Components and methods for use in electro-optic displays

• US 7,583,427 B2
• Filed: 09/06/2007
• Issued: 09/01/2009
• Est. Priority Date: 06/10/2002
• Status: Expired due to Term

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: E Ink Holdings Incorporated
• Inventors: Rifai, Sandra, Danner, Guy M., Patry, Shamus Ford, Northrop, Valerie C.
• Primary Examiner(s): Choi; William C
• Application Number:
  US11/850,831
• Publication Number:
  US 20080057252A1
• Time in Patent Office: 726 Days
• Field of Search: 359/245, 359/254, 359/265, 359/273, 359/296
• US Class Current: 359/254
• CPC Class Codes: B32B 38/10 Removing layers, or parts of layers, mechanically or chemically
• CPC Class Codes: G02F 1/133377 Cells with plural compartments or having plurality of liquid crystal microcells partitioned by walls, e.g. one microcell per pixel
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor
• CPC Class Codes: Y10T 156/1062 Prior to assembly
• CPC Class Codes: Y10T 428/1476 Release layer
• CPC Class Codes: Y10T 428/24 Structurally defined web or sheet [e.g., overall dimension, etc.]
• CPC Class Codes: Y10T 428/24479 including variation in thickness

Abstract

A sub-assembly for use in forming an electro-optic display comprises (in this order) a light-transmissive substrate (120); discrete areas (204) of electro-optic material separated by gutter areas (205) essentially free from the electro-optic material; and an adhesive layer (122) and/or a release layer (124) peelable from the sub-assembly. A second sub-assembly comprises (in this order) a peelable release sheet (102); discrete areas of electro-optic material (204) separated by gutter areas (205) essentially free from the electro-optic material, and an adhesive layer (206) and/or a peelable release layer (208). Processes for producing these sub-assemblies and for using them to form electro-optic displays are also described.

Claims

1. A sub-assembly for use in forming an electro-optic display, the sub-assembly comprising:

a light-transmissive substrate;

a plurality of discrete areas of an electro-optic material disposed on the substrate, the discrete areas being separated from each other by gutter areas essentially free from the electro-optic material; and

on the opposed side of the areas of electro-optic material from the substrate, at least one of an adhesive layer and a release layer peelable from the sub-assembly.

2. A sub-assembly according to claim 1 having an adhesive layer in contact with the areas of electro-optic material and a release layer on the opposed side of the adhesive layer from the electro-optic material.

3. A sub-assembly according to claim 1 wherein the at least one of an adhesive layer and a release layer extend across the gutter areas.

4. A sub-assembly according to claim 1 wherein the at least one of an adhesive layer and a release layer do not extend across the gutter areas.

5. A sub-assembly according to claim 1 wherein the substrate comprises a light-transmissive electrically-conductive layer.

6. A sub-assembly according to claim 1 further comprising a removable masking film disposed on the opposed side of the substrate from the electro-optic material.

7. A sub-assembly according to claim 1 further comprising a substrate adhesive layer disposed between the areas of electro-optic material and the substrate, the gutter areas being essentially free from the substrate adhesive layer.

8. A sub-assembly according to claim 1 wherein the electro-optic material comprises a rotating bichromal member or electrochromic material.

9. A sub-assembly according to claim 1 wherein the electro-optic material comprises an electrophoretic material comprising a plurality of electrically charged particles disposed in a fluid and capable of moving through the fluid under the influence of an electric field.

10. A sub-assembly according to claim 9 wherein the electrically charged particles and the fluid are confined within a plurality of capsules or microcells.

11. A sub-assembly according to claim 9 wherein the electrically charged particles and the fluid are present as a plurality of discrete droplets surrounded by a continuous phase comprising a polymeric material.

12. A sub-assembly according to claim 9 wherein the fluid is gaseous.

13. A process for forming a sub-assembly according to claim 1, the process comprising:

forming a plurality of components, each component comprising a layer of electro-optic material and a release layer peelable from the layer of electro-optic material;

disposing the plurality of components on a support surface, the components being spaced from each other, with the layer of electro-optic material facing away from the support surface; and

contacting the disposed plurality of components with a light-transmissive substrate under conditions effective to cause the plurality of components to adhere to the substrate.

14. A process according to claim 13 wherein the support surface comprises a template having a plurality of recesses within which the components are received.

15. A process according to claim 13 wherein each of the components further comprises a substrate adhesive layer disposed on the opposed side of the layer of electro-optic material from the at least one of an adhesive layer and a release layer, and the components are disposed on the support surface with the substrate adhesive layer facing the substrate, so that the substrate adhesive layer acts to adhere the components to the substrate.

