JP2010231299A - Touch panel, method for manufacturing he same, method for manufacturing display device, and method for manufacturing electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To maintain quality and suppress decrease of yield even when using a printing method. <P>SOLUTION: A touch panel includes a plurality of first electrodes 10 and a plurality of second electrodes 20 which are formed on one side of a substrate 1 and extend in the direction crossing each other. A method for manufacturing the touch panel includes: an electrode film forming process to form the plurality of first electrodes and an electrode film of a shape to segment and space the second electrode at the intersection K to the first electrode on the substrate; an insulating film forming process to form an insulating film 30 at the first electrode of the intersection at least using the printing method; and a bridge wire forming process to form a bridge wire 21 for connecting the second electrodes spaced at the intersection via the insulating film using the printing method. The insulating film forming process includes: a first process to form an insulating film body 31 on the first electrodes at least; and a second process to fill in a recessed portion 31b generated on the surface 31a of the insulating film body formed in the first process and to flatten the surface. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a touch panel, a manufacturing method thereof, a display device manufacturing method, and an electronic device manufacturing method.

  A capacitive touch screen has a capacitance formed between the electrodes of the panel by bringing a finger or the like close to a predetermined position of the panel on which the electrodes are formed, and a current for charging the capacitance thus formed. By detecting, a predetermined position is detected. For example, the following are disclosed as capacitive touch screens.

  The coordinate input device described in Patent Document 1 has a configuration in which a liquid crystal layer is sandwiched between a substrate provided with an X electrode and a substrate provided with a Y electrode. The detection pen electrode close to the substrate on the X electrode side forms a stray capacitance between the X electrode and the Y electrode, and the position of the detection pen is detected by the voltage induced when the stray capacitance is charged. (See Patent Document 1).

  Next, in the information input / output device described in Patent Document 2, electrodes arranged in a matrix corresponding to the respective pixels of the display portion and active elements provided for the respective electrodes are formed on the same substrate. Is formed. These electrodes function as sensing electrodes for position detection (see Patent Document 2).

  Next, the coordinate input device described in Patent Document 3 has a configuration in which X electrodes and Y electrodes that intersect with each other are formed on the front surface and the back surface of the sensor substrate, respectively. Then, the position is detected by a change in current accompanying a change in the lines of electric force from the X electrode to the Y electrode with a finger approaching from the X electrode side (see Patent Document 3).

  Next, the coordinate position input device described in Patent Document 4 has a configuration in which a plurality of electrodes that are arranged to face each other via an insulating layer and intersect each other are provided. Then, position detection is performed by detecting a current changed by an operator's finger approaching the electrode (see Patent Document 4).

JP-A-4-337824 JP-A-6-318136 JP-A-9-305289 Japanese Patent Laid-Open No. 10-63403

NATURE, 389, 1997, p.827

However, the following problems exist in the conventional technology as described above.
In the inventions described in these Patent Documents 1 to 4, when an electrode extending in each direction or an electrode and an active circuit are formed on the same substrate, a sputtering method, a photolithography method, an etching method, etc. Since the wiring layer is laminated by repeating the above several times, there is a problem that the manufacturing cost increases.
Therefore, it is conceivable to form an active circuit by arranging the electrodes and the insulating film on the substrate using, for example, a printing method. For example, as a method of forming an insulating film in a rectangular shape at the intersection of the X electrode and the Y electrode, the manufacturing cost is greatly increased by using the method of ejecting the insulating film forming ink from the fluid ejecting apparatus and forming the insulating film. It becomes possible to suppress. However, it is difficult to form a flat insulating film having a uniform thickness by a method in which a droplet including a material for forming an insulating film is discharged onto the surface of the substrate to form the insulating film on the surface of the substrate. In other words, when a film is formed by landing a droplet for forming an insulating film on a predetermined region of a flat substrate surface, a uniform thickness is obtained in the state of the liquid film for forming an insulating film formed by the landed droplet. Even when the liquid medium evaporates from the liquid film and dries, the insulating film material, which is the solute dissolved in the liquid medium, accumulates on the periphery of the formed film. As a result, there is a problem that the film thickness of the peripheral portion of the insulating film becomes thicker than other portions, and a flat insulating film is not formed.
This is a phenomenon called “coffee ring” or “coffee stain”, and is a phenomenon that occurs when a droplet in which a solute is dissolved in a liquid medium is dried. That is, the amount of evaporation at the outer edge of the liquid film spread on the substrate, that is, the peripheral edge, is larger than that at other parts, so that the liquid flows toward the peripheral edge to compensate for it, and as a result, the peripheral edge rises after drying. This is a phenomenon in which a thick film is formed (see Non-Patent Document 1, for example).
When a bridge wiring that connects the other electrode is formed on the surface of the insulating film having large unevenness on the surface, the bridge wiring is bent and thinned at the convex portion, which may cause disconnection. In particular, when a wiring forming liquid material is used to form wiring, it is easily affected by surface irregularities, and the wiring forming liquid material arranged at the position of the convex portion flows into the concave portion. It becomes difficult to control the thickness and width of the wiring. As a result, the bridge wiring formed on the surface of the insulating film having large irregularities is likely to have non-uniform thickness, and the resistance value is not constant, so that the quality stability is difficult.

  The present invention has been made in consideration of the above points. A touch panel manufacturing method, a display device manufacturing method, and an electronic device manufacturing method that can maintain quality and suppress a decrease in yield even when a printing method is used. The purpose is to provide.

