CN212032133U

CN212032133U - Touch control screen

Info

Publication number: CN212032133U
Application number: CN202021129585.4U
Authority: CN
Inventors: 雷贝; 彭颖杰; 徐林; 王新媛; 姜锴; 潘克菲; 徐晔
Original assignee: Nuovo Film Inc; Suzhou Huige Photoelectric Technology Co ltd
Current assignee: Nuovo Film Inc; Suzhou Huige Photoelectric Technology Co ltd
Priority date: 2020-06-17
Filing date: 2020-06-17
Publication date: 2020-11-27
Anticipated expiration: 2030-06-17

Abstract

The utility model relates to a touch screen, which comprises two layers of transparent conductive electrodes bonded by an adhesive layer; the transparent conductive electrode comprises a transparent substrate and a plurality of patterned working electrodes positioned on the substrate, each working electrode consists of a nano metal wire, a nano metal rod or a nano metal film, and the working electrode positioned in the wiring area is provided with a lapping groove exposing the section of the working electrode; the insulating layer is provided with conductive channels which are correspondingly communicated with the lap joint grooves one by one; the electric connecting pieces are positioned in the overlapping grooves and the conductive channels which are in one-to-one correspondence, and the electric connecting pieces are solidified conductive slurry; and the electrode lead wire positioned on one side of the insulating layer, which is far away from the working electrode, is electrically connected with the corresponding working electrode through the electric connecting piece.

Description

Touch control screen

Technical Field

The utility model relates to a capacitive touch screen field especially relates to a touch screen.

Background

The metal nanowire conducting film is a basic material for manufacturing electronic products such as a nano silver wire large-size touch screen, a light adjustable film, a flexible touch screen and the like. The metal nanowires include but are not limited to silver nanowires.

When the patterned metal nanowire conducting film is used as an emitting layer and a receiving layer, an insulating layer is usually arranged outside the metal nanowire conducting film, and the insulating layer has the main effects of improving the structural strength of a metal nanowire layer, avoiding scratching, blocking external corrosive substances and improving the stability of a metal nanowire material. However, in the existing application, the electrical signal of the metal nanowire layer is led out from the right top of the metal nanowire conductive layer, and contact conduction is formed after silver paste printing, so that the surface conductivity of the metal nanowire needs to be emphasized, and the contact resistance of the silver paste in an area of about 1 square millimeter is required to be less than 100 ohms.

The conventional implementation methods include two methods, one is that the insulating layer is thin enough, the conductive grid formed by the metal nanowires has points exposed out of the insulating layer, and after silver paste is printed, conductive filler particles in the silver paste can be in direct contact with the metal nanowires; the other is that after silver paste is printed by silk, after a solvent in the silver paste is dissolved to destroy a surface insulating layer, conductive filler particles in the silver paste and the metal nanowires are in close contact for conduction, wherein the contact comprises direct contact and quantum tunneling type contact, namely when the distance between two conductive particles is in a nanometer level, electrons can jump between two conductors for conduction. The conduction of the two modes limits the thickness of the insulating layer on the surface of the metal nanowire, so that the metal nanowire is difficult to form real effective protection.

In view of the above, it is desirable to provide a touch panel to solve the above problems.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a can increase touch screen of insulating layer thickness.

In order to realize the purpose of the utility model, the utility model adopts the following technical scheme:

a touch screen comprises two layers of transparent conductive electrodes and an adhesive layer for bonding the two layers of transparent conductive electrodes; the transparent conductive electrode includes:

the substrate comprises a visible area and a wiring area positioned around the visible area;

the working electrodes are positioned on the substrate and are patterned, the working electrodes are composed of nano metal wires, nano metal rods or nano metal films, the working electrodes are positioned on the wiring area and structurally provided with overlapping grooves which expose the cross sections of the working electrodes, the depth of each overlapping groove is not less than two thirds of the thickness of each working electrode, or the overlapping grooves penetrate through the working electrodes along the thickness direction;

the insulating layer is positioned on one side of the working electrode, which is far away from the substrate, and conductive channels which are correspondingly communicated with the lap joint grooves one by one are arranged on the insulating layer;

the electric connecting pieces are positioned in the overlapping grooves and the conductive channels which are in one-to-one correspondence, and the electric connecting pieces are solidified conductive slurry;

the electrode lead is positioned on one side of the insulating layer, which is far away from the working electrode, and the electrode lead is electrically connected with the corresponding working electrode through the electric connecting piece;

the adhesive layer is used for bonding the substrate of one transparent conductive electrode and the insulating layer of the other transparent conductive electrode; or, the adhesive layer is adhered to the substrates of the two transparent conductive electrodes; or the adhesive layer is adhered with the insulating layers of the two transparent conductive electrodes.

A touch screen comprises a first composite board, a second composite board and an adhesive layer for adhering the first composite board and the second composite board; the first composite panel and the second composite panel each include:

the working electrodes are positioned on the substrate and are patterned, and each working electrode is composed of a nano metal wire, a nano metal rod or a nano metal film;

the insulating layer is positioned on one side of the working electrode, which is far away from the substrate;

the adhesive layer is used for bonding the substrate of the first composite board and the insulating layer of the second composite board, and the wiring area of the first composite board corresponds to the wiring area of the second composite board;

the touch screen further comprises first conductive channels in one-to-one correspondence with the working electrodes of the first composite board, second conductive channels in one-to-one correspondence with the working electrodes of the second composite board, electric connection pieces positioned in the first conductive channels and the second conductive channels, and a plurality of electrode leads positioned on one side, away from the working electrodes, of the insulating layer of the first composite board, wherein the electrode leads are electrically connected with the corresponding working electrodes through the electric connection pieces; the first conductive channel comprises a conductive channel penetrating through the insulating layer of the first composite plate and a lapping groove positioned on the working electrode of the first composite plate; the second electrically conductive passageway is including running through the auxiliary channel of first composite sheet and viscose layer, running through the electrically conductive passageway of the insulating layer of second composite sheet, be located overlap joint groove on the working electrode of second composite sheet, the degree of depth in overlap joint groove is not less than two-thirds of working electrode's thickness, perhaps overlap joint groove runs through along thickness direction working electrode.

