Capacitive touch screen, preparation method thereof and electronic equipment

Abstract

The invention provides a capacitive touch screen, a preparation method of the capacitive touch screen and electronic equipment. The capacitive touch screen comprises a protective layer, a blocking layer, a first bonding layer, an induction circuit layer, a first base material and a driving circuit layer which are sequentially arranged. The barrier layer self-protection layer comprises a second bonding layer, a second base material, a first transition film and a second diaphragm which are arranged in sequence; the transmissivity of the first transition film is larger than 98%, and the second diaphragm is made of silicon oxide. Through the structural design, penetration of Sn, Na and H2O ions can be blocked, so that the conducting layer of the conducting film is prevented from being attacked, and the destructive effect of the conducting layer can be delayed.

Description

Technical Field

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

[0002] Commercial capacitive touch screens are used in large-size interactive displays, generally defined as 45 inches and above. Due to protection and safety needs, physical tempered glass (such as soda-lime glass) is generally used as the surface protective layer.

[0003] Soda-lime glass is divided into an air side and a tin side during glass production. The flat tin side is used to bond with the conductive film layer. The Sn ions on the surface of the physical tempered glass and Na will penetrate the OCA optical glue to reach the conductive (metal) layer under the action of water vapor. These particles attack the indium tin oxide conductive film (ITO conductive film) or other conductive alloy particles such as Ag, Al, Zr, etc., causing the oxide or metal conductive layer to crack and peel off, and functional failure.

[0004] The optical transparent adhesive used in commercial display touch screens has the property of absorbing water. Under high temperature and high humidity conditions, it absorbs water and accelerates the movement of Sn particles and Na particles in the physical tempered glass to the conductive metal layer, destroying the conductive film metal layer structure and causing an open circuit. It also causes a short circuit between the conductive film metal conductive layer circuits under hygroscopic conditions. Under high temperature and high humidity conditions, the effects of the above Sn and Na ions increase significantly.

[0005] Therefore, it is necessary to develop new commercial display touch screen structures and preparation processes to solve the above problems. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention provides a capacitive touch screen and a preparation method and an electronic device, which can effectively prevent the short circuit between the conductive film and metal conductive layer circuits under high temperature and high humidity power-on conditions, and the preparation process is simple. The barrier layer can be directly attached to the protective layer with high attachment firmness and excellent performance.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a capacitive touch screen, the capacitive touch screen comprising a protective layer, a barrier layer, a first adhesive layer, a sensing circuit layer, a first substrate and a driving circuit layer arranged in sequence;

[0009] The barrier layer self-protection layer comprises a second adhesive layer, a second substrate, a first transition film and a second diaphragm arranged in sequence;

[0010] The transmittance of the first transition film is greater than 98%, and the material of the second diaphragm is silicon oxide.

[0011] The present invention selects a material with a transmittance greater than 98% as the first transition film, and selects silicon oxide as the second diaphragm. The two interact with each other, wherein the transition film can improve the coating uniformity and adhesion of silicon oxide, thereby improving the water vapor isolation ability of the final barrier layer. The first transition film with high transmittance is conducive to ensuring the optical performance of the capacitive touch screen and can effectively achieve the transition between silicon oxide and the second substrate, ensuring that the film layer of silicon oxide does not peel off.

[0012] Preferably, the material of the first transition film includes resin-based organic matter and / or inorganic matter.

[0013] Preferably, the resinous organic matter includes acrylic resin and / or polyurethane resin.

[0014] Preferably, the inorganic substance includes oxides and / or nitrides.

[0015] Preferably, the oxide comprises aluminum oxide.

[0016] Preferably, the nitride comprises silicon nitride.

[0017] Preferably, when the first transition film is a resin-based organic material, the thickness of the first transition film is 4 to 10 μm, for example, it can be 4 μm, 4.7 μm, 5.4 μm, 6 μm, 6.7 μm, 7.4 μm, 8 μm, 8.7 μm, 9.4 μm or 10 μm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0018] Preferably, when the first transition film is an inorganic material, the thickness of the first transition film is 10 to 20 nm, for example, it can be 10 nm, 12 nm, 13 nm, 14 nm, 15 nm, 16 nm, 17 nm, 18 nm, 19 nm or 20 nm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0019] Preferably, the thickness of the second diaphragm is 60 to 80 nm, for example, it can be 60 nm, 63 nm, 65 nm, 67 nm, 69 nm, 72 nm, 74 nm, 76 nm, 78 nm or 80 nm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0020] Preferably, the material of the second diaphragm contains both silicon dioxide and silicon monoxide.

