External hanging type touch screen and preparation method thereof

Abstract

The invention provides an external hanging type TP which comprises a touch control substrate, a touch control layer, an external hanging type TP, a touch control layer and an external hanging type TP substrate, wherein the touch control layer is arranged on the touch control substrate; the metal wiring layer is arranged on the touch substrate; the insulating layer covers the metal wiring layer; the insulating layer is in contact with the touch substrate; the insulating layer is covered with the transparent conductive coating, and the transparent conductive coating is not in electric contact with the touch substrate. The invention also provides a preparation method of the composition. The transparent conductive coating covers the insulating layer of the externally-hung TP, the transparent conductive coating does not make electric contact with the touch substrate, the transparent conductive coating can be subjected to an electrification performance test, if the transparent conductive coating is conductive, it is indicated that the insulating layer is damaged or missed in coating, and if the transparent conductive coating is not conductive, the transparent conductive coating does not make electric contact with the touch substrate. The transparent conductive coating is electrically connected with the metal wiring layer, and if the transparent conductive coating is not conductive, the insulating layer is not damaged or missed to be coated, so that the yield of the externally-hung touch screen can be improved, and the touch failure caused by naked and missed wiring is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic equipment, and in particular to an external touch screen and a preparation method thereof. Background Art

[0002] The touch screen is an input device that significantly improves the human-machine interface, and has the advantages of being intuitive, simple, and fast. The external touch screen (TP) is a touch detection device of the touch screen system that is directly installed in front of the display device. This type of touch screen is easy to install and is very suitable for temporary use.

[0003] Existing external TPs generally use an insulating layer to insulate the silver paste wiring around the touch screen. If the insulating layer is slightly damaged, the silver paste wiring will be exposed for a long time, which may cause circuit corrosion and circuit breakage due to water erosion, resulting in insensitive touch or even failure. Summary of the invention

[0004] In view of this, the technical problem to be solved by the present invention is to provide an external touch screen and a preparation method thereof. The external touch screen provided by the present application can detect whether the insulating layer is damaged during the preparation process, thereby improving the yield rate of the external touch screen and avoiding touch failure caused by wiring leakage.

[0005] The present application provides an external TP, including:

[0006] A touch control substrate, on which a touch control layer is disposed;

[0007] A metal wiring layer disposed on the touch control substrate;

[0008] An insulating layer covering the metal wiring layer, wherein the insulating layer is in contact with the touch control substrate;

[0009] A transparent conductive coating is covered on the insulating layer, and the transparent conductive coating is not in electrical contact with the touch layer.

[0010] In some specific implementations, the transparent conductive coating does not contact the touch layer.

[0011] In some specific implementations, the transparent conductive coating does not cover the touch layer.

[0012] In some specific implementations, the transparent conductive coating is a transparent conductive light-emitting layer.

[0013] In some specific implementations, the transparent conductive coating is a transparent conductive photoluminescent layer or a transparent conductive electroluminescent layer.

[0014] In some specific implementations, the external TP further includes:

[0015] A cover plate is arranged on the transparent conductive coating layer by optical adhesive.

[0016] The present application also provides a method for preparing an external TP, comprising the following steps:

[0017] Providing a touch substrate, on which a touch layer is disposed;

[0018] Disposing a metal wiring layer on the touch control substrate;

[0019] An insulating layer is covered on the metal wiring layer, wherein the insulating layer is in contact with the touch control substrate;

[0020] Covering the insulating layer with a transparent conductive coating, wherein the transparent conductive coating is not in electrical contact with the touch layer;

[0021] The patch electrode is placed on the surface of the transparent conductive coating for electrical testing to detect whether the insulating layer is damaged. If the test result shows no damage, the external TP is obtained.

[0022] In some specific implementations, the transparent conductive coating is a transparent conductive photoluminescent layer. Before the electrical test, the transparent conductive photoluminescent layer is excited by light to detect whether the transparent conductive photoluminescent layer is intact. If it is intact, the electrical test is performed.

