Cover plate with capacitive touch function

Abstract

The utility model provides a cover plate with a capacitive touch function, and relates to the technical field of touch screens. The cover plate with the capacitive touch function comprises a glass substrate, a transparent conducting layer arranged on the glass substrate, a nano composite material coating covering the transparent conducting layer, a black frame layer arranged on the edge of the glass substrate and a silver paste lead electrically connected with the transparent conducting layer. The transparent conductive layer comprises a plurality of metal wires, the plurality of metal wires are mutually connected to form a grid structure, the line width of the grid structure is 1-5 microns, and the line spacing is 50-200 microns; the nano composite material coating is formed by compounding nano particles and organic resin, and the thickness of the nano composite material coating is 100 nm to 1 [mu] m; the black frame layer is formed by printing mixed black ink, and the mixed black ink comprises black pigment and resin. By adopting the metal grid transparent conductive layer, the nano composite material coating and the mixed black ink, the problems caused by the use of the ITO film are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of touch screens, and in particular to a cover plate with a capacitive touch function. Background Art

[0002] Capacitive touch screen cover plates are key components of modern electronic devices, and their performance directly impacts user experience and product quality. Traditional capacitive touch screen cover plate technology primarily uses indium tin oxide (ITO) thin film as the transparent conductive layer.

[0003] However, the preparation process for ITO film is complex and costly, and its brittleness makes it susceptible to damage, reducing product reliability and yield. There is a certain contradiction between the conductivity and transmittance of ITO film, making it difficult to simultaneously meet the requirements of high transmittance and high sensitivity. To achieve high transmittance, the ITO film needs to be very thin, which reduces its conductivity and thus affects touch sensitivity.

[0004] Therefore, it is necessary to improve the existing capacitive touch screen cover technology to overcome the defects of the existing technology. Utility Model Content

[0005] In order to overcome the problems existing in the related art, the purpose of the present invention is to provide a cover plate with a capacitive touch function. The cover plate with a capacitive touch function adopts a metal grid transparent conductive layer, a nano-composite coating and a mixed black ink to overcome the problems caused by the use of ITO film in the prior art.

[0006] A capacitive touch cover comprises a glass substrate, a transparent conductive layer disposed on the glass substrate, a nanocomposite coating covering the transparent conductive layer, a black frame layer disposed at the edge of the glass substrate, and silver paste leads electrically connected to the transparent conductive layer.

[0007] The transparent conductive layer includes a plurality of metal lines, which are interconnected to form a grid structure. The grid structure has a line width of 1 μm to 5 μm and a line spacing of 50 μm to 200 μm.

[0008] The nanocomposite coating is composed of nanoparticles and organic resin, and the thickness of the nanocomposite coating is 100nm-1μm;

[0009] The black frame layer is printed by mixed black ink, and the mixed black ink contains black pigment and resin.

[0010] Compared to traditional ITO films, transparent conductive layers with metal grid structures achieve both high light transmittance and low resistance. This is due to the excellent conductivity of the metal material itself, and the grid structure reduces the area blocked by the metal wires, thereby increasing light transmittance. Nanocomposite coatings, reinforced by nanoparticles, significantly improve the hardness and wear resistance of the cover, effectively preventing scratches and extending its service life. Mixed black inks can be customized to achieve optimal light-blocking performance and adhesion to the glass substrate, improving the quality and reliability of the black frame layer.

[0011] In some embodiments, the metal material is selected from the group consisting of silver, copper, nickel, silver alloys, copper alloys, and nickel alloys.

[0012] These metals all have good electrical conductivity, ensuring low resistance in the transparent conductive layer, thereby improving touch sensitivity. The choice of different metals can be adjusted based on cost, performance, and process requirements. For example, silver has the best conductivity but is more expensive; copper has good conductivity and is relatively low in cost, but is easily oxidized; and nickel has moderate conductivity and is also moderate in cost.

[0013] In some embodiments, the shape of the grid structure is square, diamond or hexagonal;

[0014] Meshes of different shapes can have varying light transmittance and conductivity at the same line width and spacing. For example, a hexagonal mesh can provide higher light transmittance at the same line width and spacing. Light transmittance and conductivity can be optimized based on actual needs.

