Inkjet-printed patterned polytitanosiloxane-fluoropolymer composite dielectric layer for micro-optical electrowetting valves

Abstract Fluid motion control has always been essential in electrowetting devices. Using the inkjet printing technique, an organic-inorganic hybrid material, polytitanosiloxane, was patterned as a secondary dielectric under the hydrophobic fluoropolymer coating in an optical electrowetting device (OEWD). The effects of different structural parameters of the inkjet-printed polytitanosiloxane (IPP) layer on both the fluid motion at the microscopic level and the macroscopic visual performances of the device were studied experimentally. The leakage-current test was also performed to evaluate the insulating performance of the composite dielectric layer. In addition, COMSOL Multiphysics was used to simulate the fluid flow inside the OEWD with/without the polytitanosiloxane layer. The results showed that, by introducing this IPP layer, precise fluid motion control and improved performance could be obtained.