Comparison of Exterior Coatings Applied to Oak Wood as a Function of Natural and Artificial Weathering Exposure
Source abstract
Abstract
Artificial weathering can significantly reduce the testing time needed for proving coating durability, nevertheless its reliability is still not thoroughly proven. In this study, eight different transparent and pigmented coating systems, namely oil, acrylate, alkyd and urethane alkyd were evaluated through natural and artificial weathering tests on oak samples by measuring colour, gloss and surface wettability and by macroscopic and microscopic evaluation. The oil coatings performed well in wood colour stability evaluations, while the best gloss and wettability change results were noted for acrylate coatings. Pigmented coatings were characterized by significantly lower colour changes than transparent ones. The gloss and wettability changes were more sensitive to coating disruption than to total colour changes of coated wood associated with chemical changes in wood. The findings in this work showed that values of gloss changes and surface wettability for all types of coatings exposed to artificial and natural weathering resulted in significant differences from each other. The data obtained by artificial weathering method provide basic results of coatings durability and, ideally, natural weathering should be performed at the same time to support the results from laboratory tests by exposing wood under real conditions.
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Research context
OpenAlex topics: Wood Treatment and Properties · Cultural Heritage Materials Analysis · Building materials and conservation
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Wood Processing and Biomaterials, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences in Prague, Kamýcká 129, 165 00 Prague, Czech Republic
Department of Natural Resource Ecology and Management, Oklahoma State University, 303-G Agricultural Hall, Stillwater, OK 74078, USA
Funding
Technology Agency of the Czech Republic
References (54)
Show source-provided references
1. EN 350 (2016). Durability of Wood and Wood-Based Products—Testing and Classification of the Durability to Biological Agents of Wood and Wood-Based Materials, European Committee for Standardization.
2. UV light impact on ellagitannins and wood surface colour of European oak (Quercus petraea and Quercus robur)10.1016/j.apsusc.2006.11.005 ↗
3. Sivrikaya, H. (2003). Impregnability and Durability Characteristics of Sapwood and Heartwood. [Ph.D. Thesis, Zonguldak Karaelmas University, Graduate School of Natural and Applied Sciences].
4. Ayadi, N. (2004). Vieillissement Climatique d’un Systéme Bois-Vernis-Absorbeur UV Inorganique. [Ph.D. Thesis, Université de Nantes].
5. Browne, F.L. (1958). Wood Properties that Affect Paint Performance.
6. The effect of natural weathering on untreated wood surface
7. Photodegradation and photostabilisation of wood—The state of the art10.1016/j.polymdegradstab.2004.10.018 ↗
8. Improvement of photoprotection of wood coatings by using inorganic nanoparticles as ultraviolet absorbers
9. Feist, W.C., and Hon, D.N.S. (1984). Chemistry of weathering and protection. The Chemistry of Solid Wood, ACS.10.1021/ba-1984-0207.ch011 ↗
10. Weathering and photoprotection of wood10.1021/bk-2008-0982.ch005 ↗
11. Cogulet, A., Blanchet, P., and Landry, V. (2019). Evaluation of the impacts of four weathering methods on two acrylic paints: Showcasing distinctions and particularities. Coatings, 9.10.3390/coatings9020121 ↗
12. Review on the durability of exterior wood coatings with reduced VOC-content10.1016/S0300-9440(01)00170-9 ↗
13. The search for durable exterior clear coatings for wood10.3390/coatings5040830 ↗
14. Microscale changes in cell structure at softwood surfaces during weathering
15. Šimůnková, K., Oberhofnerová, E., Reinprecht, L., Pánek, M., Podlena, M., and Štěrbová, I. (2019). Durability of selected transparent and semi-transparent coatings on Siberian and European larch during artificial weathering. Coatings, 9.10.3390/coatings9010039 ↗
16. Rapid prediction of surface characteristics of European and Siberian larch wood by FT-NIRS10.1007/s00107-016-1112-4 ↗
17. Modelling mould growth on coated modified and unmodified wood substrates exposed outdoors10.1007/s00226-009-0283-0 ↗
18. Outdoor weathering performance parameters of exterior wood coating systems on tropical hardwood substrates10.1007/s00107-014-0779-7 ↗
19. Biodeterioration of external architectural paint films—A review10.1016/j.ibiod.2011.09.005 ↗
20. Maintenance procedures and definition of limit states for exterior wood coatings10.1007/s00107-010-0469-z ↗
21. Enhancing exterior performance of clear coatings through photostabilization of wood. Part 2: Coating and weathering performance10.1007/s11998-008-9090-z ↗
22. Moisture dynamics and fungal susceptibility of plywood10.1016/j.ibiod.2010.12.015 ↗
23. Comparison of wood coating durability in natural weathering and artificial weathering using fluorescent UV-lamps and water10.1007/s00107-014-0791-y ↗
24. Influence of artificial and natural weathering on the hydrophobicity and surface properties of wood
25. Weathering performance of surface of thermally modified wood finished with nanoparticles-modified waterborne polyacrylate coatings10.1016/j.apsusc.2017.03.011 ↗
26. EN 927-3 (2006). Paints and Varnishes. Coating Materials and Coating System for Exterior Wood, Part 3: Natural Weathering Test, European Committee for Standardization.
