the Penetrometer and allowed to drop freely into the sample for 5 seconds at constant temperature. The depth of penetration of the cone into the sample is measured in tenths of a millimeter (tmm) by the Penetrometer. It has been establish through testing that the preferable penetration of the compositions of this invention range from about 125 to 425 tmm when using a standard Penetrometer equipped with a 102.5 gram brass cone with a stainless steel tip. A more preferable range of consistency for the present invention is about 175 to 375 tmm and a consistency or shear stability of about 200 to 300 tmm is particularly preferable for the present invention.

(32) The preferred viscosities of the thixotropic compositions of the present invention, during manufacture, is between 275 and 425 tenths of a millimeter (tmm) viscosity as measured using a penetrometer. More preferably the viscosities of the compositions of the present invention is between 300 and 400 tmm. Most preferably the viscosities of the compositions of the present invention is between 320 and 340 tmm.

(33) The preferred viscosities of the thixotropic compositions of the present invention is between 175 and 375 tenths of a millimeter (tmm) viscosity as measured using a penetrometer. More preferably the viscosities of the compositions of the present invention is between 200 and 300 tmm. Most preferably the viscosities of the compositions of the present invention is between 210 and 250 tmm.

(34) For determination of acceptability of viscosity, spreadability and adherence, compositions of the present invention can be rolled, troweled or brushed on wooden objects or more preferably to in-service utility poles, cross-ties or other wooden structures. Desirable compositions of the present invention should be self-supporting, have good spreadability such that the composition can be easily applied with a roller, trowel or brush without running or slumping off the wooden substrate or application tool and will easily adhere to a wooden substrate.

EXAMPLES

(35) The Examples listed below illustrate methods for preparing various compositions and treating wood according to the invention. These Examples below, illustrate methods for preparing alternative versions of the inventive compositions. The methods described in these Examples are illustrative only, and are not intended to limit the invention in any manner and should not be construed to limit the scope of claims herein.

Example 1

(36) A supplemental/remedial preservative paste composition was prepared by blending together in the order listed; 41.60 parts water, 6.00 parts of a fine copper dispersion comprised of 33.3% copper carbonate, 0.50 parts of a commercially available cellulose ether thickener, 43.70 parts sodium tetraborate decahydrate, and 8.20 parts attapulgite clay thickener. This remedial preservative paste contained 2.00 parts copper as derived from the fine copper carbonate dispersion for a weight ratio of 21.90 parts boron compound to 1.00 part copper.

(37) The supplemental/remedial preservative paste composition formulated according to the above example was applied to a wooden substrate using a trowel and was found to have desirable physical properties including viscosity, spreadability and adherence for application to in-service utility poles, cross-ties and other wooden structures. Consequently, a preservative paste composition was obtained.

Example 2

(38) A supplemental/remedial preservative paste composition was prepared by blending together in the order listed; 33.30 parts water, 3.00 parts of a fine copper dispersion comprised of 33.3% copper hydroxide, 10.00 parts glycerin, 2.00 parts of a commercially available cellulose ether thickener, 43.70 parts sodium tetraborate decahydrate, 1.00 part calcium sulfate filler and 7.00 parts attapulgite clay thickener. This remedial preservative paste contained 1.00 parts copper as derived from the fine copper hydroxide dispersion for a weight ratio of 43.70 parts boron compound to 1.00 part copper.

(39) The supplemental/remedial preservative paste composition formulated according to the above example was applied to a wooden substrate using a trowel and was found to have desirable physical properties including viscosity, spreadability and adherence for application to in-service utility poles, cross-ties and other wooden structures. Consequently, a preservative paste composition was obtained.

Example 3

(40) A supplemental/remedial preservative paste composition was prepared by blending together in the order listed; 30.24 parts water, 1.50 parts of a fine copper dispersion comprised of 33.3% basic copper carbonate, 10.00 parts glycerin, 3.00 parts of a commercially available cellulose ether thickener, 47.76 parts sodium tetraborate decahydrate, 1.50 part calcium sulfate filler and 6.00 parts attapulgite clay thickener. This remedial preservative paste contained 0.50 parts copper as derived from the fine basic copper carbonate dispersion for a weight ratio of 95.52 parts boron compound to 1.00 part copper.

(41) The supplemental/remedial preservative paste composition formulated according to the above example was applied to a wooden substrate using a trowel and was found to have desirable physical properties including viscosity, spreadability and adherence for application to in-service utility poles, cross-ties and other wooden structures. Consequently, a preservative paste composition was obtained.