A touch screen, comprising:

the working electrodes are respectively positioned on two sides of the substrate and are patterned, each working electrode is composed of a nano metal wire, a nano metal rod or a nano metal film, a lapping groove exposing the section of each working electrode is arranged on the structure of the working electrode positioned in the wiring area, the depth of the lapping groove is not less than two thirds of the thickness of each working electrode, or the lapping groove penetrates through the working electrodes along the thickness direction;

and the electrode lead is positioned on one side of the insulating layer, which deviates from the working electrode, and the electrode lead is electrically connected with the corresponding working electrode through the electric connecting piece.

Compared with the prior art, the beneficial effects of the utility model reside in that: the utility model discloses a touch screen, through set up the overlap joint groove on the working electrode and outwards expose working electrode's section, this section passes through electric connector and electrode lead and realizes electric contact, has changed surface electric connection's in the past mode, thereby can strengthen the thickness of insulating layer to enlarged electrode lead's application scope, even contact resistance conductive material bigger than normal behind the original silk screen printing conductive paste also can continue to use.

Drawings

Fig. 1 is a schematic structural diagram of a touch screen according to a preferred embodiment of the present invention;

fig. 2 is a schematic structural diagram of a touch screen according to another preferred embodiment of the present invention;

fig. 3 is a schematic structural diagram of a touch screen according to another preferred embodiment of the present invention;

fig. 4 is a schematic structural diagram of a touch screen according to a preferred embodiment of the present invention;

fig. 5 is a schematic structural diagram of a touch screen according to a preferred embodiment of the present invention

FIG. 6 is a schematic structural diagram of a substrate, a working electrode and an insulating layer;

FIG. 7 is a schematic illustration of the insulating layer of FIG. 6 after screen printing of a plurality of silver paste segments thereon;

FIG. 8 is a schematic view of the insulation layer of FIG. 6 after forming a plurality of breaking points and then screen printing silver paste blocks;

FIG. 9 is a schematic view of the structure of FIG. 6 after forming a conductive via and a landing slot;

FIG. 10 is a schematic illustration of the addition of conductive paste into the conductive vias and landing pads of FIG. 9;

fig. 11 is a schematic view of the transparent conductive electrode formed after routing electrode leads onto the insulating layer of fig. 10.

100-touch screen, 11-substrate, 12-working electrode, 121-lap joint groove 121, 13-insulating layer 13, 131-conductive channel, 1311-first conductive channel, 1312-second conductive channel, 14-electric connecting piece 14, 15-electrode lead 15, 2-adhesive layer, 3-silver paste block and 4-breaking point.

Detailed Description

The present application will now be described in detail with reference to specific embodiments thereof as illustrated in the accompanying drawings. These embodiments are not intended to limit the present application, and structural, methodological, or functional changes made by those skilled in the art according to these embodiments are included in the scope of the present application.

In the various illustrations of the present application, certain dimensions of structures or portions may be exaggerated relative to other structures or portions for ease of illustration and, thus, are provided to illustrate only the basic structure of the subject matter of the present application.

Referring to fig. 1 to 3, a touch panel 100 according to a preferred embodiment of the present invention includes two transparent conductive electrodes, and an adhesive layer 2 for adhering the two transparent conductive electrodes; the two layers of transparent conductive electrodes are respectively used as a driving layer and a receiving layer.

Referring to fig. 1 to 3, 6, and 9 to 11, the transparent conductive electrode includes a substrate 11, a plurality of patterned working electrodes 12 located on the substrate 11, an insulating layer 13 located on a side of the working electrodes 12 facing away from the substrate 11, and electrode leads 15 located on a side of the insulating layer 13 facing away from the working electrodes 12, where the electrode leads 15 pass through the insulating layer 13 and are connected to the working electrodes 12 in a one-to-one correspondence manner. The adhesive layer 2 is used for bonding the substrate 11 of one transparent conductive electrode and the insulating layer 13 of the other transparent conductive electrode; or, the adhesive layer 2 adheres the substrates 11 of the two transparent conductive electrodes; or, the adhesive layer 2 adheres the two insulating layers 13 of the transparent conductive electrode.

The substrate 11 may be a substrate used in a manufacturing process or other film layer coated on the substrate, and the substrate 11 is transparent and includes, but is not limited to, glass, a plastic plate, and a transparent film including, but not limited to, a PET film.

In addition, the substrate 11 includes a visible region and a routing region located around the visible region for arranging the electrode leads 15, and the visible region may also be understood as a working region, that is, the visible region is a touch region of the touch screen 100.

The thickness of the working electrode 12 is generally 30 nm-100 nm, the working electrode 12 is a patterned conductive structure formed by a nano metal wire, a nano metal rod or a nano metal film, and different working electrodes 12 are insulated, and the insulation can be realized by arranging the insulating structures at intervals or in the middle. It will be appreciated by those skilled in the art that the working electrode 12 generally covers the viewing area and that the end of the working electrode 12 is located at the routing area to facilitate electrical connection to the electrode lead 15.

The nano metal wire or the nano metal rod can be coated on the surface of the substrate 11 in the form of a solution to form a continuous conductive film layer, and preferably, the nano metal wire is a nano silver wire with the diameter of 5 nm-100 nm and the length of 15 μm-25 μm, has high conductivity and high transparency. Alternatively, the working electrode 12 is a nano metal film formed by magnetron sputtering, vacuum deposition, or the like, and has reliable conductivity.

The working electrode 12 located in the wiring region has a lap groove 121 exposing a cross section of the working electrode 12, the cross section forms at least a part of a groove wall of the lap groove 121, and the lap groove 121 is open to the substrate 11.

