Synthesis and a Photo-Stability Study of Organic Dyes for Electro-Fluidic Display

Electro-fluidic display (EFD) is one of the most promising reflective displays because of its full color and video speed. Colored EFD oil, which normally consists of soluble organic dyes and non-polar solvent, plays a critical role in color, electro-optical behavior, and the reliability of the EFD devices. In this paper, we report our research on two kinds of electro-fluidic dyes based on anthraquinone and azo pyrazolone, including their synthesis, structure characterization, and application properties. Changes of absorbance curves, color coordinates of oils, and photoelectric responses of devices were studied in detail under accelerated irradiation to investigate the photo-stability and reliability properties of synthesized oil materials and devices. Photoelectric responses and photo stability of dyes are highly varied depending on their structures. We found that 1,4-dlialkylamino anthraqinone and mono azo pyrazolone dyes are much more stable than 1,8-dlialkylamino anthraqinone and corresponding bisazo pyrazolone dyes.