• Journal of the Korean Wood Science and Technology
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• v.48 no.1
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• pp.107-116
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• 2020

Termiticidal and fungicidal activities of wood vinegar from Cinnamomum parthenoxylon (CP) stem wood have been evaluated against Coptotermes curvignathus and wood rotting fungi (Schizophyllum commune and Fomitopsis palustris). The utilized CP wood vinegar was produced in the operating temperature range 250-300℃ pyrolysis. A no-choice test was applied for evaluating termiticidal activity with 33 active termites and antifungal activity using the agar media assay. The result showed that an increase in the concentrations of CP wood vinegar significantly raised the mortality of termite. CP wood vinegar showed high termiticidal activity, organic acids (acetic acid 42.91%, 3-butenoic acid 6.89%, butanoic acid, 2-propenyl ester 2.26%), and ketones (1-hydroxy-2-propanone 5.14%, 3-methylcyclopentane-1,2-dione 2.34%) might be largely contributed to termiticidal activity in addition to other minor components. Furthermore, CP wood vinegar exhibited significant inhibition of fungal growth. These data showed that CP wood vinegar was more toxic to white-rot fungi (S. commune) than brown-rot (F. palustris). The results suggested that phenolic compounds from lignin degradation were responsible for good antifungal activity.

• Journal of Korea Foresty Energy
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• v.21 no.2
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• pp.34-42
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• 2002

This research was carried out to investigate water repellent effectiveness of natural oil treated wood. Linseed oil, castor oil, olive oil, bean oil, perilla oil and sunflower oil were used in this test. For evaluation of water repellent of natural oil treated wood, moisture absorption test, water-drop contact angle test and color difference test of accelerated decomposition by UV and water were used. The moisture absorption amount of natural oil treated wood was less than untreated wood until 3 hours, but it was increased with time, there was no big difference with oil treated wood and untreated wood after 48hours. Oil treated wood and untreated wood showed big difference on contact angle test. It was no big difference by kind and oil concentration. Natural oil treated wood did not showed stability on the weather aging test. Contact angle test could be used on evaluation of wood surface status treated with natural oil.

• Journal of the Korean Institute of Rural Architecture
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• v.21 no.1
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• pp.37-44
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• 2019

Recently, various tourist products using hanok have increased rapidly. In the meantime, there is a steady demand for Hanok architecture. However, there are many negative perceptions about wood deformation and biodeterioration. Wood deformation and biodeterioration are related to moisture content. And the cracks occur in the process of removing water from the wood. Therefore, this study investigates the moisture content and cracks of dried hanok made of wood according to the drying method of wood. Drying methods include natural seasoning and artificial seasoning. There was a difference in moisture removal depending on drying period and method of natural seasoning. Drying time should be about 3 years for natural seasoning, so the moisture content of the wood is stable. In addition, the moisture absorption rate was low even in a humid environment where the voids were removed. However, natural seasoning is time consuming. Artificial seasoning, on the other hand, can quickly remove moisture from the wood and reduce porosity, but it is costly. Cracks that occur during the drying of wood may become problematic in appearance and stability due to wider spacing over time. As a result, the difference in the moisture content of the timber depending on the drying method and drying period of the wood was maintained even after the formation. These gaps appeared to be differences in moisture absorption in a wet environment.

• Journal of the Korean Wood Science and Technology
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• v.33 no.2 s.130
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• pp.17-23
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• 2005

Juvenile and transitional-juvenile wood samples from loblolly pine (Pinus taeda) were immersed in water to investigate longitudinal and tangential swelling properties. Increment cores from twenty-six loblolly pine trees were sampled at breast height (1.37 m). Earlywood rings 5 and 9 were separated from the core, extracted, oven-dried and immersed in water at room temperature. The variance in longitudinal swell was significant for ring 5 compared to ring 9 (p = 0.001). It was found that tangential swell might predict longitudinal swelling of juvenile wood at ring 9 but not at ring 5. Poor correlation in ring 5 suggests that swelling response in younger juvenile wood may differ. The swell response at ring 5 did not follow the shrinkage models discussed in the literature while ring 9 adhered to the expected curve.

• Textile Coloration and Finishing
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• v.19 no.6
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• pp.12-20
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• 2007

Four kinds of natural dying solutions (natural colorant extracts)were obtained by extraction from sappan wood, black tea, peony, and clove using water as extracting solvent at $90^{\circ}C$ for 90 min with liquor ratio (solid natural colorant material/solvent water, weight ratio) of 1/10. The dyeing, colour fastness and deodorizing properties of fabrics (cotton, silk, and wool fabrics) dyed with natural colorant extracts were compared. It was found that these properties were significantly dependent on the concentration of extracts, the structure of colorant, and the kind of fabrics. The K/S value of dyed cotton fabric increased in the order of peony < sappan wood < clove < black tea, however, the values of dyed silk and wool fabrics were in the order of peony < sappan wood < black tea < clove. Colour fastness (light, water, and perspiration fastness) was in the range of 3 - 5 grade except for sappan wood. The deodorizing performance of fabrics dyed with various natural colorants extracts was in the range of 56 - 99%. The deodorizing performance increased in the order of peony < black tea < sappan wood < clove. Especially, the deodorizing performance of all fabrics dyed with clove was found to be the highest at 98-99%.