The cross section extends from a side of the working electrode 12 departing from the substrate 11 to a side of the substrate 11, and a projection of the cross section on a surface perpendicular to the working electrode 12 is a straight line, an arc line or other irregular lines, as long as a nano metal wire, or a nano metal rod, or a nano metal film can be exposed or protruded from the cross section into the overlapping groove 121.

Further, the depth of the lap groove 121 is not less than two thirds of the thickness of the working electrode 12 to form an effective conductive surface; preferably, the bonding groove 121 penetrates the working electrode 12 in the thickness direction, has a large cross-sectional area, and can be electrically connected to the electrode lead 15 effectively and stably.

In addition, the overlapping groove 121 may be a single groove, or the overlapping groove 121 may include several independent sub-grooves.

The bridging groove 121 is located at the middle position of the working electrode 12, is an internal groove, and is generally a closed figure, such as a circle, when viewed from the top of the transparent conductive electrode; or the overlapping groove 121 is opened at the edge of the working electrode 12, and is an edge groove, which is generally in an open pattern, such as a semicircular arc, when viewed from the top of the transparent conductive film.

The insulating layer 13 is usually a transparent resin layer, which can improve the structural strength of the working electrode 12, prevent scratches, block external corrosive substances, and improve the stability of the nano metal wire, or the nano metal rod, or the nano metal film. The sheet resistance of the insulating layer 13 on the side away from the working electrode 12 is 0.1-500 ohm/sq measured by using an eddy current sheet resistance meter, and the resistance cannot be measured by using a four-probe sheet resistance meter.

Specifically, the insulating layer 13 is an entire surface of a side of the working electrode 12 facing away from the substrate 11, or the insulating layer 13 is a patterned insulating layer 13, and only the working electrode 12 is protected.

The insulating layer 13 has a conductive channel 131 communicating with the overlapping groove 121, and preferably, the conductive channel 131 and the overlapping groove 121 are located on the same straight line, so as to facilitate synchronous formation and filling with conductive filler.

In addition, the conductive channel 131 is a channel, or the conductive channel 131 includes several independent sub-channels. Any form of the said overlapping groove 121 can communicate with any form of the conductive channel 131; preferably, when the overlapping groove 121 is a groove, the conductive channel 131 is a channel; when the overlapping groove 121 is formed by several sub-grooves, the conductive channel 131 is formed by several sub-channels, and the sub-channels correspond to the sub-grooves one to one.

In addition, the overlapping groove 121 is located in the working electrode 12, and the cross section is exposed in the working electrode 12, that is, the overlapping groove 121 is an internal groove or an internal hole; or the bridging groove 121 is located at the edge of the working electrode 121, and the cross section is exposed to the outside of the working electrode 121, that is, the cross section is an edge cross section.

Filling the conductive channel 131 and the overlapping groove 121 with a conductive paste and curing the conductive paste to form an electrical connector 14, wherein the electrical connector 14 is in direct contact with and electrically connected to the cross section of the working electrode 12 exposed in the overlapping groove 121, so as to lead out an electrical signal of the cross section of the working electrode 12 to one side of the insulating layer 13 away from the working electrode 12; the conventional surface electrical connection mode is changed, so that the thickness of the insulating layer 13 can be increased, for example, the thickness of the insulating layer 13 is not less than 10nm, preferably not less than 1 μm; and the application range of the electrode lead 15 is expanded, and even the original conductive material with larger contact resistance after silk-screen printing of the conductive paste can be continuously used.

The electrical connection 14 and the conductive mechanism of the profile include: the end part of a part of the nano metal wire or the nano metal rod extends out of the cross section into the lapping groove 121 and is electrically connected with the electric connector 14; or after the overlapping groove 121 is formed, a conductive film layer made of metal nano materials including a nano metal wire or a nano metal rod or the like or the nano metal film is turned outwards at the overlapping groove 121 to form a micron-sized conductive surface, and the micron-sized conductive surface is electrically connected with the electric connecting piece 14; or after the conductive paste is filled into the overlapping groove 121, the cross section has better side invasion, so that the electric connector 14 is electrically connected with the working electrode 12.

The conductive paste includes, but is not limited to, conductive carbon paste, conductive silver paste, and when the nano metal wire is a nano silver wire, the conductive silver paste is preferably used, and the contact resistance is low.

The electrode leads 15 are located on the insulating layer 13 at the routing area, and the electrode leads 15 are electrically connected with the corresponding working electrodes 12 through the electric connecting members 14, and each electrode lead 15 corresponds to one working electrode 12.

In a specific embodiment, the electrode lead 15 is an enameled wire, the enameled wire includes a metal wire and an insulating layer 13 covering the metal wire, and the insulation between the metal wire and the metal wire can be realized without additionally coating an insulating glue layer, so as to form an enameled wire group with a small wire pitch, and even the enameled wires can be directly overlapped together, that is, the pitch between the enameled wires can be reduced to 0, so that the width of the wire running area can be reduced. The utility model discloses in, the enameled wire includes the overlap joint portion that the metal wire outwards exposes, the overlap joint portion passes through electrical connector 14 with working electrode 12 electric connection.

In another embodiment, the electrode lead 15 is an electrode wire formed by curing conductive paste such as silver paste printed by screen printing or inkjet printing; alternatively, the electrode lead 15 is an electrode wire formed by coating a conductive film with a conductive paste such as silver paste and etching the conductive film. Also, the method reduces the requirement for silver paste, and can be used even if the contact resistance of the formed electrode lead 15 is greater than 100 ohms per square millimeter.

