KR102275704B1 - Touch panel and manufacturing method thereof - Google Patents

Abstract

The present invention discloses a touch panel and a method for manufacturing the same. The disclosed touch panel of the present invention includes a touch electrode formed in a touch mesh pattern on a substrate, and the touch mesh pattern is characterized in that it consists of a plurality of nanowires and a coating layer formed on the nanowires.
Therefore, the touch panel and its manufacturing method according to the present invention have low resistance, no RC delay time, no pattern recognized by the naked eye, and can be applied to a large area. In addition, the moire phenomenon is improved by using nanowires, the milky phenomenon is improved by forming a mesh pattern, and a coating layer is formed on the nanowires to reduce the resistance generated in the nanowire overlapping area, and improve the adhesion of the nanowires. can do it Such a touch panel and a method for manufacturing the same can be applied to a flexible display device.

Description

Touch panel and manufacturing method thereof

The present invention relates to a touch panel and a method for manufacturing the same, and more particularly, to prevent a milky phenomenon and a moire phenomenon, to be applied to a large area with low resistance, and to be applicable to a flexible display device. It relates to a touch panel having a touch electrode and a method for manufacturing the same.

Recently, as the information society develops, the demand for the display field is also increasing in various forms, and in response to this, various flat panel display devices with characteristics such as thinness, light weight, and low power consumption, for example, liquid crystal A liquid crystal display device, a plasma display panel device, an electroluminescent display device, and the like are being studied.

In addition, a touch panel as an input device that is attached to the display device and allows a user's command to be input by selecting instructions displayed on a screen with a human hand or an object is in the spotlight. The touch panel is provided on the front face of the display device and converts a contact position in direct contact with a person's hand or an object into an electrical signal.

Accordingly, the instruction content selected at the contact position is accepted as an input signal. Since such a touch panel can replace a separate input device connected to an image display device and operated, such as a keyboard and a mouse, the range of its use is gradually expanding.

Since the electrode of the touch panel should be formed on the front surface of the display device, indium doped tin oxide (ITO) is generally used as a well-known transparent electrode. However, in the case of the ITO electrode, there are many problems. First, the ITO electrode exhibits high resistance characteristics. Due to such a high resistance, the ITO electrode has a limitation of increasing the area, and an RC delay time that is affected by the resistance (R) and the capacitance (C) occurs.

In addition, the ITO electrode has a problem in that the pattern is recognized with the naked eye due to a difference in reflectance at the boundary of the electrode. In addition, since the ITO electrode is a hard material, it is difficult to apply it to a display device including a curved panel that maintains a constant curvature in the configuration of the display device, and a flexible display device formed using a flexible material such as plastic. There is this. In addition, since the scarcity of the indium material constituting ITO and the vacuum process such as sputtering or chemical vapor deposition are essential for ITO coating, the manufacturing process cost is relatively high.

In order to improve the problems of these ITO electrodes, a metal mesh (mesh) pattern electrode has been studied. However, the metal mesh pattern electrode has a problem in that a moire phenomenon occurs. The metal mesh pattern formed in micrometers (㎛) cannot avoid the moire phenomenon due to the total reflection characteristics of the metal.

In addition, a silver (Ag) nanowire electrode may be used to improve the problems of the ITO electrode. Electrodes using silver nanowires have advantages in that silver nanowires are networked and connected to each other like a mesh, and can maintain high electrical conductivity and transparency of 80 to 90% or more.

However, the silver nanowire electrode exhibits high haze characteristics. This haze characteristic is high, and at the same time, light scattering occurs on the curved surface of the nanowire, resulting in a milky phenomenon. The milky phenomenon is a phenomenon in which light is reflected from the silver nanowire and thus complete black is not achieved in a black state.

In addition, contact resistance occurs in the region where the silver nanowires overlap. That is, there is a problem in that the overlapping nanowires are not recognized as a single material, and each nanowire is recognized as a single material, resulting in resistance in the overlapping region.

An object of the present invention is to provide a touch panel having a low resistance, no RC delay time, a pattern not recognized by the naked eye, and applicable to a large area, and a method for manufacturing the same.

In addition, the present invention improves the moire phenomenon by using a nanowire, improves the milky phenomenon by forming a mesh pattern, and reduces the resistance generated in the nanowire overlapping area by forming a coating layer on the nanowire, Another object of the present invention is to provide a touch panel including a touch electrode having improved adhesion and a method for manufacturing the same.

