Touch panel, method for making the same, and display device adopting the same

• US 20090153504A1
• Filed: 09/29/2008
• Published: 06/18/2009
• Est. Priority Date: 12/14/2007
• Status: Active Grant

• Current Assignee: Hon Hai Precision Industry Co., Ltd., Tsinghua University
• Original Assignee: Hon Hai Precision Industry Co., Ltd., Tsinghua University
• Inventors: Liu, Chang-Hong, Fan, Shou-Shan, Jiang, Kai-Li, Liu, Liang
• Granted Patent: US 8,411,044 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• 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 428/249921 Web or sheet containing structurally defined element or component

Abstract

A touch panel includes a substrate, a transparent conductive layer, and at least two separate electrodes. The substrate includes a first surface. The transparent conductive layer is formed on the first surface of the substrate. The transparent conductive layer includes a carbon nanotube layer, and the carbon nanotube layer includes a plurality of carbon nanotubes entangled with each other. The electrodes are separately disposed on a surface of the transparent conductive layer and electrically connected with the transparent conductive layer. Further, a method for making the touch panel and a display device adopting the same are also included.

Claims

1. A touch panel comprising:

a substrate comprising a first surface;

a transparent conductive layer disposed on the first surface of the substrate, the transparent conductive layer comprising a carbon nanotube layer, the carbon nanotube layer comprising a plurality of carbon nanotubes entangled with each other; and

at least two electrodes disposed on a surface of the transparent conductive layer and electrically connected with the transparent conductive layer.

2. The touch panel as claimed in claim 1, wherein the carbon nanotubes in the carbon nanotube layer are substantially uniform, and lengths of the carbon nanotubes are above 10 micrometers.

3. The touch panel as claimed in claim 2, wherein the adjacent carbon nanotubes are combined and entangled by van der Waals attractive force therebetween, thereby forming an entangled microporous structure.

4. The touch panel as claimed in claim 3, wherein the microporous structure comprises a plurality of micropores, and diameters of the micropores are less than 10 micrometers.

5. The touch panel as claimed in claim 1, wherein the carbon nanotubes in the carbon nanotube layer are selected from the group consisting of single-walled carbon nanotubes, double-walled carbon nanotubes, and multi-walled carbon nanotubes, diameters of the single-walled carbon nanotubes are in an approximate range from 0.5 nanometers to 50 nanometers, diameters of the double-walled carbon nanotubes are in an approximate range from 1 nanometer to 50 nanometers, and diameters of the multi-walled carbon nanotubes are in an approximate range from 1.5 nanometers to 50 nanometers.

6. The touch panel as claimed in claim 1, wherein the electrodes are separately disposed on the surface of the transparent conductive layer facing away from the substrate, and the electrodes are metal electrodes.

7. The touch panel as claimed in claim 6, wherein the electrodes are adhered to the transparent conductive layer using a silver-based slurry.

8. The touch panel as claimed in claim 1, further comprising a transparent protective film disposed on the surface of the transparent conductive layer, wherein a material of the transparent protective film is selected from the group consisting of silicon nitride, silicon dioxide, benzocyclobutenes, polyester film, and polyethylene terephthalate.

9. The touch panel as claimed in claim 1, further comprising a shielding layer disposed on a second surface of the substrate that faces away from the transparent conductive layer, wherein a material of the shielding layer is selected from the group consisting of indium tin oxide, antimony tin oxide, and carbon nanotubes.

10. A method for making a touch panel, the method comprising:

providing a raw material of carbon nanotubes, and a substrate;

flocculating the raw material of carbon nanotubes to acquire a carbon nanotube floccule structure, treating the carbon nanotube floccule structure so as to obtain a carbon nanotube layer, and attaching the carbon nanotube layer on a surface of the substrate; and

providing at least two electrodes, and separately electrically connecting the at least two electrodes with the carbon nanotube layer.

11. The method as claimed in claim 10, wherein the flocculating of the raw material of carbon nanotubes comprises:

adding the raw material of carbon nanotubes to a solvent to obtain a floccule structure of carbon nanotubes; and

pump filtrating the floccule structure of carbon nanotubes to obtain a carbon nanotube layer.

12. The method as claimed in claim 11, wherein the pump filtrating comprises:

providing a microporous membrane and an air-pumping funnel;

filtering the solvent containing the floccule structure of carbon nanotubes through the microporous membrane into the air-pumping funnel; and

air-pumping and drying the floccule structure of carbon nanotubes captured on the microporous membrane.

13. The method as claimed in claim 10, wherein the flocculating of the raw material of carbon nanotubes comprises:

adding the raw material of carbon nanotubes to a solvent to obtain a floccule structure of carbon nanotubes;

separating the floccule structure of carbon nanotubes from the solvent; and

shaping the separated carbon nanotube floccule structure into the carbon nanotube layer.

14. The method as claimed in claim 13, wherein the separating of the floccule structure of carbon nanotubes from the solvent comprises:

pouring the solvent containing the floccule structure of carbon nanotubes through a filter into a funnel; and

drying the floccule structure of carbon nanotubes on the filter to obtain the separated floccule structure of carbon nanotubes.

15. The method as claimed in claim 13, wherein the shaping of the separated floccule structure of carbon nanotubes into the carbon nanotube layer comprises:

putting the separated floccule structure into a container, and spreading the floccule structure to form a spread floccule structure;

pressing the spread floccule structure with a certain pressure to yield a desirable shape; and

drying the spread floccule structure to remove the residual solvent, or volatilizing the residual solvent, to form the carbon nanotube layer.

16. A display device comprising:

a touch panel comprising;

a substrate, comprising a first surface;

a transparent conductive layer disposed on the first surface of the substrate, the transparent conductive layer comprising a carbon nanotube layer, the carbon nanotube layer comprising a plurality of carbon nanotubes entangled with each other; and

at least two electrodes disposed on a surface of the transparent conductive layer, and electrically connected with the transparent conductive layer; and

a display element positioned opposite and adjacent to the touch panel.

17. The display device as claimed in claim 16, further comprising a touch panel controller, a central processing unit, and a display element controller electrically connected with each other, the touch panel controller being connected to the touch panel, and the display element controller being connected to the display element.

18. The display device as claimed in claim 16, wherein the display element is selected from the group consisting of liquid crystal displays, field emission displays, plasma displays, electroluminescent displays, vacuum fluorescent displays, and cathode ray tubes.

19. The display device as claimed in claim 16, wherein the touch panel is one of spaced at a distance from the display element and installed on the display element.

20. The display device as claimed in claim 16, further comprising a passivation layer disposed on a surface of the touch panel, the passivation layer positioned opposite and adjacent to the display element, and the passivation layer being comprised of one of silicon nitride and silicon dioxide.