Example 4

(42) A supplemental/remedial preservative paste composition was prepared by blending together in the order listed; 44.60 parts water, 0.02 parts bifenthrin, 3.00 parts of a fine copper dispersion comprised of 33.3% cupric oxide, 0.50 parts of a commercially available cellulose ether thickener, 43.70 parts sodium tetraborate decahydrate, and 8.2 parts attapulgite clay thickener. This remedial preservative paste contained 1.00 parts copper as derived from the fine cupric oxide dispersion for a weight ratio of 43.7 parts boron compound to 1.00 part copper.

Example 5

(43) A supplemental/remedial preservative paste composition is prepared by blending together in the order listed; 34.00 parts water, 0.10 parts tebuconazole, 2.25 parts of a fine copper dispersion comprised of 33.3% basic copper carbonate, 10.00 parts glycerin, 3.00 parts of a commercially available cellulose ether thickener, 21.85 parts sodium tetraborate decahydrate, 21.85 parts boric acid, 1.00 part calcium sulfate filler and 6.0 parts attapulgite clay thickener.

(44) This remedial preservative paste contains 0.75 parts copper as derived from the fine basic copper carbonate dispersion for a weight ratio of 58.27 parts boron compound to 1.00 part copper.

Example 6

(45) A supplemental/remedial preservative paste composition was prepared by blending together in the order listed; 44.6 parts water, 0.50 parts of a commercially available cellulose ether thickener, 3.00 parts of a fine copper hydroxide dispersion comprised of 33.3% copper carbonate, 0.10 parts bifenthrin, 0.10 parts tebuconazole, 43.70 parts sodium tetraborate decahydrate, 6.5 parts attapulgite clay thickener and 1.5 parts calcium sulfate filler. This remedial preservative paste contained 1.00 parts copper as derived from the fine copper carbonate dispersion for a weight ratio of 43.7 parts boron compound to 1.00 part copper.

(46) Penetration testing performed on the paste composition formulated according to the example above showed a penetration of 216 tmm. In addition, the supplemental/remedial preservative paste composition formulated according to the above example was applied to a wooden substrate using a trowel and was found to have desirable physical properties including viscosity, spreadability and adherence for application to in-service utility poles, cross-ties and other wooden structures. Consequently, a preservative paste composition was obtained.

Example 7

(47) A supplemental/remedial preservative paste composition was prepared by blending together in the order listed; 37.00 parts water, 6.51 parts of a fine copper dispersion comprised of 31.6% cuprous oxide, 0.50 parts of a commercially available cellulose ether thickener, 50.00 parts sodium tetraborate decahydrate, and 6.00 parts attapulgite clay thickener. This remedial preservative paste contained 2.06 parts copper as derived from the fine cuprous oxide dispersion for a weight ratio of 24.27 parts boron compound to 1.00 part copper.

(48) Penetration testing performed on the paste composition formulated according to the example above showed a penetration of 275 tmm. Further, the paste composition formulated according to the above example was brushed to 18 inches of the below ground section of an in-service utility pole. This paste was found to have desirable physical properties including viscosity, spreadability and adherence for application to in-service utility poles, cross-ties and other wooden structures. Consequently, a preservative paste composition was obtained.

Example 8

(49) A supplemental/remedial preservative paste composition was prepared by blending together in the order listed; 44.6 parts water, 3.00 parts of a fine copper dispersion comprised of 33.3% copper carbonate, 0.70 parts pigmented dyes, 0.50 parts of a commercially available cellulose ether thickener, 43.70 parts sodium tetraborate decahydrate, and 7.50 parts attapulgite clay thickener. This remedial preservative paste contained 1.0 parts copper as derived from the fine copper carbonate dispersion for a weight ratio of 43.7 parts boron compound to 1.00 part copper.

(50) Penetration testing performed on the paste composition formulated according to the example above showed a penetration of 211 tmm. Further, the paste composition formulated according to the above example was brushed to 18 inches of the below ground section of an in-service utility pole by an experienced preservative chemical applicator. This paste was found to have desirable physical properties including viscosity, spreadability and adherence for application to in-service utility poles, cross-ties and other wooden structures. Consequently, a preservative paste composition was obtained.