[0021] Preferably, the content of silicon monoxide in the silicon oxide is 0.5-10wt%, for example, it can be 0.5wt%, 1wt%, 1.5wt%, 2.0wt%, 2.5wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt% or 10wt%, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0022] Compared with using other substances as barrier layers, silicon oxide has the advantages of low cost and excellent performance. However, since silicon oxide will deposit silicon monoxide in addition to silicon dioxide during the deposition process, the present invention preferably controls the silicon monoxide content in the range of 0.5 to 10 wt% during the deposition process, so as to better improve the protective performance. When the silicon monoxide content is too high, the water vapor barrier performance is significantly reduced. When it is necessary to control the silicon monoxide content to be lower than 0.5 wt%, the manufacturing cost is significantly increased and the degree of integration with the film layer is reduced.

[0023] Preferably, the barrier layer further comprises a silicon nitride layer disposed on the second diaphragm.

[0024] Preferably, the thickness of the silicon nitride layer is 10 to 20 nm, for example, 10 nm, 11 nm, 12 nm, 13 nm, 14 nm, 15 nm, 18 nm, 19 nm or 20 nm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0025] Preferably, the 24h water vapor transmission efficiency of the barrier layer is less than 10 -3 g / m 2 .

[0026] Preferably, the material of the second substrate includes PET or TAC.

[0027] In the present invention, PET refers to polyethylene terephthalate, and TAC refers to triacetyl cellulose.

[0028] Preferably, the thickness of the second substrate is 50-125 μm, for example, it can be 50 μm, 55 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 105 μm, 110 μm, 115 μm, 120 μm or 125 μm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0029] Preferably, the material of the second adhesive layer includes solid high-transmittance optical glue, preferably acrylic solid high-transmittance optical glue.

[0030] Preferably, the thickness of the second adhesive layer is 25 to 125 μm, for example, it can be 25 μm, 37 μm, 48 μm, 59 μm, 70 μm, 81 μm, 92 μm, 103 μm, 114 μm or 125 μm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0031] Preferably, the protective layer is protective glass. The protective glass of the present invention is preferably tempered glass.

[0032] Preferably, the thickness of the protective layer is 1 to 3 mm, for example, 1 mm, 1.5 mm, 1.8 mm, 2.0 mm, 2.5 mm, 2.8 mm or 3.0 mm, but is not limited to the listed values, and other values ​​not listed within the range are also applicable.

[0033] Preferably, the material of the first adhesive layer is optically transparent adhesive, preferably OCA (special adhesive for bonding transparent optical elements).

[0034] Preferably, the thickness of the first adhesive layer is 50 to 175 μm, for example, it can be 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 100 μm, 110 μm, 120 μm, 150 μm or 175 μm, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0035] Preferably, the material of the first substrate includes any one of PET, GLASS or TAC.

[0036] Preferably, the thickness of the first substrate is 50-125 μm, for example, it can be 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 100 μm, 110 μm, 120 μm, 125 μm, etc., but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0037] In a second aspect, the present invention provides a method for preparing the capacitive touch screen according to the first aspect, the method comprising the following steps:

[0038] (1) The protective layer is cleaned to obtain a cleaned protective layer;

[0039] (2) attaching the second adhesive layer in the barrier layer to the cleaned protective layer, and performing roller pressing and degassing treatment to composite the barrier layer and the protective layer to obtain a first intermediate screen;

[0040] (2) A first adhesive layer, a sensing circuit layer, a first substrate and a driving circuit layer are sequentially arranged on the first intermediate screen to obtain the capacitive touch screen.

[0041] The present invention preferably adopts a method of directly adhering the barrier layer to the protective layer. Compared with arranging the barrier layer material layer by layer on the protective layer, the method of the present invention is simpler to operate and can effectively avoid adverse effects on the protective layer during the manufacturing process.

[0042] It is worth noting that the present invention is aimed at capacitive touch screens with a thickness of 1 to 3 mm and a size of 45 inches or above, which are difficult to be manufactured by layer-by-layer lamination like small screens, so the above method is used for lamination.

[0043] Preferably, the cleaning in step (1) includes spray cleaning.

[0044] Preferably, the spray density of the spray cleaning is 0.1-0.3 kg / cm 2 , for example, it can be 0.1kg / cm 2 , 0.2kg / cm 2 , 0.2kg / cm 2 , 0.2kg / cm 2 , 0.2kg / cm 2 , 0.3kg / cm 2 , 0.3kg / cm 2 , 0.3kg / cm 2 , 0.3kg / cm 2 or 0.3kg / cm 2 The above values ​​are not limited to the above values, and other values ​​not listed in the above values ​​are also applicable.

