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US-12624249-B2 - Wood coating compositions

US12624249B2US 12624249 B2US12624249 B2US 12624249B2US-12624249-B2

Abstract

The present invention relates to an improved wood coating composition wherein said composition (C) comprises, relative to the total weight of composition (C), from 58.00 to 95.00 weight percentage of at least one alkyd resin or at least one drying oil, from 0.10 to 8.00 wt. % of at least one microcrystalline wax having a congealing point from 60° C. to 100° C., and from 5.00 to 34.00 wt. % of at least one synthetic micronized wax, said at least one synthetic micronized wax having a particle size D 90 equal to or less than 36.0 μm and a particle size D 50 equal to or less than 20.0 μm, wherein the congealing point of the microcrystalline wax (W c ) is measured according to the standard ASTM D938, and wherein the particle size of the at least one micronized wax (M p ) is measured according to the standard DIN ISO 13320.

Inventors

  • Arne VERDUYN
  • Elke DE MEYER
  • Jan TORFS
  • Sam VAN DER HEIJDEN

Assignees

  • MUYLLE-FACON

Dates

Publication Date
20260512
Application Date
20211222
Priority Date
20210730

Claims (20)

  1. 1 . A wood coating composition comprising, relative to the total weight of the composition (C): from 58.00 to 95.00 weight percentage of at least one alkyd resin or at least one drying oil; from 0.10 to 8.00 wt. % of at least one microcrystalline wax derived from de-oiling petrolatum during the refining process of crude petroleum and having a congealing point from 60° C. to 100° C.; from 5.00 to 34.00 wt. % of at least one synthetic micronized wax selected from the group consisting of micronized polytetrafluoroethylene wax, micronized hybrid wax of polyethylene-polytetrafluoroethylene wax, micronized Fischer-Tropsch wax, micronized polyethylene wax, micronized polypropylene wax, micronized polyamide wax, and micronized polymer hybrids thereof, said at least one synthetic micronized wax having a particle size D 90 equal to or less than 36.0 μm and a particle size D 50 equal to or less than 20.0 μm [micronized wax (M p ), herein after]; wherein the congealing point of the microcrystalline wax (W c ) is measured according to the standard ASTM D938, and wherein the particle size of the at least one micronized wax (M p ) is measured according to the standard DIN ISO 13320.
  2. 2 . The composition (C) according to claim 1 , wherein the composition (C) comprises from 58.00 to 95.00 wt. %, relative to the total weight of the composition (C), of the at least one drying oil, and wherein the at least one drying oil is selected from the group consisting of linseed oil, sunflower oil, tung oil, safflower oil, soybean oil, poppy seed oil, tall oil, peanut oil, (dehydrated) castor oil, corn oil, rapeseed oil, sesame seed oil, rice germ oil, cottonseed oil, fish oil, herring oil, grape seed oil, flaxseed oil, chia oil, oiticica oil, menhaden oil, walnut oil, camelina oil, hemp seed oil, and perilla oil.
  3. 3 . The composition (C) according to claim 1 , wherein the at least one drying oil, relative to the total weight of the composition (C), is present in an amount from 65.00 to 92.00 wt. %.
  4. 4 . The composition (C) according to claim 1 , wherein the at least one drying oil, relative to the total weight of the composition (C), is present in an amount from 70.00 to 90.00 wt. %.
  5. 5 . The composition (C) according to claim 1 , wherein the microcrystalline wax (W c ) has a congealing point from 75° C. to 92° C.
  6. 6 . The composition (C) according to claim 1 , wherein the microcrystalline wax (W c ), relative to the total weight of the composition (C), is present in an amount from 0.15 to 6.00 wt. %.
  7. 7 . The composition (C) according to claim 1 , wherein the microcrystalline wax (W c ), relative to the total weight of the composition (C), is present in an amount from 0.15 to 5.00 wt. %.
  8. 8 . The composition (C) according to claim 1 , wherein the microcrystalline wax (W c ), relative to the total weight of the composition (C), is present in an amount from 0.20 to 4.00 wt. %.
  9. 9 . The composition (C) according to claim 1 , wherein the microcrystalline wax (W c ), relative to the total weight of the composition (C), is present in an amount from 0.20 to 3.00 wt. %.
  10. 10 . The composition (C) according to claim 1 , wherein the microcrystalline wax (W c ), relative to the total weight of the composition (C), is present in an amount from 0.25 to 2.00 wt. %.
