KR20140013350A - Touch panel and method for manufacturing the same - Google Patents

Abstract

A touch panel according to an embodiment comprises a transparent electrode disposed on a substrate and sensing an input location. The transparent electrode includes a first transparent electrode unit and a second transparent electrode unit positioned on the first transparent electrode unit. The second transparent electrode unit surrounds the first transparent electrode unit. A touch panel manufacturing method according to an embodiment comprises a step of forming the transparent electrode on the substrate. The step of forming the transparent electrode includes a step of forming the first transparent electrode unit and a step of forming the second transparent electrode unit surrounding the first transparent electrode unit.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a touch panel,

The present invention relates to a touch panel and a manufacturing method thereof.

2. Description of the Related Art In recent years, a touch panel has been applied to an image displayed on a display device in various electronic products by a method of touching an input device such as a finger or a stylus.

The touch panel can be largely divided into a resistance film type touch panel and a capacitive type touch panel. In the resistive touch panel, the glass and the electrode are short-circuited by the pressure of the input device and the position is detected. A capacitance type touch panel senses a change in electrostatic capacitance between electrodes when a finger touches them, thereby detecting the position.

The resistance film type touch panel may be deteriorated in performance by repeated use, and scratch may occur. As a result, there is a growing interest in a capacitive touch panel having excellent durability and long life span.

Indium tin oxide (ITO), which is widely used as a transparent electrode of the touch panel, is expensive and requires high temperature deposition and vacuum process to form the electrode. In addition, there is a problem that physically easily hit by the bending and bending of the substrate to deteriorate the characteristics to the electrode, thereby not suitable for flexible elements. In addition, when applied to a large size touch panel, a problem arises due to high resistance.

In order to solve such problems, active researches on alternative electrodes are under way.

Embodiments provide a touch panel with improved reliability and a method of manufacturing the same.

The touch panel according to the embodiment includes a transparent electrode disposed on a substrate and sensing an input position, wherein the transparent electrode includes a first transparent electrode part and a second transparent electrode part positioned on the first transparent electrode part. And the second transparent electrode part surrounding the first transparent electrode part. [First transparent electrode part → 1st transparent electrode pattern / 2nd transparent electrode part → 2nd transparent electrode pattern change examination whether necessary]

A method of manufacturing a touch panel according to an embodiment includes forming a transparent electrode on the substrate, wherein forming the transparent electrode includes forming a first transparent electrode part and surrounding the first transparent electrode part. Forming a second transparent electrode part.

The transparent electrode of the touch panel according to the embodiment includes a first transparent electrode portion and a second transparent electrode portion. The first transparent electrode portion may include a printable metal paste material. This is a substitute for indium tin oxide (ITO), which is advantageous in terms of price and can be formed by a simple process.

The first transparent electrode part has a mesh shape. The first transparent electrode part is used as a seed layer for forming the second transparent electrode part.

 The second transparent electrode part may cover the side surface and the top surface of the first transparent electrode part. In addition, the second transparent electrode part may fill the cracked portions of the first transparent electrode part. That is, when the internal filling rate of the first transparent electrode portion is low, cracks are generated, which can be reinforced through the second transparent electrode portion. Through this, it is possible to prevent an electrical short circuit and have a higher electrical conductivity improvement effect. Therefore, it can be applied to large size touch panel products.

In the method for manufacturing a touch panel according to the embodiment, the first transparent electrode portion is formed by a printing process and the second transparent electrode portion is formed by a plating process, thereby simplifying the process. In particular, by forming the first transparent electrode portion in the printing process, it is possible to reduce the manufacturing cost compared to the existing process.

1 is a schematic plan view of a touch panel according to an embodiment.
2 is a plan view showing an enlarged view of FIG.
3 is a cross-sectional view showing a section cut along the line B-B 'in Fig.
4 to 5 are plan views and cross-sectional views illustrating a method of manufacturing a touch panel according to an embodiment.
6 is a view for explaining a method of manufacturing a touch panel according to an embodiment.

In the description of the embodiments, it is to be understood that each layer (film), area, pattern or structure may be referred to as being "on" or "under / under" Quot; includes all that is formed directly or through another layer. The criteria for top / bottom or bottom / bottom of each layer are described with reference to the drawings.

The thickness or the size of each layer (film), region, pattern or structure in the drawings may be modified for clarity and convenience of explanation, and thus does not entirely reflect the actual size.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, a touch panel according to an embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is a schematic plan view of a touch panel according to an embodiment. 2 is a plan view showing an enlarged view of FIG. 3 is a cross-sectional view taken along the line BB ′ of FIG. 2.

