Curved screen display module and terminal device

Abstract

A curved screen display module (10) and a terminal device. An adhesive material layer (3) is provided on one side of a display panel (1). A cover plate (4) is provided on the surface of the side of the adhesive material layer (3) distant from the display panel (1). The adhesive material layer (3) comprises a first adhesive layer (31) and a second adhesive layer (32). The second adhesive layer (32) is in surface contact with at least part of the cover plate (4). The 180-degree peel strength of the second adhesive layer (32) is greater than that of the first adhesive layer (31), and / or the cohesion of the first adhesive layer (31) is greater than that of the second adhesive layer (32).

Description

Curved screen display modules and terminal devices

[0001] This application claims priority to Chinese patent application No. 202410345674.9 filed on March 25, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present application relates to the field of display technology, and in particular to a curved screen display module and terminal device. Background Art

[0003] Deeply curved display panels are increasingly popular with consumers, and the trend for future deeply curved products is towards greater and steeper curvatures. The edge curvature of current curved screen phones is becoming increasingly steeper, with increasingly steeper and deeper curves. This increases the module's rebound force at greater curvatures. Current module structures and colloid materials are no longer able to meet the demands of this high-specification four-curve design, as the bending rebound force exceeds the viscosity of the current colloid material. As shown in Figure 1, open bubbles originate at the edge of the adhesive layer and grow through rebound. After lamination, these bubbles can form around the curved surface at all four corners, causing defects such as rebound bubbles. These rebound bubbles can occur at the interface between the colloid material and the cover plate, as well as closed bubbles within the colloid material due to cohesive failure, leading to colloid material failure.

[0004] Therefore, the existing curved screen display module has a technical problem that many bubbles at the edge of the glue material layer cause the glue material to fail, and an improvement solution is urgently needed to solve it. SUMMARY OF THE INVENTION

[0005] The embodiments of the present application provide a curved screen display module and a terminal device, which can alleviate the technical problem of failure of existing curved screen display modules caused by numerous bubbles in the adhesive material layer.

[0006] On the one hand, an embodiment of the present application provides a curved screen display module, comprising:

[0007] Display panel;

[0008] an adhesive material layer, the adhesive material layer being disposed on one side of the display panel;

[0009] a cover plate, the cover plate being disposed on a surface of the adhesive material layer that is away from the display panel;

[0010] In which, the adhesive material layer includes at least a first adhesive layer and a second adhesive layer, the first adhesive layer is arranged in surface contact with the polarizer, the second adhesive layer is arranged in surface contact with at least a partial area of ​​the cover plate, the 180-degree peel force of the second adhesive layer is set to be greater than the 180-degree peel force of the first adhesive layer, and / or the cohesive force of the first adhesive layer is set to be greater than the cohesive force of the second adhesive layer.

[0011] On the other hand, an embodiment of the present application provides a terminal device, which includes the curved screen display module described in any of the above embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0013] FIG1 is a schematic diagram of rebound bubbles in a curved screen display module provided by the present application;

[0014] FIG2 is a schematic diagram of the first structure of the curved screen display module provided by the present application;

[0015] FIG3 is a schematic diagram of a second structure of a curved screen display module provided by the present application;

[0016] FIG4 is a first schematic top view of the curved screen display module provided by the present application;

[0017] FIG5 is a schematic cross-sectional view of the curved screen display module provided in FIG4 of the present application at section AA;

[0018] FIG6 is a second schematic top view of the curved screen display module provided by the present application;

[0019] FIG7 is a schematic cross-sectional view of the curved area of ​​the curved screen display module provided in FIG6 of the present application.

[0020] Description of reference numerals:

[0021] Modes for Carrying Out the Invention

[0022] The technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings in the embodiments of the present application. The technical solutions described below are only used to explain and illustrate the ideas of the present application and should not be regarded as limiting the scope of protection of the present application. In this application, the various embodiments can be combined with each other but will not be described one by one in detail.

[0023] In addition, the terms "first", "second" and similar words do not indicate any order, quantity or importance, but are only used to distinguish different technical features. The term "plurality" and similar words mean two or more, unless otherwise expressly limited.