16. A process according to claim 13 further comprising:

forming a sub-assembly comprising an adhesive layer on a second substrate; and

after adhering the components to the light-transmissive substrate, removing the release layer from the components, and contacting the components with the adhesive layer on the second substrate under conditions effect to cause the components and the light-transmissive substrate to adhere to the adhesive layer.

17. A process according to claim 13 wherein the substrate comprises a light-transmissive electrically-conductive layer.

18. A process for forming a sub-assembly according to claim 1, the process comprising:

forming a layer of electro-optic material on a release sheet;

severing the layer of electro-optic material on the release sheet to define a plurality of discrete areas separated from each other by gutter areas;

removing the layer of electro-optic material from the gutter areas while leaving the electro-optic material on the release sheet in the plurality of discrete areas; and

after removal of the layer of electro-optic material from the gutter areas, adhering a light-transmissive substrate to the electro-optic material in the plurality of discrete areas.

19. A process according to claim 18 further comprising:

forming an adhesive layer overlying the layer of electro-optic material on the release sheet;

severing both the layer of electro-optic material and the adhesive layer to define the plurality of discrete areas;

removing both the layer of electro-optic material and the adhesive layer from the gutter areas; and

after removal of the layer of electro-optic material and the adhesive layer from the gutter areas, contacting the light-transmissive substrate with the adhesive layer in the plurality of discrete areas, thereby causing the light-transmissive substrate to adhere to the adhesive layer.

20. A process according to claim 19 further comprising:

providing a release layer overlying the adhesive layer on the release sheet;

severing the layer of electro-optic material, the adhesive layer and the release layer to define the plurality of discrete areas; and

removing the release layer from both the plurality of discrete areas and the gutter areas prior to contacting the light-transmissive substrate with the adhesive layer.

21. A process according to claim 20 wherein the removal of the release layer is effected in two stages, with the first stage causing removal of the release layer from the gutter areas, leaving the release layer covering the adhesive layer and the layer of electro-optic material in the plurality of discrete areas, and the second stage causing removal of the release layer from the adhesive layer and the layer of electro-optic material in the plurality of discrete areas.

22. A process according to claim 21 wherein, after severing the layer of electro-optic material, the adhesive layer and the release layer to define the plurality of discrete areas, the portion of the release layer in the gutter areas is first removed, and thereafter a sheet of material is placed over both the plurality of discrete areas and the gutter areas, and the sheet of material is thereafter removed with the portions of the adhesive layer and the electro-optic material from the gutter areas attached thereto, while leaving the adhesive layer and the electro-optic material in the plurality of discrete areas.

23. A process according to claim 22 wherein the removal of the sheet of material also removes the release layer from the plurality of discrete areas.

24. A process according to claim 18 further comprising:

forming a sub-assembly comprising an adhesive layer on a second release sheet; and

after adhering the light-transmissive substrate to the electro-optic material in the plurality of discrete areas, removing the release sheet from the layer of electro-optic material, and contacting the electro-optic material with the adhesive layer of the sub-assembly, thereby adhering the sub-assembly to the layer of electro-optic material.

25. A process according to claim 18 wherein the removal of the layer of electro-optic material from the gutter areas is effected by placing a sheet of material over both the plurality of discrete areas and the gutter areas, and thereafter removing the sheet of material with the portions of the electro-optic material from the gutter areas attached thereto, while leaving the electro-optic material in the plurality of discrete areas.

26. A process according to claim 18 wherein the substrate comprises a light-transmissive electrically-conductive layer.

27. A sub-assembly for use in forming an electro-optic display, the sub-assembly comprising:

a release sheet;

a plurality of discrete areas of an electro-optic material disposed on the substrate, the discrete areas being separated from each other by gutter areas essentially free from the electro-optic material,

the release sheet being peelable from the electro-optic material; and

on the opposed side of the areas of electro-optic material from the substrate, at least one of an adhesive layer and a release layer, the release layer being peelable from the electro-optic material or adhesive layer with which it is in contact.

28. A sub-assembly according to claim 27 having an adhesive layer in contact with the areas of electro-optic material and a release layer on the opposed side of the adhesive layer from the electro-optic material.

29. A sub-assembly according to claim 28 wherein the adhesive and the release layer do not extend across the gutter areas.

30. A sub-assembly according to claim 27 wherein the electro-optic material comprises a rotating bichromal member or electrochromic material.

31. A sub-assembly according to claim 27 wherein the electro-optic material comprises an electrophoretic material comprising a plurality of electrically charged particles disposed in a fluid and capable of moving through the fluid under the influence of an electric field.

32. A sub-assembly according to claim 31 wherein the electrically charged particles and the fluid are confined within a plurality of capsules or microcells.

33. A sub-assembly according to claim 31 wherein the electrically charged particles and the fluid are present as a plurality of discrete droplets surrounded by a continuous phase comprising a polymeric material.

34. A sub-assembly according to claim 31 wherein the fluid is gaseous.