KR102435351B1 - Touch sensor module, window stack structure including the same and image display device including the same - Google Patents

Abstract

The touch sensor module of the embodiments of the present invention includes a touch sensor layer including sensing electrodes and traces branching from the sensing electrodes, a flexible circuit board electrically connected to the traces at one end of the touch sensor layer, and the A support structure that partially covers the flexible circuit board and the touch sensor layer in common, an optical layer disposed on a central portion of the touch sensor layer and spaced apart from the support structure in a horizontal direction to form a gap, and at least partially covering the gap a filling layer filled with It is possible to prevent damage and peeling of electrodes and wires included in the flexible circuit board and the touch sensor layer by the support structure and the filling layer.

Description

A touch sensor module, a window laminate including the same, and an image display device including the same

The present invention relates to a touch sensor module, a window laminate including the same, and an image display device including the same. More particularly, it relates to a touch sensor module including a sensing electrode and an insulating structure, and a window laminate and an image display device including the same.

With the recent development of information technology, demands for the display field are also presented in various forms. For example, various flat panel display devices with characteristics such as thinness, light weight, and low power consumption, for example, a liquid crystal display device, a plasma display panel device, Electroluminescent display devices, organic light-emitting diode display devices, and the like are being studied.

On the other hand, a touch panel or a touch sensor, which is an input device that is attached to the display device and allows a user to input a command by selecting instructions displayed on the screen with a human hand or an object, is combined with the display device to provide an image display function and Electronic devices in which an information input function is implemented are being developed.

In addition, a flexible display having the flexibility to be folded or bent has recently been developed, and accordingly, the touch sensor needs to be developed to have appropriate properties, design, and structure to be applied to the flexible display as well. In addition, it is necessary to arrange and design the touch sensor in consideration of the reliability of the connection to the main board, the circuit board, etc. included in the image display device.

For example, as in Korean Patent Application Laid-Open No. 2014-0092366, a touch sensor or a touch screen panel coupled to various image display devices has recently been developed.

Korean Patent Publication No. 2014-0092366

One object of the present invention is to provide a touch sensor module having improved electrical and mechanical reliability.

One object of the present invention is to provide a window laminate including a touch sensor module having improved electrical and mechanical reliability.

An object of the present invention is to provide an image display device including a touch sensor module having improved electrical and mechanical reliability.

1. A touch sensor layer including sensing electrodes and traces branching from the sensing electrodes; a flexible circuit board electrically connected to the traces at one end of the touch sensor layer; a support structure that partially covers the flexible circuit board and the touch sensor layer in common; an optical layer disposed on a central portion of the touch sensor layer and spaced apart from the support structure in a horizontal direction to form a gap; and a filling layer that at least partially fills the gap.

2. The touch sensor module according to 1 above, wherein the filling layer has a lower upper surface than the optical layer and the supporting structure.

3. The touch sensor module according to 1 above, wherein the filling layer partially covers the upper surface of the support structure and has a lower upper surface than the optical layer.

4. The touch sensor module according to 1 above, wherein the peeling layer has a viscosity of 1000 to 5000 cP at room temperature.

5. The method of 1 above, wherein the peeling layer has a tensile modulus of 5 to 3500 MPa, a touch sensor module.

6. The touch sensor module according to the above 1, wherein the adhesive force of the peeling layer to the surface of the touch sensor layer is 2 N/25mm or more.

7. The touch sensor module of 1 above, wherein the touch sensor layer includes a display area in which the sensing electrodes are disposed, a trace area in which the traces are disposed, and a connection area in which distal ends of the traces are disposed.

8. The above 7, wherein the flexible circuit board is electrically connected to the distal ends of the trace in the connection region,

The support structure covers the connection area and the trace area in a planar direction, the touch sensor module.

9. The touch sensor module according to 8 above, wherein the support structure overlaps some of the sensing electrodes in the planar direction.

10. The touch sensor module according to 9 above, wherein the touch sensor layer further includes a margin area in which the partial sensing electrodes are arranged between the display area and the trace area.

11. The touch sensor module according to 10 above, wherein the filling layer covers the remaining portion of the margin area.

12. The method of 1 above, wherein the optical layer comprises at least one of a polarizer, a polarizing plate, a retardation film, a reflective sheet, a brightness enhancement film, or a refractive index matching film, a touch sensor module.

13. The above 1, wherein the support structure is a base layer; and a support layer that is formed on the base layer and includes an adhesive material, and is in contact with the flexible circuit board and the touch sensor layer.

