Isıl işlemli ahşap malzemelerin yüzey renk özelliklerine farklı ahşap verniklerinin etkisi

Abstract

Özet: Bu çalışmada, ısıl işlemli ahşapların yüzey renk özelliklerine farklı ahşap verniklerinin etkisi araştırılmıştır. Doğu kayını (Fagus oriantalis L.) ve sarıçam (Pinus sylvestris L.) odunundan hazırlanmış örneklere 190, 200 ve 210 °C sıcaklıkta 2 saat süresince ısıl işlem uygulanmıştır. Daha sonra örnek yüzeyleri selülozik (SZ), sentetik (ST), poliüretan (PU) ve su bazlı (SB) ahşap vernikleri ile kaplanmıştır. Örneklerin renk özellikleri üç boyutlu CIEL*a*b* renk uzayına göre belirlenmiştir. Araştırma sonuçlarına göre, ısıl işlem sonrası işlem sıcaklığına bağlı olarak örneklerde L* değeri %64, b* değeri %70 oranında azalmıştır. a* değeri ise sarıçam örneklerde %96’ya kadar artarken, kayın örneklerde %56 oranına kadar azalmıştır. Isıl işlemli örneklerin renk değerleri vernik uygulamalarından sonra önemli derecede değişmiştir. Verniksiz örneklere göre tüm örneklerin L* değeri azalmış ve örnekler daha da koyulaşmıştır. Vernikleme sonrası, ısıl işlemli sarıçam örneklerin a* değeri önemli oranda artarken, yüksek sıcaklıkta (200 ve 210 °C) ısıl işlemli kayın örneklerde genellikle azalmıştır. b* değeri ise PU ve ST vernik uygulanmış her iki ağaç türünde önemli oranda azalmıştır. Verniklenmiş örneklerdeki toplam renk değişimi (ΔE*) değeri genel olarak 200 °C’de ısıl işlemli örneklerde daha yüksektir. Ayrıca, renk değişiminde ST vernik en fazla etkiye sahip iken, SB vernik en az etkiye sahiptir. Isıl işlem sonrası kayın ve sarıçam odunlarında elde edilen ahşap renginin maksimum düzeyde korunması arzu ediliyor ise SB vernikler tercih edilebilir.

Anahtar kelimeler: Ahşap malzeme, ısıl işlem, vernik, renk değişimi

Received (Geliş): 23.03.2017 - Revised (Düzeltme): 08.06.2017 -   Accepted (Kabul): 19.06.2017

Cite (Atıf): Pelit, H., 2017. The effect of different wood varnishes on surface color properties of heat treated wood materials. Journal of the Faculty of Forestry Istanbul University 67(2): 355-367. DOI: 10.17099/jffiu.300010

Keywords

• Ahşap malzeme,Isıl işlem,Vernik,Renk değişimi

The effect of different wood varnishes on surface color properties of heat treated wood materials

Abstract

Abstract: This study investigates the effects of different wood varnishes on the surface color properties of heat treated wood. Samples prepared from Oriental beech (Fagus orientalis L.) and Scots pine (Pinus sylvestris L.) are subjected to heat treatment at 190, 200, and 210 ° C for 2 h. Sample surfaces are then covered with cellulosic (SZ), synthetic (ST), polyurethane (PU), and water-based (SB) wood varnishes, and the color properties of samples are determined according to the three-dimensional CIEL*a*b* color space. Results show a decrease in the L* and b* values of samples by 64% and 70%, respectively, depending on the process temperature after heat treatment. The a* value increases by up to 96% for Scots pine samples and up to 56% for beech samples. Color values of heat treated samples change significantly after varnish is applied; L* values of all samples are reduced compared to unvarnished samples and samples are seen to darken. However, the a* value of heat treated Scots pine samples increases significantly after varnishing, while that of heat-treated beech samples at high temperatures (200 and 210 °C) generally decreases. Nevertheless, the b* value decreases significantly in both wood species subjected to application of PU and ST varnishes, and the total color change (ΔE*) of varnished specimens is generally higher for samples heat-treated at 200 °C. Results show that ST varnish has the largest effect on color change and SB varnish has the smallest effect. The use of SB varnishes is thus preferable when it is necessary to preserve the color of samples from either species following heat treatment.

Keywords: Wood material, heat treatment, varnish type, color change

Received (Geliş): 23.03.2017 - Revised (Düzeltme): 08.06.2017 -   Accepted (Kabul): 19.06.2017

Cite (Atıf): Pelit, H., 2017. The effect of different wood varnishes on surface color properties of heat treated wood materials. Journal of the Faculty of Forestry Istanbul University 67(2): 355-367. DOI: 10.17099/jffiu.300010

