• Journal of the Korean Wood Science and Technology
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• 제49권6호
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• pp.602-615
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• 2021

Red jabon wood is a potential fast-growing species for veneer, furniture, and many other wood products, but its durability is very low. The purpose of this study was to investigate the effects of castor bean oil and heating on boron leaching, dimensional stability, and resistance to decay fungi in treated jabon wood. Red jabon wood was preserved with boron solutions containing 5% boron (boric acid, borax, or borax-boric acid). Following that, castor bean oil impregnation and heating were used as posttreatments. Furthermore, all the wood samples were tested in terms of leaching, dimensional stability, and resistance against Schizophyllum commune and Fomitopsis palustris fungi. This study discovered that boron compounds, castor bean oil, and heating treatments influenced the leaching, dimensional stability, and resistance of red jabon wood to decay fungi. The double impregnation of boric acid or borax and castor bean oil, followed by heating at 160℃, significantly reduced water absorption and leaching while increasing the dimensional stability and resistance of red jabon wood against the two tested decay fungi.

• Journal of the Korean Wood Science and Technology
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• 제37권6호
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• pp.566-577
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• 2009

실내에서 일어나는 목재의 표면 열화특성을 재색, 화학적 및 해부학적 변화 차원에서 분석하였다. 실험대상으로는 실내에서 장기간 보관중인 삼나무 목제품을 사용하였다. 실내 보존 초기에는 황색도와 적색도가 급격히 변하였고 5년 사이에 백색도의 감소가 두드러졌다. 화학성분의 분석결과 셀룰로오스, 헤미셀룰로오스, 리그닌 성분 모두 감소하였으나 리그닌의 감소가 더 컸다. 현미경 관찰 결과 5년이 경과한 목제품에서는 목재표면에서 2~3개 층에서 리그닌이 분해되어 중간층이 분리되었다. 실내 환경조건에서 발생되는 표면 열화 특성은 야외에서 발생되는 표면열화 특성과 매우 유사하였으나 그 정도는 미약하였다.

• Journal of the Korean Wood Science and Technology
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• 제47권5호
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• pp.567-578
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• 2019

A common problem with fast-growing hardwoods is dimensional instability that limits use of their wood. In this study, we investigated the effects of pre-drying methods, temperatures, and heating duration on the specific gravity, water absorption, and dimensional stability of three tropical fast-growing hardwoods, jabon (Neolamarckia cadamba Roxb.), sengon (Falcataria moluccana Miq.), and mangium (Acacia mangium Willd.). Wood samples were pre-dried by two methods (fan and oven at $40^{\circ}C$), and heat treatments were performed at three temperatures (120, 150, and $180^{\circ}C$) for two different time periods (2 and 6 hours). The specific gravity, water absorption, dimensional stability, and structural changes of the samples were evaluated. The results revealed that heat treatments slightly reduced the specific gravity of all three wood species. In addition, the heat treatments reduced water absorption and significantly improved dimensional stability of the samples. Oven pre-drying followed by heat treatment at $180^{\circ}C$ for 6 hours resulted in good physical improvement of jabon and sengon wood. Fan pre-drying followed by heat treatment at $180^{\circ}C$ for 2 hours improved the physical properties of mangium wood. The heat treatment shows a promising technique for improving the physical characteristic of fast growing hardwoods.

• Journal of the Korean Wood Science and Technology
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• 제48권1호
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• pp.50-60
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• 2020

