Copytele, Inc.

Coulter Corporation

Wei-Hsin Hou

Frederic E Schubert

Thomas B Lloyd

Denis A Krusos

Frank J DiSanto

Jing Hong Chen

George Semertzidis

A color electrophoretic display including a plurality of cells each containing electrophoretic particles. Each of the cells in the plurality is capable of displaying at least one of three selected primary colors, when the particles in the cell are moved from a first rest position to a second display position on the cell. An electrode is coupled to each of the cells and is operative when biased to move the particles from the first rest position to the second display position thereby displaying primary colors in the second display position and causing the display to provide full color capability according to particle position in the cells.

Multi-color electrophoretic image display

A process for forming dielectric particles includes admixing a first monomer and a crosslinker in a liquid dispersion medium to form a first mixture. A second mixture of an initiator and a stabilizer is prepared and added to the first mixture to form a third mixture in which the first monomer polymerizes to form polymer particles. A second monomer is introduced to the third mixture, the second monomer at least partially polymerizing and grafting upon the previously formed polymer particles. A functional monomer effecting the outer surface charge characteristics of the final particles may be introduced to the third mixture when the second monomer is introduced. The particles may be employed in an electrophoretic fluid for use in an electrophoretic display by dispersing the dielectric particles prepared by the two stage polymerization process in a dielectric fluid.

Black and white electrophoretic particles and method of manufacture

A dielectric dispersion for use in an electrophoretic display includes a dielectric fluid, a first plurality of particles of a first color having a surface charge of a selected polarity dispersed within the dielectric fluid and a second plurality of particles of a second color having a surface charge of opposite polarity to that of the first plurality and a steric repulsion thereto preventing coagulation of the first and second pluralities. In one embodiment, the first and second plurality of particles are each formed by separate two stage dispersion polymerization reactions. Each set of particles is formed with unique secondary and functional monomers. Corresponding charge control agents are added to the dispersion to establish opposite polarities on the respective particles.

Methods of preparing electrophoretic dispersions containing two types of

The present invention are dielectric black particles for use in electrophoretic images displays, electrostatic toner or the like, and the corresponding method of manufacturing the same. The present invention black particles are latex particles formed by a polymerization technique, wherein the latex particles are stained to a high degree of blackness with a metal oxide.

Black electrophoretic particles and method of manufacture

Properly-coated pigment particles for use in an electrophoretic display include pigment particles having a pre-determined density and application of a polymeric coating to the pigment particles, wherein the coating comprises a near fluoropolymer, and wherein the density of the fluoropolymer is substantially the same as the density of the pigment particles. When a polymeric coating is applied having a density that is substantially the same as the density of the pigment particles, even though the particles comprise a distribution of particle sizes, the density of the pigment particles is not significantly altered. In a preferred embodiment, the pigment particle comprises a diarylide yellow pigment, having a density of 1.43 g/ml, coated with a polymer made from the monomer 2,3,4,5,6-Pentafluorostyrene, having a density of 1.41 g/ml.

Polymeric-coated dielectric particles and formulation and method for

A process for forming dielectric particles includes admixing a vinyl halide monomer and a crosslinker in a liquid dispersion medium to form a first mixture. A second mixture of an initiator and a stabilizer is prepared and added to the first mixture to form a third mixture in which the monomer polymerizes to form white crystalline polymer particles which are sonified for uniformity. The particles may be stained by exposure to a dehydrohalegenation reagent and dispersed in an electrophoretic fluid for use in an electrophoretic display.

Colored polymeric dielectric particles and method of manufacture

A dielectric suspension for use in an electrophoretic image display, electrostatic printing or the like, comprising a suspension medium including a dense fluorinated solvent and a less dense hydrocarbon solvent, a plurality of pigment particles dispersed in the suspension medium, a fluid dye dissolved in the suspension medium for providing a contrast with the pigment particles, and a charge control agent adsorbed on the pigment particles for preventing the pigment particles from agglomerating.

Planar fluorinated dielectric suspensions for electrophoretic image

A method of making liquid toner for electrophotographic imaging by forming a mixture of a polyamide polymer, a good solvent therefor and a particulate pigment, heating the polymer/pigment/solvent mixture to form a solution thereof, cooling the resulting solution to precipitate fine polymer-encapsulated pigment particles of generally uniform size and morphology, removing the precipitated particles, removing the solvent and redispersing the resulting particles in dispersant medium along with a charge-control agent to form the liquid toner. A steric stabilizer can be added to the polymer-encapsulated pigment particle dispersion.

Method of making a liquid toner for electrophotographic imaging

Black electrophoretic particles for an electrophoretic image display

A polyamide polymer and one of methanol, ethanol and 2-propanol are formed into a solution by heating at 70 degrees Celsius for approximately two hours, the resulting solution is cooled to precipitate the polymer as particles from said solution. Alternatively, a non-solvent to said polymer may be added to effect precipitation of said polymer particles. The solvent is removed and the particles isolated and dried to form a dry powder. Fine particulate material such as a pigment, may be included with the polymer and solvent in formation of the solution. The resulting solution may be cooled at a rapid rate to precipitate the particles as polymer-encapsulated pigment particles of generally uniform size and morphology, the surface characteristics such as surface area being controlled. The precipitated polymer particles may be classified when dispersed in a dispersant medium, as mono-dispersed particles. The polymer-encapsulated pigment particles are isolated, dried and may be redispersed in a dispersant medium along with a charge control agent and a steric stabilizer to form a liquid toner for electrophotographic imaging. Alternatively, the solvent can be removed by washing with a non-solvent, the charge control agent added with the dispersant to form the liquid toner. Particles other than pigment may be polymer-encapsulated using the precipitation method disclosed. The non-solvent may be any solvent which has a poor thermodynamic quality for the polymer.

Method of forming fine polymer particles and polymer-encapsulated

A method for forming fine polymer particles, including core/shell polymer composite particles and polymer-encapsulated liposome particles. A polymer solution is formed using a selective solvent which enables the polymer to be precipitated from the solution upon a change in condition thereof. The change in condition may be effected by lowering of the temperature of the solution and/or introducing a non-solvent to the solution. With respect to the formation of the polymer-encapsulated liposome particles, the liposome particles are included when the polymer solution is formed. One embodiment of the method for forming the core/shell particles includes the selective solvent being immiscible with water to form the polymer solution (oil phase), the addition of deionized water containing an emulsifier to the solution, forming the emulsion, cooling the resulting emulsion to precipitate a one polymer from the emulsion as oil drops leaving the other polymer in solution therein, evaporating the selective solvent solidifying the other polymer thereby encapsulating the one polymer forming the core/shell particles.

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Bethlehem, PA, United States of America

Wei-Hsin Hou