COLOUR CHARACTERISTICS OF DENSIFIED AND THERMALLY POST-TREATED BEECH AND PINE WOODS

Hüseyin Pelit
1.507 365

Abstract


Effect of thermo-mechanical densification and thermal post-treatment on the colour parameters (L*, a*, b* and ΔE*) of beech (Fagus oriantalis L.) and pine (Pinus sylvestris L.) wood species were investigated. Wood specimens were densified at temperatures of 100 or 150 °C and compression ratios of 20% or 40%. Then, thermal post-treatment was applied to the specimens during 2 h at 190, 200, and 210 °C to provide dimensional stability in densified specimens. The colour change of the specimens was evaluated by CIEL*a*b* colour co-ordinate systems. The results showed that, the colour of the densified specimens at higher temperature and compression ratio was more changed. The compression temperature was more effective compared to compression ratio on the colour change of specimens. After the thermal post-treatment, colour characteristics of specimens have changed significantly depending on the increase in the treatment temperature, and specimens darkened. Densification processes has little effect on colour changes of the thermally post-treated specimens. The colour of pine specimens compared with the beech specimens more affected by the densification and thermal treatment applications. Morever, the change in a* value of specimens is more evident than the change in L* or b* values.

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References


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