In order to achieve the above object, the present invention employs the following configuration.
A method for manufacturing a touch panel according to the present invention is a method for manufacturing a touch panel that is formed on one side of a substrate and has a plurality of first electrodes and a plurality of second electrodes that extend in directions intersecting each other. An electrode film forming step of forming a plurality of the first electrodes and an electrode film having a shape separated from and separated from the second electrode at the intersection with the first electrode, and at least the first at the intersection An insulating film forming step of forming an insulating film on the electrode by using a printing method and a bridge wiring that connects the second electrode spaced apart at the intersection via the insulating film is printed. A bridge wiring forming step formed by using the insulating film forming step, wherein the insulating film forming step includes at least a first step of forming an insulating film main body on the first electrode and the insulating film main body formed in the first step. The surface of the surface is filled with a recess formed on the surface. It is characterized in that a second step of flattening.
Therefore, in the touch panel manufacturing method of the present invention, the first electrode and the electrode film to be the second electrode are formed in the same process, and the bridge wiring for connecting the electrode films is formed by a printing method. Since the man-hours for forming the first and second electrodes can be reduced, it is possible to provide a method for manufacturing a touch panel with reduced manufacturing costs.
Further, in the present invention, even when a recess is formed by bleeding when the insulating film body is formed, the recess is filled in the second step and the surface is flattened, so that the step can be reduced. Therefore, in the present invention, it is possible to reduce the amount of bending of the bridge wiring and suppress the occurrence of disconnection.

Moreover, in this invention, the procedure which fills the said recessed part with the material used when forming the said insulating film main body can also be employ | adopted suitably.
Thereby, in this invention, while it becomes unnecessary to prepare the material which fills a recessed part separately, it becomes possible to implement a 2nd process following a 1st process, and it can contribute to reduction of manufacturing cost and improvement of manufacturing efficiency.

Moreover, in this invention, the procedure which fills the said recessed part with the material used when forming the said bridge | bridging wiring can also be employ | adopted suitably.
Accordingly, in the present invention, it is not necessary to separately prepare a material for filling the concave portion, and it is possible to perform a bridge wiring forming step following the second step, which can contribute to reduction in manufacturing cost and improvement in manufacturing efficiency. .

And the display apparatus manufacturing method of this invention has the process of manufacturing a touch panel by the manufacturing method as described previously.
Therefore, in the display device manufacturing method of the present invention, it is possible to obtain a high-quality display device in which an increase in material cost is prevented and an increase in resistance value, occurrence of disconnection, and the like are suppressed.

Moreover, the electronic device manufacturing method of the present invention is characterized by including a step of manufacturing a display device by the manufacturing method described above.
Therefore, in the electronic device manufacturing method of the present invention, it is possible to obtain a high-quality electronic device in which an increase in material cost is prevented, and occurrence of problems due to an increase in resistance value, disconnection, or the like is suppressed.

On the other hand, the touch panel of the present invention is a touch panel that is formed on one surface side of a substrate and has a plurality of first electrodes and a plurality of second electrodes that extend in directions crossing each other, and the first electrode on the substrate. Between the second electrode separated and separated at the intersection with the first electrode, at least the insulating film formed on the first electrode at the intersection, and the second electrode separated at the intersection. Bridge wiring connected via the film, and the insulating film includes an insulating film main body and a flattening portion that is embedded in a recess formed on the surface of the insulating film main body and flattens the surface. It is characterized by having.
Therefore, in the touch panel of the present invention, even when the concave portion is formed by spreading when the insulating film body is formed, the step can be reduced because the concave portion is filled and the surface is flattened in the second step. Therefore, in the present invention, it is possible to reduce the amount of bending of the bridge wiring and suppress the occurrence of disconnection.

As the flattening portion, a structure formed of the same material as the insulating film main body can be suitably employed.
Accordingly, in the present invention, it is not necessary to separately prepare a material for filling the concave portion, and it is possible to continuously manufacture the insulating film and the flattened portion, which can contribute to reduction in manufacturing cost and improvement in manufacturing efficiency. .

As the flattening portion, a configuration formed of the same material as that of the bridge wiring can be suitably employed.
Accordingly, in the present invention, it is not necessary to separately prepare a material for filling the concave portion, and it becomes possible to continuously manufacture the flattened portion and the bridge wiring, which can contribute to reduction of manufacturing cost and improvement of manufacturing efficiency. .

2 is a schematic plan view of a touch panel 100. FIG. 2 is a schematic cross-sectional view of a touch panel 100. FIG. It is a schematic cross section of touch panel 100A. It is a flowchart figure which concerns on the manufacturing method of a touch panel. It is a perspective view which shows schematic structure of the droplet discharge apparatus IJ. It is a figure for demonstrating the discharge principle of a liquid material. 5 is a manufacturing process diagram of the touch panel 100. FIG. 5 is a manufacturing process diagram of the touch panel 100. FIG. 5 is a manufacturing process diagram of the touch panel 100. FIG. FIG. 2 is a schematic plan view and a schematic cross-sectional view of a liquid crystal display device 500. It is a perspective view which shows an example of the electronic device which concerns on this invention.

Hereinafter, embodiments of a touch panel, a manufacturing method thereof, a display device manufacturing method, and an electronic device manufacturing method according to the present invention will be described with reference to FIGS.
The following embodiment shows one aspect of the present invention and does not limit the present invention, and can be arbitrarily changed within the scope of the technical idea of the present invention. Moreover, in the following drawings, in order to make each configuration easy to understand, the actual structure is different from the scale and number of each structure.

<First Embodiment>
[Touch panel]
FIG. 1 is a schematic plan view of a touch panel 100 according to the present embodiment. FIG. 2 is a schematic cross-sectional view of the touch panel 100 taken along the line AA ′.

The touch panel 100 includes a substrate 1, an input area 2, and a lead wiring 60.
The substrate 1 is formed in a rectangular shape in plan view, and a transparent material such as glass or acrylic resin is used as the material thereof.

The input area 2 is an area surrounded by an alternate long and short dash line in FIG. 1 and is an area for detecting position information of a finger input to the touch panel.
In the input region 2, a plurality of X electrodes (first electrodes) 10 and a plurality of Y electrodes (second electrodes) 20 are respectively arranged.
The X electrode 10 extends in the X-axis direction in the figure, and a plurality of X electrodes 10 are arranged at intervals in the Y-axis direction. The Y electrodes 20 extend in the Y-axis direction in the figure, and the Y electrodes 20 are arranged at intervals from each other in the X-axis direction. The X electrode 10 and the Y electrode 20 intersect at the intersection K in the input region 2 by intersecting each other's bridge wiring.

