Wood preservative formulations comprising isothiazolones which provide protection against surface staining

Abstract

The present invention provides a wood preservative formulation comprising an isothiazolone, an organic fungicidal timber decay preservative and an unsaturated carboxylic or sulphonic acid, salt or precursor thereof. The formulations of the invention are surprisingly effective at protecting wood and other cellulosic substrates, in particular at providing prolonged protection against in-service surface staining. The invention also provides methods for treating wood and other cellulosic substrates with said formulations.

1 . A wood preservative formulation comprising an isothiazolone, an organic fungicidal timber decay preservative and an unsaturated carboxylic or sulphonic acid, salt or precursor thereof. 
     
     
         2 . The formulation as defined in  claim 1 , wherein the unsaturated carboxylic or sulphonic acid, salt or precursor thereof is an unsaturated carboxylic or sulphonic acid or alkali metal salt thereof. 
     
     
         3 . The formulation as defined in  claim 1 , wherein the unsaturated carboxylic or sulphonic acid, salt or precursor thereof is an unsaturated cyclic carboxylic or sulphonic acid, salt or precursor thereof. 
     
     
         4 . The formulation as defined in  claim 3 , wherein the unsaturated carboxylic or sulphonic acid, salt or precursor thereof is an aromatic acid, salt or precursor thereof. 
     
     
         5 . The formulation as defined in  claim 4  wherein the aromatic acid is of formula (I): 
       
         
           
           
               
               
           
         
         wherein Y denotes CO 2 M or SO 3 M; 
         each R independently denotes C 1 -C 12  alkyl, OH, OMe, OEt, NH 2 , NMe 2 , CO 2 M or halogen, 
         wherein two R groups may optionally form naphthyl; 
         M denotes H, K or Na; and 
         m denotes 0 to 5. 
       
     
     
         6 . The formulation as defined in  claim 5 , wherein the aromatic acid or salt thereof is selected from the group consisting of benzoic acid and sodium benzoate. 
     
     
         7 . The formulation as defined in  claim 3 , wherein the cyclic carboxylic or sulphonic acid is a resin acid or salt thereof. 
     
     
         8 . The formulation as defined in  claim 7 , wherein the resin acid or salt thereof is selected from the group consisting of abietic acid, sodium abietate, pimaric acid and sodium pimarate. 
     
     
         9 . The formulation as defined in  claim 1 , wherein the unsaturated carboxylic or sulphonic acid, salt or precursor thereof is a linear unsaturated carboxylic acid, salt or precursor thereof. 
     
     
         10 . The formulation as defined in  claim 9 , wherein the unsaturated carboxylic acid, salt or precursor thereof is selected from the group consisting of oleic acid, sodium oleate or potassium oleate. 
     
     
         11 . The formulation as defined in  claim 1 , wherein the isothiazolone is of formula (II): 
       
         
           
           
               
               
           
         
         wherein 
         R 1  denotes hydrogen, optionally substituted C 1 -C 18  alkyl, C 2 -C 8  alkenyl or alkynyl, C 2 -C 8  haloalkynyl, optionally substituted C 3 -C 12  cycloalkyl, optionally substituted aralkyl having up to 10 carbon atoms, or optionally substituted aryl having up to 10 carbon atoms; and 
         R 2  and R 3  independently denote hydrogen, halogen or C 1 -C 4  alkyl, or together R 2  and R 3  may provide a 1,2 benzisothiazolin-3-one group. 
       
     
     
         12 . The formulation as defined in  claim 11 , wherein,
 R 1  denotes hydrogen or C 1 -C 8  alkyl; and   R 2  and R 3  independently denote chloro or hydrogen, or together R 2  and R 3  may provide a 1,2 benzisothiazolin-3-one group.   
     
     
         13 . The formulation as defined in  claim 12 , wherein the isothiazolone is selected from the group consisting of methylisothiazol-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one, 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one, octylisothiazol-3-one, 1,2-benzisothiazol-3(2H)-one, N-methyl-1,2-benzisothiazol-3-one and N-(n-butyl)-1,2-benzisothiazol-3-one. 
     
