Electroconductive sheet and touch panel

• US 9,055,680 B2
• Filed: 04/29/2014
• Issued: 06/09/2015
• Est. Priority Date: 12/16/2011
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Nakamura, Hiroshige
• Primary Examiner(s): Thompson, Timothy
• Assistant Examiner(s): McAllister, Michael F
• Application Number:
  US14/264,879
• Publication Number:
  US 20140231120A1
• Time in Patent Office: 406 Days
• Field of Search: 345/174, 257/659
• US Class Current: 1/1
• CPC Class Codes: B32B 15/14 next to a fibrous or filamentary layer
• CPC Class Codes: G06F 2203/04112 Electrode mesh in capacitive digitiser: electrode for touch sensing is formed of a mesh of very fine, normally metallic, interconnected lines that are almost invisible to see. This provides a quite large but transparent electrode surface, without need for ITO or similar transparent conductive material
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: H05K 1/0274 Optical details, e.g. printed circuits comprising integral optical means H05K1/0269 takes precedence; coupling light guides with opto-electronic components G02B6/42
• CPC Class Codes: H05K 1/0296 Conductive pattern lay-out details not covered by sub groups H05K1/02 - H05K1/0295 H05K1/11 takes precedence; lay-out adapted to mounted component configuration H05K1/18
• CPC Class Codes: H05K 2201/09245 Crossing layout alternating conductors H05K2201/097

Abstract

The present invention provides an electroconductive sheet and a touch panel which do not impair visibility in a vicinity of an electrode terminal in a sensing region. In an electroconductive sheet which has an electrode pattern constructed of a metal thin wire and an electrode terminal that is electrically connected to an end of the electrode pattern, a transmittance of the electrode pattern is 83% or more, and when the transmittance of the electrode pattern is represented by a %, a transmittance of the electrode terminal is controlled to be (a-20)% or more and (a-3)% or less.

Claims

1. A touch panel having an electroconductive sheet, the electroconductive sheet comprising:

an electrode pattern constructed of a metal thin wire having a line width of 0.7 μ

m or more and 9 μ

m or less, the electrode pattern which is provided in a sensing region; and

an electrode terminal that is electrically connected to an end of the electrode pattern, the electrode terminal which is provided outside of the sensing region, wherein

the electrode terminal includes a mesh shape formed of lattices constructed of a metal thin wire.

2. The touch panel according to claim 1, wherein the metal thin wire constituting the electrode pattern has a line width of 1 μ

m or more and 7 μ

m or less.

3. The touch panel according to claim 1, wherein

the electrode pattern has a mesh shape formed of lattices, and

a pitch of the mesh shape formed of the lattices of the electrode terminal is denser than a pitch of the mesh shape formed of the lattices of the electrode pattern.

4. The touch panel according to claim 3, wherein the pitch of the mesh shape formed of the lattices of the electrode terminal is not larger than ¾

of the pitch of the mesh shape formed of the lattices of the electrode pattern.

5. The touch panel according to claim 3, wherein the pitch of the mesh shape formed of the lattices of the electrode terminal is not larger than ⅔

of the pitch of the mesh shape formed of the lattices of the electrode pattern.

6. The touch panel according to claim 3, wherein the pitch of the mesh shape formed of the lattices of the electrode terminal is not larger than ½

of the pitch of the mesh shape formed of the lattices of the electrode pattern.

7. The touch panel according to claim 1, wherein, in ends of the electrode pattern, another end which is not connected to the electrode terminal is an open end.

8. The touch panel according to claim 1, wherein, in ends of the electrode pattern, another end which is not connected to the electrode terminal has an additional electrode terminal, and

the additional electrode terminal has a mesh shape formed of lattices.

9. The touch panel according to claim 3, wherein the pitch of the mesh shape formed of the lattices of the electrode terminal is 50 μ

m or more and 300 μ

m or less.

10. The touch panel according to claim 1, further comprising

a frame shape constructed of a metal thin wire, the frame shape which is provided as an outer frame of the mesh shape formed of the lattices of the electrode terminal.

11. The touch panel according to claim 10, wherein,

when a line width of the metal thin wire constituting the electrode pattern is represented by A μ

m and a line width of the metal thin wire constituting the frame shape is represented by B μ

m, A and B satisfy a following expression (1);

B≧

2A 

 

(1).

12. The touch panel according to claim 10, wherein,

when a line width of the metal thin wire constituting the electrode pattern is represented by A μ

m and a line width of the metal thin wire constituting the frame shape (64) is represented by B μ

m, A and B satisfy a following expression (2);

B≧

A+5 (μ

m) 

 

(2).

13. The touch panel according to claim 1, wherein a surface resistance value of the electrode terminal is 4 Ω

/sq. or more and 80 Ω

/sq. or less.

14. An electroconductive sheet for a touch panel, comprising:

an electrode pattern that is provided in a sensing region and is constructed of a metal thin wire having a line width of 0.7 μ

m or more and 9 μ

m or less; and

an electrode terminal that is provided in an outside of the sensing region and is electrically connected to an end of the electrode pattern, wherein

the electrode terminal includes a mesh shape formed of lattices constructed of a metal thin wire.

15. The electroconductive sheet for a touch panel according to claim 14, wherein the metal thin wire constituting the electrode pattern has a line width of 1 μ

m or more and 7 μ

m or less.

16. The electroconductive sheet for a touch panel according to claim 14, wherein

the electrode pattern has a mesh shape formed of lattices, and

a pitch of the mesh shape formed of the lattices of the electrode terminal is denser than a pitch of the mesh shape formed of the lattices of the electrode pattern.