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http://dx.doi.org/10.7317/pk.2012.36.2.145

Effects of UV Irradiation and Thermal Treatment of Photo-Degradable Polyimide Layer on LC Alignment  

Lee, Jang-Ju (Department of Chemical Engineering, Kyung Hee University)
Lee, Won-Ho (Department of Chemical Engineering, Kyung Hee University)
Shin, Yong-Il (Department of Chemical Engineering, Kyung Hee University)
Paek, Sang-Hyon (Department of Chemical Engineering, Kyung Hee University)
Publication Information
Polymer(Korea) / v.36, no.2, 2012 , pp. 145-148 More about this Journal
Abstract
The effects of the linearly polarized UV (LPUV) irradiation and thermal treatment of a photo-degradable polyimide (CBDA-ODA) alignment layer (AL) on its AL properties, liquid crystal (LC) alignment, and LCD characteristics have been investigated. The best quality of LC photo-alignment have been induced by the LPUV-irradiation with much (about 5~10 times) less dosage than that generating the maximum anisotropy of the AL. A thermal treatment of the LPUV-irradiated AL has effectively removed the undesirable, low-M.W. fragments of the AL generated during the photo-decomposition and increased the stability of the AL, which has resulted in improvement of the LC alignment and the LCD property.
Keywords
linear polarized UV irradiation; polyimide; photo-degradation; liquid crystal alignment; thermal treatment;
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  • Reference
1 T. Uchida, M. Hirano, and H. Sakai, Liquid Crystals, 5, 1127 (1989).   DOI
2 W. S. Dong, M. H. Lee, and S. H. Paek, Polymer(Korea), 27, 484 (2003).
3 K. Sakamoto, K. Usami, and S. Ushioda, J. Appl. Phys., 93(2), 1039 (2003).   DOI   ScienceOn
4 K. R. Ha and J. L. West, J. Appl. Polym. Sci., 86, 3072 (2002).   DOI   ScienceOn
5 M. Hasegawa and Y. Taira, J. Photopoly. Sci. Technol., 8, 241, (1995).   DOI   ScienceOn
6 K. Sakamoto, K. Usami, and S. Ushioda, J. Appl. Phys., 33, 1435 (1999).
7 M. O'Neill and S. M. Kelly, J. Phys. D: Appl. Phys., 33, 67 (2000).   DOI   ScienceOn
8 V. Chigrinow, V. Kozenkov, and H. S. Kwok, Photoalignment of Liquid Crystalline Materials: Physics and Application, Wiley-SID series, 2008.
9 J. J. Lee, E. J. Kim, and S. H. Paek, Mol. Cryst. Liq. Cryst., 539, 196 (2011).
10 N. Kaqatsuki and Y. Koezuka, Polymer, 50, 2349 (2009).   DOI   ScienceOn
11 K. Takatoh, M. Hasegawa, M. Koden, N. Itoh, R. Hasegawa, and M. Skamoto, Alingment Technologies and Applications of Liquid Crystal Devices, Taylor & Francis, London and New York, 2005.