• Journal of the Korean Wood Science and Technology
• /
• 제32권6호
• /
• pp.23-35
• /
• 2004

The goal of study was to investigate the influence of the acrylated urethane oligomer on mechanical properties, the chemical resistance and thermal resistance of the UV curable urethane acrylate coatings for fancy veneer overlayed plywood flooring. The pencil hardness and abrasion resistance of the coated fancy veneer overlayed plywood floorings increased with increasing the acrylate functionality of the acrylated urethane oligomer. In the case of the UV cured film containing hexa-functional acrylated aliphatic urethane oligomer, high discoloration of the coated fancy veneer overlayed plywood flooring was observed near the cracks at the beginning of the chemical treatment. In this study, it was found that the degradation of the UV cured film caused by an alkaline reagent was higher than that of the UV cured film caused by an acidic treatment.

• Journal of the Korean Wood Science and Technology
• /
• 제36권2호
• /
• pp.46-55
• /
• 2008

This study assesses the formaldehyde and TVOC emissions from bio-composites with attached fancy veneer manufactured using wood flour and polypropylene (PP) measured using the Field and Laboratory Emission Cell (FLEC) method and 20 L small chamber method. To determine and compare the effects of the adhesive, samples were prepared with different manufacturing methods. In the FLEC result, the formaldehyde emission level of the bio-composites with attached veneer by hot-press was the lowest than pure bio-composite and bio-composite attached veneer using adhesive. The TVOC emission levels are similar to the formaldehyde emission. The TVOC emission level is very low in all of the samples except fancy veneer that is attached with bio-composites using adhesive. The TVOC emission varies depending on how attaching fancy veneer. The results of the 20 L small chamber method were very similar to those obtained with the FLEC, but the correlation was not perfect. However, the FLEC method requires a shorter time than the 20 L small chamber method to measure the formaldehyde and TVOC emissions. The internal bonding strength exceeded the minimum value of $0.4N/mm^2$ specified by the KS standard. All of the bio-composites with attached veneer satisfied the KS standard.

• Journal of the Korean Wood Science and Technology
• /
• 제38권5호
• /
• pp.385-390
• /
• 2010

This study was carried out to manufacture very thin natural elm veneer overlaid charcoal board for enhancing aesthetic value of charcoal board for the indoor application, and to use the advantageous properties of the charcoal as a building material for solving the sick house problem. The thin elm veneer had 26.9% opening ratio. The experiment results showed that the spreading area and the nonvolatile content of adhesive did not affect the gas adsoprtion of fancy veneer overlaid charcoal board. The natural thin elm veneer overlaid charcoal board enhanced not only the aesthetic beauty but also showed the same gas adsorption by the charcoal board.

• Journal of the Korean Wood Science and Technology
• /
• 제39권5호
• /
• pp.451-458
• /
• 2011

Adhesives derived from renewable resources allow wood panel producers to make lower cost alternatives to formaldehyde-based adhesive resins. Among them, adhesive components extracted from industrial by-products or wastes are the most important research fields in the efficient utilization of waste and cost reduction. In our study, the rapeseed flour, which is a by product from the production of biodiesel extracted from rapeseed, was introduced to develop alternative adhesives for the production of wood flooring. The rapeseed flour was hydrolyzed with 1% sodium hydroxide solution and PF prepolymers were prepared with 3-molar ratios, 1.8, 2.1 and 2.4. The linear fracture mechanics was introduced to evaluate the glue bond quality in wood flooring composed of fancy-veneered and plywood, and the formaldehyde emission and adhesive penetration were also investigated. The formaldehyde emissions of wood flooring met the requirement of the standard of $SE_0$ specified in the KS standard. The rapeseed flour adhesive penetrated sufficiently into the vessel elements and lumens in fancy veneer and plywood and gave strong bond quality to the wood flooring. The fracture mechanics was introduced to evaluate the adhesive joint between fancy veneer and plywood. The critical stress intensity factor ($K_{IC}$) of boliva overlayed wood flooring was increased with increasing molar ratio and this was the same tendency in oak overlayed wood flooring. From the results, the formulated adhesives were efficiently used to bond fancy veneer onto the plywood to make wood flooring and showed a potential to be used as a component of environmentally friendly adhesive resin systems for production of flooring.