[0024] An embodiment of the present application provides a curved screen display module, comprising:

[0025] Display panel;

[0026] an adhesive material layer, the adhesive material layer being disposed on one side of the display panel;

[0027] a cover plate, the cover plate being disposed on a surface of the adhesive material layer that is away from the display panel;

[0028] In which, the adhesive material layer includes at least a first adhesive layer and a second adhesive layer, the first adhesive layer is arranged in surface contact with the polarizer, the second adhesive layer is arranged in surface contact with at least a partial area of ​​the cover plate, the 180-degree peel force of the second adhesive layer is set to be greater than the 180-degree peel force of the first adhesive layer, and / or the cohesive force of the first adhesive layer is set to be greater than the cohesive force of the second adhesive layer.

[0029] Optionally, in some embodiments of the present application, the thickness of the second adhesive layer is smaller than the thickness of the first adhesive layer.

[0030] Optionally, in some embodiments of the present application, the thickness of the first adhesive layer is d1, and the thickness of the second adhesive layer is d2, wherein 15 micrometers ≤ d2 ≤ 75 micrometers, and d1 + d2 ≤ 200 micrometers.

[0031] Optionally, in some embodiments of the present application, the curved screen display module includes a straight edge area and a curved area located between adjacent straight edge areas, wherein, in the curved area, the edge of the second adhesive layer is set beyond the edge of the display panel, and the edge of the second adhesive layer is located on the inner side of the edge of the cover plate.

[0032] Optionally, in some embodiments of the present application, in the straight edge area, the edge of the display panel is arranged beyond the edge of the adhesive material layer.

[0033] Optionally, in some embodiments of the present application, in the curved area, an edge of the first adhesive layer is flush with an edge of the display panel.

[0034] Optionally, in some embodiments of the present application, the adhesive material layer further includes a third adhesive layer, the third adhesive layer is arranged between the first adhesive layer and the second adhesive layer, and the cohesive force of the third adhesive layer is greater than the cohesive force of the second adhesive layer.

[0035] Optionally, in some embodiments of the present application, the bonding strength between the second adhesive layer and the cover plate is greater than the bonding strength between the first adhesive layer and the polarizer, and the bonding strength between the second adhesive layer and the cover plate is greater than the bonding strength between the third adhesive layer and the first adhesive layer.

[0036] Optionally, in some embodiments of the present application, the first adhesive layer is made of any one of hot melt adhesive and UV curing adhesive, and the second adhesive layer is made of any one of solvent adhesive and non-UV curing adhesive.

[0037] An embodiment of the present application provides a terminal device, which includes the curved screen display module described in any of the above embodiments.

[0038] Beneficial effect: The adhesive material layer is divided into at least two layers, so that the 180-degree peeling force of the second adhesive layer in contact with the cover plate is greater, thereby improving the bonding strength between the adhesive material layer and the cover plate and reducing the generation of open bubbles. Alternatively, the cohesive force of the first adhesive layer arranged away from the cover plate is greater, reducing the generation of closed bubbles in the adhesive material layer, thereby reducing bubbles and avoiding failure of the adhesive material layer, alleviating the technical problem of failure of the existing curved screen display module due to excessive bubbles in the adhesive material layer.

[0039] The embodiments of the present application provide a curved screen display module and a terminal device, which are described in detail below. It should be noted that the description order of the following embodiments does not limit the preferred order of the embodiments.

[0040] Referring to Figure 2 , the curved screen display module 10 provided in this application includes a display panel 1, an adhesive material layer 3, and a cover plate 4. The cover plate 4 is disposed on a surface of the polarizer 2 that is away from the display panel 1, and the adhesive material layer 3 is located between the display panel 1 and the cover plate 4. The adhesive material layer 3 includes a first adhesive layer 31 and a second adhesive layer 32. The second adhesive layer 32 is disposed in surface contact with the cover plate 4 over at least a portion of its surface. The 180-degree peel strength of the second adhesive layer 32 is greater than the 180-degree peel strength of the first adhesive layer 31, and / or the cohesive force of the first adhesive layer 31 is greater than the cohesive force of the second adhesive layer 32.

[0041] In one or more embodiments, by dividing the adhesive material layer 3 into at least two layers, the 180-degree peeling force of the second adhesive layer 32 in contact with the cover plate 4 is greater, thereby improving the bonding strength between the adhesive material layer 3 and the cover plate 4 and reducing the generation of open bubbles. Alternatively, the cohesive force of the first adhesive layer 31 arranged away from the cover plate 4 is greater, reducing the generation of closed bubbles in the adhesive material layer 3, thereby reducing bubbles and avoiding failure of the adhesive material layer 3.