  The X electrode 10 includes a plurality of island-shaped electrode portions 12 arranged in the X-axis direction and a bridge wiring 11 that connects adjacent island-shaped electrode portions 12 to each other. The island-shaped electrode portion 12 is formed in a rectangular shape in plan view, and is arranged so that one diagonal line is along the X axis.

The Y electrode 20 includes a plurality of island electrode portions 22 arranged in the Y-axis direction, and a bridge wiring 21 that connects the adjacent island electrode portions 22 to each other.
The island-shaped electrode part 22 is formed in a rectangular shape in plan view, and is arranged so that one diagonal line is along the Y axis.
The island-like electrode portions 12 and the island-like electrode portions 22 are alternately arranged (checkered arrangement) in the X-axis direction and the Y-axis direction. In the input region 2, the rectangular island-like electrode portions 12 and 22 are arranged. They are arranged in a matrix in plan view.

  As a material constituting the X electrode 10 and the Y electrode 20, a light-transmitting resistor such as ITO (indium tin oxide), IZO (indium zinc oxide; registered trademark), ZnO, or the like can be used.

  The routing wiring 60 is connected to the X electrode 10 and the Y electrode 20, and is connected to a driving unit and an electric signal conversion / calculation unit (both not shown) provided in the touch panel 100 or in an external device. .

Next, the sectional view of FIG. 2 will be described.
On the functional surface 1 a of the substrate 1, island-shaped electrode portions 12 (not shown), island-shaped electrode portions 22, and bridge wirings 11 are provided. An insulating film 30 is formed on the bridge wiring 11. A bridge wiring 21 is disposed along the surface of the insulating film 30.
In addition, the routing wiring 60 is disposed on the functional surface 1 a of the substrate 1. The routing wiring 60 includes a first layer 60a disposed on the functional surface 1a and a second layer 60b stacked on the first layer 60a. A wiring protective film 62 is formed so as to cover the routing wiring 60.

  A planarizing film 40 is formed so as to cover these electrodes and wiring. A protective substrate 50 is disposed on the planarizing film 40 via an adhesive layer 51. A shield layer 70 is provided on the back surface 1 b of the substrate 1.

The insulating film 30 insulates the bridge wiring 11 and the bridge wiring 21 that intersect three-dimensionally, and is formed in a rectangular shape in plan view as shown in FIGS.
The insulating film 30 includes an insulating film main body 31 and a flattening portion 32 that is embedded in a recess formed on the surface 31a of the insulating film main body 31 and flattens the surface 31a. In the present embodiment, the planarizing portion 32 is formed of the same material as the insulating film main body 31.

The insulating film 30 (insulating film body 31) can be formed by applying polysiloxane, an acrylic resin, an acrylic monomer, or the like using a printing method, and drying and solidifying it.
When formed using polysiloxane, the insulating film 30 is an inorganic insulating film made of silicon oxide. On the other hand, when an acrylic resin and an acrylic monomer are employed, the insulating film 30 is an organic insulating film made of a resin material. Here, as an example, an ink in which JSR NN525E and EDM (diethylene glycol ethyl methyl ether) are mixed at a ratio of 4: 1 (weight ratio) is used.

As a constituent material of the insulating film 30, it is preferable to employ a material having a relative dielectric constant of 4.0 or less, desirably 3.5 or less. Thereby, the parasitic capacitance in the intersection part of bridge wiring can be reduced, and the position detection performance of a touch panel can be hold | maintained.
The constituent material of the insulating film 30 is preferably a material having a refractive index of 2.0 or less, preferably 1.7 or less. Thereby, the refractive index difference with the board | substrate 1, X electrode 10, and Y electrode 20 can be made small, and it can prevent that the pattern of the insulating film 30 is visible to a user.

The first layer 60a of the routing wiring 60 is obtained by extending the X electrode 10 or the Y electrode 20 to a region outside the input region 2, and is formed by a resistor such as ITO or IZO.
The second layer 60b is laminated on the first layer 60a, and reduces the wiring resistance of the routing wiring 60. The second layer 60b is made of an organic compound, nanoparticle, nanowire, or the like containing one or more of metals such as Au, Ag, Al, Cu, and Pd, and carbon (nanocarbon such as graphite and carbon nanotube). Can be used. The constituent material of the second layer 60b is not particularly limited as long as the sheet resistance can be made smaller than that of the first layer 60a.

  Similar to the insulating film 30, the wiring protective film 62 covering the routing wiring 60 can be formed by a printing method using polysiloxane, acrylic resin, acrylic monomer, or the like as a forming material. Therefore, the wiring protective film 62 can be formed at the same time in the process of forming the insulating film 30.

The planarizing film 40 is formed so as to cover at least the input region 2 of the functional surface 1 a of the substrate 1, and planarizes the unevenness of the functional surface 1 a due to the X electrode 10 and the Y electrode 20. As shown in the drawing, the planarizing film 40 is preferably formed so as to cover substantially the entire functional surface 1a (excluding the external connection terminal portion). Since the functional surface 1a side of the substrate 1 is planarized by the planarizing film 40, the substrate 1 and the protective substrate 50 can be bonded uniformly over almost the entire surface.
Further, as the constituent material of the planarizing film 40, a material having a refractive index of 2.0 or less, desirably 1.7 or less is preferably used. Thereby, the refractive index difference with the board | substrate 1, X electrode 10, and Y electrode 20 can be made small, and the wiring pattern of X electrode 10 or Y electrode 20 can be made difficult to see.

