Electrophoretic display layer with thin film top electrode

Patent metadata

Field	Value
Publication number	US-12429744-B2
Application number	US-202318396566-A
Country	US
Kind code	B2
Filing date	Dec 26, 2023
Priority date	Feb 7, 2020
Publication date	Sep 30, 2025
Grant date	Sep 30, 2025

Abstract

A method for making electrophoretic displays layers including various thin films that are deposited directly onto a layer of microcapsules of electrophoretic media. In an embodiment, a thin film of a light-transmissive conductive material is deposited to create a clear front electrode for an electrophoretic display. In some embodiments, both a dielectric layer and a thin film of a light-transmissive conductive material will be deposited onto the microcapsules.

First claim

The invention claimed is:

1. An electrophoretic display layer comprising:
a first substrate;
a layer of capsules comprising electrophoretic media including at least one type of charged particle in a hydrocarbon solvent, where the at least one type of charged particle moves within the capsule in response to an applied electric field, the layer of capsules having a flat side and a contoured side, the capsules being oriented so that the flat side is adjacent the first substrate; and
a 50-200 nm layer of indium tin oxide (ITO) sputtered onto the contoured side of the capsules while the capsules are held at a vacuum pressure of less than 133 Pascal (1 Torr), resulting in a sputtered ITO layer in direct contact with the contoured side of the plurality of capsules,
wherein the layer of capsules is disposed between the first substrate and the sputtered ITO layer.

2. The electrophoretic display layer of claim 1 , wherein the layer of capsules additionally comprises a polyurethane binder between at least some of the capsules within the layer of capsules.

3. The electrophoretic display layer of claim 1 , wherein the first substrate is a release sheet.

4. The electrophoretic display layer of claim 3 , further comprising an adhesive layer between the first substrate and the layer of capsules.

5. The electrophoretic display layer of claim 1 , further comprising a planarizing layer disposed on the sputtered ITO layer.

6. The electrophoretic display layer of claim 5 , further comprising a second substrate disposed on the planarizing layer such that the planarizing layer is disposed between the sputtered ITO layer of light and the second substrate.

7. The electrophoretic display layer of claim 6 , wherein the second substrate is substantially planar.

8. The electrophoretic display layer of claim 1 , further comprising a first layer of dielectric material disposed between the layer of capsules and the sputtered ITO layer.

9. The electrophoretic display layer of claim 8 , wherein the first layer of dielectric material comprises Si 3 N 4 , SiO 2 , Al 2 O 3 , HFO 2 , ZrO 2 , or a polymer.

10. An electrophoretic display comprising the electrophoretic display layer of claim 1 , wherein a second layer of ITO is sputtered between the first substrate and the layer of capsules comprising electrophoretic media.

11. The electrophoretic display of claim 10 , further comprising a second layer of dielectric material disposed between the second layer of sputtered ITO and the layer of capsules.

12. The electrophoretic display of claim 10 , wherein the second layer of dielectric material comprises Si 3 N 4 , SiO 2 , Al 2 O 3 , HFO 2 , ZrO 2 , or a polymer.

13. The electrophoretic display of claim 10 , further comprising a first layer of dielectric material disposed between the layer of capsules and the sputtered ITO layer.

Assignees

• E Ink Corp

Inventors

• Murari Nishit
• Kamaev Pavel
• Miller David Darrell
• Paolini Jr Richard J
• Anseth Jay William

Classifications

• G02F1/16757 Primary

  Microcapsules · CPC title

• G02F1/16756

  Insulating layers · CPC title

• G02F1/167 Primary

  by electrophoresis · CPC title

• G02F1/1676

  Electrodes · CPC title

• G02F1/1303

  Apparatus specially adapted to the manufacture of LCDs · CPC title