• 한국전기전자재료학회논문지
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• 제28권12호
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• pp.813-820
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• 2015

We have studied commercialization and process optimization of protective film on transparent conductive coated substrate, nano silver on flexible PET (poly ethylene terephthalate), by means of roll-to-roll micro-gravure coater. Nanosilver on flexible PET substrate is potential materials to replace ITO (indium tin oxide). Protective film is most important to maintain unique silver pattern on top of transparent PET. PSA pressure sensitive adhesives) was developed solely for nano silver on PET and protective film was successfully laminated. We have optimized all process conditions such as coating thickness, line speed and aging time & temperature via experimental design. Transparent conductive film and its protective film developed in this research are commercially available at this moment.

• 한국표면공학회지
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• 제48권5호
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• pp.218-226
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• 2015

The goal of this study is to investigate a metal cladding that contains SiC composites as a protective layer and analysis the characteristics of the specimens on high temperature oxidation To make SiC composites, the current process needs a high temperature (about $1100^{\circ}C$) for the infiltration of fixing materials such as SiC. To improve this situation, we need a low temperature process. In this study, we developed a low temperature process for making SiC composites on the metal layer, and we have made two kinds: cladding with protective SiC composites made by polycarbosilane(PCS), and a PCS filling method using supercritical carbon dioxide. A corrosion test at $1200^{\circ}C$ in a mixed steam and Ar atmosphere was performed on these specimens. The result show that the cladding with protective SiC composites have excellent oxidation suprression rates. This study can be said to have developed new metal cladding with enhanced durability by using SiC composite as protective films of metal cladding instead of simple coating film.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.120-129
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• 1997

The fire protective coating can reduce certain damages in case of fire, also conserve energy by thermal insulation and prevent corrosion and errosion in normal daily life by means of blocking thermal transfer, that were generally made of organic, inorganic and metallic materials as adiabatic coating. In case of inorganic material such as soluble silicate, it produces less toxic substances which are exposed to Ore, and have a plenty of raw material. Also inorganic thermal insulator is good in heat resistance. To develope such a excellent inorganic thermal insulator, the study of fire protective coating using the alkali silicate is necessary The principle of intumescence for alkali silicate is from rapid evolution of water in the coating material, the quantity of water in it is of course influenced on the degree of intumescence. The phenomenon of intumescence in ternary silicate is increased as the radius of ion is bigger, and this is caused by evolution of so many kinds of water. The individual degree of intumescence is ordered like this ; $K^+$ > $Na^+$ > $Li^+$ . The best protection effect is similarity found to intumescence of ternary silicate. The result of X-ray diffraction analysis indicates that $KHSi_2O_5$ is an important ingredient in K-silicate.

• 융합정보논문지
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• 제9권10호
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• pp.87-93
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• 2019

치유 물질인 아마인유에 형광 물질을 소량 혼합한 혼합물을 코어 성분으로 하여 마이크로캡슐을 제조하였다. 이 마이크로캡슐을 코팅재 조성물에 균일하게 분산시켜 모르타르 표면에 도포함으로써 지기치유 보호코팅재를 제작하였다. 이 코팅재에 약 $100{\mu}m$ 폭의 스크래치 또는 균열 손상을 발생시킨 후 자외선을 조사하면서 관찰한 결과, 캡슐 함량이 증가할수록 형광 발광의 범위가 증가하였고, 20wt% 이상의 캡슐을 함유한 코팅재에서는 손상 부위가 치유물질로 거의 채워진 모습을 나타내었다. 물흡수도 시험 결과 20wt% 이상의 캡슐을 함유한 코팅재는 약 85%의 치유효율을 보였다. 손상 부위에서 나타나는 형광은 3m의 거리에서도 용이하게 식별되었다. 본 연구결과는 콘크리트 보호를 위한 마이크로캡슐형 자기치유 코팅재의 치유기능을 육안으로 용이하게 확인하는데 도움을 줄 것으로 기대된다.

• 한국안전학회지
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• 제13권4호
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• pp.206-212
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• 1998

The water permeation in protective coatings, which may greatly influence the corrosion protective property of these coatings, was studied using the electrochemical impedance spectroscopy technique. During the absorption of water in protective coatings immersed in electrolyte solution, the change of coating capacitance with concentration of electrolyte was determined from impedance measurements. When water absorption or desorption of coatings occured by exposing the coatings to electrolyte solutions of different concentration, increase in impedance caused by desorption of water was found to be higher in the case of thicker film. The amount of water absorbed in coatings changed with concentration of electrolyte. The water taken up in coatings from the solution of lower electrolyte concentration was deserted by contact with the solution of higher concentration. The uptake of water in protective coatings varied depending on the type of coating ingredient especially binder.

