Capacitive touch screen and method of making same

• US 20060266640A1
• Filed: 05/25/2006
• Published: 11/30/2006
• Est. Priority Date: 05/26/2005
• Status: Active Grant

• Current Assignee: TPK Touch Solutions (Xiamen) Inc. (TPK Holding Co., Ltd.)
• Original Assignee: TPK Touch Solutions (Xiamen) Inc. (TPK Holding Co., Ltd.)
• Inventors: Cherif, Mondher, Halsey, Eugene L. IV
• Granted Patent: US 8,354,143 B2
• Time in Patent Office: Days
• US Class Current: 204/192.290
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer

Abstract

A capacitive touch screen and method of manufacturing such a touch screen includes providing a substrate and coating a surface of the substrate with a transparent conductive coating. An uncured conductive electrode material, such as an uncured silver epoxy material or an uncured silver or equivalent conducting metallic paste material, is disposed at least over a portion of the transparent conductive coating to establish a precursor of at least one metallic electrode at the substrate surface. A precursor of a protective hardcoat is established at least over the transparent conductive coating and/or the metallic electrode. Such precursor/undercured/uncured layers are then cured via a single common curing/firing process, which may heat the substrate and coatings to an elevated temperature, such as at about 500 degrees Celsius or above.

Claims

1. A method of manufacturing a touch screen, said method comprising:

providing a substrate;

coating a surface of said substrate with a transparent conductive coating;

disposing an uncured conductive electrode material at least over a portion of said transparent conductive coating to establish a precursor of at least one metallic electrode at said substrate surface;

establishing a precursor of a protective hardcoat at least over at least one of said transparent conductive coating and said metallic electrode; and

curing said protective hardcoat, said transparent conductive coating and said metallic electrode via a common curing and firing process.

2. The method of claim 1, wherein curing said protective hardcoat, said transparent conductive coating and said metallic electrode via a common curing and firing process comprises curing by heating said substrate and said protective hardcoat, said transparent conductive coating and said metallic electrode via a common curing and firing process to an elevated temperature.

3. The method of claim 2, wherein said elevated temperature is at least about 500 degrees Celsius.

4. The method of claim 1, wherein said transparent conductive coating comprises one of an uncured silver epoxy material and an uncured silver.

5. The method of claim 1, wherein said transparent conductive coating comprises an indium tin composition.

6. The method of claim 5, wherein coating a surface of said substrate with a transparent conductive coating comprises coating a surface of said substrate with a transparent conductive coating via coating in a sputter chamber having an atmosphere with reduced oxygen content.

7. The method of claim 6, wherein coating a surface of said substrate with a transparent conductive coating comprises depositing said transparent conductive coating onto a relatively unheated substrate having a temperature of less than about 100 degrees Celsius.

8. The method of claim 1, wherein coating a surface of said substrate with a transparent conductive coating comprises coating a first surface of said substrate with a transparent conductive coating, said method including coating a second surface of said substrate with a second transparent conductive coating, said second surface being opposite said first surface.

9. The method of claim 8 including establishing a metallic coating at a perimeter region of said second surface transparent conductive coating.

10. A method of manufacturing a touch screen, said method comprising:

providing a substrate;

sputter coating a surface of said substrate with a transparent conductive coating comprising an indium tin composition;

disposing an uncured conductive electrode material at least over a portion of said transparent conductive coating to establish a precursor of at least one metallic electrode at said substrate surface;

establishing a precursor of a protective hardcoat at least over at least one of said transparent conductive coating and said metallic electrode; and

curing said protective hardcoat, said transparent conductive coating and said metallic electrode via a common curing and firing process.

11. The method of claim 10, wherein curing said protective hardcoat, said transparent conductive coating and said metallic electrode via a common curing and firing process comprises curing by heating said substrate and said protective hardcoat, said transparent conductive coating and said metallic electrode via a common curing and firing process to an elevated temperature, wherein said elevated temperature is at least about 500 degrees Celsius.

12. The method of claim 10, wherein sputter coating a surface of said substrate with a transparent conductive coating comprises sputter coating a surface of said substrate with a transparent conductive coating via sputter coating in a sputter chamber having an atmosphere with reduced oxygen content.

13. The method of claim 12, wherein sputter coating a surface of said substrate with a transparent conductive coating comprises depositing said transparent conductive coating onto a relatively unheated substrate having a temperature of less than about 100 degrees Celsius.

14. The method of claim 10, wherein sputter coating a surface of said substrate with a transparent conductive coating comprises sputter coating a first surface of said substrate with a transparent conductive coating, said method including coating a second surface of said substrate with a second surface transparent conductive coating, said second surface being opposite said first surface.

15. The method of claim 14 including establishing a metallic coating at a perimeter region of said second surface transparent conductive coating.

16. A method of manufacturing a touch screen, said method comprising:

providing a substrate;

coating a first surface of said substrate with a transparent conductive coating comprising an indium tin composition;

disposing an uncured conductive electrode material at least over a portion of said transparent conductive coating to establish a precursor of at least one metallic electrode at said first surface of said substrate;

establishing a precursor of a protective hardcoat at least over at least one of said transparent conductive coating and said metallic electrode;

coating a second surface of said substrate with a second transparent conductive coating; and

curing said protective hardcoat, said transparent conductive coating and said metallic electrode via a common curing and firing process.

17. The method of claim 16, wherein curing said protective hardcoat, said transparent conductive coating and said metallic electrode via a common curing and firing process comprises curing by heating said substrate and said protective hardcoat, said transparent conductive coating and said metallic electrode via a common curing and firing process to an elevated temperature.

18. The method of claim 16, wherein said transparent conductive coating comprises one of an uncured silver epoxy material and an uncured silver.

19. The method of claim 16, wherein coating a first surface of said substrate with a transparent conductive coating comprises coating a first surface of said substrate with a transparent conductive coating via coating in a sputter chamber having an atmosphere with reduced oxygen content.

20. The method of claim 19, wherein coating a first surface of said substrate with a transparent conductive coating comprises depositing said transparent conductive coating onto a relatively unheated substrate having a temperature of less than about 100 degrees Celsius.