Nonleachable Composition and Method to Use

Abstract

This invention relates to a nonleachable waterborne wood preservative composition that combines one or more resin acids, mostly or fully in the carboxylate anion form, with one or more organic biocides to enhance the efficacy of relatively high-cost organic biocides. Resin acids are cost effective and environmentally safe, and therefore can be used as a low-cost and environmentally-benign additive to help protect wood against wood-destroying fungi. Furthermore, wood treated with a waterborne resin acid formulation will have enhanced water repellency, which will result in better dimensional stability for wood exposed to water. This invention also provides a method for the use of the described composition.

Description

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

A more complete appreciation of the present invention and many attendant advantages thereof will be readily understood by reference to the following detailed description of the invention when considered in connection with the accompanying drawings, wherein:

FIG. 1 is a graph showing average compression strength of cottonwood wafers treated with the present composition of a resin acid and an organic biocide combined, and samples that were treated with only the organic biocide with the wood wafers treated by the two preservative systems then exposed to white rot decay fungus in the ager block laboratory decay test.

FIG. 2 is a graph showing average compression strength of cottonwood wafers treated with the present composition of a resin acid and an organic biocide combined, or treated with the biocide alone, with the wood wafers treated by the two preservatives exposed to white rot decay fungus in the ager block laboratory decay test.

FIG. 3 is a graph showing average compression strength of cottonwood wafers treated with an organic biocide alone, with half of the wafers then treated again with a waterborne resin acid solution, with the wood wafers then exposed to white rot decay fungus in the ager block laboratory decay test.

Claims

1. A nonleachable composition consisting essentially of an effective amount of at least one organic biocide, a carboxylated anion solution of at least one resin acid and liquid carrier medium.

2. The composition of claim 1 wherein the at least one organic biocide is selected from the group consisting of: i. an azole biocide;ii. 2-(thiocyanomethylthio)benzothiazole;iii. 3-iodo-2-propynylbutyl carbamate;iv. a quaternary ammonium biocide;v. chlorothalonil;vi. dichlofluanid;vii. 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one; andviii. methylene bis-thiocyanate.

3. The composition of claim 1, further comprising an effective amount of nonbiocidal additive.

4. The composition of claim 1, wherein the purity of the at least one resin acid is between 40% to 100%.

5. The composition of claim 1, further comprising a liquid carrier medium of at least 40% water and an organic co-solvent that is soluble in water.

6. The composition of claim 2, wherein the azole is selected from the group consisting of cyproconazole, propiconazole and tebuconazole.

7. The composition of claim 1, wherein the concentration of the at least one organic biocide is between 0.0001% to 10% by weight of the nonleachable composition that will be employed to treat the wood.

8. The composition of claim 1, wherein the concentration of the at least one resin acid is between 0.1 to 25% by weight of the nonleachable composition.

9. A method of preventing degradation of wood product by comprising: treating a wood product with effective amount of the nonleachable composition of claim 1.

10. The method of claim 9 wherein the at least one organic biocide is selected from the group consisting of: ix. an azole biocide;x. 2-(thiocyanomethylthio)benzothiazole;xi. 3-iodo-2-propynylbutyl carbamate;xii. a quaternary ammonium biocide;xiii. chlorothalonil;xiv. dichlofluanid;xv. 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one; andxvi. methylene bis-thiocyanate.

11. A method to prevent the degradation of wood product comprising the steps of: a) treating a wood product with an aqueous solution comprising at least one resin acid carboxylate anion for a sufficient amount of time for said aqueous solution to be adsorbed by said wood product; andb) treating said wood product with at least one organic biocide in solution for a sufficient amount of time for said solution to be adsorbed by said wood product.

12. The method of claim 11 wherein the at least one organic biocide is selected from the group consisting of: xvii. an azole biocide;xviii. 2-(thiocyanomethylthio)benzothiazole;xix. 3-iodo-2-propynylbutyl carbamate;xx. a quaternary ammonium biocide;xxi. chlorothalonil;xxii. dichlofluanid;xxiii. 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one; andxxiv. methylene bis-thiocyanate.

13. A method to make a nonleachable composition comprising the steps of: admixing at least one organic biocide, the salt of at least one resin acid and a liquid carrier medium to form a nonleachable composition.

14. The method of claim 13 wherein the at least one organic biocide is selected from the group consisting of: i. an azole biocide;ii. 2-(thiocyanomethylthio)benzothiazole;iii. 3-iodo-2-propynylbutyl carbamate;iv. a quaternary ammonium biocide;v. chlorothalonil;vi. dichlofluanid;vii. 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one; andviii. methylene bis-thiocyanate.