Wood treatment method
View Patent ↗A method for treating wood to inhibit leaching of copper compounds into the environment. The method comprises treating the wood with a copper-containing wood preservative and a latex copolymer.
1. A method for treating wood; said method comprising adding to wood:
(a) a copper-containing wood preservative; and
(b) a latex copolymer comprising polymerized units of a monomer X and a monomer Y;
wherein the latex copolymer comprises at least 5 wt % of monomer X derived units;
wherein the latex copolymer comprises no more than 1,000 ppm residual monomer X;
wherein monomer X is N-vinylimidazole;
wherein monomer Y is selected from carboxylic acids, carboxylic acid salts, carboxylic acid esters, organosulfuric acids, organosulfuric acid salts, sulfonic acids, sulfonic acid salts, phosphonic acids, phosphonic acid salts, vinyl esters, (meth)acrylamides, C 8 -C 20 aromatic monomers containing at least one exocyclic ethylenic unsaturation or combinations thereof.
2. The method of claim 1 , wherein the latex copolymer comprises >5 to 50 wt % of units derived from monomer X and 95 to 50 wt % of units derived from monomer Y.
3. The method of claim 1 , wherein the latex copolymer comprises 25 to 50 wt % of units derived from monomer X and 75 to 50 wt % of units derived from monomer Y.
4. The method of claim 3 wherein monomer Y is selected from carboxylic acids, carboxylic acid esters or combinations thereof.
5. The method of claim 4 , wherein monomer Y is at least one alkyl (meth)acrylate.
6. The method of claim 5 , wherein the latex copolymer is added to treated wood containing a copper-containing wood preservative.
7. The method of claim 6 , wherein the latex copolymer is added in an amount from 0.05 wt % to 2 wt %.
8. The method of claim 7 , wherein monomer Y is butyl acrylate.
9. The method of claim 1 wherein the latex copolymer is added to treated wood containing a copper-containing wood preservative.