CN111667940A

CN111667940A - Ultrathin composite transparent conductive film and preparation method thereof

Info

Publication number: CN111667940A
Application number: CN201910174710.9A
Authority: CN
Inventors: 周小红; 基亮亮; 姚益明; 陈林森
Original assignee: Ivtouch Co ltd
Current assignee: Ivtouch Co ltd
Priority date: 2019-03-08
Filing date: 2019-03-08
Publication date: 2020-09-15

Abstract

The invention discloses an ultrathin composite transparent conductive film which comprises a transparent substrate, wherein a first UV adhesive layer, a second UV adhesive layer and a third UV adhesive layer are arranged on one surface of the transparent substrate; the first UV adhesive layer is subjected to patterned imprinting, curing and conductive material filling to form a grid-shaped groove of the first conductive layer and a lead groove of the first lead area, and the depth of the grid-shaped groove of the first conductive layer and the depth of the lead groove of the first lead area are smaller than the thickness of the first UV adhesive layer; a second UV adhesive layer is arranged on the surface of the first UV adhesive layer and serves as a reinforced insulating supporting layer; the third UV adhesive layer is subjected to patterned imprinting, curing and conductive material filling to form a grid-shaped groove of the second conductive layer and a lead groove of the second lead area, and the depth of the grid-shaped groove of the second conductive layer and the depth of the lead groove of the second lead area are not larger than the thickness of the third UV adhesive layer. The conductive film has the advantages of simple structure, simplified process, stable process and wide application scene.

Description

Ultrathin composite transparent conductive film and preparation method thereof

Technical Field

The invention relates to the technical field of conductive films, in particular to an ultrathin composite transparent conductive film, a preparation method thereof and a product using the conductive film.

Background

The transparent conductive film is a thin film with good conductivity and high light transmittance in a visible light wave band, is widely applied to the fields of flat panel display, photovoltaic devices, touch panels, electromagnetic shielding and the like, and has wide market space. Due to various defects of ITO, flexible, low-resistance metal mesh-type transparent conductive films are playing an increasingly important role.

A transparent conductive film in the prior art refers to "a film capable of conducting electricity and realizing some specific electronic functions", and generally a conductive layer is manufactured on a transparent substrate, which generally includes a transparent substrate layer and a related metal buried layer; the surface of the transparent substrate layer is provided with a patterned and communicated groove network, and the groove network is filled with a conductive material to form a conductive film.

The existing transparent conductive film is formed with a single conductive layer on the surface of a substrate, and the conductive structure only has the conductive function of a general conductive film and does not have the circuit function of a special sensor. For example, when the touch sensor is applied to a mutual capacitance type capacitive touch sensor having upper and lower electrodes, a post-process such as adding a lead region is required, and a touch sensor is formed by combining two circuit films processed in the post-process with an optical adhesive.

In the transparent conductive film manufacturing method in the prior art, a micro-processing technology such as photoetching is adopted to manufacture a micro-structure, a groove is formed by an embossing technology, and conductive ink is filled in the groove and sintered. The single transparent conductive film manufactured in the manufacturing step does not consider the material deformation caused by the process, so that the problem of size deformation of the capacitance electrode pattern is solved. In the actual production of mass products, the problems of low yield, high cost and the like exist.

The conductive film produced by the prior art generally has the following technical problems that the production process is complex, the product quality cannot be stably controlled, the yield is low, and particularly, the thickness of the product of the conventional capacitive screen is limited by basically adopting a process of mutually laminating two transparent conductive films, so that the conventional capacitive screen does not meet the trend of ultra-light and ultra-thin development of the conventional touch screen and has high cost; in the future, electronic equipment gradually develops towards curved surface design and flexible screen design, but a touch module made of two transparent conductive films which are attached to each other is poor in bending resistance.

Therefore, the invention provides a functional transparent conductive film with a multilayer composite structure and a manufacturing method thereof, and overcomes the defects of the existing product structure and the manufacturing method.

Disclosure of Invention

The invention aims to overcome the defects in the prior art, solve the problems in the prior art and provide the ultrathin composite transparent conductive film which is simple in structure, simplified in process, stable in process, low in cost and wide in application scene.

In order to solve the technical problems, the invention provides the following technical scheme: an ultrathin composite transparent conductive film comprising a transparent substrate:

a first UV adhesive layer, a second UV adhesive layer and a third UV adhesive layer are arranged on one surface of the transparent substrate;

the first UV adhesive layer is a first UV curing adhesive layer coated on the surface of the transparent substrate, the first UV adhesive layer is subjected to patterned imprinting and curing to form a grid-shaped groove of the first conductive layer and a lead groove of the first lead area, the grid-shaped groove of the first conductive layer and the lead groove of the first lead area are filled with conductive materials, and the depth of the grid-shaped groove of the first conductive layer and the depth of the lead groove of the first lead area are smaller than the thickness of the first UV adhesive layer;

a second UV adhesive layer is arranged on the surface of the first UV adhesive layer and serves as a reinforced insulating supporting layer;

the surface of the second UV adhesive layer is provided with a third UV adhesive layer, the surface of the third UV adhesive layer is subjected to patterned imprinting and curing to form latticed grooves of the second conducting layer and lead grooves of the second lead area, the latticed grooves of the second conducting layer and the lead grooves of the second lead area are filled with a conductive material, and the depth of the latticed grooves of the second conducting layer and the depth of the lead grooves of the second lead area are not larger than the thickness of the third UV adhesive layer.

