Sandwich touch structure and touch screen
By employing a sandwich-type touch structure and a wavy or serrated optical adhesive edge design in automotive touchscreens, the problem of interface stress caused by the difference in thermal expansion coefficients between the glass substrate and the optical adhesive layer is solved, edge delamination and bubble problems are improved, and the reliability and durability of the touchscreen are enhanced.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- TRULY OPTO ELECTRONICS
- Filing Date
- 2025-06-24
- Publication Date
- 2026-07-14
AI Technical Summary
The large difference in thermal expansion coefficients between the glass substrate and the optical adhesive layer of existing automotive touch screens makes it easy for the interface stress to cause edge delamination or bubble problems during temperature cycling tests.
The sandwich touch structure is adopted, with the upper ITO circuit layer and the lower ITO circuit layer placed between the upper glass substrate and the lower glass substrate. The edge of the optical adhesive layer adopts a wavy or sawtooth structure to increase the effective interface length and eliminate stress singularities. The gap is filled and sealed with edge sealing silicone to prevent moisture intrusion.
It effectively disperses interface stress, prevents edge delamination and bubble problems, and improves the reliability and durability of the touch screen.
Smart Images
Figure CN224501256U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to touch technology, and more particularly to a sandwich-type touch structure and a touch screen. Background Technology
[0002] To improve the reliability of automotive touchscreens, Chinese Patent Application No. CN202122226181.8 discloses a touch structure. The touch structure includes an upper ITO glass, a lower ITO glass, and an optical adhesive layer bonding the upper and lower ITO glass. The upper ITO glass consists of an upper glass substrate and an upper ITO functional layer located on the surface of the upper glass substrate. The lower ITO glass consists of a lower glass substrate and a lower ITO functional layer located on the surface of the lower glass substrate. Its layered stacked structure, from top to bottom, consists of an upper glass substrate, an upper ITO functional layer, an optical adhesive layer, a lower ITO functional layer, and a lower glass substrate. The upper and lower ITO functional layers are sensor ITO pattern layers, and the upper glass substrate is a protective glass cover. This patent places the touch function layer of the touch screen between two pieces of glass and isolates it with an optical adhesive layer. The optical adhesive layer not only serves as insulation but also as protection, saving an insulation process and improving product reliability. The upper ITO function layer is electrically connected to the bonding pins through conductive epoxy resin, which achieves both conductivity and protection of the touch function layer.
[0003] However, the large difference in the coefficient of thermal expansion between the glass substrate and the optical adhesive layer can easily lead to interfacial stress during temperature cycling tests (such as automotive-grade -40℃ to 85℃), resulting in edge delamination or bubbles. Utility Model Content
[0004] To address the shortcomings of the existing technology, this invention provides a sandwich-type touch structure that can disperse the stress distribution at the interface, thereby effectively improving edge delamination or bubble problems.
[0005] This utility model also provides a touch screen, including the above-mentioned sandwich-type touch structure.
[0006] The technical problem to be solved by this utility model is achieved through the following technical solution:
[0007] A sandwich-type touch structure includes an upper ITO glass, an optical adhesive layer, and a lower ITO glass, wherein the upper ITO glass and the lower ITO glass are bonded and fixed to each other by the optical adhesive layer; the upper ITO glass includes an upper glass substrate and an upper ITO circuit layer, the upper ITO circuit layer being disposed on the surface of the upper glass substrate facing the lower ITO glass; the lower ITO glass includes a lower glass substrate and a lower ITO circuit layer, the lower ITO circuit layer being disposed on the surface of the lower glass substrate facing the upper ITO glass; at least one edge of the optical adhesive layer has a wavy structure or a serrated structure.
[0008] Furthermore, the sandwich-type touch structure includes a visible area and a peripheral area, the peripheral area surrounding the visible area; at least one edge of the optical adhesive layer, which employs the wavy or serrated structure, is located within the peripheral area.
