A novel method for producing charged particles suspended in a dielectric fluid for electrophoretic display is presented. Typical charged particles for electrophoretic display contain polymer resin, color pigment, and/or charge controlling compound. Many methods for producing charged particles have been reported including the polymerization in the presence of pigment particles. In this paper, we described a method to meltmix polymer resin, pigment, and charge controlling agent all together in the dielectric fluid such as Isopar. The resulting solution contains charged color particles with average particle size about 2 μm or less. The colored particle solution was mixed with white particle solution containing titanium dioxide to form a two-color switching electrophoretic display. The display built with such two-particle solution was demonstrated. The solutions of two-color particles can be sealed between two thin plastic films with small divided compartments. A roll-to-roll manufacturing method that provides large area of small compartment with two-color particle solutions was discussed.
Pinyen Lin, Chieh-Min Cheng, David H. Pan, "Novel Liquid Toner Electrophoretic Display" in Proc. IS&T Int'l Conf. on Digital Printing Technologies and Digital Fabrication (NIP25), 2009, pp 449 - 451, https://doi.org/10.2352/ISSN.2169-4451.2009.25.1.art00014_2