TUNG OIL-BASED NON-LAPPING WATER-COMPATIBLE WOOD STAIN

Abstract

Water-based stains are based on an oil-in-water emulsion having a binder that includes, consists of, or consists essentially of drying oil combined with a non-aqueous polymer dispersion. The compositions can be tinted using traditional water-based pigment dispersions, yet the overall hydrophobicity results in minimal interaction with the polar cellulosic structure of wood.

Claims

1. A wood stain composition comprising: a binder consisting essentially of drying oil and a non-aqueous polymer dispersion.

2. The composition of claim 1, further comprising a water-based pigment dispersion.

3. The composition of claim 1, wherein the non-aqueous polymer dispersion is an alkyd dispersion.

4. The composition of claim 1, further comprising a thickener.

5. (canceled)

6. The composition of claim 1, further comprising a defoamer.

7. The composition of claim 1, further comprising an amine.

8. (canceled)

9. The composition of claim 1, further comprising at least one drying agent.

10. The composition of claim 1, further comprising a surfactant.

11. The composition of claim 10, wherein the surfactant has a hydrophile-lipophile balance value between 5 and 15.

12. The composition of claim 10, wherein the surfactant is an octylphenol ethoxylate surfactant.

13. A method of making a wood stain composition, the method comprising the steps of: forming a first mixture by combining drying oil and a non-aqueous polymer dispersion; forming a second mixture by combining water and a surfactant; adding the first mixture to the second mixture to form a third mixture, and mixing the third mixture until a smooth uniform state is achieved.

14. The method of claim 13, further comprising adding a pigment composition to the third mixture.

15. The method of claim 13, wherein the non-aqueous polymer dispersion is an alkyd dispersion.

16. The method of claim 13, wherein the second mixture further comprises a thickener.

17. (canceled)

18. The method of claim 13, wherein the second mixture further comprises a defoamer.

19. The method of claim 13, wherein the second mixture further comprises an amine.

20. (canceled)

21. The method of claim 13, wherein the first mixture further comprises at least one drying agent.

22. The method of claim 13, wherein the first mixture further comprises at least one viscosity reducing agent.

23. The method of claim 13, wherein the surfactant has a hydrophile-lipophile balance value between 5 and 15.

24. The method of claim 13, wherein the surfactant is an octylphenol ethoxylate surfactant.

Description

DETAILED DESCRIPTION

[0013] Drying oils, which consist of glycerol triesters of fatty acids, such as tong oil and linseed oil are a popular finish for wood because of their protective properties and visual appearance. When dried, the drying oils impart a satin “wetted wood” look with a slight golden tint. Because of their viscosity, drying oils may be diluted with solvent, resulting in compositions that are easily applied but which can pose environmental risks. As noted earlier, water-based drying oil staining and finishing compositions, while less environmentally problematic, can exhibit numerous performance disadvantages. Compositions in accordance herewith achieve water compatibility without sacrificing ease of application and post-application performance properties.

[0014] By itself, a binder of drying oil and a non-aqueous dispersion is not water-compatible, but formulations in accordance herewith utilize a surfactant to confer aqueous compatibility without sacrificing the benefits (in terms of application convenience and appearance) of the nonpolar drying oil.

[0015] A suitable generic formulation is as follows:

TABLE-US-00001 Component Weight % Amine 0.1%-2% Thickener 0.1%-2% Defoamer 0.1%-1% Surfactant (HLB-Value between 5-15) 0.1%-5% Pigment dispersion   2%-15% Non-aqueous alkyd dispersion 0.5%-10% Aliphatic Solvent   5%-40% Drying oil   5%-40% Metallic Driers (consisting of cobalt, 0.1%-5% calcium, magnesium, and/or zirconium)

[0016] The thickener is used to adjust the viscosity of the composition to a desired value. Suitable thickeners include hydroxyethylcellulose, hydrophobically-modified ethylene oxide-based urethanes, hydrophobically-modified alkali soluble emulsions, and/or other alkali-soluble associative thickeners. The amine, in turn, is used to activate the thickener. Suitable amines include dimethylethanolamine, monoethylethanolamine, trimethylethanolamine, morpholine, and/or ammonia. The defoamer is employed break foam generated during formula processing and/or application of the stain onto wood; suitable defoamers include deaerators such as AIREX 900, available from TEGO. All three of these components are optional. The surfactant may have a hydrophile-lipophile balance (HLB) value between 5 and 15. The other ingredients are drying agents, which are desirable to minimize time between coats or application of a finish, but can be omitted in whole or in part. Other conventional drying agents known to those skilled in the art may also or alternatively been employed. The CEM-ALL and DRI-RX HF products are available from Borchers Americas, Inc.

[0017] A representative working formulation is as follows:

TABLE-US-00002 Description Weight % Water 41.6500% Dimethylethanolamine-anhydrous 0.2000 % 300 molecular weight hydroxyethylcellulose thickener 0.2000 % TEGO AIREX 900 0.2000 % TRITON X-405 0.2500 % SUPER SEATONE burnt umber dispersion 7.0000 % 396250-NAD 4.0000 % Mineral spirits 7.400 % APS-D4 octamethylcyclotetrasiloxane 10.600 % Raw Drying Oil (Tung Oil) 24.000 % 10% calcium CEM-ALL 1.0000 % 12% cobalt drier CEM-ALL 1.0000 % 18% Zr 2-ethylhexanoate 1.0000 % DRI-RX HF 2,2′-bipyridyl solution 0.5000 % Methyl ethyl ketoxime 1.0000 %

[0018] TRITON X-405 is polyoxyethylene (40) isooctylcyclohexyl ether, a nonionic surfactant available from Sigma-Aldrich. The SUPER SEATONE burnt umber dispersion is an aqueous (water/propylene glycol) dispersion available from DyStar Singapore Pte Ltd. 396250-NAD is an alkyd non-aqueous polymer dispersion (NAD) proprietary to Sherwin Williams Company and is an optional ingredient; it serves to reduce dry time and/or water sensitivity of the stain. APS-D4 octamethylcyclotetrasiloxane is available from Advanced Polymer, Inc., and serves to reduce the viscosity of the drying oil.

[0019] Mixing is performed in a two-part process. Part 1 involves the NAD, mineral spirts, APS-D4, tung oil, and the various drier components. These are combined in a vessel and well mixed. Part 2 is carried out in a separate vessel that contains the water, amine, thickener, defoamer, and surfactant, which are mixed to a homogeneous state. At this point the Part 1 contents are slowly added to Part 2 under agitation and mixed until a smooth uniform state is achieved. The system can be then pigmented using any suitable pigment composition (most common water-based pigments dispersions can be employed) to the desired color space.

[0020] While the invention has been described in conjunction with the specific embodiments thereof, one of ordinary skill in the art will understand that any alternatives, modifications, and variations of the types of the ingredients and/or the amounts thereof contained in the single formula finish are possible and are they within the scope of the present invention.

[0021] The terms and expressions employed herein are used as terms and expressions of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described or portions thereof. In addition, having described certain embodiments of the invention, it will be apparent to those of ordinary skill in the art that other embodiments incorporating the concepts disclosed herein may be used without departing from the spirit and scope of the invention. Accordingly, the described embodiments are to be considered in all respects as only illustrative and not restrictive.