[0023] In some specific implementations, the transparent conductive coating is a transparent conductive electroluminescent layer. Before the electrical test, the transparent conductive photoluminescent layer is excited by electricity to detect whether the transparent conductive electroluminescent layer is intact. If it is intact, the electrical test is performed.

[0024] In some specific implementations, the transparent conductive coating does not cover the electrodes of the touch layer.

[0025] The external TP provided by the present application includes: a touch substrate, on which a touch layer is arranged; a metal wiring layer arranged on the touch substrate; an insulating layer covering the metal wiring layer, the insulating layer being in contact with the touch substrate; and a transparent conductive coating covering the insulating layer, the transparent conductive coating not being in electrical contact with the touch substrate. The present application covers the insulating layer of the external TP with a transparent conductive coating, the transparent conductive coating not being in electrical contact with the touch substrate. When preparing the external TP, the transparent conductive coating can be tested for its electrical performance. If the transparent conductive coating is conductive, it means that the insulating layer is damaged or not coated, and the transparent conductive coating is electrically connected to the metal wiring layer. If the transparent conductive coating is not conductive, it means that the insulating layer is not damaged or not coated, thereby improving the yield rate of the external touch screen and avoiding touch failure caused by wiring leakage.

[0026] Furthermore, the transparent conductive coating is a transparent conductive photoluminescent layer or a transparent conductive electroluminescent layer. Under light excitation or electrical excitation, the transparent conductive coating can emit light, thereby detecting the integrity of the transparent conductive coating, which is beneficial to the detection of whether the insulating layer is damaged. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the longitudinal section structure of the external TP disclosed in the prior art;

[0028] Figure 2 A top view of the external TP disclosed in the prior art;

[0029] Figure 3 A schematic diagram of the longitudinal section structure of the external TP provided in an embodiment of the present application;

[0030] Figure 4 A schematic diagram of the insulation layer integrity test structure provided in an embodiment of the present application;

[0031] Wherein, the reference numerals represent:

[0032] 11 is a touch control substrate;

[0033] 110 is a touch layer;

[0034] 12 is a metal wiring layer;

[0035] 13 is an insulating layer;

[0036] 14 is a first optical adhesive;

[0037] 15 is a cover plate;

[0038] 16 is a second optical adhesive;

[0039] 17 is a screen module;

[0040] 21 is a touch control substrate;

[0041] 210 is a touch layer;

[0042] 22 is a metal wiring layer;

[0043] 23 is an insulating layer;

[0044] 24 is a transparent conductive layer;

[0045] 25 is an electrode patch. DETAILED DESCRIPTION

[0046] The present invention provides an external touch screen and a method for preparing the same. Those skilled in the art can refer to the contents of this article and appropriately improve the process parameters to achieve the same. It should be particularly noted that all similar replacements and modifications are obvious to those skilled in the art and are considered to be included in the present invention. The methods and applications of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the methods and applications of this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0047] Existing external TP generally uses an insulating layer to insulate the silver paste wiring around the touch screen, see Figure 1 and Figure 2 , Figure 1 It is a schematic diagram of the longitudinal section structure of the external TP disclosed in the prior art. Figure 2 It is a top view of the external TP disclosed in the prior art. Among them, 11 is a touch substrate, on which a touch layer 110 is arranged; 12 is a metal wiring layer arranged on the touch substrate 11; 13 is an insulating layer covering the metal wiring layer 12; 14 is a first optical adhesive; 15 is a cover plate, which is covered on the surface of the touch substrate 11 through the first optical adhesive 14; 16 is a second optical adhesive; 17 is a screen module, which is covered on the back of the touch substrate 11 through the second optical adhesive 16.

[0048] In the existing external TP structure, the insulating layer 13 covers the surface of the metal wiring layer 12 to prevent the metal wiring layer 12 from being exposed. However, when preparing the external TP, the existing technology cannot detect the slight damage of the insulating layer 13, and the silver paste wiring is exposed for a long time, which may cause circuit corrosion and circuit breakage due to water erosion, thereby causing insensitive touch or even failure.