[0045] Preferably, the temperature of the spray cleaning is 35-40°C, for example, it can be 35°C, 35.6°C, 36.2°C, 36.7°C, 37.3°C, 37.8°C, 38.4°C, 38.9°C, 39.5°C or 40°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0046] Preferably, the pH of the spray cleaning liquid is 4-7, for example, 4, 4.4, 4.7, 5, 5.4, 5.7, 6, 6.4, 6.7 or 7, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0047] Preferably, the roller pressing pressure in step (2) is 0.3-0.6 MPa, for example, it can be 0.3 MPa, 0.34 MPa, 0.37 MPa, 0.4 MPa, 0.44 MPa, 0.47 MPa, 0.5 MPa, 0.54 MPa, 0.57 MPa or 0.6 MPa, but is not limited to the listed values, and other values ​​not listed within the range are also applicable.

[0048] Preferably, the temperature of the degassing treatment is 40-60°C, for example, it can be 40°C, 43°C, 45°C, 47°C, 49°C, 52°C, 54°C, 56°C, 58°C or 60°C, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0049] Preferably, the degassing treatment time is 10 to 30 minutes, for example, it can be 10 minutes, 13 minutes, 15 minutes, 17 minutes, 19 minutes, 22 minutes, 24 minutes, 26 minutes, 28 minutes or 30 minutes, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0050] The key in the present invention is the degree of adhesion between the barrier layer and the protective layer, which depends on two aspects. On the one hand, the material selection of the barrier layer is more critical. By selecting a second adhesive layer with suitable performance and material, it can have a better adhesion with the protective layer. On the other hand, it depends on the selection of attachment parameters during the attachment process, among which the pressure of the roller pressing and the temperature of the degassing treatment are more critical. When the pressure of the roller pressing is too large, it is easy to cause damage to the barrier layer and the protective layer. When the pressure of the roller pressing is too small, the pressure of the attachment of the two is too small, the attachment strength is small, and the degree of adhesion is significantly reduced. The present invention combines the material of the second adhesive layer and the process conditions of the attachment, thereby arranging a barrier layer with excellent performance on the back of the protective layer, thereby improving the waterproof performance.

[0051] It is worth mentioning that the material selection of other layers in the barrier layer of the present invention needs to consider the excellent barrier performance against water vapor on the one hand, and on the other hand, the material will not deform, melt or produce large stress leading to cracking under the pressure and temperature conditions of attachment. Based on the above considerations, the present invention has developed the material composition of the above barrier layer, which can achieve the effect of attachment and significantly improve the water barrier performance, especially under high humidity and high temperature conditions, it can block Sn and Na ions.

[0052] Preferably, the degassing process comprises: applying pressure to perform degassing.

[0053] Preferably, the applied pressure is in the range of 0.5 to 0.7 MPa, for example, it may be 0.5 MPa, 0.52 MPa, 0.53 MPa, 0.54 MPa, 0.55 MPa, 0.58 MPa, 0.6 MPa, 0.62 MPa, 0.65 MPa, 0.68 MPa or 0.7 MPa, but is not limited to the listed values, and other unlisted values ​​within the range are equally applicable.

[0054] Preferably, the method for preparing the barrier layer includes: setting a first transition film on one side of a second substrate; depositing silicon oxide on a side of the first transition film away from the second substrate to obtain a second membrane; and setting a second adhesive layer on the other side of the second substrate to obtain the barrier layer.

[0055] Preferably, the method of depositing silicon oxide comprises magnetron sputtering or chemical vapor deposition.

[0056] Preferably, the pressure range of the magnetron sputtering is ≤0.01 mbar, for example, it can be 0.01 mbar, 0.008 mbar, 0.007 mbar, 0.006 mbar, 0.005 mbar or 0.004 mbar, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0057] Preferably, the magnetron sputtering uses a high-purity silicon target with a purity of ≥99.99%.

[0058] Preferably, the power of the magnetron sputtering is 18-20 kW, for example, it can be 18 kW, 18.2 kW, 18.5 kW, 18.9 kW, 19.0 kW, 19.2 kW, 19.3 kW, 19.5 kW, 19.8 kW or 20.0 kW.

[0059] Preferably, the magnetron sputtering is performed in an atmosphere of a combination of argon and oxygen.

[0060] Preferably, the ratio of argon flow rate to oxygen flow rate in the magnetron sputtering is 200-300sccm:80-150sccm, for example, it can be 200sccm:80sccm, 250sccm:80sccm, 260sccm:90sccm, 200sccm:100sccm, 250sccm:110sccm or 300sccm:150sccm, etc.

[0061] In a third aspect, the present invention provides an electronic device, wherein the electronic device comprises the capacitive touch screen described in the first aspect.

[0062] The electronic device provided by the third aspect of the present invention has excellent waterproof performance and a long service life.

[0063] The present invention has no special requirements for the electronic device, and any electronic device containing a capacitive touch screen known to those skilled in the art can be used. The commercial capacitive touch screen of the present invention is preferably used in the field of large-size interactive display, generally defined as 45 inches and above. Due to protection and safety needs, physical tempered glass (such as soda-lime glass) is generally used as a surface protective layer, and the thickness is relatively thick, generally 1 to 3 mm.