Another object of the present invention is to provide a touch panel applicable to a flexible display device and a method for manufacturing the same.

The touch panel of the present invention for solving the problems of the prior art as described above includes a touch electrode formed in a touch mesh pattern on a substrate, and the touch mesh pattern includes a plurality of nanowires and a coating layer formed on the nanowires. characterized by being made.

In addition, the manufacturing method of the touch panel of the present invention comprises the steps of forming a nanowire on a substrate; forming a coating layer on the nanowire; and forming a touch mesh pattern by etching the nanowire and the coating layer, and forming a touch electrode including the touch mesh pattern.

The touch panel and its manufacturing method according to the present invention have a first effect that has a low resistance, no RC delay time, a pattern is not recognized with the naked eye, and can be applied to a large area.

In addition, the touch panel and its manufacturing method according to the present invention improve the moire phenomenon by using nanowires, improve the milky phenomenon by forming a mesh pattern, and form a coating layer on the nanowires to occur in the overlapping area of the nanowires There is a second effect including a touch electrode that reduces the resistance and improves the adhesion of the nanowire.

In addition, the touch panel and the method for manufacturing the same according to the present invention have a third effect that can be applied to a flexible display device.

1 is a view showing a touch panel according to a first embodiment of the present invention.
2 is a diagram illustrating a touch electrode according to a first embodiment of the present invention.
3 is a diagram illustrating a touch panel according to a second embodiment of the present invention.
4 is a diagram illustrating a touch electrode according to a second embodiment of the present invention.
5 is a diagram illustrating a plan view of a touch mesh pattern according to a third embodiment of the present invention.
6 is a cross-sectional view illustrating a touch mesh pattern according to a third embodiment of the present invention.
7A to 7D are diagrams illustrating a method of manufacturing a touch mesh pattern according to a third embodiment of the present invention.
8 is a diagram illustrating a plan view of a touch mesh pattern according to a fourth embodiment of the present invention.
9 is a diagram illustrating a cross-sectional view of a touch mesh pattern according to a fourth embodiment of the present invention.
10A and 10B are diagrams illustrating a method of manufacturing a touch mesh pattern according to a fourth embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The embodiments introduced below are provided as examples so that the spirit of the present invention can be sufficiently conveyed to those skilled in the art. Accordingly, the present invention is not limited to the embodiments described below and may be embodied in other forms. And in the drawings, the size and thickness of the device may be exaggerated for convenience. Like reference numerals refer to like elements throughout.

1 is a view showing a touch panel according to a first embodiment of the present invention.

Referring to FIG. 1 , a first touch electrode Tx and a second touch electrode Rx are formed on a transparent substrate 30 . In addition, a connection wire 20 connecting the first and second touch electrodes Tx and Rx to the pad electrode is formed. That is, the first touch electrode Tx and the second touch electrode Rx may receive a signal from an external device or externally apply a signal through the pad electrode and the connection wire 20 .

The substrate 30 is formed of a transparent material, and may be formed of glass as an insulating substrate. In addition, in order to be applied to a flexible display device, it may be formed of a material having flexible characteristics, such as plastic or a metal thin film.

The first touch electrode Tx and the second touch electrode Rx may include a sensor unit formed in a rhombus shape. In addition, it may include a connection part having a bridge structure that connects the rhombus-shaped sensor part. The sensor units of the first touch electrode Tx and the second touch electrode Rx may be formed to have the same size or different sizes.

Since the first touch electrode Tx and the second touch electrode Rx, which are electrode portions of the touch panel, include the sensor portion having a rhombus structure, the electrode portion may be formed on the end surface of the substrate 30 . When the first touch electrode Tx and the second touch electrode Rx are formed on the end surface of the substrate 30 , the touch panel may be thinly formed. Also, the touch panel according to the present invention can be applied to a flexible display device.

The first touch electrode Tx and the second touch electrode Rx may be formed in a touch mesh pattern. The following is a detailed review of this by expanding area A.

2 is a diagram illustrating a touch electrode according to a first embodiment of the present invention.

Referring to FIG. 2 , the first touch electrode Tx and the second touch electrode Rx include a rhombus-shaped sensor unit and a bridge structure connecting the sensor unit. The rhombus-shaped sensor unit is formed in a touch mesh pattern. In addition, only the sensor unit may be formed in a touch mesh pattern, or a connection portion of the first touch electrode Tx and the second touch electrode Rx may also be formed in a touch mesh pattern.

