• Journal of the Korean Wood Science and Technology
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• 제31권1호
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• pp.22-26
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• 2003

증량제로서 카제인과 콩을 첨가한 요소수지 접착제와 소나무 간벌재 파티클로 실험실 파티클보드를 제조하였다. 소나무 간벌재 파티클로 제조된 파티클보드를 성능 평가한 결과 소나무 간벌재는 파티클보드의 원료로서 적합하다. 증량된 요소수지로 접착된 파티클보드는 증량제의 첨가량이 증가함에 따라 기계적인 성능은 감소하는 경향이었다. 그러나 요소수지 접착제의 고형분량에 대해 카제인은 15%까지 콩은 20%까지 첨가하여 파티클보드 제조에 사용할 수 있다.

• Journal of the Korean Wood Science and Technology
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• 제22권1호
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• pp.44-53
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• 1994

This research was carried out to investigate the effect of paper sludge addition on formaldehyde emission, and physical and mechanical properties of UF-particleboard. In order to investigate the effect of paper sludge addition to resin, particleboards were bonded with urea-formaldehyde resins containing 5, 10, 15% paper sludge powders of three types(A Type: -200 mesh, B Type: -100~+200 mesh. C Type: -50~+100 mesh), based on weight of resin solid. Also the effect of paper sludge addition to furnish was studied from particleboards fabricated with ratios of sludge to particle of 5:95, 10:90, 15:85 based on oven-dry weight. Tests were conducted on the manufactured particleboards to determine formaldehyde emission, bending properties, internal bond strength and thickness swelling. The obtained results were summarized as follows: The addition of paper sludge powder to resin yielded a higher pH of cured resin. Formaldehyde emission decreased with the increase of paper sludge powder addition to resin and paper sludge composition ratio to furnish. Particleboard bonded with urea-formaldehyde resin containing paper sludge powder and particleboard mixed with paper sludge have similar bending properties(MOR, MOE) and thickness swelling compared with control particleboard. Internal bond strength of particleboards treated with paper sludge were lower than that of control particleboard. The use of paper sludge as scavenger was achieved reduction of formaldehyde emission without depression of physical and mechanical properties of particleboard. Also the use of paper sludge was able to concluded that there is possibility of partial substitution of wood particle materials.

• 한국토양비료학회지
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• 제24권1호
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• pp.50-54
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• 1991

조입성형제(造粒成型劑)로 사용(使用)된 요소수지(尿素樹脂)의 U/F반응(反應) mole비(比) 및 첨가량(添加量)이 각각(各各) 다른 시제품(試製品) 5종(種)을 단비분시(單肥分施)를 대조(對照)로 배추에 대(對)한 비효시험(肥效試驗)을 실시(實施)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 배추수량(收量)은 U/F반응(反應) mole비(比) 1.0인 요소수지(尿素樹脂)가 6.7% 첨가(添加)된 시제품(試製品) V에서 가장 높았고 U/F반응(反應) mole비(比)가 가장 낮고 첨가량(添加量)이 가장 많은 시제품(試製品) VII에서는 3요소(要素) 분시구(分施區)에 비(比)하여 감수(減收)하였다. 2. 배추용(用) 완효성(緩效性) 복비(複肥)의 질소(窒素) 완효도(緩效度)는 24시간후(時間後) 수중전질소(水中全窒素) 용출률(溶出率) 76.1%, 100일후(日後) 토양중(土壤中) 전질소(全窒素) 용출률(溶出率) 71.7%가 적합(適合)하였다.

• 대한환경공학회지
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• 제22권12호
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• pp.2135-2139
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• 2000

시아노구아니딘-포름알데히드 수지에 의한 음이온성 콜로이드 입자의 응집현상은 음이온성 입자의 표면전하와 디아미노메틸렌우레아(diaminomethylene urea: DU) 이온과의 전기적인 작용에 기인한다고 보고되어 있다. 본 논문에서는 음이온성 염료폐수를 응집처리하기 위하여 100~500 nm의 양이온성 시아노구아니딘-포름알데히드 수지를 합성하였고, 응집제 수용액의 pH가 낮을수록 응집제의 Zeta potential은 높게 측정되었다. 농도 0.4 g/L 반응성 염료폐수를 응집처리하였을 경우 pH가 3, 5, 7, 9, 11 중에서 pH가 3인 조건이 다른 pH조건보다 COD, 색도 제거율이 높게 나타났으며, pH 3인 조건에서 400 ppm 주입시 COD 74%, 색도 90% 정도 제거할 수 있었다.