[0064] Compared with the prior art, the present invention has at least the following beneficial effects:

[0065] (1) The capacitive touch screen provided by the present invention has a simple preparation process and excellent moisture and high temperature resistance. Under high temperature and high humidity conditions, the water vapor barrier effect is still good. The water vapor transmission rate is ≤7*10 under the conditions of 38°C and 90% RH for 24 hours. -3 g / m 2 ·24h, at 85℃, 85% humidity, the service life can reach more than 1000h;

[0066] (2) The method for preparing the capacitive touch screen provided by the present invention can directly attach the barrier layer to the protective layer. The preparation method is simple and conducive to industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 Schematic diagram of a capacitive touch screen provided in Embodiment 1 of the present invention.

[0068] Figure 2 Schematic diagram of the barrier layer in Example 1 of the present invention.

[0069] Figure 3 Schematic diagram of a capacitive touch screen provided in Comparative Example 1 of the present invention.

[0070] In the figure: 1, protective layer; 2, barrier layer; 21, second bonding layer; 22, second substrate; 23, first transition film; 24, second diaphragm; 3, first bonding layer; 4, sensing circuit layer; 5, first substrate; 6, driving circuit layer. DETAILED DESCRIPTION

[0071] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0072] The present invention is further described in detail below. However, the following examples are only simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

[0073] It should be understood that, in the description of the present invention, the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0074] It should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "disposed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0075] Example 1

[0076] This embodiment provides a capacitive touch screen, such as Figures 1-2 As shown, the capacitive touch screen includes a protective layer, a barrier layer 2, a first adhesive layer 3, a sensing circuit layer 4, a first substrate 5 and a driving circuit layer 6 arranged in sequence; the barrier layer 2 includes a second adhesive layer 21, a second substrate 22, a first transition film 23 and a second diaphragm 24 arranged in sequence; the transmittance of the first transition film 23 is greater than 98%, and the material of the second diaphragm 24 is silicon oxide.

[0077] The first transition film 23 is made of silicon nitride.

[0078] The thickness of the first transition film 23 is 15 nm.

[0079] The thickness of the second diaphragm 24 is 70 nm. The material of the second diaphragm 24 contains both silicon dioxide and silicon monoxide. The thickness of silicon monoxide in the silicon oxide is 5.5%.

[0080] The material of the second substrate 22 includes PET. The thickness of the second substrate 22 is 125μm. The material of the second adhesive layer 21 is acrylic solid high-transmittance optical glue (specific brand DA980). The thickness of the second adhesive layer 21 is 125μm. The protective layer is protective glass (tempered glass). The thickness of the protective layer is 3mm. The material of the first adhesive layer 3 is OCA. The thickness of the first adhesive layer 3 is 125μm. The material of the first substrate 5 is PET. The thickness of the first substrate 5 is 125μm.

[0081] This embodiment also provides a method for preparing the capacitive touch screen, and the method comprises the following steps:

[0082] (1) The protective layer is sprayed and cleaned with a spray density of 0.2 kg / cm 2 , the temperature is 38°C, the pH of the liquid is 5.0, and a protective layer after cleaning is obtained;

[0083] (2) laminating the second adhesive layer in the barrier layer on the cleaned protective layer, and performing roller pressing at a pressure of 0.5 MPa and degassing treatment at 55° C. for 20 min under a pressure of 0.6 MPa to composite the barrier layer and the protective layer to obtain a first intermediate screen;

[0084] (2) A first adhesive layer, a sensing circuit layer, a first substrate and a driving circuit layer are sequentially arranged on the first intermediate screen to obtain the capacitive touch screen.

[0085] The preparation method of the barrier layer includes: setting a first transition film on one side of a second substrate; depositing silicon oxide on the side of the first transition film away from the second substrate to obtain a second diaphragm; and setting a second adhesive layer on the other side of the second substrate to obtain the barrier layer.

[0086] Specifically, the method for depositing silicon oxide is magnetron sputtering, which includes: in a vacuum environment less than 0.01mbar, using a high-purity silicon target with a purity greater than 99.99%, coating at a power of 20kW, an argon flow rate of 250sccm, and an oxygen flow rate of 110sccm, and the thickness of the silicon oxide is 70nm.

[0087] Example 2

[0088] The present embodiment provides a capacitive touch screen, which includes a protective layer, a barrier layer, a first adhesive layer, a sensing circuit layer, a first substrate and a driving circuit layer arranged in sequence; the barrier layer and the protective layer include a second adhesive layer, a second substrate, a first transition film and a second diaphragm arranged in sequence; the transmittance of the first transition film is greater than 98%, and the material of the second diaphragm is silicon oxide.