• 한국가구학회지
• /
• 제18권1호
• /
• pp.13-19
• /
• 2007

The influences of coating on oak veneer overlaid Medium Density Fiberboard (MDF) were evaluated. The hardness of 9mm-MDF by hardness test were increased about 28% with coating on MDF and the more increased hardness of 31% with oak veneer overlaid MDF. The hardness of veneer overlaid MDF increased with increment of the veneer thickness and that of overlaid MDF showed the higher hardness compared to non-overlaid MDF. The optimum moisture content in terms of the hardness of panels MDF was in the range of 7% to 10% and the hardness was decreased with increasing of the moisture content. Any cracks were not overlaid coated on the MDF but the cracks were observed on the overlaid MDF after Soak under Vacuum Dry 10-cycle. The thicker veneer-overlaid MDF showed more cracks.

• Journal of the Korean Wood Science and Technology
• /
• 제33권4호통권132호
• /
• pp.23-29
• /
• 2005

대표적인 고부가가치 목질판상 재료인 마루판은 육안 분류 작업에 의한 오차로 마루판 시공 시에 무늬목간의 색상 차가 생기고 있다. 이는 조건등색(metamerism)에 의해 식별 후 혹은 마루판 시공 시에 오차가 큰 것으로 나타났다. 따라서 본 연구에서는 Light와 Dark 두 단계로 육안 식별한 피나무, 자작나무, 단풍나무 3수종의 무늬목을 사용한 마루판을 CIELAB를 이용하여 분류하고, CIERGＢ에서 각각의 문턱 값(threshold)을 조사하고, 인간의 색 인지에 기반을 둔 HSI (hue, saturation, intensity)색상모델을 응용하여 색상, 채도, 명도 값의 범위를 조사하였다. HSI색상모델의 색상과 채도, 명도를 이용하여 마루판의 색상분류에 사용할 경우 명도 값을 이용하는 것이 유리할 것으로 보인다. 그리고 색상의 범위가 3종류 모두 $45{\sim}55^{\circ}$ 사이 범위 값을 가지고 있는 것으로 보이며, RGB성분의 문턱값을 이용한 분류의 경우 특정 색상 성분 값만으로는 마루판 무늬목의 분류가 어려울 것으로 보인다.

• 한국가구학회지
• /
• 제21권4호
• /
• pp.284-292
• /
• 2010

This research was carried out to examine the properties of fancy cherry veneer overlaid on the PF resin bonded Meranti plywood floor, which 2.5% green tea leaf powder was applied in the UV varnishes and the adhesives for scavenging the volatile organic compounds. The results were as follows: 1. The various properties of the treated samples, such as density, moisture content, thickness swelling, bending strength(MOR), adhesion shear strength, surface abrasion, curling, cyclic delamination test with boiling water, boiling property, cold-resistance and heat resistance, acid resistance and alkali resistance, and anti-contamination property showed no significant difference between the properties of the control samples. 2.5% green tea leaf powder treated floor gave a little better results than the control for surface scratch test. 2. In case of QUV and weathering test, no difference between the treated sample and control was found. 3. The floor was discolored by adding 10% green tea leaf powder to UV coating, and the floor was also discolored to light green during by the soaking test. The color of floor was not changed up to 5% addition level.

• Journal of the Korean Wood Science and Technology
• /
• 제35권5호
• /
• pp.58-66
• /
• 2007