• Journal of the Korean Wood Science and Technology
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• 제43권5호
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• pp.672-681
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• 2015

As a part of abating the formaldehyde emission of amino resin-bonded wood-based composite panels, this study was conducted to investigate hydrolytic stability of urea-melamine-formaldehyde (UMF) resin depending on various hydrolysis conditions and hardener types. Commercial UMF resin was cured and ground into a powdered form, and then hydrolyzed with hydrochloric acid. After the acid hydrolysis, the concentration of liberated formaldehyde in the hydrolyzed solution and mass loss of the cured UMF resins were determined to compare their hydrolytic stability. The hydrolysis of cured UMF resin increased with an increase in the acid concentration, time, and temperature and with a decrease in the smaller particle size. An optimum hydrolysis condition for the cured UMF resins was determined as $50^{\circ}C$, 90 minutes, 1.0 M hydrochloric acid and $250{\mu}m$ particle size. Hydrolysis of the UMF resin cured with different hardener types showed different degrees of the hydrolytic stability of cured UMF resins with a descending order of aluminum sulfate, ammonium chloride, and ammonium sulfate. The hydrolytic stability also decreased as the addition level of ammonium chloride increased. These results indicated that hardener types and level also had an impact on the hydrolytic stability of cured UMF resins.

• 대한화장품학회지
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• 제38권1호
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• pp.51-55
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• 2012

포름알데히드는 그 자체가 보존제로 또는 다른 보존제로부터 유리된 형태로 화장품에 일반적으로 존재한다. 포름알데히드는 낮은 농도로도 민감한 피부 반응을 일으킬 수 있으므로 화장품에서 그 사용을 규제하고 있다. 본 연구에서는 팩 및 마스크와 같은 화장품 114 품목을 시중에서 구입하여 포름알데히드의 함량을 분석하였다. 검사 품목의 36%에서 $0.3{\sim}9.7{\mu}g/mL$ (ppm) 수준의 포름알데히드가 검출되었다. 포름알데히드 유리 보존제를 함유한다고 표시되어 있는 12개 제품의 포름알데히드 함량을 조사하였다. Imidazolidinyl urea를 사용한 화장품 10품목과 1,3-Dimethylol-5,5-dimethylhydantoin (DMDM hyantoin)을 사용한 화장품 2품목에서 평균 $1.7{\mu}g/mL$ (ppm)의 포름알데히드가 검출되었다. 식품의약품안전청 고시 최대 허용 포름알데히드 농도 0.2 % (2,000 ppm)을 고려할 때, 이번 조사에서 분석한 화장품에서는 비교적 낮은 수준의 포름알데히드 함량을 보였다.

• Journal of the Korean Wood Science and Technology
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• 제45권4호
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• pp.409-418
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• 2017

This work attempted to manufacture glued-laminated timber (Glulam) bonded with melamine-urea-formaldehyde (MUF) resin adhesives at various melamine contents from 20% to 50% under high frequency (HF) heating for a very short time. Two preparation methods were employed to prepare MUF resin adhesives with different melamine contents: one-batch method of synthesizing MUF resins in a single batch, and two-batch method of mixing urea-formaldehyde (UF) resin with melamine-formaldehyde (MF) resin that had been synthesized separately. As the melamine content increased, the gelation time and peak temperature of MUF resins decreased. The adhesion performance of plywood showed that the one-batch MUF resin adhesive with 50% melamine content only satisfied the standard requirement of water resistance. Thus, the one-batch MUF resin adhesive with 50% melamine content was applied for bonding wood lamina from four softwood species such as Japanese larch, Korean red pine, Korean pine and Japanese cedar to manufacture Glulam under HF heating. All Glulam samples bonded with the one-batch MUF resin adhesives with 50% melamine content except those from Korean Red Pine satisfied the requirement in water soaking or boiling water delamination test as an exterior grade Glulam. The presence of rosin in Korean Red Pine was believed to be responsible for its poor adhesion. These results showed that the one-batch MUF resin adhesives with 50% melamine content provided acceptable water resistance with exterior grade Glulam manufactured under HF heating.

• 한국산림과학회지
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• 제48권1호
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• pp.40-50
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• 1980

