Flexible electrode-bearing article

• US 5,738,934 A
• Filed: 10/29/1996
• Issued: 04/14/1998
• Est. Priority Date: 06/06/1995
• Status: Expired due to Term

• Current Assignee: Tyco Electronics Corporation (TE Connectivity Ltd. (United Kingdom))
• Original Assignee: Raychem Limited (TE Connectivity Limited)
• Inventors: Jones, Philip J.
• Primary Examiner(s): Le, H. Thi
• Application Number:
  US08/739,235
• Time in Patent Office: 532 Days
• Field of Search: 428/220, 428/336, 428/412, 428/480, 428/473.5, 428/702, 310/364, 429/42, 429/44, 429/137, 429/193, 429/209, 429/212
• US Class Current: 428/220
• CPC Class Codes: G02F 1/133305 Flexible substrates, e.g. plastics, organic film
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: H01H 13/702 with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches
• CPC Class Codes: H01H 13/785 characterised by the material of the contacts, e.g. conductive polymers
• CPC Class Codes: H01H 2201/032 Conductive polymer; Rubber
• CPC Class Codes: H01H 2209/002 Materials
• CPC Class Codes: Y10T 428/265 1 mil or less
• CPC Class Codes: Y10T 428/31507 Of polycarbonate
• CPC Class Codes: Y10T 428/31721 Of polyimide
• CPC Class Codes: Y10T 428/31786 Of polyester [e.g., alkyd, etc.]

Abstract

An improved electrode for use in displays, including those of the touchscreen type, has a conductive polymeric material disposed over the electrode material at those regions where the electrode is subject to flexing in use, thereby putting the electrode material at risk of cracking. The conductive polymeric material bridges any cracks which may develop, thus providing electrical continuity.

Claims

1. An electrode-bearing article, comprising

a supporting material;

an electrode material disposed over said supporting material, including over a region of said supporting material which is subject to flexing in use, rendering said electrode material susceptible to cracking at such region; and

a conductive polymeric material disposed in contact with said electrode material in said region of said supporting material subject to flexing in use, said conductive polymeric material (a) comprising a blend of an intrinsically conducting polymer and a non-conductive polymer and (b) having a Young'"'"'s modulus of less than 100 kg/cm².

2. An electrode-bearing article according to claim 1, wherein said intrinsically conducting polymer is selected from the group consisting of polypyrrole, polythiophene, polyacetylene, poly(phenylene vinylene), poly(phenylene sulfide), poly(p-phenylene), polyaniline, and poly(heterocycle vinylene).

3. An electrode-bearing article according to claim 2, wherein said intrinsically conducting polymer is polyaniline.

4. An electrode-bearing article according to claim 1, wherein said non-conductive polymer is selected from the group consisting of polyolefins, polystyrene, poly(vinyl chloride), acrylonitrile-butadiene-styrene copolymer, aliphatic polyamide, aromatic polyamide, acrylic polymers, methacrylate polymers, polycarbonate, polysiloxane, polybutadiene, ethylene-vinyl acetate copolymer, elastomers, and fluoropolymers.

5. An electrode-bearing article according to claim 1, wherein the conductive polymeric material has a Young'"'"'s modulus of less than 10 kg/cm².

6. An electrode-bearing article according to claim 1, wherein the conductive polymeric material has a thickness of less than 1 μ

m.

7. An electrode-bearing article according to claim 1, wherein the electrode-bearing article has a flexural stiffness which is less than twice that of the corresponding article without the conductive polymeric material.

8. An electrode-bearing article according to claim 1, wherein said electrode material is selected from the group consisting of indium tin oxide, indium oxide, tin oxide, antimony oxide, gold, gold-nickel, alloy and nickel.

9. An electrode-bearing article according to claim 8, wherein said electrode material is indium tin oxide.

10. An electrode-bearing article according to claim 1, wherein said supporting material is selected from the group consisting of polyester, poly(vinyl chloride), poly(ether sulfone), polycarbonate, polyimide, and poly(ether imide).

11. An electrode-bearing article according to claim 10, wherein said supporting material is poly(ethylene terephthalate).

12. An electrode-bearing article according to claim 1, wherein said supporting material is poly(ethylene terephthalate), said electrode material is indium tin oxide, and said intrinsically conducting polymer is polyaniline.

13. An electrode-bearing article according to claim 1, wherein said conductive polymeric material is disposed substantially over the entire surface of the electrode material.

14. An electrode-bearing article according to claim 13, wherein said conductive polymeric material has a surface resistance greater than 100 ohm/square.

15. An electrode-bearing article according to claim 1, wherein said conductive polymeric material is disposed on the surface of said electrode material away from said supporting material.

16. An electrode-bearing article according to claim 1, wherein said conductive polymeric material is disposed between said electrode material and said supporting material.

17. An electrode-bearing article according to claim 1, wherein the weight ratio of intrinsically conducting polymer to non-conductive polymer is between 99 to 1 and 1 to 99.