[0042] The technical solution of this application is now described in conjunction with specific embodiments.

[0043] The embodiments of the present application are only described by dividing the adhesive material layer 3 into two layers or three layers. The adhesive material layer 3 may be at least two layers. The present application is also applicable to other multi-layer adhesive material layers 3.

[0044] In addition, the 180-degree peeling force of the second adhesive layer 32 is greater than the 180-degree peeling force of the first adhesive layer 31 . The 180-degree peeling force in this application refers to the 180-degree peeling force obtained under the same test standard and the same measuring equipment.

[0045] In addition, the thickness range, selected materials, etc. of this application are only described as the best or better implementation methods. Other methods that can meet the inventive concept of this application should also fall within the scope of protection of the present invention and will not be repeated here.

[0046] It should be noted that the 180-degree peel strength can be obtained through a peel strength test. Specifically, the first adhesive layer is peeled off at a specified rate so that the first adhesive layer gradually separates along the length of the adhered surface. The 180-degree peel strength of the first adhesive layer refers to the performance of the first adhesive layer in resisting 180-degree peeling. The 180-degree peel strength test method of the second adhesive layer is similar to that of the first adhesive layer. The second adhesive layer is peeled off at the same specified rate, and the 180-degree peel strength of the second adhesive layer can be obtained.

[0047] It should be noted that the cohesive force of the first adhesive layer and the second adhesive layer can be obtained through a 90-degree pull-out test.

[0048] In one embodiment, the curved screen display module 10 may be a depolarizer structure.

[0049] For example, by setting a color resist and a color filter layer to replace the polarizer, the polarizer is removed to obtain a depolarizer structure.

[0050] In one embodiment, referring to Figures 3, 4, and 5, the curved screen display module 10 further includes a polarizer 2, which is disposed on one side surface of the display panel 1, and the cover plate 4 is disposed on a side surface of the polarizer 2 away from the display panel 1.

[0051] In one embodiment, the thickness of the second adhesive layer 32 is smaller than the thickness of the first adhesive layer 31 .

[0052] It can be understood that since the cohesive force of the first adhesive layer 31 is greater than the cohesive force of the second adhesive layer 32, the thicker the first adhesive layer 31 is, the greater the cohesive force of the entire adhesive material layer 3 is, and the fewer closed bubbles generated by the adhesive material layer 3 itself.

[0053] It should be noted that the bubbles in the adhesive material layer 3 include closed bubbles generated by the adhesive material layer 3 itself and open bubbles generated between the adhesive material layer 3 and the cover plate 4 , wherein the open bubbles are generated at the edge of the second adhesive layer 32 in the curved area 8 .

[0054] In this embodiment, by increasing the thickness of the first adhesive layer 31 , the overall cohesive strength of the adhesive material layer 3 can be enhanced, thereby reducing closed bubbles and further preventing the adhesive material layer 3 from failing.

[0055] In one embodiment, the thickness of the first adhesive layer 31 is d1, and the thickness of the second adhesive layer 32 is d2, wherein 15 micrometers ≤ d2 ≤ 75 micrometers, and d1 + d2 ≤ 200 micrometers.

[0056] The thickness d2 of the second adhesive layer 32 can be 15 micrometers, 30 micrometers, 45 micrometers, 60 micrometers, or 75 micrometers.

[0057] The value of d1+d2 may be 90 microns, 130 microns, 160 microns, or 200 microns.

[0058] It can be understood that the second adhesive layer 32 is in surface contact with the cover plate 4. When the second adhesive layer 32 is greater than 15 microns, the bonding performance between the second adhesive layer 32 and the cover plate 4 can be met. When the thickness of the second adhesive layer 32 is smaller, when the thickness of the adhesive material layer 3 is constant, the thickness of the first adhesive layer 31 is greater, thereby making the overall cohesion of the adhesive material layer 3 stronger, thereby reducing the generation of closed bubbles.