  11. 11 . The composition (C) according to claim 1 , wherein the micronized wax (M p ) has a particle size D 90 equal to or less than 25.0 μm and a particle size D 50 equal to or less than 14.0 μm.
  12. 12 . The composition (C) according to claim 1 , wherein the micronized wax (M p ) has a particle size distribution: D 10 ≤3.0 μm and D 90 ≤25.0 μm and D 50 ≤14.0 μm.
  13. 13 . The composition (C) according to claim 1 , wherein the micronized wax (M p ) is selected from the group consisting of polyethylene-polytetrafluoroethylene wax, micronized Fischer-Tropsch wax, micronized polyethylene wax, and micronized polypropylene wax, and micronized polymer hybrids thereof.
  14. 14 . The composition (C) according to claim 1 , wherein the micronized wax (M p ), relative to the total weight of the composition (C), is present in an amount from 5.00 to 25.00 wt. %.
  15. 15 . A method for the manufacturing of the composition (C), according to claim 1 , wherein the method comprises the steps of intimate admixing: from 58.00 to 95.00 wt. % of at least one alkyd resin or at least one drying oil; from 0.10 to 8.00 wt. % of at least one microcrystalline wax derived from de-oiling petrolatum during the refining process of crude petroleum and having a congealing point from 60° C. to 100° C.; from 5.00 to 34.00 wt. % of at least one synthetic micronized wax selected from the group consisting of micronized polytetrafluoroethylene wax, micronized hybrid wax of polyethylene-polytetrafluoroethylene wax, micronized Fischer-Tropsch wax, micronized polyethylene wax, micronized polypropylene wax, micronized polyamide wax, and micronized polymer hybrids thereof, said at least one synthetic micronized wax having a particle size D 90 equal to or less than 36.0 μm and a particle size D 50 equal to or less than 20.0 μm; wherein all wt. % are relative to the total weight of the composition (C), wherein the congealing point of the microcrystalline wax (W c ) is measured according to the standard ASTM D938, wherein the particle size of the micronized wax (M p ) is measured according to the standard DIN ISO 13320, wherein the intimate admixing of the microcrystalline wax (W c ) is carried out at a temperature equal to or greater than the congealing point of said microcrystalline wax (W c ), and wherein the intimate admixing of the micronized wax (M p ) is carried out at a temperature lower than the melting point of said micronized wax (M p ).
  16. 16 . The method according to claim 15 , wherein the microcrystalline wax (W c ) is first mixed in at least part of the at least one alkyd resin or the at least one drying oil thereby forming a first premix, whereby said first premix is then further mixed with the micronized wax (M p ), optionally said micronized (M p ) wax being first dispersed in at least another part of the at least one alkyd resin or the at least one drying oil thereby forming a second premix, and optionally the remaining part of the at least one alkyd resin or the at least one drying oil.
  17. 17 . A method for treating a surface or at least part of a surface of a wood product wherein said wood product is treated with the composition (C), according to claim 1 , and wherein the composition (C) is applied to the surface of at least part of the surface of the wood product by painting, spraying such as air-atomized spraying, air-assisted spraying and airless spraying, flow-coating, transfer-coating, roller coating, brushing, impregnating, dipping, spreading, curtain coating.
  18. 18 . The method according to claim 17 , wherein the wood product is selected from the group consisting of decking, siding, siding cladding, roof shingles, furniture, veneer, flooring, particle board (PB), hardboard, plywood, oriented strand board (OSB), flake board, chipboard, fibreboard, medium density fibreboard (MDF), and high density fibreboard (HDF).
  19. 19 . The method according to claim 17 , wherein the composition (C) is applied to the surface or at least part of the surface of the wood product in an amount from 8.0 gram per square meter to 40.0 g/m 2 .