The utility model also provides a preparation method of touch screen for prepare any one shown touch screen 100 in fig. 1-3, including following step:

s1, forming a working electrode 12 on the substrate 11, wherein the working electrode 12 is a conductive structure composed of a nano metal wire, a nano metal rod, or a nano metal film;

s2 providing a cross section of the working electrode 12 exposed by the overlapping groove 121 in the working electrode 12 located in the wiring region of the substrate 11, wherein the overlapping groove 121 has a depth not less than two-thirds of the thickness of the working electrode 12, or the overlapping groove 121 penetrates the working electrode 12 in the thickness direction;

s3 forming an insulating layer 13 on a side of the working electrode 12 facing away from the substrate 11;

s4, forming a conductive via 131 on the insulating layer 13 in the routing area of the substrate 11;

s5, filling conductive slurry into the conductive channels 131 and the overlapping grooves 121 which are communicated in a one-to-one correspondence manner, and curing the conductive slurry to form the electric connector 14;

s6, arranging an electrode lead 15 on one side of the insulating layer 13, which is far away from the working electrode 12, wherein the electrode lead 15 is electrically connected with the corresponding working electrode 12 through the electric connector 14;

s7 bonding the two transparent conductive electrodes obtained from S1 to S6 respectively by means of an adhesive in the following manner: as shown in fig. 1, a substrate 11 of one transparent conductive electrode and an insulating layer 13 of the other transparent conductive electrode are bonded by an adhesive layer 2; alternatively, as shown in fig. 2, the insulating layer 13 of the two transparent conductive electrodes is bonded by the adhesive layer 2; or as shown in fig. 3, the substrates 11 of the two transparent conductive electrodes are bonded by the adhesive layer 2.

Wherein, S1-S6 are for descriptive convenience only and do not represent a sequence of steps; according to the different specific processes, the sequence relationship between steps S1 and S2 is: the bonding groove 121 may be formed simultaneously with the formation of the working electrode 12, or the bonding groove 121 may be formed after the formation of the working electrode 12; the sequence relationship between step S3 and step S4 is: the conductive path 131 may be formed at the same time as the insulating layer 13 is formed, or the conductive path 131 may be formed after the insulating layer 13 is formed; step S2 and step S4 may be performed separately, or may be performed simultaneously after step S3; step S5 and step S6 may be interchanged.

Moreover, in the method, the process and the sequence of the steps are mainly described, and the positions, forms, and configurations of the substrate 11, the working electrode 12, the bonding groove 121, the insulating layer 13, the conductive channel 131, the electrical connector 14, and the electrode lead 15 are the same as those described in the touch panel 100, and are not described in detail.

Specifically, step S1 includes: s11, coating a layer of conductive film on the substrate 11 by using nano materials such as nano metal wires or nano metal rods, wherein the coating process includes but is not limited to the application of high-precision slit extrusion coating equipment; s12 etching the conductive film to form a patterned electrode, wherein the etching process includes, but is not limited to, laser thin film etching, gas etching, discharge etching, chemical etching, physical etching, and mechanical etching.

Depending on the specific process, when the etching process of step S12 is the same as that of step S2 of forming the bonding groove 121, the two processes may be performed simultaneously; of course, the two steps can be carried out, and the sequence can be interchanged. After the insulating layer 13 is formed in step S3, the etching process in step S12 may be performed to form the patterned insulating layer 13 corresponding to the working electrode 12; of course, the insulating layer 13 may be formed over the entire surface in step S3 after step S12.

Or step S1 includes: the patterned working electrode 12 of the nanometal wire, or the nanometal rod, is screen printed or sprayed directly on the substrate 11 according to a predetermined pattern. Based on this method, after step S1, step S3 can form a whole insulating layer 13, or form a patterned insulating layer 13 by a mask method.

Or step S1 includes: firstly, forming a separation layer on a base material, and then forming a plurality of patterned working electrodes 12 on the separation layer; then transferring the working electrode 12 onto the substrate 11; preferably, the "forming several working electrodes 12 patterned on the substrate 11" includes: firstly, sequentially forming a separation layer and a resin layer on the substrate 11, and then forming a plurality of patterned working electrodes 12 on one side of the resin layer, which is far away from the separation layer; and then, the working electrode 12 is transferred onto the substrate 11, in this embodiment, the resin layer may also be configured as the substrate 11, and the resin layer is in direct contact with the separation layer, so as to avoid damaging the nano metal wire, the nano metal rod, or the nano metal film in the working electrode 12 during the separation process.

The nano-metal wire or rod material used in step S1 is usually a solution.

In a preferred embodiment, the nano metal wire is a nano silver wire with the diameter of 5 nm-100 nm and the length of 15 μm-25 μm, and the thickness of wet films coated by various processes is 2 μm-10 μm so as to ensure continuous and stable conductivity.

Alternatively, in step S1, a patterned nano metal film may be directly formed by a mask by magnetron sputtering or vacuum evaporation to form the working electrode 12; or a nano metal film is firstly formed on the substrate 112 by adopting a magnetron sputtering or vacuum evaporation mode, and then the patterned working electrode 12 is formed by etching.

In the present invention, the overlapping groove 121 and the conductive channel 131 may be respectively and independently formed.

Preferably, after the working electrode 12 is formed, the conductive path 131 and the overlapping groove 121 are formed at the same time; the process is briefly described, and the conductive channel 131 is connected with the lap joint groove 121 in an alignment manner, so that the subsequent filling of the conductive slurry is facilitated. Simultaneous formation here means that the same process step is used for completion.

Further, the inventor finds in research that the working electrode 12 is in the nanometer level, an inappropriate grooving process can cause the section to be non-conductive, and after many considerations and improvements, the temperature in the process of forming the overlapping groove 121 is not higher than 300 ℃, and/or the temperature in the process of forming the conductive channel 131 is not higher than 300 ℃, so as to avoid the phenomenon that the section of the working electrode 12 is not conductive due to thermal effect. Preferably, the temperature is not higher than 180 ℃, so that the nano metal wire, the nano metal rod or the nano metal film can not break, and the conductive stability is ensured.