[0059] It can be understood that when the thickness of the adhesive material layer 3 is constant, the smaller the thickness of the second adhesive layer 32 is, the stronger the cohesion of the adhesive material layer 3 is and the fewer the number of closed bubbles is; when the thickness of the second adhesive layer 32 is constant, the greater the thickness of the adhesive material layer 3 is, the stronger the cohesion of the adhesive material layer 3 is and the fewer the number of closed bubbles is.

[0060] In this embodiment, by limiting the thickness of the adhesive material layer 3 and the thickness of the second adhesive layer 32, the cohesive force of the adhesive material layer 3 can be further adjusted, thereby further reducing the number of closed bubbles and avoiding failure of the adhesive material layer 3 while ensuring the bonding strength between the cover plate 4 and the adhesive material layer 3.

[0061] In one embodiment, referring to FIG. 6 , the curved screen display module 10 includes a curved area 8 and a straight edge area 9 located between adjacent curved areas 8 , wherein, within the curved area 8 , the edge of the second adhesive layer 32 is arranged beyond the edge of the display panel 1 , and the edge of the second adhesive layer 32 is located on the inner side of the edge of the cover plate 4 .

[0062] Please refer to FIG. 6 , the curved area 8 is located at the four corners of the curved screen display module 10 .

[0063] Please refer to FIG. 6 , the straight edge area 9 is a straight edge setting position between adjacent corner positions.

[0064] It can be understood that since open bubbles are only generated at the edge of the second adhesive layer 32 in the curved area 8, by expanding the second adhesive layer 32 in the curved area 8 and setting the edge of the second adhesive layer 32 outside the edge of the display panel 1, the path for bubbles generated at the edge of the second adhesive layer 32 to be transmitted to the interior is lengthened, thereby further preventing failure of the adhesive material layer 3.

[0065] In this embodiment, by expanding the second adhesive layer 32 in the curved area 8 relative to the display panel 1, the path for the bubbles generated at the edge of the second adhesive layer 32 in the curved area 8 to be transmitted inward is lengthened, thereby reducing the impact of the open bubbles on the failure of the adhesive material layer 3, thereby avoiding the failure of the adhesive material layer 3.

[0066] In one embodiment, referring to FIG. 6 and FIG. 7 , when the curved area of ​​the curved screen display module is curved, the adhesive material layer is arranged as shown in FIG. 7 .

[0067] In one embodiment, in the straight edge area 9 , the edge of the display panel 1 is disposed beyond the edge of the adhesive material layer 3 .

[0068] It can be understood that the straight edge of the adhesive material layer 3 between the adjacent curved areas 8 is designed to be indented. Since the adhesive material layer 3 between the adjacent curved areas 8 almost does not produce open bubbles, the adhesive material layer 3 between the adjacent curved areas 8 does not need to be set to expand outward. By indenting the adhesive material layer 3 between the adjacent curved areas 8 on the inner side of the edge of the display panel 1, the risk of the adhesive material layer 3 overflowing relative to the display panel 1 after being squeezed can be reduced.

[0069] In this embodiment, the adhesive material layer 3 where no open bubbles are generated between adjacent curved areas 8 is retracted relative to the display panel 1 , thereby reducing the risk of adhesive overflow from the adhesive material layer 3 .

[0070] In one embodiment, in the curved area 8 , the edge of the first adhesive layer 31 is flush with the edge of the display panel 1 .

[0071] In one embodiment, the adhesive material layer 3 further includes a third adhesive layer, which is disposed between the first adhesive layer 31 and the second adhesive layer 32 . The cohesive force of the third adhesive layer is greater than that of the second adhesive layer 32 .

[0072] In one embodiment, the bonding strength between the second adhesive layer 32 and the cover plate 4 is greater than the bonding strength between the first adhesive layer 31 and the polarizer 2 , and the bonding strength between the second adhesive layer 32 and the cover plate 4 is greater than the bonding strength between the third adhesive layer and the first adhesive layer 31 .

[0073] In one embodiment, the first adhesive layer 31 is made of any one of hot melt adhesive and UV curing adhesive, and the second adhesive layer 32 is made of any one of solvent adhesive and non-UV curing adhesive.

[0074] Wherein, the solvent-processed glue is synthesized by dissolving glue.

[0075] In one embodiment, referring to FIG. 3 , the curved screen display module 10 further includes a back plate 6 and a heat sink 7 located on a side of the display panel 1 away from the polarizer 2 .

