Method and composition for treating wood with pentachlorophenol

Abstract

A composition for impregnating wood with pentachlorophenol is prepared by dissolving pentachlorophenol in .[.a petroleum fraction.]. .Iadd.an organic solvent .Iaddend.at least 50% of which will distill above 485° F., and mixing the resulting solution with water to produce a finely divided dispersion of the solution in water.

I claim: 
     
       1. A method of impregnating wood with pentachlorophenol comprising the steps of preparing a solution of about 25 to 55 percent by weight of pentachlorophenol in an organic solvent comprising a petroleum fraction at least 50% of which will distill above 485° F., preparing a finely divided dispersion of the solution in water in which the pentachlorophenol content is from 0.1 to 10 percent by weight, and impregnating wood with the dispersion. 
     
     
       2. A composition for impregnating wood comprising a finely divided dispersion in water of a solution of about 25 to 55 percent by weight of pentachlorophenol in an organic solvent comprising a petroleum fraction at least 50% of which will distill above 485° F., the pentachlorophenol content of the dispersion being from 0.1 to 10 percent by weight. .Iadd. 
     
     
       3.  A method of preserving wood against decay and attack by insects and fungi by impregnation of the wood with pentachlorophenol, said method comprising the steps of preparing a solution of about 25 to about 55 percent by weight of pentachlorophenol in an organic solvent, preparing a finely divided dispersion of the solution in water in which the pentachlorophenol content is from 0.1 to 10 percent by weight, and impregnating wood with the dispersion. .Iaddend. .Iadd.4. The method of claim 3 wherein the organic solvent is selected from the group consisting of high-boiling petroleum fractions, long chain alcohols, diols, ethers, aldehydes, ketones, and mixtures of high-boiling petroleum fractions, long chain alcohols, diols, ethers, aldehydes, and ketones. .Iaddend. .Iadd.5. The method of claim 3 wherein at least 50% of the organic solvent will distill about 485° F. .Iaddend. .Iadd.6. The method of claim 3 wherein the finely divided dispersion comprises a water-soluble dispersing agent in an amount from about 10 to about 40 percent by weight of the solution. .Iaddend. .Iadd.7. The method of claim 6 wherein the dispersing agent comprises a surfactant selected from the group consisting of organic 
     
     
        sulfates and sulfonates. .Iaddend. .Iadd.8.  The method of claim 3 further comprising a step of drying the wood after impregnation with the dispersion to remove substantially all of the water so that droplets of pentachlorophenol solution are substantially completely distributed throughout the treated portion of the wood. .Iaddend. .Iadd.9. Wood preserved against decay and attack by insects and fungi by treatment according to the method of claim 1, 3, 4, 5, 6, 7, or 8 wherein the pentachlorophenol content of the impregnated wood is at least about 0.3 lbs per cubic foot. .Iaddend. .Iadd.10. The wood of claim 9 wherein the pentachlorophenol is substantially nonleachable from the impregnated wood. .Iaddend. .Iadd.11. The wood of claim 9 wherein penetration of the pentachlorophenol into the wood is substantially the same as that penetration achievable by treatment with a conventional oil solution method. .Iaddend. .Iadd.12. A composition for preparing a water dispersion for impregnating wood with pentachlorophenol comprising a solution of pentachlorophenol in an organic solvent, the solution containing from about 25 to about 55 percent by weight of pentachlorophenol, and a water-soluble dispersing agent in an amount sufficient to form a stable 
     
     
        finely divided dispersion of the solution in water. .Iaddend. .Iadd.13. The composition of claim 12 wherein the organic solvent is selected from the group consisting of high-boiling petroleum fractions, long chain alcohols, diols, ethers, aldehydes, ketones, and mixtures of high-boiling petroleum fractions, long chain alcohols, diols, ethers, aldehydes, and ketones. .Iaddend. .Iadd.14. The composition of claim 12 wherein at least 50% of the organic solvent will distill above 485° F. .Iaddend. .Iadd.15. The composition of claim 12 wherein the dispersing agent is present in an amount from about 10 to about 40 percent by weight of the solution. .Iaddend. .Iadd.16. The composition of claim 15 wherein the dispersing agent comprises a surfactant selected from the group consisting of organic sulfates and sulfonates. .Iaddend. .Iadd.17. The composition of claim 16 wherein the dispersing agent comprises a salt of dodecyl benzene sulfonic acid. .Iaddend. .Iadd.18. A finely divided dispersion prepared by mixing water with the composition of claim 12, 13, 14, 15, 16, or 17 wherein the pentachlorophenol content of the dispersion is from about 0.1 to about 10 percent by weight. .Iaddend. .Iadd.19. The dispersion of claim 18 wherein the pentachlorophenol content of the dispersion is from about 4 to about 7 percent by weight. .Iaddend.