14. The touch sensor module according to 1 above, wherein the peeling layer includes an adhesive resin.

15. Window substrate; and a touch sensor module according to any one of claims 1 to 14 laminated on one surface of the window substrate.

16. Display panel; and a touch sensor module stacked on the display panel according to any one of 1 to 14 above.

17. The method of 16 above, further comprising a main board disposed below the touch sensor module, wherein a portion of the touch sensor layer of the touch sensor module and the flexible circuit board are bent together with the support structure to form a main board An electrically connected, image display device.

The touch sensor module according to embodiments of the present invention may include a support structure that partially covers the touch sensor layer and the flexible printed circuit board together. When the touch sensor module is folded or bent by the support structure, peeling of the flexible printed circuit board may be prevented, and damage to the sensing electrode or trace in the bending area may be prevented.

In some embodiments, the touch sensor module may further include an optical film disposed on the touch sensor layer. A gap may be formed between the support structure and the optical film, and a filling layer filling the gap may be formed. Adhesion or adhesion of the support structure may be further improved by the peeling layer, and damage to the sensing electrode or trace may be additionally suppressed when the protective film under the touch sensor layer is peeled off.

The touch sensor module is made of, for example, a thin film of a substrate-less type, and can be effectively applied to an image display device such as a flexible display.

1 is a cross-sectional view showing a schematic structure of a touch sensor module according to example embodiments.
2 is a cross-sectional view showing a schematic structure of a touch sensor module according to some exemplary embodiments.
3 and 4 are plan views illustrating a schematic structure of a touch sensor layer according to example embodiments.
5 is a schematic diagram illustrating a window laminate and an image display device according to example embodiments.
6 is a schematic cross-sectional view illustrating an image display device coupled with a touch sensor module according to example embodiments.

Embodiments of the present invention include a touch sensor layer, an optical layer and a flexible circuit board respectively disposed on the display area and the peripheral area of the touch sensor layer, and further include adhesive structures, so that mechanical and electrical stability is improved A touch sensor module is provided.

In addition, embodiments of the present invention provide a window laminate and an image display device including the touch sensor module.

Hereinafter, with reference to the drawings, embodiments of the present invention will be described in more detail. However, the following drawings attached to the present specification illustrate preferred embodiments of the present invention, and serve to further understand the technical spirit of the present invention together with the above-described content of the present invention, so the present invention is described in such drawings It should not be construed as being limited only to the matters.

In the following drawings, for example, parallel to the upper surface of the protective film or the touch sensor layer and for example, two directions perpendicular to each other are defined as a first direction and a second direction. For example, the first direction may correspond to a length direction of the touch sensor module, and the second direction may correspond to a width direction of the touch sensor module. In addition, a direction perpendicular to the first and second directions is defined as a third direction. For example, the third direction may correspond to a thickness direction of the touch sensor module.

1 is a cross-sectional view showing a schematic structure of a touch sensor module according to example embodiments.

Referring to FIG. 1 , the touch sensor module includes a touch sensor layer 100 , an optical layer 150 and a flexible circuit board 160 disposed on the touch sensor layer 100 , a flexible circuit board 160 , and a touch sensor. a support structure 170 partially covering the layer 100 together, and a filling layer 165 formed between the optical layer 150 and the support structure 170 .

In some embodiments, the touch sensor layer 100 may be disposed on the protective film 50 . The protective film 50 may include, for example, an inorganic insulating film and/or an organic insulating film. For example, cyclic olefin polymer (COP), polyethylene terephthalate (PET), polyacrylate (PAR), polyetherimide (PEI), polyethylene naphthalate (PEN), polyphenylene sulfide (PPS), polyallylate (polyallylate), polyimide (PI), cellulose acetate propionate (CAP), polyethersulfone (PES), cellulose triacetate (TAC), polycarbonate (PC), cyclic olefin copolymer (COC), polymethyl meta A polymer film including acrylate (PMMA) or the like may be used as the protective film 50 .

In one embodiment, the protective film 50 is formed to protect sensing electrodes, traces, etc. during the manufacturing process of the touch sensor layer 100 , and may be removed after forming the touch sensor module.

The touch sensor layer 100 may include conductive patterns such as the sensing electrode and the trace, and may further include an insulating layer for mutually insulating the conductive patterns. The configuration and structure of the touch sensor layer 100 will be described later in more detail with reference to FIGS. 3 and 4 .

