• 한국세라믹학회지
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• 제45권10호
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• pp.610-617
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• 2008

Multi-walled carbon nanotube(CNT) reinforced hydroxyapatite composite coating with a thickness of $5{\mu}m$ has been successfully deposited on Ti substrate using aerosol deposition(AD). The coating had a dense microstructure with no cracks or pores, showing good adhesion with the Ti substrate. Microstructural observation using field-emission scanning electron microscopy(FE-SEM) and transmission electron microscopy(TEM) showed that CNTs with original tubular morphology were found in the hydroxyapatite-CNT(HA-CNT) composite coating. Measurements of hardness and elastic modulus for the coating were performed by nanoindentation tests, indicating that the mechanical properties of the coating were remarkably improved by the addition of CNT to HA coating. Therefore, HA-CNT composite coating produced by AD is expected to be potentially applied to the coating for high load bearing implants.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.279-279
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• 2013

We report on the preparation of polydimethylsiloxane (PDMS) coated multi-walled carbon nanotubes (MWNTs) followed by their dispersion in various solvents. To disperse MWNTs without acids of surfactants, which are the commonly used methods, hydrophobic PDMS coating was selected. It was determined that the PDMS coated MWNTs are more dispersed in diverse solvents such as dimethyl formamide (DMF) and acetone than bare MWNTs. In case of DMF solvent, dispersion of MWNT was improved by 40 % upon PDMS-coating of MWNT, which was confirmed by UV/Vis absorption spectroscopy. In this work, the PDMS coated MWNTs dispersed solution was also used for the fabrication of film, which is conductive, transparent and superhydrophobic because of the reduced aggregation and increased water repellency of MWNTs.

• 펄프종이기술
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• 제48권1호
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• pp.27-33
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• 2016

This study was carried out in order to investigate the effect of binder properties in pre-coating layer on the characteristics of top-coating layer and print mottle of coated paper. Four different latices were used as a binder in pre-coating layer, and coating color prepared with a same formulation was applied for top-coating. The properties and print mottle of coated paper were evaluated. It was found that glass transition temperature (Tg) was the important factor to control the properties of pre- and top-coating layer. PPS roughness of coated paper was decreased and paper gloss was increased with applying binder which has lower Tg. Properties of top-coating layer were affected by the binder used in pre-coating layer. Print mottle of coated paper was improved with using binder which has lower Tg in pre-coating layer. These results indicate that final printability and properties of top-coating layer can be improved with using suitable binder in pre-coating layer.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2001년도 춘계학술발표논문집
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• pp.78-78
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• 2001

현재 Lab Coating은 실험의 정확성 및 재현성을 위해 기존의 Hand Coating에서 탈피하여 Mayor Coater나 CLC(Cylindrical Laboratory Coated) 등을 사용하여 주로 진행된다. Lab Coater로는 현재 가장 진보된 장비라고 할 수 있는 CLC의 경우 속도와 metering 방식 등에서 현장과 유사한 조건을 재현할 수 있다. 그러나 CLC를 사용하여 Multi Layer C Coating을 실시할 경우 원하는 도공량을 얻기 위해서는 상당한 시간과 노력이 필요하며 특히 Triple Coating의 경 우는 더 힘 든 과정 을 거 쳐 야 한다. 그래서 본 연구에서는 도공량 변화 및 Color Formulation 변경에 의한 물성변화를 측정 하여 Triple Coating에서 두 인자가 각각의 품질에 미치는 영향을 비교 분석하여 어느 정도 도공량 변화가 Color Formulation 변화에 상응하는 영향을 주는지를 파악하고자 하였다.코팅은 CLC 6000을 이용하여 실시하였으며, rod와 blade를 사용한 Triple coating을 5가 지 경우의 Color Formulation에 대하여 실시하였다. 변화시켜 코팅한 후 도공량에 따른 백지물성 관계를 분석한 결과 백색도, 평활도, 거칠음도, 투 기도,2도 trap, Set-Off, Dr${\gamma}$ pick은 총도공량과 강한 상관관계를 보였고, 광택도와 K&N은 총도공량보다는 Top 코팅량과 강한 상관 관계를 보였다. 동일한 코팅칼라를 이용하여 인쇄물성을 고찰하였다. 도공량과 물성의 그러나 동일한 코팅칼라를 사용하여 얻어진 일련의 상관성은 Color Formulation이 변경 되었을 경우 전혀 발견할 수 없었다. 즉 Triple Coating에서 코팅칼라 변경이 품질에 미치는 영향은 도공량 변화에 비해 절대적이어서 몇십%의 현을 억제하지는 못한다는 결론을 도출할 수 있었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 춘계학술대회 논문집
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• pp.783-791
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• 2000

Increasing demands in productivity are propelling the development of new manufacturing methods like hard machining, high speed cutting (HSC) or machining of difficult to machine materials. In these processes the toois are subjected to very severe mechanical, tribological and thermal loads. They fail prematurely by abrasion, cratering, edge breakage and cold welding. The performance of such tools will be enhanced by better and more wear resistant coatings. The development of these new coatings shows a clear trend towards complex multi-component and multi-layer configurations. TiAIN multilayer coating belongs to these coatings for the new cutting tool generation. This paper tries to explain the benefits of the new coatings. TiAIN multilayer coating offers the following advantages: reduction of manufacturing costs. boost productivity, and lower coolant procurement, conditioning and disposal costs.

