JP2005267467A - Touch panel, and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a touch panel excellent in impact resistance, capable of securing a wide effective input area, and having an excellent operability, by adopting a glass material of high rigidity and thick plate thickness to be hardly deflected, as a material for an upper substrate. <P>SOLUTION: In this touch panel arranged opposedly with the upper substrate and a lower substrate arranged with a pair of transparent electrodes via a prescribed thickness of sealing material to oppose transparent electrode faces each other, and having a lead-in electrode connected to the transparent electrode of each of the substrates, and dot spacers provided matrix-like on the transparent electrode of the lower substrate, the upper substrate comprises the glass material having 0.3-0.4 mm of thickness and has a concave curved part in an area along an inner circumferential face of the sealing material of the upper substrate, and a clearance between the upper substrate and the lower substrate in the concave curved part is set slightly smaller than the thickness of the sealing material. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a touch panel that is arranged on a display screen of a liquid crystal display panel and allows a user to input data by directly pressing the information display screen with a finger, a pen, or the like according to an instruction of the see-through screen.

  A touch panel as an input switch of a display device in the prior art is arranged and used on a display surface of the display device. In this touch panel, an upper substrate composed of a glass plate and a transparent electrode formed on the lower surface thereof, and a lower substrate composed of the glass plate and a transparent electrode formed on the upper surface thereof are separated from each other with a predetermined gap therebetween. Are arranged so as to face each other and are attached with a sealing material. In this touch panel, when the upper part of the upper substrate is pressed with an input pen or a finger, the upper substrate is bent and the transparent electrode of the upper substrate contacts the transparent electrode of the lower substrate at the pressing point. Then, the coordinates of the contact point are detected by measuring the electric resistance, and the input information is read. As described above, a touch panel using two glass substrates is often used in a device such as a car navigation system. The touch panel is arranged on a liquid crystal panel screen, and a user displays an information display screen with a finger or a pen in accordance with a fluoroscopic screen instruction. Press directly to enter data. For this reason, it is necessary to use a flexible material on the upper substrate that presses the surface with a fingertip or an input pen, so that it is necessary to use a flexible material. Micro glass is a special glass material that has both strength and flexibility. Many examples of using are disclosed (for example, refer to Patent Document 1). Hereinafter, specific examples of the touch panel and the manufacturing method thereof in the related art will be described with reference to the drawings.

  5A and 5B show a touch panel in the prior art, FIG. 5A is a plan view, and FIG. 5B is a cross-sectional view taken along line XX in FIG. As shown in FIG. 5, the lower substrate 2 is made of a soda glass plate having a thickness of 1.1 mm, and the transparent electrode 4 is formed on the surface of the lower substrate 2. The transparent electrode 4 is formed by forming an ITO film made of indium tin oxide having a thickness of about 50 to 4000 angstroms by sputtering or CVD, and forming a pattern by etching. Further, lead-out electrodes 8a and 8b that are electrically connected to the transparent electrode 4 and are arranged in a square shape are formed. The routing electrodes 8a and 8b are formed by printing a silver paste film having a thickness of about 1 to 20 μm in a predetermined pattern and baking it at 130 ° C. for about 60 minutes to have a thickness of 3 to 5 μm and a width of about 1 mm. As a material for the lead-out electrode, a conductive paste in which a conductive powder such as a metal such as silver or nickel or carbon is dispersed in a resin binder is used and formed by screen printing.

  Next, dot spacers 5 are formed in a matrix on the surface of the transparent electrode 4. The dot spacer 5 is formed in a square or circular shape having a size of about 30 to 40 μm and a height from the substrate of about 5 to 8 μm. The dot spacers 5 are formed by first printing an ink made of an epoxy resin-related ultraviolet curable resin in a matrix by a silk screen printing method. Thereafter, the printed ultraviolet curable resin is irradiated with ultraviolet rays to cure the ultraviolet curable resin, thereby forming dot spacers 5 having a height of 5 to 8 μm and a pitch of 2 to 4 mm.

