Touch sensor substrate, touch panel, display device, and method for producing touch sensor substrate

1. A touch sensor substrate, comprising:

a base material having a first surface; and

a plurality of electrodes each having a bottom surface positioned on the first surface, a top surface opposite to the bottom surface, and side surfaces connecting the bottom and top surfaces, each of the electrodes having a blackened layer formed on the side surfaces and at least one of the bottom and top surfaces,

wherein the blackened layer has a surface resistivity of less than 1 Ω/square.

2. The touch sensor substrate of claim 1 , wherein the blackened layer has a thickness of 0.2 μm or less.

3. The touch sensor substrate of claim 1 , wherein the blackened layer has a reflectivity of less than 20% in a visible wavelength range of not less than 400 nm and not more than 780 nm.

4. The touch sensor substrate of claim 2 , wherein the blackened layer has a reflectivity of less than 20% in a visible wavelength range of not less than 400 nm and not more than 780 nm.

5. A touch panel, comprising:

a sensor base including a plurality of first electrodes, a plurality of second electrodes, and a transparent dielectric layer positioned between the first and second electrodes,

wherein the sensor base includes the touch sensor substrate of claim 1 , and the first electrodes and/or the second electrodes are the electrodes of the touch sensor substrate.

6. A touch panel, comprising:

a sensor base including a plurality of first electrodes, a plurality of second electrodes, and a transparent dielectric layer positioned between the first and second electrodes,

wherein the sensor base includes the touch sensor substrate of claim 2 , and the first electrodes and/or the second electrodes are the electrodes of the touch sensor substrate.

7. A touch panel, comprising:

a sensor base including a plurality of first electrodes, a plurality of second electrodes, and a transparent dielectric layer positioned between the first and second electrodes,

wherein the sensor base includes the touch sensor substrate of claim 3 , and the first electrodes and/or the second electrodes are the electrodes of the touch sensor substrate.

8. The touch panel of claim 5 , wherein the sensor base further includes a cover layer forming an operation surface of the sensor base.

9. The touch panel of claim 8 , further comprising:

a peripheral circuit that measures capacitance between the first and second electrodes.

10. The touch panel of claim 6 , wherein the sensor base further includes a cover layer forming an operation surface of the sensor base.

11. The touch panel of claim 10 , further comprising:

a peripheral circuit that measures capacitance between the first and second electrodes.

12. The touch panel of claim 7 , wherein the sensor base further includes a cover layer forming an operation surface of the sensor base.

13. The touch panel of claim 12 , further comprising:

a peripheral circuit that measures capacitance between the first and second electrodes.

14. A display device, comprising:

a display panel that displays information;

the touch panel of claim 9 ; and

a driving circuit that drives the touch panel.

15. A display device, comprising:

a display panel that displays information;

the touch panel of claim 11 ; and

a driving circuit that drives the touch panel.

16. A display device, comprising:

a display panel that displays information;

the touch panel of claim 13 ; and

a driving circuit that drives the touch panel.

17. A method of producing a touch sensor substrate, comprising:

forming a plurality of electrode patterns on a first surface of a base material such that each of the electrodes has a bottom surface positioned on the first surface, a top surface opposite to the bottom surface, and side surfaces connecting the bottom and top surfaces; and

applying a blackening treatment to each of the electrode patterns such that a blackened layer is formed on the side surfaces and at least one of the top and bottom surfaces,

wherein the blackening treatment is one of a black sulfide treatment and a black substitution treatment.

18. The method of claim 17 , wherein the blackening treatment is a black substitution treatment which immerses the electrode patterns in a blackening treatment solution at a temperature of 55° C. or less for 120 seconds or less, and forms the blackened layer having a thickness of 0.2 μm or less on the electrode patterns by a substitution reaction between a metal in the electrode patterns and a Pd ion in the blackening treatment solution.

19. The method of claim 18 , wherein the black substitution treatment immerses the electrode patterns for 10 to 120 seconds in the blackening treatment solution having a temperature of from 35° C. to 5.5° C. and a pH of from 1.5 to 2.5, and including the Pd ion at a concentration of from 100 ppm to 500 ppm.

20. The method of claim 19 , wherein the black substitution treatment immerses the electrode patterns for a period of time adjusted such that a change in wire width of the electrode patterns before and after the black substitution treatment is 0.3 μm or less.

21. The touch sensor substrate of claim 1 , wherein the blackened layer comprises an element selected from the group consisting of Pd, Hg, Ag, Ir, Pt and Au.

22. The touch sensor substrate of claim 1 , wherein the blackened layer comprises Pd.

23. The method of claim 17 , wherein the blackening treatment is a black substitution treatment comprising a substitution reaction between a metal in the electrode patterns and an ion of an element selected from the group consisting of Pd, Hg, Ag, Ir, Pt and Au.

24. The method of claim 17 , wherein the blackening treatment is a black substitution treatment comprising a substitution reaction between a metal in the electrode pattern and a Pd ion.