• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2005년도 춘계학술대회 논문집
• /
• pp.33-36
• /
• 2005

Colloidal Silica(CS)/silane sol solutions were prepared in variation with synthesizing parameters such as ratio of CS to silane and reaction time. In the case of LHSA CS/tetramethoxysilane(TMOS)/methyltrimethoxysilane(MTMS) CS/silane sol, coating film had stable contact angle with increasing reaction time excepting for 48hours. Also, the LHSA CS/TMOS/MTMS coating film had more enhanced flat surface with increasing the amount of MTMS and increasing reaction time. In the case of thermal stability, thermal dissociation of LHSA CS/MTMS sol did not occur up to $550^{\circ}C$.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
• /
• pp.445-446
• /
• 2007

The use of plastic substrates enables new applications, such as flexible display devices, and other flexible electronic devices, using low cost, rollto-roll (R2R) fabrication technologies. One of the limitations of polymeric substrate in these applications is that oxygen and moisture rapidly diffuse through the material and subsequently degrade the electro-optical devices. GE Global Research (GEGR) has developed a plastic substrate technology comprised of a superior high-heat polycarbonate (LEXAN(R)) substrate film and a unique transparent coating package that provides the ultrahigh barrier (UHB) to moisture and oxygen, chemical resistance to solvents used in device fabrications, and a high performance transparent conductor. This article describes the coating solutions for polycarbonate (LEXAN(R)) films and its compatibility with OLED device fabrication processes.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
• /
• pp.83-86
• /
• 1998

Ferroelectric PZT(40/67)/PZT(60/40)heterolayered thin films were Prepared by the alkoxide-based Sol-Gel method. PZT(40/60) and PZT(60/40) stock solutions were made and spin-coated on the P7Ti/Si02/Si substrate alternately. These PZT(40/60) and PZT(60/40) films were dried at 300$^{\circ}C$ for 30min to remove organic materials and were sintered at 650$^{\circ}C$ for 1 hour to crystalize into a perovskite structure. The coating and heating procedure were repeated 6 times to form heterolayered films. Increasing the number of coating, coercive field was decreased. The relative dielectric constant, loss, remanent polarization and coercive field of the 4-coated PZT heterolayered were 1200, 4.1[%], 30.794[${\mu}$C/㎡] and 147.22[kV/cm], respectively.

• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2008년도 추계학술대회 초록집
• /
• pp.155-157
• /
• 2008

High velocity oxy-fuel (HVOF) thermal spraying coating has been used widely throughout the last 60 years mainly in defense, aerospace, and power plants. Recently this coating technique is considered as a promising candidate for the replacement of the traditional electrolytic hard chrome plating (EHC) which pollutes the environment and causes lung cancer by toxic hexa-valent $Cr^{6+}$. In this study, two kinds of cermet coatings, WC-CoCr and WC-CrC-Ni, are formed by HVOF spraying. The corrosion and electrochemical properties are evaluated by polarization tests in 3.5 wt% solutions.

• 방사성폐기물학회지
• /
• 제21권1호
• /
• pp.115-147
• /
• 2023

The Fukushima accident in 2011 revealed some major flaws in traditional nuclear fuel materials under accidental conditions. Thus, the focus of research has shifted toward "accident tolerant fuel" (ATF). The aim of this approach is to develop fuel material solutions that lead to improved reactor safety. The application of protective coatings on the surface of nuclear fuel cladding has been proposed as a near-term solution within the ATF framework. Many coating materials are being developed and evaluated. In this article, an overview of different zirconium-based alloys currently in use in the nuclear industry is provided, and their performances in normal and accidental conditions are discussed. Coating materials proposed by different institutions and organizations, their performances under different conditions simulating nuclear reactor environments are reviewed. The strengths and weaknesses of these coatings are highlighted, and the challenges addressed by different studies are summarized, providing a basis for future research. Finally, technologies and methods used to synthesize thin-film coatings are outlined.