A flexible printed circuit board (FPCB) 160 may be disposed on one end of the touch sensor layer 100 and may be electrically connected to traces included in the touch sensor layer 100 . In one embodiment, the terminal or pad portion formed at the end of the trace and the circuit wiring included in the flexible circuit board 160 are formed by a conductive intermediary structure such as an anisotropic conductive film (ACF). may be electrically connected to each other.

The flexible circuit board 160 may include, for example, a core layer including a resin or liquid crystal polymer and the circuit wiring printed on the core layer. In addition, a coverlay layer covering the circuit wiring may be further included on the core layer. A part of the coverlay layer may be removed to expose a portion of the circuit wiring connected to the terminal part or the pad part of the touch sensor layer 100 .

The touch sensor layer 100 may further include a passivation layer protecting the sensing electrode and traces. In this case, the passivation layer portion formed in the connection region connected to the flexible circuit board 160 may be removed.

The support structure 170 may be formed on portions of the flexible circuit board 160 and the touch sensor layer 100 disposed on the connection area. Accordingly, the support structure 170 may commonly or partially cover ends of the touch sensor layer 100 and the flexible circuit board 160 .

The support structure 170 is a protective pattern that prevents damage such as peeling or cracking of the sensing electrode or trace that occurs during peeling, folding, or bending of the flexible circuit board 160 caused by external stress in the connection region. can be provided. In addition, mechanical damage can be reduced or prevented by holding the flexible circuit board 160 and/or the touch sensor layer 100 when the protective film 50 is removed by the support structure 170 as described above.

The support structure 170 may have a multi-layer structure. For example, the support structure 170 may include a base layer 172 and a support layer 174 formed on the surface of the base layer 172 . The support layer 174 includes, for example, an acrylic-based, silicone-based, urethane-based and/or rubber-based adhesive material, and ends of the flexible circuit board 160 and the touch sensor layer 100 in the connection region. It can be held by contact with them.

The base layer 172 may include, for example, a polymer material as described above in the protective film 50 .

The touch sensor module may further include an optical layer 150 . The optical layer 150 may include a film or layer structure known in the art for improving image visibility of an image display device. Non-limiting examples of the optical layer 150 include a polarizing plate, a polarizer, a retardation film, a reflective sheet, a brightness enhancing film, a refractive index matching film, and the like. These may be included alone or as two or more multilayer structures.

According to exemplary embodiments, the optical layer 150 may be positioned on the same layer or on the same level as the support structure 170 . In some embodiments, the optical layer 150 and the support structure 170 may be horizontally spaced apart by a predetermined distance. Accordingly, a gap 155 may be formed between the optical layer 150 and the support structure 170 . The gap 155 may serve as a margin region for alignment of the support structure 170 .

According to example embodiments, a filling layer 165 filling the gap 155 may be formed. The filling layer 165 at least partially fills the gap 155 , and may be in contact with the top surface of the touch sensor layer 100 and sidewalls of the optical layer 150 and the support structure 170 .

In some embodiments, the peeling layer 165 may be formed to have an upper surface lower than the upper surface of each of the optical layer 150 and the touch sensor layer 100 .

The peeling layer 165 may be formed by filling the adhesive resin composition in the gap 155 and then curing it through room temperature curing, thermal curing, or ultraviolet curing process. The resin composition may include an acryl-based, silicone-based, urethane-based and/or rubber-based resin. In one embodiment, the resin composition may further include a solvent, a photopolymerizable monomer, a polymerization initiator, a curing agent, and the like.

As described above, during the attachment process of the support structure 170 , an alignment margin may be first secured through the gap 155 in order to prevent contact with the optical layer 150 . Thereafter, the filling layer 165 may be formed by filling the gap 155 by separately filling the resin composition. Accordingly, an exposed area of the touch sensor layer 100 is reduced by the peeling layer 165 , so that the protective effect of the sensing electrode may be further improved. In addition, as the peeling layer 165 contacts and holds the sidewalls of the optical layer 150 and the support structure 170 , even when the protective film 50 is quickly peeled off and removed, the support structure 170 and the optical Peeling and lifting of the layer 150 can be suppressed. In addition, it is possible to significantly reduce the occurrence of cracks in the sensing electrode during the peeling process of the protective film 50 .

In some embodiments, the viscosity of the peeling layer 165 may be about 1000 to 5000 cP at room temperature (25° C.), preferably about 1000 to 4000 cP. While the filling layer 165 substantially fills the inside of the gap 155 within the above viscosity range, outflow of the resin material may be prevented.

In some embodiments, the tensile modulus of the peeling layer 165 may be about 5 to 3500 MPa, preferably about 1000 to 3500 MPa. Damage to the sensing electrode in the bending region of the touch sensor module may be effectively suppressed within the range of the tensile modulus of elasticity.