[0049] Based on this, the present application provides an external TP, including:

[0050] A touch control substrate, on which a touch control layer is disposed;

[0051] A metal wiring layer disposed on the touch control substrate;

[0052] An insulating layer covering the metal wiring layer, wherein the insulating layer is in contact with the touch control substrate;

[0053] A transparent conductive coating layer covers the insulating layer, and the transparent conductive coating layer is not in electrical contact with the touch substrate.

[0054] See also Figure 3 , Figure 3This is a schematic diagram of the longitudinal cross-sectional structure of an external TP provided in an embodiment of the present application, wherein 21 is a touch substrate on which a touch layer 210 is arranged; 22 is a metal wiring layer arranged on the touch substrate 21; 23 is an insulating layer covering the metal wiring layer 22, and 24 is a transparent conductive layer covering the insulating layer 23, and the transparent conductive coating 24 is not in electrical contact with the touch layer 210.

[0055] The external TP provided in the present application includes a touch substrate 21, on which a touch layer 210 is disposed. Specifically, the touch substrate 21 is a functional substrate for realizing touch control, and the present application has no special restrictions thereon. The touch layer 210 can be a patterned electrode, such as an ITO sensor, and the present application has no special restrictions thereon.

[0056] The metal wiring layer 22 is disposed on the touch substrate 21 to realize the touch screen circuit conduction. The present application has no special restrictions on the structure of the metal wiring layer 22. GND circuits, GND / Guard circuits, Tx circuits, etc. can be selected according to needs, and metals such as silver, silver paste, copper, nickel, etc. are used as conductors.

[0057] The insulating layer 23 covers the metal wiring layer 22 to protect the metal wiring layer 22. One side of the insulating layer 22 contacts the touch substrate 21, and the other side contacts the touch layer 210, so as to completely cover and isolate the metal wiring layer 22.

[0058] In order to detect whether the insulating layer 23 is damaged or not coated, a transparent conductive coating 24 is covered on the insulating layer 23 in the present application, and the transparent conductive coating 24 is not electrically connected to the touch substrate 21. The transparent conductive coating 24 is used to detect whether the insulating layer 23 is damaged or not coated during the preparation of the external TP. The principle is as follows: the transparent conductive coating 24 is electrically detected. Since it is not electrically connected to the touch substrate, especially the touch layer, when the insulating layer is not damaged or not coated, the transparent conductive coating 24 does not conduct the circuit; when the insulating layer 23 is damaged or not coated, the transparent conductive coating 24 is connected to the metal wiring layer 22, causing the transparent conductive coating 24 to be charged, thereby realizing the detection of the integrity of the insulating layer 23. In some specific implementations, the transparent conductive coating 24 is not electrically connected to the touch substrate 21, nor is it in contact with the touch layer 210. At the same time, the transparent conductive layer can also enhance the antistatic ability of the external TP. In order to further ensure the accuracy of the detection, the transparent conductive coating 24 also does not cover the touch layer 210 , that is, the transparent conductive coating does not cover the insulating layer covering the touch layer 210 .

[0059] In some specific implementations, the transparent conductive coating is a transparent conductive luminescent layer, that is, the transparent conductive coating can emit light. In some specific implementations, the transparent conductive coating is a transparent conductive photoluminescent layer, that is, the transparent conductive coating can be excited by light, such as ultraviolet light, visible light, etc., to emit fluorescence or other detectable light, so as to detect the integrity of the transparent conductive coating. The present application has no special restrictions on the material of the transparent conductive photoluminescent layer, and the photoluminescent material can be added to the transparent conductive material.

[0060] In some specific implementations, the transparent conductive coating is a transparent conductive electroluminescent layer, that is, the transparent conductive coating can be excited under the action of electric current to emit fluorescence or other detectable light, thereby being used to detect the integrity of the transparent conductive coating. The present application has no special restrictions on the material of the transparent conductive electroluminescent layer, and the electroluminescent material can be added to the transparent conductive material.

[0061] The present application has no special restrictions on the thickness of the transparent conductive layer 24, as long as it can completely cover the insulating layer 23. In some specific implementations, the thickness of the transparent conductive layer 24 is preferably 15 to 20 μm, more preferably 17 μm, which can be kept consistent with the thickness of the insulating layer to ensure that after the insulating layer is damaged, the conductive layer can completely fill and cover the defective position.