The method for forming the conductive channel 131 and/or the overlapping groove 121 includes mechanical damage, such as scratching, scraping, drilling, cutting, grinding and vibrating, ultrasonic wave, laser etching, plasma ablation, shock wave, hole preparation and chemical etching, and the laser etching process is preferably femtosecond laser to ensure the conductivity of the section.

As shown in fig. 1 to 3, the bridging groove 121 is located in the working electrode 12, and the cross section is exposed in the working electrode 12, that is, the bridging groove 121 is an internal groove or an internal hole; or in other embodiments not shown, the overlapping groove is located at the edge of the working electrode, and the cross section is exposed to the outside of the working electrode, that is, the cross section is an edge cross section.

In step S6, the method for laying the electrode lead 15 may be any one of the prior art, or a new electrode lead 15 laying process may be designed.

For example, an enameled wire including a lap portion where the metal wire is exposed outward may be used as the electrode lead 15, and the enameled wire is laid on a side of the insulating layer 13 facing away from the working electrode 12, and the lap portion is electrically connected to the electrical connection member 14.

The electrode lead 15 can also be made of conductive paste such as silver paste, the requirement on the conductivity of the conductive paste is greatly reduced, and the arrangement method comprises but is not limited to the following steps: on the side of the insulating layer 13 facing away from the working electrode 12, a screen-printed or ink-jet printed conductive paste is cured to form an electrode lead 15. Or, coating a conductive paste on the side of the insulating layer 13 away from the working electrode 12 to form a conductive film layer, and then etching to form the electrode lead 15.

The preparation method of the touch screen further comprises the following steps: the electrode leads 15 are connected to the FPC board at the bonding regions, and a subsequent packaging step.

The above-mentioned transparent conductive electrode of the present invention and the method for manufacturing the same will be described below by way of detailed examples.

Reference example 1

Referring to fig. 6 to 8, a coating solution containing silver nanowires is coated on the surface of the transparent PET film by using a high-precision slit extrusion coating apparatus, wherein the diameter of the silver nanowires in the coating solution is about 5nm to 100nm, the length of the silver nanowires is 15 μm to 25 μm, and the solid content of the silver nanowires is 0.5%; the thickness of the coated wet film is 2 mu m-10 mu m, a metal grid layer containing nano silver wires is formed, the sheet resistance is 50ohm/sq after drying, and the visible light transmittance is not lower than 85%.

Transparent UV curing resin solution is coated by using high-precision slit extrusion coating equipment to prepare an insulating layer 13, the coating thickness is 1um, the resistance cannot be measured by using a four-probe sheet resistance instrument at the moment, and the resistance can be measured to be 50ohm/sq by using an eddy current sheet resistance instrument.

And (3) screen-printing conductive silver paste on the insulating layer 13 to form silver paste blocks 3 with the thickness of about 5 micrometers-10 micrometers and the size of 2mm x 2mm, wherein the interval between each edge of each silver paste block 3 and the adjacent silver paste block 3 is 5mm, after drying and curing, measuring the resistance between each silver paste block 3, and displaying that the circuit is broken and the silver paste blocks 3 are not conductive.

Reference example 2 differs from reference example 1 in that:

after the insulating layer 13 is formed, in a set silk-screen silver paste area, a tungsten needle is used to impact and destroy the insulating layer 13 and the metal mesh layer, so as to form a plurality of destruction points 4 with the depth of about 1 μm to 50 μm and the diameter of 0.2mm, the plurality of destruction points 4 are uniformly distributed in the overlapping area, as shown in fig. 4, 10 destruction points 4 are formed in this embodiment, and each destruction point 4 forms one sub-channel and one sub-groove on the insulating layer 13, and according to the depth of the destruction point 4, the sub-groove destroys a part of the metal mesh layer close to the insulating layer 13, or the sub-groove penetrates through the metal mesh layer.

And (3) printing conductive silver paste on the screen in the set screen printing silver paste area to form silver paste blocks 3 with the thickness of 5 mu m-10 um and the size of 1mm x 1mm, wherein the intervals between each edge of each silver paste block 3 and the adjacent silver paste block 3 are 2mm, and the silver paste is filled into the sub-channels and the sub-grooves due to the adhesion and the flowability of the silver paste.

After drying and curing, the resistance between the silver paste blocks 3 is measured, and the measured value is less than 50 ohms, which indicates that the silver paste blocks 3 are conducted with the metal grid layer formed by the nano silver wires.

As can be seen from comparison between reference examples 1 and 2, when the bridging groove 121 is formed in the nano silver wire conductive film, the cross section of the nano silver wire conductive film has conductive performance, and the silver paste flowing into the bridging groove 121 and the cross section of the metal mesh layer can be effectively electrically connected.

Example 1A

The preparation method of the touch screen comprises the following steps:

1) coating a coating liquid containing a nano silver wire on the first surface of the transparent PET film by using high-precision slit extrusion coating equipment, wherein the diameter of the nano silver wire in the coating liquid is about 18nm, the length of the nano silver wire is 15-25 mu m, and the solid content of the nano silver wire is 0.5%; the thickness of the coated wet film is 2 mu m-10 mu m, a metal grid layer of the nano silver wires is formed, the sheet resistance is 50ohm/sq after drying, and the visible light transmittance is not lower than 85%;

2) coating a transparent UV curing resin solution on the metal grid layer by using high-precision slit extrusion coating equipment to prepare an insulating layer 13, wherein the thickness of the coating is 1um, the resistance cannot be measured by a four-probe sheet resistance instrument at the moment, and the resistance can be measured to be 50ohm/sq by using an eddy current sheet resistance instrument;

3) loading a tungsten needle on a triaxial mechanical platform, and impacting and damaging the insulating layer 13 and the metal grid layer in a set lap joint area of 1mm x 1.5mm to form a plurality of damage points with the depth of about 1 mu m-50 um and the diameter of 0.2mm, wherein the damage points form the conductive channel 131 and the lap joint groove 121 which are correspondingly communicated;