  The upper substrate 1 is made of a micro glass plate having a thickness of 0.2 mm, and the transparent electrode 3 and the routing electrodes 7a and 7b are formed on the surface of the upper substrate 1 in the same manner as the lower substrate 2 described above. An example of the micro glass used as the upper substrate 1 is borosilicate glass.

  Next, the sealing material 6 is printed on the periphery of the lower substrate 2, and the lower substrate 2 and the upper substrate 1 are overlapped so that the transparent electrodes 3 and 4 face each other. This sealing material 6 is for bonding the upper substrate 1 and the lower substrate 2, and an epoxy resin adhesive or the like is selected and formed with a width in the range of 1 to 2.5 mm by a method such as screen printing. . A spacer member such as a plastic ball or fiber glass having a required size is dispersed in the seal material 6. The spacer member serves to hold the upper substrate 1 and the lower substrate 2 in a required gap. doing.

  Thereafter, the upper and lower substrates on which the upper substrate 1 and the lower substrate 2 are overlapped are set on a curing jig, and the sealing material 6 is baked by applying pressure and heating for a predetermined time. As a result, the upper substrate 1 and the lower substrate 2 are adhered to each other with the sealing material 6 to manufacture the touch panel 10. At this time, the gap e between the upper and lower substrates is set in the range of 8 to 10 μm. In addition, the above-mentioned routing electrode is collected on one side of the touch panel, and is connected to an end portion of the connector 9 which is an FPC crimp electrode.

Japanese Patent Laying-Open No. 2003-271313 (first page, FIGS. 3 to 6)

  However, in the conventional touch panel, the lead-out electrodes 7a, 7b, 8a, and 8b inside the sealing material 6 are gathered on one side of the touch panel 6 as shown in part A of FIG. It has a structure that is electrically connected to the end portion of the connector 9 that is a crimp electrode for FPC to establish conduction, and a part of the sealing material and the routing electrode cross each other. The lead-out electrode is formed by printing and baking epoxy or the like (silver paste) in which fine particles such as silver of about 3 to 5 μm are added by diffusion, and then epoxy resin or the like in which 8 to 10 μm spacer particles are added to the sealing material. Is screen-printed, heated and pressed to fix the adhesive. At this time, it is necessary to set the gap e between the upper and lower substrates to be small (8 to 10 μm), and the routing electrode is hardened first. At the portion where the routing electrodes intersect, the fine particles added to both are in a state of being intertwined.

  For this reason, during pressurization and firing of the sealing material, the spacer particles in the sealing material on the routing electrode are routed at the intersection of the sealing material and the routing electrode, the spacer particles remain on the electrode, and the upper substrate has a convex shape at that portion. The phenomenon that swells (swells) occurs. The amount is below the level that can be visually recognized within 10 μm, but the upper substrate is 0.2 mm thick and stress is applied both when not in use and at the time of use. was there. In particular, in the multi-cavity manufacturing process, a plurality of touch panel units are attached through a sealing material, and then scribed and cut, so if there is a waviness of about 10 μm, horizontal cracks are likely to occur in this part during scribing, For touch panels with poor vibration and impact conditions, such as for car navigation systems, there was a risk of damage to the upper substrate from this part.