• 펄프종이기술
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• 제48권2호
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• pp.61-67
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• 2016

This study was carried out in order to investigate the effect of pigment properties in a pre-coating layer on the characteristics of a top-coating layer and the print mottle of the coated paper. Five different pigments were applied for this study as raw materials for the pre-coating layer. The properties and print mottle of the coated paper samples were evaluated according to the coating color formulation. Type of pigments appliied in a pre-coating layer was one of the most important factor to control the properties of pre and top coating layer. Surface properties of pre and top coated paper were improved by blending GCC which had smaller particle size, with clay. Properties of a top-coating layer was affected by the pigment properties used in the pre-coating layer. It was found that print mottle of coated paper can be improved by replacing part of GCC with smaller particle size GCC or clay in pre-coating layer.

• Corrosion Science and Technology
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• 제19권5호
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• pp.265-280
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• 2020

External corrosion of buried pipes can be controlled using both coating and cathodic protection. However, deterioration of the coating can occur due to several reasons. The detection reliabilty of coating flaw detection methods is affected by interference such as metal objects connected to rectifiers and copper grids. When performing parallel direct current voltage gradient (DCVG) inspection, a sine wave form without potential reversal in voltage gradient appears in the area where the interference exists. However, this area may be not identified using existing methods. The objective of this study was to determine the effect of analyzing direction on the reliability of coating flaw detection of pipes buried in soil using a multi-electrode detector. DCVG on the buried pipe was measured along the buried pipe. This measurement parallel to the pipe was repeated. Measured data were analyzed for parallel, vertical, and diagonal directions. The reliability of coating flaw detection was improved by up to 46.4% compared to the conventional method.

• Korean Chemical Engineering Research
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• 제51권1호
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• pp.73-79
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• 2013

Polycarbonate diol (PCD), isophorone diisocyanate (IPDI)와 dimethylol propionic acid (DMPA)를 출발물질로 하여 수분산 폴리우레탄(waterborne polyurethane dispersion, WPUD)을 합성하였다. WPUD에 아크릴 단량체인 methyl methacrylate (MMA)를 첨가하여 수분산 아크릴 폴리우레탄(waterborne acrylic polyurethane dispersion, AUD)을 합성하였다. 이 AUD와 물에 분산되어 있는 multi-walled carbon nanotube (MWCNT)를 혼합하여 전도성 코팅 용액을 제조한 후 polycarbonate 시트 위에 도포하여 코팅 도막을 형성하였다. AUD 중의 MMA의 첨가량이 증가될수록 코팅 도막의 연필경도, 내마모성 및 내약품성은 향상되었으나 전기 전도도는 감소하였다. 반면에 전도성 코팅 용액 중의 MWCNT의 첨가량이 증가될수록 코팅 도막의 연필경도, 내마모성 및 내약품성은 감소되었으나 전기 전도도는 증가하였다.

• Journal of Pharmaceutical Investigation
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• 제35권6호
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• pp.445-451
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• 2005

As a selective ${\alpha}_{1A}-adrenoreceptor$ antagonist, tamsulosin has been used clinically for urinary obstructed patients with benign prostatic hyperplasia. The single and multi-layered pellets containing tamsulosin hydrochloride were prepared in an effort to control the drug release, avoiding dose-dependent side effects of tamsulosin hydrochloride upon oral administration. The drug release from multi-layered pellets was substantially controlled, compared with single layered pellets. The drug release from coated pellets with single or multi layer was affected by the nature of coating agent, the percentage of coating level and the presence of hydrophilic material in coating layer. In conclusion, the controlled release oral delivery system using multi-layered pellet is very useful for tamsulosin hydrochloride, resulting in improvement of patient compliance and therapeutic drug levels for a longer period of time.

• 한국한의학연구원논문집
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• 제13권2호통권20호
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• pp.47-52
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• 2007

In Oriental medicine, the status of tongue is the important indicator to diagnose one's health, because it represents physiological and clinicopathological changes of inner parts of the body. The method of tongue diagnosis is not only convenient but also non-invasive, therefore, tongue diagnosis is one of the most widely used in Oriental medicine. But tongue diagnosis is affected by examination circumstances a lot. It depends on a light source, degrees of an angle, doctor's condition and so on. So it is not easy to make an objective and standardized tongue diagnosis. As part of way to solve this problem, in this study, we tried to design a discriminant function for white and yellow coating with multi-dimensional color vectors. There were 62 subjects involved in this study, among them 48 subjects diagnosed as white-coated tongue and 14 subjects diagnosed as yellow-coated tongue by oriental doctors. And their tongue images were acquired by a well-made Digital Tongue Diagnosis System. From those acquired tongue images, each coating section were extracted by oriental doctors, and then mean values of multi -dimensional color vectors in each coating section were calculated. By statistical analysis, two significant vectors, R in RGB space and H in HSV space, were found that they were able to describe the difference between white coating section and yellow coating section very well. Using these two values, we designed the discriminant function for coating classification and examined how good it works. As a result, the overall accuracy of coating classification was 98.4%. We can expect that the discriminant function for other coatings can be obtained in a similar way. Furthermore, if an automated segmentation algorithm of tongue coating is combined with these discriminant functions, an automated tongue coating diagnosis can be accomplished.