     
         14 . The formulation as defined in  claim 13 , wherein the isothiazolone is n-octyl-4-isothiazolin-3-one. 
     
     
         15 . The formulation according to  claim 1 , wherein the organic fungicidal timber decay preservative is an azole. 
     
     
         16 . The formulation according to  claim 15 , wherein the azole compound is an imidazole, a 1,2,4-triazole, or mixtures of both, preferably a 1,2,4-triazole. 
     
     
         17 . The formulation as defined in  claim 16 , wherein the imidazole is a benzimidazole. 
     
     
         18 . The formulation as defined in  claim 17 , wherein the imidazole is selected from the group consisting of thiabendazole, imazalil, carbendazim and prochloraz. 
     
     
         19 . The formulation as defined in  claim 16 , wherein the 1,2,4-triazole is selected from the group consisting of
 compounds of formula (IV):   
       
         
           
           
               
               
           
         
         wherein R 5  represents a branched or straight chain C 1-5  alkyl group; and 
         R 6  represents a phenyl group optionally substituted by one or more substituents selected from halogen, C 1-3  alkyl, C 1-3  alkoxy, phenyl or nitro; and 
         compounds of formula (V): 
       
       
         
           
           
               
               
           
         
         wherein R 7  is as defined for R 6  above; and 
         R 8  represents a hydrogen atom or a branched or straight chain C 1-5  alkyl group; or selected from the group consisting of triadimefon, triadimenol, triazbutil, cyproconazole, difenoconazole, fluquinconazole, flusilazole, uniconazole, diniconazole, bitertanol, hexaconazole, flutriafol, epoxyconazole, tetraconazole, penconazole, ipconazole, prothiazole and mixtures thereof. 
       
     
     
         20 . The formulation as defined in  claim 19 , wherein the 1,2,4-triazole is selected from the group consisting of triadimefon, triadimenol, triazbutil, propiconazole, cyproconazole, difenoconazole, fluquinconazole, tebuconazole, flusilazole, uniconazole, diniconazole, bitertanol, hexaconazole, azaconazole, flutriafol, epoxyconazole, tetraconazole, penconazole, ipconazole, prothiazole and mixtures thereof. 
     
     
         21 . The formulation as defined in  claim 19 , wherein the 1,2,4-triazole is selected from the group consisting of propiconazole, tebuconazole, and mixtures thereof. 
     
     
         22 . The formulation as defined in  claim 15 , wherein the ratio of azole to isothiazolone is 10:1 to 2:1 w/w. 
     
     
         23 . The formulation as defined in  claim 1 , wherein the formulation is free of haloalkynyl compounds. 
     
     
         24 . The formulation as defined in  claim 1 , wherein the formulation is in a liquid form. 
     
     
         25 . The formulation as defined in  claim 24 , wherein the formulation is an emulsion. 
     
     
         26 . A wood preservative kit comprising:
 (i) a formulation comprising an organic fungicidal timber decay preservative and an unsaturated carboxylic or sulphonic acid, salt or precursor thereof; and   (ii) a formulation comprising an isothiazolone.   
     
     
         27 . A treatment solution comprising the formulation of  claim 1 , wherein the total amount of isothiazolone in the solution is 500 ppm or less. 
     
     
         28 . A method of protecting a substrate of wood or other cellulosic material which comprises applying to the substrate or treating the substrate such that it effectively receives a formulation as defined in  claim 1 . 
     
     
         29 . A substrate made of wood or other cellulosic material treated with a formulation as claimed in  claim 1 . 
     
     
         30 . A substrate as defined in  claim 29 , wherein the organic fungicidal timber decay preservative is an azole, and wherein the ratio of azole to isothiazolone is at least 3:2. 
     
     
         31 - 32 . (canceled)