Touch sensor stack structure and manufacturing method thereof

Abstract

According to an exemplary embodiment of the present invention, a touch sensor stack structure and a method for manufacturing the touch sensor stack structure are provided. The touch sensor stack structure includes: a touch sensor structure including a bonding portion; a circuit connection structure bonded to the bonding portion of the touch sensor structure; and an optical film stacked on the touch sensor structure. The optical film includes a protrusion that covers an end portion of the circuit connection structure and overlaps the bonding portion. The optical film can prevent damage to the electrodes included in the touch sensor structure.

Description

[0001] Cross-reference to related applications and priority claim

[0002] This application claims the benefit of Korean Patent Application No. 10-2020-0031938 filed on March 16, 2020 in the Korean Intellectual Property Office (KIPO), the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The present invention relates to a touch sensor stack structure and a manufacturing method thereof. More specifically, the present invention relates to a touch sensor stack structure including a touch sensor layer and an optical layer and a manufacturing method thereof. Background Art

[0004] With the development of information technology, various demands are increasing for display devices having thinner size, light weight, high power consumption efficiency, etc. The display device may include a flat panel display device such as a liquid crystal display (LCD) device, a plasma display panel (PDP) device, an electroluminescent display device, an organic light emitting diode (OLED) display device, etc.

[0005] A touch panel or touch sensor capable of inputting a user's instructions by selecting an instruction displayed on a screen with a finger or an input tool has also been developed. The touch panel or touch sensor may be combined with a display device, thereby realizing display and information input functions in one electronic device.

[0006] For example, the touch panel may include a sensing electrode and a pad for applying a signal to the sensing electrode. The pad may be electrically connected to a circuit member to which a driving signal may be applied. In addition, an optical film of a display device (such as a polarizing plate) may be laminated on the touch panel.

[0007] Therefore, the touch panel, the circuit member, and the optical film may be manufactured as one module or laminate, and may require precise interlayer alignment, a cutting process, etc. In addition, electrodes included in the touch panel may be damaged due to a lamination process or bending of the laminate.

[0008] For example, as disclosed in Korean Registration Patent Publication No. 10-2078385, various image display devices combined with a touch screen panel have been recently developed. However, processing configurations in optical film lamination, circuit member bonding, and the like are not suggested. Summary of the invention

[0009] According to an aspect of the present invention, a touch sensor stack structure with improved mechanical stability and reliability is provided.

[0010] According to one aspect of the present invention, a method of manufacturing a touch sensor stack structure with improved mechanical stability and reliability is provided.

[0011] The above aspects of the inventive concept are achieved through the following features or configurations:

[0012] (1) A touch sensor stacking structure, comprising: a touch sensor structure, the touch sensor structure including a bonding portion; a circuit connection structure, the circuit connection structure bonded to the bonding portion of the touch sensor structure; and an optical film stacked on the touch sensor structure, wherein the optical film includes a protrusion, the protrusion covers an end portion of the circuit connection structure and overlaps with the bonding portion.

[0013] (2) The touch sensor stack structure according to (1) above, wherein the protrusion of the optical film includes a wing portion protruding from a lateral side of the bonding portion in a plan view.

[0014] (3) The touch sensor stack structure according to (1) above, wherein a width of the wing portion is 0.1 μm to about 50 μm.

[0015] (4) A touch sensor stack structure according to (1) above, wherein the touch sensor structure includes: a substrate layer; a sensing electrode, the sensing electrode being arranged on the substrate layer; and a pad portion, the pad portion being gathered in the bonding portion and electrically connected to the sensing electrode.

[0016] (5) The touch sensor stack structure according to (4) above, wherein the circuit connection structure is electrically connected to the pad portion and includes a flexible printed circuit board.

[0017] (6) The touch sensor stack structure according to (1) above, wherein the optical film includes a polarizing plate.

[0018] (7) A touch sensor stacking structure according to (1) above, wherein the joining portion protrudes from one side of the touch sensor structure, and the protrusion extends from one side of the optical film, wherein the width of the protrusion of the optical film is greater than the width of the joining portion of the touch sensor structure.

[0019] (8) A method for manufacturing a touch sensor stack structure, comprising: preparing a touch sensor structure; partially removing an end portion of the touch sensor structure through a first cutting process to form a joining portion; joining a circuit connection structure to the joining portion; forming an optical film on the touch sensor structure to cover the end portion of the circuit connection structure; and cutting the touch sensor structure and the optical film around the joining portion through a second cutting process.

