Journal of the Korean Wood Science and Technology

The Korean Society of Wood Science & Technology (한국목재공학회)
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Control of Discoloration of Cedar Wood (Cryptomeria japonica) by Heat and UV Treatment

열처리와 자외선처리를 이용한 삼나무 재색제어

  • Yoon, Kyung-Jin (Forest Sciences, Research Institute for Agriculture and Life Sciences, Seoul National Univ.) ;
  • Eom, Chang-Deuk (Forest Sciences, Research Institute for Agriculture and Life Sciences, Seoul National Univ.) ;
  • Park, Jun-Ho (Forest Sciences, Research Institute for Agriculture and Life Sciences, Seoul National Univ.) ;
  • Lee, Yang-Woo (Forestry Association of Seogwipo) ;
  • Choi, In-Gyu (Forest Sciences, Research Institute for Agriculture and Life Sciences, Seoul National Univ.) ;
  • Lee, Jun-Jae (Forest Sciences, Research Institute for Agriculture and Life Sciences, Seoul National Univ.) ;
  • Yeo, Hwanmyeong (Forest Sciences, Research Institute for Agriculture and Life Sciences, Seoul National Univ.)
  • Received : 2008.07.14
  • Accepted : 2008.08.04
  • Published : 2008.11.25
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Abstract

Normally, cedar heartwood has a red color. However, it frequently changes black color (blackening phenomenon). It is reported that blackening phenomenon of cedar has been caused by oxidation of phenolics and norlignan extractives under weak alkaline conditions. In this study, heat treatment and UV irradiation were carried out to reduce the difference of color value between blackened wood and bright sap wood. Effects of temperature, moisture content, treatment time and light on decrease of color difference between blackened heartwood and sapwood were evaluated in each treatment. A decrement of different color value between blackened heartwood and bright sapwood by hot-water treatment was bigger than others. An effect of the vacuum drying was similar to that of the kiln drying. UV irradiation decreases the color difference between dried blackened heartwood and bright sapwood. It is suggested that UV irradiation could be used as final treatment to reduce the color difference on wood during drying process. Determination of optimum conditions and development of hybrid process for control of discoloration will be needed in a further study.

삼나무의 심재 부위에는 흑화현상이 자주 발생한다. 심재 내 페놀성 추출물과 Norlignans 물질이 약알칼리하에서 산화함으로써 흑화현상이 발생한다고 보고된 바 있다. 본 연구에서는 삼나무 내부 흑심재와 변재간의 색상차를 줄여보고자 열처리와 광처리를 실시하였다. 열처리로는 열기건조, 진공가열건조, 열수처리를 적용하였고, 광처리로는 삼나무 표면에 자외선광을 조사하였다. 열처리와 광처리에서 온도와 함수율 및 자외선의 색상차 감소효과를 평가하였다. 색상차 감소 효과는 열수처리가 가장 우수하였으며, 산소량이 적은 저기압 상태에서 건조시킴으로써 산화반응을 줄여보고자 실시한 진공건조는 기대한 바와 달리 열기건조와 비슷한 정도의 목재 표면의 색상차 감소효과를 보였다. 광처리는 건조재 표면의 색상차 감소효과를 보여 대패가공 후 마감처리에 적합한 것으로 판단된다. 추후 효과적인 삼나무 재색제어를 위해서 각 처리별 최적 공정조건 탐색 및 복합처리 적용기술개발이 필요하다.

Keywords

References

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