[0009] Furthermore, the length of the wavy or sawtooth structure is between 1.0 and 1.5 mm, and the maximum width is between 0.4 and 0.8 mm.
[0010] Furthermore, the sandwich-type touch structure also includes edge-sealing silicone, which is located between the upper ITO glass and the lower ITO glass, and is disposed outside at least one edge of the optical adhesive layer that adopts the wavy structure or the sawtooth structure.
[0011] Furthermore, the upper ITO glass also includes a photoresist ink layer, which is disposed between the upper glass substrate and the upper ITO circuit layer, and covers the visible area of the sandwich touch structure while avoiding the peripheral area of the sandwich touch structure.
[0012] Furthermore, the upper ITO circuit layer includes an upper sensor circuit and an upper peripheral trace, the upper peripheral circuit being connected to the upper sensor circuit; the upper sensor circuit is disposed on the upper glass substrate of the visible area, and the upper peripheral trace is disposed on the photoresist ink layer of the peripheral area.
[0013] Furthermore, the upper ITO glass also includes a reverse cover ink layer, which is disposed on the surface of the upper ITO circuit layer facing the lower ITO glass and covers the visible area of the sandwich touch structure, so as to completely cover the photoresist ink layer and the upper peripheral traces, while avoiding the peripheral area of the sandwich touch structure.
[0014] Furthermore, the lower ITO circuit layer includes a lower sensor circuit and a lower peripheral trace, the lower peripheral circuit being connected to the lower sensor circuit; the lower sensor circuit is disposed on the lower glass substrate of the visible area, and the lower peripheral trace is disposed on the lower glass substrate of the peripheral area.
[0015] Furthermore, the sandwich-type touch structure also includes an upper FPC and a lower FPC, wherein the upper FPC is bonded to one side edge of the upper ITO glass, and the lower FPC is bonded to one side edge of the lower ITO glass.
[0016] A touchscreen comprising the aforementioned sandwich-type touch structure.
[0017] The present invention has the following beneficial effects: The sandwich-type touch structure of the present invention sets the upper ITO circuit layer and the lower ITO circuit layer between the upper glass substrate and the lower glass substrate to form a sandwich structure. At the same time, the wavy structure or sawtooth structure is adopted on the edge of the optical adhesive layer, thereby increasing the effective interface length between the optical adhesive layer and the upper ITO glass and the lower ITO glass, so as to disperse the interface stress caused by the difference in thermal expansion coefficient between the optical adhesive layer and the upper ITO glass and the lower ITO glass. At the same time, the continuously changing wavy structure or sawtooth structure eliminates stress singularities, so as to prevent the interface stress from being excessively concentrated at the four corners, thereby effectively improving the edge delamination or bubble problem. Attached Figure Description
[0018] Fig. 1 A schematic diagram of the stacked structure of the sandwich-type touch structure provided by this utility model.
[0019] Fig. 2 This is a schematic diagram of the edge structure of the optical adhesive layer in the sandwich-type touch structure provided by this utility model.
[0020] Fig. 3 A schematic diagram of the edge structure of the optical adhesive layer in another sandwich-type touch structure provided by this utility model. Detailed Implementation
[0021] The present invention will now be described in detail with reference to the accompanying drawings and embodiments, examples of which are shown in the drawings. Throughout the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.
[0022] In the description of this utility model, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0023] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "multiple" means two or more, unless otherwise explicitly specified.
[0024] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," "fixing," and "setting," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0025] Example 1
[0026] like Figs. 1-3 As shown, a sandwich-type touch structure includes an upper ITO glass 1, an optical adhesive layer 2, and a lower ITO glass 3. The upper ITO glass 1 and the lower ITO glass 3 are bonded and fixed to each other by the optical adhesive layer 2. The upper ITO glass 1 includes an upper glass substrate 11 and an upper ITO circuit layer 12, with the upper ITO circuit layer 12 disposed on the surface of the upper glass substrate 11 facing the lower ITO glass 3. The lower ITO glass 3 includes a lower glass substrate 31 and a lower ITO circuit layer 32, with the lower ITO circuit layer 32 disposed on the surface of the lower glass substrate 31 facing the upper ITO glass 1. At least one edge of the optical adhesive layer 2 adopts a wavy structure 31 or a sawtooth structure 32.
