Preservation of wood with phenol formaldehyde resorcinol resins
AssigneePolymer Wood Processors, Inc.
InventorJean Lewis, deceased
Life of this patent
Estimating the term…
Abstract
Wood and other cellulose-based products are preserved with a water-based treating solution containing a phenolic resin prepolymer such as phenol formaldehyde resin prepolymer, a resorcinol formaldehyde resin prepolymer and water. The treatment is carried out by exposing the wood or other cellulose-based product, while submerged in the treating solution, to one or more cycles of reduced pressure (i.e. vacuum) and elevated pressure.
Claims14
A treating solution suitable for treating wood and other cellulose-based materials comprising:
- (a) 8% to 30% by weight of a phenolic resin prepolymer;
- (b) 0.8% to 7% by weight of a resorcinol formaldehyde resin prepolymer;
- and
- (c) 64% to 91% by weight of water.
A treating solution suitable for treating wood and other cellulose-based materials, wherein said treating solution is a water dilutable concentrate comprising:
- (a) 40% to 60% by weight of a phenolic resin prepolymer;
- (b) 4% to 12% by weight of a resorcinol formaldehyde resin prepolymer;
- and
- (c) 28% to 56% water.
A method of preparing a treating solution suitable for treating wood and other cellulose-based materials comprising:
- (a) a first step of adding phenol to a first reaction vessel;
- (b) a second step of adding formaldehyde to said first reaction vessel in a mole ratio of approximately 1.0 to 2.75 moles per mole of phenol;
- (c) a third step of adding a catalyst to said first reaction vessel in a mole ratio of 0.02 to 1.2 moles per mole of phenol, wherein said catalyst is selected from the group consisting of alkaline earth hydroxides and alkaline earth carbonates;
- (d) a fourth step of adding water to said first reaction vessel;
- (e) a fifth step of reacting the contents of said first reaction vessel for approximately 0.05 to 6 hours at a reaction temperature of 50.degree. C. to 100.degree. C. to form a phenolic resin prepolymer;
- (f) a sixth step of adjusting the solids content of the contents of said phenolic resin prepolymer with water to about 50% to 70%;
- (g) a seventh step of adding resorcinol to a second reaction vessel;
- (h) an eighth step of adding formaldehyde to said second reaction vessel in a mole ratio not exceeding 0.70 moles per mole of resorcinol;
- (i) a ninth step of adding a catalyst to said second reaction vessel in a mole ratio of 0.02 to 1.2 moles per mole of resorcinol, wherein said catalyst is selected from the group consisting of alkaline earth hydroxides and alkaline earth carbonates;
- (j) a tenth step of adding water to said second reaction vessel;
- (k) an eleventh step of reacting the contents of said second reaction vessel for approximately 0.5 to 6 hours at a reaction temperature of 50.degree. C. to 100.degree. C. to form a resorcinol formaldehyde resin prepolymer;
- (l) a twelfth step of adjusting the solids content of the contents of said resorcinol formaldehyde resin prepolymer with water to about 50% to 75%;
- (m) a thirteenth step of blending said phenolic resin prepolymer with said resorcinol formaldehyde resin prepolymer and water wherein said resorcinol formaldehyde resin prepolymer is present in a ratio of about 10% to 30% by weight of said phenolic resin prepolymer to form said treating solution.
Dependencies are inferred from the claim text.