[0020] (9) The method according to (8) above, wherein the first cutting process includes forming an alignment key at a corner portion of the touch sensor structure.

[0021] (10) The method according to (9) above, wherein the second cutting process includes aligning the cutting tool with reference to the alignment key.

[0022] (11) The method according to (9) above, wherein the second cutting process includes cutting the corner portion where the alignment key is formed.

[0023] (12) The method according to (8) above, wherein the end portion of the touch sensor structure includes a bonding area and edge areas adjacent to both sides of the bonding area, and the first cutting process includes cutting the edge area.

[0024] (13) A window stack structure includes: a touch sensor stack structure according to the embodiment described above; and a window substrate, the window substrate being disposed on the touch sensor stack structure.

[0025] (14) According to the window stack structure described in (13) above, the optical film of the touch sensor stack structure includes a polarizing plate, and the optical film is arranged between the window substrate and the touch sensor structure.

[0026] (15) An image display device includes: a display panel; and a touch sensor stack structure according to the above-described embodiment, the touch sensor stack structure being stacked on the display panel.

[0027] According to an embodiment of the present invention, a first cutting process for cutting the peripheral portion of the bonding area around the touch sensor structure may be performed, and then the circuit connection structure may be bonded. Later, an optical film such as a polarizing plate may be laminated, and the peripheral portion of the touch sensor structure and the optical film around the bonding area may be cut by a second cutting process. Electrode cracks occurring at the edge portion of the touch sensor layer may be prevented, and cutting stress may be distributed by sequentially repeating the cutting process.

[0028] In some embodiments, an alignment key may be formed on the touch sensor layer together with the first cutting process. The alignment key may be used to improve the accuracy and reliability of the second cutting process.

[0029] In some embodiments, the cut portion of the optical film obtained by the second cutting process may include a stepped portion or a wing portion protruding from the cut portion of the touch sensor layer. The wing portion may serve as an electrode protection pattern for the touch sensor layer, so that electrode cracks and electrode corrosion at the edge portion of the touch sensor structure may be prevented. In addition, the bending stress in the bonding area may be reduced by the wing portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figures 1 to 5 is a schematic top plan view illustrating a method of manufacturing a touch sensor stack structure according to an exemplary embodiment.

[0031] Figure 6 is a partially enlarged top plan view showing a cut portion surrounding a bonding portion of a touch sensor stack structure according to an exemplary embodiment.

[0032] Figure 7 2 is a schematic cross-sectional view illustrating a window stack structure and an image display device according to an exemplary embodiment. DETAILED DESCRIPTION

[0033] According to an exemplary embodiment of the present invention, a touch sensor stacking structure is provided, the touch sensor stacking structure including an optical film and a circuit connection structure. According to an exemplary embodiment of the present invention, a method for manufacturing a touch sensor structure is also provided, the method including a lamination process and a cutting process of the optical film.

[0034] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. However, those skilled in the art will appreciate that such embodiments described with reference to the accompanying drawings are provided to further understand the spirit of the present invention, rather than to limit the subject matter to be protected as disclosed in the specific embodiments and the appended claims.

[0035] Figures 1 to 5 is a schematic top plan view illustrating a method of manufacturing a touch sensor stack structure according to an exemplary embodiment.

[0036] refer to Figure 1 , a touch sensor structure 100 may be prepared. The touch sensor structure 100 may include sensing electrodes 110 and 120 disposed on a substrate layer 105 .

[0037] The substrate layer 105 may include a flexible and transparent insulating material. For example, the substrate layer 105 may include a resin material such as cycloolefin polymer (COP), polyethylene terephthalate (PET), polyacrylate (PAR), polyetherimide (PEI), polyethylene naphthalate (PEN), polyphenylene sulfide (PPS), polyallyl ester, polyimide (PI), cellulose acetate propionate (CAP), polyether sulfone (PES), triacetyl cellulose (TAC), polycarbonate (PC), cycloolefin copolymer (COC), polymethyl methacrylate (PMMA), etc. The substrate layer 105 may include an inorganic insulating material such as glass, silicon oxide, etc.

[0038] The substrate layer 105 may include an active area AA, a bonding area BA, and an edge area MA. The active area AA may include a central portion of the substrate layer 105, and may be an area that may substantially recognize a user's touch and may generate a signal.

[0039] For example, when a user's touch is input onto the active area AA, a change in capacitance may occur due to the sensing electrodes 110 and 120. Thus, the physical touch may be converted into an electrical signal to implement touch sensing.