  The protective substrate 50 is a transparent substrate such as glass or plastic. Or when the touch panel 100 of this embodiment is arrange | positioned in front of display apparatuses, such as a liquid crystal panel and an organic electroluminescent panel, as the protective substrate 50, an optical element substrate (polarizing plate or position) used as a part of a display apparatus. A phase difference plate or the like can also be used.

The shield layer 70 is formed by depositing a transparent conductive material such as ITO or IZO (registered trademark) on the back surface 1 b of the substrate 1. Or it is good also as a structure which prepared the film in which the transparent conductive film used as a shield layer was formed, and adhere | attached this film on the back surface 1b of the board | substrate 1. FIG.
By providing the shield layer 70, the electric field is blocked on the back surface 1 b side of the substrate 1. Thereby, it is possible to prevent the electric field of the touch panel 100 from acting on the display device or the like, or the electric field of an external device such as the display device from acting on the touch panel 100.

In the present embodiment, the shield layer 70 is formed on the back surface 1b of the substrate 1. However, the shield layer may be formed on the functional surface 1a side of the substrate 1 as shown in FIG. FIG. 3 is a schematic cross-sectional view showing a touch panel 100A of such a modification.
In the touch panel 100A shown in FIG. 3, a shield layer 70A is formed on the functional surface 1a of the substrate 1, and an insulating film 80A is formed to cover the shield layer 70A. The configuration on the insulating film 80A is the same as that of the touch panel 100 shown in FIG. In the touch panel 100A, since the shield layer 70A, the X electrode 10, the Y electrode 20, the routing wiring 60, and the like are formed on one surface of the substrate 1, the manufacturing process can be prevented from becoming complicated, and the touch panel has excellent manufacturability. be able to.

Here, the operation principle of the touch panel 100 will be briefly described.
First, a predetermined potential is supplied to the X electrode 10 and the Y electrode 20 from the driving unit (not shown) via the routing wiring 60.
For example, a ground potential (ground potential) is input to the shield layer 70.

  When a finger is brought closer to the input area 2 from the protective substrate 50 side in the state where the potential is supplied as described above, each of the finger brought close to the protective substrate 50 and each of the X electrode 10 and the Y electrode 20 in the vicinity of the approach position. Parasitic capacitance is formed between Then, in the X electrode 10 and the Y electrode 20 in which the parasitic capacitance is formed, a temporary potential drop is caused in order to charge the parasitic capacitance.

The drive unit senses the potential of each electrode, and immediately detects the X electrode 10 and the Y electrode 20 in which the above-described potential drop has occurred. Then, the position information of the finger in the input area 2 is detected by analyzing the detected electrode position by the electric signal conversion / calculation unit.
Specifically, the Y coordinate in the input area 2 at the position where the finger approaches is detected by the X electrode 10 extending in the X axis direction, and the X electrode in the input area 2 is detected by the Y electrode 20 extending in the Y axis direction. Coordinates are detected.

[Method for manufacturing touch panel]
Next, the manufacturing method of said touch panel is demonstrated.
In the present embodiment, a method for manufacturing the touch panel 100 shown in FIGS. 1 and 2 will be described with reference to the drawings. FIG. 4 is a flowchart according to the touch panel manufacturing method.

  As shown in FIG. 4, the manufacturing process of the touch panel of this embodiment includes electrodes that form island-like electrode portions 12 and 22, bridge wiring 11, and first layer 60 a of routing wiring 60 on the functional surface 1 a of the substrate 1. A film forming step S10, an auxiliary wiring forming step S20 in which the second layer 60b is laminated on the first layer 60a of the routing wiring 60, an insulating film 30 is formed on the bridge wiring 11, and the routing wiring 60 is covered to protect the wiring. An insulating film forming step S30 for forming the film 62, a bridge wiring forming step S40 for forming the bridge wiring 21 for connecting the adjacent island electrode portions 22 via the insulating film 30, and a functional surface of the substrate 1 A flattening film forming step (protective film forming step) S50 for forming a flattening film 40 for flattening the 1a side, and protective substrate bonding for bonding the protective substrate 50 to the flattening film 40 via an adhesive layer 51 Extent and (adhesive layer forming step) S60, and a shield layer forming step (conductive film forming step) S70 of forming the shielding layer 70 on the back surface 1b of the substrate 1.

  The manufacturing process of the touch panel 100 of this embodiment includes a process of forming a film by a droplet discharge method which is a kind of printing method. Therefore, prior to the description of the touch panel manufacturing method, the droplet discharge device will be described.

  FIG. 5 is a perspective view showing a schematic configuration of the droplet discharge device IJ. The droplet discharge device IJ includes a droplet discharge head 1001, an X-axis direction drive shaft 1004, a Y-axis direction guide shaft 1005, a control device CONT, a stage 1007, a cleaning mechanism 1008, a base 1009, and a heater. 1015. An electromechanical conversion type droplet discharge device using a piezo element (piezoelectric element) is used as an apparatus for performing this.

  The stage 1007 supports the substrate P on which a liquid material (wiring pattern ink) is placed by the droplet discharge device IJ, and includes a fixing mechanism (not shown) that fixes the substrate P at a reference position. Yes.

  The droplet discharge head 1001 is a multi-nozzle type droplet discharge head including a plurality of discharge nozzles, and the longitudinal direction and the X-axis direction are made to coincide. The plurality of discharge nozzles are provided on the lower surface of the droplet discharge head 1001 at regular intervals. From the discharge nozzle of the droplet discharge head 1001, the wiring pattern ink containing the conductive fine particles is discharged onto the substrate P supported by the stage 1007.

  An X-axis direction drive motor 1002 is connected to the X-axis direction drive shaft 4. The X-axis direction drive motor 1002 is composed of a stepping motor or the like, and rotates the X-axis direction drive shaft 4 when a drive signal in the X-axis direction is supplied from the control device CONT. When the X-axis direction drive shaft 4 rotates, the droplet discharge head 1001 moves in the X-axis direction.