• 한국초전도ㆍ저온공학회논문지
• /
• 제10권1호
• /
• pp.6-9
• /
• 2008

We have investigated the MOD process successfully for the fabrication of the YBCO thick film on the $LaAlO_3$(001) single crystalline substrate. The cracking problem in YBCO thick film, a serious problem in the conventional TFA-MOD method, could be overcome with a careful control of precursor materials. Thus coating solution was prepared for the YBCO thick film by using fluorine-free precursor material. The precursor solutions were coated on the LAO(001) single crystalline substrate using the dip coating method, calcined at the temperature up to $500^{\circ}C$, and fired at various high temperatures for 2 h in a reduced oxygen atmosphere. Optimally processed YBCO thick film exhibited high critical current($I_c$) over 200 A/cm-width at 77K in self-field.

• 한국응용과학기술학회지
• /
• 제36권2호
• /
• pp.531-540
• /
• 2019

친수성 및 소수성 나노실리카를 tetraethyl orthosilicate(TEOS)를 커플링제로 사용하여 유리 표면에 거친 스파이크 구조 형성과 반응성 hydroxyl기를 동시에 도입한 후 불소를 함유한 실란으로 2차 코팅처리하여 궁극적으로 발수성 유리 표면 형성의 최적 조건을 확립하는 연구를 수행하였다. 소수성 나노실리카인 실리카 에어로졸을 이용한 초소수 도막의 형성은 나노실리카 표면에 반응성인 -OH기가 존재하지 않아 내구성이 있는 소수성 도막을 형성할 수 없었다. 이에 반하여 친수성기를 가진 나노실리카와 가수분해된 TEOS를 포함하는 코팅액 이용하여 유리 표면을 1차 코팅한 후 2차로 trichloro-(1H,1H,2H,2H)perfluorooctylsilane(TPFOS) 용액으로 코팅하여 $150^{\circ}$ 이상의 수접촉각을 가지는 초소수 표면을 제조하였으며, $1^{\circ}$ 이하의 물 슬라이딩각을 보여 초발수성도 동시에 가지고 있었다. 이에 덧붙여 친수성 나노실리카의 함량이 증가할수록 광투과도가 감소하였으며, TPFOS 용액에 의해서도 광투과도가 감소하였다. 코팅된 유리시편의 내구성 50회 문지름까지는 초소수성을 유지하였으나, 200회 문지름에서는 단지 소수성만을 유지하였다. 결론적으로 최적의 코팅액의 조건은 친수성 나노실리카의 함량이 0.3 g인 HP3 코팅액을 2회 코팅한 후 2차로 TPFOS 용액으로 코팅하는 것이었다. 이렇게 제조된 코팅액은 광투과도가 중요한 솔라셀의 표면 처리제로 사용이 가능할 것으로 판단된다.

