• Korea-Australia Rheology Journal
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• v.21 no.2
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• pp.83-89
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• 2009

Coating process plays an important role in information technology such as display, battery, chip manufacturing and so on. However, due to complexity of coating material and fast deformation of the coating flow, the process is hard to control and it is difficult to maintain the desired quality of the products. Moreover, it is hard to measure the coating process because of severe processing conditions such as high drying temperature, high deformation coating flow, and sensitivity to the processing variables etc. In this article, the coating process is to be re-illuminated from the rheological perspectives. The practical approach to analyze and quantify the coating process is discussed with respect to coating materials, coating flow and drying process. The ideas on the rheology control of coating materials, pressure and wet thickness control in patch coating process, and stress measurement during drying process will be discussed.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.348-348
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• 2009

The conductive coating method is used for various industrial fields. For example, Sputtering process is used to coat ITO layer in LCD or OLED panel manufacture process and fabricate a base layer of substrate of an electric printing device. However, conventional coating processes (beam sputtering, spin coating etc.) has a problems in the industrial manufacturing process. These processes have a very high cost and critical manufacturing environment as a vacuum process. Recently, many researchers have proposed various printing process instead of conventional coating processes. In this paper, we propose an ESD printing process in ITO coating layer and apply to fabricate a conductive coating film. Furthermore, the effect of the nozzle and also the applied voltage on different configuration of the nozzle head was also studied for better understanding of the Electro Static deposition process.

• Corrosion Science and Technology
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• v.8 no.4
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• pp.157-161
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• 2009

The corrosion resistance of reinforcing bar was studied to endure the marine environment during shipment. The red rust on the surface did not damage the adherence in the concrete structures, especially in highly alkaline environment, but made the consumer doubt of the quality. The passivation process by alkalization of the quenching water in the tempcore process failed to endure the long shipping period. The ceramic coating by sol-gel process improved the corrosion resistance without damaging the mechanical properties and adherence between concrete and reinfiorcing bar. Optimal concentration of the coating solution and coating temperature were tested. No additional energy was necessary for the coating process by spraying during cooling process, resulting simplified process and low cost. Salt spray test, cyclic corrosion test and atmospheric test were employed to confirm the resistance. The corrosion rates were presented by rating number and polarization resistance. The coating layer was examined by FIB, XRD and SEM etc.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.10
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• pp.1144-1148
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• 2012

Process conditions for generating nano patterns handle different process according to the pattern characteristics, and different process data according to patterns in questions. To efficiently find optimal process conditions for generating nano patterns, process data by experiment is needed consideration of the pattern characteristics concerning the equipment. In particular, coating methods of a cylindrical mold differ from it of a flat plate because of viscosity of coating materials. Also the coating thickness affects nano process and pattern line width. So coating method of coating thickness for cylindrical mold is very important on nano pattern generating. In this study, a method is proposed for coating Photo Resist through the spray in order to coat cylindrical mold and measuring the thickness of coating using measuring tip considering the size of cylindrical mold because there is no method in the existing SEM. The proposed method is applied to a real printed electronics system to verify its accuracy and efficiency.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.2
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• pp.159-166
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• 2015

Slot-die coating is well known technique to guarantee a uniformly coated layer and is compatible with roll-to-roll process. In actual roll-to-roll slot-die coating process, the lateral difference of coated layer thickness is observed. An experimental study was performed to improve the coating quality. Coating speed and coating gap were selected as the experimental factors. A full factorial, statistical method was conducted to optimize the process conditions. Based on the results of repeated experiment, the lowest deviation of lateral thickness (700 nm, <10%) was achieved at 10 m/min coating speed and $300{\mu}m$ coating gap. This result has significance because such optimized process guideline can be utilized with all process improvement in various coating applications.

• Journal of the Semiconductor & Display Technology
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• v.17 no.4
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• pp.80-85
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• 2018

The present investigation on optical fiber mass manufacturing features the computational modeling and simulation on a double layer liquid coating process on glass fiber surface. The computational model employs a simplified geometry of typical fiber coating system which consists of primary and secondary coating dies along with secondary coating cup. The viscous dissipation in coating flow is incorporated into the double layer coating process simulations. Heavy temperature dependence of coating liquid viscosity is also considered in the model. The computational results found that the effects of viscous dissipation on both primary and secondary coating layer thicknesses are highly significant at higher drawing speed. Several important coating process parameters such as supply temperature and pressure of primary and secondary coating liquids are investigated and discussed in order to appreciate how those parameters affect the double layer coating layer thickness on fast moving glass fiber.

• Journal of the Korean Applied Science and Technology
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• v.22 no.3
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• pp.234-240
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• 2005

In this study, we have prepared three kinds of enteric tablet coating formulations for prevention the crack incidence and enhanced process improvement of enteric tablet using aqueous system. we determined the mechanical strength of three formulatons on the enteric film-coating process. The compared experiment of one-layer and two-layer (A), (B) coating treated having placebo tablets without breakline and logo. In result, the breaking force time of two-layer (B) film strength was found to increase 0.8min than two-layer (A). We confirmed the half reduction of working hour and the simplification in the one-layer coating process, and the coating troubles was solved as setting up a dehumidifier in inlet of coater. In result, we recovered that optimum running capacity(g/kg) of dehumidifier is 10g/kg and below.

• Tribology and Lubricants
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• v.25 no.6
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• pp.414-420
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• 2009

In this study, using the general expressions predicting the pressure under a blade and the volume of coating fluid passing through the blade edge, it is predicted the change of the coating wet film thickness related with various parameters determining the characteristics of this blade coating process. Using the results of this research, it can be found the optimized coating wet film thickness taking into account the parameters related with various coating process on various metal surfaces will be able to be predicted.

• Journal of ILASS-Korea
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• v.13 no.4
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• pp.193-199
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• 2008

Spray coating is a versatile surface modification technology in which coating is built-up based on the successive deposition of micron-scaled particles. Depending on the coating materials, the coatings can meet the required mechanical properties, corrosion resistance, and other properties of base materials. Spraying processes are mainly classified into thermal and kinetic spraying according to their bonding mechanism and deposition characteristics. Specifically, thermal spraying process can be further classified into many categories based on the design and mechanism of the process, such as frame spraying, arc spraying, atmospheric plasma spraying (APS), and high velocity oxygen-fuel (HVOF) spraying, etc. Kinetic spraying or cold gas dynamic spraying is a newly emerging coating technique which is low-temperature and high-pressure coating process. In this paper, overall view of thermal and kinetic spray coating technologies is discussed in terms of fundamentals and industrial applications. The technological characteristics and bonding mechanism of each process are introduced. Deposition behavior and properties of technologically remarkable materials are reviewed. Furthermore, industrial applications of spray coating technology and its potentials are prospected.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.57-60
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• 2009

The conductive coating method was used for a various industrial fields. For example, Sputtering process is using to a coat of ITO layer in LCD or OLED panel manufacture process and fabricate a base layer of substrate of an electric printing device. However, conventional coating process (beam sputtering, spin coating etc.) has a problems in the industrial manufacturing process. These processes have a very high cost and critical manufacturing environment as a vacuum process. Recently, many researchers were proposed a various printing process instead of conventional coating process. In this paper, we propose an ESD printing process in ITO coating layer and apply to fabricate a conductive coating film. Ours transparent electrode had a surface resistance of about $66{\Omega}/{\square}$ and transparent of 74% in the wavelength of 500nm. This transparent electrode manufacturing process will be applied to Roll-to-Roll process. In addition, we developed roll printing process system for the next generation flexible solar cell.