The Y-axis direction guide shaft 1005 is fixed so as not to move with respect to the base 1009.
The stage 7 includes a Y-axis direction drive motor 3. The Y-axis direction drive motor 1003 is a stepping motor or the like, and moves the stage 7 in the Y-axis direction when a drive signal in the Y-axis direction is supplied from the control device CONT.

The control device CONT supplies a droplet discharge control voltage to the droplet discharge head 1001.
In addition, a drive pulse signal for controlling movement of the droplet discharge head 1001 in the X-axis direction is supplied to the X-axis direction drive motor 1002, and a drive pulse signal for controlling movement of the stage 1007 in the Y-axis direction is supplied to the Y-axis direction drive motor 1003. Supply.

  The cleaning mechanism 1008 is for cleaning the droplet discharge head 1001. The cleaning mechanism 1008 includes a Y-axis direction drive motor (not shown). The cleaning mechanism moves along the Y-axis direction guide shaft 1005 by driving the Y-axis direction drive motor. The movement of the cleaning mechanism 1008 is also controlled by the control device CONT.

  Here, the heater 1015 is means for heat-treating the substrate P by lamp annealing, and performs evaporation and drying of the solvent contained in the liquid material disposed on the substrate P. The heater 1015 is also turned on and off by the control device CONT.

  The droplet discharge device IJ is arranged in the X axis direction on the lower surface of the droplet discharge head 1001 with respect to the substrate P while relatively scanning the droplet discharge head 1001 and the stage 1007 supporting the substrate P. Droplets are ejected from a plurality of ejection nozzles.

  FIG. 6 is a diagram for explaining the principle of discharging a liquid material by a piezo method. In FIG. 6, a piezo element 1022 is installed adjacent to a liquid chamber 1021 that contains a liquid material (wiring pattern ink, functional liquid). The liquid material is supplied to the liquid chamber 1021 via a liquid material supply system 1023 including a material tank that stores the liquid material. The piezo element 1022 is connected to the drive circuit 1024, and a voltage is applied to the piezo element 1022 via the drive circuit 1024 to deform the piezo element 1022, whereby the liquid chamber 1021 is deformed and the liquid is discharged from the discharge nozzle 1025. Material is dispensed. In this case, the amount of distortion of the piezo element 1022 is controlled by changing the value of the applied voltage. Further, the strain rate of the piezo element 1022 is controlled by changing the frequency of the applied voltage. Since the droplet discharge by the piezo method does not apply heat to the material, it has an advantage of hardly affecting the composition of the material.

  Here, the description returns to the method of manufacturing the touch panel. 7 and 8 are diagrams showing a manufacturing process of the touch panel 100. FIG. These process drawings show a process of forming the structure shown in FIG. 2 (intersection of bridge wiring and routing wiring 60).

First, the electrode film forming step S10 will be described.
In the electrode film forming step S10, for example, droplets of a liquid material containing, for example, ITO particles are selectively placed on the substrate 1 which is a glass substrate, for example, by the droplet discharge device IJ shown in FIG. Specifically, an X electrode 10 including an island electrode portion 12 and a bridge wiring 11 is formed on the substrate 1 (first electrode forming step), and an island electrode portion which is a part of the Y electrode 20 22 (second electrode forming step), and a pattern of a liquid material including the island-shaped electrode portion 12 and the first layer 60a of the lead-out wiring 60 extended from the island-shaped electrode portion 22 is formed. Thereafter, the liquid material (droplet) disposed on the substrate 1 is dried. In order to obtain an electrode with uniform characteristics, it is effective to fire the pattern of the liquid material at a high temperature of 200 ° C. or higher. In addition, as a liquid material for forming the ITO electrode, a dispersion liquid of indium and tin metal particles, which are ITO precursor particles, may be used. The pattern of the ITO precursor particles is 200 to 300 ° C. By firing at a moderate temperature, the dispersing agent in which indium and tin are dispersed is removed, and the metal particles are oxidized and fired to form an ITO electrode in which highly transparent ITO particles are gathered.
As a result, as shown in FIG. 7A, the X electrode 10 (island electrode portion 12, bridge wire 11), the island electrode portion 22, and the lead wire 60 made of an aggregate of ITO particles are formed on the substrate 1. The first layer 60a is formed.

In the electrode film forming step S10 of this embodiment, an ITO film is formed by discharging droplets containing ITO particles. In addition to this, a liquid containing IZO (registered trademark) particles is also used. A transparent conductive film made of IZO (registered trademark) may be formed using droplets. Also, a transparent conductive film made of polythiophene or polyaniline-based organic polymer may be formed. When a liquid in which the organic polymer is dissolved in water or a solvent is disposed, baking at a low temperature of about 30 minutes at 120 ° C. is necessary.
In the electrode film forming step S10, a pattern forming method using a photolithography method can be used instead of the droplet discharge method. That is, after forming an ITO film on almost the entire functional surface 1a of the substrate 1 by sputtering or the like, the ITO film is patterned by using a photolithography method and an etching method, whereby the X electrode 10 (island electrode portion 12, You may make it form the 1st layer 60a of the bridge | bridging wiring 11), the island-shaped electrode part 22, and the routing wiring 60. FIG.

Next, the process proceeds to auxiliary wiring formation step S20.
In the auxiliary wiring forming step S20, liquid droplets including the constituent material of the second layer 60b of the routing wiring 60 are discharged and arranged on the first layer 60a by the droplet discharge device IJ. As the liquid material for forming the second layer 60b, for example, a liquid material containing silver particles can be used. Thereafter, the discharged droplets are dried. As a result, as shown in FIG. 7B, a low-resistance second layer 60b is formed on the first layer 60a, and a routing wiring 60 having a two-layer structure is formed on the substrate 1 outside the input region 2. The

  Examples of the liquid material forming the second layer 60b of the routing wiring 60 include a liquid material containing silver particles, a liquid material containing metal particles such as Au, Al, Cu, and Pd, graphite, and carbon nanotubes. Liquid materials can be used. Metal particles and carbon particles are dispersed in the liquid material in the form of nanoparticles and nanowires. When the second layer 60b is a metal film, a liquid material containing an organometallic compound may be used.

