Color and Color Uniformity Variation of Scots Pine Wood in the Air-Dry Condition

Authors

  • Mika Grekin

Keywords:

CIE <i>L*a*b*</i>, linear mixed models, <i>Pinus sylvestris</i>

Abstract

Appearance has an important influence on people's impression and valuation of wood products. One of the major factors that affects the appearance of wooden surfaces made of pine is the simultaneous presence of sapwood and heartwood as these components can vary considerably in color, and large differences between them can affect value and end-uses. In this paper, the color of Scots pine wood in the air-dry condition is discussed in terms of CIE L*a*b* color parameters and calculated color uniformity parameters between heartwood and sapwood from samples collected from stands in five geographical regions in Finland and Sweden. The background of the differences in color parameters is also discussed. There were significant differences in color parameters between heartwood and sapwood; in addition, geographical origin and sampling height within a tree had significant effects on color of both heartwood and sapwood. Some differences were also found between regions and heights in the color uniformity parameters. However, concerning the practical applications, the results should be considered as indicative due to several departures from conventional practices.

References

Andtbacka, A., B. Holmbom, and J. S. Gratzl. 1989. Factors influencing light-induced yellowing and bleaching of spruce groundwood. Pages 347-351 in Proc. 5th International Symposium on Wood and Pulping Chemistry (ISWPC), May 22-25, 1989, Raleigh, NC.nBroman, N. O. 2000. Means to measure the aesthetic properties of wood. Doctoral Thesis, Luleå University of Technology, Division of Wood Technology, Luleå, Sweden.nEk, M. 1992. Some aspects on the mechanism of photoyellowing of high-yield pulps. Doctoral Thesis, Royal Institute of Technology (KTH), Stockholm, Sweden.nEnglund, F., and R. M. Nussbaum. 2000. Monoterpenes in Scots pine and Norway spruce and their emission during kiln drying. Holzforschung54(5):449-456.nFengel, D. 1969. The ultrastructure of cellulose from wood. Part 1: Wood as the basic material for the isolation of cellulose. Wood Sci. Technol.3(3):203-217.nFengel, D., and G. Wegener. 1984. Wood. Chemistry, ultrastructure and reactions. De Gruyter, Berlin, Germany. 613 pp.nFukazawa, K., and H. Imagawa. 1981. Quantitative analysis of lignin using an UV microscopic image analyser. Variation within one growth increment. Wood Sci. Technol.15(1):45-55.nGierlinger, N., D. Jacques, M. Grabner, R. Wimmer, M. Schwanninger, P. Rozenberg, and L. E. Pâques. 2004. Colour of larch heartwood and relationships to extractives and brown-rot decay resistance. Trees18(1):102-108.nGrekin, M. 2006. Amount of total phenolic compounds in Scots pine wood from Finland and Sweden. Unpublished data.nHakkila, P. 1968. Geographical variation of some properties of pine and spruce pulpwood in Finland. Commun. Inst. For. Fenn.66(8):1-60.nHakkila, P., H. Kalaja, and P. Saranpää. 1995. Etelä-Suomen ensiharvennusmänniköt kuitu-ja energialähteenä. [First thinning pine stands as a source of pulpwood and energy in southern Finland.] Finnish Forest Research Institute, Research Papers 582. 100 pp. In Finnish.nHarju, A., M. Venäläinen, and M. Grekin. 2006. Dependence of colour change due to UV light on the extractive content in Scots pine heartwood. Unpublished manuscript.nHildebrandt, G. 1960. The effect of growth conditions on the structure and properties of wood. Pages 1348-1353 in Proc. 5th World Forestry Congress, August 29-September 10, 1960, Seattle, WA.nHinterstoisser, B., R. Jalkanen, and M. Schwanninger. 