The touch mesh pattern includes an outer line pattern and an inner line pattern. That is, the touch mesh pattern is defined as a structure including an outer line pattern forming an outer shell and an inner line pattern connecting the inside of the outer line pattern in a cross structure.

In the first touch electrode Tx and the second touch electrode Rx according to the first embodiment of the present invention, an outer line pattern is formed in a rhombus shape, and an inner line pattern like a mesh is formed therein. The inner line patterns are formed to cross each other while forming a network structure. The intersection angle and line width in the intersection area of the inner line pattern can be adjusted.

3 is a diagram illustrating a touch panel according to a second embodiment of the present invention.

Referring to FIG. 3 , a first touch electrode Tx and a second touch electrode Rx are formed on the transparent substrate 30 . In addition, a connection wire 20 connecting the first and second touch electrodes Tx and Rx to the pad electrode is formed. That is, the first touch electrode Tx and the second touch electrode Rx may receive a signal from an external device or externally apply a signal through the pad electrode and the connection wire 20 .

The substrate 30 is formed of a transparent material having excellent light transmittance, and may be formed of glass as an insulating substrate. In addition, in order to be applied to a flexible display device, it may be formed of a material having flexible characteristics, such as plastic or a metal thin film.

The first touch electrode Tx and the second touch electrode Rx may include a bar-shaped sensor unit. In the drawing, the first touch electrode Tx is formed by extending one electrode in one direction, and the second touch electrode Rx is formed in the form of a plurality of bars extending in the same direction as the first touch electrode Rx. , but is not limited thereto, and it is sufficient if the first touch electrode Tx and the second touch electrode Rx are formed in a bar shape. If we enlarge and examine area C in detail, it is as follows.

4 is a diagram illustrating a touch electrode according to a second embodiment of the present invention.

Referring to FIG. 4 , the first touch electrode Tx and the second touch electrode Rx include a bar-shaped sensor unit. The sensor portions of the first touch electrode Tx and the second touch electrode Rx are formed in a touch mesh pattern. The touch mesh pattern includes an outer line pattern and an inner line pattern. That is, the touch mesh pattern is defined as a structure including an outer line pattern forming an outer shell and an inner line pattern connecting the inside of the outer line pattern in a cross structure.

In the first touch electrode Tx and the second touch electrode Rx according to the second embodiment of the present invention, an outer line pattern is formed in a bar shape, and an inner line pattern like a mesh is formed therein. The inner line patterns are formed to cross each other while forming a network structure. The intersection angle and line width in the intersection area of the inner line pattern can be adjusted.

In addition, the shape of the touch electrode is not limited to the first and second embodiments, and may be formed in various ways according to the stacked structure of the touch panel. Depending on the laminated structure of the touch panel, there are Add-on method, Cover Glass integrated type, and Display integrated type. Add-on method includes GFF, GF2, GG, and Cover Glass integrated type such as G1F, G2.

GFF is the most common touch panel. It has a structure formed by laminating a PET film in which an Rx pattern for sensing X-axis coordinate values is laminated and a Tx pattern for sensing a Y-axis coordinate value by laminating two thin-film PET films on the underside of the cover glass. say GF2 refers to a structure formed by depositing thin films of Rx and Tx patterns on the upper and lower surfaces of PET film and stacking them on the bottom of the cover glass. GG refers to a structure formed by depositing a thin film of Rx pattern and Tx pattern on the top and bottom of a transparent substrate made of glass instead of ITO film and stacking it on the bottom of the cover glass.

Various structures may be applied to the touch panel according to the present invention, and the shape of the touch electrode may be formed in various ways according to the applied structure. In this case, the touch panel according to the present invention is characterized in that it includes a touch electrode including a touch mesh pattern. The touch mesh pattern includes an outer line pattern and an inner line pattern. The outer line pattern forms an outer portion of the touch electrode, and the inner line pattern is formed to form a network structure by connecting the inside of the outer line pattern in a cross structure.

The touch mesh pattern including the outer line pattern and the inner pattern line is formed by stacking nanowires and a coating layer. A detailed review of the one-unit pattern (B) of the touch mesh pattern of the touch electrode disclosed in FIGS. 2 and 4 is as follows.