Next, the insulating film forming step S30 and the bridge wiring forming step S40 are sequentially performed.
FIG. 9 is a plan explanatory view showing the insulating film forming step S30 and the bridge wiring forming step S40 more specifically. FIGS. 9B and 9C are plan views corresponding to FIG. 7C and showing a region where the bridge wiring 21 is formed. FIG. 9D is a plan view corresponding to FIG.

Below, it demonstrates, referring FIG.7 and FIG.9.
In the insulating film forming step S30, the first step of forming the insulating film body 31 covering at least the bridge wiring 11 and the recess 31b generated in the surface 31a of the insulating film body 31 formed in the first step are filled to fill the surface 31a. And a second step of flattening. In this second step, when the insulating film body 31 is formed, bleeding occurs, and the insulating film body is filled by filling the concave portion 31b (shown by a one-dot chain line in FIG. This is a step of flattening the surface 31a of 31 (insulating film 30).

  In the first step, as shown in FIG. 7C and FIG. 9B, the droplet discharge device IJ causes the island-like electrode portion 12 to fill the bridge wiring 11 of the X electrode 10 at the intersection K, The insulating film main body 31 is formed by selectively disposing liquid droplets (functional liquid) containing an insulating film forming material between the gaps 22.

At this time, in the insulating film main body 31, both ends are raised due to so-called bleeding, and the central portion is depressed, so that a concave portion 31 b is formed on the surface 31 a. Therefore, in the second step after the insulating film main body 31 is dried, as shown in FIG. 9C, a liquid droplet L containing the insulating film forming material is applied to the recess 31b generated in the first step. As a result, the flattened portion 32 that fills the concave portion 31b excluding the portion that has spread out is formed, and the surface 31a is flattened. At this time, since the insulating film main body 31 formed earlier easily absorbs the solvent of the droplet L disposed in a small amount on the liquid film L, the viscosity of the liquid L sucked up by the solvent is quickly increased and the flattening portion 32 is formed.
Thereafter, the liquid material on the substrate 1 is heated and baked and dried and solidified to form the insulating film 30 including the bridge wiring 11. Here, since the insulating film main body 31 and the planarizing portion 32 are formed of the same material, the insulating film 30 is integrally formed although an interface exists.

  When forming the insulating film 30, it is preferable to dispose droplets at least in a region on the bridge wiring 11 without a gap. As a result, the insulating film 30 having no holes or cracks reaching the bridge wiring 11 can be formed, and insulation failure in the insulating film 30 and disconnection of the bridge wiring 21 are prevented.

Subsequently, as shown in FIG. 7C, droplets are selectively placed also on the region on the lead wiring 60. Thereafter, the liquid material on the substrate 1 is heated and baked and dried and solidified to form a wiring protective film 62 that covers the routing wiring 60.
As the liquid material, for example, a liquid material containing polysiloxane, an acrylic resin, or a liquid material containing an acrylic monomer can be used.

Next, the process proceeds to the bridge wiring formation step S40.
In the bridge wiring formation step S40, as shown in FIGS. 7D and 9D, the liquid material containing ITO particles is formed on the island-like electrode portions 22 and the insulating film 30 that are arranged adjacent to each other. Droplets are arranged in a wiring shape. Thereafter, the liquid material on the substrate 1 is dried and solidified. Thereby, the bridge wiring 21 that connects the island-shaped electrode portions 22 is formed. When the bridge wiring 21 is formed, as described above, the surface 31a of the insulating film 30 at the intersection K serving as a base is flattened by filling the concave portion 31b. Therefore, the bridge wiring 21 can be formed without bending. it can.
In addition, as a liquid material used for formation of the bridge | bridging wiring 21, it can also form using the liquid material containing IZO (trademark) particle | grains and ZnO particle | grains other than the liquid material containing ITO particle | grains mentioned above.

  When forming the bridge wiring 21, as shown in FIG. 9D, in the bridge wiring forming step S40, it is preferable to form the bridge wiring 21 using the same liquid material as in the electrode film forming step S10. That is, it is preferable to use the same material as the constituent material of the X electrode 10 and the island-like electrode portion 22 as the constituent material of the bridge wiring 21.

Next, the process proceeds to the planarization film forming step S50.
In the planarization film forming step S50, as shown in FIG. 8A, a planarization film 40 made of an insulating material is formed on almost the entire functional surface 1a for the purpose of planarizing the functional surface 1a of the substrate 1.
The planarizing film 40 can be formed using a liquid material similar to the liquid material for forming the insulating film 30 used in the insulating film forming step S30. It is preferable to use a material.

Next, the process proceeds to the protective substrate bonding step S60.
In the protective substrate bonding step S60, as shown in FIG. 8B, an adhesive is disposed between the protective substrate 50 and the planarizing film 40 that are separately prepared, and protection is performed via the adhesive layer 51 made of such an adhesive. The substrate 50 and the planarizing film 40 are bonded together. The protective substrate 50 may be an optical element substrate such as a polarizing plate or a retardation plate in addition to a transparent substrate made of glass, plastic, or the like. As the adhesive constituting the adhesive layer 51, a transparent resin material or the like can be used.

Next, the process proceeds to shield layer forming step S70.
In the shield layer forming step S70, as shown in FIG. 8C, the shield layer 70 made of a conductive film is formed on the back surface 1b of the substrate 1 (the surface opposite to the functional surface 1a). The shield layer 70 can be formed using a known film formation method such as a vacuum film formation method, a screen printing method, an offset method, or a droplet discharge method. For example, when the shield layer 70 is formed using a printing method such as a droplet discharge method, a liquid material containing ITO particles or the like used in the electrode film forming step S10 and the bridge wiring forming step S40 can be used. .
In addition to the method of forming the shield layer 70 by film formation on the substrate 1, a film having a conductive film formed on one surface or both surfaces thereof is separately prepared, and the film is bonded to the back surface 1b of the substrate 1. The conductive film on the film may be used as the shield layer 70.