[0015] In some embodiments, the nanoparticles are SiO2, Al2O3, TiO2, or ZrO2;

[0016] The organic resin is acrylic resin, epoxy resin or polyurethane.

[0017] SiO2, Al2O3, TiO2, and ZrO2 are all common nanoparticle materials with varying degrees of hardness, wear resistance, and optical properties. Acrylic resins, epoxy resins, and polyurethanes are all commonly used organic resins with varying degrees of flexibility, adhesion, and weather resistance. By selecting the appropriate nanoparticles and organic resins, the properties of nanocomposite coatings, such as hardness, wear resistance, and light transmittance, can be tailored to meet specific needs.

[0018] In some embodiments, the black pigment is carbon black, graphite, black iron oxide, or black cobalt oxide;

[0019] The resin is acrylic resin, epoxy resin, polyurethane or silicone resin.

[0020] Carbon black, graphite, black iron oxide, and black cobalt oxide are all common black pigments, each with varying light-blocking properties and costs. Acrylic, epoxy, polyurethane, and silicone resins are all commonly used resins, each with varying adhesion, weatherability, and chemical resistance. By selecting the appropriate black pigment and resin, the light-blocking properties, adhesion, and durability of the black frame layer can be optimized.

[0021] In some embodiments, the transparent conductive layer is prepared by inkjet printing, screen printing, photolithography, or nanoimprinting.

[0022] Inkjet printing, screen printing, photolithography, and nanoimprinting are all common micro-nano manufacturing technologies, with varying degrees of precision, cost, and applicability. Using the right manufacturing method can improve manufacturing precision or reduce manufacturing costs.

[0023] In some embodiments, the nanocomposite coating is prepared by spray coating, spin coating, dip coating, or blade coating.

[0024] Spray coating, spin coating, dip coating, and blade coating are all common coating methods with different thickness uniformity, cost, and application range. Choosing the right coating method can control the coating thickness and improve the coating quality.

[0025] In some embodiments, the silver paste lead is prepared by screen printing, inkjet printing or dispensing, and is connected to the transparent conductive layer.

[0026] Screen printing, inkjet printing, and dispensing are all common printing or coating methods with different precision, cost, and application ranges. Choosing the right preparation method can improve the accuracy and reliability of silver paste leads.

[0027] In some embodiments, the metal material is silver nanowires, the grid structure is hexagonal, the line width is 2 μm, and the line spacing is 100 μm.

[0028] Silver nanowires have excellent conductivity, the hexagonal grid structure can improve transmittance, and the limitation of line width and line spacing can balance transmittance and conductivity.

[0029] In some embodiments, the metal material is silver;

[0030] The grid structure is hexagonal, with a line width of 2 μm and a line spacing of 100 μm;

[0031] The nanoparticles are SiO2, the organic resin is acrylic resin, and the thickness of the nanocomposite coating is 200nm;

[0032] The black pigment is carbon black, and the resin is silicone resin.

[0033] The beneficial effects of the utility model are:

[0034] The utility model provides a cover plate with a capacitive touch function, which includes a glass substrate, a transparent conductive layer arranged on the glass substrate, a nano-composite coating covering the transparent conductive layer, a black frame layer arranged at the edge of the glass substrate, and a silver paste lead electrically connected to the transparent conductive layer. Compared with the traditional ITO film, the transparent conductive layer with a metal grid structure can take into account both high light transmittance and low resistance, because the metal material itself has excellent conductivity, and the grid structure can reduce the blocking area of ​​the metal wire, thereby improving the light transmittance. Due to the reinforcing effect of the nanoparticles, the nano-composite coating can significantly improve the hardness and wear resistance of the cover plate, effectively prevent scratches, and extend the service life. The mixed black ink can be formulated according to the needs of the ratio of pigment and resin to obtain the best light-shielding performance and adhesion to the glass substrate, thereby improving the quality and reliability of the black frame layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Schematic diagram of a capacitive touch screen cover provided in this application.

