• 한국포장학회지
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• 제25권1호
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• pp.1-10
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• 2019

이번 연구에서는 식품 포장재로 많이 활용하고 있는 산소 고차단성 필름 두 종류의 환경 영향을 평가하는 것이었다. Table 4의 경우 환경 영향 모델에 따라 계산된 Traditional film과 New film의 각 환경 영향 범주 별 비교 값 및 이러한 차이를 보인 가장 영향력 있는 공정을 설명하였다.

• Korean Chemical Engineering Research
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• 제61권3호
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• pp.439-445
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• 2023

본 연구에서는 질산은을 PVA로 환원시켜 은 나노입자를 합성하였으며, 얻어진 은 나노입자에 Carboxymethyl cellulose (CMC)를 첨가시켜 제조된 용액을 PET 기재 위에 코팅함에 의해 항균 특성과 김서림 방지 기능을 갖는 코팅 도막을 제조하였다. 코팅 도막을 80 ℃의 수증기와 접촉 시 코팅되지 않은 PET 기재는 김서림 발생으로 인한 빛의 산란이 발생해 흐려진 결과를 보인 반면에 CMC가 첨가된 은 나노졸로 코팅된 도막은 수증기와의 접촉에도 불구하고 투명한 상태를 유지하여 김서림 방지 기능이 우수하였다. 또한 코팅 도막의 항균성을 그램 양성균인 포도상구균과 그람 음성균인 대장균에 대해 필름 밀착법으로 측정하였다. 코팅되지 않은 PET 기재에서는 많은 포도상구균과 대장균의 집락이 관찰된 반면에 은 나노졸로 코팅된 도막은 포도상구균과 대장균의 성장이 크게 억제되어 항균 효과가 우수하였다.

• 공업화학
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• 제26권4호
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• pp.400-405
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• 2015

Tetraethylorthosilicate (TEOS)를 전구체로서 이용하여 제조된 기존의 반사방지(AR; anti-reflective) 코팅막은 대부분 수분을 쉽게 흡수할 뿐만 아니라 낮은 내마모성을 갖는다. 본 연구에서는 AR 코팅막의 투과율, 소수성 및 내마모성을 향상할 목적으로 전구체로서 methyltrimethoxysilane (MTMS)를 사용하고 불소 실란, 산 촉매, 염기 촉매 및 산-염기 2단계 촉매를 첨가하여 다양한 AR 코팅막을 제조하였다. 제조된 AR 코팅막은 UV-Vis, 접촉각 측정기, AFM, 연필경도 및 부착성 시험을 통해 특성을 분석하였다. 그 결과, 경화온도가 $300^{\circ}C$일 때 코팅되지 않은 유리 기판의 투과율은 90.5%인 반면, AR 코팅된 유리 기판의 투과율은 94.8%로 증가하였다. 불소 실란을 첨가한 경우, 소수성이 크게 향상되었음을 나타내듯이 AR 코팅막 표면에서의 접촉각은 $96.3^{\circ}$에서 $108^{\circ}$까지 증가하였다. AR 코팅막의 내마모성은 산 촉매에 의해 향상되었으며, 그것의 투과율은 염기 촉매에 의해 증가하였다. 산-염기 2단계 촉매 반응에 의해 제조한 AR 코팅막의 경우, 상승 효과에 의해 촉매의 도입 없이 제조된 AR 코팅막과 비교하여 투과율 및 내마모성이 향상되었다.

• 한국분무공학회지
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• 제18권3호
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• pp.146-154
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• 2013

The flow of a liquid film on spin coating is investigated in the case that the fixed volume of a liquid is placed on the center of a stationary disk. Thin film equations that are well approximated when the characteristic length in the vertical direction is much smaller than that in the radial direction (${\varepsilon}{\ll}1$) and have already been proposed in the work of T.-S. Kim & M.-U. Kim (2009), are used. The differential equation that governs the free surface of a liquid when ${\varepsilon}{\ll}1$ and ${\varepsilon}Re{\ll}1$ is also derived. The basic flow is analyzed using the thin film equations and their results are compared to the results of Navier-Stokes equations.

• 반도체디스플레이기술학회지
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• 제13권1호
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• pp.91-95
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• 2014

(F,Ga) co-doped ZnO thin film on glass substrate was fabricated via a simple non-alkoxide sol-gel spin-coating. Contrary to the F single doped ZnO thin film, the (F,Ga) co-doped thin film showed a significant reduce in electrical resistivity after a second post-heat-treatment in reducing environment. The resulting decrease in electrical resistivity with Ga co-doping is considered to be resulted from the increases both carrier density and mobility. The optical transmittance of the (F,Ga) co-doped thin film in the visible range showed higher transmittance with Ga co-doping compared with F single doped ZnO thin film.