[0089] The material of the first transition film is silicon nitride.

[0090] The thickness of the first transition film is 20 nm.

[0091] The thickness of the second diaphragm is 60 nm. The material of the second diaphragm contains both silicon dioxide and silicon monoxide. The content of silicon monoxide in the silicon oxide is 4%.

[0092] The material of the second substrate includes TAC. The thickness of the second substrate is 50μm. The material of the second adhesive layer is acrylic solid high-transmittance optical glue (specific brand DA980). The thickness of the second adhesive layer is 125μm. The protective layer is protective glass (tempered glass). The thickness of the protective layer is 2mm. The material of the first adhesive layer is OCA (LUCIACSCS986). The thickness of the first adhesive layer is 175μm. The material of the first substrate is GLASS. The thickness of the first substrate is 1.0mm.

[0093] This embodiment also provides a method for preparing the capacitive touch screen, and the method comprises the following steps:

[0094] (1) The protective layer is sprayed and cleaned with a spray density of 0.3 kg / cm 2 , the temperature is 35°C, the pH value of the liquid is 7.0, and a protective layer after cleaning is obtained;

[0095] (2) laminating the second adhesive layer in the barrier layer on the cleaned protective layer, and subjecting the barrier layer and the protective layer to composite by roller pressing at a pressure of 0.6 MPa and degassing treatment at 40° C. at a pressure of 0.5 MPa for 30 min, thereby obtaining a first intermediate screen;

[0096] (2) A first adhesive layer, a sensing circuit layer, a first substrate and a driving circuit layer are sequentially arranged on the first intermediate screen to obtain the capacitive touch screen.

[0097] The preparation method of the barrier layer includes: setting a first transition film on one side of a second substrate; depositing silicon oxide on the side of the first transition film away from the second substrate to obtain a second diaphragm; and setting a second adhesive layer on the other side of the second substrate to obtain the barrier layer.

[0098] Specifically, the method for depositing silicon oxide is magnetron sputtering, which includes: in a vacuum environment less than 0.01mbar, using a high-purity silicon target with a purity greater than 99.99%, coating at a power of 19kW, an argon flow rate of 230sccm, and an oxygen flow rate of 120sccm, and the thickness of the silicon oxide is 60nm.

[0099] Example 3

[0100] The present embodiment provides a capacitive touch screen, which includes a protective layer, a barrier layer, a first adhesive layer, a sensing circuit layer, a first substrate and a driving circuit layer arranged in sequence; the barrier layer and the protective layer include a second adhesive layer, a second substrate, a first transition film and a second diaphragm arranged in sequence; the transmittance of the first transition film is greater than 99%, and the material of the second diaphragm is silicon oxide.

[0101] The material of the first transition film is acrylic resin (brand number SW02D-2).

[0102] The thickness of the first transition film is 4 μm.

[0103] The thickness of the second diaphragm is 60 nm. The material of the second diaphragm contains both silicon dioxide and silicon monoxide. The content of silicon monoxide in the silicon oxide is 4.5 wt%.

[0104] The material of the second substrate includes TAC. The thickness of the second substrate is 125μm. The material of the second adhesive layer is acrylic solid high-transmittance optical glue (specific brand DA980-125). The thickness of the second adhesive layer is 125μm. The protective layer is protective glass (tempered glass). The thickness of the protective layer is 3mm. The material of the first adhesive layer is OCA (LUCIACSCS986). The thickness of the first adhesive layer is 50μm. The material of the first substrate is PET. The thickness of the first substrate is 125μm.

[0105] This embodiment also provides a method for preparing the capacitive touch screen, and the method comprises the following steps:

[0106] (1) The protective layer is sprayed and cleaned with a spray density of 0.1 kg / cm 2 , the temperature is 40°C, the pH value of the liquid is 4.0, and a protective layer after cleaning is obtained;

[0107] (2) laminating the second adhesive layer in the barrier layer on the cleaned protective layer, and subjecting the barrier layer and the protective layer to composite by roller pressing at a pressure of 0.3 MPa and degassing treatment at 60° C. at a pressure of 0.7 MPa for 10 min, thereby obtaining a first intermediate screen;

[0108] (2) A first adhesive layer, a sensing circuit layer, a first substrate and a driving circuit layer are sequentially arranged on the first intermediate screen to obtain the capacitive touch screen.

[0109] The preparation method of the barrier layer includes: setting a first transition film on one side of a second substrate; depositing silicon oxide on the side of the first transition film away from the second substrate to obtain a second diaphragm; and setting a second adhesive layer on the other side of the second substrate to obtain the barrier layer.

