• 한국가구학회지
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• 제12권2호
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• pp.1-10
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• 2001

As finger joint method has a high rate of yield and high strength and ease in working, it has been widely used as an end joint method for solid wood and wood based-material. Therefore, we end-joined the material of Pinus densiflora, Quercus variabilis and populus euramericana with polyvinyl acetate adhesive and resorcinol phenol resin adhesive. The effect of difference (0, 0.15, 0.3, 0.45mm) between the dimensions of tip width and root width of the finger (DTRW) on bending strength properties was as follows: 1. In the case of polyvinyl acetate adhesive, DTRW had no effect on bending modulus of elasticity(MOE) and modulus of rupture(MOR) of the three kinds of species, because their bonding layers were destroyed by slippage, not their woody parts. 2. In the case of resorcinol phenol resin adhesive, the material of Quercus variabilis showed an optimal result at 0.15 or 0.3 of DTRW, while the poplar did at 0 of DTRW 3. The differences in efficiency ratio of bending MOR of populus euramericana, Pinus densiflora and Quercus variabilis species according to the kind of adhesive were 13-29%, 23-30% and 45-53%, respectively.

• 한국가구학회지
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• 제25권3호
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• pp.207-212
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• 2014

With increased interests in environmental issues, people are looking for new materials that serve special and bio-activated functions. One of interesting materials is charcoal which has excellent adsorption ability for harmful volatile organic compounds, fireproof performance, far-infrared ray emission, and electromagnetic shielding. Since non-crack carbonized board was developed from wood-based composite materials, carbonization method might be applied to woodcraft products such as wood cup and bamboo. In this study, manufacture of wood charcoal bowl was conducted with carbonization method developed in 2009 in order to activate wood products market. Ash tree(Fraxinus rhynchophylla) cup was carbonized at $600^{\circ}C$ with two pretreatments which were phenol resin and wood tar solution treatment. After carbonization of ash tree cup, non-crack charcoal cup were successfully manufactured. Phenol resin treatment affected on charcoal cup manufacturing both positively and negatively. For a positive way, it prevented shrinkage. For a negative way, it decreased water repellency. On the contrary, wood tar treatment accelerated shrinkage a bit and increased water repellency. Based on the results, wood tar can be used as pre-treatment solution for reducing post-treatment costs. We confirmed woodcraft products can be carbonized without deformation, so carbonization may provide a high value-added products from wood.

• Journal of the Korean Wood Science and Technology
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• 제24권1호
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• pp.95-99
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• 1996

The bending and compression strength properties of two types Rhus verniciflua specimens, which made of no heat-treated wood and heat-treated wood for urushiol extraction, were measured. The heat-treated specimens were finger-jointed with either resorcinol-phenol or polyurethane resin adhesives, and the vertical type bending strength property was also measured in these specimens. The results obtained are as follows ; 1. The correlation coefficient between the compression strength and specific gravity in the specimens of no heat-treated and heat-treated wood was high. However there was no difference in compression strength property as affected by heat treatment. 2 The correlation coefficient between the bending strength and specific gravity in the specimens of no heat-treated and heat-treated wood was also high. However, there was no difference in bending strength property as affected by heat treatment. 3 The bending test showed high correlation between modulus of elasticity and modulus of rupture for the specimens made of no heat-treated and heat-treated wood. However, there was no difference in bending strength property between the specimens made of heat-treated and no heat-treated wood. 4. The efficiencies of bending strength test on the finger-jointed specimens of heat-treated wood with resorcinol-phenol and polyurethane resin adhesives were 0.85, 0.81. respectively.

• 한국세라믹학회지
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• 제51권6호
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• pp.539-543
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• 2014

Foam type porous silicon carbide ceramics were fabricated by a polymer replica method using polyurethane foam, carbon black, phenol resin, and silicon powder as raw materials. The influence of the C/Si mole ratio of the ceramic slurry and heat treatment temperature on the porous silicon carbide microstructure was investigated. To characterize the microstructure of porous silicon carbide ceramics, BET, bulk density, X-ray Powder Diffraction (XRD), and Scanning Electron Microscope (SEM) analyses were employed. The results revealed that the surface area of the porous silicon carbide ceramics decreases with increased heat treatment temperature and carbon content at the $2^{nd}$ heat treatment stage. The addition of carbon to the ceramic slurry, which was composed of phenol resin and silicon powder, enhanced the direct carbonization reaction of silicon. This is ascribed to a consequent decrease of the wetting angles of carbon to silicon with increasing heat treatment temperature.

• 한국포장학회지
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• 제11권1호
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• pp.33-40
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• 2005

This study was carried out for effective utilization of recycling resources to investigate the repulping conditions of car air filter waste paper and to evaluate the application into corrugating medium papermaking by blending these repulped pulps. Car air filter waste paper was made of virgin BKP and it was dipped into phenol resin solution. It was well disintegrated by laboratory Valley beater with 10%(basis on oven-dried pulp weight) NaOH addition and defoamer usage. The optimal temperature, beating consistency and treatment time were mainly $40^{\circ}C$, 1% and $30{\sim}40$ minutes, respectively. Handsheets were prepared with various blending ratios between air filter recycled pulp and KOCC. In the case of $10{\sim}20%$ substitution with air filter recycled pulp, physical properties reductions as compressive strength and burst strength of sheets were lower than others. These results showed more favour than the partial substitution of KOCC for corrugating medium even though some strength reduction of paper. It was also observed that the waste water of air filter recycling was not affective to environmental problems.