  20. 20 . The method according to claim 17 , wherein, prior to application, the composition (C) is first mixed with at least one accelerator.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a U.S. National Phase Patent Application and claims priority to and the benefit of International Patent Application No. PCT/EP2021/087384, filed on Dec. 22, 2021, which claims priority to Belgian Patent Application No. 2021/5606, filed on Jul. 30, 2021, and European Patent Application No. 20217130.2, filed on Dec. 23, 2020. The entire contents of each of which are incorporated herein by reference. FIELD OF THE INVENTION The present invention relates to wood coating compositions for the preservation and the protection of wood products, said wood coating compositions providing a high stability against phase separation, and an excellent spreadability, while maintaining good hardness, abrasion resistance, scratch resistance, matting, antiblocking, water repellency, and slip resistance properties. The invention further relates to methods for manufacturing of the same, to methods for treating wood products wherein said wood products are treated with the wood coating compositions, and to coated layers obtained by said methods for treating wood products wherein said wood products are treated with the wood coating compositions. BACKGROUND OF THE INVENTION Wood, as a natural hybrid composite material made of biopolymers such as cellulose, lignin and hemicelluloses, represents a versatile and widely exploited renewable resource for indoor and outdoor applications such as building, construction, and living. It has been used by mankind since thousands of years. Even today wooden furniture, floorings and articles of daily use experience great popularity. Wood provides high versatility and stability in combination with excellent workability, but, on the other hand, wood is sensitive to external influences such as abrasion, humidity, temperature variations, or germs. For instance, solid hardwood flooring and engineered wood flooring have long been a highly desirable house feature in the sense of warmth, tradition, and durability. However, hardwood floors are particularly prone to damage from accumulated foot traffic, wear and tear, and moisture. Therefore, for many years, wood coating compositions are applied to hardwood floors in order to preserve and protect the wood from deterioration, scratches, spills and stains, moisture, and the wear and tear caused by foot traffic, while maximizing, when desired, the appearance of the hardwood floors. Nowadays, many different wood coating compositions for solid hardwood floorings and engineered wood floorings exist, each of those wood coating compositions thereby demonstrating one or more of the properties such as water repellency, abrasion resistance, scratch resistance, matting, antiblocking, and slip resistance. Whereupon each wood coating has to meet individual requirements depending on the use of the wood product. This confronts wood coating formulators consistently with new challenges. Examples of coating compositions for coating materials are for instance described in US 2003/0154885 A1. US 2003/0154885 A1 generally describes the use of mixtures of waxes for coatings. These wax mixtures comprise homopolymers or copolymers of C2-C18 α-olefins, and at least another wax which can be selected from a large variety of waxes such as polyethylene waxes, polytetrafluoroethylene waxes, polypropylene waxes, amide waxes, Fischer-Tropsch paraffines, montan waxes, natural waxes, macrocrystalline paraffines and microcrystalline waxes, and the like. The wax mixtures are preferably used in micronized form as illustrated in the working examples (D50=8 μm) in which 2% by weight of some micronized wax mixtures were incorporated into an alkyd resin varnish with the aid of a dissolver for the purpose of assessing the blocking properties and the feel. US 2007/0037001 A1 discloses oil/wax coating compositions which provide good water resistance and dimensional stability to wood and wood products. The oil component may be drying oils, non-drying oils, low boiling oils, and high boiling oils. In the working examples use is made of linseed oil alone or in combination with mineral oil. A large variety of waxes are mentioned to be suitable for use. In the working examples only a paraffin wax was used. It is known that wax is widely used to provide water repellency and dimensional stability to wood and wood products. US 2007/0037001 A1, demonstrates that both water repellency and dimensional stability of wood improve upon treatment with these oil/wax coating compositions. EP 1217051 A2 describes surface treating agents for ligneous floorings that render the surface of treated floors resistant to slipping, thereby preventing tumbling. The surface treating agents contain 75-90% by weight of a plant drying oil, such as for instance linseed oil or tung oil, and 1-5% by weight of a natural and powdered carnauba wax having an average particle size equal to or less than 300 μm, for instance an average particle size of 100 μm in the working examples, fo