This paper introduces a novel alignment method for control of pretilt angles in liquid crystals (LCs) using an etchant dipping effect on a mixed polyimide layer as an alternative alignment layer for liquid crystal display applications. A rubbing process was used to induce LC alignment and induce the measured LC pretilt angle on the etchant dipped mixture layer. The resulting thermal stabilities were good, however thermal stresses decreased as the etchant dipping time increased, indicating that the LC anchoring energy became weaker as a function of etchant dipping time after treatment. Excellent voltage-transmittance characteristics for vertically aligned cells were observed for all conditions.
Bibliographical noteFunding Information:
The authors would like to thank the Petroleum, Oil and Gas Corporation of South Africa (PetroSA) for their financial support and technical discussions, the National Research Foundation (NRF) for granting Ebrahim Mohiuddin a scholarship, Makana Brick for supplying the raw kaolin, the electron microscope unit, Physics department, University of the Western Cape for the SEM images, Mrs E. Antunes, Chemistry department, University of the Western Cape and Dr. D.J. Brand, University of Stellenbosch for the solid state NMR work and Ithemba labs for the XRD work.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics