Working fluids for electrophoretic image display devices
AssigneePlessey Handel und Investments AG
InventorsChristopher Frederick Carter, Roy Trevor Blunt, James Cyril Alexander Lewis, Geoffrey Michael Garner
Life of this patent
Estimating the term…
Abstract
The invention provides a working fluid for an electrophoretic image display device including a dispersion of a species of finely divided particles of an opaque dielectric material suspended in a suspension medium, each of the said particles which are transportable within the suspension medium under the influence of an electric field, has a chemical compound adsorbed on the surface thereof, the chemical compound is such that the molecules thereof exert an attractive force towards each other in the absence of the electric field.
Claims16
A working fluid for an electrophoretic image display comprising a dispersion of a species of finely divided particles of an opaque dielectric material suspended in a suspension medium, each of said particles having a chemical compound adsorbed onto the surface thereof and forming a coating thereon such that repulsive forces between the particles are modified by short range attractive interactions of functional groups possessed by the chemical compound, and wherein said coated particles undergo selected transportation in dependence upon an applied electric field having a potential equal to or greater than the voltage threshold created by the dipole interaction between said coated particles.
An electrophoretic image display device including a working fluid, said working fluid comprising a dispersion of a species of finely divided particles of an opaque dielectric material suspended in a suspension medium, wherein each particle has a chemical compound adsorbed onto the surface thereof and forming a coating therein such that repulsive forces between the particles are modified by short range attractive interactions of functional groups possessed by the chemical compound, and wherein said coated particles undergo selective transportation in dependence upon an applied electric field having a potential equal to or greater than the voltage threshold created by the dipole interaction between said coated particles.
An electrophoretic image display device comprising an array of individual addressable image display elements, said array including a working fluid comprising a dispersion of a species of finely divided particles of an opaque dielectric material suspended in a suspension medium, wherein each particle has a chemical compound adsorbed onto the surface thereof and forming a coating thereon such that repulsive forces between the particles are modified by short range attractive interactions of functional groups possessed by the chemical compound, and wherein the coated particles undergo selective transportation in dependence upon an applied electric field having a potential equal to or greater than the voltage threshold created by the attractive interaction thus generated between said coated particles.
Dependencies are inferred from the claim text.