  As described above, the upper substrate made of a glass material is preferably thin in terms of obtaining flexibility, but the upper substrate made of a 0.2 mm micro glass material is inferior in impact resistance including process yield, and the material cost is also high. There was a problem of being expensive. In this respect, since the impact resistance is good and the material cost is low, it is preferable to use a glass material having a plate thickness of 0.4 mm, which is frequently used in liquid crystal panels, as the material for the upper substrate. FIG. 6 shows an example in which only the upper substrate is made of a glass material having a thickness of 0.4 mm while maintaining the structure of the conventional touch panel, and FIGS. 7 and 8 show the upper substrate 11 in the vicinity of the routing electrode. It is a partial expanded sectional view which shows the state pressed. As shown in FIG. 7, when the distance m to the dot spacer 5 closest to the routing wiring 8a is the same value (about 4 mm) as the upper substrate having a thickness of 0.2 mm, the rigidity of the upper substrate 11 is large. The amount of bending is small, non-contact failure, or the pressing load increases. Further, as shown in FIG. 8, if the distance m between the lead wiring 8a and the dot spacer 5 is increased, non-contact failure can be prevented, but the input point B and the contact point P do not coincide with each other, and the error in linearity may increase. In addition, the effective input area is also narrowed. Thus, since the upper substrate made of a glass material having a thickness of 0.4 mm is inferior in flexibility, there is a problem that the pressing load increases and the operability is deteriorated. As shown in FIG. 6, there is a problem that the effective input area b becomes narrower than the effective input area a in the case of the upper substrate 1 having a thickness of 0.2 mm. For this reason, it is difficult to employ an upper substrate made of a glass material having a thickness of 0.4 mm.

(Object of invention)
The present invention solves the above-mentioned problems, adopts a glass material having a plate thickness of 0.3 mm to 0.4 mm as a material for the upper substrate of the touch panel, and improves the structure of the touch panel. An object is to provide a touch panel that can secure an input area and has excellent operability.

  In order to achieve the above-mentioned object, an upper substrate on which a pair of transparent electrodes are arranged and a lower substrate are arranged to face each other through a seal material having a predetermined thickness so that the transparent electrode surfaces face each other. In the touch panel having a routing electrode connected to the transparent electrode and a dot spacer provided in a matrix on the transparent electrode of the lower substrate, the upper substrate is made of a glass material having a thickness of 0.3 to 0.4 mm. It has a concave curved portion in a region along the inner periphery of the sealing material, and the gap between the upper substrate and the lower substrate in the concave curved portion is set slightly smaller than the thickness of the sealing material.

Further, the minimum gap value between the upper substrate and the lower substrate in the concave curved portion is set in a range of 1.5 to 2 μm.
The upper substrate has a shape in which the vicinity of the center is convexly curved outward, and the value of the gap between the upper substrate and the lower substrate near the center is set in the range of 8 to 10 μm. To do.
In addition, the distance between the routing electrode and the dot spacer closest to the routing electrode is set in a range of 5 to 10 mm.
Further, the height of the routing electrode and the dot spacer is approximately the same in a range of 2 to 4 μm.
Further, the dot spacer pitch is set in a range of 5 to 6 mm.
Moreover, the thickness of the sealing material is set in a range of 5 to 8 μm.

  Further, in the method of manufacturing a touch panel, in which an upper substrate and a lower substrate on which a pair of transparent electrodes are arranged are overlapped with a sealing agent so that the transparent electrode surfaces face each other, and the upper substrate and the lower substrate are bonded. A pair of upper and lower substrates that are laminated with a lower substrate, and a plurality of sets of upper and lower substrates are laminated through a frame-shaped slip sheet having a window, and are sealed by applying pressure and heating for a predetermined time. And the upper substrate and the lower substrate are bonded to each other, the inner shape of the window portion of the interleaf paper is smaller than the inner shape of the seal material after firing, and the inner side of the seal material By setting the difference between each side and each side of the window corresponding to each side on the inner side of the sealing material in a range of 0.4 to 0.6 mm, an area along the inner periphery of the sealing material of the upper substrate is set. A concave curved portion is formed, and the gap between the upper substrate and the lower substrate in the concave curved portion is Characterized in that it slightly smaller than the of.

  As described above, the present invention adopts a glass material having a thickness of 0.3 mm to 0.4 mm, which is inferior in flexibility but has good impact resistance, as a material for the upper substrate of the touch panel, and in the sealing material of the upper substrate. By forming a concave curved portion in a region along the circumference, and forming a gap between the upper substrate and the lower substrate in the concave curved portion slightly smaller than the thickness of the sealing material, the impact input is good and a wide effective input area Can be ensured and a touch panel having excellent operability and a method for manufacturing the same can be provided.