1 to 3, the touch panel according to the present exemplary embodiment includes an effective area AA that detects a position of an input device (for example, a finger, etc.) and a peripheral area disposed around the effective area AA. The substrate 100 includes an ineffective area UA.

Here, the transparent electrode 210 may be formed on the effective area AA to sense the input device. A wiring 300 electrically connecting the transparent electrode 210 may be formed in the ineffective area UA. An external circuit or the like connected to the wiring 300 may be located in the ineffective area UA. The outer dummy layer 101 may be formed in the ineffective area UA and the logo 102 may be formed on the outer dummy layer 101.

When such an input device such as a finger touches the touch panel, a difference in capacitance occurs at a portion where the input device is contacted, and a portion where the difference occurs can be detected as the contact position.

The touch panel will be described in more detail as follows.

The substrate 100 may be formed of various materials capable of supporting the transparent electrode 210, the wiring 300, and the circuit substrate formed thereon. The substrate 100 may be a glass substrate or a plastic substrate, for example.

The outer dummy layer 101 is formed in the ineffective area UA of the substrate 100. [ The outer dummy layer 101 may be formed by applying a material having a predetermined color so that the wiring 300 and a printed circuit board connecting the wiring 300 to an external circuit can not be seen from the outside. The outer dummy layer 101 may have a color suitable for a desired appearance, for example, a black pigment including black pigment and the like. A desired logo 102 or the like can be formed on the outer dummy layer 101 by various methods. The outer dummy layer 101 may be formed by vapor deposition, printing, wet coating or the like.

The transparent electrode 210 may be formed on the substrate 100. The transparent electrode 210 may sense whether an input device such as a finger is in contact.

Referring to FIG. 2, the transparent electrode 210 includes a first electrode 212 and a second electrode 214.

The first electrode 212 includes a plurality of first sensor portions 212a for sensing whether an input device such as a finger is contacted and a first connection electrode portion 212b for connecting the plurality of first sensor portions 212a. . The first connection electrode part 212b connects the plurality of first sensor parts 212a in a first direction (X axis direction in the drawing), and the first electrode 212 extends in the first direction .

Similarly, the second electrode 214 includes a plurality of second sensor units 214a for sensing whether an input device such as a finger is contacted, and a second connection electrode 214a for connecting the plurality of second sensor units 214a. And a portion 214b. The second connection electrode portion 214b connects the plurality of second sensor portions 214a in a second direction (Y-axis direction in the drawing) intersecting the first direction, and the second electrode 214 And extend in the second direction.

An insulating layer 250 may be disposed between the first connection electrode part 212b and the second connection electrode part 214b to prevent an electrical short circuit. The insulating layer 250 may include a transparent insulating material capable of insulating the first electrode 212 and the second electrode 214.

Meanwhile, the transparent electrode 210 may include two or more layers. In this case, each of the layers may be formed of the same material or different materials.

Specifically, referring to FIG. 3, the transparent electrode 210 includes a first transparent electrode portion 216 and a second transparent electrode portion 218.

The first transparent electrode part 216 is positioned on the substrate 100. The first transparent electrode unit 216 may directly contact the substrate 100.

The first transparent electrode unit 216 may include a printable metal paste material. By forming a fine wire width mesh with a metal paste, it is possible to replace the existing indium tin oxide (ITO), which is advantageous in terms of cost and can be formed by a simple printing process. The first transparent electrode unit 216 may include various metal pastes such as Ag, Cu, Al, and Cr.

The first transparent electrode part 216 has a mesh shape. Since the first transparent electrode part 216 has a mesh shape, the pattern of the first transparent electrode part 216 may not be visible on the effective area AA. In addition, even when the first transparent electrode unit 216 is applied to a large size touch panel, the resistance of the touch panel may be lowered due to the excellent electrical conductivity of the metal. In addition, when the first transparent electrode unit 216 is formed by a printing process, it is possible to secure a high quality touch panel by improving printing quality.

The first transparent electrode portion 216 is formed by printing a printing ink. Since the density of the metal particles in the printing ink is very low, such as 20% to 30%, the thickness T1 of the first transparent electrode portion 216 is reduced. Is very thin, below 100 nm.