The objective of this research was to develop environment-friendly adhesives for face fancy veneer bonding of engineered flooring. Urea-formaldehyde (UF)-tannin and melamine-formaldehyde (MF)/PVAc hybrid resin were used to replace UF resin in the formaldehyde-based resin system in order to reduce formaldehyde and volatile organic compound (VOC) emissions from the adhesives used between plywoods and fancy veneers. Wattle tannin powder (5 wt%) was added to UF resin and PVAc (30 wt%) to MF resin. These adhesive systems showed better bonding than commercial UF resin with a similar level of wood penetration. The initial adhesion strength was sufficient to be maintained within the optimum initial tack range. The standard formaldehyde emission test (desiccator method) and VOC analyzer were used to determine the formaldehyde and VOC emissions from engineered flooring bonded with commercial UF resin, UF-tannin and MF/PVAc hybrid resin. By desiccator method, the formaldehyde emission level of UF resin showed the highest but was reduced by replacing with UF-tannin and MF/PVAc hybrid resin. MF/PVAc hybrid satisfied the $E_1$ grade (below $1.5mg/{\ell}$). VOC emission results by VOC analyzer were similar with the formaldehyde emission results. TVOC emission was in the following order: UF > UF-tannin > MF/PVAc hybrid resin.

• Journal of the Korean Wood Science and Technology
• /
• 제37권4호
• /
• pp.388-396
• /
• 2009

본 연구에서는 두부비지 가수분해물과 페놀수지로 조제된 마루판 화장용 접착제의 접착성능을 확인하기 위하여 수행하였다. 먼저 두부비지를 황산과 수산화나트륨으로 화학적으로 개량한 후 가교제로 phenol formaldehyde (PF) prepolymer와 혼합하여 접착제를 조제하였는데, 이 접착제는 고형분 함량을 기준으로 35%의 황산 가수분해물(AC), 35%의 수산화나트륨 가수분해물(AK) 그리고 30%의 PF로 조제하였다. 이렇게 조제된 접착제를 고밀도섬유판에 $300g/m^2$의 비율로 도포한 후 참나무 무늬목을 접착시켜 $7kg/m^2$의 압력으로 $120^{\circ}C$에서 열압하여 마루판을 제조하였다. 제조된 마루판에 대하여 formaldehyde/phenol 몰비(1.8, 2.1, 2.4), 퇴적시간(0분, 10분, 20분), 열압시간(90초, 120초)이 평면인장강도, 준내수 박리율, 포름알데히드 방산량에 미치는 영향에 대해 조사하였다. 두부비지 접착제를 이용하여 제조된 목질마루판의 평면인장강도는 KS 규격의 최소값을 상회하였으며, 대부분의 포름알데히드 방산량 값은 KS 규격의 E0 기준에 근접하는 것으로 나타났다. 따라서 두부비지 접착제가 마루판 화장용 접착제로 사용될 수 있다는 가능성을 보여 주었으나, 상용화를 위하여 내수성의 향상과 포름알데히드 방산량의 저감을 위한 연구가 필요할 것으로 생각한다.

• Journal of the Korean Wood Science and Technology
• /
• 제36권6호
• /
• pp.49-58
• /
• 2008

본 연구는 내구성이 우수하며 포름알데히드방출이 적은 페놀수지 사용 메란티합판을 마루판용 대판으로 사용하고 북미산 벚나무 단판을 표면재료로 사용한 마루판의 제조과정에서 접착제 및 도료에 녹차잎 분말을 첨가하였을 때 마루판으로부터 방출하는 총휘발성유기화합물(TVOC)과 포름알데히드의 감소효과와 녹차잎 분말의 적정 첨가량을 구명하였다. 1) 녹차잎 분말의 폴리페놀화합물량은 9.85%였다. 2) 녹차잎 분말은 FT-IR 결과 벤즈알데히드와 에틸헥사알콜과 반응하여 화학결합을 하는 것으로 나타났다. 3) 페놀수지메란티대판에 벚나무단판오버레이 마루판 제조를 위한 접착제와 UV도료에 전건중량기준으로 2.5%의 녹차잎 분말을 각각 첨가하는 것이 총휘발성유기화합물과 포름알데히드의 방산제거 효과가 매우 적절한 것으로 나타났다. 4) 20L 소형챔버법에 의한 녹차잎 분말 2.5%를 접착제와 도료에 각각 첨가한 온돌용 마루판의 7일째 TVOC는 $0.089mg/m^2hr$이고 포름알데히드는 $0.001mg/m^2hr$를 나타내 최우수등급으로 나타났다.