• Corrosion Science and Technology
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• 제11권5호
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• pp.165-172
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• 2012

The corrosion resistance of epoxy-coated carbon steel was evaluated. The carbon steel surface was subjected to different treatment methods such as steel grit blasting with different size, steel shot ball blasting and power tool treatment. To study the effect of the treatments, the topology of the treated surface was observed by optical 3D microscopy and a pull-off adhesion test was conducted. The corrosion resistance of the epoxy-coated carbon steel was further examined by electrochemical impedance spectroscopy (EIS) combined with hygrothermal cyclic testing. The results of EIS indicated that the epoxy-coated carbon steel treated with steel grit blasting showed an improved corrosion resistance compared to untreated epoxy-coated surfaces or surfaces subjected to shot ball blasting and power tool treatments.

• 대한조선학회 특별논문집
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• 대한조선학회 2013년도 특별논문집
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• pp.66-72
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• 2013

The demand for an ice class ship is rising expected to rise according to the increase of energy consumption and the opening of arctic sea routes. Ice class ship should be designed to cope with the severe environmental conditions of arctic sea such as a high mechanical impact and abrasion damage, caused by pack ice, ice bergs and low temperature. The ice class ship hulls are coated with an anti-abrasion and low friction coating such as a solvent free epoxy or high solid-volume epoxy. These coatings require two-component heating pump and a high grade surface preparation. In this study, the coating performances for the arctic vessels, such as puncture absorbed energy, abrasive wear loss, friction coefficients and impact absorbed energy were evaluated. Based on this study, a proper coating performance specification for the arctic vessels was proposed and coating selection guideline in terms of coating performance and workability was also established.

• Tribology and Lubricants
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• 제33권6호
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• pp.275-281
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• 2017

In this work, we have fabricated anodic aluminum oxide (AAO) with ordered nanoscale porosity through an anodization process. We deposited gold and nano-organic thin films on the porous AAO surface to protect its structure and reduce friction. We investigated the tribological characteristics of the porous AAO with respect to the protective surface coatings using tribometers. While investigating the frictional characteristics of the samples by applying normal forces of the order of micro-Newton, we observed that AAO without a protective coating exhibits the highest friction coefficient. In the presence of protective surface coatings, the friction coefficient decreases significantly. We applied normal forces of the order of milli-Newton during the tribotests to investigate the wear characteristics of AAO, and observed that AAO without protective surface coatings experiences severe damage due to the brittle nature of the oxide layer. We observed the presence of several pieces of fractured particles in the wear track; these fractured particles lead to an increase in the friction. However, by using surface coatings such as gold thin films and nano-organic thin films, we confirmed that the thin films with nanoscale thickness protect the AAO surface without exhibiting significant wear tracks and maintain a stable friction coefficient for the duration of the tribotests.

• Corrosion Science and Technology
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• 제7권4호
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• pp.219-223
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• 2008

In 2006, as a means to minimize early corrosion failure of ships, thus to enhance marine safety, International Maritime Organization (IMO), proposed a mandatory regulation for Performance Standards for the Protective Coatings (PSPC) for ballast tanks of newly built ships to satisfy 15 years of target useful life. In this regulation, several unprecedented strict rules are adopted as minimum, mandatory requirements for protective coatings of ship's water ballast tanks, and all type of ships sailing international sea are subjected to this regulation which is to be effective as early as June of 2008. The PSPC addresses many technical issues in the areas of surface pretreatment (primary and secondary), coating materials, coating application procedure and inspection as well as necessary documentation. The PSPC rules are new and unproven concepts, which calls for rigorous incorporation of reality-based evidences currently available, since there are no practical experiences in terms of the validity of the PSPC rules. There has been much controversy surrounding these regulations and considerable effort has been made by both shipyards and ship owners alike to achieve a performance standard for ballast tank coatings, which is acceptable to all. In this paper, the background and overview of the PSPC rules are given, and several issues in the PSPC are reviewed as a base to achieve robustness of the proposed PSPC, which will serve as a means to minimize early corrosion and to ensure 15 year target useful life of ships.

• 전기화학회지
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• 제1권1호
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• pp.55-59
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• 1998

방식도막의 수명에 가장 큰 영향을 미치는 물의 흡수과정을 quartz crystal microbalance법 및 임피던스 원리를 이용하여 연구하였다. 도막에 있어서 물의 흡수량과 전해질 농도 변화에 따른 도막의 capacitance를 조사하였다 방식도막에 대한 물의 흡수는 삼투압 작용에 의해서 이루어지고, 흡수 초기단계에서는 도막두께가 얇을수록 흡수량이 많은 것을 알 수 있었다 그리고 도막을 구성하고 있는 수지의 종류 및 결합 가교밀도에 따라서 흡수성이 큰 영향을 받는다는 것을 알 수 있었다. 또한 방식도막에 있어서는 접촉하는 전해질 용액의 농도 변화에 따라 흡$\cdot$탈수 현상이 발생하였으며, 같은 종류의 도막이라도 도막두께가 얇을수록 탈수현상에 따른 capacitance의 증가폭이 큰 것으로 나타났다