2001. Lignification of Scots pine trees from Arctic Circle up to timberline. Búvísindi14:55-59.nHon, D. N. S. 1979. Photooxidative degradation of cellulose: Reactions of the cellulosic free radicals with oxygen. J. Polym. Sci. Pol. Chem.17(2):441-454.nHon, D. N. S., and W. Glasser. 1979. On possible chromophoric structures in wood and pulps. Polym.-Plast. Technol.12: 159-179.nHu, T. Q., G. Leary, and D. Wong. 1999. A new approach towards the yellowing inhibition of mechanical pulps. Part I: Selective removal of α-hydroxyl and α-carbonyl groups in lignin model compounds. Holzforschung53(1):43-48.nHunt, R. W. G. 1998. Measuring colour. Fountain Press, Kingston-upon-Thames, England. 344 pp.nJensen, L. K., A. Larsen, L. Mølhave, M. K. Hansen, and B. Knudsen. 2001. Health evaluation of volatile organic compound (VOC) emissions from wood and wood-based materials. Arch. Environ. Health56(5):419-432.nKleinert, T. N., and L. M. Marraccini. 1966a. Aging and colour reversion of bleached pulps. The role of aldehyde end groups. Sven. Papperstidn.69:69-71.nKleinert, T. N., and L. M. Marraccini. 1966b. Aging and colour reversion of bleached pulps. Pulp extractives from air aging at high humidity. Sven. Papperstidn.69:159-160.nKärkkäinen, M. 1981. Männyn ja kuusen runkopuun pihkapitoisuuden lisääminen sivutuotesaannon kohottamiseksi. Summary: Increasing resin content in pine and spruce stemwood for higher by-product yield. Commun. Inst. For. Fenn.96(8):1-81. In Finnish with summary in English.nKärkkäinen, M. 2003. Puutieteen perusteet. [Basics of wood science.] Metsälehti Kustannus. 451 pp. In Finnish.nLarson, R. R. 1966. Changes in chemical composition of wood cell walls associated with age in Pinus resinosa. Forest Prod. J.16(4):37-45.nLeary, G. J. 1968. The yellowing of wood by light: Part II. Tappi51(6):257-260.nNakamura, M., M. Masuda, and M. Inagaki. 1993. Influences of knots and grooves on psychological images of wood wall-panels. Mokuzai Gakkaishi39(2):152-160.nKärkkäinen, M., and Y. Hiramatsu. 1994. Visual factors influencing psychological images of woods and stones. Mokuzai Gakkaishi40(4):364-371.nNimz, H. H. 1973. Chemistry of potential chromophoric groups in beech lignin. Tappi J.56(5):124-126.nNolan, P. A. 1945. The "fading" of groundwood by light. Pap. Trade J.121(23):219-223.nNurmi, J. 1993. Heating values of whole-tree biomass in young forests in Finland. Licentiate thesis, Helsinki University, Department of Forest Technology, Helsinki, Finland.nSjöström, E. 1992. Wood chemistry: Fundamentals and applications. Academic Press, New York, NY. 293 pp.nTyrväinen, J. 1995. Wood and fiber properties of Norway spruce and its suitability for thermomechanical pulping. Acta For. Fenn.249:1-155.nUpprichard, J. M. 1971. Cellulose and lignin content in Pinus radiata D. Don. Within-tree variation in chemical composition, density and tracheid length. Holzforschung25(4):97-105.nUpprichard, J. M., and J. A. Lloyd. 1980. Influence of tree age on the chemical composition of Radiata pine. New Zeal. J. For. Sci.10(3):551-557.nVoipio, R., and T. Laakso. 1992. Pienikokoisten puiden maanpäällisen biomassan kemiallinen koostumus. Summary: Chemical composition of the above ground biomass of small-sized trees. Folia For.789:1-22. In Finnish with summary in English.nYazaki, Y., P. J. Collins, and B. McCombe. 1994. Variations in hot water extractives content and density of commercial wood veneers from blackbutt (Eucalyptus pilularis). Holzforschung48 (suppl.):107-111.n

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Published

2007-09-27

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Research Contributions