  FIG. 1 shows a touch panel according to an embodiment of the present invention, FIG. 1 (a) is a plan view, FIG. 1 (b) is a sectional view taken along line XX in FIG. 1 (a), and FIG. 2A is a cross-sectional view of a portion B in FIG. 1B, and FIG. 2B is a cross-sectional view of a portion C in FIG. 1B. Moreover, FIG. 3 is a figure which shows the manufacturing process of the touch panel of this embodiment, and FIG. 4 is a figure which shows the slip used in the manufacturing process of the touch panel of this embodiment. The touch panel in the present embodiment uses a 0.4 mm glass material on a 7-inch size upper substrate, and realizes a wide effective input area with excellent impact resistance by making the upper substrate a predetermined curved shape. Its basic structure is similar to the prior art. Therefore, the same constituent elements as those in the prior art are given the same numbers and the description thereof is omitted. Hereinafter, the touch panel and the manufacturing method thereof according to the present embodiment will be described with reference to FIGS.

  As shown in FIG. 1, the touch panel 20 in the present embodiment is disposed so that the upper substrate 11 and the lower substrate 2 provided with a pair of transparent electrodes (not shown) face each other so that the transparent electrode surfaces face each other. 16 is attached. For the upper substrate 11, a 7-inch glass material having a thickness of 0.4 mm is used. The upper substrate 11 is formed with a concave curved portion 14 in a region along the inner periphery of the sealing material 16, and the gap between the upper substrate 11 and the lower substrate 2 in the concave curved portion 14 is slightly smaller than the thickness of the sealing material. It is set small. Further, the vicinity of the center of the upper substrate 11 is curved in a convex shape toward the outside, and the gap between the upper substrate 11 and the lower substrate 2 in the vicinity of the center is set slightly larger than the thickness of the sealing material. Yes. By forming the upper substrate 11 in a predetermined curved shape in this way, the pressing load near the inner periphery of the sealing material 16 can be reduced, the area of the effective input area s can be increased, and the entire effective input area s can be increased. It is possible to obtain a touch panel 20 that can equalize the pressing load and is excellent in impact resistance and operability. Next, the touch panel 20 will be described in detail together with the manufacturing method.

  As shown in FIGS. 1 and 2, the lower substrate 2 is made of a soda glass plate having a thickness of 1.1 mm, and a transparent electrode (not shown) is formed on the surface of the lower substrate 2 in the same manner as in the prior art. The lead-out electrodes 18a and 18b arranged in a square shape are electrically connected to the transparent electrode. The lead-out electrodes 18a and 18b are set to have a thickness h of 2 to 4 μm, which is thinner than the conventional one. The lead-out electrodes 18a and 18b are formed by screen printing using a silver paste as a material as in the prior art, but the particle size of the highly conductive fine particles added to the silver paste is reduced to about 1 μm. As a means for setting and managing the dimensions of the lead-out electrodes 18a and 18b, a screen printing plate having a fine mesh of about 600 mesh and a thin emulsion of the mask pattern portion is used to form a thin silver paste ink. After the curing (or after about 90% curing), the outer periphery rolls with a precision finish while heating to about 100 ° C. to make the value of the height h uniform. The height is controlled by the laser detection method.

  Next, dot spacers 15 are formed in a matrix on the surface of the transparent electrode. The shape and size of the dot spacer 15 may be the same as the conventional one, but the value of the height h from the surface of the transparent electrode is set to 2 to 4 μm, which is thinner than the conventional one, and the above-described lead electrodes 18a and 18b It is formed at a height substantially equal to the value of the thickness h. Further, the value of the pitch d of the dot spacers 15 is conventionally set to a large value of about 5 to 6 mm, which was 2 to 4 mm. In particular, the value of the distance n between the routing electrodes 18a and 18b and the dot spacer 15 adjacent to and closest to the routing electrode is conventionally set to about 5 to 10 mm. The dot spacers 15 are formed by using a screen printing plate in which the emulsion of the mask pattern portion is thinly formed with a fine mesh of about 600 mesh as in the case of the above-described lead electrodes, and an epoxy resin-based ink is formed thinly. Then, after curing (or after curing about 90%), the roller of fine finishing is rolled while heating to about 100 ° C., and the value of height h is made constant. The height is controlled by the laser detection method.

