METHODS OF PREPARING POROUS WOOD PRODUCTS FOR PAINTING AND FINISHING

• US 20180127613A1
• Filed: 01/05/2018
• Published: 05/10/2018
• Est. Priority Date: 06/30/2015
• Status: Active Grant

• Current Assignee: Pressing Developments, L.L.C.
• Original Assignee: Widner Product Finishing, Inc.
• Inventors: Fuhr, Adam
• Granted Patent: US 10,400,127 B2
• Time in Patent Office: Days
• CPC Class Codes: B05D 1/02 performed by spraying
• CPC Class Codes: B05D 3/067 Curing or cross-linking the coating
• CPC Class Codes: B05D 7/06 to wood
• CPC Class Codes: B05D 7/546 each layer being cured, at least partially, separately
• CPC Class Codes: B05D 7/586 each layer being cured, at least partially, separately
• CPC Class Codes: C08F 222/102 of dialcohols, e.g. ethylene glycol di(meth)acrylate or 1,4-butanediol dimethacrylate
• CPC Class Codes: C08K 3/34 Silicon-containing compounds
• CPC Class Codes: C09D 133/14 of esters containing halogen, nitrogen, sulfur or oxygen atoms in addition to the carboxy oxygen
• CPC Class Codes: C09D 135/02 Homopolymers or copolymers of esters C09D135/06, C09D135/08 take precedence
• CPC Class Codes: C09D 15/00 Woodstains
• CPC Class Codes: C09D 4/00 Coating compositions, e.g. paints, varnishes or lacquers, based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond ; Coating compositions, based on monomers of macromolecular compounds of groups C09D183/00 - C09D183/16

Abstract

Methods of preparing porous wood products for painting or finishing are described. The methods comprise applying to a porous wood product a UV-curable coating and curing by UV light the top UV curable coating to 70% to 95% cure, preferably 85% to 95% for spray-applied top UV curable coatings to produce a partially cured porous wood product. The methods typically further include the step of sanding the surface of the partially cured porous wood product and painting or staining, for example with a water-based or solvent-based stain or paint.

Claims

1. A method of preparing a porous wood product for painting or staining to improve the quality of a finishing coat, comprising:

a. applying to the porous wood product a coat of UV-curable coating;

a. partially curing the UV-curable coating;

b. applying onto the partially cured porous wood product a top UV-curable coating; and

c. partially curing the top UV-curable coating to 80-95% cure.

2. The method of claim 1, wherein the porous wood product has one or more side portions and wherein the UV-curable coating is spray-applied to the one or more side portions.

3. The method of claim 1, wherein at least two UV-curable coatings are applied prior to applying the top UV-curable coating and the combined application weight for all UV-curable coatings is selected from the group consisting of:

28-100 g/m², 28-120 g/m², 45-120 g/m², and 45-180 g/m².

4. The method of claim 1, further comprising applying a water-based tie coat to the porous wood product prior to applying a UV-curable coating, and wherein the UV-curable coating is partially cured to 50-70% cure, and the top UV-curable coating is cured to 85-95% cure.

5. The method of claim 1, wherein the UV-curable coatings are spray-applied and comprise 10-40% filler based on the total weight of the coating compositions, with the top UV-curable coating cured to 85-95% cure.

6. The method of claim 1, wherein the UV-curable coating comprises 20-40% filler based on the total weight of the coating composition.

7. The method of claim 1, wherein the top UV-curable coatings comprises at least one filler selected from the group consisting of:

CaCO₃, silica, talc, silicone, Kaolin Clay, feldspar, titanium dioxide, and nepheline syenite.

8. The method of claim 1, wherein the UV-curable coating comprises, based on the total volume of the coating composition:

a. Amine Modified Polyether Acrylate;

25-45%;

b. Dipropylene Glycol Diacrylate;

36-60%;

c. nepheline syenite;

7-30%;

d. Feldspar;

6-30%;

e. 2-Hydroxy-2methyl-1-phenyl-1-propanone;

0.5-3%;

f. 1-hydroxy-cyclohexyl-phenyl-ketone;

0.5-3%; and

g. Benzophenone;

0.5-3%.

9. A method of preparing a porous wood product comprising:

a. applying to the porous wood product a top UV-curable coating, wherein the top UV-curable coating comprises at least one filler;

b. partially curing the top UV-curable coating to 70-95% cure; and

c. sanding the partially cured top UV-curable coat.

10. The method of claim 9, wherein the top UV-curable coating is spray-applied and the filler is selected from the group consisting of:

CaCO₃, silica, talc, silicone, Kaolin Clay, feldspar, titanium dioxide, and nepheline syenite.

11. The method of claim 9, wherein the top UV-curable coating is applied with an application weight of 65-85 g/m² if one UV-curable coat is applied;

45-65 g/m² per layer if two UV-curable coats are applied; and

35-55 g/m² per layer if three UV-curable coats are applied.

12. The method of claim 9, wherein the top UV-curable coating is partially cured to 80% to 95%.

13. The method of claim 9, further comprising the step of spray-applying between two and four UV-curable coatings, sanding each UV-curable coating after partially curing, and applying a finishing coating of paint or stain to the sanded and partially cured top UV-curable coating.

14. The method of claim 9, wherein the UV-curable coating further comprises a photoinitiator selected from the group consisting of:

0.5-3% 2-Hydroxy-2methyl-1-phenyl-1-propanone, 0.5-3% 1-hydroxy-cyclohexyl-phenyl-ketone, and 0.5-3% Benzophenone;

wherein the % of the photoinitiator is weight % based on the total volume of the coating composition.

15. The method of claim 9, wherein the UV curing energy of the top UV-curable coating is 435-583 mJ/cm².

16. The method of claim 9, wherein the top UV-curable coating comprises at least one monomer additive selected from the group consisting of:

DPGDA, HDODA, TRPDGA, TMPTA, TMPTMA, TPGDA, HDDA, and PETA.

17. The method of claim 16, wherein the top UV-curable coating comprises at least one monomer additive selected from the group consisting of:

TRPDGA, TMPTMA, and PETA.

18. The method of claim 9, wherein the UV-curable coating comprises 10-40% filler based on the total weight of the coating composition.

19. A method of preparing a porous wood product for painting or staining to improve the quality of a finishing coat, comprising:

a. applying to the porous wood product a coat of UV-curable coating;

b. partially curing the coat of UV-curable coating;

c. applying to the coated porous wood product a top UV-curable coating, wherein the top UV-curable coating comprises at least one filler selected from the group consisting of;

CaCO₃, silica, talc, silicone, Kaolin Clay, feldspar, titanium dioxide, and nepheline syenite;

d. partially curing the top UV-curable coating to 70-95%; and

e. sanding the partially cured top UV-curable coating.

20. The method of claim 19, wherein the porous wood product has one or more side portions and wherein the UV-curable coating is spray-applied to the one or more side portions and the top UV-curable coating that is spray-applied is cured to 85-95% cure.