(51) Further, the paste formed was applied to the surface of southern pine dimensional lumber that had previously been vacuum-pressure impregnated with water. The lumber was saturated with water to simulate moisture regimes that are typically present within the ground-line region of in-service utility poles and other wooden structures and that is required to provide mobility of the preservative paste into the wood substrate. The paste was applied at a thickness of a sixteenth of an inch and sealed to the lumber with a water impermeable wrap such that is used in commercial practice. At periods of 2, 4 and 6 weeks, small incremental wafers were taken from the treated sections of the lumber. Wafers were sprayed with the copper penetration reagent Chrome Azurol S in accordance with American Wood Protection Association's (AWPA) Standard A3-08 (which is incorporated herein by reference in its entirety), Method 2, Method for Determining Penetration of Copper-Containing Preservatives. It was determined by visual inspection that copper had penetrated, or diffused through the wood up to a inch from the surface of application. It was further visually determined that boron had penetrated the wood up to 1 inches from the treated surface using AWPA Standard A3-08, Method 17, Standard Method for Determining Penetration of Boron-Containing Preservatives and Fire Retardants.

Example 9

(52) A supplemental/remedial preservative paste composition was prepared by blending together in the order listed; 45.05 parts water, 3.00 parts of a fine copper dispersion comprised of 33.3% copper carbonate, 0.75 parts of a commercially available cellulose ether thickener, 43.70 parts sodium tetraborate decahydrate, and 7.50 parts attapulgite clay thickener. This remedial preservative paste contained 1.00 parts copper as derived from the fine copper carbonate dispersion for a weight ratio of 43.7 parts boron compound to 1.00 part copper.

(53) Penetration testing performed on the paste composition formulated according to the example above showed a penetration of 220 tmm.

(54) Further, the paste composition formulated according to the above example was brushed to 18 inches of the belowground section of 10 utility-pole sections installed in a fieldtest plot located in Gainesville, Fla. The paste product was installed by an experienced preservative chemical applicator and was found to have desirable physical properties including viscosity, spreadability and adherence for application to in-service utility poles, cross-ties and other wooden structures.

(55) Chemical penetration and retention was assessed at 12 months following treatment with the paste composition formulated according to the above example. Copper was detected at fungitoxic levels in the outer inch of the test poles at 12 months following treatment. Boron was detected at levels above the fungitoxic threshold level up to a depth of 3.0 inches from the pole surface after 12 months. Thus desirable chemical penetration and retention levels were obtained.

Example 10

(56) A supplemental/remedial preservative paste composition is prepared by blending together in the order listed; 33.66 parts water, 0.04 parts bifenthrin, 0.10 parts tebuconazole, 6.00 parts of a fine copper dispersion comprised of 33.3% basic copper carbonate, 10.00 parts glycerin, 0.50 parts of a commercially available cellulose ether thickener, 21.85 parts sodium tetraborate decahydrate, 21.85 parts sodium fluoride, and 6.0 parts attapulgite clay thickener.

(57) This remedial preservative paste contains 2.00 parts copper as derived from the fine basic copper carbonate dispersion for a weight ratio of 10.92 parts boron compound to 1.00 part copper and 10.92 parts fluoride compound to 1.00 part copper.

Example 11

(58) A supplemental/remedial preservative paste composition was prepared by blending together in the order listed; 44.6 parts water, 3.00 parts of a fine copper dispersion comprised of 33.3% copper hydroxide, 0.70 parts pigmented dyes, 0.50 parts of a commercially available cellulose ether thickener, 43.70 parts boric acid, and 7.50 parts attapulgite clay thickener. This remedial preservative paste contained 1.0 parts copper as derived from the fine copper hydroxide dispersion for a weight ratio of 43.7 parts boron compound to 1.00 part copper.

Example 12

(59) A supplemental/remedial preservative paste composition was prepared by blending together in the order listed; 44.6 parts water, 3.00 parts of a fine copper dispersion comprised of 33.3% copper hydroxide, 0.70 parts pigmented dyes, 0.50 parts of a commercially available cellulose ether thickener, 43.70 parts sodium fluoride, and 7.50 parts attapulgite clay thickener. This remedial preservative paste contained 1.0 parts copper as derived from the fine copper hydroxide dispersion for a weight ratio of 43.7 parts fluoride compound to 1.00 part copper.