4) screen-printing an electrode lead 15 silver paste layer with the thickness of about 5-10 mu m in the wiring area, and drying and curing; silver paste is filled into the conductive channel 131 and the overlapping groove 121 due to the adhesiveness and fluidity of the silver paste;

5) performing thin film laser etching on the conductive thin film printed with the silver paste to form a patterned working electrode 12 and a corresponding electrode lead 15, and respectively manufacturing a TX circuit and an RX circuit;

6) attaching an RX circuit and a TX circuit by using OCA optical cement; the attaching mode is as follows: a substrate 11 of one transparent conductive electrode and an insulating layer 13 of the other transparent conductive electrode are bonded through OCA optical cement; or, the substrate 11 of two transparent conductive electrodes is bonded through the OCA optical cement; alternatively, the insulating layers 13 of the two transparent conductive electrodes are bonded by OCA optical cement.

7) And binding an FPC (flexible printed circuit) board at the tail end of the electrode lead 15, cutting the whole appearance, and attaching a cover plate to obtain the capacitive screen touch panel.

Example 1B

Step 1), 2) are the same as step 1), 2) of example 1A;

3) performing thin-film laser etching on the conductive film obtained in the step 2) to form a patterned conductive circuit, namely a working electrode 12;

4) bonding the two films obtained in step 3 by using an optically transparent adhesive to form an acceptance layer RX and an emission layer TX, respectively; the attaching scheme comprises opposite attaching and same-direction attaching;

5) drilling a hole in the set lap joint area until the position of the working electrode 12 to form a conductive section;

6) and pouring silver paste into the holes to form lap joint points, and then, silk-screening the silver paste to manufacture the electrode leads 15, so as to obtain the touch screen 100.

Example 1C:

step 1), 2) are the same as step 1), 2) of example 1A;

3) performing film laser etching on the two conductive films obtained in the step 2) on roll-to-roll laser film etching equipment to respectively form patterned conductive circuits, namely an Rx receiving layer circuit and a TX transmitting layer circuit;

4) performing roll-to-roll alignment compounding, and attaching an Rx receiving layer circuit and a TX transmitting layer circuit; the attaching scheme comprises opposite attaching, same-direction attaching and back attaching;

5) cutting the double-layer transparent conductive circuit film with the required size according to the size requirement of the touch screen 100 to be manufactured;

6) drilling holes in the designed lap joint area until the position of the working electrode 12 is reached to form a conductive section;

7) and pouring silver paste into the holes to form lap joints, compounding electrode leads 15 made of enameled wires, and conducting by using conductive silver paste to obtain the nano silver wire capacitive touch screen 100.

EXAMPLE 1D transfer film

1) Coating a separation layer with the dry film thickness of 100nm, a resin layer with the dry film thickness of 1um, a nano-silver wire layer with the dry film thickness of 100nm and an insulating layer 13 with the dry film thickness of 1um on the surface of the PET film in sequence, and measuring the resistance to be 50ohm/sq by using an eddy current sheet resistance meter;

2) performing thin film laser etching on the conductive film obtained in the step 1) to form a patterned conductive circuit; simultaneously, manufacturing a nano-silver wire conductive profile in a wire lapping area of a preformed RX layer and a preformed TX layer in the wire area through drilling;

3) compounding a resin layer, a nano silver wire layer and an insulating layer 13 on the surface of a transferred substrate 11 through an optical transparent adhesive layer, wherein the surface is cover glass;

4) repeating the step 3 to form a double-layer structure; at the moment, the RX hole position reserved by the TX film is just vacated; silver paste is filled in to form lap joint electrode points.

5) And manufacturing an electrode lead 15 in the wiring area, and conducting with the lapping electrode point, so as to finish the ultra-thin touch screen 100.

Example 1E:

step 1: repeating the steps 1) and 2) in the embodiment 1D to form RX and TX circuits with conductive sections, and printing silver paste to form electrode leads 15 which are connected with the working electrodes 12 in a one-to-one correspondence manner;

step 2: sequentially transferring RX and TX to the surface of cover glass by using OCA glue; and obtaining the capacitive touch screen.

Example 1E

Step 1: repeating the step 1 of the example 1C to obtain a transparent conductive film capable of being subjected to pattern transfer;

step 2: forming a patterned UV glue layer on the surface of a base material (PET) by using an ink-jet printing device;

and step 3: and (3) compounding the conductive film obtained in the step (1), and curing the glue layer. And lifting the transparent conductive film which can be subjected to pattern transfer to form the nano silver wire transparent conductive circuit on the surface of the substrate. The same steps complete the TX line, RX line;

and 4, step 4: and screen printing silver paste as a frame lead, and forming section conduction by the silver paste, the TX circuit and the RX circuit to obtain the capacitive touch screen.

As shown in fig. 4, 6, and 9 to 11, a touch panel 100 according to another embodiment of the present invention includes a substrate 11, a plurality of patterned working electrodes 12 respectively located on two sides of the substrate 11, an insulating layer 13 located on one side of each of the working electrodes 12 away from the substrate 11, and an electrode lead 15 located on one side of the insulating layer 13 away from the working electrodes 12, where the electrode lead 15 passes through the insulating layer 13 and is connected to the working electrodes 12 in a one-to-one correspondence manner.

This embodiment differs from the embodiment shown in fig. 1 to 3 only in that: the two working electrodes 12 of the present invention are respectively located at two sides of the substrate 11; it can also be understood that two transparent conductive electrodes share the same substrate 11 without being bonded by the adhesive layer 2. Other structures and arrangement thereof refer to the embodiments shown in fig. 1 to 3, and are not described herein again.