As a preferred scheme of the ultrathin composite transparent conductive film, the invention comprises the following steps: the first UV adhesive layer is subjected to patterned imprinting and curing to form a grid-shaped groove of the first conducting layer, a lead groove of the first lead area and an alignment pattern groove of the first alignment mark, the grid-shaped groove of the first conducting layer, the lead groove of the first lead area and the alignment pattern groove of the first alignment mark are filled with a conducting material, and the grid-shaped groove of the first conducting layer, the lead groove of the first lead area and the alignment pattern groove of the first alignment mark are all deeper than the first UV adhesive layer;

the surface of the third UV adhesive layer is subjected to patterned imprinting and curing to form a latticed groove of the second conducting layer, a lead groove of the second lead area and a counterpoint pattern groove of the second counterpoint mark, the latticed groove of the second conducting layer, the lead groove of the second lead area and the counterpoint pattern groove of the second counterpoint mark are filled with conductive materials, and the depths of the latticed groove of the second conducting layer, the lead groove of the second lead area and the counterpoint pattern groove of the second counterpoint mark are not more than the thickness of the third UV adhesive layer;

the patterns of the first alignment mark and the second alignment mark are either reserved or cut in the transparent conductive film product.

As a preferred scheme of the ultrathin composite transparent conductive film, the invention comprises the following steps: the thickness of the second UV adhesive layer is 1-10 microns.

As a preferred scheme of the ultrathin composite transparent conductive film, the invention comprises the following steps: the second UV adhesive layer and the third UV adhesive layer are made of different materials, and the first UV adhesive layer and the third UV adhesive layer are made of the same or different materials.

As a preferred scheme of the ultrathin composite transparent conductive film, the invention comprises the following steps: the electric connection region of the first lead region is not coated with a second layer of UV curing adhesive, and the electric connection region of the second lead region of the third UV adhesive layer is not overlapped with the electric connection region of the first lead region of the first UV adhesive layer.

As a preferred scheme of the ultrathin composite transparent conductive film, the invention comprises the following steps: an adhesion promoting layer is coated between the transparent substrate and the first UV adhesive layer or adhesion promoting treatment is carried out;

and/or an adhesion promotion layer is coated between the first UV adhesive layer and the second UV adhesive layer or adhesion promotion treatment is carried out;

and/or an adhesion promoting layer is coated between the second UV adhesive layer and the third UV adhesive layer or adhesion promoting treatment is carried out.

As a preferred scheme of the ultrathin composite transparent conductive film, the invention comprises the following steps: the second UV adhesive layer is a composite layer formed by coating UV curing adhesive on the surface of the first UV adhesive layer for multiple times, and the surface of the electric connection area of the first lead area is not covered with the second UV adhesive layer.

As a preferred scheme of the ultrathin composite transparent conductive film, the invention comprises the following steps: the latticed grooves of the first conducting layer and the second conducting layer and the lead grooves of the first lead area and the second lead area are filled with nano silver paste, nano copper paste, graphene materials, nano silver wires or carbon nanotube materials.

As a preferred scheme of the ultrathin composite transparent conductive film, the invention comprises the following steps: the upper surface of third UV glue film is provided with the protective layer, the protective layer is polymer layer, and first UV glue film, second UV glue film, third UV glue film, protective layer and transparent basement form compound transparent conducting film together, the electric connection district of the second lead wire district on third UV glue film does not coincide with the electric connection district of the first lead wire district on first UV glue film.

A preparation method of an ultrathin composite transparent conductive film is characterized by comprising the following main steps:

the method comprises the following steps: coating a first layer of UV curing adhesive on the surface of the transparent substrate, and carrying out patterned imprinting and curing on the first layer of UV curing adhesive to form a latticed groove of the first conducting layer, a lead groove of the first lead area and a patterned groove of the first alignment mark, so that the depth of the latticed groove and the lead groove is smaller than the thickness of the first UV adhesive layer;

step two: filling conductive materials into the latticed grooves of the first conductive layer, the lead grooves of the first lead area and the graphic grooves of the first alignment marks to form a first UV adhesive layer;

step three: then selectively coating a second layer of UV curing adhesive on the surface of the first UV adhesive layer to form a second UV adhesive layer, wherein the second layer of UV curing adhesive is not coated on the electric connection region of the first lead region;

step four: coating a third layer of UV curing adhesive on the surface of the second UV adhesive layer, carrying out graphical alignment imprinting and curing on the third layer of UV curing adhesive to form a latticed groove with a second conductive layer, a lead groove of a second lead area and a graphical groove with a second alignment mark, wherein the depth of the latticed groove of the second conductive layer and the depth of the lead groove of the second lead area are not more than the thickness of the third UV adhesive layer, and an electric connection area of the second lead area is not overlapped with an electric connection area of the first lead area;

step five: and filling the grid-shaped groove of the second conducting layer, the lead groove of the second lead area and the graphic groove of the second alignment mark with a conducting material.

