Transparent conductive film and touch panel

• US 6,896,981 B2
• Filed: 07/15/2002
• Issued: 05/24/2005
• Est. Priority Date: 07/24/2001
• Status: Expired due to Fees

• Current Assignee: Bridgestone Corporation
• Original Assignee: Bridgestone Corporation
• Inventors: Kusano, Yukihiro, Yoshikawa, Masato, Kobayashi, Taichi, Iwabuchi, Yoshinori, Ohno, Shingo
• Primary Examiner(s): STEIN, STEPHEN J
• Application Number:
  US10/194,963
• Publication Number:
  US 20030087119A1
• Time in Patent Office: 1,044 Days
• Field of Search: 428/336, 428/446, 428/469, 428/689, 428/697, 428/698, 428/699, 428/701, 428/702, 428/408, 345/173
• US Class Current: 428/698
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact
• CPC Class Codes: Y10T 428/12618 Plural oxides
• CPC Class Codes: Y10T 428/265 1 mil or less
• CPC Class Codes: Y10T 428/2949 Glass, ceramic or metal oxide in coating
• CPC Class Codes: Y10T 428/30 Self-sustaining carbon mass or layer with impregnant or other layer

Abstract

A transparent conductive film has a polymer film 4 and a transparent conductive layer 5 formed on the polymer film 4. The transparent conductive layer includes indium oxide, a zinc oxide system and a tin oxide system. A covering layer 9, made of material different from that of the transparent conductive layer 5, is formed on the transparent conductive layer 5. A touch panel is provided with the transparent conductive film as its upper electrode 6A or lower electrode. The surface of the transparent conductive layer is covered with the covering layer, so that physical or chemical stresses generated during the input to the touch panel do not affect transparent conductive layer directly, thus preventing damages and delamination of the transparent conductive layer. Furthermore, the covering layer formed on the transparent conductive layer improves the strength of the transparent conductive film, thereby enhancing a resistance to wear.

Claims

1. A transparent conductive film comprising:

a polymer film,

a transparent conductive layer formed on the polymer film, and consisting of one of a zinc oxide system and a tin oxide system, and

a covering layer formed on the transparent conductive layer and consisting mainly of at least one material selected from the group consisting of C, CN_x, BN_x, B_xC and SiC_x.

2. A transparent conductive film as claimed in claim 1, wherein the covering layer has a thickness of 0.5 to 100 nm.

3. A transparent conductive film as claimed in claim 1, wherein the covering layer is formed by a physical vapor-depositing process selected from vacuum evaporation process, sputtering process, ion plating process, and laser abrasion process, or by a chemical vapor deposition process.

4. A transparent conductive film as claimed in claim 1, wherein the covering layer is formed by coating a raw liquid for the transparent conductive layer or a solution of the material of the covering layer dissolved in a solvent.

5. A transparent conductive film as claimed in claim 1, wherein a surface of the transparent conductive film where the covering layer is formed has a surface resistivity of 300 to 2000Ω

/Sq. and a linearity value not larger than 1.5%.

6. A transparent conductive film as claimed in claim 1, wherein the transparent conductive layer consists of zinc oxide applied with doping.

7. A transparent conductive film as claimed in claim 6, wherein the transparent conductive layer consists of zinc oxide doped with aluminum.

8. A transparent conductive film as claimed in claim 1, wherein the transparent conductive layer is made of tin oxide or antimony tin oxide.

9. A touch panel provided with a transparent conductive film as claimed in claim 1.

10. A transparent conductive film comprising:

a polymer film,

a transparent conductive layer formed on the polymer film and consisting of one of a zinc oxide system and a tin oxide system, and

a covering layer formed on the transparent conductive layer and consisting of nitride, or oxidized nitride of at least one material selected from the group consisting of Si, Ti, Sn, Nb, In, Mg, Ta and Zn.

11. A touch panel provided with a transparent conductive film as claimed in claim 10.

12. A transparent conductive film comprising:

a polymer film,

a transparent conductive layer formed on the polymer film and consisting of one of a zinc oxide system and a tin oxide system, and

a covering layer formed on the transparent conductive layer, said covering layer being a thin film consisting of SiC_x, SiC_xO_y, SiC_xN_z, or SiC_xO_yN_z deposited by sputtering with an SiC target.

13. A transparent conductive film as claimed in claim 12, wherein the SiC target has a density of not smaller than 2.9 g/cm³.

14. A transparent conductive film as claimed in claim 12, wherein the SiC target is prepared by sintering a mixture of SiC powder and a nonmetal-based sintering assistant.

15. A transparent conductive film comprising:

a polymer film,

a transparent conductive layer formed on the polymer film, and

a covering layer covering the transparent conductive layer, said covering layer being a metal nitriding or oxynitriding layer formed on the transparent conductive layer at a side opposite to the polymer film, said metal nitriding or oxynitriding layer consisting of at least one metal layer selected from the group consisting of Nb, In, Zn, Sn, Co, Pb, W, Zr, and Hf, or including at least one metal selected from the above as a main component.

16. A transparent conductive film as claimed in claim 15, wherein the covering layer is produced by applying heat treatment to the metal layer formed on the transparent conductive layer in an atmosphere of oxygen.

17. A transparent conductive film as claimed in claim 15, wherein the covering layer is produced by applying surface treatment with oxygen plasma and/or nitrogen plasma to the metal layer formed on the transparent conductive layer.

18. A transparent conductive film as claimed in claim 15, wherein the covering layer is formed by a physical vapor-depositing process selected from vacuum evaporation process, sputtering process, ion plating process, and laser abrasion process, or by a chemical vapor-depositing process including CVD.

19. A transparent conductive film as claimed in claim 15, wherein the covering layer has a thickness of 0.5 to 100 nm.

20. A transparent conductive film as claimed in claim 15, wherein a surface of the transparent conductive film where the covering layer is formed thereon has a surface resistivity of 300 to 2000Ω

/Sq. and a linearity value of not larger than 1.5%.

21. A transparent conductive film as claimed in claim 15, wherein the transparent conductive layer has a main component including at least one selected from the group consisting of indium oxide, tin oxide, and zinc oxide.

22. A touch panel provided with a transparent conductive film as claimed in claim 15.