• Journal of the Korean Wood Science and Technology
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• v.48 no.2
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• pp.154-165
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• 2020

To assign the functionality of the regenerated fiber from waste MDF(wMDF) made of pitch pine, we examined the dyeing characteristics of natural dyes, sappan wood as a polychromatic natural red series, monochromatic gardenia as a yellow series, and indigo blue series. For nonemordanting dye, the colors of regenerated fiber dyed by sappan wood and gardenia were reddish yellow (YR) and yellow (Y) series, respectively, and dyeing conditions were appropriate a 30 ~ 50 g/L of dyeing materials at 60 ℃ for 60minutes of dyeing time. We obtained regenerated woody dyed fibers (Re-WDF), YR to the red (R) series by premordanting with Al and Cu mordant for sappan wood and the purplish red (RP) series by Fe premordanting. In the case of gardenia, only Y series colors were developed in nonemordanting dye or all three mordants. Indigo dye produced Re-WDF with greenish yellow (GY) tone at 1%, green (G) tone at 3%, and blue (B) tone at 5% concentration or more. Re-WDF with indigo showed the best light fastness followed by sappan wood and gardenia. In particular, the light fastness of Re-WDF with gardenia was very poor. The light fastness was somewhat improved by premordanting(Fe>Cu>Al) both sappan wood and gardenia dyes.

• Journal of the Korean Wood Science and Technology
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• v.49 no.5
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• pp.471-481
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• 2021

This study investigated the hygroscopicity and UV deterioration characteristics of 3 domestic and 4 imported woods using natural oil, stain, and varnish paints. In terms of hygroscopicity, it was found that the hygroscopicity of the painted wood was lower than that of the unpainted wood, and that as the number of coatings increased, the hygroscopicity decreased. In terms of anti-absorption, oil-based chemical paints showed higher resistance than water-based paints, and natural oils showed results comparable to oil-based paints. As for the UV deterioration, the amount of color change of the painted wood was lower than that of the unpainted wood, and there was no significant difference according to the number of times of painting. The amount of color change was found to be low in oil-based paints and hardwoods. Through this study, we confirmed effective moisture blocking and small color changes during painting using paints, and it is believed that wood can be protected from internal and external defects through selective and efficient painting based on data for excellent painting performance.

• Journal of the Korea Furniture Society
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• v.26 no.1
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• pp.22-30
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• 2015

In order to prevent decay, distortion, bending, twist on wood products such as wooden furnitures, variety of coating materials were developed and used so far. The coating materials for wood finishing can be synthesized by natural resource or petroleum. However, these coating materials can cause contamination of indoor air quality due to emission of volatile organic compounds (VOCs). In this study, commercialized coating materials for wood finishing such as varnish, coat, and stain were evaluated on emission characteristics of VOCs. Among the varnish, eco-friendly products had about 15~46% lower TVOC emission ($1,042{\mu}g/m^2h{\sim}3,257{\mu}g/m^2h$, respectively, than typical product ($7,100{\mu}g/m^2h$). Natural resource based coating material showed lowest TVOC emission level. However, one of natural resource based waterborne stain showed higher TVOC emission level because waterborne stain already contained higher amount of natural VOC. Oil-based stain might not be suitable for indoor use on interior wall and furniture due to exceed amount of TVOC. Based on results, natural resource based coat or waterborne stain are recommenced to use on wood products.

• Journal of the Korea Furniture Society
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• v.25 no.3
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• pp.223-232
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• 2014

To make metalized wood composites of 10 different korean wood species, it was tested by Low temperature melting Bi-Sn alloy injection method at high temperature and high pressure condition. Metalized wood composite of each wood species had light ash color, but still maintained its own natural wood grain and wood figures. It was evaluated on coating properties. Furthermore, it also was check on effect of coating as like a changes of main color, wood grain and wood figures. The results of test were following as; a coating properties as like a cold resistance, heat resistance, acid resistance, alkali resistance, durability of abrasion, and cross-cut test was proper on the conditions of the KS standard. And, In aspect of color changes, the metalized wood composites of 10 different korean wood species had a light ash color, but still maintained its own natural wood grain and wood figures. Also, the more weight per gain of alloy is, the more grey background of metalized wood composite is.

• Journal of the Korean Wood Science and Technology
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• v.38 no.4
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• pp.341-348
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• 2010

Antifungal and antibacterial activities of wood vinegars were investigated in this study in order to apply for the natural fungicides and food preservatives. The antifungal activities of wood vinegars were measured as a hyphal growth inhibition rate using four plant pathogenic, four wood rot and one mushroom pathogenic fungi. Inhibition effect on the fungi growth was explicitly observed at the concentrations higher than 0.5% of unrefined wood vinegar and higher than 1.0% of refined wood vinegar, respectively, suggesting that unrefined wood vinegars showed the higher antifungal activities than that of refined wood vinegars. The highest inhibition effect on the fungi growth was shown in Libertella betulina which is a mushroom pathogenic fungus. In addition, the wood vinegars from Pinus densiflora showed the higher antifungal activities against the plant pathogenic and wood rot fungi than that from Quercus spp.. On the other hand, the antibacterial activities of wood vinegars were determined by a paper disc method using the three gram positive and five gram negative bacteria. The unrefined wood vinegars showed a prominent effect on the suppression of bacteria growth at the concentration of 10%, while the suppression of bacteria growth was not observed in the refined wood vinegars. These results also suggest that the unrefined wood vinegars showed the higher antibacterial activities than the refined wood vinegars. The antibacterial activities of wood vinegars against gram positive bacteria were higher than those of wood vinegars against gram negative bacteria. From these results, it can be inferred that the wood vinegars has the strong antimicrobial activities and can be applied as the natural fungicides and food preservatives.