  In the present embodiment, the shield layer 70 is implemented at the end of the touch panel manufacturing process, but the shield layer 70 can be formed at an arbitrary timing. For example, the substrate 1 on which the shield layer 70 is formed in advance can be used for the electrode film forming step S10 and subsequent steps. Moreover, you may arrange | position a shield layer formation process between arbitrary processes from electrode film-forming process S10 to protective substrate joining process S60.

  Further, in the present embodiment, the shield layer 70 is formed on the back surface 1b of the substrate 1, but the shield layer 70A is provided on the functional surface 1a side of the substrate 1 like the touch panel 100A according to the modification shown in FIG. In the case of forming, a step of forming the shield layer 70A and a step of forming the insulating film 80A are executed prior to the electrode film forming step S10. Also in this case, the shield layer 70A can be formed by the same method as in the shield layer forming step S70. The formation process of the insulating film 80A can be the same as the insulating film formation process S30, for example.

According to the manufacturing method of the touch panel 100 described in detail above, the following effects can be obtained.
First, in the manufacturing method of the present embodiment, the X electrode 10 (island electrode portion 12, bridge wiring 11) and the island electrode portion 22 constituting the Y electrode 20 are formed on the same surface on the substrate 1, and thereafter Then, an insulating film 30 is formed in a region on the bridge wiring 11 by using a droplet discharge method, and then a bridge wiring 21 for connecting the island-shaped electrode portions 22 is further formed by using the droplet discharge method. Thus, by forming the connection structure of the Y electrode 20 intersecting with the X electrode 10 by using a droplet discharge method which is a printing method, the number of man-hours can be reduced as compared with the conventional case, and the touch panel manufacturing cost can be reduced. Can be suppressed.

  More specifically, in the conventional connection structure forming step, after the step shown in FIG. 7A, (1) a step of forming an interlayer insulating film covering the X electrode 10 and the island-like electrode portion 22; 2) a step of forming a contact hole in the interlayer insulating film for bridging the bridge wiring between the adjacent island-shaped electrode portions 22, and (3) patterning the bridge wiring in a region including the contact hole to form the island-shaped electrode portion 22. And a step of connecting each other.

As is apparent from a comparison between the above-described conventional process and the process of the present embodiment, in the manufacturing method according to the present embodiment, a photolithography process (and an etching process) for forming contact holes in the interlayer insulating film in the conventional process. In addition, a photolithography process and an etching process for patterning the bridge wiring are also unnecessary.
Therefore, according to the manufacturing method of the present embodiment, the costly photolithography process can be reduced, and the manufacturing cost of the touch panel can be reduced. Further, in the droplet discharge method, since droplets are selectively arranged only in the region where each film is formed, the amount of material used can be suppressed, and the raw material cost also contributes to a reduction in manufacturing cost.

  Further, in the present embodiment, since the surface 31a is flattened by filling the concave portion 31b generated when the insulating film main body 31 is formed with the flattening portion 32, the surface 31a is not bent on the surface 31a. The bridge wiring 21 can be formed in a flat film shape. Therefore, in the present embodiment, it is possible to manufacture a high-quality touch panel 100 that does not cause disconnection or the like. In particular, in this embodiment, since the flattening portion 32 is formed of the same material as that of the insulating film body, it is not necessary to separately prepare a material for forming the flattening portion 32 and the first step is followed by the first step. Two steps can be performed, and the touch panel 100 that can contribute to reduction in manufacturing cost and improvement in manufacturing efficiency, low cost, high quality, and high yield can be obtained.

<Second Embodiment>
Next, the manufacturing method of the touch panel of the 2nd Embodiment of this invention is demonstrated.
In the first embodiment, when the planarizing portion 32 is formed, the same material as that of the insulating film body 31 is used. However, in the second embodiment, the same material as that of the bridge wiring 21 is used.

  That is, in the present embodiment, the flattened portion 32 is formed by disposing a liquid material droplet containing ITO particles in the recess 31b of the insulating film main body 31 generated in the first step in the insulating film forming step S30. In addition, as a liquid material used for forming the bridge wiring 21, in addition to the liquid material containing the ITO particles described above, when using a liquid material containing IZO (registered trademark) particles or ZnO particles, similarly to the recess 31b, A droplet of the liquid material is placed.

  Here, the recess 31b generated in the insulating film main body 31 is generated only on the surface 31a, and the insulating property with respect to the bridge wiring 11 is ensured by the presence of the insulating film main body 31. A short circuit with 11 is avoided.

  In the present embodiment, in addition to obtaining the same operations and effects as in the first embodiment, it is possible to perform the bridge wiring forming step S40 following the second step, thereby reducing the manufacturing cost and the manufacturing efficiency. Since at least a part of the bridge wiring 21 can be thickened, the resistance value can be reduced and the strength can be improved.

[Display device]
Next, a display device provided with the touch panel of the present invention will be described. In the present embodiment, a liquid crystal display device including a touch panel will be described as an example of the display device. FIG. 11 is a schematic view of a liquid crystal display device 500 according to an embodiment of the present invention, and shows a cross-sectional view taken along line HH ′ in (a) a plan view and (b) a plan view.

As shown in FIG. 10A, the liquid crystal display device 500 includes an element substrate 410, a counter substrate 420, and an image display region 410a.
The element substrate 410 is a rectangular substrate having a wider plane area than the counter substrate 420.
The counter substrate 420 is an image display side in the liquid crystal display device 500, and is a transparent substrate formed of glass, acrylic resin, or the like. The counter substrate 420 is bonded to the central portion of the element substrate 410 through a sealing material 452.
The image display area 10 a is a planar area of the corresponding substrate 420 and is an inner area of the peripheral parting line 453 provided along the inner periphery of the sealing material 452.

