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Bae, Sung Woo;Kwak, Sun Woo;Kim, In Young;Noh, Yong-Young
- Journal of the Korean Society for Precision Engineering
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- v.30 no.6
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- pp.578-583
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- 2013
The lighting devices using organic light emitting diodes (OLEDs) are actively researched because of the various advantages such as high power efficiency and 2-dimensitonal lighting emitting. To commercialize those OLED lighting devices, the manufacturing cost must be downed to comparable price with conventional light sources. Here, we demonstrate a reverse gravure-offset or gravure off-set printed metal electrode for the auxiliary electrode for OLED lighting devices. For the fabricated OLED's auxiliary electrode, we used Ag nano-paste and printed metal grid structure with a line width and spacing of several ten and hundred micrometer by using gravure-offset printing. In the end the printing metal grid pattern are successfully achieved by optimization of various experimental conditions such as printing pressure, printing speed and printing delay time.
https://doi.org/10.7736/KSPE.2013.30.6.578 인용 PDF KSCI

Noh, Jae-Ho;Lee, Taik-Min;Park, Sang-Ho;Jo, Jeong-Dai;Kim, Dong-Soo
- Journal of the Korean Society for Precision Engineering
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- v.27 no.9
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- pp.16-19
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- 2010
This paper presents how to design and fabricate the gravure offset printing system for enhancement of register precision. Factors of precision error are caused by imprecision of gravure plate, deformation of substrate, printing quality change due to the change of ink viscosity, Imprecision of printing machine, and so on. This study suggests concept design of gravure offset printing system which is able to minimize or remove these error factors.
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Kang, Hyun-Wook;Huang, Wei-Xi;Sung, Hyung-Jin;Lee, Taik-Min;Kim, Dong-Soo
- Proceedings of the KSME Conference
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- 2008.11a
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- pp.1098-1102
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- 2008
To increase the ink transfer rate in the micro-gravure-offset printing, the liquid transfer process between two separating plates is investigated. During the liquid transfer process, in which one plate is fixed and the other one moves vertically, a sessile droplet is separated into two droplets. The volume ratio of the two droplets depends on the contact angles of the two plates. In a numerical study of the ink transfer processes, liquid transfer between two parallel separating plates and between a trapezoidal cavity and an upward moving plate are simulated, as models of the printing of ink from the offset pad onto the substrate and the picking up of ink from the gravure plate by the offset pad, respectively. Also, in experimental study, to obtain various surface contact angles, chemical treatment, plasma treatment, and electrowetting- on-dielectric (EWOD) surface are considered. The transfer rate between two plates is calculated by analyzing the droplet images. From the results, the optimal surface contact angles of the units of the micro-gravure-offset printing can be characterized.
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Kim, Chung-Hwan;Choi, Byung-Oh;Ryu, Byung-Soon;Lim, Kyu-Jin;Lee, Myung-Hoon;Kim, Dong-Soo
- Proceedings of the KSME Conference
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- 2007.05a
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- pp.461-466
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- 2007
There has been a great interest in printing technology as a low cost and mass production method for the application of printed electronics such as printed TFT, solar cell, RFID Tag, printed battery, and so on. In this study, apparatuses of gravure-offset printing are developed for fine line-width/gap printing and examining pattern distortion occurred in gravure-offset printing process. The fine line-width/gap pattern shows that it is possible to make around 20 micro-meter line-width/gap printing patterns. Pattern distortion is modeled, and the amount and shape of the distortion are calculated by using commercial FEM code. The roll-to-roll printing system under development consists of unwinder/rewinder, two printing units, one coating unit, drying units, guiding unit, vision system, and other auxiliary devices. For multi-layer printing, the system is designed to be capable of printing two different materials.
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