5 is a diagram illustrating a plan view of a touch mesh pattern according to a third embodiment of the present invention. 6 is a cross-sectional view illustrating a touch mesh pattern according to a third embodiment of the present invention.

5 and 6 , a one-unit pattern B of the touch mesh pattern 100 of the touch electrode is disclosed. Although the one-unit pattern B is illustrated in a rhombus shape in the drawings, the present invention is not limited thereto. The one unit pattern (B) may be formed in various shapes such as circles, triangles, and polygons, and it is sufficient if a plurality of unit patterns (B) form a mesh pattern of a mesh structure.

The touch mesh pattern 100 includes a nanowire 101 and a coating layer 102 . The coating layer 102 is formed on the nanowire 101 . In this case, referring to FIG. 6 , the coating layer 102 may be a film formed on the substrate 30 and the nanowire 101 . In this case, the width of the coating layer 102 may be formed to be the same as the line width of the touch mesh pattern 100 .

The coating layer 102 may secure adhesion of the nanowire 101 and reduce contact resistance formed in the overlapping area of the nanowire 101 . When a plurality of nanowires are overlapped, contact resistance is generated in the overlapping region. That is, the overlapping nanowires are not recognized as a single material, but each nanowire is recognized as a single material, resulting in resistance in the overlapping region.

The coating layer 102 is also formed in the overlapping region of the nanowire 101 , so that the nanowire 101 is recognized as a single material, and contact resistance can be reduced. For this reason, the resistance can be further reduced compared to the touch electrode made of only the nanowire 101 . When the silver (Ag) nanowire is formed at 500 RPM, the resistance is 24 Ω/sq, and when the silver (Ag) nanowire and the GZO coating layer are laminated at 500 RPM, the resistance is 11 Ω/sq.

The coating layer 102 may be formed of silver (Ag) or a transparent conductive oxide (TCO). The transparent conductive film may be, for example, ITO, GZO, AZO, and FTO, but is not limited thereto.

The thickness of the coating layer 102 should be formed so that the transmittance is 80% or more. When the coating layer 102 is formed of silver (Ag), the coating layer 102 may be formed to a thickness of greater than 0 nm and less than or equal to 10 nm in consideration of transmittance. When the coating layer 102 is formed of a transparent conductive film, the coating layer 102 may be formed to a thickness of greater than 0 nm and less than or equal to 600 nm.

The nanowire 101 may be formed of silver (Ag) to form an electrode having high transmittance and low resistance. A plurality of silver nanowires 101 are networked and formed to be connected to each other like a mesh, and there is an advantage in that high electrical conductivity properties and transparency properties of 80 to 90% or more can be maintained.

In addition, when the touch mesh pattern is formed of a general metal, the metal mesh pattern formed in units of micrometers (㎛) has a problem in that a moire phenomenon occurs due to the total reflection characteristics of the metal. The touch electrode according to the present invention has the effect of improving the moire phenomenon by allowing the nanowire 101 to form a metal in nanometer (nm) units.

However, when the touch electrode is formed of the nanowire 101 , the nanowire electrode exhibits high haze characteristics. While such haze characteristics are high, there is a problem in that light scattering occurs on the curved surface of the nanowire, resulting in a milky phenomenon. The milky phenomenon is a phenomenon in which light is reflected from the curved surface of the nanowire and thus complete black is not achieved in a black state.

In the touch electrode according to the present invention, the one unit pattern (B) is formed so that the inside is opened to form the touch mesh pattern (100). As a result, reflection does not occur in the opening region, thereby reducing haze and improving the milky phenomenon. That is, the touch mesh pattern according to the present invention needs to secure a sufficient opening area to lower the haze to the level of the ITO electrode. In order to secure a sufficient opening area, the line width of the touch mesh pattern 100 may be formed to be 4 μm or more and 75 μm or less.

Conventional high-resistance ITO touch electrodes have a problem in that the RC delay time that is affected by the resistance (R) and the capacitance (C) occurs. When the touch electrode is formed of the touch mesh pattern 100 including the nanowire 101 , an electrode having a low resistance may be formed in comparison with the ITO touch electrode. In addition, since the touch electrode according to the present invention is formed of the touch mesh pattern 100 to form an opening region, capacitance can also be reduced. Therefore, the RC delay time of the touch panel according to the present invention can be formed to be 12% or less of the RC delay time when the touch electrode is formed with the ITO electrode.