Keywords

• Wood material,Heat treatment,Varnish type,Color change

References

1. Akgül, M., Korkut, S., 2012. The effect of heat treatment on some chemical properties and colour in Scots pine and Uludağ fir wood. African Journal of Biotechnology 7(21): 2854-2859.
2. Aksoy, A., Deveci, M., Baysal, E., Toker, H., 2011. Colour and gloss changes of Scots pine after heat modification. Wood Research 56(3): 329-336.
3. ASTM D2244-15a, 2015. Standard Practice for Calculation of Color Tolerances and Color Differences From Instrumentally measured color coordinates. American Society for Testing and Materials, USA.
4. ASTM D3023-98, 2011. Standard Practice for Determination of Resistance of Factory-Applied Coatings on Wood Products to Stains and Reagents. American Society for Testing and Materials, USA.
5. Ayadi, N., Lejeune, F., Charrier, F., Charrier, B., Merlin, A., 2003. Color stability of heat-treated wood during artificial weathering. Holz als Roh-und Werkstoff 61(3): 221-226.
6. Aydemir, D., Gündüz, G., 2009. The effect of heat treatment on physical, chemical, mechanical and biological properties of wood. Journal of The Bartın Faculty of Forestry 11(15): 71-81 [Turkish].
7. Aydemir, D., Gündüz, G., Altuntaş, E., Ertas, M., Şahin, H.T., Alma, M.H., 2011. Investigating changes in the chemical constituents and dimensional stability of heat-treated hornbeam and Uludağ fir wood. BioResources 6(2): 1308-1321.
8. Baysal, E., Kart, S., Toker, H., Degirmentepe, S., 2014. Some physical characteristics of thermally treated Oriental beech wood. Maderas Ciencia y Tecnologia 16(3): 291-298.