Fungi are wood-decaying organisms, and this is an important trait that should be considered in wood utilization. When fungi attack wood, it decreases the quality of the wood. The use of metal screws has become an important part of woodworking. The ability of fungi to decay wood and damage metal screws that are embedded into wood is varied. In this study, eight fungal species were evaluated with respect to their ability to decay Parashorea smythiesii and P. tomentella wood. In addition, the effect of fungi on corroding metal screws was determined using the Kolle flask method. The evaluation showed that the fungal species Schizophyllum commune, Pycnoporus sanguineus, and Polyporus arcularius were highly capable of decaying Parashorea spp. woods. The greatest wood weight loss occurred with the heartwood of P. tomentella exposed to S. commune. Based on the classification of wood resistance against fungal attack, the two Parashorea spp. were classified as moderately resistant woods (class III). Schizophyllum commune was classified as highly capable of decaying wood that was embedded with metal screws and was highly capable of corroding metal screws placed in fungi-culture media. The greatest weight of rust powder formed because of screw corrosion was obtained from screw-embedded wood exposed to S. commune. Additionally, the most severe corrosion of metal screws that were embedded into woods was caused by the activities of P. arcularius. Moreover, the average weight loss of screw-embedded wood was greater than that of unscrewed wood.

• Journal of the Korean Wood Science and Technology
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• 제41권3호
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• pp.187-200
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• 2013

본 연구에서는 목재보존제의 최근 국제적 동향 중, 비 구리계 약제를 중심으로 조사되었다. 최근의 목재보존제 연구 분야에서 다루어지는 비 구리계 약제로는 환경친화적 수용성약제 성분의 대표적인 붕소계 화합물이 가장 많았고, 자연에서 얻어지는 천연물질을 이용한 약제, 화학처리목재, pyrethroid계 방충제 등이 포함되었다. 인축 및 환경에 대한 사용안전성이 고려된 약제들이 주 연구대상이 되는 경향이 있었다. 붕소의 경우에는 옥외 사용 시 물에 대한 용탈성을 개선하기 위하여 다양한 고분자 등의 물질을 도입하여 정착성을 높이고자 하는 연구들이 주요 이슈였다. 또한 의학 분야에서 많이 다루어지던 천연물질이 목재보존제로써 사용하고자 하는 시도와 치수안정성을 목적으로 개발되었던 아세틸화 목재와 같은 화학수식목재에 대한 옥외 사용 시도가 눈에 띄게 증가된 경향을 나타내었다.

• Journal of the Korean Wood Science and Technology
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• 제49권6호
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• pp.643-657
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• 2021

목재문화 활성화 전략을 수립하기 위한 기초연구로써 일반인의 목재문화에 대한 인식정도와 유형별 목재문화자원의 체험현황에 대한 설문조사를 진행하였다. 응답자의 31.4%가 목재문화자원에 대하여 궁궐, 사찰, 한옥, 문화재 등 문화유산의 이미지를 갖고 있는 것으로 조사되었다. 목재문화자원에 대한 이미지가 없다는 응답자 중에서 목재문화자원의 개념이 모호하기 때문이라는 응답이 40.2%이었으며, 목재문화자원 자체를 생각해본 적이 없다는 응답이 40.1%이었다. 7가지로 분류된 목재문화자원의 중요도는 문화유산, 목조건축, 문화시설, 문화행사, 목재제품, 문화교육, 문화콘텐츠의 순서로 나타났다. 목재문화자원을 체험하기 위한 정보의 필요성과 충분성에 대한 설문에서 응답자의 46.7%는 다양한 정보가 필요하다고 하였으며, 응답자의 64.8%는 충분한 정보가 제공되지 않는다고 하였다. 향후 1년 이내에 목재문화를 체험하고 싶은 의향은 대부분의 목재문화자원에서 과반 이상의 응답율을 나타냈으나, 실제로 7가지 목재문화자원에 참여하였던 빈도는 일상생활에서 사용되는 목재제품을 제외하면 20% 내외로 나타났다. 이러한 결과를 토대로 일반인이 목재문화자원을 체험할 수 있는 기회를 확대하고 보다 대중화하기 위해서 다양한 콘텐츠를 개발하고, 일반인에게 홍보할 수 있는 체계적인 전략수립이 요구된다.

