Reliability of liquid crystal cell and immiscibility between dual-curable adhesives and liquid crystal

The dual-curable adhesive used to attach thin film transistors (TFTs) to color filters in the construction process of liquid crystal display (LCD) panels requires fast curing by UV irradiation and strong bond strength after thermal-curing. In addition, it is necessary to consider the immiscibility of the dual-curable adhesives with the liquid crystal, because they come directly into contact with the liquid crystal without curing process in the large LCD panel production. In this study, dual-curable adhesives based on partially acrylated epoxy acrylate oligomers were prepared and investigated with nematic liquid crystals using gas chromatography (GC), polarized optical microscopy and the measurement of the transmittance of the liquid crystal.As the concentration of CC bonds was increased, the immiscibility was enhanced due to the fast curing rate of the partially acrylated epoxy acrylate oligomers and reduced visual contamination was observed in the polarized optical microscope images. Moreover, the transmittance of the liquid crystal cells was not changed before and after the dual-curing of the adhesives and was maintained for 100 h.