A structure of an ultrathin composite transparent conductive film comprises a transparent substrate, wherein a first UV adhesive layer, a second UV adhesive layer and a third UV adhesive layer are arranged on one surface of the transparent substrate;

the first UV adhesive layer is a first UV curing adhesive layer coated on the surface of the transparent substrate, the first UV curing adhesive layer is subjected to graphical imprinting and is cured to form latticed grooves of the first conducting layer, the latticed grooves of the first conducting layer are filled with conducting materials, and the depth of the latticed grooves is smaller than the thickness of the first UV adhesive layer;

the second UV adhesive layer is a second UV curing adhesive layer arranged on the surface of the first UV adhesive layer and is cured to form a second UV adhesive layer serving as a reinforced insulating support layer;

the third UV glue layer is a third UV curing glue layer arranged on the surface of the second UV glue layer, the third UV curing glue layer is subjected to patterned imprinting and curing to form latticed grooves with a second conducting layer, the latticed grooves of the second conducting layer are filled with conducting materials, and the depth of the latticed grooves is not larger than the thickness of the third UV glue layer.

A touch display panel comprising a display device, further comprising the ultrathin composite transparent conductive film of any one of claims 1 to 9.

A large-size touch control all-in-one machine device comprises a display device, a CPU (Central processing Unit) and a power supply, wherein the display device comprises a touch control panel, and the touch control panel comprises the ultrathin composite transparent conductive film.

A composite transparent conductive film comprising a transparent substrate: one surface of the transparent substrate is subjected to patterned imprinting and forms a grid-shaped groove of the first conducting layer and a lead groove of the first lead area, and the grid-shaped groove of the first conducting layer and the lead groove of the first lead area are filled with conducting materials;

a second UV adhesive layer is arranged on one surface of the transparent substrate, which is provided with the first conductive layer, and serves as a reinforced insulating supporting layer, and a second UV adhesive layer is not coated on the electric connection region of the first lead region;

the surface of the second UV adhesive layer is provided with a third UV adhesive layer, the surface of the third UV adhesive layer is subjected to graphical imprinting and curing to form a latticed groove of the second conductive layer and a lead groove of the second lead area, the latticed groove of the second conductive layer and the lead groove of the second lead area are filled with conductive materials, and the depth of the latticed groove of the second conductive layer and the depth of the lead groove of the second lead area are not more than the thickness of the third UV adhesive layer; the electrical connection region of the second lead pad does not overlap the electrical connection region of the first lead pad.

The applicant of the patent is engaged in pressing grooves for embedding conductive metal particles and grids for light transmission on a transparent substrate by utilizing a nano-imprinting technology for a long time, and obtains the transparent conductive film with high light transmission rate and good conductivity by designing the line width and the depth of the grooves and the proportion of the grooves in the whole transparent conductive film. Based on the prior technical accumulation, the inventor tries a plurality of schemes before finding the technical scheme of the patent, but all the schemes have poor effect.

Although the technical scheme is better in theory, two or more patterned transparent conductive films can be insulated from each other by only controlling the thickness of the upper transparent adhesive layer to be greater than the depth of the upper conductive layer, in fact, the inventors have conducted a lot of experiments, and found that the technical scheme is too low in yield and not feasible for mass production, and please refer to experimental data and analysis in the specific embodiment section in detail.

The inventor can obtain the technical scheme of the patent after a plurality of improvements and continuous attempts, and the technical scheme of the patent at least has the following beneficial technical effects:

1. according to the ultrathin composite transparent conductive film, the first conductive layer and the second conductive layer are isolated by the aid of the independently arranged reinforcing insulation supporting layer creatively, the second conductive layer is arranged in the third UV adhesive layer, and the third UV adhesive layer is arranged on the second UV adhesive layer (serving as the reinforcing insulation supporting layer) which is stamped or coated and solidified, so that the insulation effect between the first conductive layer and the second conductive layer can be greatly improved, and the problem of short circuit of the conductive layers is effectively solved.

According to the research and development reference example of fig. 2 of the present invention, it is found that the yield is very low and a large number of conductive layer short circuits are present in the structure in which the double-layered patterned transparent conductive film is directly disposed on the transparent substrate, and the problems may be caused by various factors such as high temperature processing cracks, solvent volatilization, defects formed in the polymer, and the like. The deep reason is that the processing treatment of the polymer material related to the product and the process is a technology across subjects, and the processing treatment of the polymer material relates to the intersection of multiple subjects such as polymer chemistry, chemical engineering, polymer physics, engineering thermophysics, process control and the like. The properties of the polymer material are usually closely related to the chemical structure of the polymer material, which can be controlled by the processing technology of the polymer material, so many processing technologies that seem to be slightly changed often have unexpected changes on the control of the output quality of the polymer material.

The aforesaid problem can effectively be solved to the second UV glue film that this patent set up alone, has produced better technological effect. For example, in the research and development reference example shown in fig. 2 of the present invention, the second conductive layer is directly disposed on the first conductive layer of the first UV glue layer, and due to penetration of the conductive material caused by various factors in the processing of the polymer material, short circuit is easily caused, and the yield is too low to be practically produced.