[0040] The sensing electrodes 110 and 120 may include a first sensing electrode 110 and a second sensing electrode 120 .

[0041] The first sensing electrodes 110 may be arranged along the length direction or column direction of, for example, the substrate layer 105 or the touch sensor stack structure. Therefore, a first sensing electrode row may be formed by a plurality of first sensing electrodes 110. Alternatively, a plurality of first sensing electrode columns may be arranged in a width direction or a row direction.

[0042] In some embodiments, first sensing electrodes 110 adjacent in the column direction may be physically or electrically connected to each other through connection portions 115. For example, connection portions 115 may be integrally formed with first sensing electrodes 110 at the same level.

[0043] The second sensing electrodes 120 may be arranged along the row direction or the width direction. In some embodiments, the second sensing electrodes 120 may be physically separated from each other as island-type unit electrodes. In this case, the second sensing electrodes 120 adjacent in the row direction may be electrically connected to each other through the bridge electrode 125.

[0044] The plurality of second sensing electrodes 120 may be connected to each other in the first direction through the bridge electrode 125 so that a second sensing electrode row may be formed. The plurality of second sensing electrode rows may be arranged along a column direction or a length direction.

[0045] The sensing electrodes 110 and 120 and / or the bridge electrode 125 may each include: silver (Ag), gold (Au), copper (Cu), aluminum (Al), platinum (Pt), palladium (Pd), chromium (Cr), titanium (Ti), tungsten (W), niobium (Nb), tantalum (Ta), vanadium (V), iron (Fe), manganese (Mn), cobalt (Co), nickel (Ni), zinc (Zn), molybdenum (Mo), calcium (Ca), or an alloy containing at least one of the metals (e.g., silver palladium copper (APC), copper calcium (CuCa)). These may be used alone or in combination. For example, the sensing electrodes 110 and 120 may have a mesh structure including a metal or an alloy.

[0046] The sensing electrodes 110 and 120 and the bridging electrode 125 may each include a transparent conductive material. For example, the sensing electrodes 110 and 120 and the bridging electrode 125 may include a transparent conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium zinc tin oxide (IZTO), and cadmium tin oxide (CTO), silver nanowires (AgNW), carbon nanotubes (CNT), graphene, conductive polymers, etc.

[0047] In some embodiments, the sensing electrodes 110 and 120 may include a stacked structure of a transparent conductive oxide layer and a metal layer. For example, the sensing electrodes 110 and 120 may include a double-layer structure of a transparent conductive oxide layer-metal layer or a triple-layer structure of a transparent conductive oxide layer-metal layer-transparent conductive oxide layer. In this case, the flexibility characteristics can be improved by the metal layer, and the signal transmission speed can also be improved by the low resistance of the metal layer. The transparent conductive oxide layer can improve corrosion resistance and transparency.

[0048] In some embodiments, the bridging electrode 125 may be formed on an insulating layer (not shown). The insulating layer may at least partially cover the connection portion 115 included in the first sensing electrode 110, and may at least partially cover the second sensing electrode 120 surrounding the connection portion 115. The bridging electrode 125 may be formed through the insulating layer and may be electrically connected to the second sensing electrodes 120 adjacent to each other, with the connection portion 115 interposed therebetween.

[0049] The insulating layer may include an inorganic insulating material such as silicon oxide or silicon nitride, or an organic insulating material such as acrylic resin or siloxane resin.

[0050] The trace 130 may diverge and extend from each of the first sensing electrode column and the second sensing electrode row. The trace 130 may diverge from an end portion of each of the first sensing electrode column and the second sensing electrode row, and may extend over a peripheral area surrounding the active area AA.

[0051] The trace 130 may extend in the length direction toward the bonding area BA allocated to a portion of one end of the touch sensor structure 100. Terminals of the trace 130 may be gathered on the bonding area BA of the substrate layer 105. The pad portions 140 may be formed on the bonding area BA and may be respectively connected to the trace 130. In an embodiment, the terminal of the trace 130 may be provided as the pad portion 140.

[0052] For ease of description, Figure 1 Illustration of the connection structure between the trace 130 and the pad portion 140 is omitted.

[0053] In some embodiments, the touch sensor structure 100 can be formed by a transfer process. For example, a sensing electrode layer including the sensing electrodes 110 and 120, the bridging electrode 125, and the trace 130 described above can be formed on a carrier substrate. Later, the sensing electrode layer can be transferred to the substrate layer 105, and the carrier substrate can be peeled off and removed to obtain the touch sensor structure 100.

