Set forth is a method of forming an electrophoretic display device that
includes locating a multiplicity of individual reservoirs containing a
display fluid between conductive substrates, at least one of which is
transparent, to form a device, wherein the display fluid comprises at
least two sets of particles in a liquid medium, the at least two sets of
particles exhibiting a different color, and charging each of the sets of
particles to have a different charge via application of an electric field
to the device. This field induced charging of the sets of differently
colored particles enables low conductivity particles with superior
electrophoretic mobility to be achieved.