[0076] The heat dissipation plate 7 is disposed on a side of the back plate 6 away from the display panel 1 .

[0077] In one embodiment, referring to FIG. 3 , the curved screen display module 10 further includes an ink layer 5 .

[0078] The ink layer 5 is disposed between the adhesive material layer 3 and the cover plate 4 .

[0079] The adhesive material layer 3 includes a first adhesive layer 31 and a second adhesive layer 32 .

[0080] In one embodiment, the adhesive material layer is made of optical adhesive.

[0081] By dividing the adhesive material layer 3 into at least two layers, namely, including at least a first adhesive layer 31 and a second adhesive layer 32, the present application achieves a greater 180-degree peeling force in the second adhesive layer 32 in surface contact with the cover plate 4, while the first adhesive layer 31, which is not in contact with the cover plate 4, has a greater cohesive force. On the one hand, the high bonding strength at the interface between the second adhesive layer 32 and the cover plate 4 can reduce the generation of open bubbles. On the other hand, because the cohesive force of the first adhesive layer 31 is greater than that of the second adhesive layer 32, the presence of the first adhesive layer 31 can enhance the overall cohesive strength of the adhesive material layer 3, thereby reducing the generation of closed bubbles within the adhesive material layer 3. By reducing bubbles, failure of the adhesive material layer 3 is avoided.

[0082] The present application also proposes a terminal device, which includes the above-mentioned curved screen display module, wherein the curved screen display module also includes at least one of a back panel, a cover panel, an optical film, and a polarizer. The terminal device includes but is not limited to a mobile phone, a laptop computer, and a tablet computer.

[0083] The curved screen display module provided by the embodiment of the present application includes a display panel, a polarizer, an adhesive material layer, and a cover plate, wherein the polarizer is arranged on one side surface of the display panel, the cover plate is arranged on the side surface of the polarizer away from the display panel, and the adhesive material layer is located between the polarizer and the cover plate; wherein the adhesive material layer includes at least a first adhesive layer and a second adhesive layer, the first adhesive layer is arranged in surface contact with the polarizer, and the second adhesive layer is arranged in surface contact with at least a portion of the cover plate, the 180-degree peel force of the second adhesive layer is greater than the 180-degree peel force of the first adhesive layer, and / or the cohesive force of the first adhesive layer is greater than the cohesive force of the second adhesive layer; by dividing the adhesive material layer into at least two layers, the 180-degree peel force of the second adhesive layer in contact with the cover plate is greater, thereby improving the bonding strength between the adhesive material layer and the cover plate and reducing the generation of open bubbles, or the cohesive force of the first adhesive layer arranged away from the cover plate is greater, reducing the generation of closed bubbles in the adhesive material layer, thereby reducing bubbles and avoiding failure of the adhesive material layer.

[0084] The above describes in detail the curved screen display module provided by the embodiments of the present application. Without departing from the spirit and essential points of the present application, those skilled in the art may make various corresponding changes and modifications based on the present application, and such corresponding changes and modifications shall fall within the scope of protection of the claims appended to this application.

Claims

1. A curved screen display module, comprising: Display panel; an adhesive material layer, the adhesive material layer being disposed on one side of the display panel; a cover plate, the cover plate being disposed on a surface of the adhesive material layer that is away from the display panel; The adhesive material layer includes a first adhesive layer and a second adhesive layer, the first adhesive layer is arranged in surface contact with the polarizer, and the second adhesive layer is arranged in surface contact with at least a portion of the cover plate; The 180-degree peeling force of the second adhesive layer is set to be greater than the 180-degree peeling force of the first adhesive layer, and / or the cohesive force of the first adhesive layer is set to be greater than the cohesive force of the second adhesive layer.

2. The curved screen display module according to claim 1, wherein: The thickness of the second adhesive layer is smaller than that of the first adhesive layer.

3. The curved screen display module according to claim 2, wherein: The thickness of the first adhesive layer is d1, and the thickness of the second adhesive layer is d2, wherein 15 micrometers ≤ d2 ≤ 75 micrometers, and d1 + d2 ≤ 200 micrometers.

