Surface Processing of Polyethylene Terephthalate for Orientation of Nematics in Display Devices

Abstract

Thermoplastic polymers have found widespread applicability in electronic industry owing to their facile processing and relatively low costs. Transparent polymer foils, like polyethylene terephthalate (PET), can be utilized in manufacturing components for liquid crystal display (LCD) devices. This work is focused on surface processing of PET through different procedures. The induced surface modifications of polymer samples were analyzed by optical microscopy. Contact angles of nematic drops on PET film are measured to evaluate how the method of surface modification reveals that the surface texturing affects the interactions of polymer with the liquid crystal. The influence of created surface anisotropy on the work of adhesion at polymer/liquid crystal interface is analyzed. Preliminary assessment of nematic orientation on the surface of modified PET foils is performed using polarized light. The results were discussed in regard with the used methodology to adapt the surface of the PET films to achieve optimal orientation of nematic molecules. The obtained data will open new perspectives on processing polymer foils as alignment layers used in LCD devices.