Example 13

(60) A supplemental/remedial preservative paste composition is prepared by blending together in the order listed; 41.79 parts water, 9.38 parts propylene glycol, 1.5 parts of a fine basic copper carbonate dispersion comprised of 33.3% copper, 0.33 parts didecyldimethylammonium carbonate/bicarbonate, 2.00 parts of a commercially available cellulose ether thickener, 36.0 parts disodium octaborate tetrahydrate, 2.0 part calcium sulfate filler and 7.0 parts attapulgite clay thickener.

(61) This remedial preservative paste contains 0.50 parts copper as derived from the fine basic copper carbonate dispersion for a weight ratio of 72.00 parts boron compound to 1.00 part copper.

Example 14

(62) A supplemental/remedial preservative paste composition was prepared by blending together in the order listed; 44.6 parts water, 3.00 parts of a fine copper dispersion comprised of 33.3% copper carbonate, 0.70 parts pigmented dyes, 0.50 parts of a commercially available cellulose ether thickener, 43.70 parts sodium tetraborate decahydrate, and 7.50 parts attapulgite clay thickener. This remedial preservative paste contained 1.0 parts copper as derived from the fine copper carbonate dispersion for a weight ratio of 43.7 parts boron compound to 1.00 part copper.

(63) A series of preservative treating formulations were prepared by diluting the paste composition formulated according to the example above with water. The stable dispersions were used to treat southern pine test stakes measuring 0.750.750.75 inches by the full-cell process. Stable dispersions were prepared to vacuum-pressure treat the test blocks rather than apply the preservative paste to the surface of the pine test blocks, which may have acted as a barrier or strong repellent. The treated cubes were exposed to two common test fungi to evaluate the bio-efficacy of the preservative formulations following procedure described in AWPA Standard E10-12, Standard Method of Testing Wood Preservatives by Laboratory Soil-Block Cultures. Upon completion of the soil-block test, the cubes were found to have less than 2% weight loss, indicating essentially no fungal attack to the treated cubes. In comparison, untreated wood cubes had approximately 60% weight loss after being exposed to the test fungi.

Example 15

(64) A series of preservative treating formulations were prepared by diluting the paste composition formulated according to Example 14 above with water. The stable dispersions were used to treat southern pine test stakes measuring 0.750.750.75 inches by the full-cell process. Stable dispersions were prepared to vacuum-pressure treat the test blocks rather than apply the preservative paste to the surface of the pine test blocks, which may have acted as a barrier or strong repellent. The treated cubes were exposed to termites to evaluate the resistance of the preservative formulations following the procedure described in AWPA Standard E1-12, Standard Method for Laboratory Evaluation to Determine Resistance to Subterranean Termites. Upon completion of the termite test, the cubes were found to have less than 5% weight loss with visual ratings of 8.2 to 9.4 (scale of 0 to 10, 0 being complete failure and 10 having no attack), indicating excellent protection against termite attack. In comparison, untreated wood cubes had approximately 35% weight loss and a visual rating of 3.8 after being exposed to the test termites.

Example 16

(65) A supplemental/remedial preservative paste composition was prepared in accordance with Example 14. The paste composition was tested for volatile organic compounds (VOC) content in accordance with EPA Method 8620, Volatile Organic Compounds by Gas Chromatography Mass Spectrometry (GC/MS).

(66) Two commercially available remedial preservative paste formulations were also tested for VOC content in accordance with EPA Method 24, SCAQMD 304 or Modified EPA Method 8620 (which are incorporated by reference in their entireties). The first commercially available paste formulation, known to contain an oil-borne copper naphthenate complex was analyzed to have a VOC content of 340 grams VOC/liter coating. The second commercial paste product was formulated according to U.S. Pat. No. 8,221,797, which contained a micronized form of oxine copper that had a VOC content of 36 grams VOC/liter coating. Testing of a remedial preservative paste composition made in accordance with the present invention was analyzed to have a non-detectable level of VOCs (0.1% LOD). An oil-borne copper naphthenate solution containing 2% copper was analyzed to have a VOC content of 698 grams VOC/liter coating. Consequently, a remedial preservative paste formulation that is essentially free of volatile organic compounds was achieved.