7A to 7D are diagrams illustrating a method of manufacturing a touch mesh pattern according to a third embodiment of the present invention.

Referring to FIG. 7A , the nanowire 11 is formed on the substrate 30 . The nanowire 11 may be a silver (Ag) nanowire. The nanowire 11 may be formed of silver (Ag) to form an electrode having high transmittance and low resistance. A method of forming the nanowire 11 may be applied in various ways.

That is, in the present invention, the method of forming the nanowire 11 on the substrate 30 is not limited to a specific coating method such as an electrostatic spray coating method, a spin coating method, a general spray spray method, a screen printing method, an inkjet printing method, etc. No, any manufacturing method capable of forming a plurality of nanowires 11 to be networked and connected can be used.

In addition, it may be formed by coating an organic material layer including the nanowires 11 on the substrate 30 . The organic material layer is a dispersion solution of the nanowires 11, which helps the dispersibility of the nanowires 11 to be uniformly coated, and serves to secure the adhesion between the substrate 30 and the nanowires 11 after drying. do.

In addition to the nanowire 11 , the organic material layer may include a solvent formed of water, alcohols or volatile organic solvents, a dispersing agent and organic additives that increase the dispersibility of the nanowire 11 . The organic additive used in the organic layer is a transparent material, and a water-soluble material such as polyvinyl alcohol or a conductive polymer such as PEDOT and polyaniline may be used. In addition, the organic material layer may be formed in a water-soluble solution to further lower the resistance, and then removed with an aqueous solution after the drying process is completed.

Referring to FIG. 7B , the coating layer 12 is formed on the substrate 30 on which the nanowire 11 is formed. The coating layer 12 may secure adhesion of the nanowire 101 and reduce contact resistance formed in the overlapping area of the nanowire 11 .

The overlapping nanowires are not recognized as a single material, but each nanowire is recognized as a single material, resulting in resistance in the overlapping region. The coating layer 12 is formed on the overlapping region of the nanowires 11 so that the overlapping nanowires 11 are recognized as one material, and contact resistance can be reduced. For this reason, the resistance can be further reduced compared to the touch electrode made of only nanowires.

The coating layer 12 may be formed of silver (Ag) or a transparent conductive oxide (TCO). The transparent conductive film may be, for example, ITO, GZO, AZO, and FTO, but is not limited thereto.

The thickness of the coating layer 12 should be formed so that the light transmittance is 80% or more. When the coating layer 12 is formed of silver (Ag), the coating layer 12 may be formed to a thickness of greater than 0 nm and less than or equal to 10 nm in consideration of transmittance. When the coating layer 12 is formed of a transparent conductive film, the coating layer 12 may be formed to a thickness of greater than 0 nm and less than or equal to 600 nm.

A method of forming the coating layer 12 may be formed by various deposition methods. Preferably, it may be formed by sputtering. However, the method of forming the coating layer 12 is not limited thereto, and it is sufficient if the coating layer 12 can be formed to an appropriate thickness.

Referring to FIG. 7C , a photoresist layer is formed on the substrate 30 on which the nanowire 11 and the coating layer 12 are formed. The photoresist layer may be formed of a negative photoresist, which is a photosensitive material that is a material that is cured when irradiated with light. However, the process may be performed using a positive photoresist, which is a material that softens when irradiated with light.

A mask including a blocking part and a transmissive part is placed on the photoresist layer, and the transmissive part of the mask is irradiated with light in a region where the touch electrode is formed. Thereafter, when the development process is performed, the photoresist pattern 13 is formed only on the area where the touch electrode is to be formed on the coating layer 12 .

Although the drawing shows that only one unit pattern of the touch mesh pattern of the touch electrode is formed to form the photoresist pattern 13 , the photoresist pattern 13 may be formed in all areas that become the touch electrode. That is, the photoresist pattern 13 shown in the drawing may be further extended and formed in the entire region corresponding to the touch mesh pattern, and further may be formed in the entire region corresponding to the touch electrode.