[0054] In an implementation, a separation layer including an organic material for facilitating a lift-off process may be formed between the sensing electrode layer and the carrier substrate.The sensing electrode layer and the substrate layer 105 may be bonded to each other by an adhesive layer.

[0055] like Figure 1 As shown, the edge area MA may be included at one end of the substrate layer 105 or the touch sensor structure 100 in the length direction. For example, areas adjacent to both sides of the bonding area BA may be allocated as the edge area MA.

[0056] Hereinafter, illustration of a detailed electrode arrangement included in the touch sensor structure 100 is omitted for convenience of description.

[0057] refer to Figure 2 , a first cutting process can be performed on the touch sensor structure 100 .

[0058] In an exemplary embodiment, Figure 1 The edge area MA of the illustrated touch sensor structure 100 may be at least partially removed by the first cutting process. The bonding area BA may at least partially remain by the first cutting process so that the bonding portion 150 may be formed.

[0059] The bonding portion 150 may include the pad portion 140 and may serve as a bonding tag for the bonding process with the circuit connection structure, as will be described below. Figure 2 As shown, the engagement portion 150 may have a generally trapezoidal shape in plan view.

[0060] As described above, the edge area MA may be at least partially removed by the first cutting process so that the recess 160 may be formed at one end of the touch sensor structure 100 or the substrate layer 105. For example, two recesses 160 may be formed with the bonding portion 150 interposed therebetween.

[0061] In an exemplary embodiment, the alignment key 170 may be formed during the first cutting process together with the recess 160. In some embodiments, the alignment key 170 may be formed at a corner portion of one end of the touch sensor structure 100 or the substrate layer 105.

[0062] For example, the alignment key 170 may be formed on Figure 2 The alignment key 170 may be formed at two corner portions of an upper portion of the touch sensor structure 100. The alignment key 170 may have a hole shape.

[0063] refer to Figure 3 , the circuit connection structure 180 may be bonded to the bonding portion 150 .

[0064] In an exemplary embodiment, the circuit connection structure 180 may include a flexible printed circuit board (FPCB).For example, the circuit connection structure 180 may include a core layer and a circuit wiring formed on the core layer.

[0065] For example, the circuit connection structure 180 may be aligned on the bonding portion 150 and then a thermal pressing process may be performed using a punching tool such as a soldering head so that the circuit wiring of the circuit connection structure 180 and the pad portion 140 included in the bonding portion 150 may be electrically connected to each other.

[0066] In some embodiments, the conductive intermediate film 185 may be disposed between the collection portion 150 and the circuit connection structure 180, and then a bonding process may be performed by compressing the bonding portion 150 and the circuit connection structure 180 toward each other. For example, the conductive intermediate film 185 may include an anisotropic conductive film (ACF).

[0067] According to the above exemplary embodiment, the bonding process can be performed in a state where the recess 160 is formed in the touch sensor structure 100 by the first cutting process. Therefore, damage to the trace 130 included in the touch sensor structure 100 caused when stress generated by heat / pressure from the bonding process is transferred to the substrate layer 105 can be prevented.

[0068] refer to Figure 4 , the optical film 200 may be laminated on the touch sensor structure 100 .

[0069] In an exemplary embodiment, the optical film 200 may include a film or layer structure known in the art for improving the image visibility of an image display device. Non-limiting examples of the optical film 200 may include a polarizing plate, a polarizer, a retardation film, a reflective sheet, a brightness enhancement film, a refractive index matching film. These may be used alone or in a multilayer structure including two or more thereof.

[0070] In an embodiment, the optical film 200 may be a polarizing plate. In this case, the optical film 200 may include, for example, a polyvinyl alcohol-based polarizer and a protective film formed on at least one surface of the polarizer. The protective film may include, for example, a resin material such as triacetyl cellulose (TAC) and cycloolefin polymer (COP).

[0071] In some embodiments, the optical film 200 may partially cover the bonding portion 150 and partially cover the end portion of the circuit connection structure 180. The optical film 200 may partially cover the end portion of the recess 160.

[0072] refer to Figure 5 , the optical film 200 and the touch sensor structure 100 may be cut together through a second cutting process.

[0073] In an exemplary embodiment, the end portions of the touch sensor structure 100 and the optical film 200 adjacent to the circuit connection structure 180 and the bonding portion 150 may be cut and removed by the second cutting process. Therefore, the touch sensor structure 100 and the optical film 200 may substantially share the same cutting surface around the bonding portion 150.

