Novel Color Electrophoretic Imaging Display Based on Movement of Particles Using Two Driving Electrodes

We are studying a color electrophoretic imaging display. This display has an electrophoretic liquid, which contains nonelectrophoretic particles, positively and negatively charged electrophoretic particles. We fabricated five kinds of white, black and magenta electrophoretic particles using chemical polymerization technique, and developed two types of electrophoretic dispersion liquid. One type contains positively charged electrophoretic magenta particles, negatively charged electrophoretic black particles, and non-electrophoretic white particles. The other type contains negatively charged electrophoretic magenta particles, positively charged electrophoretic black particles, and non-electrophoretic white particles. This display has three colored states, which are controlled by two driving electrodes. The two driving electrodes and a common transparent electrode were set on the back and front glass plate in this display cell, respectively. For the first state, the two driving electrodes were set at positive voltage so that negatively charged electrophoretic particles appeared at the visual surface. For the second state, the two driving electrodes were set at negative voltage so that positively charged electrophoretic particles appeared at the visual surface. For the third state, the two driving electrodes were set at opposite voltages to each other so that non-electrophoretic white particles appeared at the visual surface.