Disclosed is a method of preparing encapsulated bichromal balls. The method involves forming capsules of electrophoretic particles encapsulated within a dielectric fluid such as a hydrocarbon solvent or siloxane oil that includes a small amount of a gelating agent. Bichromal balls are then formed by heating the capsules and applying an electric field. The capsules are then cooled while the electric field is maintained. Upon sufficient gelling, the electrophoretic particles are fixed within the gelled medium, i.e. the capsule. The bichromal gel produced detaches from the inside wall of the capsule, and thereby constitute the resulting encapsulated bichromal balls.

 
Web www.patentalert.com

> Optical filter and optical device

~ 00300