In addition, although the photoresist pattern 13 is illustrated so that the unit pattern has a rhombus shape in the drawings, the present invention is not limited thereto. The one unit pattern may be formed in various shapes such as circles, triangles, and polygons, and it is sufficient if a plurality of unit patterns form a mesh pattern of a mesh structure. Accordingly, the photoresist pattern 13 may also be formed in various shapes such as circles, triangles, and polygons, and it is sufficient if a plurality of unit patterns form a mesh pattern of a mesh structure.

Referring to FIG. 7D , the nanowire and the coating layer are etched using the photoresist pattern (see FIG. 7C , 13 ) as a mask, and the photoresist pattern is peeled off, thereby making a touch including the nanowire 101 and the coating layer 102 . A touch electrode including the mesh pattern 100 is formed.

At this time, in the step of forming the coating layer (see FIG. 7b , 12 ), since the coating layer 12 was formed on the entire surface of the substrate 20 , when etching the pattern formed on the coating layer 12 as a mask, touch The width of the coating layer 102 of the mesh pattern 100 may be formed to be the same as the line width of the touch mesh pattern 100 .

The etching may be performed by wet etching using the photoresist pattern as a mask. However, the present invention is not limited thereto, and dry etching may be used. In addition, although the etching process using the photoresist process is disclosed in FIG. 7C , the touch electrode including the touch mesh pattern 100 made of the nanowire 101 and the coating layer 102 through laser etching is not limited thereto. can be formed

When the touch mesh pattern is formed of a general metal, the metal mesh pattern formed in micrometers (㎛) has a problem in that a moire phenomenon occurs due to the total reflection characteristics of the metal. The touch electrode according to the present invention has the effect of improving the moire phenomenon by allowing the nanowire 101 to form a metal in nanometer (nm) units.

However, when the touch electrode is formed of the nanowire 101 , the nanowire electrode exhibits a high haze characteristic, and there is a problem in that a milky phenomenon occurs. Accordingly, the touch electrode according to the present invention is formed as a touch mesh pattern 100 in which one unit pattern is opened. As a result, reflection does not occur in the opening region, thereby reducing haze and improving the milky phenomenon.

That is, the touch mesh pattern according to the present invention needs to secure a sufficient opening area to lower the haze to the level of the ITO electrode. In order to secure a sufficient opening area, the line width of the touch mesh pattern 100 may be formed to be 4 μm or more and 75 μm or less. In addition, the photoresist pattern 13 of FIG. 7C is formed in consideration of the line width of the touch mesh pattern 100 .

8 is a diagram illustrating a plan view of a touch mesh pattern according to a fourth embodiment of the present invention. 9 is a diagram illustrating a cross-sectional view of a touch mesh pattern according to a fourth embodiment of the present invention. The description overlapping with the third embodiment of the present invention may be omitted.

Referring to FIGS. 8 and 9 , a one-unit pattern B of the touch mesh pattern 200 of the touch electrode is disclosed. Although the one-unit pattern B is illustrated in a rhombus shape in the drawings, the present invention is not limited thereto. The one unit pattern (B) may be formed in various shapes such as circles, triangles, and polygons, and it is sufficient if a plurality of unit patterns (B) form a mesh pattern of a mesh structure.

The touch mesh pattern 200 includes a nanowire 201 and a coating layer 202 . The coating layer 202 is formed on the nanowire 201 . In this case, referring to FIG. 9 , the coating layer 202 surrounds the nanowire 201 and may be formed only in a region in contact with the nanowire 201 .

The coating layer 202 may secure adhesion of the nanowire 201 and reduce contact resistance formed in the overlapping area of the nanowire 201 . The coating layer 202 is also formed in the overlapping region of the nanowires 201 , so that the nanowires 201 are recognized as a single material and contact resistance can be reduced. That is, the resistance can be further reduced as compared with the touch electrode made of only the nanowire 201 .

In addition, the coating layer 202 surrounds the nanowire 201 and is formed only in a region in contact with the nanowire 201 , so that the region between the nanowires 201 is opened. For this reason, the transmittance|permeability of a touch panel can be improved more.

The coating layer 202 is formed of a material that can be plated by using the nanowire 201 as a seed. Preferably, it may be formed of silver (Ag) or copper (Cu).

The nanowire 201 may be formed of silver (Ag) to form an electrode having high transmittance and low resistance. A plurality of silver nanowires 201 are networked and formed to be connected to each other like a mesh, and there is an advantage in that high electrical conductivity properties and transparency properties of 80 to 90% or more can be maintained.