  The upper substrate 11 is made of a glass plate having a thickness of 0.4 mm, and a transparent electrode (not shown) and a lead-out electrode (not shown) are formed on the surface of the upper substrate 11 like the lower substrate 2 described above. As the glass used as the upper substrate 11, a glass having a general plate thickness of 0.4 mm that is frequently used in liquid crystal panels was used.

  Next, the sealing material 16 is printed on the periphery of the lower substrate 2, and the lower substrate 2 and the upper substrate 11 are overlaid so that the transparent electrodes face each other. This sealing material 16 is for bonding the upper substrate 11 and the lower substrate 2, and an epoxy resin adhesive or the like is selected and formed by a method such as screen printing. Thereafter, the stacked upper and lower substrates 11 and 2 are set on a curing jig, and the sealing material 16 is baked and cured by applying pressure and heating for a predetermined time. The height after pressure curing of the sealing material 16 is set to be smaller than that in the prior art, and the thickness f of the sealing agent 16 after firing is 5 to 8 μm, which is slightly smaller than that in the prior art. Further, the width of the sealing material 16 is reduced from about 1.5 to 2 mm to about 0.8 to 1.5 mm so that the sealing material 16 is easily bent within a range that does not impair the function of the touch panel.

  FIG. 3 shows a state where the upper and lower substrates 20 a obtained by superposing the upper substrate 11 and the lower substrate 2 are set on the curing jig 30. As shown in FIG. 3, the stacked upper and lower substrates 20 a are made into one set, and 5 to 7 sets of upper and lower substrates 20 a are stacked through a frame-shaped interleaving paper 22 having a window portion 23 and set on the curing jig 30. . Next, the upper and lower substrates 20 a are pressurized and heated at a pressure of 0.2 to 0.25 kg / cm 2 and a temperature of 150 ° C., held for 60 to 90 minutes, and the sealing material 16 is fired. The shape of the above-mentioned interleaf paper 22 is a frame-like shape having a window portion 23 as shown in FIG. 4, and the outer shape is set to be approximately the same size as the upper substrate 11. Further, the inner shape of the window portion 23 of the interleaf paper 22 is a square shape smaller than the inner shape of the seal material 16 after firing, and each side 16 a inside the seal material 16 and each side 16 a inside the seal material 16. The value of the dimensional difference t with respect to each side 23a of the window portion 23 of the interleaf paper 22 corresponding to is set in the range of 0.4 to 0.6 mm. Further, the interleaf paper 22 is not particularly limited, but in the present embodiment, high-quality paper having a thickness of 100 μm is used.

  Thereafter, by slowly cooling, the peripheral portion of the upper substrate 11 and the lower substrate 2 is adhered with the sealing material 16 to obtain the touch panel 20 as shown in FIG. On the upper substrate 11 of the touch panel 20, a concave curved portion 14 is formed in a region along the inner periphery of the sealing material 16, and the gap between the upper substrate 11 and the lower substrate 2 in the concave curved portion 14 is the thickness of the sealing material. It is slightly smaller than the value of thickness f (5 to 8 μm). Further, the vicinity of the center of the upper substrate 11 is curved in a convex shape toward the outside, and the gap between the upper substrate 11 and the lower substrate 2 near the center is slightly larger than the thickness of the sealing material. In this way, the upper substrate 11 curved into the special shape described above is obtained by using the frame-shaped interleaf paper 22 having the window portion 23.