Example 17

(67) The supplemental/remedial preservative paste composition of Example 14 was continuously extruded through a inch diameter aperture and subsequently cut into 3 inch lengths. The rods were then dried at 90 F. for 24 hours. The resulting preservative rods were found to be structurally sound, uniformly shaped and preferable for insertion into predrilled holes such that are drilled into in-service utility poles, piling, cross-ties and other wooden structures for the afterprotection against wood destroying decay fungi. Further, the rods were placed on a wet sponge partially submerged in a water bath to allow continual wicking of water from the bath to the rod. After six weeks it was determined through analysis that the water bath contained appreciable levels of copper and boron. Consequently, a preservative rod composition was achieved.

Example 18

(68) The supplemental/remedial preservative paste composition of Example 9 was injected into inch holes drilled into an in-service utility pole containing a large decay void. The preservative paste formulation was found to be easily pumped or transferred with standard pneumatic pumping equipment or by gravity feed. The pole section containing the void was subsequently dissected and the paste composition was found to have completely filled the void and achieved intimate contact with the surfaces of the wood such that would provide adequate diffusion of biocide to the wood substrate in the presence of moisture or liquid water. Consequently, a preservative internal treatment composition was achieved.

Example 19

(69) The supplemental/remedial preservative paste composition of Example 10 was rolled onto a polyethylene sheet to a uniform thickness of 0.0625 inches. The subsequent paste/support system was cut to 21 inches in length and applied to the below ground portion of an in-service utility pole such that the entire circumference of the pole was incased to 18 inches below ground. As the paste/support system was handled and transported the paste did not slump, run or drip off of the supporting material. Removal of the paste/support system from the pole shortly after application found that the paste composition adhered and maintained intimate contact with to the pole surface such that would provide adequate diffusion of the biocide to the wood substrate in the presence of moisture or liquid water. Consequently, a preservative wrap or bandage composition was achieved.

Example 20

(70) The preservative penetration and retention characteristics in full-size southern pine pole sections initially treated with pentachlorophenol discovered from field testing the supplemental/remedial preservative paste composition formulated according to Example 9 above was compared to known commercially available paste formulations and associated third party generated penetration and retention data.

(71) Chemical penetration and retention was assessed at 12 months following treatment with the paste composition formulated according to Example 9 above. Chemical penetration and retention may be measured by any method known in the art. Copper was detected at the fungitoxic level of 0.04 pounds per square foot (PCF) in the outer inch of the test poles at 12 months following treatment. The Oregon State University-Utility Pole Research Cooperative (OSU-UPRC) has established a threshold level for copper of 0.04 PCF when used in remedial preservative applications (OSU-UPRC 2013 Annual Report). This value also corresponds with the copper threshold retention level listed for copper naphthenate in AWPA Use Category 3B (AWPA 2013 Book of Standards).

(72) The UPRC established a field trial in November 2004 to evaluate the performance of external supplemental preservative pastes on southern pine utility poles initially treated with pentachlorophenol. This study included 3 commercially available copper containing paste formulations each of which contained copper at 2% wt/wt that had been complexed, or solubilized with the use of organic solvents. Copper levels for Formulation A, a fuel oil based preservative paste that utilized an oil based naphthenic acid to complex the copper source, were found to be 70% in excess of the established copper threshold level of 0.04 PCF in the outer inch of the test poles. Copper levels for Formulation B, a water based preservative paste that utilized monoethanolamine to complex the copper source, were found to be 168% in excess of the established copper threshold level in the outer inch of the test poles. Copper levels for Formulation C, a water based preservative paste that utilized a water dispersible naphthenic acid to complex the copper source, were found to be 167% in excess of the established copper threshold level 0.04 PCF in the outer inch of the test poles. The data for Formulation C represents 2 year data as the 1 year data was unavailable.

(73) The uncontrolled mobility of the copper component from current paste compositions as demonstrated from the UPRC study is a concern from a performance standpoint. Water- and oil-soluble copper complexes provide an uncontrolled dose to the wooden structure to be preserved that quickly disperses beyond the intended zone of protection within the wooden structure and rapidly depletes the copper reservoir contained within the residual paste composition diminishing the ability of the treatment to provide prolonged periods of protection from the action of decay and wood destroying insects such as termites. The amount of copper that is delivered by prior art formulations into the outer shell of the test poles is excessive and unnecessary as levels are far in excess of fungitoxic thresholds and a large degree of protection is also afforded by co-biocides in each of the formulations and by any residual chemical remaining in the poles from the initial preservative treatment.

(74) The slow or controlled release of the micronized copper carbonate from the supplemental/remedial preservative paste composition made in accordance with this invention was an unexpected and surprising occurrence.