[0110] Specifically, when the method for depositing silicon oxide is magnetron sputtering, the steps and process parameters of the magnetron sputtering include coating in a vacuum environment of less than 0.01 mbar, using a high-purity silicon target with a purity greater than 99.99%, at a power of 18 kW, an argon flow rate of 280 sccm, and an oxygen flow rate of 150 sccm, and the thickness of the silicon oxide is 60 nm.

[0111] Example 4

[0112] The present embodiment provides a capacitive touch screen, which includes a protective layer, a barrier layer, a first adhesive layer, a sensing circuit layer, a first substrate and a driving circuit layer arranged in sequence; the barrier layer and the protective layer include a second adhesive layer, a second substrate, a first transition film and a second diaphragm arranged in sequence; the transmittance of the first transition film is greater than 99%, and the material of the second diaphragm is silicon oxide.

[0113] The material of the first transition film is acrylic resin (brand number SW02D-2).

[0114] The thickness of the first transition film is 8 μm.

[0115] The thickness of the second diaphragm is 75nm. The material of the second diaphragm contains both silicon dioxide and silicon monoxide, and the content of silicon monoxide is 2wt%. The barrier layer also includes a silicon nitride layer arranged on the second diaphragm; the thickness of the silicon nitride layer is 15nm.

[0116] The material of the second substrate includes PET. The thickness of the second substrate is 100μm. The material of the second adhesive layer is acrylic solid high-transmittance optical glue (specific brand DA980-125). The thickness of the second adhesive layer is 55μm. The protective layer is protective glass (tempered glass). The thickness of the protective layer is 2mm. The material of the first adhesive layer is OCA (LUCIACSCS986). The thickness of the first adhesive layer is 35μm. The material of the first substrate is PET. The thickness of the first substrate is 100μm.

[0117] This embodiment also provides a method for preparing the capacitive touch screen, and the method comprises the following steps:

[0118] (1) The protective layer is sprayed and cleaned with a spray density of 0.15 kg / cm 2 , the temperature is 38°C, the pH of the liquid is 5.0, and a protective layer after cleaning is obtained;

[0119] (2) laminating the second adhesive layer in the barrier layer on the cleaned protective layer, and subjecting the barrier layer and the protective layer to composite by roller pressing at a pressure of 0.4 MPa and degassing treatment at 50° C. for 15 min at a pressure of 0.55 MPa, thereby obtaining a first intermediate screen;

[0120] (2) A first adhesive layer, a sensing circuit layer, a first substrate and a driving circuit layer are sequentially arranged on the first intermediate screen to obtain the capacitive touch screen.

[0121] The preparation method of the barrier layer includes: setting a first transition film on one side of a second substrate; depositing silicon oxide on the side of the first transition film away from the second substrate to obtain a second diaphragm; and setting a second adhesive layer on the other side of the second substrate to obtain the barrier layer.

[0122] Specifically, when the method for depositing silicon oxide is magnetron sputtering, the steps and process parameters of the magnetron sputtering include coating in a vacuum environment of less than 0.01 mbar, using a high-purity silicon target with a purity greater than 99.99%, at a power of 19 kW, an argon flow rate of 300 sccm, and an oxygen flow rate of 80 sccm, and the thickness of the silicon oxide is 75 nm. Example 5

[0123] This embodiment provides a capacitive touch screen. Except that the thickness of the second diaphragm is 10 nm, the rest of the capacitive touch screen is the same as that of the first embodiment, and will not be described in detail here.

[0124] Example 6

[0125] This embodiment provides a capacitive touch screen. Except that the thickness of the second diaphragm is 95 nm, the rest of the capacitive touch screen is the same as that of the first embodiment, and will not be described again.

[0126] Example 7

[0127] This embodiment provides a capacitive touch screen. The capacitive touch screen is the same as that of the first embodiment except that the content of silicon monoxide in the material of the second diaphragm reaches 15%, and the details are not described again.

[0128] Example 8

[0129] This embodiment provides a capacitive touch screen. The capacitive touch screen is the same as that of Embodiment 1 except that the roller pressing pressure in the preparation method is 0.9 MPa, and the details are not described again.

[0130] Example 9

[0131] This embodiment provides a capacitive touch screen. Except that the rolling pressure of the roller is 0.1 MPa, the rest of the capacitive touch screen is the same as that of the first embodiment, and will not be described in detail here.

[0132] Example 10

[0133] This embodiment provides a capacitive touch screen. Except that no pressure is applied during the degassing process, the capacitive touch screen is the same as that of the first embodiment, and will not be described in detail here.

[0134] Embodiment 11

[0135] This embodiment provides a capacitive touch screen. The capacitive touch screen is the same as that of Embodiment 1 except that the temperature of the degassing treatment is 30° C., and details thereof will not be repeated herein.

[0136] Comparative Example 1

[0137] This comparative example provides a capacitive touch screen, such as Figure 3 As shown, the capacitive touch screen is the same as that of the first embodiment except that the barrier layer 2 is not provided, and the details are not repeated here.