• Applied Biological Chemistry
• /
• 제12권
• /
• pp.89-97
• /
• 1969

Plastic 용액(溶液)을 청과물표피(靑果物表皮)에 피복(被覆)하던 수분증산(水分蒸散)의 억제(抑制)와 gas대사(代謝)의 조절(調節)로 저장목적(貯藏目的)을 효과적(效果的)으로 달성(達成)할수 있다는 기도(企圖)아래 적당(適當)한 P.V.C. powder의 색출(索出) Coating의 방법(方法) 유기용매(有機溶媒)의 선택(選擇) 농도(濃度)와 침지시간(浸漬時間)및 저장효과(貯藏效果)에 대(對)하여 시험(試驗)을 수행(遂行), 다음과 같은 결과(結果)를 얻었다. 1) P.V.C powder 222 및 443은 사과 Coating에 모두 적합(適合)하나 433이 광택(光澤)에서 더욱 우수(優秀)하였다. 2) Coating의 방법(方法)은 침지법(浸漬法)이 단시간내(短時間內) 다량(多量) Coating에 적합(適合)하며 Ventillator의 사용(使用)은 유기용매(有機溶媒)의 휘발(揮發)을 촉진(促進)하였다. 3) 유기용매(有機溶媒)는 Acetone 과 Methyl ethyl ketone 이 저장목적(貯藏目的)에 저합(適合)하나 식미(食味)를 고려(考慮)할때 Acetone이 실용적(實用的)이라고 생각한다. 4) 용액(溶液)의 농도(濃度)는 10, 5, 4, 1, 0.5%의 순위(順位)로 선도보장(鮮度保藏)이 우수(優秀)하였으며 15%는 Coating 1 주일후(過日後)부터 발효현산(醱酵現象)이 일어났다. 5) 침지시간(浸漬時間)은 4분(分) 2분(分) 1분(分) 10초(秒)의 순위(順位)로 보장성(保藏性)이 우수(優秀)하였으나 심미(食味)를 고려(考慮)하여 $1{\sim}2$분간침지(分間浸漬)이 실용적(實用的)이라 생각한다. 6) 선도(鮮度)의 보장(保藏)은 Control구(區)가 고온저장(高溫貯藏)에서 12일후(日後)부터 점차(漸次) 상품가치(商品價値)를 상실(喪失)한데 비(比)하여 Coating 구(區)에서는 48 일간(日間) 선도(鮮度)가 보장(保藏)되어 현저(顯著)한 저장효과(貯藏效果)를 보였다. 7) 중량감소율(重量滅少率)은 고온저장(高溫貯藏)에서 Control 구(區)가 $10{\sim}13%$감소(減少)한데 비(比)하여 10%에서 1분간침지(分間浸漬)한 것은 $3.5{\sim}4.6%$ 4분간침지(分間浸漬)한 것은 $2.9{\sim}3.0%$의 감소율(滅少率)을 나타냈다. 8) 호흡(呼吸)의 변화(變化)는 Coating구(區)에서 $CO_2$의 방출량(放出量)이 낮았으며 수용성당(水溶性糖), 환원당(還元糖)및 pH는 Coating에 의(依)한 변화(變化)가 거의 없었다. 9) 식미(食味) Test 결과(結果)는 Coating 직후(直後)에는 Control 구(區)에 비(比)하여 저조(低調)하였으나 저장말기(貯藏末期)에는 Coating 구(區)의 평점(評點)이 높았으며 특(特)히 Acetone 용매(溶媒)를 사(使用)한 것이 우수(優秀)하였다.

• 한국염색가공학회지
• /
• 제23권4호
• /
• pp.227-232
• /
• 2011

Zein is a hydrophobic protein produced from maize and has great potential in a number of industrial applications, such as food, food coating and food packaging. To obtain suitable electrospinning conditions for thinner and uniform zein nanofiber mats, a series of experiments was conducted on various volume ratios (v/v) of ethanol/water solutions with different zein concentrations. The prepared zein nanofiber mats were characterized by field emission scanning electron microscopy and contact angle measurements. Uniform zein fibers with a average diameter in the nanometer scale (300~500 nm) could be prepared from 30 wt.% zein in 7/3 (v/v) ethanol/water solutions.

• 한국결정학회지
• /
• 제14권2호
• /
• pp.67-72
• /
• 2003

Graphite powders were coated with ZrO₂ by the controlled hydrolysis of a DI water, ethanol and DI water+ethanol solutions. The hydrolysis process was carried out with temperature control because of the low wettability of Zr ions to the surface of the graphite. PVA was added to the solution for the enhancement of metal ion adsorption. The surface of the graphite powders coated with ZrO₂ was observed by SEM and TEM. There are two types of ZrO₂ particles with the condition of ZrOCl₂°§8H₂O aqueous solutions were used; (a) primary particles a few nm in size and (b) secondary particles with ∼0.1 ㎛ size were obtained. The graphite powders coated in 50% ethanol-50% DI water solution of Zr(SO₄)₂ㆍ4H₂O have the relatively uniform coating layer and the starting temperature of oxidation was 100℃ higher than the raw graphite.