In some embodiments, the adhesion of the peeling layer 165 to the bonding surface of the touch sensor layer 100 may be about 2 N/25 mm or more, preferably about 5 N/25 mm or more. In this case, when the touch sensor module is bent, electrode peeling of the peeling layer 165 and the touch sensor layer 100 can be sufficiently suppressed.

The thickness of the peeling layer 165 may be adjusted in a range that can satisfy the aforementioned viscosity, tensile modulus, and adhesion, for example, in a range of about 20 to 100 μm.

In some embodiments, an adhesive layer for bonding the optical layer 150 may be further formed on the upper surface of the touch sensor layer 100 . In some embodiments, an adhesive layer may be formed between the protective film 50 and the touch sensor layer 100 .

2 is a cross-sectional view showing a schematic structure of a touch sensor module according to some exemplary embodiments. Detailed description of the configuration and/or structure described with reference to FIG. 1 will be omitted.

Referring to FIG. 2 , the filling layer 165 may fill the gap 155 and partially cover the upper surface of the support structure 170 together. Accordingly, the support structure 170 may be more stably fixed during the bending of the flexible circuit board 160 and/or the peeling of the protective film 50 .

The upper surface of the filling layer 165 may be formed lower than the optical layer 150 . Accordingly, the filling layer 165 is formed so as not to cover the upper surface of the optical layer 150 , and it is possible to prevent the characteristics of the optical layer 150 from being disturbed by the filling layer 165 .

3 and 4 are plan views illustrating a schematic structure of a touch sensor layer according to example embodiments.

Referring to FIG. 3 , the touch sensor layer may include sensing electrodes 110 and 120 and traces 130 and 135 . According to exemplary embodiments, the sensing electrodes 110 and 120 may be arranged to be driven by a mutual capacitance method.

The touch sensor layer may include a display area D, a trace area T, and a connection area P. The display area D may include a central area of the touch sensor layer, and may be an area in which an image of an image display device to which the touch sensor module is applied is implemented to a user.

The connection region P is disposed at one end of the touch sensor layer in the first direction, and may be a region in which electrical connection with the flexible circuit board 160 is implemented. As shown in FIG. 3 , the display area D, the trace area T, and the connection area P may be sequentially disposed along the first direction. In some embodiments, a margin area M may be disposed between the display area D and the trace area T.

The sensing electrodes 110 and 120 may be arranged in the display area D of the touch sensor layer. According to example embodiments, the sensing electrodes 110 and 120 may include first sensing electrodes 110 and second sensing electrodes 120 .

The first sensing electrodes 110 may be arranged, for example, in the second direction (eg, a width direction). Accordingly, a first sensing electrode row extending in the second direction may be formed by the plurality of first sensing electrodes 110 . Also, a plurality of rows of the first sensing electrode may be arranged in the first direction.

In some embodiments, the first sensing electrodes 110 adjacent in the second direction may be physically or electrically connected to each other by the connection part 115 . For example, the connection part 115 may be integrally formed at the same level as the first sensing electrodes 110 .

The second sensing electrodes 120 may be arranged along the first direction (eg, a longitudinal direction). In some embodiments, the second sensing electrodes 120 may be physically spaced apart from each other as island-type unit electrodes. In this case, the second sensing electrodes 120 adjacent in the first direction may be electrically connected to each other by the bridge electrode 125 .

As the plurality of second sensing electrodes 120 are connected to each other by the bridge electrodes 125 and arranged in the first direction, a second sensing electrode column extending in the first direction may be formed. Also, the plurality of second sensing electrode columns may be arranged along the second direction.

The sensing electrodes 110 and 120 and/or the bridge electrode 125 may include a metal, an alloy, or a transparent conductive oxide.

For example, the sensing electrodes 110 and 120 and/or the bridge electrode 125 may include silver (Ag), gold (Au), copper (Cu), aluminum (Al), platinum (Pt), or palladium (Pd). , chromium (Cr), titanium (Ti), tungsten (W), niobium (Nb), tantalum (Ta), vanadium (V), iron (Fe), manganese (Mn), cobalt (Co), nickel (Ni) , zinc (Zn), tin (Sn), or an alloy thereof (eg, silver-palladium-copper (APC)). These may be used alone or in combination of two or more.

The sensing electrodes 110 and 120 and/or the bridge electrode 125 are, for example, indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium zinc tin oxide (IZTO), and cadmium. A transparent conductive oxide such as tin oxide (CTO) may be included.