This patent sets up solitary enhancement insulating support layer, play certain effect of smoothing, then impression third UV glue film on the second UV glue film after the solidification, when third UV glue film surface pattern impression and filling conducting material preparation second conducting layer, because except keeping apart between first conducting layer and the second conducting layer having the third UV glue film, still keep apart the second UV glue film that has solidified, consequently the problem of the interlaminar short circuit of two-layer conducting layer hardly appears, thereby improve the yield of product greatly.

And according to experimental data, the technical effect that the thickness of the third UV glue layer is obviously improved by arranging the independent reinforced insulating support layer is obviously effective.

Simultaneously, the technical scheme of this patent also can be under the original thickness of control conducting film product is unchangeable or thinner prerequisite, suitably be thin with first UV glue film and third UV glue film, reserve the second UV glue film that the thickness space set up alone and carry out insulating isolation, whole electronic product has just so thinner.

2. The reinforced insulation supporting layer added in the patent plays a role in reinforcing insulation on one hand, and meanwhile, the layer structure and the upper and lower two layers of conductive layers form a composite layer structure, so that the bending resistance of the conductive film is improved, the stability of a product is further improved, the application scene of the product is enlarged, and the flexible screen is suitable for multi-point touch requirements.

3. The invention also provides a preparation method for producing the ultrathin composite transparent conductive film, which can be used for preparing the ultrathin composite transparent conductive film in a large scale, simplifies the preparation process, improves the yield, improves the production efficiency of products and reduces the product cost.

Drawings

The invention is further described with reference to the following figures and examples:

fig. 1 is a schematic perspective view of an ultrathin composite transparent conductive film according to a first embodiment of the present invention;

fig. 2 is a schematic view of the structure of a transparent conductive film of the reference example developed by the inventors;

FIG. 3 is a schematic cross-sectional view of an ultrathin composite transparent conductive film according to a first embodiment of the present invention;

fig. 4 is a schematic structural view of an ultrathin composite transparent conductive film according to a second embodiment of the present invention;

FIG. 5 is a graph of the thickness of the second UV glue layer and the yield rate;

FIG. 6 is a graph of the thickness and yield of a third UV adhesive layer without a second UV adhesive layer;

FIG. 7 is a schematic view of an electrical connection region of a first conductive layer lead pad and an electrical connection region of a second conductive layer lead pad.

Detailed Description

The technical solution of the present invention is described in detail below with reference to the accompanying drawings 1-7 and the embodiments, wherein: 1. a transparent substrate; 2. a first UV glue layer; 3. a first conductive layer; 4. a second UV glue layer (reinforcing insulating support layer); 5. a third UV adhesive layer; 6. a second conductive layer; protective layers (not shown in the figures, which may enhance its wear resistance, prevent oxidation or vulcanization of the metal, etc.); 7. an electrical connection region of the first lead region; 8. an electrical connection region of the second lead region.

The terms first UV glue layer, second UV glue layer, third UV glue layer, etc. are used to distinguish the layer structures, and do not mean that the layer structures only contain UV glue, for example, the first and third UV glue layers include the conductive structures according to the structural description and the drawings thereof.

As shown in fig. 1, the present embodiment discloses an ultrathin composite transparent conductive film, which includes a transparent substrate 1, a first UV glue layer 2 is disposed on the transparent substrate 1, and a first conductive layer 3 is made of a conductive material that is patterned and imprinted in a plurality of grid grooves on the first UV glue layer 2; a third UV glue layer 5 is disposed on the transparent reinforced insulating support layer 4, and the second conductive layer 6 is made of a conductive material that is patterned and imprinted in a plurality of grid grooves on the third UV glue layer 5.

It should be noted that, the third UV glue film that includes the second conducting layer sets up on the second UV glue film (strengthening the insulating supporting layer) of solidification after the impression, can increase substantially the insulating dynamics between first conducting layer and the second conducting layer, avoid the conducting layer to run through this problem, as shown in fig. 3, impression third UV glue film on the transparent strengthening insulating supporting layer after the solidification, after filling conducting material preparation second conducting layer behind the solidification third UV glue film, the problem of short circuit between the layer hardly appears, thereby improve the yield of product greatly.

The transparent substrate is a polymer layer commonly used for conductive films. The materials of the first UV glue layer, the third UV glue layer and the second UV glue layer (the reinforced insulation support layer) may be UV curing glue or thermosetting paint, and preferably UV curing glue. The surfaces of the first UV adhesive layer and the third UV adhesive layer are smooth as much as possible after curing, for example, the friction coefficient is 0.1-0.4, and conductive materials can be conveniently filled in the first UV adhesive layer and the third UV adhesive layer in a blade coating mode. The surface of the second UV adhesive layer, namely the cured adhesive layer of the reinforced insulation supporting layer, has certain roughness, and the optimal friction coefficient is 0.4-1.0, so that the reinforced insulation supporting layer has enough adhesive force, and the adhesive degree of the first UV adhesive layer and the third UV adhesive layer is increased.

The adhesion promotion treatment may be performed between the layers, e.g., the transparent substrate, the first UV glue layer, the second UV glue layer and the third UV glue layer, or the adhesion promotion coating may be applied according to conventional techniques. This conventional treatment of the adhesion promoter layer does not itself serve to reinforce the insulation and support. If the same UV curing adhesive is used for the first UV adhesive layer, the third UV adhesive layer and the second UV adhesive layer (reinforcing insulation support layer), a tackifying treatment can be adopted or an adhesion promoting layer can be arranged for better combination. The main materials of the adhesion promotion layer used conventionally can be polyacetylene, polyaniline, polythiophene, graphene, polyethylene terephthalate, polyurethane and the like, the adhesion promotion layer is usually coated on the surface of the substrate in a coating mode to achieve the effect of bonding with an upper layer structure, and the coating thickness range is 10-100 nm.