The metal mesh line width of the first transparent electrode unit 216 may be 1 μm to 5 μm. The spacing of the lines may be between 100 μm and 500 μm. Specifically, the maximum line width W of the first transparent electrode part 216 may be 1 μm to 5 μm. When the line width W of the first transparent electrode unit 216 is 1 μm or more, the transparent electrode 210 of the touch panel may have electrical conductivity required. When the line width W of the first transparent electrode portion 216 is 5 μm or less, the pattern of the first transparent electrode portion 216 may be fine to improve visibility of the touch panel.

Subsequently, the second transparent electrode part 218 may be located on the first transparent electrode part 216. The first transparent electrode part 216 and the second transparent electrode part 218 may be in contact with each other up and down.

In addition, the second transparent electrode unit 218 may surround the first transparent electrode unit 216. The second transparent electrode part 218 may cover the side surface and the top surface of the first transparent electrode part 216. Accordingly, the second transparent electrode part 218 may directly contact the first transparent electrode part 216.

In addition, the second transparent electrode part 218 may fill the divided portions of the first transparent electrode part 216. That is, when the internal filling rate of the first transparent electrode portion 216 is low, cracks are generated, which can be reinforced through the second transparent electrode portion 218. Through this, it is possible to prevent an electrical short circuit and have a higher electrical conductivity improvement effect.

The second transparent electrode part 218 may include a metal. The second transparent electrode part 218 may include a metal that can be formed by plating. For example, the second transparent electrode part 218 may be formed of gold (Au), copper (Cu), silver (Ag), platinum (Pt), nickel (Ni), palladium (Pd), cobalt (Co), or stanium. (Sn) may be included.

The thickness T2 of the second transparent electrode part 218 may be 50 nm to 200 nm. When the thickness T2 of the second transparent electrode part 218 is thicker than 50 nm, the second transparent electrode part 218 may greatly contribute to improving the electrical conductivity of the transparent electrode 210. When the thickness T2 of the second transparent electrode part 218 is thinner than 200 nm, the line width of the transparent electrode 210 can be kept fine, and the pattern is not visually confirmed, thereby improving the visibility of the touch panel. Can be. The thickness T2 of the second transparent electrode part 218 may be maintained by controlling the plating time.

Subsequently, the wiring 300 is formed in the ineffective area UA. The wire 300 may apply an electrical signal to the transparent electrode 210. The wiring 300 may be formed in the ineffective area UA so as not to be seen.

Although not shown in the drawings, a circuit board connected to the wiring may be further located. Various types of printed circuit boards may be used as the circuit board. For example, a flexible printed circuit board (FPCB) may be applied.

Hereinafter, a method of manufacturing a touch panel according to an embodiment will be described with reference to FIGS. 4 to 6. For the sake of clarity and conciseness, the same or similar parts as those described above will not be described in detail.

4 to 5 are plan views and cross-sectional views illustrating a method of manufacturing a touch panel according to an embodiment. In particular, FIGS. 4 to 5 are plan and cross-sectional views illustrating an enlarged portion C of FIG. 2. 6 is a view for explaining a method of manufacturing a touch panel according to an embodiment.

First, referring to FIG. 4, a substrate 100 may be prepared and a transparent electrode may be formed on the substrate 100. In detail, the first transparent electrode part 216 may be formed on the substrate 100.

The first transparent electrode unit 216 may be formed through a printing process. For example, the first transparent electrode unit 216 may be formed through an offset printing process. In particular, when using a reverse off set printing process, a fine pattern can be printed. That is, it can be formed while ensuring the print quality of the first transparent electrode portion 216 having a mesh shape. In addition, compared to the conventional photolithography process, the process can be simplified and manufacturing costs can be reduced.

However, printing is performed by using a printing ink to form the first transparent electrode portion 216. Since the density of the metal particles in the printing ink is very low, such as 20% to 30%, the thickness T1 of the actual printing pattern is 100. There is a problem that it is very thin below nm, which makes it difficult to obtain sufficient electrical conductivity. In addition, when the internal filling rate of the first transparent electrode portion 216 formed as described above is very low, cracking or gaps may occur. In order to compensate for this, the second transparent electrode part 218 is further formed.

After printing the first transparent electrode unit 216, it may be sintered at a high temperature.

Subsequently, the step of catalysis may be performed. Palladium (Pd) may be catalytically treated on the surface of the first transparent electrode unit 216.

Subsequently, referring to FIG. 5, the second transparent electrode part 218 may be formed. The first transparent electrode part 216 may be formed by plating using the seed layer. In this case, the second transparent electrode part 218 may be formed by electroplating or electroless plating.