9. Bekhta, P., Niemz, P., 2003. Effect of high temperature on the change in color, dimensional stability and mechanical properties of spruce wood. Holzforschung 57: 539-546.
10. Bekhta, P., Proszyk, S., Krystofiak, T., 2014. Colour in short-term thermo-mechanically densified veneer of various wood species. European Journal of Wood and Wood Products 72(6): 785-797.
11. Boonstra, M.J., 2008. A Two-Stage Thermal Modification of Wood, Ph.D. Thesis, Co-supervised by Ghent University, Ghent, Belgium, and Université Henry Poincaré, Nancy, France.
12. Esteves, B.M., Pereira, H.M. 2009. Wood modification by heat treatment: A review. BioResources 4(1): 370-404.
13. González-Peña, M.M., Hale, M.D., 2009. Colour in thermally modified wood of beech, Norway spruce and Scots pine. Part 1: Colour evolution and colour changes. Holzforschung 63(4): 385-393.
14. Gündüz, G., Aydemir, D., 2009. Some physical properties of heat-treated Hornbeam (Carpinus betulus) wood. Drying Technology 27(5): 714-720.
15. Gündüz, G., Aydemir, D., Korkut, S., 2010. The effect of heat treatment on some mechanical properties and color changes of Uludağ fir wood, Drying Technology 28(2): 249-255.
16. Hill Callum, A.S., 2006. Wood modification, Chemical, Thermal and other Processes. Wiley series renewable resources. School of agricultural and forest sciences, University of Wales, Bangor,
17. Huang, X., Kocaefe, D., Kocaefe, Y., Boluk, Y., Pichette, A., 2012. A spectrocolorimetric and chemical study on color modification of heat-treated wood during artificial weathering. Appl Surf Sci 258(14): 5360–5369
18. Johnson, R., 1997. Waterborne coatings, an overview of waterborne coatings: A formulator’s perspective". Journal of Coatings Technology 69: 117-121.
19. Kamdem, D.P., Pizzi, A., Jermannaud, A., 2002. Durability of heat treated wood. Holz als Roh -und Werkstoff 60(1): 1-6.
20. Kamperidou, V., Barboutis, I., Vasileiou, V., 2012. Wood is good: With knowledge and technology to a competitive forestry and wood technology sector. In: Proceedings of the 23rd International Scientific Conference, Zagreb, Croatia, 12th October 2012 Zagreb: Faculty of Forestry, University of Zagreb, pp 59-67.
21. Kocaefe, D., Poncsak, S., Boluk, Y., 2008. Effect of thermal treatment on the chemical composition and mechanical properties of birch and aspen. BioResources 3(2): 517-537. Kocaefe, D., Huang, X., Kocaefe, Y., 2015. Dimensional stabilization of wood. Current Forestry Reports 1(3): 151-161.
22. Korkut, S., Kök, M.S., Korkut, D.S., Gürleyen, T., 2008. The effects of heat treatment on technological properties in red-bud maple (Acer trautvetteri Medw.) wood. Bioresource Technology 99(6): 1538-1543.
23. Kurtoğlu, A., 2000. Wood material surface treatments, 1st edn. Istanbul University Faculty of Forestry, Istanbul [Turkish].
24. Lekounougou, S., Kocaefe, D., 2014. Durability of thermally modified Pinus banksiana (Jack pine) wood against brown and white rot fungi. International Wood Products Journal 5(2): 92-97.
25. Mayes, D., Oksanen, O., 2002. Thermowood Handbook. Finnforest, Finland.
26. Mıdıroğlu, M., 2015. Examining the varnish effects of heat treated wooden panels of picea orientalis. M.Sc. Thesis, Düzce University, Institute of Science and Technology, Düzce [Turkish].
27. Militz, H., 2002. Heat treatment of wood: European processes and their background, In: International Research Group Wood Pre, Section 4-Processes, Nº IRG/WP 02-40241.
28. Mitani, A., Barboutis, I., 2014. Changes caused by heat treatment in colour and dimensional stability of beech (Fagus sylvatica L.) wood. Drvna Ind 65(3): 225-232.
29. Mitsui, K., Murata, A., Kohara, M., Tsuchikawa, S., 2003. Colour modification of wood by light-irradiation and heat treatment,”In: Abstracts of the First European Conference on Wood Modification, Belgium.
30. Mononen, K., Alvila, L., Pakkanen, T.T., 2002. CIEL*a*b* measurements to determine the role of felling season, log storage and kiln drying on coloration of Silver birch wood. Scand J Forest Res 17: 179–191.
31. Özçifçi A., Altun S., Yapıcı F., 2009. Effects of heat treatment on technological properties of wood, In. 5th International Advanced Technologies Symposium (IATS’09), Karabük, 1171-1175 [Turkish].
32. Pelit, H., Sönmez, A., Budakçı, M., 2014. Effects of ThermoWood® process combined with thermo-mechanical densification on some physical properties of Scots pine (Pinus sylvestris L.). BioResources 9(3): 4552-4567.
33. Poncsak, S., Kocaefe, D., Bouzara, M., Pichette, A., 2006. Effect of high temperature treatment on the mechanical properties of birch (Betula pendula). Wood Science and Technology 40(8): 647-663.
34. Rowell, R.M., (ed) 2012. Handbook of wood chemistry and wood composites. CRC Press, Boca Raton
35. Sandberg, D., Haller, P., Navi, P., 2013. Thermo-hydro and thermo-hydro-mechanical wood processing - An opportunity for future environmentally friendly wood products. Wood Material Science and Engineering 8(1): 64-88.
36. Sundqvist, B., Karlsson, O., Westermark, U., 2006. Determination of formic-acid and acetic acid concentrations formed during hydrothermal treatment of birch wood and its relation to colour, strength and hardness. Wood Science and Technology 40(7): 549-561.
37. Söğütlü, C., Sönmez, A., 2006. Color changing effect of UV rays on some local wood species treated with various shielding agents. Gazi University Journal of the Faulty of Architecture and Engineering 21(1): 151-159.
38. Sönmez, A., 1997. Color changing effects of varnishes on wood surfaces”, 11th World Forestry Congress, 36, 13-22 October, Antalya, Turkey.
39. Sönmez, A., Budakçı, M., 2004. Protective layers and paint/varnish systems, finishing on woodworking II., Gazi University, Technical Education Faculty, Sevgi Ofset, Ankara [Turkish].
40. Sönmez, A., 2005. Preparation and coloring, finishing on woodworking I, Gazi University, Technical Education Faculty, Cem Web Ofset, Ankara [Turkish].
41. Şahin, H.T., Korkut S., 2016. Surface colour changes of turkish hazelnut wood caused by heat treatment. Journal of Advances in Biology & Biotechnology 6(1): 1-7.
42. Tjeerdsma, B., Militz, H., 2005. Chemical changes in hydrothermal treated wood: FTIR analysis of combined hydrothermal and dry heat-treated wood. Holz als Roh- und Werkstoff 63(2): 102-111.
43. Toker, H., Baysal, E., Kötekli, M., Türkoğlu, T.T., Kart, S., Şen, T.F., Peker, T.H., 2016. Surface characteristics of oriental beech and scots pine woods heat-treated above 200 °C. Wood Research 61(1): 43-54.
44. TS 2471, 1976. Determination of moisture content for physical and mechanical tests in wood. Turkish Standards Institution, Ankara [Turkish].
45. Tümen, İ., Aydemir, D., Gündüz, G., Üner, B., Çetin, H., 2010. Changes in the chemical structure of thermally treated wood. BioResources 5(3): 1936-1944.
46. Yalınkılıç, A.C., 2013. Determination and development of convenience of heat treated wood material in furniture production. Ph.D. Thesis, Gazi University, Institute of Science and Technology, Ankara [Turkish].
47. Yang, H., Yan, R., Chen, H., Lee, H.D., Zheng, C., 2007. Characteristics of hemicelluloses, cellulose and lignin pyrolysis. Fuel 86(12): 1781-1788.
48. Yıldız, E., 1999. Water based paint and coatings expectations and water based polyurethane bonding systems, Tübitak [Turkish].
49. Yıldız, S., Gezer, E.D., Yıdız, Ü.C., 2006. Mechanical and chemical behavior of spruce wood modified by heat. Building & Environment 41(12): 1762-1766.
50. Yılgör, N., 1999. Effects of temperature on chemical composition of wood (Sıcaklığın odunun kimyasal bileşenleri üzerine etkileri). Journal of the Faculty of Forestry Istanbul University 49(B1-2-3-4): 77-82.