  In the periphery of the counter substrate 420 in the element substrate 410, the data line driving circuit 401, the scanning line driving circuit 404, the connection terminal 402 connected to the data line driving circuit 401 and the scanning line driving circuit 404, and the counter substrate 420. A wiring 405 for connecting the scanning line driving circuits 404 arranged to face each other is disposed.

Next, a cross section of the liquid crystal display device 500 will be described.
A pixel electrode 409, an alignment film 418, and the like are stacked on the surface of the element substrate 410 on the liquid crystal layer 450 side.
A light shielding film (black matrix) 423, a color filter 422, a common electrode 425, an alignment film 429, and the like are stacked on the surface of the counter substrate 420 on the liquid crystal layer 450 side.
A liquid crystal layer 450 is sandwiched between the element substrate 410 and the counter substrate 420.
The touch panel 100 of the present invention is disposed on the outer surface (opposite side of the liquid crystal layer 450) of the counter substrate 420 with the adhesive layer 101 interposed therebetween.

According to the liquid crystal display device described above, the following effects can be obtained.
The touch panel 100 provided in the liquid crystal display device 500 is formed with an electrode for position detection and an insulating film that crosses the electrodes by a droplet discharge method. Thereby, since the cost concerning manufacture of a touch panel is reduced, it can be set as the liquid crystal display device which suppressed manufacturing cost.
The touch panel provided in the liquid crystal display device may be the touch panel 100A that is a modification of the first embodiment or the touch panel 200 of the second embodiment. These touch panels are also manufactured by a process of forming a film by a droplet discharge method, and the manufacturing cost is reduced. Therefore, the manufacturing cost of the liquid crystal display device can be suppressed.

In the liquid crystal display device of this embodiment, it is preferable that each layer of the touch panel is formed on the outer surface (opposite side of the liquid crystal layer 450) of the counter substrate 420. According to this, the counter substrate 420 of the liquid crystal display device and the substrate 1 of the touch panel can be shared, so that the manufacturing cost can be further reduced and the liquid crystal display device can be reduced in weight.
Further, in the present embodiment, the liquid crystal display device has been described, but besides this, the touch panel of the present invention can also be suitably used in display devices such as an organic EL device and an electrophoretic display device.

Next, an example of an electronic device having the touch panel of the present invention or a liquid crystal display device including the touch panel will be described. FIG. 11 is a perspective view showing a mobile personal computer 1100. A mobile personal computer 1100 includes a display portion 1101 and a main body portion 1103 having a keyboard 1102. The mobile personal computer 1100 includes the liquid crystal display device 500 of the above embodiment in the display unit 1101.
According to the mobile personal computer 1100 having such a configuration, since the touch panel of the present invention is used for the display unit, an electronic device with reduced manufacturing cost can be obtained.

  In addition, said electronic device is an example of the electronic device of this invention, Comprising: The technical scope of this invention is not limited. For example, the touch panel according to the present invention can be suitably used for a display unit of a mobile phone, a portable audio device, a PDA (Personal Digital Assistant), or the like.

  As described above, the preferred embodiments according to the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  For example, in the above-described embodiment, the configuration in which the planarizing portion 32 is formed of the same material as the insulating film body 31 or the same material as the bridge wiring 21 is illustrated, but the present invention is not limited to this, and other materials are used. However, it is preferable to use a material used for manufacturing the touch panel 100.

  DESCRIPTION OF SYMBOLS 1 ... Board | substrate, 10 ... X electrode (1st electrode), 11 ... Bridge wiring, 20 ... Y electrode (2nd electrode), 22 ... Island-like electrode part (electrode film), 30 ... Insulating film, 31 ... Insulating film main body 31a ... surface, 31b ... concave, 32 ... flattened portion, 100 ... touch panel, K ... intersection

Claims (8)

A method of manufacturing a touch panel having a plurality of first electrodes and a plurality of second electrodes formed on one surface side of a substrate and extending in a direction intersecting each other,
An electrode film forming step of forming a plurality of the first electrodes and an electrode film having a shape in which the second electrodes are separated and separated from each other at an intersection with the first electrodes on the substrate;
An insulating film forming step of forming an insulating film on at least the first electrode at the intersection using a printing method;
A bridge wiring forming step of forming a bridge wiring connecting the second electrodes spaced apart at the intersection via the insulating film using a printing method,
The insulating film forming step includes at least a first step of forming an insulating film body on the first electrode, and filling the recesses formed on the surface of the insulating film body formed in the first step, A method for manufacturing a touch panel, comprising: a second step of flattening. In the manufacturing method of the touch panel of Claim 1,
A method for manufacturing a touch panel, wherein the recess is filled with a material used when forming the insulating film main body. In the manufacturing method of the touch panel of Claim 1,
A method for manufacturing a touch panel, wherein the recess is filled with a material used for forming the bridge wiring.   A display device manufacturing method comprising a step of manufacturing a touch panel by the manufacturing method according to claim 1.   An electronic device manufacturing method comprising a step of manufacturing a display device by the manufacturing method according to claim 4. A touch panel having a plurality of first electrodes and a plurality of second electrodes formed on one surface side of the substrate and extending in a direction intersecting each other,
The second electrode separated and separated at the intersection with the first electrode on the substrate;
An insulating film formed on at least the first electrode at the intersection;
A bridge wiring connecting the second electrodes spaced apart at the intersection via the insulating film;
The touch panel, wherein the insulating film has an insulating film main body and a flattening portion that is embedded in a recess formed on the surface of the insulating film main body and flattens the surface. The touch panel according to claim 6.
The touch panel according to claim 1, wherein the planarizing portion is formed of the same material as the insulating film body. The touch panel according to claim 6.
The touch panel according to claim 1, wherein the planarizing portion is formed of the same material as the bridge wiring.

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