[0138] Comparative Example 2

[0139] This comparative example provides a capacitive touch screen. Except that the first transition film is not provided in the barrier layer, the other aspects of the capacitive touch screen are the same as those of Example 1, and will not be described in detail herein.

[0140] Comparative Example 3

[0141] This comparative example provides a capacitive touch screen. Except that the second diaphragm is not provided in the barrier layer, the other aspects of the capacitive touch screen are the same as those of Example 1, and will not be described in detail herein.

[0142] Comparative Example 4

[0143] This comparative example provides a capacitive touch screen, which is the same as Example 1 except that the first transition film is not provided in the barrier layer and is a PP film, and the rest is not described again.

[0144] Comparative Example 5

[0145] This comparative example provides a capacitive touch screen. The capacitive touch screen is the same as that of Example 1 except that the second diaphragm is made of aluminum oxide, and the details are not described again.

[0146] It is worth mentioning that although aluminum oxide has good water-blocking properties, its cost is relatively high and the optical properties of the product have changed significantly, making it difficult to use in capacitive touch screens. Its industrial application is not as extensive as that of silicon oxide barrier films.

[0147] Test method: Using GB / T1037-2021, test the water vapor transmission rate for 24 hours at 38°C and 90% RH; test the life of the capacitive touch screen under power-on conditions at 85°C and 85% humidity (based on the conductive layer not peeling off).

[0148] The test results of the above embodiments and comparative examples are shown in Table 1.

[0149] Table 1

[0150]

[0151]

[0152] From Table 1, we can see the following points:

[0153] (1) It can be seen from Examples 1 to 4 that the capacitive touch screen provided by the present invention has an excellent water vapor barrier effect. Combined with the lamination process, it can achieve a 24h water vapor transmission efficiency of less than or equal to 7*10 -3 g / m 2 ·24h, at 85℃, 85% humidity, the service life can reach more than 1000h;

[0154] (2) Combining Example 1 and Examples 5 to 6, it can be seen that the thickness of the silicon oxide in Example 5 is only 10 nm, resulting in no significant improvement in water resistance, which is about 2 g / m 2 24h, no water barrier, while in Example 6, after the thickness of the second diaphragm reaches 80nm or more, the water barrier does not change compared with Example 1, but in Example 6, due to the excessive thickness of the second diaphragm, the lamination effect is poor during the roll lamination process, and the lamination success rate drops to 75%. This shows that the present invention significantly improves the water barrier and can ensure the lamination success rate of 100% by controlling the thickness of the silicon oxide in the second diaphragm within a specific range, which is conducive to industrial production;

[0155] (3) It can be seen from Example 1 and Example 7 that in Example 7, due to the excessively high content of silicon monoxide, the water barrier performance is significantly reduced under the same thickness condition. This shows that the present invention significantly improves the water barrier performance of the silicon oxide as a diaphragm by controlling the content of silicon monoxide in the silicon oxide.

[0156] (4) Combining Example 1 and Examples 8 to 10, it can be seen that the increase in the laminating pressure in Example 8 has no effect on the waterproofness of the product, and the water barrier is equivalent to that of Example 1, but not only the service life of the laminating roller is reduced, but the success rate of film laminating is also reduced to 85%. In Examples 9 to 10, due to the generation of interlayer bubbles on the laminating surface, water vapor will be deposited on the interface of the bubble area. Although the water barrier is equivalent to that of Example 1, the life of the double 85 test is significantly reduced. This shows that the present invention significantly improves the temperature and humidity resistance life of the capacitive touch screen by adopting pressurized lamination and controlling the pressure within a reasonable range;

[0157] (5) It can be seen from Example 1 and Example 11 that the temperature of the degassing treatment in Example 11 is too low, resulting in bubbles on the bonding surface that are not completely eliminated. Although the water barrier is equivalent to that of Example 1, the life of the double 85 test is significantly reduced; and when the temperature of the degassing treatment is too high, the energy consumption is significantly increased and the cost is high. This shows that the present invention significantly improves the temperature and humidity resistance life of the capacitive touch screen by controlling the temperature of the degassing treatment within a specific range;

[0158] (6) It can be seen from Example 1 and Comparative Examples 1 to 3 that Comparative Examples 1 and 3 do not have water barrier properties, and the adhesion of the second diaphragm layer in Comparative Example 2 is reduced, and the water barrier property is significantly reduced compared with Example 1. This shows that the present invention significantly extends the temperature and humidity resistance life by adopting a capacitive touch screen with a special structure;

[0159] (7) It can be seen from Example 1 and Comparative Example 4 that although only the material of the first transition film is replaced in Comparative Example 4, the temperature and humidity resistance of the capacitive screen is significantly reduced, indicating that the selection of the material of the first transition film has a great influence on the life of the final capacitive screen.

