Synthesis and application of an alkylated pyrazole‐based azo dye for electrofluidic display

Abstract Electrofluidic display (EFD) is one of the most promising reflective displays for its full color and video speed. Colored EFD oil, normally formulated by soluble organic dyes in non‐polar solvent, dominates the color, electro‐optical behavior, and reliability performances for EFD devices. In this paper, a novel yellow electrofluidic dye with excellent solubility in non‐polar EFD solvent was achieved based on the introduction of long alkyl chain into pyrazole azo dye. The resulting EFD device fabricated by the dye showed excellent application properties, such as fast switching speed (17.8 ms), high aperture ratio (68.5%), low threshold voltage (24v), good light stability (240 h under accelerated conditions), and low backflow phenomenon.