• Bulletin of the Korean Chemical Society
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• v.35 no.3
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• pp.731-736
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• 2014

An organic junction transistor with a vertical structure based on an active layer of poly(3-hexylthiophene) was fabricated by facile micro-contact printing combined with the Langmuir-Schaefer technique, without conventional e-beam or photo-lithography. Direct printing and subsequent annealing of Au-nanoparticles provided control over the thickness of the Au electrode and hence control of the electrical contact between the Au electrode and the active layer, ohmic or Schottky. The junction showed similar current-voltage characteristics to an NPN-type transistor. Current through the emitter was simply controllable by the base voltage and a high transconductance of ~0.2 mS was obtained. This novel fabrication method can be applied to amplifying or fast switching organic devices.

• Tribology and Lubricants
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• v.26 no.2
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• pp.142-148
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• 2010

The purpose of this study is to find how to be formed the wet film thickness during the low friction coating process for a piston skirt with application to the theory of screen printing. In other words, in this research, it is to derive the general expressions predicting the pressure under a blade and the volume of coating fluid passing through the blade edge. Using these expressions, it is to be approved that the current operation characteristics of a screen printing system to a sample blade coating process for low friction coating on a piston skirt can be quantitatively assessed.

• Journal of the Korean Applied Science and Technology
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• v.14 no.2
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• pp.27-34
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• 1997

Naphthoquinone-1,2-diazide-5-sulfonyl [NDS]derivatives members of Quinone diazide compound that are utilizable as photoresist for printing plate were synthesized, and photoresist were prepared by mixing these derivatives with a matrix resin(PF, CF) at various weight ratios. Photosensitive characteristics of photoresist were studied by Gray scale method, and SEM to analyze if they can be used as photosensitive material in a printing plate. Experimental results showed using IR, UV, NDS derivatives were photoconverted and developer-soluble photoresist were produced. Photoresist in the mixing ratio of 1:4 of NDS[II] and CF resin gave rise to the highest dissolution rate. In addition, photoresist obtained at this condition resulted in the most superior sensitivity.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.2
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• pp.50-53
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• 2008

A design approach using a one-dimensional (1D) lumped model was studied and applied to an industrial inkjet printing head design for micro patterning on printed circuit boards. For an accurate analysis, a three-dimensional piezoelectric-driven actuator model was analyzed and its jetting characteristics were applied to 1Danalysis model. The performance of the 1D lumped model was verified by comparing measured and simulated results. The developed 1D model helped to optimize the design and configuration of the inkjet head and could be implemented in the design of multi-nozzle inkjet printing heads to improve the jetting frequency and minimize crosstalk.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.05a
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• pp.109-110
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• 2006

Nanocrystalline $TiO_2$ electrode were prepared by spray-printing in order to efficiency and improved fill factor. Different compositions of nanocrystalline $TiO_2$ pastes are described, based on $TiO_2$ powder made by ourselves. The produced by spray printing $TiO_2$ films were compare with the produced by squeeze printing $TiO_2$ films and was studied in the light of static I-V characteristics. The produced $TiO_2$ films are extensively characterized by means of spectroscopy(Ramon, XRD) and microscopy(FE-SEM).

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1457-1458
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• 2009

The fundamental parameters controlling ink-jet printing liquids are the viscosity and surface energy. The wetting contact angle determines the spread of a liquid drop on the surface and depends on the relative surface energy. The characteristics of silver ink-jet printing were studied with control of surface energy and head temperature. Polyethylene terephthalate(PET) film and Si-wafer(ptype) were used as substrates and atmospheric plasma was treated to control the surface energy. With silver ink, the hydrophilic surface treatment could reduce the radius of droplets due to the hydrophobic nature of silver ink.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.889-892
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• 2009

We have developed a practical printing technology for the gate electrode of organic thin film transistors(OTFTs) by combining screen-printing with wet-etching process using nano-silver ink as a conducting material. The screen-printed and wet-etched Ag electrode exhibited a minimum line width of ~5 um, the thickness of ~65 nm, and a resistivity of ${\sim}10^{-6}{\Omega}{\cdot}cm$, producing good geometrical and electrical characteristics for gate electrode. The OTFTs with the screen-printed and wet-etched Ag electrode produced the saturation mobility of $0.13cm^2$/Vs and current on/off ratio of $1.79{\times}10^6$, being comparable to those of OTFT with the thermally evaporated Al gate electrode.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.10
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• pp.104-109
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• 2019

Reverse engineering techniques using 3D scanners and 3D printing technologies are being used in various industries. In this paper, the three-dimensional model is designed for automotive hub parts through 3D scanning and reverse engineering, and the design of hub parts is intended to be printed on FDM-style 3D printers to measure and analyze the dimensions of hub parts designed for reverse design and 3D printed hub parts. Experimental result have shown that the dimensions of 3D printed hub parts are small compared to those of the reverse-engineered dimensions, which are due to the shrinkage of filament materials in 3D printing.

• The Journal of the Korea Contents Association
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• v.15 no.2
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• pp.177-186
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• 2015

This study aims to suggest the direction in which furniture design can contribute, keeping with the trend of small quantity batch production by analyzing cases of furniture design manufacturing. This study analyzed cases of furnitures and lights made by 3D printing with 3 classifications. They are 1st, classification by correlation between 3D printing method and materials, 2nd, classification by 8 formative characteristics of 3D printing furniture design, 3rd, comparison analysis of competitiveness between existing furniture design and 3D printing furniture design by practicality, usability and durability. The competitiveness 3D printing technique arouses in furniture design industry, which is investigated in this thesis, is as follows. 1st, small quantity batch production, which caters to personal taste, is made possible. 2nd, transmission and transportation via digital are became more convenient. 3rd, it brings about a breakthrough in furniture design manufacturing. 4th, there is room for development into the 'smart furniture design' industry through collaborative use of 3D printing and internet of things. 5th, an Eco-friendly method of furniture design is consistently facilitated.

• Clean Technology
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• v.9 no.3
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• pp.107-113
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• 2003

Printing process generates a vast amount of toxical waste and wastewater by the development of printing and publishing industry. The regulations for various environmental pollution material, which were indispensably used in printing industries, were getting stronger. The printing industries should develop the cleaner technologies in order to avoid the regulations. In this paper, the separation characteristics of microfiltration, ultrafiltration, reverse osmosis were surveyed to make basic data for the optimization of process as cleaner technologies for printing industries. The $2kg/cm^2$ of operation pressure were suitable to the U/F System. Because of the permeate of U/F was below 3 NTU as turbidity, which was probed to be possible using the rinsing water in printing process. U/F System,