• Journal of the Korean Wood Science and Technology
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• 제45권6호
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• pp.828-835
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• 2017

Airtightness of buildings is one of critical aspects of its energy performance. To build up references of airtightness of wooden houses built in Korea, blower door tests have been carried out in 42 houses since 2006. Causes of air leakage were investigated recently. The average value of air change rate was $3.7h^{-1}$ for light frame house and $5.5h^{-1}$ for post-beam construction at ACH50 (air change per hour at 50 Pa air pressure difference). Foam type insulation was more advantageous in ensuring building airtightness than glass fiber batt. Airtightness of wooden houses which were constructed after 2010 was improved to have less than $1.5h^{-1}$ of ACH50, threshold for application of artificial air change. The average air change rate of CLT (cross laminated timber) houses showed the lowest value, $1.1h^{-1}$, among the tested structures.

• Journal of the Korean Wood Science and Technology
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• 제47권5호
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• pp.617-632
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• 2019

This study aimed to investigate the anatomical structure and fiber quality of four lesser-used wood species namely Benuang (O. sumatrana), Duabanga (D. moluccana), Pisang Merah (H. hellwigii), and Terap (A. odoratissimus). This study evaluated its suitability for raw material in pulp and paper manufacturing. The anatomical structure was observed macro- and microscopically. Macroscopic structures were observed directly to the wood samples, while microscopic characteristics were observed through microtome specimens. Fiber dimension was measured through macerated specimens and fiber quality was analyzed following the Rachman and Siagian's method. Results showed that these four timber species have similarity in the indistinct growth ring, diffuse porous in a radial pattern, rounded solitary vessel outline, 1 to 3 cells of ray width, deposits within the rays, fiber length, and cell wall thickness. Differences were found on vessel diameter, vessel grouping, vessel frequency, tyloses existence, type of axial parenchyma, and ray height. Based on fiber length and its derived values, the wood fibers of all species studied are suitable for pulp and paper manufacturing. They belong to the II quality class. The produced pulp and paper would have good quality, especially in tensile, folding, and tear strength. To promote their utilization, silviculture aspect of these four species has to be well understood.

• Journal of the Korean Wood Science and Technology
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• 제51권2호
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• pp.133-144
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• 2023

Densification is an effective method for improving the physical and mechanical properties of low-density wood. However, the set-recovery of dimensions was found to be the problem of densified wood due to low fixation during the densification process. Alkali pretreatment before densification is thought to be a modification process to improve the dimensional stability of densified wood. In this research, the wood samples used were boiled in a 1.25 N sodium hydroxide (NaOH) solution at different times, followed by densification for 5 h at 100℃. The alkali pretreatment for 1, 3, and 5 h of boiling increased the dimensional stability of densified woods and anti-swelling efficiency values were 8.52%, 63.24%, and 48.94%, respectively. The boiling of wood in NaOH solution decreased the holocellulose content, as well as lignin to a lesser degree, and a lower crystallinity index was observed. The lower hydroxyl groups and a higher proportion of lignin in treated samples seem to have contributed to the high dimensional stability detected.

• Journal of the Korean Wood Science and Technology
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• 제41권6호
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• pp.559-565
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• 2013

목재사용량의 증가에 따라 목재의 화재안전성에 대한 요구가 높아지고 있다. 실내 사용 목재의 난연처리에 무기인계를 약제로 사용함으로써 환경에 대한 부담을 줄이면서 난연성능을 향상 시킬 수 있다. 수용성 약제를 가압 주입하여 목재 내 깊숙이 침투시키면 목재의 고유기능을 유지하면서 난연성능을 부여 할 수 있다. 난연제의 용탈을 억제하여 장기간 성능을 유지할 수 있는 장점도 있다. 저자들은 액상규산나트륨을 주약제로 하고, 붕산 및 인계 약제를 보조약제로 하여 목재 내로 약액을 주입하는 공정을 개발하였다. 이들 약제는 난연성능 외에 방부 및 방충성능을 지니는 약제가 포함되어 있어, 난연성능과 함께 목재 사용 시 노출될 수 있는 부후환경에서의 내후성능을 방미효력과 방부효력으로 평가하였다.