In some embodiments, the sensing electrodes 110 and 120 and/or the bridge electrode 125 may include a stacked structure of a transparent conductive oxide and a metal. For example, the sensing electrodes 110 and 120 and/or the bridge electrode 125 may have a three-layer structure of a transparent conductive oxide layer, a metal layer, and a transparent conductive oxide layer. In this case, while the flexible characteristic is improved by the metal layer, the signal transmission speed may be improved by lowering the resistance, and corrosion resistance and transparency may be improved by the transparent conductive oxide layer.

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

The insulating layer may include an inorganic insulating material such as silicon oxide or silicon nitride, or an organic insulating material such as an acrylic resin or a siloxane-based resin.

Traces 130 and 135 may include a first trace 130 extending from each of the first sensing electrode rows and a second trace 135 extending from each of the second sensing electrode columns.

As shown in FIG. 3 , the traces 130 and 135 may extend from the periphery of the display area D to be aggregated into the trace area T. As shown in FIG.

For example, the first traces 130 may branch from each first sensing electrode row from both sides of the touch sensor layer and extend in the first direction. The first traces 130 may be bent while entering the trace region T to extend in the second direction. The first traces 130 may be bent again in the first direction to extend from the connection area P in the first direction.

In some embodiments, the first traces 130 may be alternately distributed on both sides of the touch sensor layer. Since the first traces 130 are evenly distributed on both sides of the touch sensor layer, stress generated when bending is applied, which will be described later, can be uniformly distributed. In addition, since the first traces 130 are alternately disposed on both sides of the first traces 130 , it is possible to increase the alignment margin between the adjacent first traces 130 .

The second traces 135 may be branched from each second sensing electrode column and extend in the second direction in the trace region T. Thereafter, it may be bent again in the first direction to extend to the connection area P in the first direction.

The distal ends of the traces 130 and 135 may be assembled in the connection region P to provide a connection portion electrically connected to the flexible circuit board 160 . A first connection part 140 and a second connection part 145 may be defined from the first trace 130 and the second trace 135 , respectively, and may be disposed in the connection area P area.

The traces 130 and 135 may include a conductive material substantially the same as or similar to that of the sensing electrodes 110 and 120 .

According to example embodiments, the flexible circuit board 160 may be electrically connected to the connection parts 140 and 145 on the connection region P. In some embodiments, a conductive intermediary structure such as an anisotropic conductive film (ACF) may be disposed between the flexible circuit board 160 and the connection parts 140 and 145 .

In example embodiments, the support structure 170 may cover the connection region P and the trace region T together in a planar direction. The bonding force between the flexible circuit board 160 and the touch sensor layer 100 is increased by the support structure 170 , so that the flexible circuit board 160 and/or traces in a subsequent process such as a peeling process of the protective film 50 . It is possible to prevent mechanical defects such as dropping off (130, 135).

In some embodiments, a margin area M may be further included between the display area D and the trace area T. The margin region M may be a region where bending or folding of the touch sensor module starts. Also, the margin area M may be provided as a buffer area for transmission of a touch signal through the sensing electrodes 120 and 110 between the display area D and the trace area T.

In example embodiments, the support structure 170 may partially cover the margin region M such that a gap 155 is formed, as shown in FIG. 1 . In this case, the support structure 170 may also partially overlap the sensing electrodes 110 and 120 in the planar direction. The optical layer 150 illustrated in FIG. 1 may entirely cover the display area D in a planar direction.

The filling layer 165 illustrated in FIGS. 1 and 2 may fill the remaining portion of the margin region M, for example.

As the support structure 170 is disposed to cover a portion of the sensing electrodes 110 and 120 on the margin region M, when folding or bending occurs in the margin region M, breakage or separation of the sensing electrodes 110 and 120 Mechanical defects such as these can be suppressed. In addition, as the filling layer 165 fills the remaining portion of the margin region M, process stability of the sensing electrodes 110 and 120 may be further improved.

Referring to FIG. 4 , the sensing electrodes 127 and the traces 137 of the touch sensor layer may be arranged to be driven in a self-capacitance manner.

The touch sensor layer may include sensing electrodes 127 provided in independent island patterns, respectively. In addition, the traces 137 may be branched to each sensing electrode 127 and extend to the trace region T. As shown in FIG. Distal ends of the traces 137 may be assembled in the connection region P to be electrically connected to the flexible circuit board 160 .

As described above, the support structure 170 may cover the touch sensor layer and the flexible circuit board 160 together on the trace area T and the connection area P. In addition, it may extend onto the margin region M to cover some of the sensing electrodes 127 , and the remaining portion of the margin region M may be filled by the filling layer 165 as described above.

5 is a schematic diagram illustrating a window laminate and an image display device according to example embodiments.

The window stack 190 may include the window substrate 180 and the touch sensor module according to the above-described exemplary embodiments. The touch sensor module may include, for example, the touch sensor layer 100 described with reference to FIGS. 3 to 4 and the optical layer 150 stacked on the display area D of the touch sensor layer 100 . have. In FIG. 5 , the support structure 170 and the flexible circuit board 160 are not shown in FIG. 5 , and will be described in more detail with reference to FIG. 6 .

The window substrate 180 includes, for example, a hard coating film, and in an embodiment, a light blocking pattern 185 may be formed on a periphery of one surface of the window substrate 180 . The light blocking pattern 185 may include, for example, a color printing pattern, and may have a single-layer or multi-layer structure. A bezel portion or a non-display area of the image display device may be defined by the light blocking pattern 185 .

The optical layer 150 may include various optical films or optical structures included in the image display device, and may include a coated polarizer or a polarizing plate in some embodiments. The coating-type polarizer may include a liquid crystal coating layer including a polymerizable liquid crystal compound and a dichroic dye. In this case, the optical layer 150 may further include an alignment layer for imparting alignment to the liquid crystal coating layer.

For example, the polarizing plate may include a polyvinyl alcohol-based polarizer and a protective film attached to at least one surface of the polyvinyl alcohol-based polarizer.

The optical layer 150 may be directly bonded to the one surface of the window substrate 180 or may be attached through the first adhesive layer 60 .

The touch sensor layer 100 may be included in the window laminate 190 in the form of a film or panel. In an embodiment, the touch sensor layer 100 may be coupled to the optical layer 150 through the second adhesive layer 70 .

As shown in FIG. 5 , the window substrate 180 , the optical layer 150 , and the touch sensor layer 100 may be disposed in order from the user's viewing side. In this case, since the sensing electrodes of the touch sensor layer 100 are disposed under the optical layer 150 including a polarizer or a polarizing plate, a pattern recognition phenomenon can be more effectively prevented.

In an embodiment, the window substrate 180 , the touch sensor layer 100 , and the optical layer 150 may be disposed in order from the user's viewing side.

The image display device may include the display panel 200 and the window stack 190 coupled to the display panel 200 and including the touch sensor module according to example embodiments.

The display panel 200 may include a pixel electrode 210 , a pixel defining layer 220 , a display layer 230 , a counter electrode 240 , and an encapsulation layer 250 disposed on a panel substrate 205 . can

The panel substrate 205 may include a flexible resin material, and in this case, the image display device may be provided as a flexible display.

A pixel circuit including a thin film transistor (TFT) may be formed on the panel substrate 205 , and an insulating layer covering the pixel circuit may be formed. The pixel electrode 210 may be electrically connected to, for example, a drain electrode of a TFT on the insulating layer.

The pixel defining layer 220 may be formed on the insulating layer to expose the pixel electrode 210 to define a pixel area. A display layer 230 is formed on the pixel electrode 210 , and the display layer 230 may include, for example, a liquid crystal layer or an organic light emitting layer.

The counter electrode 240 may be disposed on the pixel defining layer 220 and the display layer 230 . The counter electrode 240 may be provided, for example, as a common electrode or a cathode of the image display device. An encapsulation layer 250 for protecting the display panel 200 may be stacked on the opposite electrode 240 .

In some embodiments, the display panel 200 and the window stack 190 may be coupled through the adhesive layer 80 . For example, the thickness of the adhesive layer 80 may be greater than the thickness of each of the first and second adhesive layers 60 and 70, and the viscoelasticity at -20 to 80° C. may be about 0.2 MPa or less. In this case, noise from the display panel 200 may be shielded, and interfacial stress may be relieved during bending to suppress damage to the window laminate 190 . In one embodiment, the viscoelasticity may be about 0.01 to 0.15 MPa.

6 is a schematic cross-sectional view illustrating an image display device coupled with a touch sensor module according to example embodiments. For example, FIG. 6 is a view for explaining the connection of the driving circuit through the flexible circuit board of the touch sensor module.

Referring to FIG. 6 , the image display device includes a display panel 200 and a main board 300 , and may include a touch sensor module according to the above-described exemplary embodiments. The touch sensor module may include a touch sensor layer 100 and an optical layer 150 disposed on the display area D of the touch sensor layer 100 .