[0036] Reference numerals:

[0037] 100, glass substrate; 200, transparent conductive layer; 300, nanocomposite coating; 400, black frame layer; 500, silver paste lead; 600, insulation layer. DETAILED DESCRIPTION

[0038] The following describes preferred embodiments of the present invention in more detail with reference to the accompanying drawings. Although preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. Rather, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0039] Example 1

[0040] like Figure 1 As shown, this embodiment provides a cover plate with a capacitive touch function, which includes a glass substrate 100, a transparent conductive layer 200 disposed on the glass substrate 100, a nanocomposite coating 300 covering the transparent conductive layer 200, a black frame layer 400 disposed at the edge of the glass substrate 100, and a silver paste lead 500 electrically connected to the transparent conductive layer 200;

[0041] Furthermore, an insulating layer 600 is provided over the silver paste leads 500 and the black frame layer 400. This insulating layer 600 can be formed using materials such as UV-curable epoxy resin by screen printing or spraying. The insulating layer 600 protects the silver paste leads 500 and the transparent conductive layer 200 from corrosion or damage, and improves the reliability of the cover.

[0042] The transparent conductive layer 200 includes a plurality of metal lines, which are interconnected to form a grid structure. The grid structure has a line width of 1 μm to 5 μm and a line spacing of 50 μm to 200 μm.

[0043] The nanocomposite coating 300 is composed of nanoparticles and organic resin, and the thickness of the nanocomposite coating 300 is 100nm-1μm;

[0044] The black frame layer 400 is printed by mixed black ink, and the mixed black ink contains black pigment and resin.

[0045] Specifically, in this embodiment, the glass substrate 100 is made of 0.5 mm thick soda-lime glass. The glass substrate 100 undergoes pre-treatment, such as cleaning and polishing, to ensure surface cleanliness and smoothness, providing a good foundation for subsequent processes. The size of the glass substrate 100 can be adjusted based on actual application requirements. In this embodiment, the cover plate has dimensions of approximately 140 mm x 70 mm.

[0046] Specifically, in this embodiment, the transparent conductive layer 200 is prepared by inkjet printing and comprises a silver nanowire grid structure having a hexagonal shape, a line width of 2 μm, and a line spacing of 100 μm.

[0047] The silver nanowire ink consists of 70% silver nanowires by weight, 5% dispersant by weight, and 25% solvent by weight. The inkjet printing parameters are as follows: nozzle temperature of 60°C, jet pressure of 20 kPa, jet frequency of 1 kHz, and jet spacing of 20 μm. These parameters ensure uniform distribution of the silver nanowires, forming a high-quality transparent conductive layer 200.

[0048] Specifically, in this embodiment, a nanocomposite coating 300 is applied to the transparent conductive layer 200 using a spin coating method. This coating is composed of 60% by weight SiO2 nanoparticles with a particle size of 50 nm and 40% by weight acrylic resin, with a thickness of 200 nm. The spin coating parameters are as follows: a spin speed of 3000 rpm and a coating time of 30 seconds. This coating improves the wear resistance and scratch resistance of the cover plate while maintaining high light transmittance.

[0049] The black frame layer 400 is located at the edge of the glass substrate 100 and is formed by screen printing a mixed black ink. This mixed black ink is composed of 70% by weight of carbon black pigment and 30% by weight of silicone resin. The ink viscosity is 50 cps, and the screen mesh is 300 mesh. The black frame layer 400 is 2 mm wide, ensuring sufficient light-shielding performance and providing a good connection with the rest of the cover.

[0050] Silver paste leads 500 are screen-printed on the black frame layer 400. These leads 500 connect to the metal grid of the transparent conductive layer 200 and are used to connect to the FPC. The silver paste has a solid content of 75%, a screen mesh of 200, and a printing thickness of 50 μm.

[0051] The cover plate with capacitive touch function provided in this embodiment uses silver nanowires as the material of the metal grid. Silver has excellent conductivity, so that the transparent conductive layer 200 can maintain a low square resistance even at a finer line width and a larger line spacing, thereby ensuring the high touch sensitivity of the cover plate. The hexagonal grid structure can maximize the transmittance at the same line width and line spacing. The nanocomposite coating 300 composed of SiO2 nanoparticles and acrylic resin takes into account both hardness and flexibility, improves the wear resistance and scratch resistance of the cover plate, and extends the service life. The black frame layer 400 formed by printing with a carbon black / silicone resin mixed ink has good light-shielding properties, and the silicone resin also ensures good adhesion to the glass substrate 100. The inkjet printing and spin coating processes are also relatively mature and suitable for large-scale production. The cover plate of this embodiment has the advantages of high performance, low cost and easy manufacturing.