  FIG. 2A is a partially enlarged cross-sectional view showing the vicinity of the sealing material 16 of the touch panel 20. As shown in FIG. 2 (a), the touch panel in this embodiment sets the value of the height h of the dot spacer 15 and the routing electrode 18a to approximately 2 to 4 μm, which is smaller than the conventional value, The value of the distance n with respect to the dot spacer 15 closest to the routing electrode is set to be about 10 mm, which is slightly wider than the conventional one. Further, while the thickness f of the sealing material is set in a range of 5 to 8 μm, the concave curved portion 14 is separated by a distance La in the direction of the dot spacer 15 closest to the routing wiring 18a. When the position is the lowest point D, the value of the gap g between the upper substrate 11 and the lower substrate 2 at the lowest point D is set in the range of 1.5 to 2 μm. The value of the distance La is preferably about ½ of the value of the distance n with the dot spacer 15 closest to the routing electrode. In this embodiment, the value of the distance La is 5 mm. At the lowest point D of the concave curved portion 14, the value of the gap g between the upper substrate 11 and the lower substrate 2 is as narrow as 1.5 to 2 μm, so that the upper substrate 11 and the lower substrate 2 are applied with an appropriate pressing load. Can be easily brought into contact with each other. Therefore, if the lowest point D is used as an input point for inputting data, non-contact failure can be prevented, the input point and the contact point coincide, and the linearity error can be reduced. Therefore, an effective input area can be formed up to a portion about 5 mm inside from the routing wiring 18a. The concave curved portion 14 has been described by taking the vicinity of the routing electrode 18a as an example, but the same applies to the other concave curved portions 14 formed along the inner periphery of the sealing agent 16. Thus, since an input possible area can be secured also in the peripheral portion of the upper substrate 11, the effective input area s can be widened as shown in FIG.

  Further, as shown in FIG. 2B, the upper substrate 11 is formed in such a shape that the vicinity of the center of the upper substrate 11 is curved outward, and the gap k between the upper substrate 11 and the lower substrate 2 in the vicinity of the center. The value is set in the range of 8 to 10 μm. By forming such a curved shape on the upper substrate 11, the pressing load of the entire effective input area can be made uniform, and excellent operability can be obtained.

  As described above, according to the manufacturing method of the touch panel in the present embodiment, 5-7 sets of the upper and lower substrates 11 that are overlapped are stacked through the frame-shaped interleaving paper 22 and set on the curing jig 30. By pressing and heating, the upper substrate 11 and the lower substrate 2 are adhered to each other with the sealing material 16, thereby forming a concave curved portion 14 in a region along the inner periphery of the sealing material 16 of the upper substrate 11. The center part of 11 can be formed in a convex curved shape. Accordingly, the touch panel 20 according to the present embodiment has an effective input area up to a portion about 5 mm inside from the lead-out wiring 18a even when an upper substrate made of a glass material having a thickness of 0.4 mm that is large and difficult to bend is used. And the contact between the upper and lower substrates 11 and 2 can be facilitated. As a result, it is possible to realize a touch panel that has excellent impact resistance and can secure a wide effective input area and has excellent operability.

  In general, Newton rings are likely to occur when the distance between the dot spacers and the routing wiring and the pitch between the dot spacers are increased, but the plate thickness in this embodiment is 0.4 mm and is made of a glass material that is not easily bent. When the upper substrate is used, it is confirmed that there is little problem with Newton rings and there is almost no problem.

  In the present embodiment, an example in which a glass material having a thickness of 0.4 mm is used as the material of the upper substrate has been described. However, the thickness of the plate is not limited to this, and for example, a rigidity such as 0.3 mm is used. It can also be applied to the case of a glass material that is large and difficult to bend.

  In addition, as for the interleaving paper, a high-quality paper having a thickness of 100 μm has been described as an example. However, the present invention is not limited to this, and the same effect can be obtained when the thickness is different or when other paper is used. I can do it.

