METHODS FOR ACHIEVING IMPROVED COLOR IN MICROENCAPSULATED ELECTROPHORETIC DEVICES

• US 20100156780A1
• Filed: 10/30/2009
• Published: 06/24/2010
• Est. Priority Date: 07/08/1998
• Status: Abandoned Application

• Current Assignee: E Ink Corporation (E Ink Holdings Incorporated)
• Original Assignee: E Ink Corporation (E Ink Holdings Incorporated)
• Inventors: Drzaic, Paul S., Jacobson, Joseph M., Wilcox, Russell J., Morrison, Ian D.
• Application Number:
  US12/609,149
• Publication Number:
  US 20100156780A1
• Time in Patent Office: Days
• US Class Current: 345/107
• CPC Class Codes: B05D 5/06 to obtain multicolour or other optical effects B05D5/02 takes precedence
• CPC Class Codes: B41J 2/2117 Ejecting white liquids
• CPC Class Codes: B41J 3/4073 Printing on three-dimensional objects not being in sheet or web form, e.g. spherical or cubic objects B41J3/283, B41J3/286 take precedence; building up a 3D object using individual droplets from jetting heads B29C64/112
• CPC Class Codes: B41J 3/4076 printing on rewritable, bistable "electronic paper" by a focused electric or magnetic field
• CPC Class Codes: G02B 26/026 based on the rotation of particles under the influence of an external field, e.g. gyricons, twisting ball displays based on orientable dipolar particles G02F1/172; based on electrophoresis G02F1/167
• CPC Class Codes: G02F 1/133305 Flexible substrates, e.g. plastics, organic film
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 1/16757 Microcapsules
• CPC Class Codes: G02F 2202/28 Adhesive materials or arrangements
• CPC Class Codes: G09F 9/302 characterised by the form or geometrical disposition of the individual elements
• CPC Class Codes: G09F 9/372 the positions of the elements being controlled by the application of an electric field
• CPC Class Codes: H10K 10/462 Insulated gate field-effect transistors [IGFETs]
• CPC Class Codes: H10K 19/00 Integrated devices, or assemblies of multiple devices, comprising at least one organic element specially adapted for rectifying, amplifying, oscillating or switching, covered by group H10K10/00
• CPC Class Codes: H10K 85/30 Coordination compounds
• CPC Class Codes: H10K 85/60 Organic compounds having low molecular weight H10K85/10 - H10K85/50 take precedence

Abstract

A method for manufacturing a full color, reflective display includes the steps of depositing a first plurality of electrophoretic display elements in substantial registration with a first electrode and a second plurality of electrophoretic display elements in substantial registration with a second electrode. The electrophoretic display elements include a capsule containing a species of particles dispersed in a suspending fluid. The selective deposition of the display elements can be achieved by ink jet printing methods, screen printing methods or other printing methods. In some embodiments the electrodes are printed onto the substrate before selective deposition of the display elements, while in other embodiments the substrate is provided having the electrodes already disposed on it. In still other embodiments, the sequence of printing of electrodes and electrophoretic display elements can be varied.

Claims

1. A method of manufacturing a color electrophoretic display comprising the steps of:

(a) providing a first reflective surface comprising a first color;

(b) depositing a first electrophoretic display element in substantial registration with said first reflective surface, said first display element being capable of switching between said first color and a second color when addressed;

(c) providing a second reflective surface comprising a third color; and

(b) depositing a second electrophoretic display element in substantial registration with said second reflective surface, said second display element being capable of switching between said third color and a fourth color when addressed, and at least one of said third and fourth colors is neither said first color nor said second color.

2. A method according to claim 1 further comprising the steps of:

(e) providing a third reflective surface comprising a fifth color; and

(b) depositing a third electrophoretic display element in substantial registration with said third reflective surface, said third display element being capable of switching between said fifth color and a sixth color when addressed, and thereby providing a full color display.

3. A color electrophoretic display comprising:

a display element having a viewing surface and a rear surface on opposed sides of the display element, said display element comprising a plurality of a first species of electrophoretic particles having a first color and a plurality of a second species of electrophoretic particles having a second color different from the first color;

a colored surface disposed adjacent said rear surface of said display element, said colored surface having a third color different from said first and second colors, said display element having a first state in which said plurality of said first species of particles lie adjacent said viewing surface and said first color is displayed, a second state in which said second species of particles lie adjacent said viewing surface and said second color is displayed, and a third state in which said colored surface is visible through said viewing surface and said third color is displayed.

4. The color electrophoretic display of claim 3 wherein one of said first, second and third colors is white and the other two colors are complementary colors.

5. The color electrophoretic display of claim 4 wherein one of said first, second and third colors is white and the other two colors are red and cyan.

6. The color electrophoretic display of claim 4 wherein one of said first, second and third colors is white and the other two colors are green and magenta.

7. The color electrophoretic display of claim 4 wherein one of said first, second and third colors is white and the other two colors are blue and yellow.

8. The color electrophoretic display of claim 3 wherein said first and second species of particles bear charges of opposite polarity.

9. The color electrophoretic display of claim 3 having a first electrode adjacent said viewing surface of said display element and second and third electrodes adjacent said rear surface of said display element, said second and third electrodes occupying less than all of said rear surface of said display element.

10. The color electrophoretic display of claim 3 further comprising:

a second display element having a viewing surface and a rear surface on opposed sides of said second display element, said second display element comprising a plurality of a third species of electrophoretic particles having a fourth color and a plurality of a fourth species of electrophoretic particles having a fifth color different from the fourth color; and

a second colored surface disposed adjacent the rear surface of said second display element, said second colored surface having a sixth color different from said fourth and fifth colors, at least one of the fourth, fifth and sixth colors being different from all of the first, second and third colors,

said second display element having a first state in which said plurality of said third species of particles lie adjacent said viewing surface and said fourth color is displayed, a second state in which said fourth species of particles lie adjacent said viewing surface and said fifth color is displayed, and a third state in which said second colored surface is visible through said viewing surface and said sixth color is displayed.

11. The color electrophoretic display of claim 10 further comprising:

a third display element having a viewing surface and a rear surface on opposed sides of said third display element, said third display element comprising a plurality of a fifth species of electrophoretic particles having a seventh color and a plurality of a sixth species of electrophoretic particles having a eighth color different from the seventh color; and

a third colored surface disposed adjacent the rear surface of said third display element, said third colored surface having a ninth color different from said seventh and eighth colors, at least one of the seventh, eighth and ninth colors being different from all of the first, second, third, fourth, fifth and sixth colors,

said third display element having a first state in which said plurality of said fifth species of particles lie adjacent said viewing surface and said seventh color is displayed, a second state in which said sixth species of particles lie adjacent said viewing surface and said eighth color is displayed, and a third state in which said third colored surface is visible through said viewing surface and said ninth color is displayed.