본(本) 연구(硏究)는 합판공장(合板工場)에서 증량제(増量剤)로 사용(使用)하고 있는 도입소맥분(導入小麥粉)을 국내(国內)에서 값싸게 생산(生産)할 수 있는 증량제(増量剤)로 대체(代替)키 위한 가능성(可能性)을 규명하기 위해 실시(実施)되었다. 증량재료(増量材料)로는 주(主)로 삼립부산물(森林副産物)을 이용개발(利用開発)키 위(爲)해서 밀가루, 목분(木粉), 수피(樹皮), 소나무낙엽(落葉), 포푸리낙엽(落葉)을 택(擇)하였으며 각각(各各) $100{\sim}105^{\circ}C$에서 24시간(時間)동안 전건(全乾) 시킨 다음 60~100mesh로 분쇄(粉碎)하였다. 증량방법(増量方法)은 요소수지(尿素樹脂)와 요소(尿素)-melamine 공축합수지(共縮合樹脂)는 소맥분(小麥粉), 목분(木粉), 수피분(樹皮粉), 포푸라낙엽분(落葉粉)을 각각(各各) 10, 20, 30, 50%로 증량(増量)하였으며 수용성석탄산수지(水溶性石炭酸樹脂)는 소맥분(小麥粉), 목분(木粉), 수피분(樹皮粉), 소나무낙엽분(落葉粉)을 각각(各各) 10, 20, 30, 50%로 증량(増量)하였다. 본(本) 연구(硏究)에서 얻은 결론(結論)은 다음과 같다. 1. 요소수지(尿素樹脂)에 있어서는 상태(常態) 및 내수접착력(耐水接着力) 모두 소맥분(小麥粉)을 능가(能加)하는 증량제(増量剤)가 없었다. 2. 요소(尿素)-melamine 공축합수지(共縮合樹脂)에 있어서 접착력(接着力)은 요소수지(尿素樹脂)보다 대체로 모두 양호(良好)하였으나 상태접착력(常態接着力)에 있어서 소맥분(小麥粉)보다 좋은 접착제(接着剤)는 없었다. 3. 요소(尿素)-melamine 공축합수지(共縮合樹脂)에 있어서 내수접착력(耐水接着力)의 경우 10, 20%증량(増量)에서 포푸라낙엽분(落葉粉), 소맥분(小麥粉), 목분(木粉)이 가장 양호(良好)했으며 이들간(間)의 유의적(有意的)인 차이(差異)는 없었다. 4. 수용성석탄산수지(水溶性石炭酸樹脂)의 경우 상태접착력(常態接着力)은 10% 증량(増量)의 경우 소맥분(小麥粉)보다도 소나무낙엽분(落葉粉)이 더 양호(良好)하였으며 20% 증량(増量)의 경우도 유의적(有意的)인 차이(差異)는 없었다. 5. 수용성석탄산수지(水溶性石炭酸樹脂)의 경우 내수접착력(耐水接着力)은 10% 증량(増量)의 경우 목분(木粉)이 소맥분(小麥粉)보다 우수(優秀)했으며 20, 30, 50% 증량(増量)의 경우 목분(木粉) 및 수피분(樹皮粉)은 소맥분(小麥粉)보다도 양호(良好)하였다.

• 한국가구학회지
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• 제22권3호
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• pp.219-229
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• 2011

Sick building syndrome symptoms that are experienced by building occupants may be caused by toxic substances such as formaldehyde and VOCs, which are known to be emitted from building materials and wood composite products such as wood-based panel, furniture, engineered flooring and construction adhesive. In Korea, the use of wood composite products for indoor environments has increased over the last decade. Recently, wood composite products have been installed in approximately 95% of newly constructed residential buildings. The use of these products has resulted in problems related to human health, and consequently a realization about the importance of indoor air quality. In addition, consumer demand is increasing for natural materials because conventional building materials and wood composite products are made by adding urea-formaldehyde resin or they contain formaldehyde-based resin. More recently, many efforts have been made to reduce formaldehyde emission from building materials that laid in the indoor environment. Especially, if conventional formaldehyde-based adhesives are replaced with green adhesives for residential spaces, it is possible to reduce most of the emission amounts of formaldehyde in indoor environments. In line with this expectation, many researches are being conducted using natural materials such as tannin and cashew nut shell liquid (CNSL). This study discussed the affects and possibilities of green adhesives to reduce formaldehyde emission in indoor environments.

• Journal of the Korean Wood Science and Technology
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• 제16권3호
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• pp.17-21
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• 1988

In order to investigate the extending effects on urea-formaldehyde resin- or phenol- formal- dehyde resin- glued keruing plywood, hot pressing temperatures were controlled to 110, 140, 170 and $200^{\circ}C$. As the extender, wheat flour, persimmon bark powder, chestnut bark powder, the equivalently- extended with the above three powders, and diatomite powder were respectively mixed with 5, 10, 15 and 20% ratios to the resin liquid, and also with these the no- extended was allowed. Based on the measured bonding strength, the conclusions were drawn: 1. In the urea- formaldehyde resin, extending effects on the bonding strength were in the order of wheat flour, the equivalently- extended with the wheat flour, persimmon- and chestnut bark powder, persimmon bark powder, chestnut bark powder. In the phenol- formaldehyde resin, the effects in the order of wheat flour, persimmon bark powder, diatomite powder, chestnut bark powder were resulted in. Specifically, superior bonding strength to the no-extended were given with the wheat flour and persimmon bark powder. 2. On the whole, the bonding strength decreased gradually, as the hot pressing temperature increased except for the diatomite powder extending.