The utility model also provides a preparation method of touch screen for prepare the touch screen 100 shown in FIG. 4, specifically include the following steps:

s1 forming working electrodes 12 on two sides of the substrate 11, respectively, the working electrodes 12 being conductive structures composed of nano metal wires, nano metal rods, or nano metal films;

s6, an electrode lead 15 is disposed on a side of the insulating layer 13 facing away from the working electrode 12, and the electrode lead 15 is electrically connected to the corresponding working electrode 12 via the electrical connector 14.

The preparation method of the touch screen is only different from the preparation method of the touch screen in that: the working electrodes 12 are formed on two sides of the substrate 11, that is, two transparent conductive electrodes are prepared on two sides of the substrate 11, so that the two transparent conductive electrodes do not need to be bonded by the adhesive layer 2.

The structure of the touch screen 100 and the manufacturing method thereof will be described in detail through specific embodiments.

Example 2A

3) repeating the steps 1) and 2), and sequentially preparing a metal grid layer and an insulating layer 13 on the second surface of the transparent PET film; namely, two sides of the transparent substrate are respectively coated to form a double-sided conductive film;

4) adopting roll-to-roll double-sided film laser etching to form a universal patterned conductive path which is respectively an RX circuit and a TX circuit;

5) cutting into required shape according to requirement;

6) loading a tungsten needle on a triaxial mechanical platform, impacting and damaging the insulating layer 13 and the metal grid layer in a set lap joint area of 1mm x 1.5mm to form a plurality of damage points with the depth of about 1 mu m-50 um and the diameter of 0.2mm, wherein the damage points form the correspondingly communicated conductive channel 131 and lap joint groove 121, and the silver paste with low viscosity at the lap joint area is filled into the conductive channel 131 and the lap joint groove 121 due to the adhesiveness and the fluidity of the silver paste and is solidified to form an electric connecting piece 14;

7) screen-printing an electrode lead 15 silver paste layer with the thickness of about 5-10 mu m in the wiring area, and drying and curing; the silver paste layer was laser etched to form individual electrode leads 15,

8) and binding an FPC (flexible printed circuit) board at the tail end of the electrode lead 15, cutting the whole appearance, and attaching a cover plate to obtain the capacitive screen touch panel.

Example 2B: back-to-back film

Steps 1), 2), 3) are the same as steps 1), 2), 3) of example a, respectively;

4) adopting a roll-to-roll double-sided etching process, such as a gas etching process, printing barrier layers on the two sides of the film in the step 3), and forming general patterned conductive paths, namely an RX circuit and a TX circuit, through gas etching;

5) cutting into required shape according to requirement;

Referring to fig. 5, 6, and 9 to 11, a touch panel 100 according to another embodiment of the present invention includes a first composite board, a second composite board, and an adhesive layer 2 for bonding the first composite board and the second composite board; the first composite board and the second composite board both comprise a transparent substrate 11, a plurality of patterned working electrodes 12 positioned on the substrate 11, and an insulating layer 13 positioned on one side of the working electrodes 12 departing from the substrate 11, wherein the substrate 11 comprises a visible area and a wiring area positioned around the visible area; the working electrode 12 is composed of a nano metal wire, a nano metal rod or a nano metal film; the viscose layer 2 is used for bonding the substrate 11 of the first composite board and the insulating layer 13 of the second composite board, and the wiring area of the first composite board corresponds to the wiring area of the second composite board.

The touch screen 100 further comprises first conductive channels 1311 corresponding to the working electrodes 12 of the first composite board one by one, second conductive channels 1312 corresponding to the working electrodes 12 of the second composite board one by one, electrical connection members 14 located in the first conductive channels 1311 and the second conductive channels 1312, and a plurality of electrode leads 15 located on one side, away from the working electrodes 12, of the insulating layer 13 of the first composite board, wherein the electrode leads 15 are electrically connected with the corresponding working electrodes 12 through the electrical connection members 14; the first conductive channel 1311 includes a conductive channel 131 penetrating the insulating layer 13 of the first composite plate, a lap groove 121 on the working electrode 12 of the first composite plate; the second conductive channel 1312 includes an auxiliary channel penetrating the first composite plate and the adhesive layer 2, a conductive channel 131 penetrating the insulating layer 13 of the second composite plate, and a lap joint groove 121 on the working electrode 12 of the second composite plate.

As can be seen from comparison between this embodiment and the touch panel 100 shown in fig. 1, the transparent conductive electrode formed by the first composite plate is the same as the transparent conductive electrode located above in fig. 1; the transparent conductive electrode formed by the second composite plate part is different from the transparent conductive electrode positioned below in fig. 1 in that: the working electrodes 12 on the second composite plate are connected to the electrode leads 15 on the first composite plate through the second conductive paths 1312 in a one-to-one correspondence, and other structures will not be described.

In a preferred embodiment, the auxiliary channel has a larger aperture than the conductive channel 131 extending through the insulating layer 13 of the second composite plate, so as to prevent the conductive paste from flowing inefficiently and filling the conductive channel 131.

The utility model also provides a preparation method of the touch screen, so as to prepare the touch screen 100 shown in figure 5; the preparation method of the touch screen comprises the following steps:

s1 forming a plurality of patterned working electrodes 12 on the substrate 11, wherein the working electrodes 12 are formed by nano metal wires, nano metal rods, or nano metal films;

s2 forming an insulating layer 13 on a side of the working electrode 12 facing away from the substrate 11;

s3 repeating the steps S1-S2 to obtain a first composite board and a second composite board;

s4, the first composite board and the second composite board are bonded through viscose glue, and the bonding mode is as follows: the substrate 11 of the first composite board and the insulating layer 13 of the second composite board are bonded through the adhesive layer 2, and the wiring area of the substrate 11 of the first composite board corresponds to the wiring area of the substrate 11 of the second composite board;