[0062] In some specific implementations, the external TP provided by the present application further includes a first optical adhesive and a cover plate, and the cover plate is covered on the surface of the touch substrate by the first optical adhesive. In some specific implementations, the external TP further includes a second optical adhesive and a screen module, and the screen module is covered on the back of the touch substrate by the second optical adhesive.

[0063] The present application also provides a method for preparing an external TP, comprising the following steps:

[0064] Providing a touch substrate, on which a touch layer is disposed;

[0065] Disposing a metal wiring layer on the touch control substrate;

[0066] An insulating layer is covered on the metal wiring layer, wherein the insulating layer is in contact with the touch control substrate;

[0067] Covering the insulating layer with a transparent conductive coating, wherein the transparent conductive coating is not in electrical contact with the touch layer;

[0068] The patch electrode is placed on the surface of the transparent conductive coating for electrical testing to detect whether the insulating layer is damaged. If the test result shows no damage, the external TP is obtained.

[0069] The present application first provides a touch substrate, on which a touch layer is disposed. The present application has no special restrictions on the method for disposing the touch layer, and the touch layer can be formed by etching technology. In some specific implementations, the touch layer is an ITO sensor.

[0070] The present application sets a metal wiring layer on the touch substrate. The present application has no special restrictions on the method of setting the metal wiring layer, which can be selected according to the touch layer. The present application has no special restrictions on the metal used for the metal wiring layer, which can be silver paste, silver, copper, gold, etc., preferably silver paste.

[0071] After the metal routing layer is set, an insulating layer is covered on the metal routing layer, and the insulating layer is in contact with the touch substrate. The present application can cover the insulating layer on the metal routing layer by screen printing, and one side of the insulating layer is in contact with the touch substrate, and the other side is in contact with the touch layer, so as to form a complete coverage and isolation of the metal routing layer. It can be understood by those skilled in the art that the present application can also form an insulating layer on the metal routing layer by other methods, such as coating, spraying, etc.

[0072] After forming the insulating layer, the present application forms a transparent conductive coating on the insulating layer. The transparent conductive coating covers the insulating layer and is not electrically connected to the touch substrate, especially not in contact with the touch layer. In order to further ensure the accuracy of the detection, the transparent conductive coating does not cover the touch layer, that is, the transparent conductive coating does not cover the insulating layer covering the touch layer. The present application has no special restrictions on the formation method of the transparent conductive coating, and screen printing or covering spraying can be used. The specific process parameters can be selected according to the formula of Ge Jun's transparent conductive coating. The formula of the transparent conductive coating described in the present application is also not particularly limited, and it can be configured by yourself or purchased on the market.

[0073] In some specific implementations, the transparent conductive coating is a transparent conductive photoluminescent layer, that is, a photoluminescent material is added to the transparent conductive coating so that the coating can emit visible light such as fluorescence under the excitation of light of a specific wavelength, such as infrared light, ultraviolet light or visible light. Before the electrical test, the transparent conductive photoluminescent layer is excited by light to detect whether the transparent conductive photoluminescent layer is intact. If it is intact, the electrical test is performed.

[0074] In some specific implementations, the transparent conductive coating is a transparent conductive electroluminescent layer, that is, an electroluminescent material is added to the transparent conductive coating so that the coating can emit visible light such as fluorescence under the excitation of electric current. Before the electrical test, the transparent conductive electroluminescent layer is excited by electric current to detect whether the transparent conductive electroluminescent layer is intact. If it is intact, the electrical test is performed.

[0075] In the present application, when the transparent conductive coating is a transparent conductive photoluminescent layer or a transparent conductive electroluminescent layer, the integrity of the transparent conductive coating can be ensured, and the accuracy of the insulating layer detection result can be ensured.

[0076] After forming the transparent conductive coating, the insulation layer is tested for integrity as follows:

[0077] The patch electrode is placed on the surface of the transparent conductive coating for electrical testing to detect whether the insulating layer is damaged. If the test result shows no damage, the external TP is obtained.

