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http://dx.doi.org/10.4313/TEEM.2003.4.1.021

Washing Effects on Generation of Pretilt Angle in NLC, 5CB, on a Polyimide Surface with Trifluoromethyl Moieties  

Lee, Sang-Keuk (Department of Electrical Engineering, College of Engineering, Kwangwoon University)
Han, Jeong-Min (Department of Electrical and Electronic Engineering(A-226), College of Engineering)
Hwang, Jeoung-Yeon (Department of Electrical and Electronic Engineering(A-226), College of Engineering)
Seo, Dae-Shik (Department of Electrical and Electronic Engineering(A-226), College of Engineering)
Publication Information
Transactions on Electrical and Electronic Materials / v.4, no.1, 2003 , pp. 21-23 More about this Journal
Abstract
The washing effects on pretilt angle generation in a nematic liquid crystal (NLC), 4-n-pentyl-4'-cyanobiphenyl (5CB) on a rubbed polyimide (PI) surface with trifluoromethyl moiety have been successfully studied. The pretilt angle of 5CB is increased by the washing process on the rubbed PI surface. The surface tension on the rubbed PI surface increases with the rubbing strength RS and then saturated above RS: 150 mm. The pretilt angle of 5CB for all washing processes on the rubbed PI surface decreases with the surface tension. We have found that the pretilt angle of 5CB on the rubbed PI surface may be attributed van der walls (VDW) dispersion interaction between the LC molecules and the polymer surfaces having trifluoromethyl moieties.
Keywords
washing effect; pretilt angle; nematic liquid crystal; van der waals(VDW);
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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