Electroplating is a method of forming a thin film of metal on the surface of an object using the principle of electrolysis.

Referring to FIG. 6, first, a plating solution 30 is prepared in a water tank. The plating solution 30 may be an electrolytic solution, for example, copper sulfate. The substrate 100 and the anode 20 on which the first transparent electrode part 216 is formed are immersed in the plating solution 30. A cathode (−) is connected to the substrate 100 serving as a cathode and a cathode (+) is connected to the anode 20. Thereafter, current is supplied to the substrate 100 and the anode 20. Plating is performed on the surface of the substrate 100 by energizing the substrate 100 and the anode 20.

In the anode 20, hydrogen (H2) is electrolyzed to generate electrons (e-), and the plating solution 30 is decomposed into copper ions (Cu + 2) and sulfate ions (SO4-2). The electrons (e−) of the anode are moved to the cathode and react with copper ions (Cu + 2) to plate copper (Cu) on the substrate 100. Specifically, copper is plated on a portion corresponding to the first transparent electrode 216 to form a second transparent electrode 218. The second transparent electrode part 218 may be plated on the top and side surfaces of the first transparent electrode part 216 to improve electrical conductivity. In addition, the second transparent electrode part 218 may fill a cracked portion of the first transparent electrode part 216 to implement a higher electrical conductivity and prevent an electrical short circuit. Therefore, it can be applied to large size touch panel products.

However, embodiments are not limited thereto, and various materials may be plated on the substrate 100 through various plating solutions 30.

In this case, the plating time may be controlled so that the thickness of the second transparent electrode part 218 may be 50 nm to 200 nm.

Subsequently, although not shown in the drawings, wirings, circuit boards, and the like can be formed.

In the method of manufacturing a touch panel according to the embodiment, the first transparent electrode portion 216 is formed by a printing process, and the second transparent electrode portion 218 is formed by a plating process, thereby simplifying the process.

The features, structures, effects and the like described in the foregoing embodiments are included in at least one embodiment of the present invention and are not necessarily limited to one embodiment. Further, the features, structures, effects, and the like illustrated in the embodiments may be combined or modified in other embodiments by those skilled in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limiting the scope of the present invention. It can be seen that various modifications and applications are possible. For example, each component specifically shown in the embodiments may be modified and implemented. It is to be understood that the present invention may be embodied in many other specific forms without departing from the spirit or essential characteristics thereof.

Claims (16)

A transparent electrode disposed on the substrate, the transparent electrode sensing an input position;
The transparent electrode includes a first transparent electrode portion and a second transparent electrode portion located on the first transparent electrode portion,
The second transparent electrode unit surrounds the first transparent electrode unit. The method of claim 1,
The second transparent electrode part covers the top and side surfaces of the first transparent electrode part. The method of claim 1,
And the first transparent electrode portion includes a gap, and the second transparent electrode portion fills the gap. The method of claim 1,
The first transparent electrode unit has a mesh shape. The method of claim 1,
The first transparent electrode unit comprises a metal. The method of claim 1,
The second transparent electrode part in the group consisting of gold (Au), copper (Cu), silver (Ag), platinum (Pt), nickel (Ni), palladium (Pd), cobalt (Co) and stanium (Sn) A touch panel comprising at least one selected material. The method of claim 1,
The line width of the first transparent electrode part is 1 μm to 5 μm. The method of claim 1,
The line between the line and the line of the first transparent electrode portion is 100 ㎛ to 500 ㎛ touch panel. The method of claim 1,
The thickness of the second transparent electrode part is 200 nm to 300 nm. Preparing a substrate; And
Forming a transparent electrode on the substrate;
Forming the transparent electrode
Forming a first transparent electrode part and forming a second transparent electrode part surrounding the first transparent electrode part. 11. The method of claim 10,
The forming of the first transparent electrode unit may include a printing process. 11. The method of claim 10,
The forming of the first transparent electrode unit may include an offset printing process. 11. The method of claim 10,
The forming of the second transparent electrode part includes a plating process. 11. The method of claim 10,
The forming of the second transparent electrode part may include plating the first transparent electrode part using a seed layer. 11. The method of claim 10,
The forming of the second transparent electrode part may be performed by electroplating or electroless plating. 11. The method of claim 10,
A method of manufacturing a touch panel further comprising the step of catalyzing the step of forming the first transparent electrode portion and the step of forming the second transparent electrode portion.

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