The touch panel in this embodiment of this invention is shown, Fig.1 (a) is a top view, FIG.1 (b) is XX sectional drawing in Fig.1 (a). FIG. 2A is a partial enlarged cross-sectional view of a touch panel according to an embodiment of the present invention, FIG. 2A is a cross-sectional view of a B portion in FIG. 1B, and FIG. 2B is a cross-sectional view of a C portion in FIG. It is. It is a figure for demonstrating the manufacturing process of the touchscreen in embodiment of this invention. FIG. 4A is a plan view and FIG. 4B is a cross-sectional view taken along the line DD in FIG. 4A, illustrating an interleaf used in the touch panel manufacturing process according to the embodiment of the present invention. FIG. 5A shows a conventional touch panel, FIG. 5A is a plan view, and FIG. 5B is an XX cross-sectional view in FIG. It is sectional drawing of the touchscreen of a prior art. It is a partial expanded sectional view which shows the state which pressed the upper board | substrate in the touchscreen of a prior art. It is a partial expanded sectional view which shows the state which pressed the upper board | substrate in the touchscreen of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Upper substrate 2 Lower substrate 3 Transparent electrode 4 Transparent electrode 5 Dot spacer 6 Sealing material 7a, 7b Leading electrode 8a, 8b Leading electrode 9 Connector 10 Touch panel 11 Upper substrate 14 Concave curved part 15 Dot spacer 16 Sealing material 16a Inside sealant Sides 18a, 18b Lead-out electrode 20 Touch panel 20a Stacked upper and lower substrates 22 Frame-like interleaf paper 23 Interleaf window portion 23a Window portion side 30 Curing jig

Claims (9)

An upper substrate and a lower substrate on which a pair of transparent electrodes are arranged are arranged to face each other through a seal material having a predetermined thickness so that the transparent electrode surfaces face each other, and are connected to the transparent electrodes of the respective substrates. In the touch panel having electrodes and dot spacers provided in a matrix on the transparent electrode of the lower substrate,
The upper substrate is made of a glass material having a thickness of 0.3 to 0.4 mm, and has a concave curved portion in a region along the inner periphery of the sealing material of the upper substrate, and the upper substrate and the lower substrate in the concave curved portion, The touch panel is characterized in that the gap is set slightly smaller than the thickness of the sealing material.   The touch panel according to claim 1, wherein a value of a minimum gap between the upper substrate and the lower substrate in the concave curved portion is set in a range of 1.5 to 2 μm.   The touch panel according to claim 1, wherein the upper substrate has a shape in which the vicinity of the center is curved in a convex shape toward the outside.   The touch panel according to claim 3, wherein a value of a gap between the upper substrate and the lower substrate in the vicinity of the center of the upper substrate is set in a range of 8 to 10 µm.   The touch panel according to any one of claims 1 to 4, wherein a distance between the routing electrode and a dot spacer closest to the routing electrode is set in a range of 5 to 10 mm.   The touch panel according to any one of claims 1 to 5, wherein the lead-out electrode and the dot spacer are formed to have substantially the same height in a range of 2 to 4 µm.   The touch panel according to any one of claims 1 to 6, wherein a pitch of the dot spacers is set in a range of 5 to 6 mm.   The thickness of the said sealing material is set to the range of 5-8 micrometers, The touch panel of any one of Claims 1-7 characterized by the above-mentioned.   In the method of manufacturing a touch panel, the upper substrate and the lower substrate on which a pair of transparent electrodes are disposed are overlapped with a sealant so that the transparent electrode surfaces face each other, and the upper substrate and the lower substrate are adhered to each other. A set of upper and lower substrates on which the substrate and the lower substrate are overlapped, and a plurality of sets of upper and lower substrates are laminated through a frame-shaped interleaving paper having a window portion, and are pressed and heated for a predetermined time. It has a step of baking the sealing agent to adhere the upper substrate and the lower substrate, the inner shape of the window portion of the interleaf paper is a rectangular shape smaller than the inner shape of the sealing material after firing, By setting the difference between each side on the inner side of the sealing material and each side of the window corresponding to each side on the inner side of the sealing material to a range of 0.4 to 0.6 mm, the sealing material for the upper substrate Forming a concave curved portion in a region along the inner circumference, and an upper substrate in the concave curved portion; Method for producing a touch panel, and forming a slightly smaller gap than the thickness of the sealing material to the substrate.

Images