Except that the transparent substrate material selects materials such as PET, PI polyimide and the like according to different application scenes and requirements, in order to strengthen insulation between conducting layers, the optimal thickness of the reinforced insulation supporting layer is 5-10 micrometers, and the reinforced insulation supporting layer is solidified and formed after imprinting, so that the surface is smooth, and the situation of different thicknesses can not occur.

The yield of the product can reach more than 90% due to the effect of enhancing the insulation and support of the insulation support layer, which is specifically described in fig. 2, fig. 3, fig. 5, fig. 6 and the following tables.

The environmental tests were performed as follows, test conditions: the temperature is 85 ℃, the humidity is 85% RH, the time is 240 hours, and the electrification test is carried out. The test method comprises the following main steps: 1. extracting a test sample; 2. before testing, the appearance is checked, and whether the function is qualified is determined; 3. and (3) putting into a test box, wherein the test conditions are as follows: electrifying at 85 ℃ and 85% RH humidity for 240 hours; 4. taking out the product after the test condition is reached; 5. after the product is static for 24 hours, the appearance is checked, and a function test is carried out; 6. at the end of the test, the data are recorded as in the following table.

The factors influencing the production yield of the product are mainly the product structure, the product without the reinforced insulation supporting layer has the phenomenon of short circuit of an upper lead and a lower lead, and the reinforced insulation supporting layer (the patent scheme) does not have the bad phenomenon.

As for the structure without the reinforced insulating support layer, that is, the structure in which the double-layer patterned transparent conductive film is directly disposed on the transparent substrate, as shown in fig. 2, which is a research and development reference example of the inventor, in the conductive film of this structure, the transparent polymer layer may contain a large number of minute defects due to high-temperature processing cracking, solvent volatilization, defects formed in the polymer, and the like, and the conductive material of the upper conductive layer easily penetrates from the defects to the lower conductive layer, so that a short circuit between the two conductive layers is relatively easily generated. The short circuit problem causes the product to be unstable, the reject ratio is very high, the real industrialized mass production cannot be realized, and the short circuit problem is particularly serious when a large-size conductive film is manufactured.

Although the inventors tried to increase the thickness of the upper transparent adhesive layer as much as possible and prevent the short circuit between the upper conductive layer and the lower conductive layer, the inventors found that the effect of improving the product stability and yield is very limited, as shown in fig. 6, and the effect of bending resistance is also not good.

Referring to fig. 3 and 5, the thickness of the third UV glue layer is 8 micrometers, and the depth of the grid-shaped grooves embossed on the third UV glue layer is 5 micrometers. As can be seen from the figure, when the thickness of the reinforced insulating support layer, i.e., the second UV glue layer, is 5 micrometers or more, the yield thereof is close to 100%. The yield here refers to a yield of testing the interlayer short circuit between the first conductive layer and the second conductive layer after the reinforced insulating support layer is added, and the higher the yield, the lower the probability of interlayer short circuit.

Furthermore, the material of the second UV adhesive layer can be different from that of the third UV adhesive layer as the reinforced insulating support layer, the UV adhesive layers made of different materials are easy to attach, or the difference between the refractive indexes of the material of the reinforced insulating support layer and the refractive index of the material of the third UV adhesive layer is less than 0.3, so that the light transmittance of the product can not be reduced or hardly reduced due to the two materials with the same or similar refractive indexes. The grid grooves of the first UV adhesive layer and the third UV adhesive layer are formed by adopting a patterned imprinting technology, the conductive material is a metal conductive material or a non-metal conductive material, and preferably, the conductive material is silver, copper or graphene and the like.

Preferably, the thickness of the first UV adhesive layer is 8-12 microns, and the thickness of the first conductive layer is 4-5 microns; the thickness of the third UV adhesive layer is 8-12 micrometers, and the thickness of the second conductive layer is 4-5 micrometers; the thickness of the reinforcing insulating support layer is 5-10 microns.

In order to realize the function of multi-point touch, the two transparent adhesive layers are provided with a conductive layer and lead wire areas for communicating the conductive layer with an external data processing device, the lead wire areas are distributed on at least one side of the periphery of the conductive layer, and the lead wire areas are electric connection areas of the lead wire areas, which are areas formed by gathering a plurality of lead wires connected with the conductive layer, as shown in fig. 7.