• Journal of the Korean Wood Science and Technology
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• 제27권1호
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• pp.30-36
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• 1999

소나무를 재료로 경사핑거접합법으로 레소시놀계수지, 유용성 우레탄수지, 초산비닐수지, 초산비닐과 아크릴을 혼합한 수지접착제롤 사용하여 제작한 시험재의 휨강도 성능과 휨 시험시 발생하는 AE 특성에 대한 연구결과는 다음과 같다. 초산 비닐, 유용성 우레탄 수지접착제를 사용한 소나무경사 핑거접합재의 하중과 AE 사상총수는 휨 강도가 낮을수록 빠른 시기부터 AE가 발생하고 AE의 증가속도가 빨라 하중-AE 사상총수의 관계곡선의 기울기가 급격하게 나타났다. 레소시놀 수지 접착제로 제작한 시편은 아주 낮은 하중에서부터 하중이 증가함에 따라 연속적으로 AE가 발생하였고 발생수도 많았다. 경사 핑거접착제의 휨 하중과 AE 특성간에는 서로 잘 대응되어 휨강도 측정이나 보정은 휨 탄성계수로서는 예측이 어렵지만 하중과 AE, 사상총수의 초기 치로부터 얻어지는 AE지표 치로서 휨 강도의 예측이나 보증이 가능 할 것으로 판단된다.

• 조명전기설비학회논문지
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• 제23권2호
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• pp.161-167
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• 2009

저전압용 절연체로 사용되는 유기절연재료는 누설전류에 의하여 탄화되는 경우 고유한 탄화특성을 나타낸다. 그러므로 유기절연재료의 탄화특성을 이용함으로써 유기절연재료의 표면을 흐르는 누설전류로 인한 전기화재를 규명하는 것이 가능하다. 이와 같은 탄화특성을 이해하기 위하여 본 논문에서는 대표적인 유기절연체로 알려진 페놀수지, PVC, 그리고 아크릴수지를 누설전류에 의하여 탄화시키는 실험을 수행하고 시료의 탄화패턴과 적외선 흡광 스펙트럼을 분석하였다. 탄화패턴 분석에 의하면 페놀수지는 열경화성 성질 때문에 소위 'spider-leg'의 탄화패턴이 형성된다. 페놀수지와 다르게 PVC와 아크릴 수지의 표면에서는 열가소성 성질 때문에 탄화원인을 규명할 수 있을 정도의 분명한 탄화패턴을 관찰하기 어렵다. 이 경우 적외선 흡광 스펙트럼의 분석을 통하여 누설전류로 인하여 탄화된 시료의 특성을 규명할 수 있다 분석결과, 누설전류에 의해 탄화된 PVC의 경우에 파수 $3,400[cm^{-1}]$, $1,618[cm^{-1}]$에서 흡광피크가 검출되었으며 이것은 탄화원인을 규명할 수 있는 중요한 인자가 될 수 있다.

• 대한화학회지
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• 제20권3호
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• pp.240-243
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• 1976

리그닌을 알칼리로 活性化시키고 페놀 및 포름알데히드와 反應시켜 새로운 樹脂를 合成하였다. 合成된 樹脂는 木材의 接着劑로 쓸 수 있는 충분한 强度를 가졌음을 확인하였다.

• Journal of the Korean Wood Science and Technology
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• 제39권1호
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• pp.21-27
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• 2011

This study was carried out to examine properties of water resistant plywood by using serum protein adhesive which is natural, environment-friendly and human-friendly. For the preparation of the serum protein adhesive, pig blood from slaughterhouse was centrifuged and serum was separated from corpuscles and concentrated to 30% by dry weight basis. This concentrated serum protein was modified with PF resin (50% NVC) with the ratio of 9 : 2.5. Plywood made by this modified serum protein gave 1.21 N/$mm^2$ of dry bonding strength, 0.80 N/$mm^2$ of wet boil bonding strength, 0% of cyclic delamination test value, and 0.025 ppm of HCHO emission, which met the excellent super $E_0$ grade and water resistant plywood.

• 한국인쇄학회지
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• 제24권1호
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• pp.1-12
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• 2006

The rheological characteristics of an ink relate to its performance on the press and to the printing quality such as ink stability, transfer characteristics, mottle, squash, misting, dot gain, and so on. For lithographic print, the emulsification of ink is an important factor to determine the product. And also the rheological characteristics of the emulsified ink should be investigated. Thus, in this study, the effects of the changing molecular weight of rosin modified phenolic resin on the water-pickup ratio of neat inks were studied. And then rheological properties of neat inks and emulsified inks with changing molecular weight of rosin modified phenolic resin were analyzed by using rotational rheometer.