[0027] The sandwich-type touch structure of this invention forms a sandwich structure by placing the upper ITO circuit layer 12 and the lower ITO circuit layer 32 between the upper glass substrate 11 and the lower glass substrate 31. At the same time, the wavy structure 31 or sawtooth structure 32 is used on the edge of the optical adhesive layer 2, thereby increasing the effective interface length between the optical adhesive layer 2 and the upper ITO glass 1 and the lower ITO glass 3. This disperses the interface stress caused by the difference in thermal expansion coefficients between the optical adhesive layer 2 and the upper ITO glass 1 and the lower ITO glass 3. At the same time, the continuously changing wavy structure 31 or sawtooth structure 32 is used to eliminate stress singularities, so as to prevent the interface stress from being excessively concentrated at the four corners, thereby effectively improving edge delamination or bubble problems.
[0028] In this embodiment, the optical adhesive layer 3 is an OCA optical adhesive with a thickness between 100-300 μm.
[0029] Preferably, the length of the wavy structure 31 or the sawtooth structure 32 is between 1.0 and 1.5 mm, and the maximum width is between 0.4 and 0.8 mm.
[0030] The sandwich-type touch structure includes a visible area 100 and a peripheral area 200, with the peripheral area 200 surrounding the visible area 100; the optical adhesive layer 2 has at least one edge located within the peripheral area 200, which adopts the wavy structure 31 or the sawtooth structure 32.
[0031] The sandwich-type touch structure also includes edge sealing silicone 5, which is located between the upper ITO glass 1 and the lower ITO glass 3, and is disposed outside at least one edge of the optical adhesive layer 2 which adopts the wavy structure 31 or the sawtooth structure 32.
[0032] The edge-sealing silicone 5 has two main functions: one is to fill the edges of the optical adhesive layer 2 with a wavy structure 31 or a sawtooth structure 32 to eliminate the gap between the upper ITO glass 1 and the lower ITO glass 3, and the outer edge of the edge-sealing silicone 5 is flush with the edges of the upper ITO glass 1 and the lower ITO glass 3; the other is to seal the edges between the upper ITO glass 1 and the lower ITO glass 3 to prevent external moisture from entering.
[0033] The upper ITO glass 1 also includes a photoresist ink layer 13, which is disposed between the upper glass substrate 11 and the upper ITO circuit layer 12, and covers the visible area 100 of the sandwich touch structure, while avoiding the peripheral area 200 of the sandwich touch structure.
[0034] The ink color and ink pattern of the photoresist ink layer 13 can be determined according to the appearance requirements of the sandwich touch structure, and its thickness is between 4-8μm.
[0035] The upper ITO circuit layer 12 includes an upper sensor circuit and an upper peripheral trace, and the upper peripheral circuit is connected to the upper sensor circuit. The upper sensor circuit is disposed on the upper glass substrate 11 of the visible area 100, and the upper peripheral trace is disposed on the photoresist ink layer 13 of the peripheral area 200.
[0036] The upper ITO glass 1 also includes a reverse ink layer 14, which is disposed on the surface of the upper ITO circuit 12 layer facing the lower ITO glass 3 and covers the visible area 100 of the sandwich touch structure, so as to completely cover the photoresist ink layer 13 and the upper peripheral wiring, while avoiding the peripheral area 200 of the sandwich touch structure.
[0037] The reverse ink layer 14 is preferably black ink or gray semi-transparent ink, and its thickness is between 10-15 μm.
[0038] The lower ITO circuit layer 32 includes a lower sensor circuit and a lower peripheral trace. The lower peripheral circuit is connected to the lower sensor circuit. The lower sensor circuit is disposed on the lower glass substrate 31 of the visible area 100, and the lower peripheral trace is disposed on the lower glass substrate 31 of the peripheral area 200.
