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

• US 20090153513A1
• 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 8,253,701 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor
• CPC Class Codes: Y10T 156/1062 Prior to assembly
• CPC Class Codes: Y10T 156/108 Flash, trim or excess removal

Abstract

A touch panel includes a substrate, a transparent conductive layer, and at least two separate electrodes. The transparent conductive layer is formed on a surface of the substrate. The transparent conductive layer includes a carbon nanotube structure comprised of carbon nanotubes, and the carbon nanotubes in the carbon nanotube structure are arranged isotropically, arranged along a same direction, or arranged along different directions. The electrodes are separately located and electrically connected with the transparent conductive layer.

Claims

1. A touch panel comprising:

a substrate;

a transparent conductive layer comprising a carbon nanotube structure comprised of carbon nanotubes, and the carbon nanotubes in the carbon nanotube structure being arranged isotropically, arranged along a same direction, or arranged along different directions; and

at least two separate electrodes electrically connected with the transparent conductive layer.

2. The touch panel as claimed in claim 1, wherein the carbon nanotubes in the carbon nanotube structure are parallel to a major surface of the carbon nanotube structure.

3. The touch panel as claimed in claim 1, wherein an angle between a primary alignment direction of the carbon nanotubes in the carbon nanotube structure and the carbon nanotube structure is 0°

to approximately 15°

.

4. The touch panel as claimed in claim 1, wherein groups of the carbon nanotubes in the carbon nanotube structure are joined end to end by van der Waals attractive force between the ends.

5. The touch panel as claimed in claim 1, wherein the carbon nanotubes in the carbon nanotube structure are selected from a group consisting of single-walled carbon nanotubes, double-walled carbon nanotubes, and multi-walled carbon nanotubes;

and a diameter of the single-walled carbon nanotubes approximately ranges from 0.5 nanometers to 50 nanometers, a diameter of the double-walled carbon nanotubes approximately ranges from 1 nanometer to 50 nanometers, and a diameter of the multi-walled carbon nanotube approximately ranges from 1.5 nanometers to 50 nanometers.

6. The touch panel as claimed in claim 1, wherein the at least two electrodes are separately located on a surface of the transparent conductive layer, and the electrodes comprise of metal.

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

8. The touch panel as claimed in claim 1, further comprising a transparent protective layer located on a surface of the transparent conductive layer, and the material of the transparent protective layer is selected from a 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 located on a surface of the substrate facing away from the transparent conductive layer, and the material of the shielding layer is selected from a group consisting of indium tin oxides, antimony tin oxides, and carbon nanotube films.

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

(a) providing an array of carbon nanotubes, a substrate and at least two electrodes;

(b) forming a carbon nanotube structure; and

(c) electrically connecting the at least two electrodes with the carbon nanotube structure;

wherein forming the carbon nanotube structure comprises pressing the array of carbon nanotubes with a pressing device.

11. The method as claimed in claim 10, wherein step (b) further comprises the substeps of:

(b1) providing a pressing device and an element, pressing the array of carbon nanotubes on the element to form a carbon nanotube film;

(b2) separating the carbon nanotube film and the element;

(b3) cutting the carbon nanotube film into the size of the substrate; and

(b4) adhering the cut carbon nanotube film on the substrate.

12. The method as claimed in claim 10, wherein step (b) further comprises the substeps of:

(b1′

) placing the first surface of the substrate on the array of carbon nanotubes;

(b2′

) using the pressing device to press a second surface of the substrate, to form a carbon nanotube film thereon; and

(b3′

) cutting away residual carbon nanotube film and thus forming the carbon nanotube structure on the substrate.

13. The method as claimed in claim 10, wherein in step (b), the pressing device is a planar pressure head, and the planar pressure head is used to press the array of carbon nanotubes along a direction perpendicular to the substrate.

14. The method as claimed in claim 10, wherein in step (b), the pressing device is a roller-shaped pressure head, and the roller-shaped head is used to press the array of carbon nanotubes along a same direction or along different directions.

15. A display device comprising:

a touch panel comprising;

a substrate;

a transparent conductive layer comprising a carbon nanotube structure comprised of carbon nanotubes, and the carbon nanotubes in the carbon nanotube structure being arranged isotropically, arranged along a same direction, or arranged along different directions; and

at least two separate electrodes electrically connected with the transparent conductive layer; and

a display element positioned adjacent to the touch panel.

16. The display device as claimed in claim 15, 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.

17. The display device as claimed in claim 15, wherein the display element is selected from a group consisting of liquid crystal displays, field emission displays, plasma displays, electroluminescent displays, vacuum fluorescent displays, and cathode ray tubes.

18. The display device as claimed in claim 15, wherein the touch panel is spaced from the display element with a distance.

19. The display device as claimed in claim 15, wherein the touch panel is located on the display element.

20. The display device as claimed in claim 15, further comprising a passivation layer located on a surface of the touch panel, and the material of the passivation layer being selected from the group consisting of silicon nitride and silicon dioxide.