[0052] Example 2

[0053] like Figure 1 As shown, this embodiment provides a cover plate with a capacitive touch function, which includes a glass substrate 100, a transparent conductive layer 200 disposed on the glass substrate 100, a nanocomposite coating 300 covering the transparent conductive layer 200, a black frame layer 400 disposed at the edge of the glass substrate 100, and a silver paste lead 500 electrically connected to the transparent conductive layer 200;

[0054] The transparent conductive layer 200 includes a plurality of metal lines, which are interconnected to form a grid structure. The grid structure has a line width of 1 μm to 5 μm and a line spacing of 50 μm to 200 μm.

[0055] The nanocomposite coating 300 is composed of nanoparticles and organic resin, and the thickness of the nanocomposite coating 300 is 100nm-1μm;

[0056] The black frame layer 400 is printed by mixed black ink, and the mixed black ink contains black pigment and resin.

[0057] Furthermore, an insulating layer 600 is included, and the insulating layer 600 covers the silver paste lead 500 and the black frame layer 400 .

[0058] In this embodiment, 0.7 mm thick flexible ultra-thin glass is used.

[0059] The transparent conductive layer 200 is made of copper alloy nanowires, using flexographic printing to form a square grid structure on the glass substrate 100. The line width is 3 μm and the line spacing is 150 μm. To prevent copper oxidation, the surface is passivated after printing to form a protective oxide layer.

[0060] The nanocomposite coating 300 is a mixture of 20 nm Al2O3 nanoparticles and epoxy resin, and is sprayed to form a protective coating with a thickness of 150 nm. The spraying pressure is 0.3 MPa and the spraying distance is 20 cm.

[0061] The black frame layer 400 is made of black ink prepared by mixing graphite powder and acrylic resin, and is formed on the edge of the glass substrate 100 by screen printing. In order to improve the bonding strength between the black frame and the substrate, the edge of the glass substrate 100 is plasma treated before printing.

[0062] The silver paste lead 500 is coated on the black frame layer 400 by dispensing silver paste and is connected to the transparent conductive layer 200 .

[0063] The cover plate with capacitive touch function provided in this embodiment adopts copper alloy nanowires and flexographic printing technology to reduce the manufacturing cost of the transparent conductive layer 200. Flexographic printing is suitable for flexible substrates and matches the 0.7 mm thick flexible ultra-thin glass substrate 100, which can realize the flexibility of the cover plate. The combination of Al2O3 nanoparticles and epoxy resin gives the protective coating higher hardness and wear resistance. The mixed ink of graphite powder and acrylic resin is low in cost, and plasma treatment enhances the bonding strength between the ink and the substrate, thereby improving the stability of the black frame layer 400. The dispensing process can precisely control the position of the silver paste. The cover plate of this embodiment has the advantages of low cost, high flexibility and good reliability, and is particularly suitable for cost-sensitive flexible display applications.

[0064] Example 3

[0065] like Figure 1As shown, this embodiment provides a cover plate with a capacitive touch function, which includes a glass substrate 100, a transparent conductive layer 200 disposed on the glass substrate 100, a nanocomposite coating 300 covering the transparent conductive layer 200, a black frame layer 400 disposed at the edge of the glass substrate 100, and a silver paste lead 500 electrically connected to the transparent conductive layer 200;

[0066] The transparent conductive layer 200 includes a plurality of metal lines, which are interconnected to form a grid structure. The grid structure has a line width of 1 μm to 5 μm and a line spacing of 50 μm to 200 μm.

[0067] The nanocomposite coating 300 is composed of nanoparticles and organic resin, and the thickness of the nanocomposite coating 300 is 100nm-1μm;

[0068] The black frame layer 400 is printed by mixed black ink, and the mixed black ink contains black pigment and resin.