[0160] The present invention illustrates the detailed structural features of the present invention through the above embodiments, but the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the components selected by the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A capacitive touch screen, characterized in that: The capacitive touch screen comprises a protective layer, a barrier layer, a first adhesive layer, a sensing circuit layer, a first substrate and a driving circuit layer which are arranged in sequence; The barrier layer self-protection layer comprises a second adhesive layer, a second substrate, a first transition film and a second diaphragm arranged in sequence; The transmittance of the first transition film is greater than 98%, and the material of the second diaphragm is silicon oxide.

2. The capacitive touch screen according to claim 1, characterized in that: The material of the first transition film includes resin-based organic matter and / or inorganic matter; Preferably, the resinous organic matter comprises acrylic resin and / or polyurethane resin; Preferably, the inorganic substance comprises oxides and / or nitrides; Preferably, when the first transition film is a tree lipid organic matter, the thickness of the first transition film is 4 to 10 μm; Preferably, when the first transition film is an inorganic substance, the thickness of the first transition film is 10-20 nm.

3. The capacitive touch screen according to claim 1 or 2, characterized in that: The thickness of the second diaphragm is 60 to 80 nm; Preferably, the material of the second diaphragm contains both silicon dioxide and silicon monoxide; Preferably, the content of silicon monoxide in the silicon oxide is 0.5 to 10 wt %; Preferably, the barrier layer further comprises a silicon nitride layer disposed on the second diaphragm; Preferably, the thickness of the silicon nitride layer is 10 to 20 nm; Preferably, the 24h water vapor transmission efficiency of the barrier layer is less than 10 -3 g / m 2 .

4. The capacitive touch screen according to any one of claims 1 to 3, characterized in that: The material of the second substrate includes PET or TAC; Preferably, the thickness of the second substrate is 50 to 125 μm; Preferably, the material of the second adhesive layer includes solid high-transmittance optical glue, preferably acrylic solid high-transmittance optical glue; Preferably, the thickness of the second adhesive layer is 25 to 125 μm; Preferably, the protective layer is protective glass; Preferably, the thickness of the protective layer is 1 to 3 mm; Preferably, the material of the first adhesive layer is optically transparent adhesive, preferably OCA; Preferably, the thickness of the first adhesive layer is 50 to 175 μm; Preferably, the material of the first substrate includes any one of PET, GLASS or TAC; Preferably, the thickness of the first substrate is 50-125 μm.

5. A method for preparing a capacitive touch screen according to any one of claims 1 to 4, characterized in that: The preparation method comprises the following steps: (1) The protective layer is cleaned to obtain a cleaned protective layer; (2) attaching the second adhesive layer in the barrier layer to the cleaned protective layer, and performing roller pressing and degassing treatment to composite the barrier layer and the protective layer to obtain a first intermediate screen; (2) A first adhesive layer, a sensing circuit layer, a first substrate and a driving circuit layer are sequentially arranged on the first intermediate screen to obtain the capacitive touch screen.

6. The preparation method according to claim 5, characterized in that: The cleaning in step (1) includes spray cleaning; Preferably, the spray density of the spray cleaning is 0.1-0.3 kg / cm 2 ; Preferably, the temperature of the spray cleaning is 35-40°C; Preferably, the pH of the spray cleaning liquid is 4-7.

7. The preparation method according to claim 5, characterized in that: The roller pressing pressure in step (2) is 0.3-0.6 MPa; Preferably, the temperature of the degassing treatment is 40-60°C; Preferably, the degassing treatment time is 10 to 30 minutes; Preferably, the degassing process comprises: applying pressure to degas; Preferably, the applied pressure is in the range of 0.5 to 0.7 MPa.

8. The preparation method according to claim 5, characterized in that: The preparation method of the barrier layer comprises: Disposing a first transition film on one side of the second substrate; Depositing silicon oxide on a side of the first transition film away from the second substrate to obtain a second diaphragm; A second adhesive layer is disposed on the other side of the second substrate to obtain the barrier layer.

9. The preparation method according to claim 8, characterized in that: The method of depositing silicon oxide includes magnetron sputtering or chemical vapor deposition; Preferably, the pressure range of the magnetron sputtering is ≤0.01 mbar; Preferably, the magnetron sputtering uses a high-purity silicon target with a purity of ≥99.99%; Preferably, the power of the magnetron sputtering is 18-20 kW; Preferably, the magnetron sputtering is performed in a combined atmosphere of argon and oxygen; Preferably, the ratio of the argon flow rate to the oxygen flow rate in the magnetron sputtering is 200-300 sccm:80-150 sccm.

10. An electronic device, characterized in that: The electronic device comprises the capacitive touch screen according to any one of claims 1 to 5.

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