[0078] See also Figure 4 , Figure 4 The schematic diagram of the insulation layer integrity test structure provided in the embodiment of the present application, wherein 25 is a patch electrode, and the patch electrode 25 is connected to an external circuit / fixture. The external circuit / fixture is turned on to perform electrical detection on the transparent conductive coating 24. Since it is not electrically connected to the touch substrate, especially the touch layer, when the insulating layer is not damaged or not coated, the transparent conductive coating 24 does not conduct the circuit; when the insulating layer 23 is damaged or not coated, the transparent conductive coating 24 is connected to the metal wiring layer 22, causing the transparent conductive coating 24 to be charged, thereby realizing the detection of the integrity of the insulating layer 23.

[0079] If the test results show no damage or missing coating, a good quality external TP can be obtained; if the test results indicate damage or missing coating, the damage or missing coating of the insulating layer is repaired and a good quality external TP can be obtained after retesting, thereby improving the product yield.

[0080] The present application covers the insulating layer of the external TP with a transparent conductive coating, and the transparent conductive coating is not in electrical contact with the touch substrate. When preparing the external TP, the transparent conductive coating can be tested for its electrical performance. If the transparent conductive coating is conductive, it means that the insulating layer is damaged or not coated, and the transparent conductive coating is electrically connected to the metal wiring layer. If the transparent conductive coating is not conductive, it means that the insulating layer is not damaged or not coated, thereby improving the yield rate of the external touch screen and avoiding touch failure caused by wiring leakage. Furthermore, the transparent conductive coating is a transparent conductive photoluminescent layer or a transparent conductive electroluminescent layer. Under light excitation or electrical excitation, the transparent conductive coating can emit light, thereby detecting the integrity of the transparent conductive coating, which is conducive to detecting whether the insulating layer is damaged.

[0081] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An external TP, characterized in that: include: A touch control substrate, on which a touch control layer is disposed; A metal wiring layer disposed on the touch control substrate; An insulating layer covering the metal wiring layer, wherein the insulating layer is in contact with the touch control substrate; A transparent conductive coating is covered on the insulating layer, and the transparent conductive coating is not in electrical contact with the touch layer.

2. The external TP according to claim 1, characterized in that: The transparent conductive coating layer does not contact the touch control layer.

3. The external TP according to claim 2, characterized in that: The transparent conductive coating does not cover the touch control layer.

4. The external TP according to claim 1, characterized in that: The transparent conductive coating is a transparent conductive light-emitting layer.

5. The external TP according to claim 4, characterized in that: The transparent conductive coating is a transparent conductive photoluminescent layer or a transparent conductive electroluminescent layer.

6. The external TP according to any one of claims 1 to 5, characterized in that: Also includes: A cover plate is arranged on the transparent conductive coating layer by optical adhesive.

7. A method for preparing an external TP, characterized in that: The following steps are involved: Providing a touch substrate, on which a touch layer is disposed; Disposing a metal wiring layer on the touch control substrate; An insulating layer is covered on the metal wiring layer, wherein the insulating layer is in contact with the touch control substrate; Covering the insulating layer with a transparent conductive coating, wherein the transparent conductive coating is not in electrical contact with the touch layer; The patch electrode is placed on the surface of the transparent conductive coating for electrical testing to detect whether the insulating layer is damaged. If the test result shows no damage, the external TP is obtained.

8. The preparation method according to claim 7, characterized in that: The transparent conductive coating is a transparent conductive photoluminescent layer. Before the electrical test, the transparent conductive photoluminescent layer is excited by light to detect whether the transparent conductive photoluminescent layer is intact. If it is intact, the electrical test is performed.

9. The preparation method according to claim 7, characterized in that: The transparent conductive coating is a transparent conductive electroluminescent layer. Before the electrical test, the transparent conductive photoluminescent layer is excited by electricity to detect whether the transparent conductive electroluminescent layer is complete. If it is complete, the electrical test is performed.

10. The preparation method according to any one of claims 7 to 9, characterized in that: The transparent conductive coating does not cover the electrodes of the touch layer.

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