In addition, when the touch mesh pattern is formed of a general metal, the metal mesh pattern formed in units of micrometers (㎛) has a problem in that a moire phenomenon occurs due to the total reflection characteristics of the metal. The touch electrode according to the present invention has the effect of improving the moire phenomenon by allowing the nanowire 101 to form a metal in nanometer (nm) units.

In addition, in the touch electrode according to the present invention, the one unit pattern (B) is formed so that the inside is opened to form the touch mesh pattern (200). As a result, reflection does not occur in the opening region, thereby reducing haze and improving the milky phenomenon. In order to secure a sufficient opening area, the line width of the touch mesh pattern 200 may be formed to be 4 μm or more and 75 μm or less.

A low resistance electrode may be formed by forming a touch electrode using the touch mesh pattern 200 including the nanowire 201 . In addition, since the opening region is formed, the capacitance can also be reduced. For this reason, it is possible to reduce the RC delay time of the touch panel according to the present invention.

10A and 10B are diagrams illustrating a method of manufacturing a touch mesh pattern according to a fourth embodiment of the present invention. A description overlapping with the third embodiment may be omitted.

Referring to FIG. 10A , a nanowire 21 is formed on a substrate 30 , and a coating layer 22 is formed on the nanowire 21 . The nanowire 21 may be a metal, preferably silver (Ag) nanowire. The nanowire 21 may be formed of silver (Ag) to form an electrode having high transmittance and low resistance. A method of forming the nanowire 21 may be applied in various ways.

That is, in the present invention, the method of forming the nanowire 11 on the substrate 30 is not limited to a specific coating method such as an electrostatic spray coating method, a spin coating method, a general spray spray method, a screen printing method, an inkjet printing method, etc. No, any manufacturing method capable of forming a plurality of nanowires 11 to be networked and connected can be used.

The coating layer 22 may be formed only on the nanowire 21 using a plating process. In the plating process, silver (Ag) or copper (Cu) is grown by using the nanowire 21 as a seed to form the coating layer 22 . That is, the coating layer 22 may be preferably formed of silver (Ag) or copper (Cu). However, the present invention is not limited thereto, and any material capable of plating using the nanowire 21 as a seed is sufficient.

The coating layer 22 formed by the plating process surrounds the nanowire 21 and may be formed only in a region in contact with the nanowire 21 . In addition, the coating layer 22 surrounds the nanowire 21 and is formed only in a region in contact with the nanowire 21 , so that the region between the nanowires 21 is opened. For this reason, the transmittance|permeability of a touch panel can be improved more.

The coating layer 22 may secure the adhesion of the nanowires 21 . In addition, contact resistance formed in the overlapping region of the nanowire 21 may be reduced. The coating layer 22 is also formed in the overlapping region of the nanowires 21 , so that the nanowires 21 are recognized as a single material and contact resistance can be reduced. That is, the resistance can be further reduced as compared with the touch electrode made of only the nanowire 21 .

Referring to FIG. 10B , the nanowire and the coating layer may be etched to form the touch mesh pattern 200 including the nanowire 201 and the coating layer 202 . Although only one unit pattern of the touch mesh pattern 200 of the touch electrode is illustrated in the drawings, a plurality of the one unit patterns are formed to form a touch mesh pattern and further to form a touch electrode.

Also, in the drawings, the one-unit pattern is illustrated in a rhombus shape, but the present invention is not limited thereto. The one unit pattern may be formed in various shapes such as circles, triangles, and polygons, and it is sufficient if a plurality of unit patterns form a mesh pattern of a mesh structure.

The process of etching the nanowires and the coating layer may be performed by wet etching or dry etching using a photoresist process, or laser etching. In the case of the photoresist process, a photoresist pattern may be formed in consideration of the line width of the touch mesh pattern 200 .

When the touch mesh pattern is formed of a general metal, the metal mesh pattern formed in micrometers (㎛) has a problem in that a moire phenomenon occurs due to the total reflection characteristics of the metal. The touch electrode according to the present invention has the effect of improving the moire phenomenon by allowing the nanowire 201 to form a metal in nanometer (nm) units.

However, when the touch electrode is formed of the nanowire 201 , the nanowire electrode exhibits a high haze characteristic, and there is a problem in that a milky phenomenon occurs. Accordingly, the touch electrode according to the present invention is formed as a touch mesh pattern 200 in which one unit pattern is opened. As a result, reflection does not occur in the opening region, thereby reducing haze and improving the milky phenomenon.