[0069] Furthermore, an insulating layer 600 is included, and the insulating layer 600 covers the silver paste lead 500 and the black frame layer 400 .

[0070] In this embodiment, the glass substrate 100 is made of chemically tempered high-aluminum silicate glass with a thickness of 1 mm to improve the strength of the substrate.

[0071] The transparent conductive layer 200 is made of silver nanowires and is formed on the glass substrate 100 through photolithography. The line width is 1 μm and the line spacing is 50 μm. The photolithography process uses ultraviolet lithography, and the mask pattern accuracy is 0.5 μm.

[0072] Nanocomposite coating 300 utilizes a mixture of 80nm TiO2 nanoparticles and polyurethane resin. Silane coupling agents are used to modify the TiO2 surface, improving its compatibility with the polyurethane matrix. The silane coupling agent imparts polymer groups to the TiO2 surface, improving its compatibility with polyurethane. A 500nm thick protective coating is formed by dip coating at a speed of 5mm / s and a pull-out speed of 2mm / s.

[0073] The black frame layer 400 is made of a black ink mixed with carbon black and silicone resin, with a small amount of black iron oxide added to improve light-shielding properties. The black frame layer 400 is formed on the edge of the glass substrate 100 by screen printing and then baked at high temperature to enhance the adhesion of the ink to the substrate.

[0074] The silver paste lead 500 is prepared on the black frame layer 400 by inkjet printing and is connected to the transparent conductive layer 200 .

[0075] The cover plate with capacitive touch function provided in this embodiment adopts a high-aluminum silicate glass substrate 100 and a photolithography process, which has higher preparation precision and higher touch cover performance. High-aluminum silicate glass has higher strength and chemical corrosion resistance, which can greatly improve the durability of the cover plate. The photolithography process can achieve extremely fine line width and line spacing, thereby ensuring high touch accuracy while having high transmittance. TiO2 nanoparticles are compounded with polyurethane resin, and TiO2 is modified with a silane coupling agent to improve compatibility. The coating formed has excellent wear resistance and scratch resistance. The carbon black / silicone resin mixed ink with black iron oxide is added to further improve the light-shielding performance of the black frame layer 400. High-temperature baking enhances the adhesion of the ink to the substrate and improves the reliability of the black frame layer 400. The cover plate of this embodiment has the advantages of high precision, high performance and high reliability, and is suitable for high-end electronic products.

[0076] Example 4

[0077] like Figure 1 As shown, this embodiment provides a cover plate with a capacitive touch function, which includes a glass substrate 100, a transparent conductive layer 200 disposed on the glass substrate 100, a nanocomposite coating 300 covering the transparent conductive layer 200, a black frame layer 400 disposed at the edge of the glass substrate 100, and a silver paste lead 500 electrically connected to the transparent conductive layer 200;

[0078] The transparent conductive layer 200 includes a plurality of metal lines, which are interconnected to form a grid structure. The grid structure has a line width of 1 μm to 5 μm and a line spacing of 50 μm to 200 μm.

[0079] The nanocomposite coating 300 is composed of nanoparticles and organic resin, and the thickness of the nanocomposite coating 300 is 100nm-1μm;

[0080] The black frame layer 400 is printed by mixed black ink, and the mixed black ink contains black pigment and resin.

[0081] Furthermore, an insulating layer 600 is included, and the insulating layer 600 covers the silver paste lead 500 and the black frame layer 400 .

[0082] In this embodiment, the glass substrate 100 is made of 0.8 mm thick soda lime glass.

[0083] The transparent conductive layer 200 is made of nickel nanowires and is formed on the glass substrate 100 using nanoimprint technology. The hexagonal grid structure of the transparent conductive layer 200 is 4 μm wide and 200 μm apart. The nanoimprint process uses soft imprint technology and the mold material is PDMS.

[0084] The nanocomposite coating 300 is a mixture of ZrO2 nanoparticles with a particle size of 100 nm and acrylic resin, and a protective coating with a thickness of 300 nm is formed by blade coating.