4. The curved screen display module according to claim 1, wherein: The curved screen display module includes a straight edge area and a curved area located between adjacent straight edge areas. In the curved area, the edge of the second adhesive layer is set beyond the edge of the display panel, and the edge of the second adhesive layer is located on the inner side of the edge of the cover plate.

5. The curved screen display module according to claim 4, wherein: In the straight edge area, the edge of the display panel is arranged beyond the edge of the adhesive material layer.

6. The curved screen display module according to claim 4, wherein: In the curved area, an edge of the first adhesive layer is flush with an edge of the display panel.

7. The curved screen display module according to claim 1, wherein: The adhesive material layer further includes a third adhesive layer, which is disposed between the first adhesive layer and the second adhesive layer. The cohesive force of the third adhesive layer is greater than the cohesive force of the second adhesive layer.

8. The curved screen display module according to claim 7, wherein: The curved screen display module further includes a polarizer, which is arranged on one side of the display panel, and the adhesive material layer is located between the polarizer and the cover plate; The bonding strength between the second adhesive layer and the cover plate is greater than the bonding strength between the first adhesive layer and the polarizer, and the bonding strength between the second adhesive layer and the cover plate is greater than the bonding strength between the third adhesive layer and the first adhesive layer.

9. The curved screen display module according to claim 1, wherein: The first adhesive layer is made of any one of hot melt adhesive and UV curing adhesive, and the second adhesive layer is made of any one of solvent adhesive and non-UV curing adhesive.

10. The curved screen display module according to claim 7, wherein: The curved screen display module further includes a back plate and a heat sink located on a side of the display panel away from the polarizer. The heat sink is arranged on a side of the back plate away from the display panel.

11. The curved screen display module according to claim 1, wherein: The curved screen display module further includes an ink layer, which is arranged between the adhesive material layer and the cover plate.

12. A terminal device, comprising a curved screen display module, wherein the curved screen display module comprises: Display panel; an adhesive material layer, the adhesive material layer being disposed on one side of the display panel; a cover plate, the cover plate being disposed on a surface of the adhesive material layer that is away from the display panel; The adhesive material layer includes a first adhesive layer and a second adhesive layer, the first adhesive layer is arranged in surface contact with the polarizer, and the second adhesive layer is arranged in surface contact with at least a portion of the cover plate; The 180-degree peeling force of the second adhesive layer is set to be greater than the 180-degree peeling force of the first adhesive layer, and / or the cohesive force of the first adhesive layer is set to be greater than the cohesive force of the second adhesive layer.

13. The terminal device according to claim 12, wherein: The thickness of the second adhesive layer is smaller than that of the first adhesive layer.

14. The terminal device according to claim 13, wherein: The thickness of the first adhesive layer is d1, and the thickness of the second adhesive layer is d2, wherein 15 micrometers ≤ d2 ≤ 75 micrometers, and d1 + d2 ≤ 200 micrometers.

15. The terminal device according to claim 12, wherein: The curved screen display module includes a straight edge area and a curved area located between adjacent straight edge areas. In the curved area, the edge of the second adhesive layer is set beyond the edge of the display panel, and the edge of the second adhesive layer is located on the inner side of the edge of the cover plate.

16. The terminal device according to claim 15, wherein: In the straight edge area, the edge of the display panel is arranged beyond the edge of the adhesive material layer.

17. The terminal device according to claim 15, wherein: In the curved area, an edge of the first adhesive layer is flush with an edge of the display panel.

18. The terminal device according to claim 12, wherein: The adhesive material layer further includes a third adhesive layer, which is disposed between the first adhesive layer and the second adhesive layer. The cohesive force of the third adhesive layer is greater than the cohesive force of the second adhesive layer.

19. The terminal device according to claim 18, wherein: The curved screen display module further includes a polarizer, which is arranged on one side of the display panel, and the adhesive material layer is located between the polarizer and the cover plate; The bonding strength between the second adhesive layer and the cover plate is greater than the bonding strength between the first adhesive layer and the polarizer, and the bonding strength between the second adhesive layer and the cover plate is greater than the bonding strength between the third adhesive layer and the first adhesive layer.

20. The terminal device according to claim 12, wherein: The first adhesive layer is made of any one of hot melt adhesive and UV curing adhesive, and the second adhesive layer is made of any one of solvent adhesive and non-UV curing adhesive.

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