Method of manufacturing a touch screen panel

• US 20030001826A1
• Filed: 08/20/2002
• Published: 01/02/2003
• Est. Priority Date: 06/20/2001
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Bottari, Frank J., Richter, Paul J., Kardauskas, Michael J.
• Granted Patent: US 6,842,171 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0444 using a single conductive element covering the whole sensing surface, e.g. by sensing the electrical current flowing at the corners
• CPC Class Codes: Y10T 428/24777 Edge feature
• CPC Class Codes: Y10T 428/24917 including metal layer

Abstract

A method of manufacturing a touch screen panel, the method including applying a resistive coating to one surface of an insulative substrate, applying an insulative protective coating to the resistive coating, depositing a conductive edge electrode pattern including a plurality of edge electrodes on the protective coating, and firing the panel until the edge electrodes etch through the protective coating and make electrical contact with the resistive coating.

Claims

1. A touch screen panel comprising:

an insulative substrate;

a resistive coating on one surface of the substrate;

a protective coating on the resistive coating; and

a conductive edge electrode pattern including a plurality of edge electrodes on the protective coating and extending to the resistive coating and making electrical contact therewith.

2. The panel of claim 1 in which the material of the edge electrodes includes conductive paste mixed with an additive.

3. The panel of claim 2 in which the insulative protective coating includes silicon dioxide and the additive includes a chemical compound which is converted into a molten alkali hydroxide at elevated temperatures which dissolves the silicon dioxide of the protective coating.

4. The panel of claim 3 in which the chemical compound is selected from the group consisting of sodium carbonates and/or sodium formates.

5. The panel of claim 2 in which the conductive paste is a silver/frit composition.

6. The panel of claim 2 in which the additive comprises 1-25% by weight of the conductive paste.

7. The panel of claim 1 in which the resistive coating is applied by methods selected from the group consisting of sputtering, evaporation, chemical vapor deposition, meniscus coating, dip coating, screen printing, and pad printing.

8. The panel of claim 1 in which the insulative protective coating is applied by a method selected from the group consisting of dip coating, meniscus coating, sputtering, evaporation, chemical vapor deposition, screen printing, and pad printing.

9. The panel of claim 1 in which the insulative protective coating is cured before the conductive edge electrode pattern is deposited thereon.

10. The panel of claim 1 further including a wire trace pattern deposited on the protective coating, etched through the protective coating, and making electrical contact with the resistive coating.

11. The panel of claim 10 in which the material of the wire trace pattern includes conductive paste mixed with an additive.

12. The panel of claim 11 in which the insulative protective coating includes silicon dioxide and the additive includes a chemical compound which is converted into a molten alkali hydroxide at elevated temperatures which dissolves the silicon dioxide of the protective coating.

13. The panel of claim 1 further including a wire trace pattern on the protective coating.

14. The panel of claim 13 further including electrical isolation between the wire trace pattern and the edge electrodes.

15. The panel of claim 14 further including a dielectric material between the wire trace pattern and the protective coating.

16. The panel of claim 14 further including a dielectric material over the conductive edge electrode pattern and a wire trace pattern on the dielectric material.