The first UV adhesive layer is provided with a first conductive layer and a first lead wire area, and the first lead wire area is an area formed by gathering a plurality of lead wires connected with the first conductive layer; and a second conducting layer and a second lead wire area are arranged on the third UV adhesive layer, and the second lead wire area is an area formed by gathering a plurality of lead wires connected with the second conducting layer. The first UV adhesive layer is subjected to patterned imprinting and curing to form a grid-shaped groove of the first conducting layer, a lead groove of the first lead area and an alignment pattern groove of the first alignment mark, and the grid-shaped groove of the first conducting layer, the lead groove of the first lead area and the alignment pattern groove of the first alignment mark are filled with conducting materials; the surface of the third UV adhesive layer is subjected to patterned imprinting and curing to form a latticed groove of the second conducting layer, a lead groove of the second lead area and an alignment pattern groove of the second alignment mark, wherein the latticed groove of the second conducting layer, the lead groove of the second lead area and the alignment pattern groove of the second alignment mark are filled with conductive materials; the patterns of the first alignment mark and the second alignment mark are either reserved or cut in the transparent conductive film product. The electric connection region of the first lead region is not coated with a second layer of UV curing adhesive, and the electric connection region of the second lead region of the third UV adhesive layer is not overlapped with the electric connection region of the first lead region of the first UV adhesive layer.

Furthermore, according to different application requirements, a reinforced insulating support layer may be further disposed on the upper surface of the third UV glue layer, and then a polymer layer is disposed on the reinforced insulating support layer, the polymer layer is patterned and imprinted to form a grid-shaped groove, the grid-shaped groove is filled with a conductive material to form a third conductive layer, and the third conductive layer may be connected to a chassis or grounded, so as to serve as an electromagnetic shielding layer.

Furthermore, the third conducting layer can be connected with an external device and then connected with current, so that the third conducting layer becomes a heating layer, the whole touch product can resist low temperature, and the third conducting layer can be kept stable in a low-temperature working environment.

Furthermore, an insulation reinforcing and insulation supporting layer can be added on the surface of the third conducting layer serving as the electromagnetic shielding layer, then a polymer layer is arranged on the reinforcing and insulation supporting layer, grid-shaped grooves are formed through graphical imprinting, conducting materials are filled in the grid-shaped grooves to form a fourth conducting layer, and the fourth conducting layer can be connected with an external device to be connected with current, so that the fourth conducting layer becomes a heating layer. Therefore, the whole conductive film product is provided with four conductive layers, according to different application scenes, particularly in an environment emphasizing safety or an environment emphasizing low-temperature work, two conductive layers can be used for touch display, one conductive layer is used as an electromagnetic shielding layer, the other conductive layer is used as a heating layer, the product can be used in a low-temperature environment without influencing touch, and meanwhile, the electromagnetic shielding is safer, and is not shown in the figure.

The embodiment also provides a preparation method of the ultrathin composite transparent conductive film, which comprises the following main steps:

1. firstly, coating UV curing glue on the surface of a transparent substrate.

The transparent substrate may preferably be aged before the UV-curable adhesive is applied to the surface of the transparent substrate. Of course, the transparent substrate may not be aged depending on the material, but a part of the material may be aged to cause dimensional deviation of the upper and lower lines. Wherein, the aging mode can be that the transparent substrate is placed under a plasma blower with the temperature of 50-150 ℃ for 5-60 s to remove impurities on the surface of the substrate and stabilize the property of the substrate; the transparent substrate can be made of PET, PC, PMMA and the like, and the thickness of the transparent substrate is 50-200 microns. The UV curing glue can be replaced by thermosetting paint, but the UV glue is preferred.

2. And then carrying out patterned imprinting on the UV curing adhesive based on a patterned imprinting technology and curing to form a first UV adhesive layer with grid-shaped grooves of the first conductive layer and lead grooves of the first lead area.

The patterned imprinting may be performed by: the method comprises the steps of coating a first UV adhesive layer on a transparent substrate, enabling a metal male die with a patterned pattern to be in rolling or flat pressing contact with the transparent substrate, and simultaneously or in a delayed mode, adopting ultraviolet curing and other means to transfer the pattern on the surface of the male die to the first UV adhesive layer of the transparent substrate so as to form the patterned pattern with the mesh line as the groove. The side line of the graphical pattern is a groove, the width of the groove is 1-20 micrometers, and the depth of the groove is 4-5 micrometers. The thickness of the first UV adhesive layer is 8-12 microns.

3. And filling a conductive material in the groove of the first UV adhesive layer to form a first conductive layer and a first lead area.

In the step, a blade coating technology can be used for filling nano silver paste into a patterned groove formed on the surface of the UV curing adhesive in a stamping mode; according to the self-leveling effect, the nano silver paste can be automatically deposited in the groove in the silver paste scraping and coating process. In order to enable silver paste to be uniformly distributed in the patterned groove, the silver paste can be coated in a blade coating mode for multiple times, and the silver particles are ensured to be filled in the groove. And after the blade coating is finished, polishing the surface of the UV curing adhesive to remove redundant silver paste. The first lead section is disposed at a periphery of the first conductive layer.

4. And coating UV curing glue on the surface of the first UV glue layer to form a second UV glue layer serving as a reinforced insulating support layer. The second UV glue layer can be embossed or coated using a flat non-patterned mould or a high surface finish mirror roller, which ensures the surface finish of the reinforcing insulating support layer. The thickness of the reinforcing insulating support layer is preferably 5-10 micrometers. Since the lead pads need to communicate with an external device, the electrical connection regions of the first lead pads cannot be coated with a UV adhesive layer in order to prevent the subsequent process from damaging the structure or conductivity of the lead pads. The second UV glue layer can also be arranged by other methods such as selective coating.

