Wood preservation method

• US 20060093743A1
• Filed: 10/28/2004
• Published: 05/04/2006
• Est. Priority Date: 10/28/2004
• Status: Abandoned Application

• Current Assignee: Tank Fab Inc.
• Original Assignee: Tank Fab Inc.
• Inventors: Lippincott, Thomas E.
• Application Number:
  US10/975,635
• Publication Number:
  US 20060093743A1
• Time in Patent Office: Days
• US Class Current: 427/351
• CPC Class Codes: B27K 3/0207 Pretreatment of wood before impregnation
• CPC Class Codes: B27K 3/08 Impregnating by pressure , e.g. vacuum impregnation
• CPC Class Codes: B27K 3/36 Aliphatic compounds
• CPC Class Codes: B27K 3/50 Mixtures of different organic impregnating agents
• CPC Class Codes: D21H 17/13 Silicon-containing compounds
• CPC Class Codes: D21H 21/36 Biocidal agents, e.g. fungicidal, bactericidal, insecticidal agents

Abstract

Wood is pressure treated in a pressure autoclave by drawing an initial vacuum in the autoclave to remove air from the autoclave and the wood; filling the autoclave with inert gas while the autoclave is under vacuum; filling the chamber with a preservative comprised of a silane compound, a liquid hydrocarbon solvent, and optional pesticides; pressurizing the autoclave to impregnate the wood with the preservative; draining the preservative from the autoclave; and applying a final vacuum to the autoclave to remove excess solvent from the autoclave and the wood.

Claims

1. A method of pressure treating wood in a pressure autoclave comprising:

a) drawing an initial vacuum to remove air from the autoclave and the wood;

b) filling the autoclave with inert gas while the autoclave is under vacuum;

c) filling the chamber with a preservative comprised of a silane and a liquid hydrocarbon solvent;

d) pressurizing the autoclave to impregnate the wood with the preservative; and

e) applying a final vacuum to the autoclave to remove excess solvent.

2. The method of claim 1, wherein said preservative also includes a pesticide.

3. The method of claim 1, wherein said inert gas is nitrogen.

4. The method of claim 1, wherein the initial vacuum is from about 1 to about 30 inches of Hg.

5. The method of claim 1, wherein the autoclave is pressurized to from about 0 psig to about 500 psig.

6. The method of claim 1, wherein the final vacuum is from about 1 to about 30 inches of Hg.

7. The method of claim 1, wherein the silane compound is a halosilane.

8. The method of claim 1, wherein the solvent is selected from the group consisting of pentane, hexane, heptane, octane, tetrahydrofuran, furan, and mixtures thereof.

9. The method of claim 1, wherein the preservative includes from about 1 to about 5 percent by weight silane.

10. A method of pressure treating wood in a pressure autoclave comprising:

a) drawing an initial vacuum in the autoclave to remove air from the autoclave and the wood;

b) filling the autoclave with inert gas while the autoclave is under vacuum;

c) filling the chamber with a preservative comprised of a halosilane and a liquid hydrocarbon solvent selected from the group consisting of pentane, hexane, heptane, octane, and mixtures thereof;

d) pressurizing the autoclave to impregnate the wood with the preservative;

e) draining the preservative from the autoclave; and

f) applying a final vacuum to the autoclave to remove excess solvent from the autoclave and the wood.

11. The method of claim 10, wherein said preservative compound also includes a pesticide selected from the group consisting of boron compounds, organophosphates, synthetic pyrethroids, and mixtures thereof.

12. The method of claim 10, wherein said inert gas is nitrogen.

13. The method of claim 10, wherein the initial vacuum is from about 1 to about 30 inches of Hg.

14. The method of claim 10, wherein the autoclave is pressurized to from about 0 psig to about 500 psig.

15. The method of claim 10, wherein the final vacuum is from about 1 to about 30 inches of Hg.

16. The method of claim 10, wherein the boron compound is selected from the group consisting of a boric acid and boric anhydride.

17. The method of claim 10, wherein the silane compound is a halosilane.

18. The method of claim 10, wherein the solvent is selected from the group consisting of pentane, hexane, heptane, octane, tetrahydrofuran, furan, and mixtures thereof.

19. The method of claim 10, wherein the preservative includes from about 1 to about 5 percent by weight silane compound.

20. A method of pressure treating wood in a pressure autoclave comprising:

a) drawing an initial vacuum of from about 1 to about 30 inches of Hg in the autoclave to remove air from the autoclave and the wood;

b) filling the autoclave with nitrogen while the autoclave is under vacuum;

c) filling the chamber with a preservative comprised of from about 0.5 to about 10 percent by weight of silane, from about 0.1 to about 10 percent by weight of a pesticide, and a liquid hydrocarbon solvent selected from the group consisting of pentane, hexane, heptane, octane, tetrahydrofuran, furan and mixtures thereof;

d) pressurizing the autoclave to from about 0 psig to about 500 psig to impregnate the wood with the preservative;

e) draining the preservative from the autoclave; and

f) applying a final vacuum of from about 1 to about 30 inches of Hg to the autoclave to remove excess solvent form the autoclave and the wood.

21. The method of claim 20, wherein said pesticide is selected from the group consisting of boron compounds, organophosphates, synthetic pyrethroids, and mixtures thereof.

22. The method of claim 20, wherein said silane is trichloromethylsilane.

23. The method of claim 20, wherein said silane is from about 1 to about 5 percent by weight of said preservative.