[0074] In some embodiments, the second cutting process can be performed using the alignment key 170 formed in the first cutting process. For example, the cutting tool used for the second cutting process can be aligned with reference to the alignment key 170. The alignment key 170 can be removed together with the corner portion of the touch sensor structure 100 by the second cutting process.

[0075] In some embodiments, the touch sensor structure 100 and two lateral portions of the optical film 200 surrounding the bonding portion 150 may be cut through the second cutting process. Therefore, the recess 160 included in the touch sensor structure 100 may also be removed through the second cutting process.

[0076] In an exemplary embodiment, the protrusion 210 may be formed at the end portion of the optical film 200 through the second cutting process. The protrusion 210 may partially overlap the coupling portion 150 and may cover the end portion of the circuit connection structure 180.

[0077] The protrusion 210 may be formed of the optical film 200 so that the circuit connection structure 180 may be more stably fixed to the joint portion 150. For example, the circuit connection structure 180 may be bent downward to be connected to the main board of the image display device. In this case, the circuit connection structure 180 may be bent together with the joint portion 150.

[0078] The bonding portion 150 having a reduced width can be formed by the touch sensor structure 100 through the first and second cutting processes as described above, so that bending can be performed more easily. In addition, when bending is performed using the protrusion 210 of the optical film 200, the circuit connection structure 180 can be prevented from being separated, and cracks and delamination of the pad portion 140 can also be prevented.

[0079] Additionally, the pad portion 140 may be covered by the protrusion 210 of the optical film 200 , so that corrosion of the pad portion 140 may be substantially suppressed or reduced.

[0080] Figure 6 is a partially enlarged top plan view showing a cut portion around a bonding portion of a touch sensor stack structure according to an exemplary embodiment.

[0081] refer to Figure 6 As described above, the optical film 200 may include the protrusion 210 partially covering the bonding portion 150 and the circuit connection structure 180. In an exemplary embodiment, the width of the protrusion 210 may be greater than the width of the bonding portion 150 of the touch sensor structure 100.

[0082] Therefore, the protrusion 210 may include a wing portion 220 protruding from the lateral surface of the bonding portion 150 in the width direction. The wing portion 220 may serve as a cover layer that protects the lateral surface of the bonding portion 150 included in the touch sensor structure 100. Therefore, corrosion of the pad portion 140 caused by moisture and air penetrating the lateral surface of the bonding portion 150 may be additionally prevented.

[0083] In an embodiment, the width D of the wing portion 220 may be from about 0.1 μm to about 50 μm. When the width of the wing portion 220 exceeds about 50 μm, the step difference between the touch sensor structure 100 and the optical film 200 may excessively increase to cause mechanical defects.

[0084] Figure 7 2 is a schematic cross-sectional view illustrating a window stack structure and an image display device according to an exemplary embodiment.

[0085] refer to Figure 7 , the window stack structure 300 may include the window substrate 350 and the touch sensor stack structure 320 according to the exemplary embodiment as described above.

[0086] The window substrate 350 may include, for example, a hard coating film, thin glass (eg, ultra-thin glass (UTG)). In an embodiment, a light shielding pattern 340 may be formed on a peripheral portion of a surface of the window substrate 340. The light shielding pattern 340 may include a color-printed pattern and may have a single-layer or multi-layer structure.

[0087] A bezel portion or a non-display area of ​​the image display device may be defined by the light shielding pattern 340. The light shielding pattern 340 may function as a decorative film or a decorative pattern.

[0088] The touch sensor stack structure 320 may be combined with the window substrate 350 as a film or a panel. In an implementation, the touch sensor stack structure 320 may be combined with the window substrate 350 via the first adhesive layer 330.

[0089] For example, the window substrate 350, the optical film 200 of the touch sensor stack structure 320, and the touch sensor structure 100 of the touch sensor stack structure 320 may be placed in sequence from the viewer's perspective. In this case, the sensing electrode of the touch sensor structure 200 may be disposed below the optical film including the polarizing layer or the polarizing plate, so that the viewer may be effectively prevented from recognizing the electrode pattern.

[0090] The image display device may include a display panel 400 and a window stack structure 300 including a touch sensor stack structure 320 according to an exemplary embodiment.

[0091] The display panel 400 may include a pixel electrode 410 , a pixel defining layer 420 , a display layer 430 , an opposite electrode 440 , and an encapsulation layer 450 disposed on a panel substrate 405 .

[0092] The panel substrate 405 may include a flexible resin material. In this case, the image display device may be provided as a flexible display.