5. And further coating UV curing glue on the second UV glue layer to form a third UV glue layer, and carrying out alignment patterning stamping and curing on the UV curing glue to form the third UV glue layer with the latticed grooves of the second conducting layer and the lead grooves of the second lead area.

In order to ensure that the positions of the latticed groove areas of the second conducting layer and the latticed groove areas of the first conducting layer are not greatly deviated, the molds for imprinting the first UV adhesive layer and the third UV adhesive layer are provided with a plurality of positioning targets which are respectively distributed around the molds and do not coincide with other patterns. And when the third UV adhesive layer is imprinted, carrying out alignment treatment on the positioning target on the mold and the positioning target imprinted on the first UV adhesive layer. The first UV adhesive layer is imprinted with a contraposition pattern groove with a first contraposition mark; the third UV adhesive layer is imprinted with a contraposition pattern groove with a second contraposition mark; the patterns of the first alignment mark and the second alignment mark are either reserved or cut in the transparent conductive film product.

The second lead area is arranged on the periphery of the second conductive layer, and the electric connection area of the second lead area cannot be overlapped with the electric connection area of the first lead area.

6. And filling a conductive material in the groove of the third UV adhesive layer to form a second conductive layer and a second lead area.

And the first lead area and the second lead area are connected with a test device to test the function and performance of the ultrathin composite transparent conductive film.

The steps are the preparation method of the single ultrathin composite transparent conductive film.

Since the steps for manufacturing the ultrathin composite transparent conductive film are many, and if the ultrathin composite transparent conductive film is manufactured in a single piece, the efficiency is extremely low, the embodiment improves on the basis of the preparation method, and provides a preparation method for producing the ultrathin composite transparent conductive film in a large scale, which comprises the following main steps:

1. firstly, coating a first layer of UV curing adhesive on the surface of a roll of aged transparent substrate through a roll-to-roll process, and then carrying out graphical imprinting and curing on the UV curing adhesive to form a whole roll of film material comprising a plurality of first UV adhesive layers which are connected end to end, namely the film material forming a plurality of continuous first UV adhesive layer units, wherein the first UV adhesive layer is provided with latticed grooves of a first conductive layer, lead grooves of a first lead area and grooves of a positioning target.

2. And filling conductive materials in the latticed grooves of the first conductive layers of the plurality of first UV adhesive layers and the lead grooves of the first lead areas on the whole roll of the film material by adopting a plurality of scrapers in a roll-to-roll scraping manner to form a plurality of first conductive layers and first lead areas.

The specific roll-to-roll knife coating method comprises the following steps: the whole roll of film material moves under the traction of the automatic traction device, the sprayer automatically sprays the conductive material, a plurality of scrapers are perpendicular to the moving direction, the scrapers are arranged above the film material and are in contact with the film material, the scrapers are kept still, the film material moves, the conductive material is not wasted and manpower is saved, and meanwhile, the automatic wiping head can be arranged to wipe redundant conductive material on the surface of the first UV adhesive layer.

3. And coating a second layer of UV curing adhesive on the surface of the first UV adhesive layer through a roll-to-roll process, and carrying out pattern-free imprinting and curing on the second layer of UV curing adhesive, so that a plurality of reinforced insulating support layers, namely a second UV adhesive layer, are formed on the surfaces of a plurality of first UV adhesive layers of the whole roll of film material, wherein the surfaces of the electric connection regions of the first lead regions of the first UV adhesive layers are not coated with the UV adhesive layers.

4. After the positioning target on the die for impressing the third UV adhesive layer is aligned with the positioning target impressed on the first UV adhesive layer, coating a third layer of UV curing adhesive on a second UV adhesive layer (reinforced insulation supporting layer) of the whole roll of film material through a roll-to-roll process, and carrying out graphical impressing and curing on the UV curing adhesive to form a whole roll of film material comprising a plurality of end-to-end connected third UV adhesive layers, wherein the third UV adhesive layer is provided with latticed grooves of a second conducting layer and lead grooves of a second lead area.

Due to the alignment treatment, the latticed groove areas of the plurality of second conducting layers of the whole roll of the film material are respectively arranged right above the latticed groove areas of the plurality of first conducting layers, and the electric connection areas of all the second lead areas are staggered with the electric connection areas of the first lead areas.

5. And filling a conductive material in the grooves of the plurality of third UV adhesive layers of the whole roll of film material by adopting a plurality of scrapers in a roll-to-roll scraping manner to form a plurality of second conductive layers and a second lead area.

6. And slicing the whole roll of ultrathin composite transparent conductive film to obtain a plurality of ultrathin composite transparent conductive films.

The preparation method can be used for producing ultrathin composite transparent conductive films in large batch, is high in production efficiency, and can reduce the waste of the conductive materials by adopting a roll-to-roll blade coating mode of the conductive materials, reduce the production cost by taking the nano silver paste as an example, and ensure that 500 ml of nano silver paste in one bottle needs ten thousands of yuan.

Example two

As shown in fig. 4, the present embodiment discloses an ultrathin composite transparent conductive film, which includes a transparent substrate 1, a first conductive layer 3 disposed on the transparent substrate, and a second conductive layer 6 disposed on the first conductive layer 3, wherein a transparent reinforced insulating support layer 4 is disposed between the first conductive layer 3 and the second conductive layer 6, and the second conductive layer 6 is disposed on the cured reinforced insulating support layer 4;

different from the first embodiment, the first conductive layer of the second embodiment is formed by a conductive material filled in the grid groove formed on the transparent substrate 1.