[0039] The sandwich-type touch structure also includes an upper FPC 6 and a lower FPC 7. The upper FPC 6 is bonded to one side edge of the upper ITO glass 1 and electrically connected to the upper peripheral wiring. The lower FPC 7 is bonded to one side edge of the lower ITO glass 3 and electrically connected to the lower peripheral wiring.
[0040] In this embodiment, both the upper and lower outer perimeter traces are traced using silver paste.
[0041] Example 2
[0042] A touch screen includes the sandwich-type touch structure described in Embodiment 1.
[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model and not to limit them. Although the present utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present utility model, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the scope of the technical solutions of the present utility model.
Claims
1. A sandwich-type touch structure, comprising an upper ITO glass, an optical adhesive layer, and a lower ITO glass, wherein the upper ITO glass and the lower ITO glass are bonded and fixed to each other by the optical adhesive layer; the upper ITO glass comprises an upper glass substrate and an upper ITO circuit layer, the upper ITO circuit layer being disposed on the surface of the upper glass substrate facing the lower ITO glass; the lower ITO glass comprises a lower glass substrate and a lower ITO circuit layer, the lower ITO circuit layer being disposed on the surface of the lower glass substrate facing the upper ITO glass; characterized in that, At least one edge of the optical adhesive layer has a wavy or serrated structure.
2. The sandwich-type touch structure according to claim 1, characterized in that, The sandwich-type touch structure includes a visible area and a peripheral area, with the peripheral area surrounding the visible area; at least one edge of the optical adhesive layer, which employs the wavy or serrated structure, is located within the peripheral area.
3. The sandwich-type touch structure according to claim 1 or 2, characterized in that, The length of the wavy or sawtooth structure is between 1.0 and 1.5 mm, and the maximum width is between 0.4 and 0.8 mm.
4. The sandwich-type touch structure according to claim 1 or 2, characterized in that, The sandwich-type touch structure also includes edge sealing silicone, which is located between the upper ITO glass and the lower ITO glass, and is disposed outside at least one edge of the optical adhesive layer that adopts the wavy structure or the sawtooth structure.
5. The sandwich-type touch structure according to claim 2, characterized in that, The upper ITO glass also includes a photoresist ink layer, which is disposed between the upper glass substrate and the upper ITO circuit layer, and covers the visible area of the sandwich touch structure while avoiding the peripheral area of the sandwich touch structure.
6. The sandwich-type touch structure according to claim 5, characterized in that, The upper ITO circuit layer includes an upper sensor circuit and an upper peripheral trace, the upper peripheral trace being connected to the upper sensor circuit; the upper sensor circuit is disposed on the upper glass substrate of the visible area, and the upper peripheral trace is disposed on the photoresist ink layer of the peripheral area.
7. The sandwich-type touch structure according to claim 6, characterized in that, The upper ITO glass also includes a reverse cover ink layer, which is disposed on the surface of the upper ITO circuit layer facing the lower ITO glass and covers the visible area of the sandwich touch structure, so as to completely cover the photoresist ink layer and the upper peripheral traces, while avoiding the peripheral area of the sandwich touch structure.
8. The sandwich-type touch structure according to claim 2, characterized in that, The lower ITO circuit layer includes a lower sensor circuit and a lower peripheral trace, the lower peripheral trace being connected to the lower sensor circuit; the lower sensor circuit is disposed on the lower glass substrate of the visible area, and the lower peripheral trace is disposed on the lower glass substrate of the peripheral area.
9. The sandwich-type touch structure according to claim 1, characterized in that, The sandwich-type touch structure also includes an upper FPC and a lower FPC. The upper FPC is bonded to one side edge of the upper ITO glass, and the lower FPC is bonded to one side edge of the lower ITO glass.
10. A touchscreen, characterized in that, Includes the sandwich-type touch structure as described in claim 1.