[0093] A pixel circuit including a thin film transistor (TFT) may be formed on the panel substrate 405, and an insulating layer covering the pixel circuit may be formed. The pixel electrode 410 may be electrically connected to, for example, a drain electrode of the TFT on the insulating layer.

[0094] The pixel defining layer 420 may be formed on the insulating layer, and the pixel electrode 410 may be exposed through the pixel defining layer 420 so that a pixel region may be defined. The display layer 430 may be formed on the pixel electrode 410, and the display layer 430 may include, for example, a liquid crystal layer or an organic light emitting layer.

[0095] The opposite electrode 440 may be disposed on the pixel defining layer 420 and the display layer 430. The opposite electrode 440 may function as, for example, a common electrode or a cathode of the image display device. An encapsulation layer 450 may be disposed on the opposite electrode 440 to protect the display panel 400.

[0096] In some embodiments, the display panel 400 and the touch sensor stacking structure 320 may be combined with each other by the second adhesive layer 310. For example, the thickness of the second adhesive layer 310 may be greater than the thickness of the first adhesive layer 330. At a temperature in the range of -20°C to 80°C, the viscoelasticity of the second adhesive layer 310 may be about 0.2 MPa or less. In this case, the noise from the display panel 400 may be blocked, and the interfacial stress during bending may be alleviated, so that damage to the window stacking structure 300 may be avoided. In an embodiment, the viscoelasticity of the second adhesive layer 310 may be in the range of about 0.01 MPa to about 0.15 MPa.

Claims

1. A touch sensor stack structure, comprising: a touch sensor structure, the touch sensor structure comprising a bonding portion; a circuit connection structure bonded to the bonding portion of the touch sensor structure; as well as an optical film stacked on the touch sensor structure, wherein the optical film includes at least one or more of a polarizing plate, a retardation film, a reflective sheet, a brightness enhancement film, and a refractive index matching film, the optical film includes a protrusion, the protrusion covers an end portion of the circuit connection structure and overlaps the bonding portion, and the protrusion is formed on a top surface of the circuit connection structure, wherein the engaging portion protrudes from one side of the touch sensor structure, and the protrusion extends from one side of the optical film, wherein the protrusion of the optical film includes a wing portion protruding from a lateral side of the engaging portion in a plan view, Wherein, a width of the protruding portion of the optical film is greater than a width of the joining portion of the touch sensor structure. 2 . The touch sensor stack structure according to claim 1 , wherein a width of the wing portion is 0.1 μm to 50 μm.

3. The touch sensor stack structure according to claim 1, wherein the touch sensor structure comprises: substrate layer; A sensing electrode, wherein the sensing electrode is arranged on the substrate layer; as well as A pad portion is gathered in the bonding portion and is electrically connected to the sensing electrode. 4 . The touch sensor stack structure of claim 3 , wherein the circuit connection structure is electrically connected to the pad portion and comprises a flexible printed circuit board. The touch sensor stack structure of claim 1 , wherein the optical film comprises a polarizing plate.

6. A method for manufacturing a touch sensor stack structure, comprising: preparing a touch sensor structure; partially removing an end portion of the touch sensor structure through a first cutting process to form a bonding portion; joining a circuit connection structure to the joining portion; forming an optical film on the touch sensor structure to cover an end portion of the circuit connection structure; as well as cutting the touch sensor structure and the portion of the optical film surrounding the joining portion by a second cutting process, wherein, through the second cutting process, a protrusion is formed by the optical film on the top surface of the circuit connection structure, and the protrusion includes a wing portion protruding from a lateral side of the bonding portion in a plan view. 7 . The method of claim 6 , wherein the first cutting process includes forming an alignment key at a corner portion of the touch sensor structure.

8. The method of claim 7, wherein the second cutting process includes aligning a cutting tool with reference to the alignment key. 9 . The method of claim 7 , wherein the second cutting process includes cutting the corner portion where the alignment key is formed.

10. The method of claim 6, wherein the end portion of the touch sensor structure includes a bonding area and edge areas adjacent to both sides of the bonding area, and The first cutting process includes cutting the edge area.

11. A window stacking structure, comprising: The touch sensor stack structure according to claim 1; as well as A window substrate is disposed on the touch sensor stacking structure.

12. The window stack structure according to claim 11, wherein the optical film of the touch sensor stack structure comprises a polarizing plate, and The optical film is disposed between the window substrate and the touch sensor structure.

13. An image display device, comprising: Display panel; as well as The touch sensor stack structure according to claim 1, wherein the touch sensor stack structure is stacked on the display panel.

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