As described with reference to FIG. 3 or FIG. 4 , bending is started from the margin region M of the touch sensor layer 100 and the third direction (eg, the thickness direction of the image display device) along the first direction. ) can be bent. Accordingly, connection portions of the traces included in the connection region P may be electrically connected to the main board 300 through the flexible circuit board 160 . The flexible circuit board 160 may be connected to, for example, a bonding pad 350 formed on a bottom surface of the main board 300 .

In an embodiment, the distal end (eg, the connection region P and/or the trace region T) of the touch sensor module or the touch sensor layer 100 may be bent by 180 degrees ( ^o ) or more. Accordingly, the distal end may extend in the first direction again. The distal end may face the unbent portion of the touch sensor layer 100 in the third direction.

As described above, even when abrupt bending or bending is applied, the support structure 170 fixes the bonding between the flexible circuit board 160 and the touch sensor layer 100 , thereby suppressing breakage and separation of circuits, wirings, and electrodes. can do. In addition, as the filling layer 165 fills the gap included in the margin region M, mechanical damage such as cracking of the sensing electrode in the bending start region may be suppressed.

Hereinafter, experimental examples including preferred embodiments are presented to help the understanding of the present invention, but these examples only illustrate the present invention and do not limit the appended claims, and the scope and spirit of the present invention It is obvious to those skilled in the art that various changes and modifications to the embodiments are possible within the scope, and it is natural that such variations and modifications fall within the scope of the appended claims.

Example One

A touch sensor sample (manufactured by Dongwoo Finechem) including electrode patterns and traces with a thickness of 0.14 μm including ITO with a 20 μm PET protective film was prepared.

A polarizing plate to which a polyvinyl alcohol (PVA) polarizer having a thickness of 20 μm is attached on an 80 μm thick TAC protective film was attached to the center of the touch sensor layer.

The traces at the distal end of the touch sensor layer were connected to the FPCB, and a support structure was attached to cover the FPCB at the distal end of the touch sensor layer so that the separation distance from the polarizing plate was 10 μm. As the support structure, Nitto Denko's acrylic tape (product number: 360A) was cut and used.

A filling layer was formed by UV curing after filling the space between the polarizing plate and the support structure with a resin composition. The resin composition was prepared by adding 1-hydroxycyclohexylphenylketone as an acrylic copolymer and a photopolymerization initiator. The acrylic copolymer was prepared by adding n-butyl acrylate, methacrylate, benzyl methacrylate, acrylic acid and 4-hydroxybutyl acrylate and azobisisobutylonitrile as an initiator to ethyl acetate and then reacting.

The viscosity, thickness, tensile modulus, and adhesion of the peeling layer were measured separately, and the measurement results are shown in Table 1 below.

The viscosity of the peeling layer was measured at 25°C using an Anton rheometer MCR-300 using a PP-50 tip.

The tensile modulus of elasticity of the peeling layer was measured according to the method of ASTM D638 using Shimazdu's AG-X equipment.

The adhesion of the peeling layer was measured as follows. A sheet was manufactured by applying a peeling layer to a thickness of 25 μm on a PET film, bonding a release film thereon, and irradiating a UV lamp (10 mW, 1000 mJ). The produced sheet was cut to have a width of 25 mm and a length of 100 mm to prepare a peeling sheet. Then, the release film attached to the other side of the peeling layer is peeled off, and the peeling sheet is attached to the touch sensor surface using a roller of 2 kg according to the regulations of JIS Z 0237, and then autoclaved (50 ° C, 5 atmospheres) ) for about 20 minutes to prepare a sample. Then, using an autograph (AG-1S, SHIMADZU) was used to measure the adhesive force when peeling at 23°C, 50RH%, peeling angle 180°, and peeling rate 300mm/min.

Example 2 to 10

The viscosity, tensile modulus and adhesion of the peeling layer were changed as described in Table 1 below by changing the amount of UV curing of the peeling layer, the content of the acrylic copolymer and/or the content of the photopolymerization initiator.

comparative example

A touch sensor module was manufactured in the same manner as in Example 1, except that the filling layer formation was omitted.

touch sensor layer crack occurrence measurement

In the touch sensor modules of Examples and Comparative Examples, after peeling off the PET protective film attached to the bottom surface of the touch sensor layer, it was observed whether cracks in the electrode pattern or trace included in the touch sensor layer were observed.

The occurrence of cracks was observed while changing the peeling rate of the protective film, and when cracks did not occur, “○” was indicated, and when cracks were observed, it was indicated as “×”.