It should be noted that, in the second embodiment, compared with the first embodiment, the first UV glue layer is removed, which is equivalent to that the thickness of the ultrathin composite transparent conductive film is thinner, but the effect of directly imprinting the grid grooves on the transparent substrate is not good when the grid grooves are not imprinted on the UV light curing coating, because the UV light curing coating is still in a liquid state during imprinting, and the groove depth is not rebounded after the imprinting is completed and curing is performed.

The second embodiment also provides a preparation method of the ultrathin composite transparent conductive film, which comprises the following main steps:

(1) graphically imprinting the latticed grooves on the transparent substrate 1;

(2) filling a conductive material in the groove embossed in the step (1) to form a first conductive layer 3;

(3) coating a second UV glue layer, namely a transparent reinforced insulating support layer 4, on the first conductive layer 3 and curing;

(4) coating a third UV adhesive layer 5 on the transparent reinforced insulating support layer 4, and graphically stamping latticed grooves on the third UV adhesive layer 5 and curing;

(5) and (4) filling the grooves stamped in the step (4) with a conductive material to form a second conductive layer 6.

In the step (1), a mold can be used for directly imprinting and forming the latticed grooves on the transparent substrate (which can be PET or PMMA), the depth of the grooves is 4-5 micrometers, and the specific implementation modes and parameters of the other steps are shown in the preparation method of the first embodiment.

It should be noted that the dimensional parameters in the above embodiments are only for illustrating the implementation state of the present invention, and the width of the groove is taken as an example, as long as the width of the groove is smaller than the limit resolution of human eyes, i.e. the normal viewing as the display device is not affected. The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. An ultra-thin composite transparent conductive film, includes transparent substrate, its characterized in that:

2. The ultra-thin composite transparent conductive film of claim 1, wherein: the first UV adhesive layer is subjected to patterned imprinting and curing to form a grid-shaped groove of the first conducting layer, a lead groove of the first lead area and an alignment pattern groove of the first alignment mark, the grid-shaped groove of the first conducting layer, the lead groove of the first lead area and the alignment pattern groove of the first alignment mark are filled with a conducting material, and the grid-shaped groove of the first conducting layer, the lead groove of the first lead area and the alignment pattern groove of the first alignment mark are all deeper than the first UV adhesive layer;

3. The ultra-thin composite transparent conductive film of claim 1, wherein: the thickness of the second UV adhesive layer is 1-10 microns.

4. The ultra-thin composite transparent conductive film of claim 1, wherein: the second UV adhesive layer and the third UV adhesive layer are made of different materials, and the first UV adhesive layer and the third UV adhesive layer are made of the same or different materials.

5. The ultra-thin composite transparent conductive film of claim 1, wherein: the electric connection region of the first lead region is not coated with a second layer of UV curing adhesive, and the electric connection region of the second lead region of the third UV adhesive layer is not overlapped with the electric connection region of the first lead region of the first UV adhesive layer.

6. The ultra-thin composite transparent conductive film of claim 1, wherein:

an adhesion promoting layer is coated between the transparent substrate and the first UV adhesive layer or adhesion promoting treatment is carried out;

7. The ultra-thin composite transparent conductive film of claim 1, wherein: the second UV adhesive layer is a composite layer formed by coating UV curing adhesive on the surface of the first UV adhesive layer for multiple times, and the surface of the electric connection area of the first lead area is not covered with the second UV adhesive layer.

8. The ultra-thin composite transparent conductive film of claim 1, wherein: the latticed grooves of the first conducting layer and the second conducting layer and the lead grooves of the first lead area and the second lead area are filled with nano silver paste, nano copper paste, graphene materials, nano silver wires or carbon nanotube materials.

9. The ultra-thin composite transparent conductive film of claim 1, wherein: the upper surface of third UV glue film is provided with the protective layer, the protective layer is polymer layer, and first UV glue film, second UV glue film, third UV glue film, protective layer and transparent basement form compound transparent conducting film together, the electric connection district of the second lead wire district on third UV glue film does not coincide with the electric connection district of the first lead wire district on first UV glue film.

10. A preparation method of an ultrathin composite transparent conductive film is characterized by comprising the following steps:

11. The structure of the ultrathin composite transparent conductive film comprises a transparent substrate, and is characterized in that: a first UV adhesive layer, a second UV adhesive layer and a third UV adhesive layer are arranged on one surface of the transparent substrate;

12. A touch display panel comprises a display device, and is characterized in that: the ultrathin composite transparent conductive film of any one of claims 1-9 is further included.

13. A large-size touch control integrated machine device comprises a display device, a CPU (central processing unit) processor and a power supply, and is characterized in that: the display device comprises a touch panel comprising the ultrathin composite transparent conductive film of any one of claims 1-9.

14. A composite transparent conductive film comprising a transparent substrate, characterized in that:

one surface of the transparent substrate is subjected to patterned imprinting and forms a grid-shaped groove of the first conducting layer and a lead groove of the first lead area, and the grid-shaped groove of the first conducting layer and the lead groove of the first lead area are filled with conducting materials;