s5, forming a first conductive channel 1311 corresponding to the working electrode 12 of the first composite board and an auxiliary channel corresponding to the working electrode 12 of the second composite board on the insulating layer 13 in the routing area of the first composite board; the first conductive channel 1311 includes a conductive channel 131 penetrating through the insulating layer 13 of the first composite plate, and a lap groove 121 on the working electrode 12 of the first composite plate, a depth of the lap groove 121 is not less than two thirds of a thickness of the working electrode 12, or the lap groove 121 penetrates through the working electrode 12 in a thickness direction;

s6 forming a conductive channel 131 penetrating through the insulating layer 13 of the second composite board and a bridging groove 121 located on the working electrode 12 of the second composite board on the insulating layer 13 in the routing area of the second composite board, wherein the depth of the bridging groove 121 is not less than two thirds of the thickness of the working electrode 12, or the bridging groove 121 penetrates through the working electrode 12 along the thickness direction;

s7, filling conductive paste into the first conductive channel 1311, the auxiliary channel, the conductive channel 131 on the second composite board, and the lap joint groove 121, and curing the conductive paste to form the electrical connector 14;

s8, a plurality of electrode leads 15 are disposed on the side of the insulating layer 13 of the first composite board facing away from the working electrode 12, and the electrode leads 15 are electrically connected to the corresponding working electrode 12 through the electrical connectors 14.

Wherein, S1-S8 are for descriptive convenience only and do not represent a sequence of steps; specifically, the sequence of steps S1-S3 is relatively fixed; the step S4 may be located after any of the steps S5 to S8; according to the different specific processes, the sequence relationship among the steps S1, S5 and S6 is as follows: the lap groove 121 may be formed simultaneously with or after the working electrode 12 is formed; the sequence relationship between step S2 and steps S5 and S6 is: the conductive path 131 may be formed simultaneously with or after the formation of the insulating layer 13; and the lap joint groove 121 and the corresponding conductive path 131 may be implemented separately or synchronously after step S2.

In one embodiment, a method for manufacturing a touch screen includes: s1 forming a plurality of patterned working electrodes 12 on the substrate 11, wherein the working electrodes 12 are formed by nano metal wires, nano metal rods, or nano metal films; s2 forming an insulating layer 13 on a side of the working electrode 12 facing away from the substrate 11; s3 bonding the first composite sheet and the second composite sheet obtained in S1 to S2 by adhesives in the following manner: the substrate 11 of the first composite board and the insulating layer 13 of the second composite board are bonded through the adhesive layer 2, and the wiring area of the substrate 11 of the first composite board corresponds to the wiring area of the substrate 11 of the second composite board; after S4 bonding, arranging a first conductive channel 1311 corresponding to the working electrode 12 of the first composite board and a second conductive channel 1312 corresponding to the working electrode 12 of the second composite board on the insulating layer 13 in the wiring area of the first composite board, wherein the first conductive channel 1311 comprises a conductive channel 131 penetrating through the insulating layer 13 of the first composite board and a lap joint groove 121 positioned on the working electrode 12 of the first composite board; the second conductive channel 1312 includes an auxiliary channel penetrating through the first composite plate and the adhesive layer 2, a conductive channel 131 penetrating through the insulating layer 13 of the second composite plate, and a lap joint groove 121 on the working electrode 12 of the second composite plate; s5, filling the first conductive channel 1311 and the second conductive channel 1312 with conductive paste, and curing the conductive paste to form an electrical connector 14; s6, a plurality of electrode leads 15 are disposed on the side of the insulating layer 13 of the first composite board facing away from the working electrode 12, and the electrode leads 15 are electrically connected to the corresponding working electrode 12 through the electrical connectors 14.

Alternatively, in other embodiments, the first conductive vias 1311 and the second conductive vias 1312 are formed on the first composite board and the second composite board, and then bonded to each other.

To sum up, the utility model discloses a transparent conductive electrode 100, through set up the section that overlap joint groove 121 outwards exposes working electrode 12 on conductive electrode 2, this section passes through electric connector 14 and electrode lead 15 and realizes electric contact, has changed surperficial electric connection's in the past mode, thereby can strengthen insulating layer 13's thickness to enlarged electrode lead 15's application scope, even contact resistance is bigger than normal conducting material also can continue to use behind the conductive paste of original silk screen printing.

It should be understood that although the present description refers to embodiments, not every embodiment contains only a single technical solution, and such description is for clarity only, and those skilled in the art should make the description as a whole, and the technical solutions in the embodiments can also be combined appropriately to form other embodiments understood by those skilled in the art.

The above list of details is only for the feasible embodiments of the present invention, and is not intended to limit the scope of the present invention, and all equivalent embodiments or modifications that do not depart from the technical spirit of the present invention are intended to be included within the scope of the present invention.

Claims

1. A touch screen comprises two layers of transparent conductive electrodes and an adhesive layer for bonding the two layers of transparent conductive electrodes; characterized in that the transparent conductive electrode comprises:

2. A touch screen, comprising:

3. A touch screen is characterized by comprising a first composite board, a second composite board and an adhesive layer for bonding the first composite board and the second composite board; the first composite panel and the second composite panel each include:

4. The touch screen of any one of claims 1 to 3, wherein the nano metal wires are nano silver wires with a diameter of 5nm to 100nm and a length of 15 μm to 25 μm.

5. The touch screen of any one of claims 1-3, wherein the insulating layer has a thickness of no less than 10 nm.

6. The touch screen of any one of claims 1 to 3, wherein the overlapping groove is a groove, or the overlapping groove comprises several independent sub-grooves;

and/or the conductive channel is a channel or the conductive channel comprises several independent sub-channels.

7. The touch screen of any one of claims 1 to 3, wherein the electrode lead is an enameled wire, and the enameled wire comprises a lap joint part where a metal wire is exposed outwards;

or, the electrode lead is an electrode wire formed by screen printing or ink-jet printing of conductive paste solidification;

or the electrode lead is an electrode wire formed by coating conductive paste such as silver paste into a conductive film and then etching the conductive film.