• 한국표면공학회지
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• 제46권6호
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• pp.277-282
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• 2013

This study is an experimental attempt to confirm the binder effect of zeolite coating on glass plate by heat treatment. As a result, zeolite was successfully formed with low concentratios of pressure, whose concentration was effective in 10% or more for thin film zeolite coating. And as the content of the binder (TEOS) in mixed coating solution was higher, the zeolite was fastened better on the surface. Above 5% content of the binder in the coating solution, TEOS hindered zeolite synthesis of the precursor and brought to zeolite capacity decrease. Furthermore, when the concentration of the precursor, sedimentation rate of the precursor was higher and the coating efficiency is reduced thereby. Therefore, the most effective concentrations of the precursor and TEOS in the coating solution was 10% and 5%, respectively. It was concluded that zeolite coating is produced by heat treatment method after dipping without hydrothermal synthesis.

• 한국분말재료학회지
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• 제18권5호
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• pp.423-429
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• 2011

Thermoelectric-thick films were fabricated by using a screen printing process of n and p-type bismuth-telluride-based pastes. The screen-printed thick films have approximately 30 ${\mu}m$ in thickness and show rough surfaces yielding an empty gap between an electrode and the thick film. The gap might result in an increase of an electrical resistivity of the fabricated thick-film-type thermoelectric module. In this study, we suggest a conductive metal coating onto the surfaces of the screen-printed paste in order to reduce the contact resistance in the module. As a result, the electrical resistivity of the thermoelectric module having a gold coating layer was significantly reduced up to 30% compared to that of a module without any metal coating. This result indicates that an introduction of conductive metal layers is effective to decrease the contact resistivity of a thick-film-typed thermoelectric module processed by screen printing.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.256-256
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• 2013

Carbon nanotubes (CNT) / polyvinylidene fluoride (PVDF) piezoelectric composite films for nanogenerator devices were fabricated by spray coating method. When the CNT/PVDF mixture solution passes through the spray nozzle with small diameter by the compressed nitrogen gas, electric charges are generated in the liquid by a triboelectric effect. Then randomly distributed ${\beta}$ phase PVDF film could be re-oriented by the electric field resulting from the accumulated electrical charges, and might be resulted in extremely one-directionally aligned ${\beta}$ phase PVDF film without additional electric field for poling. X-ray diffraction patterns were used to investigate crystal structure of the CNT/PVDF composite films. It was confirmed that they revealed extremely large portion of the ${\beta}$ phase PVDF crystalline in the film. Therefore we could obtain the poled CNT/PVDF piezoelectric composite films by the spray coating method without additional poling process. Charge accumulation and resulting electric field generation mechanism by spray coating method were shown in Fig. 1. The capacitance of the CNT/PVDF films increased by adding CNTs into the PVDF matrix, and finally saturated. However, the I-V curves didn't show any saturation effect in the CNT concentration range of 0~4 wt%. Therefore we can control the performance of the devices fabricated from the CNT/PVDF composite film by adjusting the current level resulted from the CNT concentration with the uniform capacitance value.

• 한국정밀공학회지
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• 제30권6호
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• pp.589-595
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• 2013

Solution processed conjugated molecules enable to manufacture various electronic devices by unconventional and cost effective patterning methods as screen or gravure printing. Spin-coating is the most popularly used method to form conjugated polymeric film for various electronic devices. The coating method has certain disadvantages such as a large amount of unwanted wastes, difficulty forming a film with a large area, and impossible to apply roll-to-roll manufacturing. We present here a promising alternative coating method, bar-coating for conjugated polymer film and OLED with the bar coated light emitting layer. In this papers, we show atomic force microscope images of spin- and bar-coated Poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo[2,1,3]thiadiazol-4,8-diyl)] (F8BT) films on substrate. The bar-coated film showed a slight lower RMS roughness (1.058 [nm]) than spin-coated film (1.767 [nm]). It means the bar-coating is suitable method to form light emitting layers in OLEDs. By using bar-coating process, an OLED obtained with 4.7 [cd/A] in maximum current efficiency.

• 한국환경과학회지
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• 제30권12호
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• pp.1041-1051
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• 2021

The purpose of this study was to identify for extenders, adhesives, colorants, and fungicides suitable for the production of high-quality film-coated seeds of Chinese cabbage. In addition, the effect of various additives used for film coating on the germination of coated seeds and seedling vigor was investigated to establish appropriate treatment conditions for film coating efficiency. The germination rate and germination speed in Chinese cabbage film-coated seeds did not differ significantly depending on the type and concentration of the extender, while the use of Talc resulted in superior granulation capacity and adhesion of the seed coat in comparison to Zeolite. There was no significant difference in the germination rate depending on the type of adhesive used for film coating of Chinese cabbage seeds, but the germination rate was slightly slower in the film-coated seeds using carboxymethyl cellulose as an adhesive. On the other hand, the seeds coated with a film using 1% PVA as an adhesive not only maintained hardness enough to withstand external pressure, but also showed a high germination rate. In addition, the suitable disinfectant for film coating was venoram, and the treatment concentration was good at 250 mg·L^-1. The type of colorant used in the film-coated seeds of Chinese cabbage did not significantly affect the germination rate, germination speed, and seedling vigor. The seeds film-coated using the liquid colorant were superior in appearance to the seeds film-coated with the solid colorant, which implies the possibility of reduction in the manufacturing costs by using the water-soluble paints as colorants for film-coated seeds.