Preparation and Orthogonal Analysis for Dual-Responsive Electrochromic Polymer Dispersed Liquid Crystal Devices

In this work, we provide a fabrication method for dual-responsive electrochromic (EC) polymer dispersed liquid crystal (PDLC) devices. The EC PDLC device was developed by combing the PDLC technique and a colored complex formed via a redox reaction without a specific EC molecule in a simple preparation method. The mesogen played dual roles in the device for scattering in the form of microdroplets and participating in the redox reactions. Orthogonal experiments were performed with the acrylate monomer concentration, the ionic salt concentration, and the cell thickness as factors to investigate the electro-optical performance for the achievement of optimized fabrication conditions. The optimized device presented four switchable states modulated by external electric fields. The light transmittance of the device was changed by an alternative current (AC) electric field while the color change was realized by a direct current (DC) electric field. Variations of mesogen and ionic salt species can modulate the color and hue of devices, which solves the disadvantage of a single color for traditional EC devices. This work lays the foundation for realizing patterned multi-colored patterned displays and anti-counterfeiting via screen printing and inkjet printing techniques.

Automated summary

In this study, a fabrication method for dual-responsive electrochromic (EC) polymer dispersed liquid crystal (PDLC) devices was developed. By combining the PDLC technique and a colored complex formed via a redox reaction, an EC PDLC device was prepared using a simple method. The mesogen in the device played dual roles in scattering and participating in redox reactions. Orthogonal experiments were conducted to investigate the electro-optical performance under different factors, resulting in an optimized device with four switchable states modulated by external electric fields. The color and hue of the device can be modulated by variations of mesogen and ionic salt species, solving the limitation of single color in traditional EC devices. This work lays the foundation for patterned multi-colored displays and anti-counterfeiting using screen printing and inkjet printing techniques.