27. EN 927-6 (2006). Paints and Varnishes. Coating Materials and Coating Systems for Exterior Wood, Part 6: Exposure of Wood Coatings to Artificial Weathering Using Fluorescent UV Lamps and Water, European Committee for Standardization.
28. Effects of wood roughness, light pigments, and water repellent on the color stability of painted spruce subjected to natural and accelerated weathering10.15376/biores.10.4.7203-7219 ↗
29. Comparison of organic coating accelerated tests and natural weathering considering meteorological data10.1016/j.porgcoat.2006.09.036 ↗
30. Effects of adding TiO2 nanoparticles to a water-based varnish for wood applied to nine tropical woods of Costa Rica exposed to natural and accelerated weathering10.1007/s11998-016-9848-7 ↗
31. Effect of surface pretreatment with natural essential oils on the weathering performance of spruce wood10.15376/biores.13.3.7053-7070 ↗
32. Correlation and modeling between color variation and quality of the surface between accelerated and natural tropical weathering in Acacia mangium, Cedrela odorata and Tectona grandis wood with two coating10.1002/col.21826 ↗
33. The efficiency of various treatments in protecting wood surfaces against weathering10.1007/BF02699559 ↗
34. Natural and artificial weathering characteristics of stabilized acrylic–urethane paints10.1016/j.polymdegradstab.2008.02.008 ↗
35. Wood surface discolouration due to simulated indoor sunlight exposure10.1007/s00107-007-0201-9 ↗
36. Influence of climatic factors on the weathering of coated wood10.1007/s00107-002-0338-5 ↗
37. ČSN 49 0108 (1993). Drevo. Zist’ovanie Hustoty [Wood. Determination of the Density].
38. (2019, November 27). Meteostation of the Faculty of Agronomy—Department of Agroecology and Biometeorology, Prague, Czech Republic. Available online: http://meteostanice.agrobiologie.cz.
39. Pánek, M., Oberhofnerová, E., Zeidler, A., and Šedivka, P. (2017). Efficacy of hydrophobic coatings in protecting oak wood surfaces during accelerated weathering. Coatings, 7.10.3390/coatings7100172 ↗
40. Commission Internationale de l’Eclairage (CIE) (1986). Colorimetry, Commission Internationale de l’Eclairage. [2nd ed.]. (CIE Pub. No. 15.2).
41. EN ISO 2813 (2014). Paints and Varnishes—Determination of Gloss Value at 20 Degrees, 60 Degrees and 85 Degrees, European Committee for Standardization.
42. Water uptake and wetting behaviour of furfurylated, N-methylol melamine modified and heat-treated wood10.1007/s00107-015-0919-8 ↗
43. Weathering properties of wood species treated with different coating applications10.15376/biores.7.4.4875-4888 ↗
44. Turkoglu, T., Baysal, E., and Toker, H. (2015). The effects of natural weathering on color stability of impregnated and varnished wood materials. Adv. Mater. Sci. Eng.10.1155/2015/526570 ↗
45. Sehlstedt-Persson, M. (2003, January 24–29). Color responses to heat-treatment of extractives and sap from pine and spruce. Proceedings of the 8th IUFRO International Wood Drying Conference: Improvement and Innovation in Wood Drying: A Major Issue for a Renewable Material, Brasov, Romania.
46. Studies on the loss of gloss of shellac and polyurethane finishes exposed to UV
47. Kubovský, I., Oberhofnerová, E., Kačík, F., and Pánek, M. (2018). Surface changes of selected hardwoods due to weather conditions. Forests, 9.10.3390/f9090557 ↗
48. Natural weathering of oak (Quercus petrae) and chestnut (Castanea sativa) coated with various finishes10.1002/col.20581 ↗
49. Effect of accelerated weathering on surface chemistry of modified wood10.1016/j.apsusc.2006.12.005 ↗
50. A review on natural products as wood protectant10.1007/s00226-011-0448-5 ↗
51. Colour stability and surface defects of naturally aged wood treated with transparent paints for exterior constructions
52. Critical view on the possibility of color changes prediction in the surfaces of painted wood exposed outdoors using accelerated weathering in Xenotest10.1007/s11998-018-0125-9 ↗
53. Q-LAB (2019, December 16). Correlation of Laboratory to Natural Weathering. Available online: www.q-lab.com/resources/technical-articles.aspx.
54. Colour changes of Brazilian eucalypts wood by natural weathering10.1179/2042645313Y.0000000035 ↗