Patent ID: 7525719
Filing Date: 2009-04-28
Classification: G02B,G02F

Abstract:
1. Particles for displaying images used in an image display device which displays images by flying and moving at least one group of particles enclosed between a pair of facing substrates of which at least one is transparent and across the substrates, an electric field being applied, wherein the ingredients for the particles satisfy at least one requirement among the following: (1) Span of ingredient particle diameter distribution defined by the following equation is less than 5: wherein d0.1 represents an ingredient particle diameter (μm) of the ingredient particles whose ratio of ingredient particles equal to or less than d0.1 is 10%, d0.5 represents an ingredient particle diameter (μm) defining that 50% of the ingredient particles are greater than d0.5, and another 50% of the ingredient particles are smaller than d0.5, d0.9 represents an ingredient particle diameter of the ingredient particles whose ratio of ingredient particles equal to or smaller than d0.9 is 90% each in the ingredient particle diameter distribution; (2) in the case where the surfaces of the ingredient particles are charged by applying a voltage of 8 kV onto a Corona generator deployed at a distance of 1 mm from the surface of the ingredient particles, a surface potential of the ingredient particle 0.3 second after the discharge is greater than 300 V; (3) a ratio between a surface hardness at 0° C. and a surface hardness at 100° C. is 1.7 or smaller; (4) tensile break strength is 20 MPa or greater; (5) Izod impact strength (with a notch) is 100 J/m or greater; (6) abrasion loss (Taber) is 22 mg or less; (7) tensile elastic modulus is 24.5 MPa or greater; (8) flexural elastic modulus is 44.1 MPa or greater; (9) tear strength is 100 kg/cm or greater; and (10) ingredient particles involve indefinite particles around which at least one resin layer is formed by coating a resin comprising a component whose index of refraction is different from that of the indefinite particles, wherein the solvent-indissoluble ratio of the ingredient particles in a solvent defined by the following equation is 50% or greater: wherein A represents the weight of said ingredient particles before they are immersed into the solvent, and B represents the weight of said ingredient particles after immersing them in a non-defective solvent for 24 hours at the temperature of 25° C.