[0085] The black frame layer 400 is formed by mixing black cobalt oxide and polyurethane resin to prepare black ink, and the black frame layer 400 is formed on the edge of the glass substrate 100 by screen printing.

[0086] Silver paste leads 500 are prepared on the black frame layer 400 by screen printing and connected to the transparent conductive layer 200. In order to improve the contact resistance between the silver paste and the transparent conductive layer 200, the transparent conductive layer 200 is partially plasma treated before printing the silver paste.

[0087] The cover plate with capacitive touch function provided in this embodiment adopts nickel nanowires and nanoimprint technology to explore a low-cost, high-efficiency preparation method. Nanoimprint technology can achieve high-throughput, low-cost production and is suitable for large-scale manufacturing. The coating composed of ZrO2 nanoparticles and acrylic resin provides a certain wear resistance and anti-scratch protection. The mixed ink of black cobalt oxide and polyurethane resin can form a black frame layer 400 with good light-shielding performance. Plasma treatment enhances the adhesion between the silver paste and the nickel nanowires, reduces the contact resistance, and improves the touch sensitivity. The cover plate of this embodiment has the advantages of low cost and high efficiency in manufacturing while ensuring certain performance, and is suitable for cost-sensitive mass consumer electronic products.

[0088] Unless otherwise specifically stated, the relative arrangement, numerical expression and numerical value of the parts and steps set forth in these embodiments do not limit the scope of the application. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a restriction. Therefore, other examples of exemplary embodiments can have different values. It should be noted that: similar reference numerals and letters represent similar items in the accompanying drawings below, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in the accompanying drawings subsequently.

[0089] In addition, it should be noted that the use of terms such as "first" and "second" for limitation is only for the convenience of distinction. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of this application.

[0090] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A cover with capacitive touch function, characterized in that: The invention comprises a glass substrate (100), a transparent conductive layer (200) arranged on the glass substrate (100), a nanocomposite material coating (300) covering the transparent conductive layer (200), a black frame layer (400) arranged at the edge of the glass substrate (100), and a silver paste lead (500) electrically connected to the transparent conductive layer (200); The transparent conductive layer (200) comprises a plurality of metal lines, the plurality of metal lines are interconnected to form a grid structure, the line width of the grid structure is 1 μm-5 μm, and the line spacing is 50 μm-200 μm; The nanocomposite coating (300) is composed of nanoparticles and an organic resin, and the thickness of the nanocomposite coating (300) is 100 nm-1 μm; The black frame layer (400) is printed by mixed black ink, and the mixed black ink contains black pigment and resin.

2. The cover plate according to claim 1, wherein: The metal material is selected from silver, copper, nickel, silver alloy, copper alloy and nickel alloy.

3. The cover plate according to claim 1, wherein: The grid structure is in the shape of a square, a diamond or a hexagon.

4. The cover plate according to claim 1, wherein: The nanoparticles are SiO2, Al2O3, TiO2 or ZrO2; The organic resin is acrylic resin, epoxy resin or polyurethane.

5. The cover plate according to claim 1, wherein: The black pigment is carbon black, graphite, black iron oxide or black cobalt oxide; The resin is acrylic resin, epoxy resin, polyurethane or silicone resin.

6. The cover plate according to claim 1, wherein: The transparent conductive layer (200) is prepared by inkjet printing, screen printing, photolithography or nanoimprinting.

7. The cover plate according to claim 1, wherein: The nanocomposite coating (300) is prepared by spray coating, spin coating, dip coating or blade coating.

8. The cover plate according to claim 1, wherein: The silver paste lead (500) is prepared by screen printing, inkjet printing or dispensing, and is connected to the transparent conductive layer (200).

9. The cover plate according to claim 1, wherein: The metal material is silver nanowires, the grid structure is hexagonal, the line width is 2 μm, and the line spacing is 100 μm.

10. The cover plate according to claim 1, wherein: The metal material is silver; The grid structure is hexagonal, with a line width of 2 μm and a line spacing of 100 μm; The nanoparticles are SiO2, the organic resin is acrylic resin, and the thickness of the nanocomposite coating (300) is 200 nm; The black pigment is carbon black, and the resin is silicone resin.

Images