That is, the touch mesh pattern according to the present invention needs to secure a sufficient opening area to lower the haze to the level of the ITO electrode. In order to secure a sufficient opening area, the line width of the touch mesh pattern 200 may be formed to be 4 μm or more and 75 μm or less.

Therefore, the touch panel and its manufacturing method according to the present invention have low resistance, no RC delay time, no pattern recognized by the naked eye, and can be applied to a large area. In addition, the moire phenomenon is improved by using nanowires, the milky phenomenon is improved by forming a mesh pattern, and a coating layer is formed on the nanowires to reduce the resistance generated in the nanowire overlapping area, and improve the adhesion of the nanowires. can do it Such a touch panel and a method for manufacturing the same can be applied to a flexible display device.

Those skilled in the art from the above description will be able to see that various changes and modifications can be made without departing from the technical spirit of the present invention. Accordingly, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

30: substrate
100,200: touch mesh pattern
101,201: nanowire
102,202: coating layer

Claims (20)

A touch electrode comprising a sensor unit having a mesh pattern on a substrate and a connection unit connecting the sensor unit,
The mesh pattern is composed of a plurality of unit patterns,
The mesh pattern has an interior opening in one unit pattern, and includes a plurality of nanowires and a coating layer formed on the plurality of nanowires including spaces between the plurality of nanowires, the touch panel.
The method of claim 1,
The mesh pattern may include: an outer line pattern constituting an outer part; and
A structure including an inner line pattern connecting the inside of the outer line pattern in a cross structure, and the touch panel including the plurality of unit patterns.
The method of claim 1,
The sensor unit is a touch panel made of one shape selected from the group consisting of a rhombus, a circle, and a triangle.
The method of claim 1,
The coating layer is in the form of a film covering the mesh pattern on the substrate and the nanowire, and the width of the coating layer and the width of the sensor unit are the same.
5. The method of claim 4,
The coating layer is a touch panel composed of silver (Ag) or a transparent conductive oxide (TCO).
5. The method of claim 4,
The coating layer is a touch panel composed of a thickness having a light transmittance of 80% or more.
The method of claim 1, wherein the touch electrode comprises:
a first touch electrode configured by extending one electrode in one direction; and
A touch panel including a second touch electrode configured in the form of a plurality of bars extending in the one direction.
The method of claim 1,
The plurality of nanowires overlap each other in the single unit pattern, and the coating layer is also formed in an area where the plurality of nanowires overlap.
The method of claim 1,
The line width of the mesh pattern is 4㎛ or more and 75㎛ or less of the touch panel.
The method of claim 1,
The nanowire is a touch panel comprising a silver (Ag) nanowire.
forming a plurality of nanowires on a substrate;
forming a coating layer on the plurality of nanowires; and
etching the plurality of nanowires and the coating layer to form a mesh pattern to form a touch electrode,
The mesh pattern is composed of a plurality of unit patterns,
The mesh pattern has an interior opening in one unit pattern, and is formed of a coating layer formed on the plurality of nanowires including the plurality of nanowires and a space between the plurality of nanowires.
12. The method of claim 11,
The coating layer is a method of manufacturing a touch panel to form a sputtering (sputtering) process.
delete 13. The method of claim 12,
The method of manufacturing a touch panel in which the coating layer is formed of silver (Ag) or a transparent conductive oxide (TCO).
13. The method of claim 12,
The method of manufacturing a touch panel in which the coating layer is formed to a thickness having a light transmittance of 80% or more.
12. The method of claim 11,
The method of manufacturing a touch panel in which the coating layer is formed by a plating process using the nanowire as a seed.
12. The method of claim 11,
The touch electrode is
a first touch electrode configured by extending one electrode in one direction; and
A method of manufacturing a touch panel including a second touch electrode configured in the form of a plurality of bars extending in the one direction.
12. The method of claim 11,
The plurality of nanowires overlap each other in the single unit pattern, and the coating layer is also formed in an area where the plurality of nanowires overlap.
12. The method of claim 11,
A method of manufacturing a touch panel in which the line width of the mesh pattern is 4 μm or more and 75 μm or less.
12. The method of claim 11,
The nanowire is a method of manufacturing a touch panel including a silver (Ag) nanowire.

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