The evaluation results are shown together in Table 1 below.

viscosity
(cP) tensile modulus
(MPa) Touch sensor layer surface adhesion
(N/25mm) thickness
(μm) according to peeling speed
Whether touch sensor cracks occur 10m/min 20m/min 30m/min Example 1 1500 1500 6.5 50 ○ ○ ○ Example 2 1500 1500 6.5 50 ○ ○ ○ Example 3 1500 1500 6.5 50 ○ ○ ○ Example 4 2200 2500 5.8 50 ○ ○ ○ Example 5 3000 1800 6.7 50 ○ ○ ○ Example 6 3600 1000 7.1 50 ○ ○ ○ Example 7 1500 1500 7.2 60 ○ ○ ○ Example 8 1500 1500 8.1 80 ○ ○ ○ Example 9 300 3800 0.7 10 ○ × × Example 10 500 1100 1.1 20 ○ × × Example 11 5500 2000 7.6 150 ○ ○ × comparative example - - - - × × ×

Referring to Table 1, in the case of the comparative example in which the peeling layer was omitted, cracks occurred in the electrode of the touch sensor layer when the protective film was peeled off. On the other hand, in the case of Examples 9 to 11 in which the viscosity of the filling layer was too low or high, some electrode cracks were observed while the peeling rate was increased.

50: protective film 100: touch sensor layer
110: first sensing electrode 115: connection part
120: second sensing electrode 125: bridge electrode
127: sensing electrode 130: first trace
135: second trace 137: trace
140: first connection 145: second connection
150: optical layer 155: gap
160: flexible circuit board 165: filling layer
170: support structure 172: base layer
174: support layer

Claims (17)

a touch sensor layer including sensing electrodes and traces branching from the sensing electrodes;
a flexible circuit board electrically connected to the traces at one end of the touch sensor layer;
a support structure that partially covers upper surfaces of the flexible circuit board and the touch sensor layer;
an optical layer disposed on a central portion of the touch sensor layer and spaced apart from the support structure in a horizontal direction to form a gap; and
a filling layer that at least partially fills the gap;
The filling layer is in contact with the upper surface of the touch sensor layer, the sidewall of the optical layer, and the sidewall of the support structure, the touch sensor module.
The touch sensor module of claim 1 , wherein the peeling layer has a lower upper surface than the optical layer and the support structure.
The touch sensor module of claim 1 , wherein the peeling layer partially covers an upper surface of the support structure, and has a lower upper surface than the optical layer.
The touch sensor module of claim 1, wherein the peeling layer has a viscosity of 1000 to 5000 cP at room temperature.
The method according to claim 1, The tensile modulus of elasticity of the peeling layer is 5 to 3500 MPa, the touch sensor module.
The method according to claim 1, Adhesive force of the peeling layer to the surface of the touch sensor layer is 2 N/25mm or more, the touch sensor module.
The touch sensor module of claim 1 , wherein the touch sensor layer includes a display area in which the sensing electrodes are disposed, a trace area in which the traces are disposed, and a connection area in which distal ends of the traces are disposed.
The method according to claim 7, wherein the flexible circuit board is electrically connected to the distal ends of the trace in the connection region,
The support structure covers the connection area and the trace area in a planar direction, the touch sensor module.
The touch sensor module of claim 8 , wherein the support structure overlaps some of the sensing electrodes in the planar direction.
The touch sensor module of claim 9 , wherein the touch sensor layer further comprises a margin area in which the partial sensing electrodes are arranged between the display area and the trace area.
The touch sensor module of claim 10 , wherein the filling layer covers the remainder of the margin area.
The method according to claim 1, wherein the optical layer comprises at least one of a polarizer, a polarizing plate, a retardation film, a reflective sheet, a brightness enhancement film, or a refractive index matching film, the touch sensor module.
The method according to claim 1, The support structure is a base layer; and a support layer that is formed on the base layer and includes an adhesive material, and is in contact with the flexible circuit board and the touch sensor layer.
The touch sensor module of claim 1 , wherein the peeling layer comprises an adhesive resin.
window substrate; and
A window laminate comprising the touch sensor module according to any one of claims 1 to 14 laminated on one surface of the window substrate.
display panel; and
An image display device stacked on the display panel and including the touch sensor module according to any one of claims 1 to 14.
The method according to claim 16, further comprising a main board disposed below the touch sensor module,
A portion of the touch sensor layer of the touch sensor module and the flexible circuit board are bent together with the support structure to be electrically connected to the main board.

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